Serum Prokineticin 2 Levels Correlate with Diabetic Kidney Disease in Patients with Type 2 Diabetes

Serum Prokineticin 2 Levels Correlate with Diabetic Kidney Disease in Patients with Type 2 Diabetes | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Serum Prokineticin 2 Levels Correlate with Diabetic Kidney Disease in Patients with Type 2 Diabetes Ziqi Meng, Jun Qin, Yujing Sun, Nan Zang, Hulian Huang, Xinxu Wang, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9150077/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 13 You are reading this latest preprint version Abstract Introduction: Prokineticin 2 (PROK2) is a secreted protein, that plays a critical role in the circadian regulation of energy homeostasis. However, its association with type 2 diabetes mellitus (T2DM) and diabetes-related complication remains poorly understand. This study aimed to investigate the relationship between serum PROK2 levels, T2DM and diabetic kidney disease (DKD). Methods A total of 255 participants were enrolled, including 40 healthy controls and 215 patients with T2DM. DKD was defined as a urinary albumin-to-creatinine ratio (UACR) ≥ 0.03 g/g, or an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m². Serum PROK2 concentrations were quantified using enzyme-linked immunosorbent assay. Binary logistic regression models were applied to evaluate the associations between PROK2 levels and the risks of T2DM and DKD. Correlation analyses were performed to assess the relationships between PROK2 and renal function indicators, including UACR and eGFR. Results Serum PROK2 levels differed significantly among the study groups ( P < 0.05), with the lowest concentrations observed in patients with DKD. After adjustment for potential confounders, higher serum PROK2 levels were independently associated with a lower risk of T2DM (odds ratio [OR] = 0.492, P = 0.001) and DKD (OR = 0.679, P = 0.046). Furthermore, PROK2 levels were negatively correlated with UACR ( r =–0.212, P = 0.0007) and positively correlated with eGFR ( r = 0.271, P < 0.0001). Conclusion Serum PROK2 levels are significantly reduced in patients with T2DM, particularly among those with DKD. These findings suggest that PROK2 may serve as a novel circulating biomarker for assessing renal impairment in individuals with T2DM. Prokineticin 2 Diabetic Kidney Disease Urinary Albumin-to-Creatinine Ratio Estimated Glomerular Filtration Rate Figures Figure 1 Figure 2 Figure 3 INTRODUCTION According to the international diabetes federation (IDF) Diabetes Atlas (11th edition), as of 2024, the global prevalence of diabetes mellitus (DM) among individuals aged 20–79 years has reached 11.1%, corresponding to more than 589 million affected individuals worldwide. 1 Data from the global burden of disease (GBD) Study, further indicate that Type 2 diabetes (T2DM) is the predominant form of diseases, accounting for over 90% cases globally. 2 T2DM currently ranks as the eighth leading cause of global disease burden and is projected to become the second leading cause by 2050. 3 Diabetic kidney disease (DKD) is among the most prevalent microvascular complications of DM and represents a major subtype of chronic kidney disease (CKD). Clinically, DKD is characterized by a progressive increase in urinary protein excretion accompanied by a gradual decline in renal function, ultimately leading to end-stage renal disease. This condition places a substantial burden on healthcare systems, worldwide and markedly reduces life expectancy and quality of life. 4 5 The pathogenesis of DKD arises from the synergistic interplay of multiple factors and signaling pathways, and substantial progress has been made in elucidating these mechanisms in recent years. DKD development is driven by a complex network of pathological processes initiated by chronic hyperglycemia. This persistent metabolic disturbance promotes the formation of advanced glycation end products (AGEs) and excessive oxidative stress, which in tern activate key intracellular signaling pathways, including protein kinase C (PKC), mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase/Akt (PI3K/Akt), and nuclear factor-κB (NF-κB), thereby including inflammation and cellular injury. 6 7 Simultaneously, activation of the intrarenal renin-angiotensin-aldosterone system (RAAS) further exacerbates glomerular hemodynamic stress and enhances profibrotic signaling. 6 These processes collectively maintain a chronic inflammatory microenvrionment mediated by cytokines and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, leading to capillary rarefaction and progressive tissue damage. 7 8 Ultimately, sustained inflammation and cellular dysfunction converge to drive renal fibrosis, predominantly through activation of the transforming growth factor-β (TGF-β)/Smad pathway. Emerging evidence further implicates specific macrophage subsets and mediators such as galectin-3 in amplifying fibrotic progression. 9 10 Despite these advances, the precise molecular mechanisms underlying DKD remain incompletely understood due to the disease’s complex and multifactorial nature. Accordingly, continued investigation into the biological underpinnings of DKD is essential for the development of effective therapeutic strategies and the advancement of clinical research. In recent years, secreted proteins with pleiotropic biological functions have attracted increasing attention for their roles in metabolic disorders and kidney injury, with human prokineticin2 (PROK2), emerging as a molecule of particular interest. PROK2 is a key member of the prokineticin family 11 and was initially identified in the gastrointestinal tract. 12 Recent clinical studies have demonstrated an association between circulating PROK2 levels and metabolic syndrome (MetS). 13 PROK2 functions as an endogenous ligand for two G protein-coupled receptors, prokineticin receptor 1 (PKR1) and prokineticin receptor 2 (PKR2), with a higher binding affinity for PKR1. 14 Activation of PKR1 predominantly triggers cardioprotective and metabolic signaling pathways, including the PI3K/protein kinase B (PI3K/Akt) pathway, which is essential for cell survival and insulin sensitivity. 15 Marie Mortreux and colleagues reported that plasma PROK2 levels were significantly lower in individuals with T2DM compared with normoglycemic subjects; however, this difference was no longer statistically significant after adjustment for body mass index (BMI) and energy intake. In contrast, genetic variants in PROK2 have been linked to incident hyperglycemia (T2DM and impaired fasting glucose), MetS, and obesity. 16 In addition, PKR1 has been shown to play a critical role in kidney development and the maintenance of normal renal function 17 18 and experimental evidence suggests that the PROK2/PKR1 signaling pathway may exert protective effects against DKD in murine models. 19 The existing evidence suggests that PROK2 may play an important role in the pathogenesis of diabetes and DKD. However, direct evidence from human studies examining the associations between PROK2 and T2DM or DKD remains extremely limited. To date, no studies have clearly characterized the serum expression profile of PROK2 in patients, with DKD, nor have they systematically evaluated its relationships with key clinical indicators of renal injury, such as the urinary albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR). In light of these research gaps, the present study aims to comprehensively investigate the associations between serum PROK2 levels and T2DM as well as DKD, thereby providing novel insights into the biological mechanisms underlying DKD pathogenesis. METHOD Participants A total of 255 participants were enrolled in this study, including 40 healthy controls and 215 patients with T2DM, all of whom were recruited from Qilu Hospital of Shandong University between May 2024 and November 2025. Eligible participants were aged 35–80 years and had no severe physical disabilities or psychiatric disorders. Individuals were excluded if they met any of the following criteria: (1) diagnosis of type 1 diabetes or other specific types of diabetes; (2) presence of hepatic or renal diseases unrelated to diabetes; (3) acute or active conditions, including urinary tract infections, diabetic ketoacidosis, or diabetic foot; or (4) a history of malignant tumors. The diagnosis of diabetes was established according to the 2006 world health organization (WHO) criteria. 20 Data Collection Demographic characteristics, clinical parameters, and medical history were systematically obtained for all participants through the electronic medical record system of Qilu Hospital of Shandong University. Collected variables included age, sex, duration of T2DM, BMI, blood pressure (BP), history of hypertension, smoking status, alcohol consumption, glycated hemoglobin (HbA1c), fasting C-peptide, fasting blood glucose (FBG), serum albumin, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglycerides (TG), serum creatinine (Scr), and UACR. The eGFR was calculated using the CKD epidemiology collaboration equation. 21 All laboratory assays were conducted by the Department of Laboratory Medicine at Qilu Hospital ensuring standardized procedures and data reliability. Serum PROK2 concentrations were measured quantitatively using a commercially available enzyme-linked immunosorbent assay kit (EH3582; FineTest, Wuhan, Hubei Province, China). Definitions and Grouping Criteria DKD was defined as a UACR ≥ 0.03 g/g or an eGFR < 60 mL/min/1.73 m², in accordance with the American diabetes association standards of medical care in diabetes 22 and the national kidney foundation kidney disease outcomes quality initiative guidelines. 23 Based on these criteria participants were classified into three groups: (1) healthy controls, defined as individuals without diabetes or albuminuria; (2) patients with T2DM without DKD; and (3) patients with T2DM and DKD. Statistical Analysis The Kolmogorov-Smirnov test was applied to assess the normality of continuous variables and homogeneity of variance was evalutaed using the F-test. Continuous variables are expressed as the mean±standard deviation for normally distributed data or as the median (interquartile range) for non-normally distributed data, whlie categorical variables are presented as counts (percentages). Between group differences were analyzed using one-way analysis of variance followed by the least significant difference post hoc test for normally distributed continuous variables, the Kruskal-Wallis test for non-normally distributed continuous variables, and the Pearson chi-square(χ2)test for categorical variables. Binary logistic regression models were constructed to evaluate the association between serum PROK2 levels and the risks of T2DM and DKD. Correlation analyses were performed to examine the relationships between serum PROK2 levels and renal function indices, including UACR and eGFR. A two-sided p value < 0.05 was considered statistically significant. All statiscal analyses were conducted using SPSS software (version 25.0; IBM Corp., Armonk, NY, USA), and graphical representations were generated using GraphPad Prism (version 10.1; GraphPad Software, San Diego, CA, USA). RESULTS Clinical characteristics and serum PROK2 levels of participants in different groups Compared with patients with T2DM without DKD, those in the DKD group exhibited significantly higher BP, UACR, HbA1c, FBG, and a greater proportion of angiotensin-converting enzyme inhibitor (ACEI)/angiotensin II receptor blocker (ARB) and insulin use. In contrast, eGFR serum albumin levels, and the proportion of metformin use were significantly lower in the DKD group (Table 1 ). In addition, serum PROK2 concentrations were reduced in patients with T2DM compared with healthy controls and were lowest in patients with DKD (Fig. 1 ). Table 1 Demographic and biochemical parameters of the study population in different groups. n Healthy controls T2DM without DKD T2DM with DKD 40 115 100 Age(years) 59.58 ± 3.86 57.91 ± 8.37 58.66 ± 9.67 Male, n(%) 21(52.5) 65(56.5) 62(62) BMI(kg/m2) 24.32 ± 3.03 25.11 ± 4.03 25.06 ± 4.05 Drinking, n (%) N/C 32(27.8) 29(29) Smoking, n (%) N/C 28(24.3) 24(24) Hypertension, n (%) 6(15) 56(48.7)* 71(71)*† Diabetes duration (years) 0 10(6, 18) 16(8.25, 20) SBP (mm Hg) 123.78 ± 11.48 131.86 ± 17.26* 139.91 ± 20.90*† DBP (mm Hg) 76.45 ± 8.46 77.59 ± 10.35 81.01 ± 11.93*† TC (mmol/L) 5.07 ± 0.85 4.19 ± 1.15* 4.46 ± 1.37* LDL-C (mmol/L) 2.99 ± 0.69 2.46 ± 0.90* 2.53 ± 1.01* HDL-C (mmol/L) 1.46 ± 0.30 1.21 ± 0.32* 1.20 ± 0.37* TG (mmol/L) 1.17(0.95, 1.55) 1.20(0.89, 1.98) 1.29(0.95, 2.18) Serum albumin (g/L) 46.24 ± 1.68 42.41 ± 3.16* 41.21 ± 4.74*† eGFR (mL/min/1.73m 2 ) 93.72 ± 11.16 99.88 ± 11.22 83.15 ± 26.45*† UACR(g(Alb)/g(Cr)) 0.00(0.00, 0.00) 0.01(0.01, 0.01) 0.09(0.04, 0.30) *† HbA1c (%) 5.66 ± 0.25 8.22 ± 1.69* 8.9 ± 2.04*† FBG (mmol/L) 4.62 ± 0.51 6.91 ± 2.00* 7.70 ± 3.26*† Fasting C-peptide (ng/mL) N/C 1.36 ± 0.65 1.65 ± 1.10 ACEI or ARB treatment, n (%) N/C 23(20) 33(33)† Metformin treatment, n (%) N/C 106(92.2) 74(74)† SGLT2i treatment, n (%) N/C 42(36.5) 27(27) GLP-1 treatment, n (%) N/C 9(7.8) 6(6) Insulin therapy, n (%) N/C 52(45.2) 67(67)† * P < 0.05 compared with the healthy control group. † P < 0.05 for comparison between T2DM patients with DKD and without DKD groups. BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; TC, total cholesterol; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; TG, triglyceride; eGFR, estimated glomerular filtration rate; UACR, urinary albumin-to-creatinine ratio; HbA1c, glycated hemoglobin; FBG, fasting blood glucose; ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin II receptor blocker; SGLT2i, sodium-glucose cotransporter 2 inhibitor; GLP-1 RA, glucagon-like peptide-1 receptor agonist. Correlation analysis between serum PROK2 levels and T2DM To elucidate the association between serum PROK2 levels and T2DM, binary logistic regression analyses were performed (Table 2 ). The results indicated that serum PROK2 levels were independently associated with the presence of T2DM, even after adjustment for multiple potential confounders, including sex, age, BMI, systolic BP (SBP), TG, LDL-C and eGFR ( P < 0.05). Table 2 Binary logistic regression analysis of the relationship between serum PROK2 levels and T2DM Model 1 OR (95%CI) P value 0.565 (0.403 to 0.792) 0.001 Model 2 0.506 (0.353 to 0.727) 0.000 Model 3 0.492 (0.322 to 0.751) 0.001 Model 1: Unadjusted. Model 2: Adjusted for sex and age. Model 3: Adjusted for sex, age, BMI, systolic blood pressure, triglycerides, low-density lipoprotein cholesterol and eGFR. Correlation analysis between serum PROK2 levels and DKD Binary logistic regression analysis was performed to examine the association between serum PROK2 levels and the presence of DKD (Table 3 ). The findings demonstrated that serum PROK2 levels remains significantly associated with DKD, after adjustment for a comprehensive set of potential confounders, including sex, age, BMI, SBP, serum albumin, HbA1c, fasting C-peptide, TG, LDL-C, smoking status, alcohol consumption history, duration of diabetes, and the use of ACEIs/ARBs and SGLT2 inhibitors. In addition, the relationships between serum PROK2 levels and renal function parameters were further explore across all participants. Spearman correlation analysis revealed a significant inverse association between serum PROK2 levels and UACR ( r = − 0.212, P = 0.0007) (Fig. 2 ). Consistently, Pearson correlation analysis demonstrated a significantly positive correlation between serum PROK2 levels and eGFR ( r = 0.271, P <0.0001) (Fig. 3 ). Table 3 Binary logistic regression analysis of the association between serum PROK2 levels and DKD in patients with T2DM. Model 1 OR (95%CI) P value 0.679 (0.496 to 0.928) 0.015 Model 2 0.654 (0.472 to 0.906) 0.011 Model 3 0.679 (0.465 to 0.992) 0.046 Model 1: Unadjusted. Model 2: Adjusted for sex and age. Model 3: Adjusted for sex, age, BMI, systolic blood pressure, serum albumin, HbA1c, fasting C-peptide, triglyceride, low-density lipoprotein cholesterol, smoking history, history of alcohol consumption, duration of diabetes, use of ACEIs/ARBs and use of SGLT2i. DISCUSSION The present study systematically examined the associations between serum PROK2 levels and the presence of T2DM and DKD. The results demonstrated that serum PROK2 concentrations were significantly reduced in patients with T2DM compared with healthy controls, with the most pronounced decrease observed in patients with DKD. Further multivariate analyses revealed that serum PROK2 levels were independently associated with both T2DM and DKD. To our knowledge, this study is the first to provide clinical evidence linking circulating PROK2 levels to renal injury in patients with T2DM. PROK2, a secreted protein with pleiotropic biological functions, has been increasingly recognized as an important component of metabolic regulatory networks. 24–26 Clinical studies have demonstrated that PROK2 is closely associated with the development and progression of DM and MetS. 16 Population-based cohort studies have shown that plasma PROK2 concentrations are significantly lower in patients with T2DM than in individuals with normoglycemia, a finding consistent with our results. However, this association became non-significant after adjustment for BMI or caloric intake, suggesting that the relationship between PROK2 and DM may be partially mediated by obesity. 16 In contrast, studies in obese children have reported significantly elevated serum PROK2 levels compared with those in normal-weight children, with PROK2 positively correlated with BMI, fasting insulin levels, and the homeostatic model assessment of insulin resistance. These findings indicate that PROK2 expression exhibits age- and metabolic state-dependent heterogeneity. 27 PROK2 plays a multifaceted role in metabolic regulation and the pathogenesis of diabetes through diverse and integrated mechanisms. Evidence from multiple lines of research highlights its central involvement in energy homeostasis, glucose metabolism, appetite regulation, and protection against diabetic organ damage. As a key modulator of systemic energy balance, PROK2 exerts its biological effects by binding to the G protein-coupled receptors PKR1 and PKR2, thereby activating downstream signaling pathways that regulate glucose utilization and metabolic homeostasis. In humans, genetic polymorphisms in the PROK2 gene have been linked to obesity and diabetes, underscoring its physiological importance in metabolic regulation. 16 25 At the peripheral level, the PROK2/PKR1 signaling pathway promotes energy expenditure by upregulating uncoupling protein 1 expression in brown adipose tissue, facilitating adipose tissue browning and thermogenesis. 25 Additionally, this pathway suppresses preadipocyte proliferation and differentiation, thereby limiting adipose tissue expansion and mitigating obesity development. 28 Consistently, peripheral administration of PROK2 has been shown to reduce body weight in diet-induced obese mice, in part through mechanisms resembling adiponectin signaling. 29 Within the central nervous system, PROK2 functions as a potent anorexigenic neuropeptide. Intracerebroventricular administration of PROK2 markedly suppresses food intake in rodents, whereas neutralization of endogenous PROK2 leads to increased appetite. 30 31 Moreover, peripherally administered PROK2 can access brainstem circuits to exert appetite-suppressing and weight-reducing effects. 29 Beyond its role in metabolic regulation, PROK2 signaling has also been implicated in the development and potential treatment of diabetic complications, particularly diabetic cardiomyopathy. In diabetic hearts, expression levels of PROK2 and its receptors are significantly reduced, accompanied by impaired AKT/GSK3β signaling. Both metformin treatment and exogenous PROK2 administration confer protection against high glucose-induced cardiomyocyte injury through activation of the PROK2/PKR1/AKT axis, effects that are abolished by PKR1 or AKT inhibition. 32 These findings are consistent with earlier observations demonstrating that PROK2/PKR1 signaling mitigates the progression of diabetes, obesity, and associated cardiovascular disorders. 28 Collectively, these studies indicate that PROK2 regulates energy metabolism and glucose homeostasis through coordinated actions on adipose tissue remodeling, appetite control, and protection against diabetes-related organ damage. Our findings further extend this framework by providing clinical evidence that reduced circulating PROK2 levels are closely associated with the development of diabetes, supporting the translational relevance of PROK2 signaling in human metabolic disease. DKD, one of the most prevalent microvascular complications of DM, is characterized by a complex and multifactorial pathogenesis arising from the interplay of genetic susceptibility, metabolic dysregulation, and environmental influences. The disease process is initiated by chronic hyperglycemia, which triggers a network of interconnected pathological pathways that progressively drive renal dysfunction and ultimately renal failure. 33 Early metabolic disturbances, including the accumulation of AGEs and activation of PKC, directly impair glomerular and tubular structures. 34 35 These metabolic insults are further exacerbated by hemodynamic alterations and activation of the intrarenal RAAS, leading to glomerular hypertension and enhanced pro-fibrotic signaling. 36 37 Oxidative stress represents a central pathogenic hub in DKD, largely driven by mitochondrial dysfunction and excessive reactive oxygen species production. This oxidative milieu sustains chronic inflammation through the activation of key transcriptional regulators, including NF-κB and TGF-β signaling pathways. 38 39 Collectively, these metabolic, hemodynamic, oxidative, and inflammatory processes converge to induce podocyte injury, excessive extracellular matrix deposition, and progressive tubulointerstitial fibrosis. The resulting structural and functional deterioration manifests clinically as persistent proteinuria and a gradual decline in glomerular filtration rate. 35 40 The precise mechanistic role of PROK2 in the pathogenesis of DKD has not yet been fully elucidated. Nevertheless, accumulating evidence indicates that the PROK2/PKR1 signaling axis plays a critical role in kidney development and the maintenance of renal structural integrity. Conditional disruption of the PKR1 gene in mice results in marked renal abnormalities, including tubular dilation, reduced glomerular capillary density, increased urinary phosphate excretion, and overt proteinuria. 18 In vitro studies further demonstrate that PROK2, through activation of PKR1, promotes the differentiation of epicardin-positive renal progenitor cells into endothelial and smooth muscle cells, suggesting a pivotal role for PROK2/PKR1 signaling in renal angiogenesis and neovascularization. 18 Consistent with these findings, endothelium-specific PKR1 knockout mice (ec-PKR1⁻/⁻) exhibit severe renal structural disorders characterized by compact, fibrotic glomeruli and elevated phosphate excretion, highlighting the importance of endothelial PKR1 signaling in preserving glomerular architecture 41 Additional mechanistic studies have identified PKR1 as a crucial modulator of mesenchymal-epithelial transition (MET), a key process in nephron formation during kidney development, mediated through NFATc3-dependent signaling pathways. 17 Collectively, these findings suggest that the PROK2/PKR1 pathway exerts a protective role in renal development and vascular homeostasis. In the context of DKD, this protective function may be compromised, as reflected by the significantly lower serum PROK2 levels observed in patients with DKD in the present study. Supporting this hypothesis, recent experimental evidence demonstrates that activation of the PROK2/PKR1 signaling pathway mediates the renoprotective effects of geniposide in DKD mouse models, further implicating this axis in kidney protection under diabetic conditions. 19 This study has several limitations that should be acknowledged when interpreting the findings and guiding future research. First, the cross-sectional design captures exposure and outcome variables at a single time point; consequently, the absence of longitudinal follow-up precludes characterization of dynamic changes in serum PROK2 levels during DKD progression and limits the ability to establish causal relationships. Second, although a robust clinical association between serum PROK2 levels and DKD was observed, the underlying molecular mechanisms through which PROK2 may exert renoprotective effects were not directly investigated. While existing evidence suggests that the PROK2/PKR signaling pathway is involved in the regulation of inflammation and fibrosis, 42 43 its activation status and downstream signaling events in the context of diabetic renal injury warrant further mechanistic validation using experimental models. Third, all participants in this study were of Chinese ethnicity, which may restrict the generalizability of the results to other populations and underscores the need for validation in ethnically diverse cohorts. In conclusion, through rigorous clinical analysis, this study provides the first evidence that lower serum PROK2 levels are independently associated with T2DM and DKD, correlating with key markers of renal impairment. This supports the hypothesis that PROK2 may play an important role in the pathogenesis of T2DM and DKD. However, this work primarily establishes a clinical association; the specific molecular mechanisms, signaling pathways, and full clinical translational value of PROK2 in DKD demand in-depth exploration. Future research must employ an integrated strategy combining basic science and clinical studies to define the prognostic utility of PROK2, establish its functional role in relevant models, and evaluate the feasibility of therapeutic targeting, thereby paving the way for novel diagnostic and therapeutic approaches in DKD. Declarations CONTRIBUTORS ZM and JQ are joint first authors. CW obtained funding. ZM, JL, and LC designed the study. LY, NZ, YS, XZ, HH, XW and ZM collected the data. ZM, CW, and XZ analyzed the data. ZM drafted the manuscript. CW and LC contributed to the interpretation of the results and critical revision of the manuscript for important intellectual content and approved the final version of the manuscript. All authors have read and approved the final manuscript. CW and XZ are the study guarantors. DATA AVAILABLILITY Dataset used in this study is available upon reasonable request to the corresponding author via [email protected] . Competing interests no support from any organization for the submitted work; no financial relationships with any organization that might have an interest in the submitted work in the previous three years, no other relationships or activities that could appear to have influenced the submitted work. Patient consent for publication Not applicable. Ethics approval This study involves human participants and was conducted in accordance with the ethical principles of the Chinese Measures for the Ethical Review of Biomedical Research Involving Humans, the WMA Declaration of Helsinki, and the CIOMS International Ethical Guidelines for Biomedical Research Involving Human Subjects. The study was approved by the Ethics Committee of Qilu Hospital of Shandong University (Ethics Approval No. KYLL-202506-112). All participants provided informed consent before taking part in the study. FUNDING This study was supported by grants from the Natural Science Foundation of Shandong Province (ZR2023MH005). ACKNOWLEDGEMENTS We thank all participants involved in this study. Data Availability Dataset used in this study is available upon reasonable request to the corresponding author via [ [email protected] ](mailto: [email protected] ) . References Genitsaridi I, Salpea P, Salim A, et al. 11th edition of the IDF Diabetes Atlas: global, regional, and national diabetes prevalence estimates for 2024 and projections for 2050. Lancet Diabetes Endocrinol 2025 doi: 10.1016/s2213-8587(25)00299-2 [published Online First: 20251215] Global, regional, and national burden of diabetes from 1990 to 2021, with projections of prevalence to 2050: a systematic analysis for the Global Burden of Disease Study 2021. Lancet 2023;402(10397):203–34. doi: 10.1016/s0140-6736(23)01301-6 [published Online First: 20230622] (IHME) IfHMaE. GBD Foresight Visualization: IHME,University of Washington; 2024 [Available from: https://vizhub.healthdata.org/gbd-foresight accessed 2026-01-05. Naaman SC, Bakris GL. Diabetic Nephropathy: Update on Pillars of Therapy Slowing Progression. Diabetes Care 2023;46(9):1574–86. doi: 10.2337/dci23-0030 Kriz W, Löwen J, Gröne HJ. The complex pathology of diabetic nephropathy in humans. Nephrol Dial Transplant 2023;38(10):2109–19. doi: 10.1093/ndt/gfad052 Pasupulati AK, Nagati V, Paturi ASV, et al. Non-enzymatic glycation and diabetic kidney disease. Vitam Horm 2024;125:251–85. doi: 10.1016/bs.vh.2024.01.002 [published Online First: 20240206] Wang N, Zhang C. Oxidative Stress: A Culprit in the Progression of Diabetic Kidney Disease. Antioxidants (Basel) 2024;13(4) doi: 10.3390/antiox13040455 [published Online First: 20240412] Du H, Wang Y, Zhu Y, et al. MiR-29b Alleviates High Glucose-induced Inflammation and Apoptosis in Podocytes by Down-regulating PRKAB2. Endocr Metab Immune Disord Drug Targets 2024;24(8):981–90. doi: 10.2174/0118715303267375231204103200 Chen Y, Jiang Q, Xing X, et al. Macrophage Derived Galectin-3 Promotes Renal Fibrosis and Diabetic Kidney Disease by Enhancing TGFβ1 Signaling. Adv Sci (Weinh) 2025;12(35):e04032. doi: 10.1002/advs.202504032 [published Online First: 20250813] Chetty S, Yarani R, Swaminathan G, et al. Umbilical cord mesenchymal stromal cells-from bench to bedside. Front Cell Dev Biol 2022;10:1006295. doi: 10.3389/fcell.2022.1006295 [published Online First: 20221012] Negri L, Lattanzi R, Giannini E, et al. Bv8, the amphibian homologue of the mammalian prokineticins, modulates ingestive behaviour in rats. Br J Pharmacol 2004;142(1):181–91. doi: 10.1038/sj.bjp.0705686 [published Online First: 20040405] Li M, Bullock CM, Knauer DJ, et al. Identification of two prokineticin cDNAs: recombinant proteins potently contract gastrointestinal smooth muscle. Mol Pharmacol 2001;59(4):692–8. doi: 10.1124/mol.59.4.692 Wang Y, Guo X, Ma H, et al. Prokineticin-2 is associated with metabolic syndrome in a middle-aged and elderly Chinese population. Lipids Health Dis 2016;15:1. doi: 10.1186/s12944-015-0172-5 [published Online First: 20160105] Chen J, Kuei C, Sutton S, et al. Identification and pharmacological characterization of prokineticin 2 beta as a selective ligand for prokineticin receptor 1. Mol Pharmacol 2005;67(6):2070–6. doi: 10.1124/mol.105.011619 [published Online First: 20050316] Boulberdaa M, Urayama K, Nebigil CG. Prokineticin receptor 1 (PKR1) signalling in cardiovascular and kidney functions. Cardiovasc Res 2011;92(2):191–8. doi: 10.1093/cvr/cvr228 [published Online First: 20110819] Mortreux M, Foppen E, Denis RG, et al. New roles for prokineticin 2 in feeding behavior, insulin resistance and type 2 diabetes: Studies in mice and humans. Mol Metab 2019;29:182–96. doi: 10.1016/j.molmet.2019.08.016 [published Online First: 20190828] Arora H, Boulberdaa M, Qureshi R, et al. Prokineticin receptor 1 is required for mesenchymal-epithelial transition in kidney development. Faseb j 2016;30(8):2733–40. doi: 10.1096/fj.201600181R [published Online First: 20160415] Boulberdaa M, Turkeri G, Urayama K, et al. Genetic inactivation of prokineticin receptor-1 leads to heart and kidney disorders. Arterioscler Thromb Vasc Biol 2011;31(4):842–50. doi: 10.1161/atvbaha.110.222323 [published Online First: 20110127] Dai SJ, Zhang QY, Lan Q, et al. [PK2/PKR1 signaling pathway participates in geniposide protection against diabetic nephropathy in mice]. Zhongguo Zhong Yao Za Zhi 2022;47(6):1611–17. doi: 10.19540/j.cnki.cjcmm.20211122.401 World Health Organization. Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia 2006 [Available from: https://iris.who.int/handle/10665/43588. Levey AS, Stevens LA, Schmid CH, et al. A new equation to estimate glomerular filtration rate. Ann Intern Med 2009;150(9):604–12. doi: 10.7326/0003-4819-150-9-200905050-00006 Chronic Kidney Disease and Risk Management: Standards of Care in Diabetes-2026. Diabetes Care 2026;49(Supplement_1):S246–s60. doi: 10.2337/dc26-S011 KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int 2024;105(4s):S117–s314. doi: 10.1016/j.kint.2023.10.018 Vincenzi M, Nebigil CG. Uncovering the role of prokineticin pathway on Epicardial Adipose Tissue (EAT) development and EAT-associated cardiomyopathy. Trends Cardiovasc Med 2025;35(5):328–38. doi: 10.1016/j.tcm.2025.02.006 [published Online First: 20250213] Magnan C, Migrenne-Li S. Pleiotropic effects of prokineticin 2 in the control of energy metabolism. Biochimie 2021;186:73–81. doi: 10.1016/j.biochi.2021.04.009 [published Online First: 20210429] Nebigil CG. Prokineticin Is a New Linker between Obesity and Cardiovascular Diseases. Front Cardiovasc Med 2017;4:20. doi: 10.3389/fcvm.2017.00020 [published Online First: 20170412] Wang H, Jia Y, Yu X, et al. Circulating Prokineticin 2 Levels Are Increased in Children with Obesity and Correlated with Insulin Resistance. Int J Endocrinol 2021;2021:6630102. doi: 10.1155/2021/6630102 [published Online First: 20210404] Szatkowski C, Vallet J, Dormishian M, et al. Prokineticin receptor 1 as a novel suppressor of preadipocyte proliferation and differentiation to control obesity. PLoS One 2013;8(12):e81175. doi: 10.1371/journal.pone.0081175 [published Online First: 20131204] Beale K, Gardiner JV, Bewick GA, et al. Peripheral administration of prokineticin 2 potently reduces food intake and body weight in mice via the brainstem. Br J Pharmacol 2013;168(2):403–10. doi: 10.1111/j.1476-5381.2012.02191.x Yilmaz U, Tanbek K. Intracerebroventricular prokineticin 2 infusion may play a role on the hypothalamus-pituitary-thyroid axis and energy metabolism. Physiol Behav 2024;283:114601. doi: 10.1016/j.physbeh.2024.114601 [published Online First: 20240603] Gardiner JV, Bataveljic A, Patel NA, et al. Prokineticin 2 is a hypothalamic neuropeptide that potently inhibits food intake. Diabetes 2010;59(2):397–406. doi: 10.2337/db09-1198 [published Online First: 20091123] Yang Z, Wang M, Zhang Y, et al. Metformin Ameliorates Diabetic Cardiomyopathy by Activating the PK2/PKR Pathway. Front Physiol 2020;11:425. doi: 10.3389/fphys.2020.00425 [published Online First: 20200519] Zhang X, Zhang J, Ren Y, et al. Unveiling the pathogenesis and therapeutic approaches for diabetic nephropathy: insights from panvascular diseases. Front Endocrinol (Lausanne) 2024;15:1368481. doi: 10.3389/fendo.2024.1368481 [published Online First: 20240222] Hu Q, Chen Y, Deng X, et al. Diabetic nephropathy: Focusing on pathological signals, clinical treatment, and dietary regulation. Biomed Pharmacother 2023;159:114252. doi: 10.1016/j.biopha.2023.114252 [published Online First: 20230113] Wu T, Ding L, Andoh V, et al. The Mechanism of Hyperglycemia-Induced Renal Cell Injury in Diabetic Nephropathy Disease: An Update. Life (Basel) 2023;13(2) doi: 10.3390/life13020539 [published Online First: 20230215] Rüster C, Wolf G. Renin-angiotensin-aldosterone system and progression of renal disease. J Am Soc Nephrol 2006;17(11):2985–91. doi: 10.1681/asn.2006040356 [published Online First: 20061011] Rahimi Z. The Role of Renin Angiotensin Aldosterone System Genes in Diabetic Nephropathy. Can J Diabetes 2016;40(2):178–83. doi: 10.1016/j.jcjd.2015.08.016 [published Online First: 20151124] Yaribeygi H, Atkin SL, Sahebkar A. Interleukin-18 and diabetic nephropathy: A review. J Cell Physiol 2019;234(5):5674–82. doi: 10.1002/jcp.27427 [published Online First: 20181111] Jin Q, Liu T, Qiao Y, et al. Oxidative stress and inflammation in diabetic nephropathy: role of polyphenols. Front Immunol 2023;14:1185317. doi: 10.3389/fimmu.2023.1185317 [published Online First: 20230721] Ihim SA, Abubakar SD, Zian Z, et al. Interleukin-18 cytokine in immunity, inflammation, and autoimmunity: Biological role in induction, regulation, and treatment. Front Immunol 2022;13:919973. doi: 10.3389/fimmu.2022.919973 [published Online First: 20220811] Dormishian M, Turkeri G, Urayama K, et al. Prokineticin receptor-1 is a new regulator of endothelial insulin uptake and capillary formation to control insulin sensitivity and cardiovascular and kidney functions. J Am Heart Assoc 2013;2(5):e000411. doi: 10.1161/jaha.113.000411 [published Online First: 20131023] Zhao Y, Wu J, Wang X, et al. Prokineticins and their G protein-coupled receptors in health and disease. Prog Mol Biol Transl Sci 2019;161:149–79. doi: 10.1016/bs.pmbts.2018.09.006 [published Online First: 20181024] Lattanzi R, Severini C, Maftei D, et al. The Role of Prokineticin 2 in Oxidative Stress and in Neuropathological Processes. Front Pharmacol 2021;12:640441. doi: 10.3389/fphar.2021.640441 [published Online First: 20210301] Additional Declarations No competing interests reported. Supplementary Files Ethics.pdf Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 01 Apr, 2026 Reviewers agreed at journal 01 Apr, 2026 Reviews received at journal 31 Mar, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers agreed at journal 30 Mar, 2026 Reviewers agreed at journal 30 Mar, 2026 Reviewers agreed at journal 30 Mar, 2026 Reviewers agreed at journal 30 Mar, 2026 Reviewers invited by journal 29 Mar, 2026 Editor invited by journal 20 Mar, 2026 Editor assigned by journal 20 Mar, 2026 Submission checks completed at journal 20 Mar, 2026 First submitted to journal 17 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9150077","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":616215250,"identity":"230762e2-02d6-4f7b-b07b-24a01db72b03","order_by":0,"name":"Ziqi Meng","email":"","orcid":"","institution":"Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Ziqi","middleName":"","lastName":"Meng","suffix":""},{"id":616215251,"identity":"bc10fef5-61d5-474a-a185-4e2d6baf746c","order_by":1,"name":"Jun Qin","email":"","orcid":"","institution":"Qilu Hospital of Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Jun","middleName":"","lastName":"Qin","suffix":""},{"id":616215252,"identity":"d06632db-10c6-4b90-bc55-59fba0c0cab6","order_by":2,"name":"Yujing Sun","email":"","orcid":"","institution":"Qilu Hospital of Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Yujing","middleName":"","lastName":"Sun","suffix":""},{"id":616215253,"identity":"ae69430c-71c0-4962-9428-451787e3ecc5","order_by":3,"name":"Nan Zang","email":"","orcid":"","institution":"Qilu Hospital of Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Nan","middleName":"","lastName":"Zang","suffix":""},{"id":616215254,"identity":"7cbbe6d2-b30d-4f5f-bc1e-ca7a00193dac","order_by":4,"name":"Hulian Huang","email":"","orcid":"","institution":"Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Hulian","middleName":"","lastName":"Huang","suffix":""},{"id":616215255,"identity":"473b1dce-4183-4e08-ba04-ff0870213832","order_by":5,"name":"Xinxu Wang","email":"","orcid":"","institution":"Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Xinxu","middleName":"","lastName":"Wang","suffix":""},{"id":616215256,"identity":"da026d33-df41-4a24-ae2a-c07b783e6200","order_by":6,"name":"Yiming Lu","email":"","orcid":"","institution":"Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Yiming","middleName":"","lastName":"Lu","suffix":""},{"id":616215257,"identity":"e27b32fc-f01e-4651-a606-af6d5eed4b9e","order_by":7,"name":"Jinbo Liu","email":"","orcid":"","institution":"Qilu Hospital of Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Jinbo","middleName":"","lastName":"Liu","suffix":""},{"id":616215258,"identity":"470d30e5-1fcc-4730-9a87-514ef6b830ab","order_by":8,"name":"Li Chen","email":"","orcid":"","institution":"Qilu Hospital of Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Li","middleName":"","lastName":"Chen","suffix":""},{"id":616215259,"identity":"47fcb7ad-b0a3-4b84-ab26-e91a4a179e86","order_by":9,"name":"Xiaoying Zhou","email":"","orcid":"","institution":"Qilu Hospital of Shandong University","correspondingAuthor":false,"prefix":"","firstName":"Xiaoying","middleName":"","lastName":"Zhou","suffix":""},{"id":616215260,"identity":"7a8b8a74-b665-45a2-bd6b-8896eda2f6bb","order_by":10,"name":"Chuan Wang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABFElEQVRIie3OMUsDMRTA8RcK5xLpmoL0vkLkICpV+lUqhesSpFPnTtelxfWgXyJuup0E6RLbNcc5CIXicMNN0kIFE0FwiEfdHPKHe7zj8uMC4PP919DYjCM76LkZPfMEhxCcWUL+Qog9CQcQuniWb7t7GZ611k9iOyQQTjiFaiShOR+7ibqJL2ZKnj7M4zifmotRVVKULiWQl8xJWMZZhBKJRMGZxpYQThvHiTRLz01W5Rfpinz1nu8NCVNDPuqI5tHakGuhcVDYv4A2BNWQri4ZmiWDvlAxK04owVRtho/T5QAT7SatWx5Vu6RzJRZyk5f7y3Y46d+9bkeddjN1E1NAfr5hO7Lv5ZcaVc1Hn8/n8wF8ApwWYthQcFsHAAAAAElFTkSuQmCC","orcid":"","institution":"Qilu Hospital of Shandong University","correspondingAuthor":true,"prefix":"","firstName":"Chuan","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2026-03-17 14:39:01","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9150077/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9150077/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106069075,"identity":"de7f2184-c317-4a72-82fd-cc22929e2d44","added_by":"auto","created_at":"2026-04-03 06:22:31","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":19347,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of serum PROK2 levels among the three groups: A (Healthy Controls), B (T2DM without DKD), and C (T2DM with DKD). Data are presented as mean ±standard error of the mean (SEM).\u003c/p\u003e","description":"","filename":"Fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-9150077/v1/3557c26f3cc83dc0c956a964.png"},{"id":106094385,"identity":"94bd27ab-1294-4408-9314-df1f9fee8880","added_by":"auto","created_at":"2026-04-03 11:42:21","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":23957,"visible":true,"origin":"","legend":"\u003cp\u003eSpearman correlation analysis of correlation between serum PROK2 levels and the urinary albumin-to-creatinine ratio (UACR).\u003c/p\u003e","description":"","filename":"Fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-9150077/v1/f21d5556ecb3d1eed220e5cb.png"},{"id":106069077,"identity":"a7d20728-62a7-4367-b3fe-f2d477294c86","added_by":"auto","created_at":"2026-04-03 06:22:31","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":35777,"visible":true,"origin":"","legend":"\u003cp\u003ePearson correlation analysis of correlation between serum PROK2 levels and the estimated glomerular filtration rate (eGFR).\u003c/p\u003e","description":"","filename":"Fig3.png","url":"https://assets-eu.researchsquare.com/files/rs-9150077/v1/75e3bf92fd00681839433fb4.png"},{"id":106095832,"identity":"ff9f4468-2f24-4682-89f2-23346b6b2cf4","added_by":"auto","created_at":"2026-04-03 11:51:18","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":790110,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9150077/v1/eebdad09-8c19-4650-b60d-5e279d0d7886.pdf"},{"id":106069074,"identity":"858189f0-e54e-4a04-8e90-71d206c4cd05","added_by":"auto","created_at":"2026-04-03 06:22:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":1852571,"visible":true,"origin":"","legend":"","description":"","filename":"Ethics.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9150077/v1/a5dc4f3b545762e88935955e.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Serum Prokineticin 2 Levels Correlate with Diabetic Kidney Disease in Patients with Type 2 Diabetes","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eAccording to the international diabetes federation (IDF) Diabetes Atlas (11th edition), as of 2024, the global prevalence of diabetes mellitus (DM) among individuals aged 20\u0026ndash;79 years has reached 11.1%, corresponding to more than 589\u0026nbsp;million affected individuals worldwide.\u003csup\u003e1\u003c/sup\u003e Data from the global burden of disease (GBD) Study, further indicate that Type 2 diabetes (T2DM) is the predominant form of diseases, accounting for over 90% cases globally.\u003csup\u003e2\u003c/sup\u003e T2DM currently ranks as the eighth leading cause of global disease burden and is projected to become the second leading cause by 2050.\u003csup\u003e3\u003c/sup\u003e Diabetic kidney disease (DKD) is among the most prevalent microvascular complications of DM and represents a major subtype of chronic kidney disease (CKD). Clinically, DKD is characterized by a progressive increase in urinary protein excretion accompanied by a gradual decline in renal function, ultimately leading to end-stage renal disease. This condition places a substantial burden on healthcare systems, worldwide and markedly reduces life expectancy and quality of life.\u003csup\u003e4 5\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe pathogenesis of DKD arises from the synergistic interplay of multiple factors and signaling pathways, and substantial progress has been made in elucidating these mechanisms in recent years. DKD development is driven by a complex network of pathological processes initiated by chronic hyperglycemia. This persistent metabolic disturbance promotes the formation of advanced glycation end products (AGEs) and excessive oxidative stress, which in tern activate key intracellular signaling pathways, including protein kinase C (PKC), mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase/Akt (PI3K/Akt), and nuclear factor-κB (NF-κB), thereby including inflammation and cellular injury.\u003csup\u003e6 7\u003c/sup\u003e Simultaneously, activation of the intrarenal renin-angiotensin-aldosterone system (RAAS) further exacerbates glomerular hemodynamic stress and enhances profibrotic signaling.\u003csup\u003e6\u003c/sup\u003e These processes collectively maintain a chronic inflammatory microenvrionment mediated by cytokines and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, leading to capillary rarefaction and progressive tissue damage.\u003csup\u003e7 8\u003c/sup\u003e Ultimately, sustained inflammation and cellular dysfunction converge to drive renal fibrosis, predominantly through activation of the transforming growth factor-β (TGF-β)/Smad pathway. Emerging evidence further implicates specific macrophage subsets and mediators such as galectin-3 in amplifying fibrotic progression.\u003csup\u003e9 10\u003c/sup\u003e Despite these advances, the precise molecular mechanisms underlying DKD remain incompletely understood due to the disease\u0026rsquo;s complex and multifactorial nature. Accordingly, continued investigation into the biological underpinnings of DKD is essential for the development of effective therapeutic strategies and the advancement of clinical research.\u003c/p\u003e \u003cp\u003eIn recent years, secreted proteins with pleiotropic biological functions have attracted increasing attention for their roles in metabolic disorders and kidney injury, with human prokineticin2 (PROK2), emerging as a molecule of particular interest. PROK2 is a key member of the prokineticin family\u003csup\u003e11\u003c/sup\u003e and was initially identified in the gastrointestinal tract.\u003csup\u003e12\u003c/sup\u003e Recent clinical studies have demonstrated an association between circulating PROK2 levels and metabolic syndrome (MetS).\u003csup\u003e13\u003c/sup\u003e PROK2 functions as an endogenous ligand for two G protein-coupled receptors, prokineticin receptor 1 (PKR1) and prokineticin receptor 2 (PKR2), with a higher binding affinity for PKR1.\u003csup\u003e14\u003c/sup\u003e Activation of PKR1 predominantly triggers cardioprotective and metabolic signaling pathways, including the PI3K/protein kinase B (PI3K/Akt) pathway, which is essential for cell survival and insulin sensitivity.\u003csup\u003e15\u003c/sup\u003e Marie Mortreux and colleagues reported that plasma PROK2 levels were significantly lower in individuals with T2DM compared with normoglycemic subjects; however, this difference was no longer statistically significant after adjustment for body mass index (BMI) and energy intake. In contrast, genetic variants in PROK2 have been linked to incident hyperglycemia (T2DM and impaired fasting glucose), MetS, and obesity.\u003csup\u003e16\u003c/sup\u003e In addition, PKR1 has been shown to play a critical role in kidney development and the maintenance of normal renal function\u003csup\u003e17 18\u003c/sup\u003e and experimental evidence suggests that the PROK2/PKR1 signaling pathway may exert protective effects against DKD in murine models.\u003csup\u003e19\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe existing evidence suggests that PROK2 may play an important role in the pathogenesis of diabetes and DKD. However, direct evidence from human studies examining the associations between PROK2 and T2DM or DKD remains extremely limited. To date, no studies have clearly characterized the serum expression profile of PROK2 in patients, with DKD, nor have they systematically evaluated its relationships with key clinical indicators of renal injury, such as the urinary albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR). In light of these research gaps, the present study aims to comprehensively investigate the associations between serum PROK2 levels and T2DM as well as DKD, thereby providing novel insights into the biological mechanisms underlying DKD pathogenesis.\u003c/p\u003e"},{"header":"METHOD","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eParticipants\u003c/h2\u003e \u003cp\u003e A total of 255 participants were enrolled in this study, including 40 healthy controls and 215 patients with T2DM, all of whom were recruited from Qilu Hospital of Shandong University between May 2024 and November 2025. Eligible participants were aged 35\u0026ndash;80 years and had no severe physical disabilities or psychiatric disorders. Individuals were excluded if they met any of the following criteria: (1) diagnosis of type 1 diabetes or other specific types of diabetes; (2) presence of hepatic or renal diseases unrelated to diabetes; (3) acute or active conditions, including urinary tract infections, diabetic ketoacidosis, or diabetic foot; or (4) a history of malignant tumors. The diagnosis of diabetes was established according to the 2006 world health organization (WHO) criteria.\u003csup\u003e20\u003c/sup\u003e\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eData Collection\u003c/h3\u003e\n\u003cp\u003e Demographic characteristics, clinical parameters, and medical history were systematically obtained for all participants through the electronic medical record system of Qilu Hospital of Shandong University. Collected variables included age, sex, duration of T2DM, BMI, blood pressure (BP), history of hypertension, smoking status, alcohol consumption, glycated hemoglobin (HbA1c), fasting C-peptide, fasting blood glucose (FBG), serum albumin, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglycerides (TG), serum creatinine (Scr), and UACR. The eGFR was calculated using the CKD epidemiology collaboration equation.\u003csup\u003e21\u003c/sup\u003e All laboratory assays were conducted by the Department of Laboratory Medicine at Qilu Hospital ensuring standardized procedures and data reliability. Serum PROK2 concentrations were measured quantitatively using a commercially available enzyme-linked immunosorbent assay kit (EH3582; FineTest, Wuhan, Hubei Province, China).\u003c/p\u003e\n\u003ch3\u003eDefinitions and Grouping Criteria\u003c/h3\u003e\n\u003cp\u003eDKD was defined as a UACR\u0026thinsp;\u0026ge;\u0026thinsp;0.03 g/g or an eGFR\u0026thinsp;\u0026lt;\u0026thinsp;60 mL/min/1.73 m\u0026sup2;, in accordance with the American diabetes association standards of medical care in diabetes\u003csup\u003e22\u003c/sup\u003e and the national kidney foundation kidney disease outcomes quality initiative guidelines.\u003csup\u003e23\u003c/sup\u003e Based on these criteria participants were classified into three groups: (1) healthy controls, defined as individuals without diabetes or albuminuria; (2) patients with T2DM without DKD; and (3) patients with T2DM and DKD.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eThe Kolmogorov-Smirnov test was applied to assess the normality of continuous variables and homogeneity of variance was evalutaed using the F-test. Continuous variables are expressed as the mean\u0026plusmn;standard deviation for normally distributed data or as the median (interquartile range) for non-normally distributed data, whlie categorical variables are presented as counts (percentages). Between group differences were analyzed using one-way analysis of variance followed by the least significant difference post hoc test for normally distributed continuous variables, the Kruskal-Wallis test for non-normally distributed continuous variables, and the Pearson chi-square(χ2)test for categorical variables. Binary logistic regression models were constructed to evaluate the association between serum PROK2 levels and the risks of T2DM and DKD. Correlation analyses were performed to examine the relationships between serum PROK2 levels and renal function indices, including UACR and eGFR. A two-sided \u003cem\u003ep\u003c/em\u003e value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant. All statiscal analyses were conducted using SPSS software (version 25.0; IBM Corp., Armonk, NY, USA), and graphical representations were generated using GraphPad Prism (version 10.1; GraphPad Software, San Diego, CA, USA).\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eClinical characteristics and serum PROK2 levels of participants in different groups\u003c/h2\u003e \u003cp\u003eCompared with patients with T2DM without DKD, those in the DKD group exhibited significantly higher BP, UACR, HbA1c, FBG, and a greater proportion of angiotensin-converting enzyme inhibitor (ACEI)/angiotensin II receptor blocker (ARB) and insulin use. In contrast, eGFR serum albumin levels, and the proportion of metformin use were significantly lower in the DKD group (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). In addition, serum PROK2 concentrations were reduced in patients with T2DM compared with healthy controls and were lowest in patients with DKD (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic and biochemical parameters of the study population in different groups.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003en\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHealthy controls\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT2DM without DKD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT2DM with DKD\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e115\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge(years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e59.58\u0026thinsp;\u0026plusmn;\u0026thinsp;3.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57.91\u0026thinsp;\u0026plusmn;\u0026thinsp;8.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e58.66\u0026thinsp;\u0026plusmn;\u0026thinsp;9.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale, n(%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21(52.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e65(56.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e62(62)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI(kg/m2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24.32\u0026thinsp;\u0026plusmn;\u0026thinsp;3.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.11\u0026thinsp;\u0026plusmn;\u0026thinsp;4.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.06\u0026thinsp;\u0026plusmn;\u0026thinsp;4.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDrinking, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32(27.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e29(29)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmoking, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28(24.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24(24)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6(15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e56(48.7)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71(71)*\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes duration (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10(6, 18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16(8.25, 20)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSBP (mm Hg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e123.78\u0026thinsp;\u0026plusmn;\u0026thinsp;11.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e131.86\u0026thinsp;\u0026plusmn;\u0026thinsp;17.26*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e139.91\u0026thinsp;\u0026plusmn;\u0026thinsp;20.90*\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDBP (mm Hg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e76.45\u0026thinsp;\u0026plusmn;\u0026thinsp;8.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e77.59\u0026thinsp;\u0026plusmn;\u0026thinsp;10.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81.01\u0026thinsp;\u0026plusmn;\u0026thinsp;11.93*\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTC (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.07\u0026thinsp;\u0026plusmn;\u0026thinsp;0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.19\u0026thinsp;\u0026plusmn;\u0026thinsp;1.15*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.46\u0026thinsp;\u0026plusmn;\u0026thinsp;1.37*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLDL-C (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.99\u0026thinsp;\u0026plusmn;\u0026thinsp;0.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.46\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.53\u0026thinsp;\u0026plusmn;\u0026thinsp;1.01*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHDL-C (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.46\u0026thinsp;\u0026plusmn;\u0026thinsp;0.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.32*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.37*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTG (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.17(0.95, 1.55)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.20(0.89, 1.98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.29(0.95, 2.18)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum albumin (g/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e46.24\u0026thinsp;\u0026plusmn;\u0026thinsp;1.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42.41\u0026thinsp;\u0026plusmn;\u0026thinsp;3.16*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e41.21\u0026thinsp;\u0026plusmn;\u0026thinsp;4.74*\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eeGFR (mL/min/1.73m\u003csup\u003e2\u003c/sup\u003e )\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e93.72\u0026thinsp;\u0026plusmn;\u0026thinsp;11.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e99.88\u0026thinsp;\u0026plusmn;\u0026thinsp;11.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.15\u0026thinsp;\u0026plusmn;\u0026thinsp;26.45*\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUACR(g(Alb)/g(Cr))\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00(0.00, 0.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01(0.01, 0.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.09(0.04, 0.30) *\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHbA1c (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.66\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.22\u0026thinsp;\u0026plusmn;\u0026thinsp;1.69*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.04*\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFBG (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.91\u0026thinsp;\u0026plusmn;\u0026thinsp;2.00*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.70\u0026thinsp;\u0026plusmn;\u0026thinsp;3.26*\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFasting C-peptide (ng/mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.36\u0026thinsp;\u0026plusmn;\u0026thinsp;0.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.65\u0026thinsp;\u0026plusmn;\u0026thinsp;1.10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eACEI or ARB treatment, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23(20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e33(33)\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMetformin treatment, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e106(92.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e74(74)\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSGLT2i treatment, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42(36.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e27(27)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGLP-1 treatment, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9(7.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6(6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInsulin therapy, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN/C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52(45.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e67(67)\u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e* \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 compared with the healthy control group.\u003c/p\u003e \u003cp\u003e\u0026dagger; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 for comparison between T2DM patients with DKD and without DKD groups.\u003c/p\u003e \u003cp\u003eBMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; TC, total cholesterol; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; TG, triglyceride; eGFR, estimated glomerular filtration rate; UACR, urinary albumin-to-creatinine ratio; HbA1c, glycated hemoglobin; FBG, fasting blood glucose; ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin II receptor blocker; SGLT2i, sodium-glucose cotransporter 2 inhibitor; GLP-1 RA, glucagon-like peptide-1 receptor agonist.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eCorrelation analysis between serum PROK2 levels and T2DM\u003c/h3\u003e\n\u003cp\u003eTo elucidate the association between serum PROK2 levels and T2DM, binary logistic regression analyses were performed (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The results indicated that serum PROK2 levels were independently associated with the presence of T2DM, even after adjustment for multiple potential confounders, including sex, age, BMI, systolic BP (SBP), TG, LDL-C and eGFR (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBinary logistic regression analysis of the relationship between serum PROK2 levels and T2DM\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eModel 1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOR (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.565 (0.403 to 0.792)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModel 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.506 (0.353 to 0.727)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModel 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.492 (0.322 to 0.751)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eModel 1: Unadjusted.\u003c/p\u003e \u003cp\u003eModel 2: Adjusted for sex and age.\u003c/p\u003e \u003cp\u003eModel 3: Adjusted for sex, age, BMI, systolic blood pressure, triglycerides, low-density lipoprotein cholesterol and eGFR.\u003c/p\u003e\n\u003ch3\u003eCorrelation analysis between serum PROK2 levels and DKD\u003c/h3\u003e\n\u003cp\u003eBinary logistic regression analysis was performed to examine the association between serum PROK2 levels and the presence of DKD (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The findings demonstrated that serum PROK2 levels remains significantly associated with DKD, after adjustment for a comprehensive set of potential confounders, including sex, age, BMI, SBP, serum albumin, HbA1c, fasting C-peptide, TG, LDL-C, smoking status, alcohol consumption history, duration of diabetes, and the use of ACEIs/ARBs and SGLT2 inhibitors. In addition, the relationships between serum PROK2 levels and renal function parameters were further explore across all participants. Spearman correlation analysis revealed a significant inverse association between serum PROK2 levels and UACR (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;\u0026thinsp;0.212, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0007) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Consistently, Pearson correlation analysis demonstrated a significantly positive correlation between serum PROK2 levels and eGFR (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.271, \u003cem\u003eP\u003c/em\u003e\u0026lt;0.0001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBinary logistic regression analysis of the association between serum PROK2 levels and DKD in patients with T2DM.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eModel 1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOR (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.679 (0.496 to 0.928)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.015\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModel 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.654 (0.472 to 0.906)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.011\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModel 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.679 (0.465 to 0.992)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.046\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eModel 1: Unadjusted.\u003c/p\u003e \u003cp\u003eModel 2: Adjusted for sex and age.\u003c/p\u003e \u003cp\u003eModel 3: Adjusted for sex, age, BMI, systolic blood pressure, serum albumin, HbA1c, fasting C-peptide, triglyceride, low-density lipoprotein cholesterol, smoking history, history of alcohol consumption, duration of diabetes, use of ACEIs/ARBs and use of SGLT2i.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThe present study systematically examined the associations between serum PROK2 levels and the presence of T2DM and DKD. The results demonstrated that serum PROK2 concentrations were significantly reduced in patients with T2DM compared with healthy controls, with the most pronounced decrease observed in patients with DKD. Further multivariate analyses revealed that serum PROK2 levels were independently associated with both T2DM and DKD. To our knowledge, this study is the first to provide clinical evidence linking circulating PROK2 levels to renal injury in patients with T2DM.\u003c/p\u003e \u003cp\u003ePROK2, a secreted protein with pleiotropic biological functions, has been increasingly recognized as an important component of metabolic regulatory networks.\u003csup\u003e24\u0026ndash;26\u003c/sup\u003e Clinical studies have demonstrated that PROK2 is closely associated with the development and progression of DM and MetS.\u003csup\u003e16\u003c/sup\u003e Population-based cohort studies have shown that plasma PROK2 concentrations are significantly lower in patients with T2DM than in individuals with normoglycemia, a finding consistent with our results. However, this association became non-significant after adjustment for BMI or caloric intake, suggesting that the relationship between PROK2 and DM may be partially mediated by obesity.\u003csup\u003e16\u003c/sup\u003e In contrast, studies in obese children have reported significantly elevated serum PROK2 levels compared with those in normal-weight children, with PROK2 positively correlated with BMI, fasting insulin levels, and the homeostatic model assessment of insulin resistance. These findings indicate that PROK2 expression exhibits age- and metabolic state-dependent heterogeneity.\u003csup\u003e27\u003c/sup\u003e\u003c/p\u003e \u003cp\u003ePROK2 plays a multifaceted role in metabolic regulation and the pathogenesis of diabetes through diverse and integrated mechanisms. Evidence from multiple lines of research highlights its central involvement in energy homeostasis, glucose metabolism, appetite regulation, and protection against diabetic organ damage. As a key modulator of systemic energy balance, PROK2 exerts its biological effects by binding to the G protein-coupled receptors PKR1 and PKR2, thereby activating downstream signaling pathways that regulate glucose utilization and metabolic homeostasis. In humans, genetic polymorphisms in the PROK2 gene have been linked to obesity and diabetes, underscoring its physiological importance in metabolic regulation.\u003csup\u003e16 25\u003c/sup\u003e At the peripheral level, the PROK2/PKR1 signaling pathway promotes energy expenditure by upregulating uncoupling protein 1 expression in brown adipose tissue, facilitating adipose tissue browning and thermogenesis.\u003csup\u003e25\u003c/sup\u003e Additionally, this pathway suppresses preadipocyte proliferation and differentiation, thereby limiting adipose tissue expansion and mitigating obesity development.\u003csup\u003e28\u003c/sup\u003e Consistently, peripheral administration of PROK2 has been shown to reduce body weight in diet-induced obese mice, in part through mechanisms resembling adiponectin signaling.\u003csup\u003e29\u003c/sup\u003e Within the central nervous system, PROK2 functions as a potent anorexigenic neuropeptide. Intracerebroventricular administration of PROK2 markedly suppresses food intake in rodents, whereas neutralization of endogenous PROK2 leads to increased appetite.\u003csup\u003e30 31\u003c/sup\u003e Moreover, peripherally administered PROK2 can access brainstem circuits to exert appetite-suppressing and weight-reducing effects.\u003csup\u003e29\u003c/sup\u003e Beyond its role in metabolic regulation, PROK2 signaling has also been implicated in the development and potential treatment of diabetic complications, particularly diabetic cardiomyopathy. In diabetic hearts, expression levels of PROK2 and its receptors are significantly reduced, accompanied by impaired AKT/GSK3β signaling. Both metformin treatment and exogenous PROK2 administration confer protection against high glucose-induced cardiomyocyte injury through activation of the PROK2/PKR1/AKT axis, effects that are abolished by PKR1 or AKT inhibition.\u003csup\u003e32\u003c/sup\u003e These findings are consistent with earlier observations demonstrating that PROK2/PKR1 signaling mitigates the progression of diabetes, obesity, and associated cardiovascular disorders.\u003csup\u003e28\u003c/sup\u003e Collectively, these studies indicate that PROK2 regulates energy metabolism and glucose homeostasis through coordinated actions on adipose tissue remodeling, appetite control, and protection against diabetes-related organ damage. Our findings further extend this framework by providing clinical evidence that reduced circulating PROK2 levels are closely associated with the development of diabetes, supporting the translational relevance of PROK2 signaling in human metabolic disease.\u003c/p\u003e \u003cp\u003eDKD, one of the most prevalent microvascular complications of DM, is characterized by a complex and multifactorial pathogenesis arising from the interplay of genetic susceptibility, metabolic dysregulation, and environmental influences. The disease process is initiated by chronic hyperglycemia, which triggers a network of interconnected pathological pathways that progressively drive renal dysfunction and ultimately renal failure.\u003csup\u003e33\u003c/sup\u003e Early metabolic disturbances, including the accumulation of AGEs and activation of PKC, directly impair glomerular and tubular structures.\u003csup\u003e34 35\u003c/sup\u003e These metabolic insults are further exacerbated by hemodynamic alterations and activation of the intrarenal RAAS, leading to glomerular hypertension and enhanced pro-fibrotic signaling.\u003csup\u003e36 37\u003c/sup\u003e Oxidative stress represents a central pathogenic hub in DKD, largely driven by mitochondrial dysfunction and excessive reactive oxygen species production. This oxidative milieu sustains chronic inflammation through the activation of key transcriptional regulators, including NF-κB and TGF-β signaling pathways.\u003csup\u003e38 39\u003c/sup\u003e Collectively, these metabolic, hemodynamic, oxidative, and inflammatory processes converge to induce podocyte injury, excessive extracellular matrix deposition, and progressive tubulointerstitial fibrosis. The resulting structural and functional deterioration manifests clinically as persistent proteinuria and a gradual decline in glomerular filtration rate.\u003csup\u003e35 40\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe precise mechanistic role of PROK2 in the pathogenesis of DKD has not yet been fully elucidated. Nevertheless, accumulating evidence indicates that the PROK2/PKR1 signaling axis plays a critical role in kidney development and the maintenance of renal structural integrity. Conditional disruption of the PKR1 gene in mice results in marked renal abnormalities, including tubular dilation, reduced glomerular capillary density, increased urinary phosphate excretion, and overt proteinuria.\u003csup\u003e18\u003c/sup\u003e In vitro studies further demonstrate that PROK2, through activation of PKR1, promotes the differentiation of epicardin-positive renal progenitor cells into endothelial and smooth muscle cells, suggesting a pivotal role for PROK2/PKR1 signaling in renal angiogenesis and neovascularization.\u003csup\u003e18\u003c/sup\u003e Consistent with these findings, endothelium-specific PKR1 knockout mice (ec-PKR1⁻/⁻) exhibit severe renal structural disorders characterized by compact, fibrotic glomeruli and elevated phosphate excretion, highlighting the importance of endothelial PKR1 signaling in preserving glomerular architecture\u003csup\u003e41\u003c/sup\u003e Additional mechanistic studies have identified PKR1 as a crucial modulator of mesenchymal-epithelial transition (MET), a key process in nephron formation during kidney development, mediated through NFATc3-dependent signaling pathways.\u003csup\u003e17\u003c/sup\u003e Collectively, these findings suggest that the PROK2/PKR1 pathway exerts a protective role in renal development and vascular homeostasis. In the context of DKD, this protective function may be compromised, as reflected by the significantly lower serum PROK2 levels observed in patients with DKD in the present study. Supporting this hypothesis, recent experimental evidence demonstrates that activation of the PROK2/PKR1 signaling pathway mediates the renoprotective effects of geniposide in DKD mouse models, further implicating this axis in kidney protection under diabetic conditions.\u003csup\u003e19\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThis study has several limitations that should be acknowledged when interpreting the findings and guiding future research. First, the cross-sectional design captures exposure and outcome variables at a single time point; consequently, the absence of longitudinal follow-up precludes characterization of dynamic changes in serum PROK2 levels during DKD progression and limits the ability to establish causal relationships. Second, although a robust clinical association between serum PROK2 levels and DKD was observed, the underlying molecular mechanisms through which PROK2 may exert renoprotective effects were not directly investigated. While existing evidence suggests that the PROK2/PKR signaling pathway is involved in the regulation of inflammation and fibrosis,\u003csup\u003e42 43\u003c/sup\u003e its activation status and downstream signaling events in the context of diabetic renal injury warrant further mechanistic validation using experimental models. Third, all participants in this study were of Chinese ethnicity, which may restrict the generalizability of the results to other populations and underscores the need for validation in ethnically diverse cohorts.\u003c/p\u003e \u003cp\u003eIn conclusion, through rigorous clinical analysis, this study provides the first evidence that lower serum PROK2 levels are independently associated with T2DM and DKD, correlating with key markers of renal impairment. This supports the hypothesis that PROK2 may play an important role in the pathogenesis of T2DM and DKD. However, this work primarily establishes a clinical association; the specific molecular mechanisms, signaling pathways, and full clinical translational value of PROK2 in DKD demand in-depth exploration. Future research must employ an integrated strategy combining basic science and clinical studies to define the prognostic utility of PROK2, establish its functional role in relevant models, and evaluate the feasibility of therapeutic targeting, thereby paving the way for novel diagnostic and therapeutic approaches in DKD.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eCONTRIBUTORS\u003c/h2\u003e\n\u003cp\u003eZM and JQ are joint first authors. CW obtained funding. ZM, JL, and LC designed the study. LY, NZ, YS, XZ, HH, XW and ZM collected the data. ZM, CW, and XZ analyzed the data. ZM drafted the manuscript. CW and LC contributed to the interpretation of the results and critical revision of the manuscript for important intellectual content and approved the final version of the manuscript. All authors have read and approved the final manuscript. CW and XZ are the study guarantors.\u003c/p\u003e\n\u003ch2\u003eDATA AVAILABLILITY\u003c/h2\u003e\n\u003cp\u003eDataset used in this study is available upon reasonable request to the corresponding author via [email protected].\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eno support from any organization for the submitted work; no financial relationships with any organization that might have an interest in the submitted work in the previous three years, no other relationships or activities that could appear to have influenced the submitted work.\u003c/p\u003e\n\u003ch2\u003ePatient consent for publication\u003c/h2\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003ch2\u003eEthics approval\u003c/h2\u003e\n\u003cp\u003eThis study involves human participants and was conducted in accordance with the ethical principles of the Chinese Measures for the Ethical Review of Biomedical Research Involving Humans, the WMA Declaration of Helsinki, and the CIOMS International Ethical Guidelines for Biomedical Research Involving Human Subjects. The study was approved by the Ethics Committee of Qilu Hospital of Shandong University (Ethics Approval No. KYLL-202506-112). All participants provided informed consent before taking part in the study.\u003c/p\u003e\n\u003ch2\u003eFUNDING\u003c/h2\u003e\n\u003cp\u003eThis study was supported by grants from the Natural Science Foundation of Shandong Province (ZR2023MH005).\u003c/p\u003e\n\u003ch2\u003eACKNOWLEDGEMENTS\u003c/h2\u003e\n\u003cp\u003eWe thank all participants involved in this study.\u003c/p\u003e\n\u003ch2\u003eData Availability\u003c/h2\u003e\n\u003cp\u003eDataset used in this study is available upon reasonable request to the corresponding author via [[email protected]](mailto:[email protected]) .\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eGenitsaridi I, Salpea P, Salim A, et al. 11th edition of the IDF Diabetes Atlas: global, regional, and national diabetes prevalence estimates for 2024 and projections for 2050. \u003cem\u003eLancet Diabetes Endocrinol\u003c/em\u003e 2025 doi: 10.1016/s2213-8587(25)00299-2 [published Online First: 20251215]\u003c/li\u003e\n\u003cli\u003eGlobal, regional, and national burden of diabetes from 1990 to 2021, with projections of prevalence to 2050: a systematic analysis for the Global Burden of Disease Study 2021. \u003cem\u003eLancet\u003c/em\u003e 2023;402(10397):203\u0026ndash;34. doi: 10.1016/s0140-6736(23)01301-6 [published Online First: 20230622]\u003c/li\u003e\n\u003cli\u003e(IHME) IfHMaE. GBD Foresight Visualization: IHME,University of Washington; 2024 [Available from: https://vizhub.healthdata.org/gbd-foresight accessed 2026-01-05.\u003c/li\u003e\n\u003cli\u003eNaaman SC, Bakris GL. Diabetic Nephropathy: Update on Pillars of Therapy Slowing Progression. \u003cem\u003eDiabetes Care\u003c/em\u003e 2023;46(9):1574\u0026ndash;86. doi: 10.2337/dci23-0030\u003c/li\u003e\n\u003cli\u003eKriz W, L\u0026ouml;wen J, Gr\u0026ouml;ne HJ. The complex pathology of diabetic nephropathy in humans. \u003cem\u003eNephrol Dial Transplant\u003c/em\u003e 2023;38(10):2109\u0026ndash;19. doi: 10.1093/ndt/gfad052\u003c/li\u003e\n\u003cli\u003ePasupulati AK, Nagati V, Paturi ASV, et al. Non-enzymatic glycation and diabetic kidney disease. \u003cem\u003eVitam Horm\u003c/em\u003e 2024;125:251\u0026ndash;85. doi: 10.1016/bs.vh.2024.01.002 [published Online First: 20240206]\u003c/li\u003e\n\u003cli\u003eWang N, Zhang C. Oxidative Stress: A Culprit in the Progression of Diabetic Kidney Disease. \u003cem\u003eAntioxidants (Basel)\u003c/em\u003e 2024;13(4) doi: 10.3390/antiox13040455 [published Online First: 20240412]\u003c/li\u003e\n\u003cli\u003eDu H, Wang Y, Zhu Y, et al. MiR-29b Alleviates High Glucose-induced Inflammation and Apoptosis in Podocytes by Down-regulating PRKAB2. \u003cem\u003eEndocr Metab Immune Disord Drug Targets\u003c/em\u003e 2024;24(8):981\u0026ndash;90. doi: 10.2174/0118715303267375231204103200\u003c/li\u003e\n\u003cli\u003eChen Y, Jiang Q, Xing X, et al. Macrophage Derived Galectin-3 Promotes Renal Fibrosis and Diabetic Kidney Disease by Enhancing TGF\u0026beta;1 Signaling. \u003cem\u003eAdv Sci (Weinh)\u003c/em\u003e 2025;12(35):e04032. doi: 10.1002/advs.202504032 [published Online First: 20250813]\u003c/li\u003e\n\u003cli\u003eChetty S, Yarani R, Swaminathan G, et al. Umbilical cord mesenchymal stromal cells-from bench to bedside. \u003cem\u003eFront Cell Dev Biol\u003c/em\u003e 2022;10:1006295. doi: 10.3389/fcell.2022.1006295 [published Online First: 20221012]\u003c/li\u003e\n\u003cli\u003eNegri L, Lattanzi R, Giannini E, et al. Bv8, the amphibian homologue of the mammalian prokineticins, modulates ingestive behaviour in rats. \u003cem\u003eBr J Pharmacol\u003c/em\u003e 2004;142(1):181\u0026ndash;91. doi: 10.1038/sj.bjp.0705686 [published Online First: 20040405]\u003c/li\u003e\n\u003cli\u003eLi M, Bullock CM, Knauer DJ, et al. Identification of two prokineticin cDNAs: recombinant proteins potently contract gastrointestinal smooth muscle. \u003cem\u003eMol Pharmacol\u003c/em\u003e 2001;59(4):692\u0026ndash;8. doi: 10.1124/mol.59.4.692\u003c/li\u003e\n\u003cli\u003eWang Y, Guo X, Ma H, et al. Prokineticin-2 is associated with metabolic syndrome in a middle-aged and elderly Chinese population. \u003cem\u003eLipids Health Dis\u003c/em\u003e 2016;15:1. doi: 10.1186/s12944-015-0172-5 [published Online First: 20160105]\u003c/li\u003e\n\u003cli\u003eChen J, Kuei C, Sutton S, et al. Identification and pharmacological characterization of prokineticin 2 beta as a selective ligand for prokineticin receptor 1. \u003cem\u003eMol Pharmacol\u003c/em\u003e 2005;67(6):2070\u0026ndash;6. doi: 10.1124/mol.105.011619 [published Online First: 20050316]\u003c/li\u003e\n\u003cli\u003eBoulberdaa M, Urayama K, Nebigil CG. Prokineticin receptor 1 (PKR1) signalling in cardiovascular and kidney functions. \u003cem\u003eCardiovasc Res\u003c/em\u003e 2011;92(2):191\u0026ndash;8. doi: 10.1093/cvr/cvr228 [published Online First: 20110819]\u003c/li\u003e\n\u003cli\u003eMortreux M, Foppen E, Denis RG, et al. New roles for prokineticin 2 in feeding behavior, insulin resistance and type 2 diabetes: Studies in mice and humans. \u003cem\u003eMol Metab\u003c/em\u003e 2019;29:182\u0026ndash;96. doi: 10.1016/j.molmet.2019.08.016 [published Online First: 20190828]\u003c/li\u003e\n\u003cli\u003eArora H, Boulberdaa M, Qureshi R, et al. Prokineticin receptor 1 is required for mesenchymal-epithelial transition in kidney development. \u003cem\u003eFaseb j\u003c/em\u003e 2016;30(8):2733\u0026ndash;40. doi: 10.1096/fj.201600181R [published Online First: 20160415]\u003c/li\u003e\n\u003cli\u003eBoulberdaa M, Turkeri G, Urayama K, et al. Genetic inactivation of prokineticin receptor-1 leads to heart and kidney disorders. \u003cem\u003eArterioscler Thromb Vasc Biol\u003c/em\u003e 2011;31(4):842\u0026ndash;50. doi: 10.1161/atvbaha.110.222323 [published Online First: 20110127]\u003c/li\u003e\n\u003cli\u003eDai SJ, Zhang QY, Lan Q, et al. [PK2/PKR1 signaling pathway participates in geniposide protection against diabetic nephropathy in mice]. \u003cem\u003eZhongguo Zhong Yao Za Zhi\u003c/em\u003e 2022;47(6):1611\u0026ndash;17. doi: 10.19540/j.cnki.cjcmm.20211122.401\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia 2006 [Available from: https://iris.who.int/handle/10665/43588.\u003c/li\u003e\n\u003cli\u003eLevey AS, Stevens LA, Schmid CH, et al. A new equation to estimate glomerular filtration rate. \u003cem\u003eAnn Intern Med\u003c/em\u003e 2009;150(9):604\u0026ndash;12. doi: 10.7326/0003-4819-150-9-200905050-00006\u003c/li\u003e\n\u003cli\u003eChronic Kidney Disease and Risk Management: Standards of Care in Diabetes-2026. \u003cem\u003eDiabetes Care\u003c/em\u003e 2026;49(Supplement_1):S246\u0026ndash;s60. doi: 10.2337/dc26-S011\u003c/li\u003e\n\u003cli\u003eKDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. \u003cem\u003eKidney Int\u003c/em\u003e 2024;105(4s):S117\u0026ndash;s314. doi: 10.1016/j.kint.2023.10.018\u003c/li\u003e\n\u003cli\u003eVincenzi M, Nebigil CG. Uncovering the role of prokineticin pathway on Epicardial Adipose Tissue (EAT) development and EAT-associated cardiomyopathy. \u003cem\u003eTrends Cardiovasc Med\u003c/em\u003e 2025;35(5):328\u0026ndash;38. doi: 10.1016/j.tcm.2025.02.006 [published Online First: 20250213]\u003c/li\u003e\n\u003cli\u003eMagnan C, Migrenne-Li S. Pleiotropic effects of prokineticin 2 in the control of energy metabolism. \u003cem\u003eBiochimie\u003c/em\u003e 2021;186:73\u0026ndash;81. doi: 10.1016/j.biochi.2021.04.009 [published Online First: 20210429]\u003c/li\u003e\n\u003cli\u003eNebigil CG. Prokineticin Is a New Linker between Obesity and Cardiovascular Diseases. \u003cem\u003eFront Cardiovasc Med\u003c/em\u003e 2017;4:20. doi: 10.3389/fcvm.2017.00020 [published Online First: 20170412]\u003c/li\u003e\n\u003cli\u003eWang H, Jia Y, Yu X, et al. Circulating Prokineticin 2 Levels Are Increased in Children with Obesity and Correlated with Insulin Resistance. \u003cem\u003eInt J Endocrinol\u003c/em\u003e 2021;2021:6630102. doi: 10.1155/2021/6630102 [published Online First: 20210404]\u003c/li\u003e\n\u003cli\u003eSzatkowski C, Vallet J, Dormishian M, et al. Prokineticin receptor 1 as a novel suppressor of preadipocyte proliferation and differentiation to control obesity. \u003cem\u003ePLoS One\u003c/em\u003e 2013;8(12):e81175. doi: 10.1371/journal.pone.0081175 [published Online First: 20131204]\u003c/li\u003e\n\u003cli\u003eBeale K, Gardiner JV, Bewick GA, et al. Peripheral administration of prokineticin 2 potently reduces food intake and body weight in mice via the brainstem. \u003cem\u003eBr J Pharmacol\u003c/em\u003e 2013;168(2):403\u0026ndash;10. doi: 10.1111/j.1476-5381.2012.02191.x\u003c/li\u003e\n\u003cli\u003eYilmaz U, Tanbek K. Intracerebroventricular prokineticin 2 infusion may play a role on the hypothalamus-pituitary-thyroid axis and energy metabolism. \u003cem\u003ePhysiol Behav\u003c/em\u003e 2024;283:114601. doi: 10.1016/j.physbeh.2024.114601 [published Online First: 20240603]\u003c/li\u003e\n\u003cli\u003eGardiner JV, Bataveljic A, Patel NA, et al. Prokineticin 2 is a hypothalamic neuropeptide that potently inhibits food intake. \u003cem\u003eDiabetes\u003c/em\u003e 2010;59(2):397\u0026ndash;406. doi: 10.2337/db09-1198 [published Online First: 20091123]\u003c/li\u003e\n\u003cli\u003eYang Z, Wang M, Zhang Y, et al. Metformin Ameliorates Diabetic Cardiomyopathy by Activating the PK2/PKR Pathway. \u003cem\u003eFront Physiol\u003c/em\u003e 2020;11:425. doi: 10.3389/fphys.2020.00425 [published Online First: 20200519]\u003c/li\u003e\n\u003cli\u003eZhang X, Zhang J, Ren Y, et al. Unveiling the pathogenesis and therapeutic approaches for diabetic nephropathy: insights from panvascular diseases. \u003cem\u003eFront Endocrinol (Lausanne)\u003c/em\u003e 2024;15:1368481. doi: 10.3389/fendo.2024.1368481 [published Online First: 20240222]\u003c/li\u003e\n\u003cli\u003eHu Q, Chen Y, Deng X, et al. Diabetic nephropathy: Focusing on pathological signals, clinical treatment, and dietary regulation. \u003cem\u003eBiomed Pharmacother\u003c/em\u003e 2023;159:114252. doi: 10.1016/j.biopha.2023.114252 [published Online First: 20230113]\u003c/li\u003e\n\u003cli\u003eWu T, Ding L, Andoh V, et al. The Mechanism of Hyperglycemia-Induced Renal Cell Injury in Diabetic Nephropathy Disease: An Update. \u003cem\u003eLife (Basel)\u003c/em\u003e 2023;13(2) doi: 10.3390/life13020539 [published Online First: 20230215]\u003c/li\u003e\n\u003cli\u003eR\u0026uuml;ster C, Wolf G. Renin-angiotensin-aldosterone system and progression of renal disease. \u003cem\u003eJ Am Soc Nephrol\u003c/em\u003e 2006;17(11):2985\u0026ndash;91. doi: 10.1681/asn.2006040356 [published Online First: 20061011]\u003c/li\u003e\n\u003cli\u003eRahimi Z. The Role of Renin Angiotensin Aldosterone System Genes in Diabetic Nephropathy. \u003cem\u003eCan J Diabetes\u003c/em\u003e 2016;40(2):178\u0026ndash;83. doi: 10.1016/j.jcjd.2015.08.016 [published Online First: 20151124]\u003c/li\u003e\n\u003cli\u003eYaribeygi H, Atkin SL, Sahebkar A. Interleukin-18 and diabetic nephropathy: A review. \u003cem\u003eJ Cell Physiol\u003c/em\u003e 2019;234(5):5674\u0026ndash;82. doi: 10.1002/jcp.27427 [published Online First: 20181111]\u003c/li\u003e\n\u003cli\u003eJin Q, Liu T, Qiao Y, et al. Oxidative stress and inflammation in diabetic nephropathy: role of polyphenols. \u003cem\u003eFront Immunol\u003c/em\u003e 2023;14:1185317. doi: 10.3389/fimmu.2023.1185317 [published Online First: 20230721]\u003c/li\u003e\n\u003cli\u003eIhim SA, Abubakar SD, Zian Z, et al. Interleukin-18 cytokine in immunity, inflammation, and autoimmunity: Biological role in induction, regulation, and treatment. \u003cem\u003eFront Immunol\u003c/em\u003e 2022;13:919973. doi: 10.3389/fimmu.2022.919973 [published Online First: 20220811]\u003c/li\u003e\n\u003cli\u003eDormishian M, Turkeri G, Urayama K, et al. Prokineticin receptor-1 is a new regulator of endothelial insulin uptake and capillary formation to control insulin sensitivity and cardiovascular and kidney functions. \u003cem\u003eJ Am Heart Assoc\u003c/em\u003e 2013;2(5):e000411. doi: 10.1161/jaha.113.000411 [published Online First: 20131023]\u003c/li\u003e\n\u003cli\u003eZhao Y, Wu J, Wang X, et al. Prokineticins and their G protein-coupled receptors in health and disease. \u003cem\u003eProg Mol Biol Transl Sci\u003c/em\u003e 2019;161:149\u0026ndash;79. doi: 10.1016/bs.pmbts.2018.09.006 [published Online First: 20181024]\u003c/li\u003e\n\u003cli\u003eLattanzi R, Severini C, Maftei D, et al. The Role of Prokineticin 2 in Oxidative Stress and in Neuropathological Processes. \u003cem\u003eFront Pharmacol\u003c/em\u003e 2021;12:640441. doi: 10.3389/fphar.2021.640441 [published Online First: 20210301]\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-endocrine-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bend","sideBox":"Learn more about [BMC Endocrine Disorders](http://bmcendocrdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bend/default.aspx","title":"BMC Endocrine Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Prokineticin 2, Diabetic Kidney Disease, Urinary Albumin-to-Creatinine Ratio, Estimated Glomerular Filtration Rate","lastPublishedDoi":"10.21203/rs.3.rs-9150077/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9150077/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eIntroduction:\u003c/h2\u003e \u003cp\u003eProkineticin 2 (PROK2) is a secreted protein, that plays a critical role in the circadian regulation of energy homeostasis. However, its association with type 2 diabetes mellitus (T2DM) and diabetes-related complication remains poorly understand. This study aimed to investigate the relationship between serum PROK2 levels, T2DM and diabetic kidney disease (DKD).\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003e A total of 255 participants were enrolled, including 40 healthy controls and 215 patients with T2DM. DKD was defined as a urinary albumin-to-creatinine ratio (UACR)\u0026thinsp;\u0026ge;\u0026thinsp;0.03 g/g, or an estimated glomerular filtration rate (eGFR)\u0026thinsp;\u0026lt;\u0026thinsp;60 mL/min/1.73m\u0026sup2;. Serum PROK2 concentrations were quantified using enzyme-linked immunosorbent assay. Binary logistic regression models were applied to evaluate the associations between PROK2 levels and the risks of T2DM and DKD. Correlation analyses were performed to assess the relationships between PROK2 and renal function indicators, including UACR and eGFR.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eSerum PROK2 levels differed significantly among the study groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), with the lowest concentrations observed in patients with DKD. After adjustment for potential confounders, higher serum PROK2 levels were independently associated with a lower risk of T2DM (odds ratio [OR]\u0026thinsp;=\u0026thinsp;0.492, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001) and DKD (OR\u0026thinsp;=\u0026thinsp;0.679, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.046). Furthermore, PROK2 levels were negatively correlated with UACR (\u003cem\u003er\u003c/em\u003e =\u0026ndash;0.212, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0007) and positively correlated with eGFR (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.271, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.0001).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eSerum PROK2 levels are significantly reduced in patients with T2DM, particularly among those with DKD. These findings suggest that PROK2 may serve as a novel circulating biomarker for assessing renal impairment in individuals with T2DM.\u003c/p\u003e","manuscriptTitle":"Serum Prokineticin 2 Levels Correlate with Diabetic Kidney Disease in Patients with Type 2 Diabetes","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-03 06:22:23","doi":"10.21203/rs.3.rs-9150077/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"234710104340088016181383123267760250184","date":"2026-04-01T21:29:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"291440148297212762636188913646651913804","date":"2026-04-01T18:25:10+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-31T11:30:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"6741389671247003618158327668088915171","date":"2026-03-31T06:24:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"96449692382950598799870990140722614880","date":"2026-03-31T01:18:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"298419060899209575124110038011041533916","date":"2026-03-30T22:08:59+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"22808944739964844841323028160246319212","date":"2026-03-30T19:55:03+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"109824416367586575059451653155506005781","date":"2026-03-30T05:51:08+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-29T16:03:01+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-20T18:40:26+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-20T07:30:44+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-20T07:30:31+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Endocrine Disorders","date":"2026-03-17T14:33:50+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-endocrine-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bend","sideBox":"Learn more about [BMC Endocrine Disorders](http://bmcendocrdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bend/default.aspx","title":"BMC Endocrine Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ff2b7b51-5113-4fcc-8572-3998cc96f4da","owner":[],"postedDate":"April 3rd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-03T06:22:24+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-03 06:22:23","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9150077","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9150077","identity":"rs-9150077","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}