Fetal circulating human resistin increases in diabetes during pregnancy and impairs placental mitochondrial biogenesis

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Abstract Background: Diabetes during pregnancy affects placental mitochondrial content and function, which has the potential to impact fetal development and the long-term health of offspring. Resistin is a peptide hormone originally discovered in mice as an adipocyte-derived factor that induced insulin resistance. In humans, resistin is primarily secreted by monocytes or macrophages. The regulation and roles of human resistin in diabetes during pregnancy remain unclear. Methods: Fetal resistin levels were measured in cord blood from pregnancies with (n=42) and without maternal diabetes (n=81). Secretion of resistin from cord blood mononuclear cells (CBMCs) was measured. The actions of human resistin in mitochondrial biogenesis were determined in placental trophoblastic cells (BeWo cells) or human placental explant.Results: Concentrations of human resistin in cord sera were higher in diabetic pregnancies (67 ng/ml) compared to healthy controls (50 ng/ml, P< 0.05), and correlated (r=0.4, P=0.002) with a measure of maternal glycemia (glucose concentration 2 h post challenge). Resistin mRNA was most abundant in cord blood mononuclear cells (CBMCs) compared with placenta and mesenchymal stem cells (MSCs). Secretion of resistin from cultured CBMCs was increased in response to high glucose (25 mM). Exposing BeWo cells or human placental explant to resistin decreased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), mitochondrial abundance, and ATP production. Conclusions: Resistin is increased in fetal circulation of infants exposed to the diabetic milieu, potentially reflecting a response of monocytes/macrophages to hyperglycemia and metabolic stresses associated with diabetes during pregnancy. Increased exposure to resistin may contribute to mitochondrial dysfunction and aberrant energy metabolism characteristic of offspring exposed to diabetes in utero.
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Teague, Jeanie B. Tryggestad, Timothy J. Lyons, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-19051/v2 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 06 Aug, 2020 Read the published version in Molecular Medicine → Version 2 posted 3 You are reading this latest preprint version Show more versions Abstract Background: Diabetes during pregnancy affects placental mitochondrial content and function, which has the potential to impact fetal development and the long-term health of offspring. Resistin is a peptide hormone originally discovered in mice as an adipocyte-derived factor that induced insulin resistance. In humans, resistin is primarily secreted by monocytes or macrophages. The regulation and roles of human resistin in diabetes during pregnancy remain unclear. Methods: Fetal resistin levels were measured in cord blood from pregnancies with (n=42) and without maternal diabetes (n=81). Secretion of resistin from cord blood mononuclear cells (CBMCs) was measured. The actions of human resistin in mitochondrial biogenesis were determined in placental trophoblastic cells (BeWo cells) or human placental explant. Results: Concentrations of human resistin in cord sera were higher in diabetic pregnancies (67 ng/ml) compared to healthy controls (50 ng/ml, P< 0.05), and correlated (r=0.4, P=0.002) with a measure of maternal glycemia (glucose concentration 2 h post challenge). Resistin mRNA was most abundant in cord blood mononuclear cells (CBMCs) compared with placenta and mesenchymal stem cells (MSCs). Secretion of resistin from cultured CBMCs was increased in response to high glucose (25 mM). Exposing BeWo cells or human placental explant to resistin decreased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), mitochondrial abundance, and ATP production. Conclusions: Resistin is increased in fetal circulation of infants exposed to the diabetic milieu, potentially reflecting a response of monocytes/macrophages to hyperglycemia and metabolic stresses associated with diabetes during pregnancy. Increased exposure to resistin may contribute to mitochondrial dysfunction and aberrant energy metabolism characteristic of offspring exposed to diabetes in utero . Molecular Epidemiology Maternal & Fetal Medicine human resistin diabetes during pregnancy placenta mitochondria Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Background: Diabetes during pregnancy, including pre-gestational diabetes and gestational diabetes (GDM), affects fetal growth, which is linked to the development of obesity, diabetes, and cardiovascular diseases in later life (1-4). Approximately 16% of pregnant women globally have diabetes during pregnancy (International Diabetes Federation, Diabetes Atlas 9 th edition, 2019), and the percentage continues to increase, contributing significantly to the increased prevalence of diabetes and obesity in subsequent generations. The placenta plays a key role in fetal growth and development by supplying nutrients and oxygen. Diabetes during pregnancy alters placental structure and function with aberrant vascularization, increased inflammation, and impaired energy metabolism (5-7). As the interface between maternal and fetal circulation systems, the placenta can be affected by changes in both maternal and fetal circulating factors in response to the diabetic milieu (8). Resistin is a secreted protein implicated in the pathogenesis of obesity and type 2 diabetes. It was discovered in rodents as an adipocyte-derived factor which induces insulin resistance (9). Human and murine resistin only share 59% homology at the amino acid level (10). Unlike rodent resistin, human resistin is predominantly produced by peripheral blood mononuclear cells (PBMCs), macrophages, and bone marrow cells (11). Human resistin has been shown to induce expression of proinflammatory cytokines and adhesion molecules in the settings of inflammation and endothelial dysfunction. Given the strong relationship between inflammation and metabolism, there is mounting evidence suggesting a role for human resistin in the pathological processes of metabolic diseases, including obesity, diabetes, and cardiovascular diseases (12, 13). However, the precise mechanism by which resistin impacts these processes has not been clearly defined as several studies have failed to identify an association of resistin levels with obesity or type 2 diabetes (14, 15). Resistin has been implicated in the insulin resistance observed in normal pregnancy, as the level of resistin increases with gestational age and decreases after delivery (16). Conflicting evidence exists regarding the association of maternal resistin levels with GDM. Recent meta-analysis suggests GDM is associated with increased maternal resistin levels (17), while resutls of another meta-analysis do not indicate a significant change of resitin levels in gestational diabetes (18). Available prospective data are also inconsistent regarding the link of maternal resistin to the later development of GDM (19). Much less is known about fetal resistin levels and current studies examining the fetal levels of resistin in diabetes during pregnancy are inconsistent (20-22). The aims of the present study are to assess the regulation and function of human resistin in fetal circulation and how it affects placenta in diabetes during pregnancy. Our previous studies demonstrate that maternal diabetes is associated with decreased PGC-1α/TFAM/mitochondrial biogenesis signaling in human placenta (23). The present studies identify resistin as a potential mediator of that phenomenon by demonstrating increases in resistin concentration in the fetal circulation in pregnancies complicated by diabetes and inhibition of mitochondrial biogenesis and metabolism by resistin in the placenta. The production of resistin by fetal mononuclear cells reported here provides evidence for resistin as a link between the inflammatory response and energy metabolism in diabetes during pregnancy. Methods: Subjects for Cord serum Samples Pregnant Native American or Hispanic women with diabetes (N=42, including 31 gestational diabetes and 11 pre-gestational type 2 diabetes), or non-diabetic controls (N=81) were enrolled into a prospective longitudinal study on the impact of in utero exposure to DM, as previously described (24). Gestational or type 2 diabetes was diagnosed according to ADA guidelines (25). Women with type 2 diabetes were defined as those diagnosed before pregnancy. Women were excluded if they delivered prior to 37 weeks gestation, had type 1 diabetes, pre-eclampsia, chronic hypertension, renal disorders or a smoking history during pregnancy. They were also excluded if the infants were small for gestational age, had a major malformation, or chromosome abnormality. Maternal glucose concentrations measured 2 hours after oral glucose challenge (OGTT, Fig. 2) during the second trimester of pregnancy were obtained from clinical records. Cord blood and maternal blood (if available) were obtained after delivery, and cord and maternal serum resistin levels were measured. The protocol was approved by the Institutional Review Boards of the University of Oklahoma Health Science Center, the Chickasaw Nation, and the Choctaw Nation of Oklahoma. The samples collected under this protocol were not used for isolating cord blood mononuclear cells, mesenchymal stem cells, or placental explant culture. Studies using human cord blood mononuclear cells (CBMCs), mesenchymal stem cells (MSCs) and placental explant culture CBMCs, MSCs, and placental explants were isolated respectively from cord blood, cord tissue, or placenta obtained at term from healthy human subjects recruited in a separate study cohort as described previously (26). The protocol was approved by the Institutional Review Board of the University of Oklahoma Health Science Center. CBMCs were isolated from cord blood of non-diabetic healthy individuals by Ficoll density gradient centrifugation. The cord blood was diluted 1: 3 in PBS (without Ca 2+ and Mg 2+ ), layered over Ficoll buffer, and centrifuged at 400g for 35 minutes. The interphase cell layer was collected and washed in PBS for 3 times. The CBMCs were plated and cultured in Dulbecco's Modified Eagle Medium with 10% Fetal Bovine Serum followed by treatment with TNFα (100 ng/ml), high glucose (25 mM), palmitate acid (0.6 mM), or 4-hydroxynonenal (4-HNE, 0.6 mM) for 16 hours. Mesenchymal stem cells (MSCs) were isolated from Wharton’s Jelly of cord tissue as previously described (27). For Placental explant culture, two pieces of placental tissue were collected from healthy subjects within 15 minutes after delivery, stripped of connective tissues, and dissected to small pieces (about 2 mm). The placental villous explants were cultured in 6-well plate at 37°C in 5% CO 2 in Ham's F-12 medium (Gibco/Life Technologies, Grand Island, NY) supplemented with 10% FBS (Mediatech, Manassas, VA), 100 µM MEM Non-Essential Amino Acids (Gibco/Life Technologies, Grand Island, NY), and 0.5% penicillin/streptomycin/amphotericin B (Gibco/Life Technologies, Grand Island, NY) and were treated with indicated doses of resistin or vehicle for 24 hours in culture. ELISA The concentrations of resistin in serum and cell culture media were measured using human Resistin DuoSet ELISA kit (R&D Systems, Minneapolis, MN) according to manufacturer’s protocol. Briefly, ELISA plates were coated with capture antibody overnight at room temperature followed by blocking with Reagent Diluent (DuoSet ELISA Reagent Kit) for 2 hours. 100 ul cell culture media, or diluted fetal or maternal serum (1:40 in PBS), along with serial-diluted standards (0 - 4 ng/ml) were loaded to the plates and incubated overnight at 4 ºC, followed by adding detection antibody and streptavidin-HRP subsequently. Optical density was determined using a microplate reader at 450 nm. The detection range of the assay is 0.0625 ng/ml to 4 ng/ml with intraplate coefficient of variation of the duplicates less than 10% and inter-plate coefficient of variation less than 15%. RNA extraction Total RNA was extracted from BeWo cells (a human placental trophoblast cell line derived from a choriocarcinoma) using commercially available kits (miRNeasy, Qiagen, Valencia, CA) according to the manufacturer’s instructions. Isolated total RNA was quantified by a NanoDrop ND-1000 spectrophotometer (Thermo Scientific, Wilmington, DE). qPCR analysis Reverse transcription (RT) was done with SuperScript VILO cDNA Synthesis Kit according to the manufacturer’s instructions (Invitrogen). Quantitative real-time PCR was performed using TaqMan Real-Time PCR Probes for PGC-1α or GAPDH (Life Technologies). Results were calculated using the 2 −ΔΔCt method normalized to endogenous control GAPDH. Western Blot Analysis Western blot analysis was performed as described previously (23). Placental explant samples or BeWo cells were lysed and homogenized in protein lysis buffer containing a protease and phosphatase inhibitor cocktail (Pierce Biotechnology, Rockford, IL). Protein concentrations were measured by BCA assay (Pierce, Rockford, IL). Thirty µg of protein lysate was reduced in laemmli sample buffer with dithiothreitol, and subjected to sodium dodecyl sulfated polyacrylamide gel electrophoresis (SDS-PAGE), then transferred to polyvinylidene fluoride (PVDF) membrane and incubated with antibodies specific for PGC-1α, PDH, or β-actin (Cell Signaling Technology, Danvers, MA). The proteins of interest were detected by enhanced chemiluminescence (Pierce, Rockford, IL) and analyzed by imaging densitometry with Image Lab Software (Bio-Rad, Hercules, CA). Mitochondrial DNA copy number DNA was isolated from placental tissue using the GenElute Mammalian Genomic DNA Miniprep Kit (Sigma, St. Louis, MO) with proteinase K and RNase treatment, according to the manufacturer’s instructions. Mitochondrial DNA copy number was estimated by comparing the abundance of the mitochondrial tRNA Leu(UUR) gene (determined by quantitative RT-PCR, forward primer: 5’-CACCCAAGAACAGGGTTTGT; reverse: 5’-TGGCCATGGGTATGTTGTTA) and with that of the nuclear β2-microglobulin gene (forward: 5’-TGCTGTCTCCATGTTTGATGTATCT; reverse: 5’-TCTCTGCTCCCCACCTCTAAGT). ATP measurement: Cellular ATP levels were measured with Luminescent ATP detection assay kit (Abcam) according to manufacturer’s protocol. The cells were cultured in the medium containing galactose instead of glucose and the readings were normalized to DNA abundance measured by Sybrsafe staining. Statistical methods Group descriptive statistics are presented as mean ± SD and group count (percentage). The Kolmogorov-Smirnov test was used to test normality of the parameters (cord resistin, maternal Age, HbA1C, BMI, and gestational age). Among them, cord resistin, maternal age, and HbA1c were not normally distributed. Differences in characteristics between control and diabetic groups were assessed using Student’s t-test for normal distribution and nonparametric Mann-Whitney test for non-normal distribution. Maternal glucose (OGTT-2 hours) and maternal factors which displayed significant difference between control and diabetic groups, including maternal age, HbA1C, BMI, and gestational age, were subjected to correlation analysis with cord resistin. Spearman correlations were used for correlation analysis for non-normal distributions. Multiple regression analysis was conducted to further assess relationships after controlling multiple variables. In the multiple regression model, cord resistin was the dependent variable and study groups (control and diabetes), maternal age, BMI and gestational age were the independent variables. The statistical analysis were performed in Excel, GraphPad Prism, and SPSS. For all analysis, P-values <0.05 were treated as statistically significant. Results: Cord blood resistin concentration is increased in offspring born to mothers with diabetes during pregnancy and correlates with maternal blood glucose levels Demographics for participants providing cord blood samples are shown in Table 1. The participants with diabetes during pregnancy were older, had higher HBA1C, BMI, and slightly lower gestational age. There was no significant difference in the ethnicity and fetal sex between pregnant women with or without diabetes. Table 1: Characteristics of Research Subjects Providing Cord Blood Samples DM N=42 (Male 21; Female 21) Control N=81 (Male 37; Female 44) P-value (DM vs Control) Maternal Age, Y 31±5.9 24.47±4.4 P<0.001 Maternal HbA1C, % 5.68±0.74 5.15±0.28 P<0.001 Maternal BMI 32.74±6.3 28.22±6.77 P<0.01 Gestational age, weeks 38.89±0.66 39.55±0.95 P0.05 Hispanic 18 (43%) 25 (31%) The level of resistin in cord blood of infants born to mothers with diabetes (67.3 ± 48.4 ng/ml, n=42) were significantly higher (P=0.03) than those born to control women (50.4 ± 35.2 ng/ml, n=81) (Figure 1A). Cord blood resistin levels were significantly higher compared to the corresponding maternal blood resistin levels in control (Fig. 1B) and women with diabetes (Fig. 1C). Concentrations of human resistin in cord sera correlated significantly (R=0.4, P=0.002) with maternal glucose concentrations measured 2 hours after oral glucose challenge (OGTT, Fig. 2) during the second trimester of pregnancy. The correlation of cord blood resistin concentrations with maternal HbA1C at delivery was approaching significance (P=0.057), whereas there were no significant correlations between cord blood resistin with maternal age, BMI, or gestational age at Table 2: Spearman tests on correlation of maternal factors with Cord blood Resistin levels birth (Table 2). R (Correlation Coefficient with Cord resistin) Correlation with Cord resistin Maternal Age, Y 0.082 P>0.1 Maternal HbA1C, % 0.207 P=0.057 Maternal BMI 0.028 P>0.1 Gestational age, weeks 0.059 P>0.1 Dependable Variable: human Cord resistin Variable Standardized Coefficients Beta Significance (P) Diabetes During Pregnancy 0.279 P=0.03* Maternal Age 0.035 P>0.1 Maternal BMI 0.028 P>0.1 Gestational age 0.059 P>0.1 Table3: Multiple regression analysis on the variables Multiple regression analysis was conducted to further examine the relationship between fetal resistin and multiple variables. As shown in Table 3, only the presence of maternal diabetes reached significance in the regression model, indicating maternal age, BMI, and gestational age did not contribute to the different resistin levels between control and diabetic groups observed here. Secretion of resistin from cord blood mononuclear cells in response to metabolic stresses The expression of resistin mRNA in fetal tissues and cells was examined by quantitative real-time PCR. As shown in Figure 3A, resistin was highly expressed in cord blood mononuclear cells (CBMCs). Placenta also expressed resistin but at much lower abundance, whereas expression of resistin was not detectable in mesenchymal stem cells isolated from umbilical cord Wharton’s Jelly, nor in BeWo cells, a placental trophoblast cell line (Figure 3A). Treating CBMCs with high glucose, palmitate, or the inflammatory factor TNFα, but not the oxidative stress inducer 4-HNE, resulted in increased levels of resistin in the culture media (Figure 3B). Human resistin inhibits placental mitochondrial biogenesis We previously reported a decrease in the PGC-1α/TFAM mitochondrial biogenesis pathway in placenta of mothers with diabetes (23). Treating human placental explants with resistin resulted in a maximal decrease in PGC-1α protein abundance at 100 ng/ml (Figure 4A) accompanied by a significant decrease in mitochondrial DNA copy number (Figure 4B), demonstrating the capacity of resistin to regulate placental mitochondrial biogenesis. Human resistin decreases PGC-1α and mitochondrial energy metabolism in placental trophoblasts Trophoblasts are the placental cells which provide the major source of nutrients for the growing embryos. In a transformed trophoblast cell line, BeWo cells, human resistin treatment also decreased the PGC-1α protein abundance (Figure 5A) and its mRNA expression (Figure 5B). In addition, the protein level of pyruvate dehydrogenase (PDH) was decreased by resistin treatment (Figure 5A). Resistin also inhibited cellular ATP production (Figure 5D), further demonstrating the influence of resistin on mitochondrial energy metabolism. Discussion: An adverse maternal environment, such as diabetes during pregnancy, impacts fetal and placental development, which is associated with increased risk of metabolic diseases in offspring later in life (1-4). The present study demonstrates that an increase in cord blood resistin found in the presence of maternal diabetes may play a role in placental mitochondrial biogenesis and function. A recent meta-analysis of 18 published studies (17) notes that resistin levels are elevated in maternal circulation in gestational diabetes. Much less is known about the determinants of resistin abundance in the fetal circulation and current reports regarding the association between cord blood resistin with diabetes during pregnancy are discordant (20-22). The present study found an increase in cord blood resistin in maternal diabetes, which agrees with the reports by Shang et al and Oncul et al (20, 21). We also demonstrated that resistin expression was highly enriched in cord blood mononuclear cells, suggesting that fetal mononuclear cells may be the main source of fetal circulating resistin. We, along with others (16, 28), detect expression of resistin in the placenta. However, we found much lower abundance there compared to that in mononuclear cells. As no expression was detected in the placental trophoblast cell line, BeWo, we suspect that placental macrophages, rather than trophoblasts, are responsible for placental resistin expression. In addition to cord blood resistin concentration being higher in pregnancies complicated by diabetes, a positive correlation with maternal blood glucose levels was found. Hyperglycemia and hyperinsulinemia in GDM are known to activate inflammatory cells and induce a pro-inflammatory status (29). In accord, we found that cord blood mononuclear cells secreted resistin in response to exposure to high glucose and other diabetes-related factors. Thus, our findings further characterize resistin as an inflammatory cell-derived factor that responds to hyperglycemia and metabolic stresses associated with diabetic pregnancy. Our study begins to examine potential functions of resistin in the fetus, suggesting involvement in regulation of placental mitochondrial abundance and function. Mitochondria play a key role in placental function, and defects in placental mitochondrial function and content are associated with impaired placental energetics and increased oxidative stress, which lead to adverse pregnancy outcomes (30-32). We previously demonstrated a decrease in PGC-1α/TFAM/mitochondrial biogenesis signaling in placenta of women with diabetes during pregnancy (23). Here we observed decreases in PGC-1α expression and mitochondrial DNA copy number when human placental explants were exposed to resistin. In addition, resistin treatment reduced the abundance of pyruvate dehydrogenase (PDH) and ATP production. Pyruvate dehydrogenase is a mitochondrial enzyme that catalyzes pyruvate oxidation, linking glycolysis to the Krebs cycle for ATP generation to meet energy demands (33). Mitochondria are the primary source of ATP needed for placental growth, nutrient transport, and hormone synthesis. Therefore, increased expression of resistin may contribute to impaired placental mitochondrial biogenesis and function, as well as offspring adverse outcomes in pregnancies complicated by diabetes. The strengths of the present study are identification of resistin as a fetal factor derived from inflammatory cells that is affected by maternal diabetes and demonstration of a role for resistin in inhibiting placental mitochondrial metabolism. Limitations of the present study are that the specific downstream signaling underlying resistin effects on mitochondrial biogenesis and the roles of resistin on other fetal tissues remain to be explored. Four distinct receptors have been identified to bind to resistin, including Toll-like receptor 4 (TLR4), decorin, receptor tyrosine kinase-like orphan receptor 1 (ROR1), and adenylyl cyclase-associated protein 1 (CAP1) (34-36). Resistin/TLR4 has been shown to inhibit AMP activated kinase (AMPK)(35, 37), an important regulator of mitochondrial biogenesis(37). TLR4 and AMPK inhibition can be the potential mechanism underlying resistin-induced decrease in placental mitochondrial metabolism. However, which of these receptors and the specific downstream pathways responsible for the effects of resistin on mitochondrial metabolism remains to be investigated. In addition, elevated fetal resistin can potentially impact energy metabolism and development of other fetal tissues, such as muscle, which remain to be studied. Conclusions: Here we provide evidence that resistin acts as a circulating factor linking inflammation and energy metabolism during fetal life and that it may contribute to impaired placental mitochondrial metabolism in maternal diabetes. As much remains to be learned about the role of resistin during fetal life, the clinical implications of these findings await future studies and definition. However, maternal diabetes has both immediate and long-term effects on the offspring which are tied to energy management and mitochondrial function. Thus, human resistin could be a potential therapeutic target or a diagnostic marker for the short-term and long-term adverse pregnancy outcomes of diabetes during pregnancy. Abbreviations cord blood mononuclear cells (CBMCs); peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α); gestational diabetes (GDM); 4-Hydroxynonenal (4-HNE); pyruvate dehydrogenase (PDH). Declarations Ethics approval and consent to participate: The studies on human cord serum samples (IRB protocol#1267), and the CBMCs and placental explants (IRB #2540) were approved by the Institutional Review Boards of the University of Oklahoma Health Science Center, the Chickasaw Nation, and the Choctaw Nation of Oklahoma. Author contributions: All authors contributed to the conception, design and interpretation of the data. SJ, AMT, and JBT performed the experiments. SJ and SDC wrote the manuscript. All authors revised the manuscript and approved this version to be published. Acknowledgements and funding: We thank study coordinators Mary Ayn Tullier, Justin Fowler, Olufolake Olufowote and Shelly Hopper; the Choctaw Nation of Oklahoma and the Chickasaw Nation; and our study participants and families. This study was supported by NIH Grants R01 DK089034-05 (S. Chernausek, PI), P20 MD000528-05 (T. Lyons, Project PI), and NIH K23 award (PI: J. Tryggestad-K23DK106533); American Diabetes Association Grant 1-10-CT-09 (S. Chernausek, PI); the OCAST (S. Jiang); and OK-INBRE Grant (RPI: S. Jiang). Declarations: There is no conflict of interest associated with this manuscript. The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. References Fetita LS, Sobngwi E, Serradas P, Calvo F, Gautier JF. (2006) Consequences of fetal exposure to maternal diabetes in offspring. J Clin Endocrinol Metab 91: 3718-3724. Dabelea D, Crume T. (2011) Maternal environment and the transgenerational cycle of obesity and diabetes. Diabetes 60: 1849-1855. Damm P , et al. (2016) Gestational diabetes mellitus and long-term consequences for mother and offspring: a view from Denmark. Diabetologia 59: 1396-1399. Friedman JE. (2018) Developmental Programming of Obesity and Diabetes in Mouse, Monkey, and Man in 2018: Where Are We Headed? Diabetes 67: 2137-2151. Jarmuzek P, Wielgos M, Bomba-Opon D. (2015) Placental pathologic changes in gestational diabetes mellitus. Neuro Endocrinol Lett 36: 101-105. Osmond DT, Nolan CJ, King RG, Brennecke SP, Gude NM. (2000) Effects of gestational diabetes on human placental glucose uptake, transfer, and utilisation. Diabetologia 43: 576-582. Muralimanoharan S, Maloyan A, Myatt L. (2016) Mitochondrial function and glucose metabolism in the placenta with gestational diabetes mellitus: role of miR-143. Clin Sci (Lond) 130: 931-941. Desoye G, Hauguel-de Mouzon S. (2007) The human placenta in gestational diabetes mellitus. The insulin and cytokine network. Diabetes Care 30 Suppl 2: S120-126. Steppan CM , et al. (2001) The hormone resistin links obesity to diabetes. Nature 409: 307-312. Ghosh S, Singh AK, Aruna B, Mukhopadhyay S, Ehtesham NZ. (2003) The genomic organization of mouse resistin reveals major differences from the human resistin: functional implications. Gene 305: 27-34. Schwartz DR, Lazar MA. (2011) Human resistin: found in translation from mouse to man. Trends Endocrinol Metab 22: 259-265. Lazar MA. (2007) Resistin- and Obesity-associated metabolic diseases. Horm Metab Res 39: 710-716. McTernan CL , et al. (2002) Resistin, central obesity, and type 2 diabetes. Lancet 359: 46-47. Gerber M , et al. (2005) Serum resistin levels of obese and lean children and adolescents: biochemical analysis and clinical relevance. J Clin Endocrinol Metab 90: 4503-4509. Pfutzner A, Langenfeld M, Kunt T, Lobig M, Forst T. (2003) Evaluation of human resistin assays with serum from patients with type 2 diabetes and different degrees of insulin resistance. Clin Lab 49: 571-576. Chen D , et al. (2005) Alterations of serum resistin in normal pregnancy and pre-eclampsia. Clin Sci (Lond) 108: 81-84. Hu SM, Chen MS, Tan HZ. (2019) Maternal serum level of resistin is associated with risk for gestational diabetes mellitus: A meta-analysis. World J Clin Cases 7: 585-599. Bellos I, Fitrou G, Pergialiotis V, Perrea DN, Daskalakis G. (2019) Serum levels of adipokines in gestational diabetes: a systematic review. J Endocrinol Invest 42: 621-631. Bao W , et al. (2015) Adipokine levels during the first or early second trimester of pregnancy and subsequent risk of gestational diabetes mellitus: A systematic review. Metabolism 64: 756-764. Shang M, Dong X, Hou L. (2018) Correlation of adipokines and markers of oxidative stress in women with gestational diabetes mellitus and their newborns. J Obstet Gynaecol Res 44: 637-646. Oncul M , et al. (2013) Maternal and cord blood apelin, resistin and visfatin levels in gestational diabetes mellitus. Minerva Med 104: 527-535. Mohamed MH , et al. (2010) Cord blood resistin and adiponectin in term newborns of diabetic mothers. Arch Med Sci 6: 558-566. Jiang S , et al. (2017) Effects of maternal diabetes and fetal sex on human placenta mitochondrial biogenesis. Placenta 57: 26-32. Teague AM , et al. (2015) Cord blood adipokines, neonatal anthropometrics and postnatal growth in offspring of Hispanic and Native American women with diabetes mellitus. Reprod Biol Endocrinol 13: 68. American Diabetes A. (2003) Gestational diabetes mellitus. Diabetes Care 26 Suppl 1: S103-105. Shaoning Jiang AMT, Jeanie B. Tryggestad, Mary E. Jensen, and Steven D. Chernausek. (2020) Role of metformin in epigenetic regulation of placental mitochondrial biogenesis in maternal diabetes. In: Scientific Reports. Boyle KE , et al. (2016) Mesenchymal Stem Cells From Infants Born to Obese Mothers Exhibit Greater Potential for Adipogenesis: The Healthy Start BabyBUMP Project. Diabetes 65: 647-659. Erol O , et al. (2016) Serum level and placental expression of resistin in pregnancies complicated by preeclampsia: relationship with disease severity. Clin Exp Obstet Gynecol 43: 516-521. Pantham P, Aye IL, Powell TL. (2015) Inflammation in maternal obesity and gestational diabetes mellitus. Placenta 36: 709-715. Mando C , et al. (2018) Impact of Obesity and Hyperglycemia on Placental Mitochondria. Oxid Med Cell Longev 2018: 2378189. Clemente DBP , et al. (2017) Prenatal ambient air pollution exposure, infant growth and placental mitochondrial DNA content in the INMA birth cohort. Environ Res 157: 96-102. Bijnens EM , et al. (2019) Placental mitochondrial DNA content is associated with childhood intelligence. J Transl Med 17: 361. Park S , et al. (2018) Role of the Pyruvate Dehydrogenase Complex in Metabolic Remodeling: Differential Pyruvate Dehydrogenase Complex Functions in Metabolism. Diabetes Metab J 42: 270-281. Zhao CW , et al. (2019) An Update on the Emerging Role of Resistin on the Pathogenesis of Osteoarthritis. Mediators Inflamm 2019: 1532164. Miao J , et al. (2018) Resistin inhibits neuronal autophagy through Toll-like receptor 4. J Endocrinol 238: 77-89. Lee S , et al. (2014) Adenylyl cyclase-associated protein 1 is a receptor for human resistin and mediates inflammatory actions of human monocytes. Cell Metab 19: 484-497. Hardie DG. (2007) AMP-activated/SNF1 protein kinases: conserved guardians of cellular energy. Nat Rev Mol Cell Biol 8: 774-785. Cite Share Download PDF Status: Published Journal Publication published 06 Aug, 2020 Read the published version in Molecular Medicine → Version 2 posted Editor assigned by journal 16 Jun, 2020 Submission checks completed at journal 15 Jun, 2020 Editor invited by journal 15 Jun, 2020 You are reading this latest preprint version Show more versions 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-19051","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research article","associatedPublications":[],"authors":[{"id":674665,"identity":"7ffa4b7b-353d-4d4a-b111-4498dace145a","order_by":0,"name":"Shaoning Jiang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABB0lEQVRIiWNgGAWjYDACCRBhACIONgAJG6gIAzPRWtKI1YIAhwlrkZ/d/PBxQcEduwbGw42fC36dlzO43f7wA0OFdWIDDi0Gd44ZG88weJbcwHCwWXpm321jgztnjCUYzqTj1iKRYCbNY3A42f7AwQZp3p7biRtu5LAxMLYdxqlFfkb6N7AWoPebf/P2nANqSX/GwPgPtxaGGzlgW+yAWtqkeX4cAGpJMGNgbMCtxeBGTrExUEsCSIs1b0OyseSNHGOJhGPpxngctvExz5/D9gwSxx/f5vljJ8d3I/3hhw811rI4HQYFiQ0SBxiAvoZyEwgoBwF7Bn6QqX+IUDoKRsEoGAUjDgAACM5fYesRBFYAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0001-6445-9900","institution":"University of Oklahoma","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Shaoning","middleName":"","lastName":"Jiang","suffix":""},{"id":674666,"identity":"f8abdb6a-715c-4941-a1b0-d45605e56087","order_by":1,"name":"April M. Teague","email":"","orcid":"","institution":"University of Oklahoma","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"April","middleName":"M.","lastName":"Teague","suffix":""},{"id":674667,"identity":"ffa18a6f-7445-44e4-afc0-d8b39308f967","order_by":2,"name":"Jeanie B. Tryggestad","email":"","orcid":"","institution":"University of Oklahoma","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jeanie","middleName":"B.","lastName":"Tryggestad","suffix":""},{"id":674668,"identity":"1da55f53-66f9-4156-9bb4-1566453091db","order_by":3,"name":"Timothy J. Lyons","email":"","orcid":"","institution":"University of south carolina","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Timothy","middleName":"J.","lastName":"Lyons","suffix":""},{"id":674669,"identity":"8aa55b5c-d61f-4625-a1a2-b51393512dea","order_by":4,"name":"Steven D. Chernausek","email":"","orcid":"","institution":"University of Oklahoma","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Steven","middleName":"D.","lastName":"Chernausek","suffix":""}],"badges":[],"createdAt":"2020-03-24 10:47:47","currentVersionCode":2,"declarations":"","doi":"10.21203/rs.3.rs-19051/v2","doiUrl":"https://doi.org/10.21203/rs.3.rs-19051/v2","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s10020-020-00205-y","type":"published","date":"2020-08-06T12:00:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":1356306,"identity":"bdb3f0b2-b77c-46c4-9671-6032624e7d9a","added_by":"auto","created_at":"2020-06-17 20:49:23","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":234900,"visible":true,"origin":"","legend":"Serum resistin levels in cord and maternal blood. (A) Resistin concentrations were higher in the cord blood of diabetic women (DM) compared to healthy controls (Mean ± SD, * P\u003c0.05, N=81 in control, N=42 in DM); (B and C) Pairwise comparison of resistin levels in maternal and cord blood. N= 9 pairs of control (B) and N=15 pairs of Diabetes (C), ** P\u003c0.01 between maternal and cord levels.","description":"","filename":"Fig1300dpismall.jpg","url":"https://assets-eu.researchsquare.com/files/rs-19051/v2/Fig1300dpismall.jpg"},{"id":1356307,"identity":"73905f56-ef54-4d92-b992-550b19cca50e","added_by":"auto","created_at":"2020-06-17 20:49:23","extension":"tif","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":256975,"visible":true,"origin":"","legend":"Correlation between cord blood human resistin and maternal blood glucose levels during pregnancy. Cord blood resistin levels were determined as described in methods. Maternal glucose concentration was measured at 2 h during the second trimester OGTT. N= 59 including 43 control mothers and 16 with diabetes.","description":"","filename":"Fig2300dpismall.tif","url":"https://assets-eu.researchsquare.com/files/rs-19051/v2/Fig2300dpismall.tif"},{"id":1356308,"identity":"8fd1cdb4-ed7c-4a00-999b-a141d7f9bee2","added_by":"auto","created_at":"2020-06-17 20:49:24","extension":"tif","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":366340,"visible":true,"origin":"","legend":"Secretion of resistin from cord blood mononuclear cells in response to metabolic stresses. (A) Expression of resistin mRNA in placenta and cord blood mononuclear cells (CBMCs), cord tissue mesenchymal stem cells (MSC) of healthy subjects (N=5 subjects for placental tissues and CBMCs; N=3 subjects for MSCs), and BeWo cells (trophoblast cell line) were measured by quantitative RT-PCR; (B) Mononuclear cells were isolated from cord blood of healthy pregnant women and were treated with TNFα (100 ng/ml), high glucose (25 mM), palmitate acid (0.6 mM), or 4-Hydroxynonenal (4-HNE, 0.6 mM) for 16 hours, followed by measuring resistin levels in culture media with ELISA. M: mannitol treated group as an osmotic control for high group treatment. Mean ± SD, ** P\u003c0.01; *** P\u003c0.001; N=4.","description":"","filename":"Fig3300dpismall.tif","url":"https://assets-eu.researchsquare.com/files/rs-19051/v2/Fig3300dpismall.tif"},{"id":1356309,"identity":"105654b2-3a7b-42b1-b8b4-defe67fda845","added_by":"auto","created_at":"2020-06-17 20:49:24","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":211477,"visible":true,"origin":"","legend":"Effect of resistin on mitochondrial biogenesis in placentae. Human placental explants were treated with indicated doses of human resistin for 24 hours. (A) protein lysates were subjected for Western blot analysis; (B) total DNA were extracted and mitochondrial DNA copy number was determined by fold change of mitochondrial tRNALeu(UUR) gene DNA copy number normalized to nuclear β2 microglobin (B2M) with quantitative RT-PCR. Mean ± SD, ** P\u003c0.01; *** P\u003c0.001; N=4. # P\u003c0.05 with one-tail T-test.","description":"","filename":"Fig4300dpismall.jpg","url":"https://assets-eu.researchsquare.com/files/rs-19051/v2/Fig4300dpismall.jpg"},{"id":1356310,"identity":"df7e3828-956a-487e-92b9-8966d66d456f","added_by":"auto","created_at":"2020-06-17 20:49:24","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":299351,"visible":true,"origin":"","legend":"Effect of resistin on PGC-1α and mitochondrial metabolism in placental trophoblasts. BeWo cells were treated with indicated doses of human resistin for 24 hours. (A) Protein lysates were subjected for Western blot analysis (N=4 in each group); (B) total RNAs were reverse-transcribed and subjected for RT-PCR (N=4 in each group); (C) BeWo cells were treated with indicated doses of human resistin in medium containing galactose for 24 hrs followed by assay for ATP levels (N=8 in each group). Mean ± SD * P\u003c0.05; ** P\u003c0.01.\n\n","description":"","filename":"Fig5300dpismall.jpg","url":"https://assets-eu.researchsquare.com/files/rs-19051/v2/Fig5300dpismall.jpg"},{"id":13542835,"identity":"81e416d1-70d0-4544-a422-bc221c6d15cc","added_by":"auto","created_at":"2021-09-17 01:55:56","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1153086,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-19051/v2/49f239a0-3e7c-44aa-908a-6815780dd979.pdf"}],"financialInterests":"","formattedTitle":"Fetal circulating human resistin increases in diabetes during pregnancy and impairs placental mitochondrial biogenesis","fulltext":[{"header":"Background:","content":"\u003cp\u003eDiabetes during pregnancy, including pre-gestational diabetes and gestational diabetes (GDM), affects fetal growth, which is linked to the development of obesity, diabetes, and cardiovascular diseases in later life (1-4). Approximately 16% of pregnant women globally have diabetes during pregnancy (International Diabetes Federation, Diabetes Atlas 9\u003csup\u003eth\u003c/sup\u003e edition, 2019), and the percentage continues to increase, contributing significantly to the increased prevalence of diabetes and obesity in subsequent generations. The placenta plays a key role in fetal growth and development by supplying nutrients and oxygen. Diabetes during pregnancy alters placental structure and function with aberrant vascularization, increased inflammation, and impaired energy metabolism (5-7). As the interface between maternal and fetal circulation systems, the placenta can be affected by changes in both maternal and fetal circulating factors in response to the diabetic milieu (8).\u003c/p\u003e\n\u003cp\u003eResistin is a secreted protein implicated in the pathogenesis of obesity and type 2 diabetes. It was discovered in rodents as an adipocyte-derived factor which induces insulin resistance (9). Human and murine resistin only share 59% homology at the amino acid level (10). Unlike rodent resistin, human resistin is predominantly produced by peripheral blood mononuclear cells (PBMCs), macrophages, and bone marrow cells (11). Human resistin has been shown to induce expression of proinflammatory cytokines and adhesion molecules in the settings of inflammation and endothelial dysfunction. Given the strong relationship between inflammation and metabolism, there is mounting evidence suggesting a role for human resistin in the pathological processes of metabolic diseases, including obesity, diabetes, and cardiovascular diseases (12, 13). However, the precise mechanism by which resistin impacts these processes has not been clearly defined as several studies have failed to identify an association of resistin levels with obesity or type 2 diabetes (14, 15). Resistin has been implicated in the insulin resistance observed in normal pregnancy, as the level of resistin increases with gestational age and decreases after delivery (16). Conflicting evidence exists regarding the association of maternal resistin levels with GDM. Recent meta-analysis suggests GDM is associated with increased maternal resistin levels (17), while resutls of another meta-analysis do not indicate\u0026nbsp; a significant change of resitin levels in gestational diabetes (18). Available prospective data are also inconsistent regarding the link of maternal resistin to the later development of GDM (19). Much less is known about fetal resistin levels and current studies examining the fetal levels of resistin in diabetes during pregnancy are inconsistent (20-22). The aims of the present study are to assess the regulation and function of human resistin in fetal circulation and how it affects placenta in diabetes during pregnancy.\u003c/p\u003e\n\u003cp\u003eOur previous studies demonstrate that maternal diabetes is associated with decreased PGC-1\u0026alpha;/TFAM/mitochondrial biogenesis signaling in human placenta (23). The present studies identify\u0026nbsp;\u0026nbsp; \u0026nbsp;resistin as a potential mediator of that phenomenon by demonstrating increases in resistin concentration in the fetal circulation in pregnancies complicated by diabetes and inhibition of mitochondrial biogenesis and metabolism by resistin in the placenta. The production of resistin by fetal mononuclear cells reported here provides evidence for resistin as a link between the inflammatory response and energy metabolism in diabetes during pregnancy.\u003c/p\u003e"},{"header":"Methods:","content":"\u003cp\u003e\u003cem\u003eSubjects for Cord serum Samples\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePregnant Native American or Hispanic women with diabetes (N=42, including 31 gestational diabetes and 11 pre-gestational type 2 diabetes), or non-diabetic controls (N=81) were enrolled into a prospective longitudinal study on the impact of \u003cem\u003ein utero\u003c/em\u003e exposure to DM, as previously described (24). Gestational or type 2 diabetes was diagnosed according to ADA guidelines (25). Women with type 2 diabetes were defined as those diagnosed before pregnancy. Women were excluded if they delivered prior to 37 weeks gestation, had type 1 diabetes, pre-eclampsia, chronic hypertension, renal disorders or a smoking history during pregnancy. They were also excluded if the infants were small for gestational age, had a major malformation, or chromosome abnormality. Maternal glucose concentrations measured 2 hours after oral glucose challenge (OGTT, Fig. 2) during the second trimester of pregnancy were obtained from clinical records. Cord blood and maternal blood (if available) were obtained after delivery, and cord and maternal serum resistin levels were measured. The protocol was approved by the Institutional Review Boards of the University of Oklahoma Health Science Center, the Chickasaw Nation, and the Choctaw Nation of Oklahoma. The samples collected under this protocol were not used for isolating cord blood mononuclear cells, mesenchymal stem cells, or placental explant culture.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStudies using human cord blood mononuclear cells (CBMCs), mesenchymal stem cells (MSCs) and placental explant culture\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eCBMCs, MSCs, and placental explants were isolated respectively from cord blood, cord tissue, or placenta obtained at term from healthy human subjects recruited in a separate study cohort as described previously (26). The protocol was approved by the Institutional Review Board of the University of Oklahoma Health Science Center. CBMCs were isolated from cord blood of non-diabetic healthy individuals by Ficoll density gradient centrifugation. The cord blood was diluted 1: 3 in PBS (without Ca\u003csup\u003e2+\u003c/sup\u003e and Mg\u003csup\u003e2+\u003c/sup\u003e), layered over Ficoll buffer, and centrifuged at 400g for 35 minutes. The interphase cell layer was collected and washed in PBS for 3 times. The CBMCs were plated and cultured in Dulbecco's Modified Eagle\u0026nbsp;Medium with 10% Fetal Bovine Serum followed by treatment with TNF\u0026alpha; (100 ng/ml), high glucose (25 mM), palmitate acid (0.6 mM), or 4-hydroxynonenal (4-HNE, 0.6 mM) for 16 hours. Mesenchymal stem cells (MSCs) were isolated from Wharton\u0026rsquo;s Jelly of cord tissue as previously described (27). For Placental explant culture, two pieces of placental tissue were collected from healthy subjects within 15 minutes after delivery, stripped of connective tissues, and dissected to small pieces (about 2 mm). The placental villous explants were cultured in 6-well plate at 37\u0026deg;C in 5% CO\u003csub\u003e2\u003c/sub\u003e in Ham's F-12 medium (Gibco/Life Technologies, Grand Island, NY) supplemented with 10% FBS (Mediatech, Manassas, VA), 100 \u0026micro;M MEM Non-Essential Amino Acids (Gibco/Life Technologies, Grand Island, NY), and 0.5% penicillin/streptomycin/amphotericin B (Gibco/Life Technologies, Grand Island, NY) and were treated with indicated doses of resistin or vehicle for 24 hours in culture.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eELISA\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe concentrations of resistin in serum and cell culture media were measured using human Resistin DuoSet ELISA kit (R\u0026amp;D Systems, Minneapolis, MN) according to manufacturer\u0026rsquo;s protocol. Briefly, ELISA plates were coated with capture antibody overnight at room temperature followed by blocking with Reagent Diluent (DuoSet ELISA Reagent Kit) for 2 hours. 100 ul cell culture media, or diluted fetal or maternal serum (1:40 in PBS), along with serial-diluted standards (0 - 4 ng/ml) were loaded to the plates and incubated overnight at 4 \u0026ordm;C, followed by adding detection antibody and streptavidin-HRP subsequently. Optical density was determined using a microplate reader at 450 nm. The detection range of the assay is 0.0625 ng/ml to 4 ng/ml with intraplate coefficient of variation of the duplicates less than 10% and inter-plate coefficient of variation less than 15%.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eRNA extraction\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; Total RNA was extracted from BeWo cells (a human placental trophoblast cell line derived from a choriocarcinoma) using commercially available kits (miRNeasy, Qiagen, Valencia, CA) according to the manufacturer\u0026rsquo;s instructions. Isolated total RNA was quantified by a NanoDrop ND-1000 spectrophotometer (Thermo Scientific, Wilmington, DE).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eqPCR analysis\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eReverse transcription (RT) was done with SuperScript VILO cDNA Synthesis Kit according to the manufacturer\u0026rsquo;s instructions (Invitrogen). Quantitative real-time PCR was performed using TaqMan Real-Time PCR Probes for PGC-1\u0026alpha; or GAPDH (Life Technologies). Results were calculated using the 2\u003csup\u003e\u0026minus;\u0026Delta;\u0026Delta;Ct\u003c/sup\u003e method normalized to endogenous control GAPDH.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eWestern Blot Analysis \u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eWestern blot analysis was performed as described previously (23). Placental explant samples or BeWo cells were lysed and homogenized in protein lysis buffer containing a protease and phosphatase inhibitor cocktail (Pierce Biotechnology, Rockford, IL). Protein concentrations were measured by BCA assay (Pierce, Rockford, IL). Thirty \u0026micro;g of protein lysate was reduced in laemmli sample buffer with dithiothreitol, and subjected to sodium dodecyl sulfated polyacrylamide gel electrophoresis (SDS-PAGE), then transferred to polyvinylidene fluoride (PVDF) membrane and incubated with antibodies specific for PGC-1\u0026alpha;, PDH, or \u0026beta;-actin (Cell Signaling Technology, Danvers, MA). The proteins of interest were detected by enhanced chemiluminescence (Pierce, Rockford, IL) and analyzed by imaging densitometry with Image Lab Software (Bio-Rad, Hercules, CA).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eMitochondrial DNA copy number \u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eDNA was isolated from placental tissue using the GenElute Mammalian Genomic DNA Miniprep Kit (Sigma, St. Louis, MO) with proteinase K and RNase treatment, according to the manufacturer\u0026rsquo;s instructions. Mitochondrial DNA copy number was estimated by comparing the abundance of the mitochondrial tRNA\u003csup\u003eLeu(UUR)\u003c/sup\u003e gene (determined by quantitative RT-PCR, forward primer: 5\u0026rsquo;-CACCCAAGAACAGGGTTTGT; reverse: 5\u0026rsquo;-TGGCCATGGGTATGTTGTTA) and with that of the nuclear \u0026beta;2-microglobulin gene (forward: 5\u0026rsquo;-TGCTGTCTCCATGTTTGATGTATCT; reverse: 5\u0026rsquo;-TCTCTGCTCCCCACCTCTAAGT).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eATP measurement:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eCellular ATP levels were measured with Luminescent ATP detection assay kit (Abcam) according to manufacturer\u0026rsquo;s protocol. The cells were cultured in the medium containing galactose instead of glucose and the readings were normalized to DNA abundance measured by Sybrsafe staining.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStatistical methods \u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eGroup descriptive statistics are presented as mean \u0026plusmn; SD and group count (percentage). The Kolmogorov-Smirnov test was used to test normality of the parameters (cord resistin, maternal Age, HbA1C, BMI, and gestational age). Among them, cord resistin, maternal age, and HbA1c were not normally distributed. Differences in characteristics between control and diabetic groups were assessed using Student\u0026rsquo;s t-test for normal distribution and nonparametric Mann-Whitney test for non-normal distribution. Maternal glucose (OGTT-2 hours) and maternal factors which displayed significant difference between control and diabetic groups, including maternal age, HbA1C, BMI, and gestational age, were subjected to correlation analysis with cord resistin. Spearman correlations were used for correlation analysis for non-normal distributions. Multiple regression analysis was conducted to further assess relationships after controlling multiple variables. In the multiple regression model, cord resistin was the dependent variable and study groups (control and diabetes), maternal age, BMI and gestational age were the independent variables. The statistical analysis were performed in Excel, GraphPad Prism, and SPSS. For all analysis, P-values \u0026lt;0.05 were treated as statistically significant.\u003c/p\u003e"},{"header":"Results:","content":"\u003cp\u003e\u003cstrong\u003eCord blood resistin concentration is increased in offspring born to mothers with diabetes during pregnancy and correlates with \u003c/strong\u003e\u003cstrong\u003ematernal blood glucose levels\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDemographics for participants providing cord blood samples are shown in Table 1. The participants with diabetes during pregnancy were older, had higher HBA1C, BMI, and slightly lower gestational age. There was no significant difference in the ethnicity and fetal sex between pregnant women with or without diabetes.\u003c/p\u003e\n\u003ctable width=\"100%\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eTable 1: Characteristics of Research Subjects Providing Cord Blood Samples\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\u003ctable width=\"623\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"2\" width=\"198\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"156\"\u003e\u003cbr /\u003e\n\u003cp\u003e\u003cstrong\u003eDM\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eN=42\u003c/p\u003e\n\u003cp\u003e(Male 21; Female 21)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"168\"\u003e\n\u003cp\u003e\u003cstrong\u003eControl\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eN=81\u003c/p\u003e\n\u003cp\u003e(Male 37; Female 44)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"102\"\u003e\n\u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e(DM vs Control)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"2\" width=\"198\"\u003e\n\u003cp\u003eMaternal Age, Y\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"156\"\u003e\n\u003cp\u003e31\u0026plusmn;5.9\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"168\"\u003e\n\u003cp\u003e24.47\u0026plusmn;4.4\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"102\"\u003e\n\u003cp\u003eP\u0026lt;0.001\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"2\" width=\"198\"\u003e\n\u003cp\u003eMaternal HbA1C, %\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"156\"\u003e\n\u003cp\u003e5.68\u0026plusmn;0.74\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"168\"\u003e\n\u003cp\u003e5.15\u0026plusmn;0.28\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"102\"\u003e\n\u003cp\u003eP\u0026lt;0.001\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"2\" width=\"198\"\u003e\n\u003cp\u003eMaternal BMI\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"156\"\u003e\n\u003cp\u003e32.74\u0026plusmn;6.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"168\"\u003e\n\u003cp\u003e28.22\u0026plusmn;6.77\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"102\"\u003e\n\u003cp\u003eP\u0026lt;0.01\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"2\" width=\"198\"\u003e\n\u003cp\u003eGestational age, weeks\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"156\"\u003e\n\u003cp\u003e38.89\u0026plusmn;0.66\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"168\"\u003e\n\u003cp\u003e39.55\u0026plusmn;0.95\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"102\"\u003e\n\u003cp\u003eP\u0026lt;0.001\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"66\"\u003e\n\u003cp\u003eRace\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003eNative American\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"156\"\u003e\n\u003cp\u003e24 (57%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"168\"\u003e\n\u003cp\u003e56 (69%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"102\"\u003e\n\u003cp\u003eP\u0026gt;0.05\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"66\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"132\"\u003e\n\u003cp\u003eHispanic\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"156\"\u003e\n\u003cp\u003e18 (43%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"168\"\u003e\n\u003cp\u003e25 (31%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"102\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe level of resistin in cord blood of infants born to mothers with diabetes (67.3 \u0026plusmn; 48.4 ng/ml, n=42) were significantly higher (P=0.03) than those born to control women (50.4 \u0026plusmn; 35.2 ng/ml, n=81) (Figure 1A). Cord blood resistin levels were significantly higher compared to the corresponding maternal blood resistin levels in control (Fig. 1B) and women with diabetes (Fig. 1C). Concentrations of human resistin in cord sera correlated significantly (R=0.4, P=0.002) with maternal glucose concentrations measured 2 hours after oral glucose challenge (OGTT, Fig. 2) during the second trimester of pregnancy. The correlation of cord blood resistin concentrations with maternal HbA1C at delivery was approaching significance (P=0.057), whereas there were no significant correlations between cord blood resistin with maternal age, BMI, or gestational age at\u003c/p\u003e\n\u003ctable width=\"100%\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eTable 2: Spearman tests on correlation of maternal factors with Cord blood Resistin levels\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr /\u003e birth (Table 2).\u003c/p\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"216\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"189\"\u003e\n\u003cp\u003eR (Correlation Coefficient with Cord resistin)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"219\"\u003e\n\u003cp\u003eCorrelation with Cord resistin\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"216\"\u003e\n\u003cp\u003eMaternal Age, Y\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"189\"\u003e\n\u003cp\u003e0.082\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"219\"\u003e\n\u003cp\u003eP\u0026gt;0.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"216\"\u003e\n\u003cp\u003eMaternal HbA1C, %\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"189\"\u003e\n\u003cp\u003e0.207\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"219\"\u003e\n\u003cp\u003eP=0.057\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"216\"\u003e\n\u003cp\u003eMaternal BMI\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"189\"\u003e\n\u003cp\u003e0.028\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"219\"\u003e\n\u003cp\u003eP\u0026gt;0.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"216\"\u003e\n\u003cp\u003eGestational age, weeks\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"189\"\u003e\n\u003cp\u003e0.059\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"219\"\u003e\n\u003cp\u003eP\u0026gt;0.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003ctable width=\"618\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"240\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"378\"\u003e\n\u003cp\u003eDependable Variable: human Cord resistin\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"240\"\u003e\n\u003cp\u003eVariable\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"198\"\u003e\n\u003cp\u003eStandardized Coefficients Beta\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"180\"\u003e\n\u003cp\u003eSignificance (P)\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"240\"\u003e\n\u003cp\u003eDiabetes During Pregnancy\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"198\"\u003e\n\u003cp\u003e0.279\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"180\"\u003e\n\u003cp\u003eP=0.03*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"240\"\u003e\n\u003cp\u003eMaternal Age\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"198\"\u003e\n\u003cp\u003e0.035\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"180\"\u003e\n\u003cp\u003eP\u0026gt;0.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"240\"\u003e\n\u003cp\u003eMaternal BMI\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"198\"\u003e\n\u003cp\u003e0.028\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"180\"\u003e\n\u003cp\u003eP\u0026gt;0.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"240\"\u003e\n\u003cp\u003eGestational age\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"198\"\u003e\n\u003cp\u003e0.059\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"180\"\u003e\n\u003cp\u003eP\u0026gt;0.1\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003ctable width=\"100%\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eTable3: Multiple regression analysis on the variables\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eMultiple regression analysis was conducted to further examine the relationship between fetal resistin and multiple variables. As shown in Table 3, only the presence of maternal diabetes reached significance in the regression model, indicating maternal age, BMI, and gestational age did not contribute to the different resistin levels between control and diabetic groups observed here.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSecretion of resistin from cord blood mononuclear cells in response to metabolic stresses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe expression of resistin mRNA in fetal tissues and cells was examined by quantitative real-time PCR. As shown in Figure 3A, resistin was highly expressed in cord blood mononuclear cells (CBMCs). Placenta also expressed resistin but at much lower abundance, whereas expression of resistin was not detectable in mesenchymal stem cells isolated from umbilical cord Wharton\u0026rsquo;s Jelly, nor in BeWo cells, a placental trophoblast cell line (Figure 3A). Treating CBMCs with high glucose, palmitate, or the inflammatory factor TNF\u0026alpha;, but not the oxidative stress inducer 4-HNE, resulted in increased levels of resistin in the culture media (Figure 3B).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHuman resistin inhibits placental \u003c/strong\u003e\u003cstrong\u003emitochondrial biogenesis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe previously reported a decrease in the PGC-1\u0026alpha;/TFAM mitochondrial biogenesis pathway in placenta of mothers with diabetes (23). Treating human placental explants with resistin resulted in a maximal decrease in PGC-1\u0026alpha; protein abundance at 100 ng/ml (Figure 4A) accompanied by a significant decrease in mitochondrial DNA copy number (Figure 4B), demonstrating the capacity of resistin to regulate placental mitochondrial biogenesis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHuman resistin decreases PGC-1\u0026alpha; and mitochondrial energy metabolism in placental trophoblasts\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTrophoblasts are the placental cells which provide the major source of nutrients for the growing embryos. In a transformed trophoblast cell line, BeWo cells, human resistin treatment also decreased the PGC-1\u0026alpha; protein abundance (Figure 5A) and its mRNA expression (Figure 5B). In addition, the protein level of pyruvate dehydrogenase (PDH) was decreased by resistin treatment (Figure 5A). Resistin also inhibited cellular ATP production (Figure 5D), further demonstrating the influence of resistin on mitochondrial energy metabolism.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion:","content":"\u003cp\u003eAn adverse maternal environment, such as diabetes during pregnancy, impacts fetal and placental development, which is associated with increased risk of metabolic diseases in offspring later in life (1-4). The present study demonstrates that an increase in cord blood resistin found in the presence of maternal diabetes may play a role in placental mitochondrial biogenesis and function.\u003c/p\u003e\n\u003cp\u003eA recent meta-analysis of 18 published studies (17) notes that resistin levels are elevated in maternal circulation in gestational diabetes. Much less is known about the determinants of resistin abundance in the fetal circulation and current reports regarding the association between cord blood resistin with diabetes during pregnancy are discordant (20-22). The present study found an increase in cord blood resistin in maternal diabetes, which agrees with the reports by Shang et al and Oncul et al (20, 21). We also demonstrated that resistin expression was highly enriched in cord blood mononuclear cells, suggesting that fetal mononuclear cells may be the main source of fetal circulating resistin. We, along with others (16, 28), detect expression of resistin in the placenta. \u0026nbsp;However, we found much lower abundance there compared to that in mononuclear cells. As no expression was detected in the placental trophoblast cell line, BeWo, we suspect that placental macrophages, rather than trophoblasts, are responsible for placental resistin expression.\u003c/p\u003e\n\u003cp\u003eIn addition to cord blood resistin concentration being higher in pregnancies complicated by diabetes, a positive correlation with maternal blood glucose levels was found. Hyperglycemia and hyperinsulinemia in GDM are known to activate inflammatory cells and induce a pro-inflammatory status (29). In accord, we found that cord blood mononuclear cells secreted resistin in response to exposure to high glucose and other diabetes-related factors. Thus, our findings further characterize resistin as an inflammatory cell-derived factor that responds to hyperglycemia and metabolic stresses associated with diabetic pregnancy. Our study begins to examine potential functions of resistin in the fetus, suggesting involvement in regulation of placental mitochondrial abundance and function. Mitochondria play a key role in placental function, and defects in placental mitochondrial function and content are associated with impaired placental energetics and increased oxidative stress, which lead to adverse pregnancy outcomes (30-32). We previously demonstrated a decrease in PGC-1\u0026alpha;/TFAM/mitochondrial biogenesis signaling in placenta of women with diabetes during pregnancy (23). Here we observed decreases in PGC-1\u0026alpha; expression and mitochondrial DNA copy number when human placental explants were exposed to resistin. In addition, resistin treatment reduced the abundance of pyruvate dehydrogenase (PDH) and ATP production. Pyruvate dehydrogenase is a mitochondrial enzyme that catalyzes pyruvate oxidation, linking glycolysis to the Krebs cycle for ATP generation to meet energy demands (33). Mitochondria\u0026nbsp;are the primary source of ATP needed for\u0026nbsp;placental\u0026nbsp;growth, nutrient transport, and hormone synthesis.\u0026nbsp; Therefore, increased expression of resistin may contribute to impaired placental mitochondrial biogenesis and function, as well as offspring adverse outcomes in pregnancies complicated by diabetes.\u003c/p\u003e\n\u003cp\u003eThe strengths of the present study are identification of resistin as a fetal factor derived from inflammatory cells that is affected by maternal diabetes and demonstration of a role for resistin in inhibiting placental mitochondrial metabolism. Limitations of the present study are that the specific downstream signaling underlying resistin effects on mitochondrial biogenesis and the roles of resistin on other fetal tissues remain to be explored. Four distinct receptors have been identified to bind to resistin, including Toll-like receptor 4 (TLR4), decorin, receptor tyrosine kinase-like orphan receptor 1 (ROR1), and adenylyl cyclase-associated protein 1 (CAP1) (34-36). \u0026nbsp;Resistin/TLR4 has been shown to inhibit AMP activated kinase (AMPK)(35, 37), an important regulator of mitochondrial biogenesis(37). TLR4 and AMPK inhibition can be the potential mechanism underlying resistin-induced decrease in placental mitochondrial metabolism. However, which of these receptors and the specific downstream pathways responsible for the effects of resistin on mitochondrial metabolism remains to be investigated. In addition, elevated fetal resistin can potentially impact energy metabolism and development of other fetal tissues, such as muscle, which remain to be studied.\u003c/p\u003e"},{"header":"Conclusions:","content":"\u003cp\u003eHere we provide evidence that resistin acts as a circulating factor linking inflammation and energy metabolism during fetal life and that it may contribute to impaired placental mitochondrial metabolism in maternal diabetes. \u0026nbsp;As much remains to be learned about the role of resistin during fetal life, the clinical implications of these findings await future studies and definition. However, maternal diabetes has both immediate and long-term effects on the offspring which are tied to energy management and mitochondrial function. Thus, human resistin could be a potential therapeutic target or a diagnostic marker for the short-term and long-term adverse pregnancy outcomes of diabetes during pregnancy.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003ecord blood mononuclear cells (CBMCs); peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1\u0026alpha;); gestational diabetes (GDM); 4-Hydroxynonenal (4-HNE); pyruvate dehydrogenase (PDH).\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe studies on human cord serum samples (IRB protocol#1267), and the CBMCs and placental explants (IRB #2540) were approved by the Institutional Review Boards of the University of Oklahoma Health Science Center, the Chickasaw Nation, and the Choctaw Nation of Oklahoma.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; All authors contributed to the conception, design and interpretation of the data. SJ, AMT, and JBT performed the experiments. SJ and SDC wrote the manuscript. All authors revised the manuscript and approved this version to be published.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements and funding:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank study coordinators Mary Ayn Tullier, Justin Fowler, Olufolake Olufowote and Shelly Hopper; the Choctaw Nation of Oklahoma and the Chickasaw Nation; and our study participants and families. This study was supported by NIH Grants R01 DK089034-05 (S. Chernausek, PI), P20 MD000528-05 (T. Lyons, Project PI), and NIH K23 award (PI: J. Tryggestad-K23DK106533); American Diabetes Association Grant 1-10-CT-09 (S. Chernausek, PI); the OCAST (S. Jiang); and OK-INBRE Grant (RPI: S. Jiang).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclarations:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere is no conflict of interest associated with this manuscript. The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eFetita LS, Sobngwi E, Serradas P, Calvo F, Gautier JF. (2006) Consequences of fetal exposure to maternal diabetes in offspring. \u003cem\u003eJ Clin Endocrinol Metab\u003c/em\u003e \u003cstrong\u003e91:\u003c/strong\u003e 3718-3724.\u003c/li\u003e\n\u003cli\u003eDabelea D, Crume T. (2011) Maternal environment and the transgenerational cycle of obesity and diabetes. \u003cem\u003eDiabetes\u003c/em\u003e \u003cstrong\u003e60:\u003c/strong\u003e 1849-1855.\u003c/li\u003e\n\u003cli\u003eDamm P\u003cem\u003e, et al.\u003c/em\u003e (2016) Gestational diabetes mellitus and long-term consequences for mother and offspring: a view from Denmark. \u003cem\u003eDiabetologia\u003c/em\u003e \u003cstrong\u003e59:\u003c/strong\u003e 1396-1399.\u003c/li\u003e\n\u003cli\u003eFriedman JE. (2018) Developmental Programming of Obesity and Diabetes in Mouse, Monkey, and Man in 2018: Where Are We Headed? \u003cem\u003eDiabetes\u003c/em\u003e \u003cstrong\u003e67:\u003c/strong\u003e 2137-2151.\u003c/li\u003e\n\u003cli\u003eJarmuzek P, Wielgos M, Bomba-Opon D. (2015) Placental pathologic changes in gestational diabetes mellitus. \u003cem\u003eNeuro Endocrinol Lett\u003c/em\u003e \u003cstrong\u003e36:\u003c/strong\u003e 101-105.\u003c/li\u003e\n\u003cli\u003eOsmond DT, Nolan CJ, King RG, Brennecke SP, Gude NM. (2000) Effects of gestational diabetes on human placental glucose uptake, transfer, and utilisation. \u003cem\u003eDiabetologia\u003c/em\u003e \u003cstrong\u003e43:\u003c/strong\u003e 576-582.\u003c/li\u003e\n\u003cli\u003eMuralimanoharan S, Maloyan A, Myatt L. (2016) Mitochondrial function and glucose metabolism in the placenta with gestational diabetes mellitus: role of miR-143. \u003cem\u003eClin Sci (Lond)\u003c/em\u003e \u003cstrong\u003e130:\u003c/strong\u003e 931-941.\u003c/li\u003e\n\u003cli\u003eDesoye G, Hauguel-de Mouzon S. (2007) The human placenta in gestational diabetes mellitus. The insulin and cytokine network. \u003cem\u003eDiabetes Care\u003c/em\u003e \u003cstrong\u003e30 Suppl 2:\u003c/strong\u003e S120-126.\u003c/li\u003e\n\u003cli\u003eSteppan CM\u003cem\u003e, et al.\u003c/em\u003e (2001) The hormone resistin links obesity to diabetes. \u003cem\u003eNature\u003c/em\u003e \u003cstrong\u003e409:\u003c/strong\u003e 307-312.\u003c/li\u003e\n\u003cli\u003eGhosh S, Singh AK, Aruna B, Mukhopadhyay S, Ehtesham NZ. (2003) The genomic organization of mouse resistin reveals major differences from the human resistin: functional implications. \u003cem\u003eGene\u003c/em\u003e \u003cstrong\u003e305:\u003c/strong\u003e 27-34.\u003c/li\u003e\n\u003cli\u003eSchwartz DR, Lazar MA. (2011) Human resistin: found in translation from mouse to man. \u003cem\u003eTrends Endocrinol Metab\u003c/em\u003e \u003cstrong\u003e22:\u003c/strong\u003e 259-265.\u003c/li\u003e\n\u003cli\u003eLazar MA. (2007) Resistin- and Obesity-associated metabolic diseases. \u003cem\u003eHorm Metab Res\u003c/em\u003e \u003cstrong\u003e39:\u003c/strong\u003e 710-716.\u003c/li\u003e\n\u003cli\u003eMcTernan CL\u003cem\u003e, et al.\u003c/em\u003e (2002) Resistin, central obesity, and type 2 diabetes. \u003cem\u003eLancet\u003c/em\u003e \u003cstrong\u003e359:\u003c/strong\u003e 46-47.\u003c/li\u003e\n\u003cli\u003eGerber M\u003cem\u003e, et al.\u003c/em\u003e (2005) Serum resistin levels of obese and lean children and adolescents: biochemical analysis and clinical relevance. \u003cem\u003eJ Clin Endocrinol Metab\u003c/em\u003e \u003cstrong\u003e90:\u003c/strong\u003e 4503-4509.\u003c/li\u003e\n\u003cli\u003ePfutzner A, Langenfeld M, Kunt T, Lobig M, Forst T. (2003) Evaluation of human resistin assays with serum from patients with type 2 diabetes and different degrees of insulin resistance. \u003cem\u003eClin Lab\u003c/em\u003e \u003cstrong\u003e49:\u003c/strong\u003e 571-576.\u003c/li\u003e\n\u003cli\u003eChen D\u003cem\u003e, et al.\u003c/em\u003e (2005) Alterations of serum resistin in normal pregnancy and pre-eclampsia. \u003cem\u003eClin Sci (Lond)\u003c/em\u003e \u003cstrong\u003e108:\u003c/strong\u003e 81-84.\u003c/li\u003e\n\u003cli\u003eHu SM, Chen MS, Tan HZ. (2019) Maternal serum level of resistin is associated with risk for gestational diabetes mellitus: A meta-analysis. \u003cem\u003eWorld J Clin Cases\u003c/em\u003e \u003cstrong\u003e7:\u003c/strong\u003e 585-599.\u003c/li\u003e\n\u003cli\u003eBellos I, Fitrou G, Pergialiotis V, Perrea DN, Daskalakis G. (2019) Serum levels of adipokines in gestational diabetes: a systematic review. \u003cem\u003eJ Endocrinol Invest\u003c/em\u003e \u003cstrong\u003e42:\u003c/strong\u003e 621-631.\u003c/li\u003e\n\u003cli\u003eBao W\u003cem\u003e, et al.\u003c/em\u003e (2015) Adipokine levels during the first or early second trimester of pregnancy and subsequent risk of gestational diabetes mellitus: A systematic review. \u003cem\u003eMetabolism\u003c/em\u003e \u003cstrong\u003e64:\u003c/strong\u003e 756-764.\u003c/li\u003e\n\u003cli\u003eShang M, Dong X, Hou L. (2018) Correlation of adipokines and markers of oxidative stress in women with gestational diabetes mellitus and their newborns. \u003cem\u003eJ Obstet Gynaecol Res\u003c/em\u003e \u003cstrong\u003e44:\u003c/strong\u003e 637-646.\u003c/li\u003e\n\u003cli\u003eOncul M\u003cem\u003e, et al.\u003c/em\u003e (2013) Maternal and cord blood apelin, resistin and visfatin levels in gestational diabetes mellitus. \u003cem\u003eMinerva Med\u003c/em\u003e \u003cstrong\u003e104:\u003c/strong\u003e 527-535.\u003c/li\u003e\n\u003cli\u003eMohamed MH\u003cem\u003e, et al.\u003c/em\u003e (2010) Cord blood resistin and adiponectin in term newborns of diabetic mothers. \u003cem\u003eArch Med Sci\u003c/em\u003e \u003cstrong\u003e6:\u003c/strong\u003e 558-566.\u003c/li\u003e\n\u003cli\u003eJiang S\u003cem\u003e, et al.\u003c/em\u003e (2017) Effects of maternal diabetes and fetal sex on human placenta mitochondrial biogenesis. \u003cem\u003ePlacenta\u003c/em\u003e \u003cstrong\u003e57:\u003c/strong\u003e 26-32.\u003c/li\u003e\n\u003cli\u003eTeague AM\u003cem\u003e, et al.\u003c/em\u003e (2015) Cord blood adipokines, neonatal anthropometrics and postnatal growth in offspring of Hispanic and Native American women with diabetes mellitus. \u003cem\u003eReprod Biol Endocrinol\u003c/em\u003e \u003cstrong\u003e13:\u003c/strong\u003e 68.\u003c/li\u003e\n\u003cli\u003eAmerican Diabetes A. (2003) Gestational diabetes mellitus. \u003cem\u003eDiabetes Care\u003c/em\u003e \u003cstrong\u003e26 Suppl 1:\u003c/strong\u003e S103-105.\u003c/li\u003e\n\u003cli\u003eShaoning Jiang AMT, Jeanie B. Tryggestad, Mary E. Jensen, and Steven D. Chernausek. (2020) Role of metformin in epigenetic regulation of placental mitochondrial biogenesis in maternal diabetes. In: \u003cem\u003eScientific Reports.\u003c/em\u003e\u003c/li\u003e\n\u003cli\u003eBoyle KE\u003cem\u003e, et al.\u003c/em\u003e (2016) Mesenchymal Stem Cells From Infants Born to Obese Mothers Exhibit Greater Potential for Adipogenesis: The Healthy Start BabyBUMP Project. \u003cem\u003eDiabetes\u003c/em\u003e \u003cstrong\u003e65:\u003c/strong\u003e 647-659.\u003c/li\u003e\n\u003cli\u003eErol O\u003cem\u003e, et al.\u003c/em\u003e (2016) Serum level and placental expression of resistin in pregnancies complicated by preeclampsia: relationship with disease severity. \u003cem\u003eClin Exp Obstet Gynecol\u003c/em\u003e \u003cstrong\u003e43:\u003c/strong\u003e 516-521.\u003c/li\u003e\n\u003cli\u003ePantham P, Aye IL, Powell TL. (2015) Inflammation in maternal obesity and gestational diabetes mellitus. \u003cem\u003ePlacenta\u003c/em\u003e \u003cstrong\u003e36:\u003c/strong\u003e 709-715.\u003c/li\u003e\n\u003cli\u003eMando C\u003cem\u003e, et al.\u003c/em\u003e (2018) Impact of Obesity and Hyperglycemia on Placental Mitochondria. \u003cem\u003eOxid Med Cell Longev\u003c/em\u003e \u003cstrong\u003e2018:\u003c/strong\u003e 2378189.\u003c/li\u003e\n\u003cli\u003eClemente DBP\u003cem\u003e, et al.\u003c/em\u003e (2017) Prenatal ambient air pollution exposure, infant growth and placental mitochondrial DNA content in the INMA birth cohort. \u003cem\u003eEnviron Res\u003c/em\u003e \u003cstrong\u003e157:\u003c/strong\u003e 96-102.\u003c/li\u003e\n\u003cli\u003eBijnens EM\u003cem\u003e, et al.\u003c/em\u003e (2019) Placental mitochondrial DNA content is associated with childhood intelligence. \u003cem\u003eJ Transl Med\u003c/em\u003e \u003cstrong\u003e17:\u003c/strong\u003e 361.\u003c/li\u003e\n\u003cli\u003ePark S\u003cem\u003e, et al.\u003c/em\u003e (2018) Role of the Pyruvate Dehydrogenase Complex in Metabolic Remodeling: Differential Pyruvate Dehydrogenase Complex Functions in Metabolism. \u003cem\u003eDiabetes Metab J\u003c/em\u003e \u003cstrong\u003e42:\u003c/strong\u003e 270-281.\u003c/li\u003e\n\u003cli\u003eZhao CW\u003cem\u003e, et al.\u003c/em\u003e (2019) An Update on the Emerging Role of Resistin on the Pathogenesis of Osteoarthritis. \u003cem\u003eMediators Inflamm\u003c/em\u003e \u003cstrong\u003e2019:\u003c/strong\u003e 1532164.\u003c/li\u003e\n\u003cli\u003eMiao J\u003cem\u003e, et al.\u003c/em\u003e (2018) Resistin inhibits neuronal autophagy through Toll-like receptor 4. \u003cem\u003eJ Endocrinol\u003c/em\u003e \u003cstrong\u003e238:\u003c/strong\u003e 77-89.\u003c/li\u003e\n\u003cli\u003eLee S\u003cem\u003e, et al.\u003c/em\u003e (2014) Adenylyl cyclase-associated protein 1 is a receptor for human resistin and mediates inflammatory actions of human monocytes. \u003cem\u003eCell Metab\u003c/em\u003e \u003cstrong\u003e19:\u003c/strong\u003e 484-497.\u003c/li\u003e\n\u003cli\u003eHardie DG. (2007) AMP-activated/SNF1 protein kinases: conserved guardians of cellular energy. \u003cem\u003eNat Rev Mol Cell Biol\u003c/em\u003e \u003cstrong\u003e8:\u003c/strong\u003e 774-785.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cbr /\u003e \u0026nbsp;\u003c/strong\u003e\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":"molecular-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mome","sideBox":"Learn more about [Molecular Medicine](https://molmed.biomedcentral.com)","snPcode":"10020","submissionUrl":"https://submission.springernature.com/new-submission/10020/3","title":"Molecular Medicine","twitterHandle":"@MolecularMedic1","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"human resistin, diabetes during pregnancy, placenta, mitochondria","lastPublishedDoi":"10.21203/rs.3.rs-19051/v2","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-19051/v2","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Diabetes during pregnancy affects placental mitochondrial content and function, which has the potential to impact fetal development and the long-term health of offspring. Resistin is a peptide hormone originally discovered in mice as an adipocyte-derived factor that induced insulin resistance. In humans, resistin is primarily secreted by monocytes or macrophages. The regulation and roles of human resistin in diabetes during pregnancy remain unclear. \u0026nbsp;\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Fetal resistin levels were measured in cord blood from pregnancies with (n=42) and without maternal diabetes (n=81). Secretion of resistin from cord blood mononuclear cells (CBMCs) was measured. The actions of human resistin in mitochondrial biogenesis were determined in placental trophoblastic cells (BeWo cells) or human placental explant.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Concentrations of human resistin in cord sera were higher in diabetic pregnancies (67 ng/ml) compared to healthy controls (50 ng/ml, P\u0026lt; 0.05), and correlated (r=0.4, P=0.002) with a measure of maternal glycemia (glucose concentration 2 h post challenge). Resistin mRNA was most abundant in cord blood mononuclear cells (CBMCs) compared with placenta and mesenchymal stem cells (MSCs). Secretion of resistin from cultured CBMCs was increased in response to high glucose (25 mM). Exposing BeWo cells or human placental explant to resistin decreased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), mitochondrial abundance, and ATP production. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e Resistin is increased in fetal circulation of infants exposed to the diabetic milieu, potentially reflecting a response of monocytes/macrophages to hyperglycemia and metabolic stresses associated with diabetes during pregnancy. Increased exposure to resistin may contribute to mitochondrial dysfunction and aberrant energy metabolism characteristic of offspring exposed to diabetes \u003cem\u003ein utero\u003c/em\u003e.\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","manuscriptTitle":"Fetal circulating human resistin increases in diabetes during pregnancy and impairs placental mitochondrial biogenesis","msid":"","msnumber":"","nonDraftVersions":[{"code":2,"date":"2020-06-17 20:49:22","doi":"10.21203/rs.3.rs-19051/v2","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorAssigned","content":"","date":"2020-06-16T12:00:00+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2020-06-15T12:00:00+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2020-06-15T12:00:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"molecular-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mome","sideBox":"Learn more about [Molecular Medicine](https://molmed.biomedcentral.com)","snPcode":"10020","submissionUrl":"https://submission.springernature.com/new-submission/10020/3","title":"Molecular Medicine","twitterHandle":"@MolecularMedic1","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}},{"code":1,"date":"2020-03-27 15:03:39","doi":"10.21203/rs.3.rs-19051/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2020-04-27T12:00:00+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2020-04-26T12:00:00+00:00","index":3,"fulltext":"Recommendation: Reviewer's comments unavailable due to the journal's policy.\n"},{"type":"reviewerAgreed","content":"","date":"2020-04-14T12:00:00+00:00","index":3,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2020-04-05T12:00:00+00:00","index":1,"fulltext":"Recommendation: Reviewer's comments unavailable due to the journal's policy.\n"},{"type":"editorInvitedReview","content":"","date":"2020-04-05T12:00:00+00:00","index":2,"fulltext":"Recommendation: Reviewer's comments unavailable due to the journal's policy.\n"},{"type":"reviewerAgreed","content":"","date":"2020-04-01T12:00:00+00:00","index":1,"fulltext":""},{"type":"reviewerAgreed","content":"","date":"2020-04-01T12:00:00+00:00","index":2,"fulltext":""},{"type":"editorAssigned","content":"","date":"2020-03-30T12:00:00+00:00","index":"","fulltext":""},{"type":"reviewersInvited","content":"","date":"2020-03-30T12:00:00+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2020-03-29T12:00:00+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2020-03-25T12:00:00+00:00","index":"","fulltext":""},{"type":"submitted","content":"","date":"2020-03-22T12:00:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"molecular-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mome","sideBox":"Learn more about [Molecular Medicine](https://molmed.biomedcentral.com)","snPcode":"10020","submissionUrl":"https://submission.springernature.com/new-submission/10020/3","title":"Molecular Medicine","twitterHandle":"@MolecularMedic1","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"c2746c3a-efe9-4e90-9729-56cd4cc9c588","owner":[],"postedDate":"June 17th, 2020","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":75640,"name":"Molecular Epidemiology"},{"id":75641,"name":"Maternal \u0026 Fetal Medicine"}],"tags":[],"updatedAt":"2020-08-09T15:01:36+00:00","versionOfRecord":{"articleIdentity":"rs-19051","link":"https://doi.org/10.1186/s10020-020-00205-y","journal":{"identity":"molecular-medicine","isVorOnly":false,"title":"Molecular Medicine"},"publishedOn":"2020-08-06 12:00:00","publishedOnDateReadable":"August 6th, 2020"},"versionCreatedAt":"2020-06-17 20:49:22","video":"","vorDoi":"10.1186/s10020-020-00205-y","vorDoiUrl":"https://doi.org/10.1186/s10020-020-00205-y","workflowStages":[]},"version":"v2","identity":"rs-19051","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-19051","identity":"rs-19051","version":["v2"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}

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