Intervention Effect of Curcumin on Sepsis-Associated Acute Kidney Injury via Regulation of p300 Expression and Protein Lactylation

Intervention Effect of Curcumin on Sepsis-Associated Acute Kidney Injury via Regulation of p300 Expression and Protein Lactylation | 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 Intervention Effect of Curcumin on Sepsis-Associated Acute Kidney Injury via Regulation of p300 Expression and Protein Lactylation Mengyuan Luo, Quanmang Zhu, Guangcai Xu, Dan Liu, Jiajun Xiao, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7041963/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 24 Sep, 2025 Read the published version in BMC Immunology → Version 1 posted 12 You are reading this latest preprint version Abstract This study investigates the protective effects and underlying mechanisms of curcumin in sepsis-associated acute kidney injury (SA-AKI). Using a cecal ligation and puncture (CLP) model to simulate SA-AKI, our results demonstrate that curcumin significantly reduced serum creatinine and urea nitrogen levels, alleviated tubular damage and inflammation, improved cellular activity, and inhibited apoptosis. Further analysis revealed that curcumin inhibited the expression of p300 and decreased protein lactylation modification in renal tissue, thereby exerting anti-inflammatory and antioxidant effects. These findings suggest that curcumin may have potential therapeutic value for the prevention and treatment of SA-AKI. Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Sepsis is a systemic inflammatory response syndrome (SIRS) caused by infection, which, when severe, can progress to sepsis-associated acute kidney injury (SA-AKI) [ 1 ] . SA-AKI is often accompanied by multiple organ dysfunction and is associated with a significant increase in mortality as well as poor long-term outcomes [ 2 – 4 ] . Therefore, early identification and effective interventions are critical for improving the prognosis of SA-AKI. However, the pathogenesis of SA-AKI is highly complex, and current treatment strategies mainly focus on supportive measures such as antimicrobial therapy, fluid resuscitation, and renal replacement therapy, lacking targeted pharmacological interventions based on its underlying mechanisms [ 5 ] . In recent years, traditional Chinese medicine (TCM) has demonstrated unique advantages in alleviating sepsis-induced organ dysfunction. Studies have shown that several active components of TCM, such as Forsythiaside A and Salidroside, can effectively mitigate sepsis-induced organ injury through multiple mechanisms, including anti-inflammatory effects, antioxidative stress, modulation of immune responses, and maintenance of cellular homeostasis [ 6 – 8 ] . Curcumin, a major bioactive compound extracted from Curcuma longa, possesses a wide range of pharmacological activities and has attracted increasing attention for its renoprotective effects in SA-AKI [ 9 ] . Curcumin has been shown to ameliorate early renal injury in sepsis by improving renal microcirculatory perfusion and suppressing pro-inflammatory cytokine release. For example, Yang et al. demonstrated that curcumin regulates m6A methylation levels by mediating the transfer of FTO via bone marrow mesenchymal stem cell-derived exosomes, thereby inhibiting the expression of oxidative stress responsive 1 (OXSR1) and attenuating renal inflammation [ 10 ] . Additionally, Huang et al. reported that curcumin can downregulate the expression of long non-coding RNA PVT1, inhibit the activation of the JNK/NF-κB signaling pathway, and reduce the production of inflammatory cytokines [ 11 ] . Lactylation, a newly identified form of post-translational modification [ 12 ] , has been increasingly recognized for its role in sepsis-associated acute kidney injury (SA-AKI). Under septic conditions, lactate levels are significantly elevated, accompanied by marked upregulation of the acetyltransferase p300, thereby creating a favorable environment for enhanced lactylation in damaged renal tubular epithelial cells. This modification may exacerbate renal dysfunction by regulating metabolic pathways, inflammatory responses, and apoptosis [ 13 – 15 ] . Previous studies have confirmed that curcumin can inhibit the activity of p300 [ 16 , 17 ] . Therefore, this study hypothesizes that curcumin may exert its renoprotective effects during the progression of SA-AKI by inhibiting p300 activity and subsequently modulating lactylation levels of relevant proteins. Materials and Methods Animal Model and Experimental Groups All animal experiments were approved by the Animal Welfare and Ethics Committee of the Laboratory Animal Center, Fudan University (Approval No: 2024-MHYY-33). Male C57BL/6 mice (8–10 weeks old, 20–25 g) were purchased from Zhongshan Hospital, Fudan University (Animal Production License No: SYXK-2016-0006). All animals were housed in a specific pathogen-free (SPF) facility under controlled conditions (temperature 22 ± 2 °C, 12 h light/dark cycle) with free access to food and water for one week of acclimatization prior to experiments. The SA-AKI model was established using the cecal ligation and puncture (CLP) method. Mice were anesthetized via intraperitoneal injection of sodium pentobarbital (100 mg/kg), and only after confirming a surgical level of anesthesia (complete loss of reflexes and unconsciousness) was a midline laparotomy performed. The distal cecum was then ligated and punctured twice with a sterile needle, and a small amount of fecal content was gently extruded before the cecum was repositioned and the abdominal cavity closed. Sham-operated mice underwent the same surgical exposure but without ligation or puncture. All procedures were conducted in strict accordance with institutional animal welfare guidelines. After model establishment, eighteen mice were randomly assigned to three groups (n = 6 per group): Sham, CLP, and CLP + Curcumin. Mice in the CLP + Curcumin group received curcumin 50 mg/kg (Selleck, USA) by oral gavage immediately after surgery. Curcumin was dissolved in corn oil (Sigma, USA). Mice in the CLP and Sham groups received an equivalent volume of corn oil by oral gavage. At 24 hours after curcumin administration, all mice were euthanized under deep anesthesia induced by intraperitoneal injection of sodium pentobarbital (100 mg/kg). Once a surgical level of anesthesia was confirmed, euthanasia was performed by cardiac puncture followed by rapid sacrifice. HK-2 Cell Culture and Treatment Human renal proximal tubular epithelial cells (HK-2, GNHu47) were obtained from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China). Cells were cultured in DMEM/F12 medium supplemented with 10% fetal bovine serum and 1% penicillin-streptomycin. All cultures were maintained in a humidified incubator at 37 °C with 5% CO₂. Cells were seeded into 6-well plates, and when cell confluence reached approximately 70%, they were randomly assigned into three groups for treatment: Control group (Con): treated with an equivalent volume of DMSO as vehicle control; LPS group (LPS): treated with 10 ng/ml lipopolysaccharide (Sigma, USA) dissolved in DMSO for 24 hours; LPS + Cur group (LPS+Cur): co-treated with 10 ng/ml LPS and 10 μM curcumin for 24 hours. After treatment, cells and medium were collected for subsequent analysis. Serum Preparation At 24 hours after CLP, mice were euthanized under anesthesia. Blood samples were collected by cardiac puncture and centrifuged at 3000 rpm for 15 minutes to separate the serum, which was stored at −20 °C until further analysis. Enzyme-Linked Immunosorbent Assay (ELISA) The levels of IL-1β (Jianglai Bio, China), TNF-α (Jianglai Bio, China), Malondialdehyde (MDA; Jiancheng Bioengineering, China) and lactate (Abcam, UK) in serum or cell culture medium were measured using ELISA kits according to the manufacturers’ instructions. Absorbance was read at 450 nm using a microplate reader (Thermo Fisher Scientific, USA). Standard curves were generated, and data were analyzed accordingly. Each experimental group included six replicate wells. Hematoxylin and Eosin (HE) Staining of Renal Tissue Kidney tissues were fixed in 4% paraformaldehyde, embedded in paraffin, and sectioned at a thickness of 4 μm. Sections were deparaffinized and rehydrated through a graded ethanol series, stained with hematoxylin for 1 minute and eosin for 30 seconds. After dehydration through graded ethanol and clearing in xylene, sections were mounted with neutral resin. Histological changes were observed and photographed under a light microscope. Immunohistochemical (IHC) Staining of Renal Tissue Kidney tissues were fixed in 4% paraformaldehyde, embedded in paraffin, and sectioned at a thickness of 4 μm. Sections were deparaffinized, subjected to antigen retrieval, and blocked with normal serum. Slides were then incubated with primary antibodies overnight at 4 °C. On the following day, sections were incubated with HRP-conjugated secondary antibodies and developed with a chromogenic substrate. Images were captured using a fluorescence microscope. CCK-8 Assay HK-2 cells were seeded in 96-well plates at a density of 1*10 6 cells per well in 100 μL of complete culture medium and incubated at 37 °C with 5% CO 2 . After treatment, Cell Counting Kit-8 (CCK-8; Baoground, China) reagent was added to each well and incubated for an additional 2 hours. The optical density (OD) was measured at 450 nm using a microplate reader to evaluate cell viability. Each experimental group included six replicate wells. TUNEL Assay HK-2 cells were seeded in multi-well plates and, after treatment, were fixed with 4% paraformaldehyde and permeabilized with 0.1% Triton X-100. The TUNEL assay was performed according to the manufacturer’s instructions (Vazyme, China). Nuclei were counterstained with DAPI, rinsed with PBS, and mounted. TUNEL-positive cells were observed and imaged under a fluorescence microscope to assess the level of apoptosis. EP300 Overexpression Plasmid Transfection For overexpression experiments, HK-2 cells were transfected with EP300 overexpression plasmid (provided by Professor Qiongzhu Dong from the Key Laboratory of Whole-Course Monitoring and Precision Intervention in Digestive Oncology) or empty vector using Lipofectamine™ 3000 Transfection Reagent (Thermo Fisher Scientific, USA) according to the manufacturer's protocol. After 6 hours of transfection, the medium was replaced with fresh complete medium, and cells were cultured for an additional 24 hours before being used for downstream assays. Western Blot Analysis Total protein was extracted from renal tissues or HK-2 cell using RIPA lysis buffer supplemented with a protease inhibitor cocktail. After protein quantification, samples were separated by SDS-PAGE and transferred onto PVDF membranes. Membranes were incubated overnight at 4 °C with Anti-pan lysine lactylation antibodies (Jingjie, China), followed by incubation with appropriate HRP-conjugated secondary antibodies. Protein bands were visualized using an enhanced chemiluminescence (ECL) system. Band intensities were quantified using ImageJ software, and relative protein expression levels were normalized to actin as the internal control. Statistical Analyses Statistical analyses were performed using SPSS version 26.0 (IBM, USA) and GraphPad Prism version 8.0 (GraphPad Software, USA). Data normality was assessed using the Shapiro-Wilk test. For normally distributed data, differences between experimental groups were analyzed using one-way analysis of variance (ANOVA). For data not following a normal distribution, the Kruskal-Wallis test was applied. Tukey’s post hoc test was used for multiple comparisons, and a p-value <0.05 was considered statistically significant. Results Curcumin Improves Renal Function and Histopathology in Septic Mice Currently, the diagnosis of AKI is primarily based on elevated serum creatinine levels, with an increase to 1.5 times the baseline considered indicative of AKI occurrence. As shown in Figure 1A and Table 1, at 24 hours post-CLP, serum creatinine (Scr) and blood urea nitrogen (Urea) levels in the CLP group were significantly higher than those in the Sham group (P < 0.001), reaching 1.5 times the baseline, indicating successful establishment of the SA-AKI model. Treatment with curcumin (CLP+Cur group) significantly reduced serum creatinine and blood urea nitrogen levels (P < 0.01). Histopathological changes in renal tubular injury were assessed by HE staining and NGAL immunofluorescence. Compared with the Sham group, the CLP group exhibited marked interstitial congestion and edema, increased inflammatory cell infiltration, partial tubular lumen obstruction, and loss of the brush border in tubular epithelial cells. In contrast, the curcumin-treated group (CLP+Cur) showed significantly alleviated tubular structural damage, reduced inflammatory infiltration, and no evident lumen obstruction or brush border loss (Figure 1B). Furthermore, NGAL-positive staining in renal tubular epithelial cells was significantly lower in the CLP+Cur group than in the CLP group (Figure 1C). These findings indicate that curcumin markedly improves renal function indices and ameliorates histopathological injury in septic mice. Curcumin Reduces Cytokine and Oxidative stress Levels, Enhances Cell Viability, and Inhibits Apoptosis in Septic Mice As shown in Figure 2A and Table 1, in vivo ELISA results indicated that the levels of inflammatory factors TNF-α and IL-1β in serum were significantly higher in the CLP group than in the Sham group (P < 0.001). However, these levels were significantly reduced in the CLP+Cur group (P < 0.01), suggesting that curcumin may exert its renoprotective effects against SA-AKI by suppressing the inflammatory response. Further analysis in vitro experiments (Figure 2B and Table 2) showed that CCK8 assays revealed a significant decrease in renal cell viability (P < 0.01) and a marked increase in MDA expression (P < 0.001) in the LPS group compared with the Con group. Following curcumin treatment, HK-2 cell viability was significantly increased (P < 0.05), while MDA levels were significantly reduced (P < 0.01), indicating that curcumin helps improve cell viability and mitigate oxidative stress-induced damage. As shown in Figure 2C, TUNEL staining demonstrated that HK-2 cell apoptosis was markedly elevated in the LPS group, whereas curcumin treatment (LPS+Cur group) significantly decreased apoptosis levels. Taken together, these findings suggest that curcumin exerts its renoprotective effects against SA-AKI by lowering renal inflammatory cytokine levels and oxidative stress, enhancing cellular viability, and inhibiting apoptosis. Curcumin Reduces Lactate Levels in vivo and vitro experiments Sepsis activates anaerobic metabolism and suppresses aerobic metabolism, leading to increased lactate production. Previous studies have shown that serum lactate levels are closely correlated with the severity of SA-AKI. As shown in Figure 3A and Table 1, in vivo experiments ELISA results indicated that serum lactate concentrations were significantly higher in the CLP group than in the Sham group (P < 0.001). Curcumin treatment (CLP+Cur group) significantly reduced serum lactate levels compared to the CLP group (P < 0.001). Similarly, in vitro experiments, as shown in Figure 3B and Table 2, lactate concentrations in the cell culture supernatant were markedly elevated in the LPS group compared to the Con group (P < 0.01). Notably, curcumin intervention (LPS + Cur group) significantly decreased lactate levels (P < 0.05). Lactate serves as a key substrate for protein lactylation; thus, elevated lactate concentrations inevitably enhance protein lactylation levels within renal tissue. Previous reports have demonstrated that protein lactylation plays a crucial role in the pathogenesis of SA-AKI. As shown in Figure 3C, the level of protein lactylation in renal tissue was significantly increased in the CLP group compared to the Sham group, whereas curcumin administration (CLP+Cur group) markedly reduced the degree of lactylation. These findings suggest that curcumin may exert its renoprotective effects against SA-AKI by attenuating lactate accumulation and the consequent lactylation modifications. Curcumin Exerts Renoprotective Effects in SA-AKI by Suppressing p300 Expression and Protein Lactylation p300 is an acetyltransferase that also facilitates protein lactylation; its upregulation promotes increased lactylation levels. It has been reported that p300 expression is significantly elevated under septic conditions. As shown in Figure 3C, Western blot analysis revealed that renal p300 expression was markedly higher in the CLP group than in the Sham group, while curcumin treatment (CLP+Cur group) significantly reduced p300 expression levels. These results indicate that the renoprotective effects of curcumin in SA-AKI may be mediated by inhibition of p300 expression. To further validate this mechanism, an HK-2 cell model was employed. Cells were transfected with an EP300 expression plasmid or an empty vector, with some cells pre-treated with curcumin. As shown in Figure 4B, Western blot results demonstrated that overexpression of p300 significantly increased cellular protein lactylation levels, and under this condition, curcumin could no longer reduce lactylation. These findings further confirm that the renoprotective effect of curcumin depends on its ability to suppress p300 expression, thereby attenuating activation of lactylation-associated pathways and exerting comprehensive anti-inflammatory and antioxidant protective effects. Discussion Sepsis is one of the leading causes of acute kidney injury (AKI), which is typically characterized by a significant increase in renal function indicators such as serum creatinine and blood urea nitrogen, as well as pathological alterations in renal tissue structure. Sepsis can also induce severe oxidative stress in the kidneys, as evidenced by elevated levels of MDA, a key end product of lipid peroxidation, and is accompanied by marked upregulation of inflammatory cytokines including IL-1β and TNF-α. In this study, we successfully established a sepsis mouse model using the CLP method and observed that curcumin exerted a significant renoprotective effect in this model. Curcumin is a natural polyphenolic compound with well-documented antioxidant and anti-inflammatory activities. The results of this study demonstrated that curcumin treatment effectively reduced elevated renal function markers, alleviated pathological damage in renal tissue, and improved oxidative stress and inflammatory responses, suggesting its potential value in the prevention and treatment of nephrotoxicity. In the lipopolysaccharide (LPS)-induced inflammation model of HK-2 cells, the JAK2/STAT3 and NF-κB signaling pathways are considered key regulators of the inflammatory response. Previous studies have confirmed that LPS stimulation significantly promotes the expression of pro-inflammatory cytokines such as IL-6 and TNF-α, whereas curcumin can inhibit the phosphorylation of key proteins within the JAK2/STAT3 and NF-κB pathways, thereby suppressing the expression of these inflammatory mediators and exerting anti-inflammatory effects [ 18 ] . Consistently, our study further showed that curcumin significantly improved the reduction in cell viability and attenuated the inflammatory response induced by LPS in HK-2 cells, providing additional evidence for its anti-inflammatory and cytoprotective effects in vitro. Recent studies have demonstrated that lactate plays a crucial role in the onset and progression of SA-AKI and is considered an important independent predictor of AKI. Lactate is a metabolic byproduct of cellular glycolysis and serves as a sensitive indicator for evaluating systemic perfusion status. During sepsis, impaired tissue perfusion leads to excessive lactate production and its release into the bloodstream, resulting in hyperlactatemia. Clinical evidence indicates that patients with hyperlactatemia generally exhibit higher APACHE II scores, an increased incidence of shock and multiple organ dysfunction syndrome (MODS), and significantly higher mortality rates. Specifically, when blood lactate levels are ≥ 4 mmol/L, the mortality rate in septic patients increases markedly [ 19 ] . Additionally, a meta-analysis by Liu et al. reported that lactic acidosis, diabetes, a mean arterial pressure (MAP) < 65 mmHg, and coagulation disorders are significant risk factors for SA-AKI [ 20 ] . At the cellular level, Tan et al. found that LPS stimulation of HK-2 cells significantly upregulated the expression of glycolysis-related genes, thereby promoting lactate production. The accumulated lactate further suppressed the expression of SIRT3 and phosphorylated AMPK (p-AMPK), resulting in reduced autophagy and increased apoptosis [ 21 ] . Collectively, these findings suggest that lactate is not only an important biomarker for the occurrence and development of SA-AKI but also actively participates in its pathogenesis at the molecular level. Further mechanistic studies have revealed that lactate can promote the lactylation modification of high mobility group box 1 (HMGB1) protein in renal tissue. As a key damage-associated molecular pattern (DAMP), HMGB1 plays a central role in the inflammatory response. Its lactylation modification has been shown to further induce the formation of neutrophil extracellular traps (NETs). NETs, which are DNA-protein complexes released by neutrophils, participate in inflammatory and thrombotic processes, and their excessive formation is considered an important factor that exacerbates renal injury in SA-AKI. Previous studies have reported a positive correlation between plasma NETs levels and the degree of HMGB1 lactylation, suggesting that lactate may contribute to SA-AKI pathogenesis by activating the HMGB1-NETs signaling axis.In addition, histone lactylation has also been implicated in the pathological process of SA-AKI [ 22 ] . Studies have shown that the lactylation level of lysine 18 on histone H3 (H3K18la) is significantly increased in SA-AKI mouse models. CUT&Tag sequencing analysis revealed that H3K18la is enriched in promoter regions within renal tissue, particularly in renal tubular epithelial cells. KEGG pathway enrichment analysis further indicated that these lactylation-associated genes are predominantly involved in pathways related to cytoskeleton remodeling, epithelial cell metabolism, and inflammatory responses. Functional studies suggest that elevated H3K18la levels can enhance the activation of the NF-κB signaling pathway, thereby aggravating inflammatory injury in renal tissue. Conversely, reducing H3K18la levels exerts anti-inflammatory effects and helps alleviate SA-AKI-induced renal dysfunction [ 23 ] . In this study, we observed that curcumin effectively downregulated the protein lactylation level in renal tissue, particularly affecting lactylation modifications of histones and inflammation-related proteins, thereby exerting renoprotective effects. These findings suggest that curcumin may mitigate the pathological progression of SA-AKI by interfering with lactylation-related pathways, including inhibition of the HMGB1-NETs axis and H3K18la-mediated NF-κB activation. As a key acetyltransferase, p300 not only participates in histone acetylation but also plays a crucial role in protein lactylation. Previous studies have demonstrated that p300, through its catalytic activity, can promote the lactylation modification of various substrate proteins, including histones and inflammation-related signaling molecules, thereby regulating cellular processes such as inflammatory responses, apoptosis, and oxidative stress. Elevated expression of p300 has been consistently observed in sepsis and associated organ injuries, suggesting its central role in the pathogenesis of SA-AKI. Consistent with these findings, our study showed that curcumin significantly downregulated p300 expression, thereby markedly suppressing protein lactylation levels in renal tissue, which in turn alleviated oxidative stress and inflammatory responses in the kidney. This not only highlights the pivotal role of p300 in the pathophysiology of SA-AKI but also suggests that p300 may serve as an important regulator of lactylation levels and their pathological consequences. Future investigations could focus on the therapeutic potential of selective p300 inhibitors or p300 gene silencing strategies in SA-AKI, as well as elucidating the specific substrate spectrum and functional roles of p300-mediated lactylation. Such research would expand our understanding of lactylation and p300-related signaling pathways, providing a more targeted approach for the treatment of SA-AKI and other inflammation-related diseases. This study also has certain limitations: the specific lactylated substrate proteins affected by curcumin and their associated functional pathways have not yet been fully identified. Future studies are warranted to further investigate the regulatory effects of curcumin on the spectrum of lactylated target proteins and to elucidate their precise roles in the pathogenesis of SA-AKI, thereby laying a more robust foundation for its potential clinical translation. Conclusion In summary, our findings indicate that curcumin exerts significant renoprotective effects by inhibiting protein lactylation modifications in renal tissue, demonstrating its potential to alleviate sepsis-associated acute kidney injury. This provides novel insights and potential therapeutic targets for the intervention and treatment of SA-AKI. Abbreviations SA-AKI Sepsis-associated Acute Kidney Injury CLP Cecal Ligation and Puncture HK-2 Human proximal tubular epithelial cells MDA Malondialdehyde Declarations Ethics approval and consent to participate ： All animal experiments were approved by the Animal Welfare and Ethics Committee of the Laboratory Animal Center, Fudan University (Approval No: 2024-MHYY-33). Clinical trial number not applicable. Consent for publication ： Not applicable. Availability of data and material ： Data and material are available on request. Competing interests ： The authors declare no competing interests. Funding ： This study was supported by the Anhui Provincial Traditional Chinese Medicine Inheritance and Innovation Research Project (Grant No: 2024CCCX086) & The Key Research and Development Program of Anhui Province (Grant No. 2022e07020064). Authors’ contributions ： Mengyuan Luo and Quanmang Zhu contributed equally to this work. Mengyuan Luo conducted the animal experiments, established the sepsis model, and participated in manuscript writing. Quanmang Zhu performed the cell culture experiments, Western blot analysis, and statistical evaluation. Dan Liu carried out the ELISA, immunohistochemistry, and immunofluorescence assays. Guangcai Xu assisted in data collection and figure preparation. Qiqing Shi supervised the study, revised the manuscript, and Fund support. Jiajun Xiao contributed to experimental design, interpretation of results and partial Fund support. All authors reviewed and approved the final manuscript. Acknowledgements ： We sincerely thank Professor Qiongzhu Dong from the Key Laboratory of Whole-Course Monitoring and Precision Intervention in Digestive Oncology, Shanghai Municipal Health Commission, for generously providing the EP300 expression plasmid and for her valuable support throughout the study. 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Supplementary Files fulllengthWesternblotsofFigure3Cand4.pdf Supplementary Figure: full-length Western blots of Figure 3C and 4 Cite Share Download PDF Status: Published Journal Publication published 24 Sep, 2025 Read the published version in BMC Immunology → Version 1 posted Editorial decision: Revision requested 28 Jul, 2025 Reviewers agreed at journal 26 Jul, 2025 Reviews received at journal 25 Jul, 2025 Reviewers agreed at journal 24 Jul, 2025 Reviewers agreed at journal 24 Jul, 2025 Reviews received at journal 21 Jul, 2025 Reviewers agreed at journal 16 Jul, 2025 Reviewers invited by journal 13 Jul, 2025 Editor assigned by journal 12 Jul, 2025 Editor invited by journal 11 Jul, 2025 Submission checks completed at journal 11 Jul, 2025 First submitted to journal 11 Jul, 2025 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. 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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-7041963","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":486171391,"identity":"bc3f41a8-b78e-4e03-a733-d8698a540f0e","order_by":0,"name":"Mengyuan Luo","email":"","orcid":"","institution":"Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Mengyuan","middleName":"","lastName":"Luo","suffix":""},{"id":486171392,"identity":"5f883f19-889b-4308-ba5f-bf83a44f2980","order_by":1,"name":"Quanmang Zhu","email":"","orcid":"","institution":"Bengbu Hospital of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Quanmang","middleName":"","lastName":"Zhu","suffix":""},{"id":486171393,"identity":"82d867f4-52e9-4571-9d49-41047666d1b9","order_by":2,"name":"Guangcai Xu","email":"","orcid":"","institution":"Bengbu Hospital of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Guangcai","middleName":"","lastName":"Xu","suffix":""},{"id":486171394,"identity":"d341028f-d4f0-45fc-94f8-e1d5452beb1f","order_by":3,"name":"Dan Liu","email":"","orcid":"","institution":"Bengbu Hospital of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Dan","middleName":"","lastName":"Liu","suffix":""},{"id":486171395,"identity":"249f4092-c6a5-4089-bf73-83d2d07b67f8","order_by":4,"name":"Jiajun Xiao","email":"","orcid":"","institution":"Bengbu Hospital of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Jiajun","middleName":"","lastName":"Xiao","suffix":""},{"id":486171397,"identity":"78b1f60d-2932-4a4b-90dc-51a0d51def04","order_by":5,"name":"Qiqing Shi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1klEQVRIiWNgGAWjYDACCcYGBoYKCR5+9sbGBx+I13LGRkay53Cz4QzitAAxY1uajcGM9DZpDmJ0yM9ubrzxhu0wj4HkwwZpBgY7Od0GAloM7hxstpzDc5jHXDqxwbiAIdnY7AAhLRKJbdI8Eod5LGcnNiTPYDiQuI2QFvkZIC0GQIfdPNhwmIcYLQw3QFoS0ngMbjA2NhOlxeBGItAvB2x4JHsSmxlnGBDhF/kZ6Q9vvP0nYc/Pfvz5jw8VdnIEtYCABA/CUiKUo2kZBaNgFIyCUYAFAAC5jEQ9VKICHwAAAABJRU5ErkJggg==","orcid":"","institution":"Bengbu Hospital of Traditional Chinese Medicine","correspondingAuthor":true,"prefix":"","firstName":"Qiqing","middleName":"","lastName":"Shi","suffix":""}],"badges":[],"createdAt":"2025-07-04 01:23:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7041963/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7041963/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12865-025-00750-3","type":"published","date":"2025-09-24T15:57:27+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":87005733,"identity":"e137c7d3-3437-4f00-80c5-dc2d8650b15f","added_by":"auto","created_at":"2025-07-18 08:15:56","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1091618,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Compared with the Sham group, serum creatinine and blood urea nitrogen levels were significantly elevated in the CLP group (P \u0026lt; 0.001). These levels were significantly reduced in the CLP + Cur group compared to the CLP group (P \u0026lt; 0.001).\u003cbr\u003e\n(B) Representative light microscopy images of HE-stained renal tissue. The CLP group exhibited tubular dilation, brush border loss, and flattening and desquamation of tubular epithelial cells compared to the Sham group. The CLP + Cur group showed markedly reduced renal injury compared to the CLP group.\u003cbr\u003e\n(C) Immunofluorescence images showing NGAL staining. NGAL expression was markedly increased in the CLP group and significantly decreased in the CLP + Cur group.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7041963/v1/4eed90fa34bb0f27d486b932.png"},{"id":87005732,"identity":"b9501dd6-b08b-4393-8ea9-ab4d71b8816b","added_by":"auto","created_at":"2025-07-18 08:15:55","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":151401,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Expression levels of TNF-α and IL-1β were significantly increased in the CLP group compared to the Sham group (P \u0026lt; 0.001), while curcumin treatment (CLP + Cur group) significantly reduced their expression compared to the CLP group (P \u0026lt; 0.001).\u003c/p\u003e\n\u003cp\u003e(B) MDA level was significantly increased in the LPS group compared to the Con group (P \u0026lt; 0.001) and significantly decreased in the LPS + Cur group compared to the LPS group (P \u0026lt; 0.01).\u003cbr\u003e\n(C) Cell viability was significantly decreased in the LPS group compared to the Con group (P \u0026lt; 0.001) and significantly increased in the LPS + Cur group compared to the LPS group (P \u0026lt; 0.001).\u003cbr\u003e\n(D) Immunofluorescence images of TUNEL staining. TUNEL-positive signals were markedly increased in the LPS group and significantly decreased in the LPS + Cur group.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7041963/v1/6ef6d59ab1f633ca6dc46d9b.png"},{"id":87005731,"identity":"547800af-c6bc-4248-afb6-6fe8c48856e1","added_by":"auto","created_at":"2025-07-18 08:15:55","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":129939,"visible":true,"origin":"","legend":"\u003cp\u003e(A) In vivo, serum lactate levels were significantly increased in the CLP group compared to the Sham group (P \u0026lt; 0.001). These levels were significantly decreased in the CLP + Cur group compared to the CLP group (P \u0026lt; 0.001).\u003c/p\u003e\n\u003cp\u003e(B) In vitro, cell culture medium lactate levels were significantly increased in the LPS group compared to the Con group (P \u0026lt; 0.01). These levels were significantly decreased in the LPS + Cur group compared to the LPS group (P \u0026lt; 0.05).\u003cbr\u003e\n(C) Total protein lactylation levels in renal tissues were markedly elevated in the CLP group compared to the Sham group and were significantly reduced in the CLP + Cur group compared to the CLP group.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7041963/v1/ae95581c7590221082d0c08e.png"},{"id":87006598,"identity":"24fd06a9-a163-44e1-b3a3-825b3b4de887","added_by":"auto","created_at":"2025-07-18 08:23:56","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":120846,"visible":true,"origin":"","legend":"\u003cp\u003eCompared with HK-2 cells transfected with an empty vector, those transfected with an EP300 overexpression plasmid exhibited a significant increase in total protein lactylation levels, which were notably reduced following additional treatment with curcumin.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7041963/v1/c61e134aa12125079f32f801.png"},{"id":92430455,"identity":"6e76bbbb-1fa9-4b44-909d-175fea91bb66","added_by":"auto","created_at":"2025-09-29 16:04:53","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2104856,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7041963/v1/454fb5ae-1e12-4fe2-a87f-8d6100fd7a91.pdf"},{"id":87005735,"identity":"8e6f170c-7499-4e35-ab85-1a93318d6d0c","added_by":"auto","created_at":"2025-07-18 08:15:56","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":203325,"visible":true,"origin":"","legend":"\u003cp\u003eSupplementary Figure: full-length Western blots of Figure 3C and 4\u003c/p\u003e","description":"","filename":"fulllengthWesternblotsofFigure3Cand4.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7041963/v1/f2419e01e6cad6cc5159e04e.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Intervention Effect of Curcumin on Sepsis-Associated Acute Kidney Injury via Regulation of p300 Expression and Protein Lactylation","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSepsis is a systemic inflammatory response syndrome (SIRS) caused by infection, which, when severe, can progress to sepsis-associated acute kidney injury (SA-AKI)\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. SA-AKI is often accompanied by multiple organ dysfunction and is associated with a significant increase in mortality as well as poor long-term outcomes\u003csup\u003e[\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. Therefore, early identification and effective interventions are critical for improving the prognosis of SA-AKI. However, the pathogenesis of SA-AKI is highly complex, and current treatment strategies mainly focus on supportive measures such as antimicrobial therapy, fluid resuscitation, and renal replacement therapy, lacking targeted pharmacological interventions based on its underlying mechanisms\u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eIn recent years, traditional Chinese medicine (TCM) has demonstrated unique advantages in alleviating sepsis-induced organ dysfunction. Studies have shown that several active components of TCM, such as Forsythiaside A and Salidroside, can effectively mitigate sepsis-induced organ injury through multiple mechanisms, including anti-inflammatory effects, antioxidative stress, modulation of immune responses, and maintenance of cellular homeostasis\u003csup\u003e[\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e. Curcumin, a major bioactive compound extracted from Curcuma longa, possesses a wide range of pharmacological activities and has attracted increasing attention for its renoprotective effects in SA-AKI\u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e. Curcumin has been shown to ameliorate early renal injury in sepsis by improving renal microcirculatory perfusion and suppressing pro-inflammatory cytokine release. For example, Yang et al. demonstrated that curcumin regulates m6A methylation levels by mediating the transfer of FTO via bone marrow mesenchymal stem cell-derived exosomes, thereby inhibiting the expression of oxidative stress responsive 1 (OXSR1) and attenuating renal inflammation\u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e. Additionally, Huang et al. reported that curcumin can downregulate the expression of long non-coding RNA PVT1, inhibit the activation of the JNK/NF-κB signaling pathway, and reduce the production of inflammatory cytokines\u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eLactylation, a newly identified form of post-translational modification\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e, has been increasingly recognized for its role in sepsis-associated acute kidney injury (SA-AKI). Under septic conditions, lactate levels are significantly elevated, accompanied by marked upregulation of the acetyltransferase p300, thereby creating a favorable environment for enhanced lactylation in damaged renal tubular epithelial cells. This modification may exacerbate renal dysfunction by regulating metabolic pathways, inflammatory responses, and apoptosis\u003csup\u003e[\u003cspan additionalcitationids=\"CR14\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e. Previous studies have confirmed that curcumin can inhibit the activity of p300\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e. Therefore, this study hypothesizes that curcumin may exert its renoprotective effects during the progression of SA-AKI by inhibiting p300 activity and subsequently modulating lactylation levels of relevant proteins.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003eAnimal Model and Experimental Groups\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll animal experiments were approved by the Animal Welfare and Ethics Committee of the Laboratory Animal Center, Fudan University (Approval No: 2024-MHYY-33). \u0026nbsp;Male C57BL/6 mice (8\u0026ndash;10 weeks old, 20\u0026ndash;25 g) were purchased from Zhongshan Hospital, Fudan University (Animal Production License No: SYXK-2016-0006). All animals were housed in a specific pathogen-free (SPF) facility under controlled conditions (temperature 22 \u0026plusmn; 2 \u0026deg;C, 12 h light/dark cycle) with free access to food and water for one week of acclimatization prior to experiments.\u003c/p\u003e\n\u003cp\u003eThe SA-AKI model was established using the cecal ligation and puncture (CLP) method. Mice were anesthetized via intraperitoneal injection of sodium pentobarbital (100 mg/kg), and only after confirming a surgical level of anesthesia (complete loss of reflexes and unconsciousness) was a midline laparotomy performed. The distal cecum was then ligated and punctured twice with a sterile needle, and a small amount of fecal content was gently extruded before the cecum was repositioned and the abdominal cavity closed. Sham-operated mice underwent the same surgical exposure but without ligation or puncture. All procedures were conducted in strict accordance with institutional animal welfare guidelines.\u003c/p\u003e\n\u003cp\u003eAfter model establishment, eighteen mice were randomly assigned to three groups (n = 6 per group): Sham, CLP, and CLP + Curcumin. Mice in the CLP + Curcumin group received curcumin 50 mg/kg (Selleck, USA) by oral gavage immediately after surgery. Curcumin was dissolved in corn oil (Sigma, USA). Mice in the CLP and Sham groups received an equivalent volume of corn oil by oral gavage.\u003c/p\u003e\n\u003cp\u003eAt 24 hours after curcumin administration, all mice were euthanized under deep anesthesia induced by intraperitoneal injection of sodium pentobarbital (100 mg/kg). Once a surgical level of anesthesia was confirmed, euthanasia was performed by cardiac puncture followed by rapid sacrifice.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHK-2 Cell Culture and Treatment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHuman renal proximal tubular epithelial cells (HK-2, GNHu47) were obtained from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China). Cells were cultured in DMEM/F12 medium supplemented with 10% fetal bovine serum and 1% penicillin-streptomycin. All cultures were maintained in a humidified incubator at 37 \u0026deg;C with 5% CO₂. Cells were seeded into 6-well plates, and when cell confluence reached approximately 70%, they were randomly assigned into three groups for treatment: Control group (Con): treated with an equivalent volume of DMSO as vehicle control; LPS group (LPS): treated with 10 ng/ml lipopolysaccharide (Sigma, USA) dissolved in DMSO for 24 hours; LPS + Cur group (LPS+Cur): co-treated with 10 ng/ml LPS and 10 \u0026mu;M curcumin for 24 hours. After treatment, cells and medium were collected for subsequent analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSerum Preparation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAt 24 hours after CLP, mice were euthanized under anesthesia. Blood samples were collected by cardiac puncture and centrifuged at 3000 rpm for 15 minutes to separate the serum, which was stored at \u0026minus;20 \u0026deg;C until further analysis. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEnzyme-Linked Immunosorbent Assay (ELISA)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe levels of IL-1\u0026beta; (Jianglai Bio, China), TNF-\u0026alpha; (Jianglai Bio, China), Malondialdehyde (MDA; Jiancheng Bioengineering, China) and lactate (Abcam, UK) in serum or cell culture medium were measured using ELISA kits according to the manufacturers\u0026rsquo; instructions. Absorbance was read at 450 nm using a microplate reader (Thermo Fisher Scientific, USA). Standard curves were generated, and data were analyzed accordingly. Each experimental group included six replicate wells.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHematoxylin and Eosin (HE) Staining of Renal Tissue\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eKidney tissues were fixed in 4% paraformaldehyde, embedded in paraffin, and sectioned at a thickness of 4 \u0026mu;m. Sections were deparaffinized and rehydrated through a graded ethanol series, stained with hematoxylin for 1 minute and eosin for 30 seconds. After dehydration through graded ethanol and clearing in xylene, sections were mounted with neutral resin. Histological changes were observed and photographed under a light microscope.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eImmunohistochemical (IHC) Staining of Renal Tissue\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eKidney tissues were fixed in 4% paraformaldehyde, embedded in paraffin, and sectioned at a thickness of 4 \u0026mu;m. Sections were deparaffinized, subjected to antigen retrieval, and blocked with normal serum. Slides were then incubated with primary antibodies overnight at 4 \u0026deg;C. On the following day, sections were incubated with HRP-conjugated secondary antibodies and developed with a chromogenic substrate. Images were captured using a fluorescence microscope.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCCK-8 Assay\u003cbr\u003e\u003c/strong\u003eHK-2 cells were seeded in 96-well plates at a density of 1*10\u003csup\u003e6\u003c/sup\u003e cells per well in 100 \u0026mu;L of complete culture medium and incubated at 37 \u0026deg;C with 5% CO\u003csub\u003e2\u003c/sub\u003e. After treatment, \u0026nbsp;Cell Counting Kit-8 (CCK-8; Baoground, China) reagent was added to each well and incubated for an additional 2 hours. The optical density (OD) was measured at 450 nm using a microplate reader to evaluate cell viability. Each experimental group included six replicate wells.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTUNEL Assay\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHK-2 cells were seeded in multi-well plates and, after treatment, were fixed with 4% paraformaldehyde and permeabilized with 0.1% Triton X-100. The TUNEL assay was performed according to the manufacturer\u0026rsquo;s instructions (Vazyme, China). Nuclei were counterstained with DAPI, rinsed with PBS, and mounted. TUNEL-positive cells were observed and imaged under a fluorescence microscope to assess the level of apoptosis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEP300 Overexpression Plasmid Transfection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor overexpression experiments, HK-2 cells were transfected with EP300 overexpression plasmid (provided by Professor Qiongzhu Dong from the Key Laboratory of Whole-Course Monitoring and Precision Intervention in Digestive Oncology) or empty vector using Lipofectamine\u0026trade; 3000 Transfection Reagent (Thermo Fisher Scientific, USA) according to the manufacturer\u0026apos;s protocol. After 6 hours of transfection, the medium was replaced with fresh complete medium, and cells were cultured for an additional 24 hours before being used for downstream assays.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eWestern Blot Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTotal protein was extracted from renal tissues or HK-2 cell using RIPA lysis buffer supplemented with a protease inhibitor cocktail. After protein quantification, samples were separated by SDS-PAGE and transferred onto PVDF membranes. Membranes were incubated overnight at 4 \u0026deg;C with Anti-pan lysine lactylation antibodies (Jingjie, China), followed by incubation with appropriate HRP-conjugated secondary antibodies. Protein bands were visualized using an enhanced chemiluminescence (ECL) system. Band intensities were quantified using ImageJ software, and relative protein expression levels were normalized to actin as the internal control.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Analyses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStatistical analyses were performed using SPSS version 26.0 (IBM, USA) and GraphPad Prism version 8.0 (GraphPad Software, USA). Data normality was assessed using the Shapiro-Wilk test. For normally distributed data, differences between experimental groups were analyzed using one-way analysis of variance (ANOVA). For data not following a normal distribution, the Kruskal-Wallis test was applied. Tukey\u0026rsquo;s post hoc test was used for multiple comparisons, and a p-value \u0026lt;0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eCurcumin Improves Renal Function and Histopathology in Septic Mice\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCurrently, the diagnosis of AKI is primarily based on elevated serum creatinine levels, with an increase to 1.5 times the baseline considered indicative of AKI occurrence. As shown in Figure 1A and Table 1, at 24 hours post-CLP, serum creatinine (Scr) and blood urea nitrogen (Urea) levels in the CLP group were significantly higher than those in the Sham group (P \u0026lt; 0.001), reaching 1.5 times the baseline, indicating successful establishment of the SA-AKI model. Treatment with curcumin (CLP+Cur group) significantly reduced serum creatinine and blood urea nitrogen levels (P \u0026lt; 0.01).\u003c/p\u003e\n\u003cp\u003eHistopathological changes in renal tubular injury were assessed by HE staining and NGAL immunofluorescence. Compared with the Sham group, the CLP group exhibited marked interstitial congestion and edema, increased inflammatory cell infiltration, partial tubular lumen obstruction, and loss of the brush border in tubular epithelial cells. In contrast, the curcumin-treated group (CLP+Cur) showed significantly alleviated tubular structural damage, reduced inflammatory infiltration, and no evident lumen obstruction or brush border loss (Figure 1B). Furthermore, NGAL-positive staining in renal tubular epithelial cells was significantly lower in the CLP+Cur group than in the CLP group (Figure 1C). These findings indicate that curcumin markedly improves renal function indices and ameliorates histopathological injury in septic mice.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCurcumin Reduces Cytokine and Oxidative stress Levels, Enhances Cell Viability, and Inhibits Apoptosis in Septic Mice\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAs shown in Figure 2A and Table 1, in vivo\u0026nbsp;ELISA results indicated that the levels of inflammatory factors TNF-\u0026alpha; and IL-1\u0026beta; in serum were significantly higher in the CLP group than in the Sham group (P \u0026lt; 0.001). However, these levels were significantly reduced in the CLP+Cur group (P \u0026lt; 0.01), suggesting that curcumin may exert its renoprotective effects against SA-AKI by suppressing the inflammatory response.\u003c/p\u003e\n\u003cp\u003eFurther analysis in vitro experiments (Figure 2B and Table 2) showed that CCK8 assays revealed a significant decrease in renal cell viability (P \u0026lt; 0.01) and a marked increase in MDA expression (P \u0026lt; 0.001) in the LPS group compared with the Con group. Following curcumin treatment, HK-2 cell viability was significantly increased (P \u0026lt; 0.05), while MDA levels were significantly reduced (P \u0026lt; 0.01), indicating that curcumin helps improve cell viability and mitigate oxidative stress-induced damage.\u003c/p\u003e\n\u003cp\u003eAs shown in Figure 2C, TUNEL staining demonstrated that HK-2 cell apoptosis was markedly elevated in the LPS group, whereas curcumin treatment (LPS+Cur group) significantly decreased apoptosis levels. Taken together, these findings suggest that curcumin exerts its renoprotective effects against SA-AKI by lowering renal inflammatory cytokine levels and oxidative stress, enhancing cellular viability, and inhibiting apoptosis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCurcumin Reduces Lactate Levels in vivo and vitro experiments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSepsis activates anaerobic metabolism and suppresses aerobic metabolism, leading to increased lactate production. Previous studies have shown that serum lactate levels are closely correlated with the severity of SA-AKI. As shown in Figure 3A and Table 1, in vivo experiments\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eELISA results indicated that serum lactate concentrations were significantly higher in the CLP group than in the Sham group (P \u0026lt; 0.001). Curcumin treatment (CLP+Cur group) significantly reduced serum lactate levels compared to the CLP group (P \u0026lt; 0.001). Similarly, in vitro experiments, as shown in Figure 3B and Table 2, lactate concentrations in the cell culture supernatant were markedly elevated in the LPS group compared to the Con group (P \u0026lt; 0.01). Notably, curcumin intervention (LPS + Cur group) significantly decreased lactate levels (P \u0026lt; 0.05).\u003c/p\u003e\n\u003cp\u003eLactate serves as a key substrate for protein lactylation; thus, elevated lactate concentrations inevitably enhance protein lactylation levels within renal tissue. Previous reports have demonstrated that protein lactylation plays a crucial role in the pathogenesis of SA-AKI. As shown in Figure 3C, the level of protein lactylation in renal tissue was significantly increased in the CLP group compared to the Sham group, whereas curcumin administration (CLP+Cur group) markedly reduced the degree of lactylation. These findings suggest that curcumin may exert its renoprotective effects against SA-AKI by attenuating lactate accumulation and the consequent lactylation modifications.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCurcumin Exerts Renoprotective Effects in SA-AKI by Suppressing p300 Expression and Protein Lactylation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ep300 is an acetyltransferase that also facilitates protein lactylation; its upregulation promotes increased lactylation levels. It has been reported that p300 expression is significantly elevated under septic conditions. As shown in Figure 3C, Western blot analysis revealed that renal p300 expression was markedly higher in the CLP group than in the Sham group, while curcumin treatment (CLP+Cur group) significantly reduced p300 expression levels. These results indicate that the renoprotective effects of curcumin in SA-AKI may be mediated by inhibition of p300 expression.\u003c/p\u003e\n\u003cp\u003eTo further validate this mechanism, an HK-2 cell model was employed. Cells were transfected with an EP300 expression plasmid or an empty vector, with some cells pre-treated with curcumin. As shown in Figure 4B, Western blot results demonstrated that overexpression of p300 significantly increased cellular protein lactylation levels, and under this condition, curcumin could no longer reduce lactylation. These findings further confirm that the renoprotective effect of curcumin depends on its ability to suppress p300 expression, thereby attenuating activation of lactylation-associated pathways and exerting comprehensive anti-inflammatory and antioxidant protective effects.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSepsis is one of the leading causes of acute kidney injury (AKI), which is typically characterized by a significant increase in renal function indicators such as serum creatinine and blood urea nitrogen, as well as pathological alterations in renal tissue structure. Sepsis can also induce severe oxidative stress in the kidneys, as evidenced by elevated levels of MDA, a key end product of lipid peroxidation, and is accompanied by marked upregulation of inflammatory cytokines including IL-1β and TNF-α. In this study, we successfully established a sepsis mouse model using the CLP method and observed that curcumin exerted a significant renoprotective effect in this model.\u003c/p\u003e\u003cp\u003eCurcumin is a natural polyphenolic compound with well-documented antioxidant and anti-inflammatory activities. The results of this study demonstrated that curcumin treatment effectively reduced elevated renal function markers, alleviated pathological damage in renal tissue, and improved oxidative stress and inflammatory responses, suggesting its potential value in the prevention and treatment of nephrotoxicity. In the lipopolysaccharide (LPS)-induced inflammation model of HK-2 cells, the JAK2/STAT3 and NF-κB signaling pathways are considered key regulators of the inflammatory response. Previous studies have confirmed that LPS stimulation significantly promotes the expression of pro-inflammatory cytokines such as IL-6 and TNF-α, whereas curcumin can inhibit the phosphorylation of key proteins within the JAK2/STAT3 and NF-κB pathways, thereby suppressing the expression of these inflammatory mediators and exerting anti-inflammatory effects\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e. Consistently, our study further showed that curcumin significantly improved the reduction in cell viability and attenuated the inflammatory response induced by LPS in HK-2 cells, providing additional evidence for its anti-inflammatory and cytoprotective effects in vitro.\u003c/p\u003e\u003cp\u003eRecent studies have demonstrated that lactate plays a crucial role in the onset and progression of SA-AKI and is considered an important independent predictor of AKI. Lactate is a metabolic byproduct of cellular glycolysis and serves as a sensitive indicator for evaluating systemic perfusion status. During sepsis, impaired tissue perfusion leads to excessive lactate production and its release into the bloodstream, resulting in hyperlactatemia. Clinical evidence indicates that patients with hyperlactatemia generally exhibit higher APACHE II scores, an increased incidence of shock and multiple organ dysfunction syndrome (MODS), and significantly higher mortality rates. Specifically, when blood lactate levels are \u0026ge;\u0026thinsp;4 mmol/L, the mortality rate in septic patients increases markedly\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/sup\u003e. Additionally, a meta-analysis by Liu et al. reported that lactic acidosis, diabetes, a mean arterial pressure (MAP)\u0026thinsp;\u0026lt;\u0026thinsp;65 mmHg, and coagulation disorders are significant risk factors for SA-AKI\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e. At the cellular level, Tan et al. found that LPS stimulation of HK-2 cells significantly upregulated the expression of glycolysis-related genes, thereby promoting lactate production. The accumulated lactate further suppressed the expression of SIRT3 and phosphorylated AMPK (p-AMPK), resulting in reduced autophagy and increased apoptosis\u003csup\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e. Collectively, these findings suggest that lactate is not only an important biomarker for the occurrence and development of SA-AKI but also actively participates in its pathogenesis at the molecular level.\u003c/p\u003e\u003cp\u003eFurther mechanistic studies have revealed that lactate can promote the lactylation modification of high mobility group box 1 (HMGB1) protein in renal tissue. As a key damage-associated molecular pattern (DAMP), HMGB1 plays a central role in the inflammatory response. Its lactylation modification has been shown to further induce the formation of neutrophil extracellular traps (NETs). NETs, which are DNA-protein complexes released by neutrophils, participate in inflammatory and thrombotic processes, and their excessive formation is considered an important factor that exacerbates renal injury in SA-AKI. Previous studies have reported a positive correlation between plasma NETs levels and the degree of HMGB1 lactylation, suggesting that lactate may contribute to SA-AKI pathogenesis by activating the HMGB1-NETs signaling axis.In addition, histone lactylation has also been implicated in the pathological process of SA-AKI\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. Studies have shown that the lactylation level of lysine 18 on histone H3 (H3K18la) is significantly increased in SA-AKI mouse models. CUT\u0026amp;Tag sequencing analysis revealed that H3K18la is enriched in promoter regions within renal tissue, particularly in renal tubular epithelial cells. KEGG pathway enrichment analysis further indicated that these lactylation-associated genes are predominantly involved in pathways related to cytoskeleton remodeling, epithelial cell metabolism, and inflammatory responses. Functional studies suggest that elevated H3K18la levels can enhance the activation of the NF-κB signaling pathway, thereby aggravating inflammatory injury in renal tissue. Conversely, reducing H3K18la levels exerts anti-inflammatory effects and helps alleviate SA-AKI-induced renal dysfunction\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e. In this study, we observed that curcumin effectively downregulated the protein lactylation level in renal tissue, particularly affecting lactylation modifications of histones and inflammation-related proteins, thereby exerting renoprotective effects. These findings suggest that curcumin may mitigate the pathological progression of SA-AKI by interfering with lactylation-related pathways, including inhibition of the HMGB1-NETs axis and H3K18la-mediated NF-κB activation.\u003c/p\u003e\u003cp\u003eAs a key acetyltransferase, p300 not only participates in histone acetylation but also plays a crucial role in protein lactylation. Previous studies have demonstrated that p300, through its catalytic activity, can promote the lactylation modification of various substrate proteins, including histones and inflammation-related signaling molecules, thereby regulating cellular processes such as inflammatory responses, apoptosis, and oxidative stress. Elevated expression of p300 has been consistently observed in sepsis and associated organ injuries, suggesting its central role in the pathogenesis of SA-AKI. Consistent with these findings, our study showed that curcumin significantly downregulated p300 expression, thereby markedly suppressing protein lactylation levels in renal tissue, which in turn alleviated oxidative stress and inflammatory responses in the kidney. This not only highlights the pivotal role of p300 in the pathophysiology of SA-AKI but also suggests that p300 may serve as an important regulator of lactylation levels and their pathological consequences. Future investigations could focus on the therapeutic potential of selective p300 inhibitors or p300 gene silencing strategies in SA-AKI, as well as elucidating the specific substrate spectrum and functional roles of p300-mediated lactylation. Such research would expand our understanding of lactylation and p300-related signaling pathways, providing a more targeted approach for the treatment of SA-AKI and other inflammation-related diseases.\u003c/p\u003e\u003cp\u003eThis study also has certain limitations: the specific lactylated substrate proteins affected by curcumin and their associated functional pathways have not yet been fully identified. Future studies are warranted to further investigate the regulatory effects of curcumin on the spectrum of lactylated target proteins and to elucidate their precise roles in the pathogenesis of SA-AKI, thereby laying a more robust foundation for its potential clinical translation.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, our findings indicate that curcumin exerts significant renoprotective effects by inhibiting protein lactylation modifications in renal tissue, demonstrating its potential to alleviate sepsis-associated acute kidney injury. This provides novel insights and potential therapeutic targets for the intervention and treatment of SA-AKI.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eSA-AKI \u0026nbsp;Sepsis-associated Acute Kidney Injury\u003c/p\u003e\n\u003cp\u003eCLP \u0026nbsp;Cecal Ligation and Puncture\u003c/p\u003e\n\u003cp\u003eHK-2 \u0026nbsp;Human proximal tubular epithelial cells\u003c/p\u003e\n\u003cp\u003eMDA \u0026nbsp; Malondialdehyde\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll animal experiments were approved by the Animal Welfare and Ethics Committee of the Laboratory Animal Center, Fudan University (Approval No: 2024-MHYY-33).\u003c/p\u003e\n\u003cp\u003eClinical trial number not applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData and material are available on request.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by the Anhui Provincial Traditional Chinese Medicine Inheritance and Innovation Research Project (Grant No: 2024CCCX086) \u0026amp; The Key Research and Development Program of Anhui Province (Grant No. 2022e07020064).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMengyuan Luo and Quanmang Zhu contributed equally to this work. Mengyuan Luo conducted the animal experiments, established the sepsis model, and participated in manuscript writing. Quanmang Zhu performed the cell culture experiments, Western blot analysis, and statistical evaluation. Dan Liu carried out the ELISA, immunohistochemistry, and immunofluorescence assays. Guangcai Xu assisted in data collection and figure preparation. Qiqing Shi supervised the study, revised the manuscript, and Fund support. Jiajun Xiao contributed to experimental design, interpretation of results and partial Fund support. All authors reviewed and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe sincerely thank Professor Qiongzhu Dong from the Key Laboratory of Whole-Course Monitoring and Precision Intervention in Digestive Oncology, Shanghai Municipal Health Commission, for generously providing the EP300 expression plasmid and for her valuable support throughout the study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eWu VC, Chueh SJ, Chang JT, et al. Acute Kidney Injury and Septic Shock- Defined by Updated Sepsis-3 Criteria in Critically Ill Patients. \u003cem\u003eJ Clin Med\u003c/em\u003e. 2019;8(10):1731.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003ePais T, Jorge S, Lopes JA. Acute Kidney Injury in Sepsis. Int J Mol Sci. 2024;25(11):5924.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eWhite KC, Serpa-Neto A, Hurford R, et al. Sepsis-associated acute kidney injury in the intensive care unit: incidence, patient characteristics, timing, trajectory, treatment, and associated outcomes. A multicenter, observational study.\u0026nbsp;Intensive Care Med. 2023;49(9):1079-1089.\u003c/li\u003e\n \u003cli\u003eZarbock A, Nadim MK, Pickkers P, et al. Sepsis-associated acute kidney injury: consensus report of the 28th Acute Disease Quality Initiative workgroup.\u0026nbsp;Nat Rev Nephrol. 2023;19(6):401-417.\u003c/li\u003e\n \u003cli\u003eZarbock A, Koyner JL, Gomez H, et al. Acute Disease Quality Initiative group. Sepsis-associated acute kidney injury-treatment standard. Nephrol Dial Transplant. 2023;39(1):26-35.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eChen Y, Wei W, Fu J, et al. Forsythiaside A ameliorates sepsis-induced acute kidney injury via anti-inflammation and antiapoptotic effects by regulating endoplasmic reticulum stress.\u0026nbsp;BMC Complement Med Ther. 2023;23(1):35.\u003c/li\u003e\n \u003cli\u003eZhen LL, Hou MT, Wang SB. Salidroside attenuates sepsis-induced acute kidney injury by inhibiting ferroptosis. J Asian Nat Prod Res. 2025;2:1-15.\u003c/li\u003e\n \u003cli\u003eSong Y, Lin W, Zhu W. Traditional Chinese medicine for treatment of sepsis and related multi-organ injury. Front Pharmacol. 2023;14:1003658.\u003c/li\u003e\n \u003cli\u003eWang S, Zhao P, Zhang Y, et al. The Therapeutic Effects of Curcumin in Early Septic Acute Kidney Injury: An Experimental Study. Drug Des Devel Ther. 2021;15:4243-4255.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eYang T, Yu H, Xie Z. Curcumin-induced exosomal FTO from bone marrow stem cells alleviates sepsis-associated acute kidney injury by modulating the m6A methylation of OXSR1. Kaohsiung J Med Sci. 2025;41(2):e12923.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eHuang W, Li X, Wang D, et al. Curcumin reduces LPS-induced septic acute kidney injury through suppression of lncRNA PVT1 in mice.\u0026nbsp;Life Sci. 2020;254:117340.\u003c/li\u003e\n \u003cli\u003eZhang D, Tang Z, Huang H, et al. Metabolic regulation of gene expression by histone lactylation.\u0026nbsp;Nature. 2019;574(7779):575-580.\u003c/li\u003e\n \u003cli\u003eLi J, Shi X, Xu J, et al. Aldehyde Dehydrogenase 2 Lactylation Aggravates Mitochondrial Dysfunction by Disrupting PHB2 Mediated Mitophagy in Acute Kidney Injury.\u0026nbsp;Adv Sci (Weinh). 2025;12(8):e2411943.\u003c/li\u003e\n \u003cli\u003eQiao J, Tan Y, Liu H, et al. Histone H3K18 and Ezrin Lactylation Promote Renal Dysfunction in Sepsis-Associated Acute Kidney Injury. Adv Sci (Weinh). 2024;11(28):e2307216.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eGanner A, Pfeiffer ZC, Wingendorf L, et al. The acetyltransferase p300 regulates NRF2 stability and localization. Biochem Biophys Res Commun. 2020;524(4):895-902.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eYang L, Chen X, Bi Z, et al. Curcumin attenuates renal ischemia reperfusion injury via JNK pathway with the involvement of p300/CBP-mediated histone acetylation.\u0026nbsp;Korean J Physiol Pharmacol. 2021;25(5):413-423.\u003c/li\u003e\n \u003cli\u003eSunagawa Y, Funamoto M, Shimizu K, et al. Curcumin, an Inhibitor of p300-HAT Activity, Suppresses the Development of Hypertension-Induced Left Ventricular Hypertrophy with Preserved Ejection Fraction in Dahl Rats. Nutrients. 2021;13(8):2608.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eZhu H, Wang X, Wang X, et al. Curcumin attenuates inflammation and cell apoptosis through regulating NF-\u0026kappa;B and JAK2/STAT3 signaling pathway against acute kidney injury. Cell Cycle. 2020;19(15):1941-1951.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eCasserly B, Phillips GS, Schorr C, et al. Lactate measurements in sepsis-induced tissue hypoperfusion: results from the Surviving Sepsis Campaign database. Crit Care Med. 2015;43(3):567-573.\u003c/li\u003e\n \u003cli\u003eKim JY, Yee J, Yoon HY, Han JM, Gwak HS. Risk factors for vancomycin- associated acute kidney injury: A systematic review and meta-analysis.\u0026nbsp;Br J Clin Pharmacol. 2022;88(9):3977-3989.\u003c/li\u003e\n \u003cli\u003eTan C, Gu J, Li T, et al. Inhibition of aerobic glycolysis alleviates sepsis‑induced acute kidney injury by promoting lactate/Sirtuin 3/AMPK‑regulated autophagy.\u0026nbsp;Int J Mol Med. 2021;47(3):19.\u003c/li\u003e\n \u003cli\u003eZhu L, Zheng Q, Liu X, et al. HMGB1 lactylation drives neutrophil extracellular trap formation in lactate-induced acute kidney injury. Front Immunol. 2025;15:1475543.\u003c/li\u003e\n \u003cli\u003eQiao J, Tan Y, Liu H, et al. Histone H3K18 and Ezrin Lactylation Promote Renal Dysfunction in Sepsis-Associated Acute Kidney Injury. Adv Sci (Weinh). 2024;11(28):e2307216.\u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1: Renal Function and Inflammation Assessment at 24 h Post-CLP in Mice\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"480\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 14.6444%;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8996%;\"\u003e\n \u003cp\u003eScr\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(mmol/l)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.1088%;\"\u003e\n \u003cp\u003eUrea\u003c/p\u003e\n \u003cp\u003e(mmol/l)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.272%;\"\u003e\n \u003cp\u003eTNF-\u0026alpha;\u003c/p\u003e\n \u003cp\u003e(pg/ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.0628%;\"\u003e\n \u003cp\u003eIL-1\u0026beta;\u003c/p\u003e\n \u003cp\u003e(pg/ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 23.0126%;\"\u003e\n \u003cp\u003e\u0026nbsp;Serum Lactate\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 14.6444%;\"\u003e\n \u003cp\u003eSham\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8996%;\"\u003e\n \u003cp\u003e44.9\u0026plusmn;21.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.1088%;\"\u003e\n \u003cp\u003e35.4\u0026plusmn;7.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.272%;\"\u003e\n \u003cp\u003e192.0\u0026plusmn;105.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.0628%;\"\u003e\n \u003cp\u003e1390.6\u0026plusmn;466.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 23.0126%;\"\u003e\n \u003cp\u003e1.00\u0026plusmn;0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 14.6444%;\"\u003e\n \u003cp\u003eCLP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8996%;\"\u003e\n \u003cp\u003e311.0\u0026plusmn;39.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.1088%;\"\u003e\n \u003cp\u003e157.7\u0026plusmn;25.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.272%;\"\u003e\n \u003cp\u003e1257.0\u0026plusmn;312.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.0628%;\"\u003e\n \u003cp\u003e4212.9\u0026plusmn;676.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 23.0126%;\"\u003e\n \u003cp\u003e4.02\u0026plusmn;0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 14.6444%;\"\u003e\n \u003cp\u003eCLP+Cur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.8996%;\"\u003e\n \u003cp\u003e154.5\u0026plusmn;88.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.1088%;\"\u003e\n \u003cp\u003e103.6\u0026plusmn;17.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.272%;\"\u003e\n \u003cp\u003e359.6\u0026plusmn;109.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.0628%;\"\u003e\n \u003cp\u003e904.2\u0026plusmn;369.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 23.0126%;\"\u003e\n \u003cp\u003e2.76\u0026plusmn;0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2: Oxidative Stress and Cellular Activity Indicators at 24 h Post-LPS in HK-2\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003eMDA\u003c/p\u003e\n \u003cp\u003e(\u0026mu;mol/106)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003eCCK8\u003c/p\u003e\n \u003cp\u003e(OD 450 value)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21.7391%;\"\u003e\n \u003cp\u003eMedium Lactate\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003eSham\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003e0.54\u0026plusmn;0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003e1.43\u0026plusmn;0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21.7391%;\"\u003e\n \u003cp\u003e1.0\u0026plusmn;0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003eLPS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003e2.58\u0026plusmn;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003e0.72\u0026plusmn;0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21.7391%;\"\u003e\n \u003cp\u003e3.79\u0026plusmn;1.79\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003eLPS+Cur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003e1.11\u0026plusmn;0.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.087%;\"\u003e\n \u003cp\u003e1.12\u0026plusmn;0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21.7391%;\"\u003e\n \u003cp\u003e2.24\u0026plusmn;1.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-immunology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"imno","sideBox":"Learn more about [BMC Immunology](http://bmcimmunol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/imno/default.aspx","title":"BMC Immunology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7041963/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7041963/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study investigates the protective effects and underlying mechanisms of curcumin in sepsis-associated acute kidney injury (SA-AKI). Using a cecal ligation and puncture (CLP) model to simulate SA-AKI, our results demonstrate that curcumin significantly reduced serum creatinine and urea nitrogen levels, alleviated tubular damage and inflammation, improved cellular activity, and inhibited apoptosis. Further analysis revealed that curcumin inhibited the expression of p300 and decreased protein lactylation modification in renal tissue, thereby exerting anti-inflammatory and antioxidant effects. These findings suggest that curcumin may have potential therapeutic value for the prevention and treatment of SA-AKI.\u003c/p\u003e","manuscriptTitle":"Intervention Effect of Curcumin on Sepsis-Associated Acute Kidney Injury via Regulation of p300 Expression and Protein Lactylation","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-18 08:15:50","doi":"10.21203/rs.3.rs-7041963/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-07-28T06:09:30+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"61961457599679029109595685716195335734","date":"2025-07-26T12:57:35+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-25T07:25:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"300558738585561383865165863310534629100","date":"2025-07-24T12:47:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"309554025582939530663106113035701506216","date":"2025-07-24T10:20:19+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-21T12:23:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"63046351251213514540014662219443900862","date":"2025-07-16T07:43:12+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-13T06:34:23+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-12T22:23:35+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-07-11T08:34:57+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-11T08:09:50+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Immunology","date":"2025-07-11T08:06:31+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-immunology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"imno","sideBox":"Learn more about [BMC Immunology](http://bmcimmunol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/imno/default.aspx","title":"BMC Immunology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b4439da0-df84-442f-97b3-9c53757ca03a","owner":[],"postedDate":"July 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-09-29T16:00:15+00:00","versionOfRecord":{"articleIdentity":"rs-7041963","link":"https://doi.org/10.1186/s12865-025-00750-3","journal":{"identity":"bmc-immunology","isVorOnly":false,"title":"BMC Immunology"},"publishedOn":"2025-09-24 15:57:27","publishedOnDateReadable":"September 24th, 2025"},"versionCreatedAt":"2025-07-18 08:15:50","video":"","vorDoi":"10.1186/s12865-025-00750-3","vorDoiUrl":"https://doi.org/10.1186/s12865-025-00750-3","workflowStages":[]},"version":"v1","identity":"rs-7041963","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7041963","identity":"rs-7041963","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}