Mouse Model Of Gestational Diabetes Mellitus Research Articles

Chemerin alleviates the placental oxidative stress and improves fetal overgrowth of gestational diabetes mellitus mice induced by high fat diet

BackgroundEvidence has shown that oxidative stress induced by high glucose microenvironment in placenta of gestational diabetes mellitus (GDM) is indispensable to the progression of this condition. Adipokine chemerin was linked with GDM, yet the roles of chemerin in placental oxidative stress and its underlying effects on GDM in vivo remain elusive.MethodsWe firstly analyzed the disparities of oxidative stress levels in placenta between GDM and normoglycaemic pregnant women, and then added recombinant active chemerin to the high-glucose treated human trophoblastic cells to investigate effects of chemerin on reactive oxygen species (ROS), total antioxidant capacity (T-AOC) and intake of glucose. Finally, a GDM animal model induced by high-fat diet (HFD) was established and the impacts of chemerin on oxidative stress of placenta and fetal growth of GDM were explored.ResultsAnalysis of human samples showed that the extent of lipid peroxidation in placenta was significantly elevated in GDM patients compared with their normoglycaemic counterparts. In the high glucose cell model, active chemerin lessened the content of ROS, heightened the index of T-AOC and stimulated glucose uptake in a concentration-dependent manner. Importantly, we successfully constructed a GDM mouse model through HFD. The treatment of chemerin was found to alleviate the high blood glucose levels in these HFD-fed pregnant mice and attenuate the excessive growth of their offspring. Our data also revealed that chemerin might counteract placental oxidative stress in HFD mice by improving the activity of superoxide dismutase.ConclusionsThe present study further elucidated the molecular biology of chemerin, which plays a pivotal role in ameliorating oxidative stress and hyperglycemia, resulting in improved fetal overgrowth in GDM.Graphical abstract

Circ-ADAM9 Knockdown Reduces Insulin Resistance and Placental Injury in Diabetic Mice via MAPK Pathway Inactivation.

Gestational diabetes mellitus (GDM) significantly risks maternal and neonatal health. Circular RNAs (circRNAs) regulate various diseases but their role in GDM is unclear. We investigated the involvement of circ-ADAM9 in GDM. We analyzed circ-ADAM9 expression in GDM-related microarray data (GSE182737) and measured its levels in the blood of GDM patients. In a high-fat diet-induced GDM mouse model, we inhibited circ-ADAM9 expression and tracked blood glucose levels, serum insulin, lipid levels, placental apoptosis, and reactive oxygen species (ROS) levels. Pathological changes in pancreatic tissues and fetal outcomes were also examined. Molecular interactions were explored using bioinformatics tools and validated through luciferase assays, real-time quantitative polymerase chain reaction (RT-qPCR), and Western blotting in high glucose (HG)-induced human trophoblast cells (HTR-8/SVneo). We further investigated the involvement of circ-ADAM9/miR-375/FPR2 axis in HG-induced injury in HTR-8/SVneo cells by assessing cell viability, apoptosis, ROS production, and antioxidant levels. Both GDM patients and GDM-induced mice exhibited a substantial upregulation of circ-ADAM9. Knockdown of circ-ADAM9 lowered blood glucose, alleviated insulin resistance, improved lipid metabolism, decreased placental apoptosis and ROS levels, and reduced pancreatic lesions in GDM mice. Circ-ADAM9 downregulation also improved fetal viability, weight, and crown-rump length. In HG-induced HTR-8/SVneo cells, circ-ADAM9 overexpression and miR-375 downregulation were evident. Overexpression of miR-375 inhibited circ-ADAM9 activity, substantiating their binding interaction. In GDM mice, circ-ADAM9 deficiency restored miR-375 expression. TargetScanHuman predicted and luciferase assays confirmed the miR-375-FPR2 interaction and elevated FPR2 levels in GDM mice were reduced by circ-ADAM9 silencing. In HG-induced HTR-8/SVneo cells, circ-ADAM9 knockdown restored cell viability, suppressed apoptosis and ROS levels, and enhanced antioxidant enzyme levels. These effects were reversed by miR-375 inhibition or FPR2 overexpression, suggesting circ-ADAM9 upregulates FPR2 expression by sponging miR-375 and modulating the MAPK pathway. This study is the first to demonstrate the expression and function of circ-ADAM9 in the progression of GDM. Circ-ADAM9 downregulation ameliorates insulin resistance and placental injury in GDM by modulating the miR-375/FPR2 axis and inactivating the MAPK pathway, which may offer a novel therapeutic target for the treatment of GDM.

Gestational diabetes exacerbates intrauterine microbial exposure induced intestinal microbiota change in offspring contributing to increased immune response.

maternal health during pregnancy can affect the intestinal microbial community of offspring, but currently the impact of intrauterine environmental changes resulting from gestational diabetes mellitus (GDM) on the microbiota of offspring as well as its interaction with the immune system remains unclear. to explore the impact of intrauterine microbial exposure during pregnancy of gestational diabetes mellitus on the development of neonate's intestinal microbiota and activation of immune responses. Levels of lipopolysaccharides in cord blood from GDM and expression of microbial recognition-related proteins in the placenta were measured. To evaluate embryonic intestinal colonization, pregnant mice with GDM were administered with labeled Escherichia coli or Lactobacillus. The intestinal colonization of pups was analyzed through 16S rRNA gene sequencing and labeled microbial culture. Additionally, memory T lymphocyte and dendritic cell co-culture experiments were conducted to elucidate the immune memory of intestinal microbes during the embryonic stages. Gestational diabetes mellitus led to elevated umbilical cord blood LPS level and increased GFP labeled Escherichia coli in the offspring's intestine after gestational microbial exposure. The mouse model of GDM exhibited increased immune markers including TLR4, TLR5, IL-22 and IL-23 in the placenta and a recall response from memory T cells in offspring's intestines, with similar observations found in human experiments. Furthermore, reduced intestinal microbiome diversity and an increased ratio of Firmicutes/Bacteroidetes was found in GDM progeny, with the stability of bacterial colonization been interfered. Our investigation has revealed a noteworthy correlation between gestational diabetes and intrauterine microbial exposure, as well as alterations in the neonatal microbiota and activation of immune responses. These findings highlight the gestational diabetes's role on offspring's gut microbiota and immune system interactions with early-life pathogen exposure.

In vitro and in vivo effects of Galectin-3 inhibitor TD139 on inflammation and ERK/JNK/p38 pathway in gestational diabetes mellitus.

This study aims to investigate the effects of the Galectin-3 (Gal-3) inhibitor TD139 on inflammation and the extracellular signal-regulated kinase (ERK)/c-Jun N-terminal kinase (JNK)/p38 pathway in gestational diabetes mellitus (GDM). Human placental tissues were treated with TD139 and TNF-α, assessing Gal-3, ERK/JNK/p38 activation, and inflammatory cytokines. GDM was induced in mice via subcutaneous injections of streptozotocin (STZ). After confirming GDM, mice were treated with 15 mg/kg TD139 on GD 10.5 12.5, 14.5, 16.5, and 18.5. Serum inflammatory cytokines were measured on GD 20.5, and post-delivery placental tissues were analyzed. Data were analyzed using one-way or two-way repeated measures ANOVA with post hoc tests. TD139 suppressed TNF-α-induced increases in Gal-3, IL-1β, IL-6, MCP-1, and ERK/JNK/p38 activation in placental tissues. In STZ-induced GDM mice, TD139 reduced glucose levels, weight loss, and food and water intake. TD139 significantly lowered TNF-α, IL-1β, IL-6, and MCP-1 in serum and placental tissues and inhibited the ERK/JNK/p38 pathway. TD139 improved pup numbers in GDM mice compared to untreated ones. TD139 reduces inflammation and inhibits the ERK/JNK/p38 pathway in TNF-α stimulated placental tissues and STZ-induced GDM mice, suggesting its therapeutic potential for managing GDM-related placental inflammation and improving pregnancy outcomes. The study used TNF-α to mimic GDM in placental tissues and an STZ-induced GDM mouse model, which may not fully represent human GDM complexity. Future research should explore alternative models, and broader signaling pathways, and thoroughly evaluate TD139's safety in pregnancy.

Postpartum development of metabolic dysfunction-associated steatotic liver disease in a lean mouse model of gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is associated with increased postpartum risk for metabolic dysfunction-associated steatotic liver disease (MASLD). GDM-related MASLD predisposes to advanced liver disease, necessitating a better understanding of its development in GDM. This preclinical study evaluated the MASLD development in a lean GDM mouse model with impaired insulin secretion capacity. Lean GDM was induced by short-term 60% high-fat diet and low-dose streptozotocin injections (60 mg/kg for 3 days) before mating in C57BL/6N mice. The control dams received only high-fat diet or low-fat diet. Glucose homeostasis was assessed during pregnancy and postpartum, whereas MASLD was assessed on postpartum day 30 (PP30). GDM dams exhibited a transient hyperglycemic phenotype during pregnancy, with hyperglycaemia reappearing after lactation. Lower insulin levels and impaired glucose-induced insulin response were observed in GDM mice during pregnancy and postpartum. At PP30, GDM dams displayed higher hepatic triglyceride content compared controls, along with increased MAS (MASLD) activity scores, indicating lipid accumulation, inflammation, and cell turnover indices. Additionally, at PP30, GDM dams showed elevated plasma liver injury markers. Given the absence of obesity in this double-hit GDM model, the results clearly indicate that impaired insulin secretion driven pregnancy hyperglycaemia has a distinct contribution to the development of postpartum MASLD.

Gestational diabetes mellitus induces congenital anomalies of the kidney and urinary tract in mice by altering RET/MAPK/ERK pathway

Gestational diabetes mellitus (GDM) presents a substantial population health concern. Previous studies have revealed that GDM can ultimately influence nephron endowment. In this study, we established a GDM mouse model to investigate the embryological alterations and molecular mechanisms underlying the development of congenital anomalies of the kidney and urinary tract (CAKUT) affected by GDM. Our study highlights that GDM could contribute to the manifestation of CAKUT, with prevalent phenotypes characterized by isolated hydronephrosis and duplex kidney complicated with hydronephrosis in mice. Ectopic ureteric buds (UBs) and extended length of common nephric ducts (CNDs) were noted in the metanephric development stage. The expression of Ret and downstream p-ERK activity were enhanced in UBs, which indicated the alteration of RET/MAPK/ERK pathway may be one of the mechanisms contributing to the increased occurrence of CAKUT associated with GDM.

Lachnospiraceae-derived butyrate mediates protection of high fermentable fiber against placental inflammation in gestational diabetes mellitus.

Inflammation-associated insulin resistance is a key trigger of gestational diabetes mellitus (GDM), but the underlying mechanisms and effective interventions remain unclear. Here, we report the association of placental inflammation (tumor necrosis factor-α) and abnormal maternal glucose metabolism in patients with GDM, and a high fermentable dietary fiber (HFDF; konjac) could reduce GDM development through gut flora-short-chain fatty acid-placental inflammation axis in GDM mouse model. Mechanistically, HFDF increases abundances of Lachnospiraceae and butyrate, reduces placental-derived inflammation by enhancing gut barrier and inhibiting the transfer of bacterial-derived lipopolysaccharide, and ultimately resists high-fat diet-induced insulin resistance. Lachnospiraceae and butyrate have similar anti-GDM and anti-placental inflammation effects, and they can ameliorate placental function and pregnancy outcome effects probably by dampening placental immune dysfunction. These findings demonstrate the involvement of important placental inflammation-related mechanisms in the progression of GDM and the great potential of HFDFs to reduce susceptibility to GDM through gut-flora-placenta axis.

Periostin acts as a bridge between gestational diabetes mellitus (GDM) and chronic inflammation to modulate insulin resistance by modulating PPARα/NF-κB/TNF-α signaling pathway.

Gestational diabetes mellitus (GDM) is considered an imbalance of glucose metabolism and insulin resistance during pregnancy. To evaluate the levels of periostin (POSTN) in patients with GDM and investigate the association between POSTN and GDM. A total of 30 pregnant women (NC group) and 30 pregnant women with GDM (GDM group) were involved. The GDM mouse model was established by intraperitoneally injecting streptozotocin. The oral glucose tolerance test (OGTT), insulin, and insulin resistance indices were tested. An immunohistochemical and Western blot assay was conducted to determine the expression of POSTN, PPARα, TNF-α, and NF-kB. HE staining was performed to evaluate inflammation in the placental tissues of women with GDM and GDM mice. POSTN-siRNA was transfected into glucose-pretreated HTR8 cells, and pAdEasy-m-POSTN shRNA was infected in GDM mice. The RT-PCR assay determined the gene transcription of POSTN, TNF-α, NF-kB, and PPARα. Pregnant women in the GDM group demonstrated significantly higher OGTT (p<0.05), insulin levels (p<0.05) and insulin resistance (p<0.05) compared to those of the NC group. The serum levels of POSTN in pregnant women of the GDM group were significantly higher than that of the NC group (p<0.05). The obvious inflammation was activated in pregnant women in the GDM group. POSTN-siRNA significantly enhanced the cell viability of glucose-treated HTR8 cells compared to that without glucose treatment (p<0.05). POSTN-siRNA (pAdEasy-m-POSTN shRNA) markedly reduced the glucose level of glucose-treated HTR8 cells (GDM mice) compared to that without treatment (p<0.05). POSTN-siRNA (pAdEasy-m-POSTN shRNA) promoted PPARα gene transcription (p<0.05) and inhibited NF-kB/TNF-α gene transcription (p<0.05) in glucose-treated HTR8 cells (GDM mice) compared to those without treatment. POSTN-siRNA modulated NF-kB/TNF-α pathway mediated inflammation by regulating PPARα in HTR8 cells and GDM mice. PPARα participated in POSTN-associated inflammation. pAdEasy-m-POSTN shRNA inhibited T-CHO/TG levels in GDM mice compared to those without treatment (p<0.05). All the effects of POSTN-siRNA (pAdEasy-m-POSTN shRNA) were obviously blocked by PPARα inhibitor treatment. POSTN levels were significantly higher in pregnant women with GDM and were associated with chronic inflammation and PPARα expression. POSTN may act as a bridge between GDM and chronic inflammation to modulate insulin resistance by modulating PPARα/NF-κB/TNF-α signaling pathway.

Long Non-Coding RNA TUG1 Attenuates Insulin Resistance in Mice with Gestational Diabetes Mellitus via Regulation of the MicroRNA-328-3p/SREBP-2/ERK Axis.

Long non-coding RNAs (lncRNAs) have been illustrated to contribute to the development of gestational diabetes mellitus (GDM). In the present study, we aimed to elucidate how lncRNA taurine upregulated gene 1 (TUG1) influences insulin resistance (IR) in a high-fat diet (HFD)-induced mouse model of GDM. We initially developed a mouse model of HFD-induced GDM, from which islet tissues were collected for RNA and protein extraction. Interactions among lncRNA TUG1/microRNA (miR)-328-3p/sterol regulatory element binding protein 2 (SREBP-2) were assessed by dual-luciferase reporter assay. Fasting blood glucose (FBG), fasting insulin (FINS), homeostasis model assessment of insulin resistance (HOMA-IR), HOMA pancreatic β-cell function (HOMA-β), insulin sensitivity index for oral glucose tolerance tests (ISOGTT) and insulinogenic index (IGI) levels in mouse serum were measured through conducting gain- and loss-of-function experiments. Abundant expression of miR-328 and deficient expression of lncRNA TUG1 and SREBP-2 were characterized in the islet tissues of mice with HFD-induced GDM. LncRNA TUG1 competitively bound to miR-328-3p, which specifically targeted SREBP-2. Either depletion of miR-328-3p or restoration of lncRNA TUG1 and SREBP-2 reduced the FBG, FINS, HOMA-β, and HOMA-IR levels while increasing ISOGTT and IGI levels, promoting the expression of the extracellular signal-regulated kinase (ERK) signaling pathway-related genes, and inhibiting apoptosis of islet cells in GDM mice. Upregulation miR-328-3p reversed the alleviative effects of SREBP-2 and lncRNA TUG1 on IR. Our study provides evidence that the lncRNA TUG1 may prevent IR following GDM through competitively binding to miR-328-3p and promoting the SREBP-2-mediated ERK signaling pathway inactivation.

Polyphyllin I alleviates inflammatory injury in mice with gestational diabetes through AMPK pathway

Our study aimed to detect the effects of polyphyllin I (PPI) on relieving gestational diabetes mellitus (GDM), and the possible mechanism. A mouse model of GDM was constructed. The effects of PPI on GDM mice were evaluated by detecting blood glucose, insulin level, glucose tolerance test, and insulin tolerance test. The inflammation response in GDM and GDM+PPI group were evaluated by enzyme-linked immunosorbent assay (ELISA). The effect of PPI on the offspring of GDM mice was analyzed. In addition, immunoblot assays were performed to investigate the effects of PPI on the AMPK pathway. We found that PPI improved diabetes-related symptoms and decreased serum inflammatory response in GDM mice. In addition, we also found that PPI reduced the tissue damage of GDM mice. We noticed that PPI alleviated inflammatory injury in GDM mice through targeting AMPK pathway. Our findings showed that PPI has the potential to be explored as the drug for GDM treatment.

A novel model of gestational diabetes: Acute high fat high sugar diet results in insulin resistance and beta cell dysfunction during pregnancy in mice.

Gestational diabetes mellitus (GDM) affects 7-18% of all pregnancies. Despite its high prevalence, there is no widely accepted animal model. To address this, we recently developed a mouse model of GDM. The goal of this work was to further characterize this animal model by assessing insulin resistance and beta cell function. Mice were randomly assigned to either control (CD) or high fat, high sugar (HFHS) diet and mated 1 week later. At day 0 (day of mating) mice were fasted and intraperitoneal insulin tolerance tests (ipITT) were performed. Mice were then euthanized and pancreata were collected for histological analysis. Euglycemic hyperinsulinemic clamp experiments were performed on day 13.5 of pregnancy to assess insulin resistance. Beta cell function was assessed by glucose stimulated insulin secretion (GSIS) assay performed on day 0, 13.5 and 17.5 of pregnancy. At day 0, insulin tolerance and beta cell numbers were not different. At day 13.5, glucose infusion and disposal rates were significantly decreased (p<0.05) in Pregnant (P) HFHS animals (p<0.05) suggesting development of insulin resistance in P HFHS dams. Placental and fetal glucose uptake was significantly increased (p<0.01) in P HFHS dams at day 13.5 of pregnancy and by day 17.5 of pregnancy fetal weights were increased (p<0.05) in P HFHS dams compared to P CD dams. Basal and secreted insulin levels were increased in HFHS fed females at day 0, however at day 13.5 and 17.5 GSIS was decreased (p<0.05) in P HFHS dams. In conclusion, this animal model results in insulin resistance and beta cell dysfunction by mid-pregnancy further validating its relevance in studying the pathophysiology GDM.

Dysregulation of Mir-193B and Mir-376A as a Biomarker of Prediabetes in Offspring of Gestational Diabetic Mice

Gestational diabetes mellitus (GDM) is a type of diabetes initiated during pregnancy and is characterized by maternal hyperglycemia that induces complications in mothers and children. In the current study, we used a GDM mouse model (through i.p. injection of a single dose of streptozocin, STZ, 60 mg/kg/bw) to investigate the biochemical and immunological changes in the blood and brain of diabetic mothers and their offspring relative to their appropriate controls. In addition, we estimated the expression levels of a set of microRNAs (miRNAs) to link between the dysregulation in the levels of miRNAs and the exposure to oxidative stress during embryonic development, as well as metabolic changes that occur after birth and during puberty in offspring (5-weeks-old). At the biochemical level, newborn pups appeared mostly to suffer from the same oxidative stress conditions of their mothers as shown by the significant increase in nitric oxide (NO) and malondialdehyde (MDA) in blood and brain of diabetic mothers and their pups. However, the 5-week-old offspring showed a significant increase in proinflammatory cytokines, IL-1β, IL-6, and TNF-α, and based on their blood glucose levels, could be considered as prediabetic (with glucose mean value of 165 mg/dl). In the meantime, the tested miRNAs, especially miR-15b, miR-146a, and miR-138 showed mostly similar expression levels in diabetic mothers and newborn pups. In this regard, miR-15a and -15b, miR-146a, and miR-138 are downregulated in diabetic mothers and their newborn pups relative to their appropriate controls. However, in offspring of diabetic mothers at puberty age, these miRNAs displayed different expression levels relative to mothers and control offspring. Interestingly, miR-193 and miR-763 expression levels were significantly lower in diabetic mothers but upregulated in their 5-week-old offspring, suggesting that miR-193 and miR-763 could be used as biomarkers to differentiate between prediabetes and diabetes.

Human placenta mesenchymal stem cell-derived exosome shuttling microRNA-130b-3p from gestational diabetes mellitus patients targets ICAM-1 and perturbs human umbilical vein endothelial cell angiogenesis.

The aim of this study was to investigate the roles of miR-130b-3p and ICAM-1 in gestational diabetes mellitus (GDM) and their potential association. Human placenta mesenchymal stem cells (PlaMSCs) were isolated from GDM patients, and the effects of the PlaMSCs from GDM patients (GDM-MSCs) and the exosomes secreted by GDM-MSCs on human umbilical vein endothelial cell (HUVEC) proliferation, migration, and angiogenesis were detected. Next, GDM-MSCs were transfected with miR-130b-3p antagomir to modify miR-130b-3p expression in GDM-MSCs-derived exosomes, and the exosomes with modified miR-130b-3p expression were cultured with HUVECs to evaluate exosomal miR-130b-3p on HUVEC function. Furthermore, a target gene of miR-130b-3p was predicted and assessed. The miR-130b-3p-modified exosomes were cultured with HUVECs transfected with ICAM-1 shRNA to determine the effect of miR-130b-3p-ICAM-1 crosstalk on HUVEC function. Additionally, a GDM mouse model was conducted to further study the effect of miR-130b-3p in GDM in vivo. GDM-MSCs inhibited HUVEC proliferation and angiogenesis. The elevated expression of miR-130b-3p was found in GDM-MSCs-derived exosomes. GDM-MSCs-derived exosomes repressed the proliferation and angiogenesis of HUVECs and miR-130b-3p inhibition could restrain the inhibition of the exosomes on HUVEC function. Mechanistically, miR-130b-3p downregulated ICAM-1 expression in a targeted manner, and thereby enhanced HUVEC proliferation, migration, and angiogenesis and increased the expression of angiogenesis-related factors. Moreover, miR-130b-3p inhibition promoted placental angiogenesis in GDM mice and upregulated ICAM-1 expression. Conclusively, GDM-MSCs-derived exosomes shuttling miR-130b-3p repressed proliferation, migration, and angiogenesis of HUVECs by regulating ICAM-1 expression.

Long-noncoding RNA HOXA transcript at the distal tip ameliorates the insulin resistance and hepatic gluconeogenesis in mice with gestational diabetes mellitus via the microRNA-423-5p/wingless-type MMTV integration site family member 7A axis

ABSTRACT Long-noncoding RNA HOXA transcript at the distal tip (HOTTIP) has been probed to exert essential effects on diabetes progression, while its function in gestational diabetes mellitus (GDM) remains unclear. This study was committed to unravel the effects of HOTTIP on GDM progression via the microRNA (miR)-423-5p/wingless-type MMTV integration site family member 7A (WNT7A) axis. The GDM mouse model was established. HOTTIP, miR-423-5p and WNT7A levels in GDM mice were examined. The saline with dissolved various constructs altering HOTTIP, miR-423-5p and WNT7A expression was injected into GDM mice to detect the levels of GDM‐related biochemical indices, HOMA indices, liver gluconease: expression levels of phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G-6-Pase), glucose transporter 2 (GLUT2) and pathological changes of pancreatic tissues, and the apoptosis rate of pancreatic cells in GDM mice. The relations among HOTTIP, miR-423-5p and WNT7A were validated. HOTTIP and WNT7A levels were decreased while miR-423-5p was elevated in GDM mice. The enriched HOTTIP or silenced miR-423-5p alleviated the levels of GDM‐relatedbiochemical indices, enhanced the insulin homeostasis, elevated GLUT2 expression and decreased G-6-pase and PEPCK expression, mitigated the pathological changes of pancreatic tissues, and hindered the apoptosis of pancreatic cells. MiR-143-5p upregulation abrogated the effects of elevated HOTTIP on repressing GDM; whereas WNT7A deletion reversed the therapeutic effects of reduced miR-423-5p. HOTTIP sponged miR-423-5p that targeted WNT7A. HOTTIP ameliorates insulin resistance and hepatic gluconeogenesis in GDM mice via the modulation of the miR-423-5p/WNT7A axis. This study affords novel therapeutic modalities for GDM treatment.

Hepatic IGF2/H19 Epigenetic Alteration Induced Glucose Intolerance in Gestational Diabetes Mellitus Offspring via FoxO1 Mediation.

ObjectiveThe offspring of women with gestational diabetes mellitus (GDM) have a high predisposition to developing type 2 diabetes during childhood and adulthood. The aim of the study was to evaluate how GDM exposure in the second half of pregnancy contributes to hepatic glucose intolerance through a mouse model.MethodsBy creating a GDM mouse model, we tested glucose and insulin tolerance of offspring by intraperitoneal glucose tolerance test (IPGTT), insulin tolerance test (ITT), and pyruvate tolerance test (PTT). In addition, we checked the expression of genes IGF2/H19, FoxO1, and DNMTs in the mouse liver by RT-qPCR. Pyrosequencing was used to detect the methylation status on IGF2/H19 differentially methylated regions (DMRs). In vitro insulin stimulation experiments were performed to evaluate the effect of different insulin concentrations on HepG2 cells. Moreover, we detect the interaction between FoxO1 and DNMT3A by chromatin immunoprecipitation–quantitative PCR (Chip-qPCR) and knock-down experiments on HepG2 cells.ResultsWe found that the first generation of GDM offspring (GDM-F1) exhibited impaired glucose tolerance (IGT) and insulin resistance, with males being disproportionately affected. In addition, the expression of imprinted genes IGF2 and H19 was downregulated in the livers of male mice via hypermethylation of IGF2-DMR0 and IGF2-DMR1. Furthermore, increased expression of transcriptional factor FoxO1 was confirmed to regulate DNMT3A expression, which contributed to abnormal methylation of IGF2/H19 DMRs. Notably, different insulin treatments on HepG2 demonstrated those genetic alterations, suggesting that they might be induced by intrauterine hyperinsulinemia.ConclusionOur results demonstrated that the intrauterine hyperinsulinemia environment has increased hepatic FoxO1 levels and subsequently increased expression of DNMT3A and epigenetic alterations on IGF2/H19 DMRs. These findings provide potential molecular mechanisms responsible for glucose intolerance and insulin resistance in the first male generation of GDM mice.

Integrated Multi-Omics Analysis Reveals the Effect of Maternal Gestational Diabetes on Fetal Mouse Hippocampi.

Growing evidence suggests that adverse intrauterine environments could affect the long-term health of offspring. Recent evidence indicates that gestational diabetes mellitus (GDM) is associated with neurocognitive changes in offspring. However, the mechanism remains unclear. Using a GDM mouse model, we collected hippocampi, the structure critical to cognitive processes, for electron microscopy, methylome and transcriptome analyses. Reduced representation bisulfite sequencing (RRBS) and RNA-seq in the GDM fetal hippocampi showed altered methylated modification and differentially expressed genes enriched in common pathways involved in neural synapse organization and signal transmission. We further collected fetal mice brains for metabolome analysis and found that in GDM fetal brains, the metabolites displayed significant changes, in addition to directly inducing cognitive dysfunction, some of which are important to methylation status such as betaine, fumaric acid, L-methionine, succinic acid, 5-methyltetrahydrofolic acid, and S-adenosylmethionine (SAM). These results suggest that GDM affects metabolites in fetal mice brains and further affects hippocampal DNA methylation and gene regulation involved in cognition, which is a potential mechanism for the adverse neurocognitive effects of GDM in offspring.

MicroRNA-195-5p facilitates endothelial dysfunction by inhibiting vascular endothelial growth factor A in gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is a common disorder during pregnancy associated with endothelial dysfunction in the placental vasculature. MicroRNAs (miRNAs), which are short noncoding RNAs that modulate post-transcriptional gene expression, affect GDM progression. MiR-195-5p was reported to be a putative biomarker for GDM diagnosis, whose expression was markedly elevated in serum of GDM patients. Therefore, our study intended to explore whether miR-195-5p regulates endothelial cell dysfunction in GDM. Human placental microvascular endothelial cells (hPMECs) were treated with high concentration of glucose to establish an in vitro GDM model. The apoptosis, proliferation and angiogenesis of hPMECs were detected by flow cytometry analysis, CCK-8 assay and tube formation assay. The binding between vascular endothelial growth factor A (VEGFA) and miR-195-5p was verified by luciferase reporter assay. GDM mouse model was established by intraperitoneal injection of streptozocin. Cell apoptosis and the pathological changes in GDM mouse placenta tissues were evaluated by TUNEL staining and HE staining. Gene expression was detected by RT-qPCR. Protein levels were evaluated by western blotting. In this study, miR-195-5p knockdown promoted the proliferation and angiogenesis as well as inhibited the apoptosis of HG-treated hPMECs. MiR-195-5p targeted VEGFA, whose expression was downregulated in HG-treated hPMECs. VEGFA silencing antagonized the influence of miR-195-5p knockdown on the phenotypes of HG-treated hPMECs. Additionally, miR-195-5p inhibition decelerated cell apoptosis and improved pathological changes in GDM mouse placenta tissues. MiR-195-5p level was negatively correlated to VEGFA level in GDM mouse placenta tissues. Overall, miR-195-5p facilitates the endothelial cell dysfunction by inhibiting VEGFA in GDM.

Asperulosidic Acid, a Bioactive Iridoid, Alleviates Placental Oxidative Stress and Inflammatory Responses in Gestational Diabetes Mellitus by Suppressing NF-κB and MAPK Signaling Pathways

Background: Asperulosidic acid (ASP) is a bioactive iridoid exerting broad pharmacological and medicinal properties. However, it is still unknown if ASP has therapeutical effects on gestational diabetes mellitus (GDM). This study aims to evaluate the effects of ASP on GDM as well as its underlying mechanism. Methods: A mouse model of GDM was established and orally administrated ASP (10, 20, and 40 mg/kg) on gestation day (GD) 0. The mice were sacrificed on GD 18. Results: Blood glucose and serum insulin were then determined. The inflammatory cytokines including IL-6 and TNF-α and oxidative stress biomarkers including MDA, SOD, GSH, and GPx were determined by using specific ELISAs. In addition, the expressions of NF-κB and MAPK signaling pathway-related proteins were determined by using Western blotting. Treatment with ASP decreased blood glucose in the mouse model of GDM. Besides, ASP also increased serum insulin and attenuated β-cell function. Treatment with ASP suppressed IL-6 and TNF-α and regulated oxidative stress-related biomarkers. Western blotting analysis showed that treatment with ASP suppressed phosphorylation of NF-κB p65, ERK1/2, and p38 in placental tissues. Conclusion: ASP alleviates placental oxidative stress and inflammatory responses in GDM by the inhibition of the NF-κB and MAPK signaling pathways.

MiR-210-3p Impairs Pancreatic β-Cell Function by Targeting Dtx1 in Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM), a common complication in pregnancy, could threaten the health of both pregnancies and their offspring. miR-210-3p has been reported that play a crucial role in many diseases. Nevertheless, the molecular mechanism and clinical significance of miR-210-3p in the GDM is still unclear. miR-210-3p was overexpressed in the pancreas of the GDM mouse model. Meanwhile, miR-210-3p weakens cell viability and promotes the apoptosis of pancreatic β cells, impairing the function of pancreatic β cells. Bioinformatics analysis showed that miR-210-3p directly targets the expression of Dtx1, and miR-210-3p negatively regulated dtx1. Down-expression of Dtx1 could increase the expression of insulin and boost the function of pancreatic β cells through inhibiting expressions of p-Akt, p-mTOR, p-4E-BP1, and p-SGK1. Rescue experiments verified that miR-210-3p could regulate the function of pancreatic β cells and adjust the content of TG, TC, and HDL in the blood of mice with GDM via regulating the expression of Dtx1. The study demonstrated that miR-210-3p is significantly overexpressed in the pancreas of the GDM mouse model, which could impair the function and cell viability of pancreatic β cells via suppressing the expression of Dtx1 promotes the progression of GDM. These findings provide a novel strategy to treat GDM.

The mitochondrial-derived peptide MOTS-c relieves hyperglycemia and insulin resistance in gestational diabetes mellitus

The most common complication during pregnancy, gestational diabetes mellitus (GDM), can cause adverse pregnancy outcomes and result in the mother and infant having a higher risk of developing type 2 diabetes after pregnancy. However, existing therapies for GDM remain scant, with the most common being lifestyle intervention and appropriate insulin treatment. MOTS-c, a mitochondrial-derived peptide, can target skeletal muscle and enhance glucose metabolism. Here, we demonstrate that MOTS-c can be an effective treatment for GDM. A GDM mouse model was established by short term high-fat diet combined with low-dose streptozotocin (STZ) treatment while MOTS-c was administrated daily during pregnancy. GDM symptoms such as blood glucose and insulin levels, glucose and insulin tolerance, as well as reproductive outcomes were investigated. MOTS-c significantly alleviated hyperglycemia, improved insulin sensitivity and glucose tolerance, and reduced birth weight and the death of offspring induced by GDM. Similar to a previous study, MOTS-c also could activate insulin sensitivity in the skeletal muscle of GDM mice and elevate glucose uptake in vitro. In addition, we found that MOTS-c protects pancreatic β-cell from STZ-mediated injury. Taken together, our findings demonstrate that MOTS-c could be a promising strategy for the treatment of GDM.