Protective effect of sRAGE on fetal development in pregnant rats with gestational diabetes mellitus

Pharmacological Action of Baicalin on Gestational Diabetes Mellitus in Pregnant Animals Induced by Streptozotocin via AGE-RAGE Signaling Pathway

OBJECTIVE

Baicalin (BC) is a flavonoid reported to have various pharmacological activities, including antioxidant, anti-cancer, anti-inflammatory, anti-allergy, immune regulation, and anti-diabetic. This study examines the probable mechanism for gestational diabetes mellitus (GDM) brought on by streptozotocin (STZ) and the impact of BC on fetal development via AGEs (advanced serum glycation end products) and RAGE (the role of advanced glycation end products).

MATERIAL AND METHOD

STZ has been used in the current experimental study to induce diabetes mellitus in pregnant animals (gestational diabetes mellitus). GDM pregnant animals were separated into five groups and were treated with BC in a dose-dependent pattern for 19 days. At the end of the experiment, the fetus and blood samples were drawn from all the pregnant rats to assess the biochemical parameter as well as AGE-RAGE.

RESULT

Administration of BC at varying doses leads to enhancement in the weight of the fetus body and placenta while gestational diabetic pregnant animals induced by STZ had a lower weight of the fetus body and placenta. The dose-dependent pattern of BC also enhanced fasting insulin (FINS), high-density lipoprotein (HDL), serum insulin, and hepatic glycogen. It also significantly enhanced the content of the antioxidant profile and pro-inflammatory cytokines and modulated the gene expression (VCAM- 1, p65, EGFR, MCP-1, 1NOX2, and RAGE) in various tissues in gestational diabetes mellitus pregnant rats.

CONCLUSION

Baicalin demonstrated the potential impact on the embryo's development via the AGE-RAGE signaling pathway in STZ-induced GDM pregnant animals.

Maternal n-7 Unsaturated Fatty Acids Protect the Fetal Brain from Neuronal Degeneration in an Intrauterine Hyperglycemic Animal Model

We previously reported that glycation induces insulin resistance in the hearts of newborn pups from a gestational diabetes mellitus (GDM) rat model. Administration of n-3 unsaturated fatty acids suppressed glycation and improved signaling in GDM rat pups. In this study, we investigated their effects on cranial neurons using the GDM rat model and PC12 cells derived from rat adrenal pheochromocytomas. Additionally, we examined whether n-3 and n-7 unsaturated fatty acids (cis-palmitoleic acid [CPA] and trans-palmitoleic acid [TPA]) ameliorate the detrimental effects of high glucose exposure on rats. In the neonatal cerebrum of GDM rats, increased levels of advanced glycation end products (AGEs) inhibited Akt phosphorylation; however, CPA and TPA intake during pregnancy ameliorated these abnormalities. Furthermore, exposure to high-glucose-induced apoptosis in PC12 cells compared to the cells cultured in control glucose. PC12 cells exposed to high-glucose with fatty acids exhibited reduced AGE production and apoptosis induction compared to the high-glucose group. These findings suggest that a hyperglycemic environment during pregnancy promotes AGE formation in brain neuronal proteins and induces apoptosis. Both TPA and CPA mitigated these abnormalities; however, CPA is cytotoxic, highlighting its safety in pregnant women.

RAGE against the Machine: Can Increasing Our Understanding of RAGE Help Us to Battle SARS-CoV-2 Infection in Pregnancy?

The receptor of advanced glycation end products (RAGE) is a receptor that is thought to be a key driver of inflammation in pregnancy, SARS-CoV-2, and also in the comorbidities that are known to aggravate these afflictions. In addition to this, vulnerable populations are particularly susceptible to the negative health outcomes when these afflictions are experienced in concert. RAGE binds a number of ligands produced by tissue damage and cellular stress, and its activation triggers the proinflammatory transcription factor Nuclear Factor Kappa B (NF-κB), with the subsequent generation of key proinflammatory cytokines. While this is important for fetal membrane weakening, RAGE is also activated at the end of pregnancy in the uterus, placenta, and cervix. The comorbidities of hypertension, cardiovascular disease, diabetes, and obesity are known to lead to poor pregnancy outcomes, and particularly in populations such as Native Hawaiians and Pacific Islanders. They have also been linked to RAGE activation when individuals are infected with SARS-CoV-2. Therefore, we propose that increasing our understanding of this receptor system will help us to understand how these various afflictions converge, how forms of RAGE could be used as a biomarker, and if its manipulation could be used to develop future therapeutic targets to help those at risk.

Protective effect of sinomenine against inflammation and oxidative stress in gestational diabetes mellitus in female rats via TLR4/MyD88/NF-κB signaling pathway

Gestational diabetes mellitus (GDM) is a dangerous complication of pregnancy which is induced via dysfunction in glucose metabolism during pregnancy. Sinomenine (SM) has already proved an antidiabetic effect against streptozotocin (STZ)-induced diabetes mellitus (DM) in rats. In this protocol, we examined the protective effect of SM against STZ-induced GDM in rats. Wistar rats were divided into three groups and STZ (40 mg/kg) was used to induce GDM. At the end of the experimental protocol, bodyweight, pub weight, and survival rate were estimated. Blood glucose level (BGL), fasting insulin (FINS), free fatty acid (FFA), Hemoglobin A1C (HbA1c), and C-peptide were measured. Lipid, antioxidant, inflammatory cytokines, and inflammatory mediators were also determined. RT-PCR was used for estimation of the role of TLR4/MyD88/NF-κB signaling pathway. SM treatment significantly (p < .001) reduced BGL, hepatic glycogen, and improved the levels of FINS, C-peptide, FFA, and HbA1c. SM significantly (p < .001) suppressed the levels of total cholesterol (TC), low-density lipoprotein (LDL), triglycerides (TG), coronary artery index (CAI), very low-density lipoprotein (VLDL), atherogenic index (AI), and boosted high-density lipoprotein (HDL) levels. SM significantly (p < .001) decreased the lipid peroxidation (LPO) level and enhanced glutathione peroxidase (GPx), total antioxidant capacity (TAC), glutathione S-transferase (GST), superoxide dismutase (SOD), respectively. It reduced the levels of inflammatory cytokines including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and inflammatory mediators viz., nuclear kappa B factors (NF-κB). SM significantly (p < .001) reduced the mRNA expression of Myd88, NLRP3, TLR4, and NF-κB, which were boosted in the GDM group rats. These findings suggest that SM could be a probable drug to be used for treating GDM via inhibition of the TLR4 signaling pathway. PRACTICAL APPLICATIONS: It is well known that gestational diabetes mellitus (GDM) is a dangerous health problem during the pregnancy. SM reduced the glucose level; boosted the level of fasting insulin (FINS) and bodyweight. SM significantly improved the number of pubs and their survival rates. SM suppressed oxidative stress and inflammation via activation of TLR4/MyD88/NF-κB signaling pathway. According to our research, SM can be used as a preventive drug in the treatment of GDM during pregnancy.

Crocetin suppresses gestational diabetes in streptozotocin-induced diabetes mellitus rats via suppression of inflammatory reaction

Gestational diabetes mellitus (GDM) is the serious complication of pregnancy induced via dysfunction in glucose metabolism during the pregnancy. Crocetin already proved antidiabetic effect in streptozotocin (STZ)-induced diabetes mellitus in rats. In this protocol, we have investigated the potential effect of crocetin against STZ-induced GDM in rats. Wistar rats were used for the current protocol; STZ was used for the induction for DM and finally caused the GDM. Body weight and serum advanced glycation end products level were estimated at regular time intervals. We also estimated the fetus weight and placental weight. Biochemical, antioxidant, pro-inflammatory cytokines, inflammatory mediators, and apoptosis parameters were estimated. mRNA expression of NOX2, RAGE, MCP-1, VCAM-1, EGFR, and p65 were also estimated. Crocetin treatment significantly (p < .001) reduced the fetus weight and increased the placental weight and index. Crocetin significantly (p < .001) reduced the blood glucose level and increased the body weight. Crocetin significantly (p < .001) boosted the level of antioxidant enzymes and includes superoxide dismutase, glutathione peroxidase, glutathione, and catalase. Crocetin significantly (p < .001) altered the level of lipid parameters and pro-inflammatory cytokines. Crocetin significantly (p < .001) reduced the level of intercellular adhesion molecule 1, cyclooxygenase-2, and nuclear factor kappa B and increased the level of visfatin against GDM rats. Crocetin significantly (p < .001) altered the level of mRNA expression. Based on the result, we can say that crocetin is a protective drug against the GDM in pregnant rats via antioxidant, inflammatory, and apoptosis parameters. PRACTICAL APPLICATIONS: As we all know, gestational diabetes mellitus (GDM) cases rise all over the world. The current investigation showed the protective effect of crocetin on GDM in experimental rats. The current finding exhibited the protective effect of crocetin against STZ-induced GDM via suppression of inflammatory, oxidative, and apoptosis parameters. The result suggests the antioxidant and anti-inflammatory effect of crocetin. Crocetin can be used as a preventive medication in the treatment of gestational diabetes mellitus, according to the latest findings.

Early AGEing and metabolic diseases: is perinatal exposure to glycotoxins programming for adult-life metabolic syndrome?

Perinatal early nutritional disorders are critical for the developmental origins of health and disease. Glycotoxins, or advanced glycation end-products, and their precursors such as the methylglyoxal, which are formed endogenously and commonly found in processed foods and infant formulas, may be associated with acute and long-term metabolic disorders. Besides general aspects of glycotoxins, such as their endogenous production, exogenous sources, and their role in the development of metabolic syndrome, we discuss in this review the sources of perinatal exposure to glycotoxins and their involvement in metabolic programming mechanisms. The role of perinatal glycotoxin exposure in the onset of insulin resistance, central nervous system development, cardiovascular diseases, and early aging also are discussed, as are possible interventions that may prevent or reduce such effects.

Therapeutic effect of ursolic acid on fetal development in pregnant rats with gestational diabetes mellitus via AGEs-RAGE signaling pathway

To investigate the effect of ursolic acid on the fetal development of gestational diabetes mellitus (GDM) caused by streptozotocin (STZ) and explore the potential mechanism for it. For the current experimental research, SD rats (pregnant animal) were used. STZ has been used to cause the diabetes mellitus in pregnant rats. Rats with evolved GDM were randomly divided and ursolic acid was given to pregnant rats in the experimental period up to 19 days in a dose-dependent manner. Blood samples and fetal rats of all group rats were collected at 19 days (pregnant rats), fetal rats and placental rats were weighted and the blood glucose, plasma insulin, C-peptide, and lipid parameters of pregnant women were estimated prior to delivery. Advanced serum glycation end-products (AGEs) were estimated at regular intervals in the heart and brain of pregnant rats. Monocyte Chemoattractant Protein-1 (MCP-1), NADPH oxidase 2 (Nox2), Role of advanced glycation end product (RAGE), Vascular endothelial growth factor (VEGF), p65, and vascular cell adhesion molecule 1 (VCAM-1) mRNA expression were estimated in the placenta. STZ-induced GDM pregnant rats showed significantly decreased placental weight and weight of fetal rats and dose-dependent ursolic acid treatment (p < .001) improved placental weight and weight of fetal rats at dose-dependent levels. After the ursolic acid treatment, serum blood glucose and lipid level were improved especially fasting blood glucose (FBG), high density lipoprotein (HDL), hepatic glycogen, fasting insulin (FINS), and serum insulin level and reached near to the normal control group rats. The antioxidant level of pancreas and liver were significantly (p < .001) reduced by the dose-dependent treatment of ursolic acid. Treatment with Ursolic acid moderately but not significantly decreases the risk of fetal development defects relative to the GDM group. The potential effect on fetal development in Pregnant Rats with Gestational Diabetes Mellitus via AGEs-RAGE signaling pathway was shown by Ursolic acid. PRACTICAL APPLICATIONS: As we know that the gestational diabetes mellitus increases worldwide day by day. In the current experimental study, we try to examine the gestational diabetic effect of ursolic acid. The finding of the current study showed the gestational diabetic protective effect in the female rats via AGEs-RAGE signaling pathway. The result showed the antioxidant, anti-inflammatory, and biochemical parameters. On the basis of the result, we can say that the ursolic acid can be the protective drug for treatment of gestational diabetes mellitus.

Placental Morphology and Cellular Characteristics in Stillbirths in Women With Diabetes and Unexplained Stillbirths

CONTEXT.—

Women with diabetes have increased stillbirth risk. Although the underlying pathophysiological processes are poorly understood, stillbirth is frequently related to abnormal placental structure and function.

OBJECTIVE.—

To investigate placental morphology and cellular characteristics in the placentas of women with diabetes who had stillbirths and stillbirths of unexplained cause.

DESIGN.—

Placentas from women with uncomplicated live births, live births in women with diabetes, unexplained stillbirths, and stillbirths related to diabetes (n = 10/group) underwent clinical histopathologic assessment and were also investigated using immunohistochemical staining to quantify syncytial nuclear aggregates, proliferation, trophoblast area, vascularization, T cells, placental macrophages (Hofbauer cells), and the receptor for advanced glycation end products.

RESULTS.—

Ki67+ cells were decreased in unexplained stillbirths compared with live births in women with diabetes. Both stillbirth groups had increased cytokeratin 7+/nuclear area compared with controls. Blood vessels/villi were decreased in unexplained stillbirth compared with live births from women with diabetes. Compared with uncomplicated controls, CD163+ macrophages were increased in live births in women with diabetes and unexplained stillbirths, and further increased in stillbirths related to diabetes. There was no change in CD3+ T cells or syncytial nuclear aggregates. Receptor for advanced glycation end products-positive cells were decreased in both stillbirth groups compared with diabetes-related live births. Co-localization of receptor for advanced glycation end products in macrophages was increased in both stillbirth groups compared with live birth groups.

CONCLUSIONS.—

Stillbirths related to diabetes exhibit placental phenotypic differences compared with live births. Further investigation of these parameters may provide understanding of the pathologic mechanisms of stillbirth and aid the development of stillbirth prevention strategies.

The role of advanced glycation end products in human infertility

Advanced glycation end products (AGEs) are heterogeneous products of the non-enzymatic interaction between proteins and reducing sugars. Numerous studies have shown that AGEs are associated with senescence, diabetes, vascular disease, aging and kidney disease. Infertility has been affected approximately 10 to15% of couples of reproductive ages. AGEs accumulation has been shown to play a crucial role in pathogenesis of infertility-related diseases. The present review provides the generation process, mechanism and pathological significance of AGEs and the novel treatment targeting AGEs for infertility.

Advanced glycation end products increased placental vascular permeability of human BeWo cells via RAGE/NF-kB signaling pathway

OBJECTIVE

This study aimed to investigate the mechanisms of advanced glycation end products (AGEs) on cell tight conjunction and placental vascular permeability in BeWo cells.

STUDY DESIGN

Monolayer permeability assay and transmission electron microscopy were employed to reveal the transformation of the placental vascular permeability and cell tight conjunction. Immunofluorescence, western blot and RT-qPCR were adopted to determine the protein and mRNA levels. Anti-RAGE and NF-kB inhibitor (PDTC) were used to inactivate the RAGE/NF-kB signaling pathway.

RESULTS

AGEs significantly decreased trans-epithelial electrical resistance (TEER), while increased paracellular permeability (P <  0.05). TEM showed that AGEs made cell junction loose. AGEs inhibited ZO-1 and Occludin expressions, while anti-RAGE or PDTC partially restored their levels. AGEs also significantly increased mRNA RAGE and NF-kB expressions in BeWo cells (P <  0.05), and their expressions were inhibited by anti-RAGEy or PDTC.

CONCLUSION

AGEs could reduce the expressions of ZO-1 and Occludin by activating RAGE/NF-kB signaling pathway, thus increasing placental vascular permeability.

Thrombin/PAR-1 activation induces endothelial damages via NLRP1 inflammasome in gestational diabetes

Gestational diabetes mellitus (GDM) is associated with an increased risk of progressing to type 2 DM and cardiovascular disease; however, the pathogenesis is still poorly understood. This study was to investigate roles of thrombin and its receptor protease-activated receptor 1 (PAR-1) and NLRP1 inflammasome in endothelial injury in GDM condition. Umbilical cord and plasma of GDM patients and high glucose (HG) cultured human umbilical vein endothelial cells (HUVECs) were used to examine the pathological changes of these pathways. Meanwhile, ameliorative effects and potential mechanisms of a natural product sarsasapogenin (Sar) were investigated in HUVECs. Thrombin/PAR-1 pathway, advanced glycation endproducts (AGEs) and their receptor (RAGE) axis, and the nucleotide-binding domain and leucine-rich repeat containing protein 1 (NLRP1) inflammasome were activated in GDM condition and HG-cultured HUVECs, accompanied by endothelial injury (decreased cell viability and increased lactate dehydrogenase release). Nevertheless, thrombin inhibition or PAR-1 antagonism caused decreases in AGEs formation and RAGE expression in HG-cultured HUVECs, while AGEs inhibition or RAGE antagonism declined PAR-1 expression not thrombin activity. Furthermore, thrombin inhibition or PAR-1 antagonism restrained NLRP1 inflammasome activation in HG-cultured HUVECs; meanwhile, NLRP1 expression and interleukin 18 levels were remarkably reduced in HG-cultured HUVECs after PAR-1 knockdown. Interestingly, Sar co-treatment could suppress thrombin/PAR-1 pathway, NLRP1 inflammasome, and AGEs/RAGE axis. Together, endothelial damages in GDM were likely due to enhanced interaction between AGEs/RAGE axis and thrombin/PAR-1 pathway, followed by NLRP1 inflammasome activation. Moreover, Sar may act as a protective agent against endothelial injury in chronic HG condition.

Lactobacillus bulgaricus improves antioxidant capacity of black garlic in the prevention of gestational diabetes mellitus: a randomized control trial

Objectives:Lactobacillus bulgaricus may improve antioxidant capacity of black garlic in the prevention of gestational diabetes mellitus (GDM).

Methods: Black garlic was prepared with or without L. bulgaricus. Volatile and polysaccharides were analyzed by using LC-MS, Fourier Transform infrared (FTIR) and ¹³C nuclear magnetic resonance (NMR). The study design was parallel randomized controlled trial and 226 GDM patients were randomly assigned into BG (black garlic and L. bulgaricus) and CG (black garlic) groups, and allocation ratio was 1:1. The treatment duration was 40 weeks. Fasting blood glucose (FBG) and 1- and 2-h blood glucose (1hBG and 2hBG) after oral glucose tolerance test (OGTT) were detected. Antioxidant function of black garlic was determined by measuring plasma malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and total antioxidant capacity (T-AOC) in GDM patients. The comparison between two groups was made using two independent samples t test.

Results: The intake of nutrients was similar between two groups (P>0.05). L. bulgaricus promoted the transformation of the glucopyranoside to glucofuranoside. L. bulgaricus increased the abilities of black garlic for scavenging hydroxyl radicals, 2,2′-azino-bis (3-ethylbenzenthiazoline-6-sulfonic) acid (ABTS) and DPPH free radicals. L. bulgaricus reduced the levels of FBG, 1hBG and 2hBG, and incidence of perinatal complications (P<0.01). Plasma MDA level in the BG group was lower than in the CG group, whereas the levels of SOD, GSH-PX and T-AOC in the BG group were higher than in the CG group (P<0.01).

Conclusions:L. bulgaricus improves antioxidant capacity of black garlic in the prevention of GDM.

Skin Autofluorescence of Pregnant Women With Diabetes Predicts the Macrosomia of Their Children

Advanced glycation end products (AGEs) accumulated during long-term hyperglycemia are involved in diabetes complications and can be estimated by skin autofluorescence (sAF). During pregnancy, hyperglycemia exposes women to the risk of having a macrosomic newborn. The aim of this study was to determine whether sAF of women with diabetes during a singleton pregnancy could predict macrosomia in their newborns. Using an AGE Reader, we measured the sAF at the first visit of 343 women who were referred to our diabetology department during years 2011-2015. Thirty-nine women had pregestational diabetes, 95 early gestational diabetes mellitus (GDM), and 209 late GDM. Macrosomia was defined as birth weight ≥4,000 g and/or large for gestational age ≥90th percentile. Forty-six newborns were macrosomic. Their mothers had 11% higher sAF compared with other mothers: 2.03 ± 0.30 arbitrary units (AUs) vs. 1.80 ± 0.34 (P < 0.0001). Using multivariate logistic regression, the relation between sAF and macrosomia was significant (odds ratio 4.13 for 1-AU increase of sAF [95% CI 1.46-11.71]) after adjusting for several potential confounders. This relation remained significant after further adjustment for HbA_1c (among 263 women with available HbA_1c) and for women with GDM only. sAF of pregnant women with diabetes, a marker of long-term hyperglycemic exposure, predicts macrosomia in their newborns.

New Insights into the Process of Placentation and the Role of Oxidative Uterine Microenvironment

For a successful pregnancy to occur, a predecidualized receptive endometrium must be invaded by placental differentiated cells (extravillous trophoblast cells (EVTs)) and, at the same time, continue decidualization. EVT invasion is aimed at anchoring the placenta to the maternal uterus and ensuring local blood supply increase necessary to provide normal placental and foetal development. The first is achieved by migrating through the maternal endometrium and deeper into the myometrium, while the second by transforming uterine spiral arteries into large vessels. This process is a tightly regulated battle comprising interests of both the mother and the foetus. Invading EVTs are required to perform a scope of functions: move, adhere, proliferate, differentiate, interact, and digest the extracellular matrix (ECM); tolerate hypoxia; transform the maternal spiral arteries; and die by apoptosis. All these functions are modulated by their surrounding microenvironment: oxygen, soluble factors (e.g., cytokines, growth factors, and hormones), ECM proteins, and reactive oxygen species. A deeper comprehension of oxidative uterine microenvironment contribution to trophoblast function will be addressed in this review.

Late Cognitive Consequences of Gestational Diabetes to the Offspring, in a New Mouse Model

Gestational diabetes mellitus (GD) is a form of insulin resistance triggered during gestation, which affects approximately 10% of pregnant women. Although previously considered a transient condition with few long-term consequences, growing evidence suggest that GD may be linked to permanent metabolic and neurologic changes in the offspring. Currently available GD models fail to recapitulate the full spectrum of this disease, thus providing limited information about the true burden of this condition. Here, we describe a new mouse model of GD, based on the administration of an insulin receptor antagonist (S961, 30 nmol/kg s.c. daily) during pregnancy. Pregnant mice developed increased fasting glycemia and glucose intolerance in the absence of maternal obesity, with a return to normoglycemia shortly after parturition. Moreover, we showed that the adult offspring of GD dams presented pronounced metabolic and cognitive dysfunction when exposed to short-term high-fat diet (HFD). Our data demonstrate that S961 administration to pregnant mice comprises a valuable approach to study the complex pathophysiology of GD, as well as strategies focused on prevention and treatment of both the mother and the offspring. Our findings suggest that the offspring of GD mothers are more susceptible to metabolic and cognitive impairments when exposed to high-fat diet later in life, thus indicating that approaches to prevent and treat these late effects should be pursued.

Relationship between advanced glycation end products and gestational diabetes mellitus

Objective: To investigate the levels of and dynamic changes of advanced glycation end products (AGEs) in maternal plasma during pregnancy and explore the association between these levels and gestational diabetes mellitus (GDM). Methods: This study recruited 90 GDM women and 90 healthy pregnant controls. The women received prenatal care and were hospitalized for delivery in Peking University First Hospital in China between October 2015 and April 2016. The patients were recruited and provided blood samples during gestational weeks 24-29. The levels of AGEs, TNF-α, hs-CRP, plasma glucose, and FINS and lipid profiles were measured, and HOMA-IR was calculated. New blood samples were collected and AGE was measured again in the two groups at 33-41 weeks of gestation to identify its dynamic changes. Results: The levels of AGEs were significantly higher in the GDM group than in the NGT group at both 24-29 weeks (473.65 ± 105.32 versus 324.36 ± 57.86 ng/L; p < .001) and 33-41 weeks (533.47 ± 146.95 versus 315.50 ± 77.79 ng/L; p < .001), and plasma levels of TNF-α and hs-CRP were significantly higher in the GDM group than in the NGT group (282.58 ± 45.85 versus 177.54 ± 35.14 pg/mL; 1.11 ± 0.25 versus 0.6 ± 0.19 µg/mL; p < .001), even after adjusting for other confounding factors, AGE levels were positively correlated with the levels of 2hPG (p = .003), TNF-α (p = .005), and hs-CRP (p < .001). A logistic regression analysis showed that AGE (OR = 1.037, 95%CI: 1.017 ∼ 1.058) and TNF-α (OR = 1.115, 95%CI: 1.048 ∼ 1.186) levels were independent risk factors for GDM. In the GDM group, the concentration of AGEs was significantly higher at 33-41 weeks than at 24-29 weeks (p = .001). In the NGT group, there was no significant change in the concentration of AGEs between the two gestational periods (p = .388). Conclusions: Plasma levels of AGEs are associated with GDM. During pregnancy, the changes observed in the levels of AGEs were different between GDM and normal pregnancies.

Consequences of gestational diabetes to the brain and behavior of the offspring

Gestational diabetes mellitus (GD) is a form of insulin resistance triggered during the second/third trimesters of pregnancy in previously normoglycemic women. It is currently estimated that 10% of all pregnancies in the United States show this condition. For many years, the transient nature of GD has led researchers and physicians to assume that long-term consequences were absent. However, GD diagnosis leads to a six-fold increase in the risk of developing type 2 diabetes (T2D) in women and incidence of obesity and T2D is also higher among their infants. Recent and concerning evidences point to detrimental effects of GD on the behavior and cognition of the offspring, which often persist until adolescence or adulthood. Considering that the perinatal period is critical for determination of adult behavior, it is expected that the intra-uterine exposure to hyperglycemia, hyperinsulinemia and pro-inflammatory mediators, hallmark features of GD, might affect brain development. Here, we review early clinical and experimental evidence linking GD to consequences on the behavior of the offspring, focusing on memory and mood disorders. We also discuss initial evidence suggesting that downregulation of insulin signaling cascades are seen in the brains of GD offspring and could contribute to the consequences on their behavior.

Decreased levels of sRAGE in follicular fluid from patients with PCOS

This study aimed to explore the association between soluble receptor for advanced glycation end products (sRAGE) levels in follicular fluid and the number of oocytes retrieved and to evaluate the effect of sRAGE on vascular endothelial growth factor (VEGF) in granulosa cells in patients with polycystic ovarian syndrome (PCOS). Two sets of experiments were performed in this study. In part one, sRAGE and VEGF protein levels in follicular fluid samples from 39 patients with PCOS and 35 non-PCOS patients were measured by ELISA. In part two, ovarian granulosa cells were isolated from an additional 10 patients with PCOS and cultured. VEGF and SP1 mRNA and protein levels, as well as pAKT levels, were detected by real-time PCR and Western blotting after cultured cells were treated with different concentrations of sRAGE. Compared with the non-PCOS patients, patients with PCOS had lower sRAGE levels in follicular fluid. Multi-adjusted regression analysis showed that high sRAGE levels in follicular fluid predicted a lower Gn dose, more oocytes retrieved, and a better IVF outcome in the non-PCOS group. Logistic regression analysis showed that higher sRAGE levels predicted favorably IVF outcomes in the non-PCOS group. Multi-adjusted regression analysis also showed that high sRAGE levels in follicular fluid predicted a lower Gn dose in the PCOS group. Treating granulosa cells isolated from patients with PCOS with recombinant sRAGE decreased VEGF and SP1 mRNA and protein expression and pAKT levels in a dose-dependent manner.

Chronic maternal hyperglycemia induced during mid-pregnancy in rats increases RAGE expression, augments hippocampal excitability, and alters behavior of the offspring

Maternal diabetes during pregnancy may increase the risk of neurodevelopmental disorders in the offspring by increasing inflammation. A major source of inflammatory signaling observed in diabetes is activation of the receptor for advanced glycation end-products (RAGE), and increased RAGE expression has been reported in psychiatric disorders. Thus, we sought to examine whether maternal diabetes creates a proinflammatory state, triggered largely by RAGE signaling, that alters normal brain development and behavior of the offspring. We tested this hypothesis in rats using the streptozotocin (STZ; 50mg/kg; i.p.) model of diabetes induced during mid-pregnancy. Following STZ treatment, we observed a significant increase in RAGE protein expression in the forebrain of the offspring (postnatal day 1). Data obtained from whole-cell patch clamping of hippocampal neurons in cultures from the offspring of STZ-treated dams revealed a striking increase in excitability. When tested in a battery of behavioral tasks in early adulthood, the offspring of STZ-treated dams had significantly lower prepulse inhibition, reduced anxiety-like behavior, and altered object-place preference when compared to control offspring. In an operant-based strategy set-shifting task, STZ offspring did not differ from controls on an initial visual discrimination or reversal learning but took significantly longer to shift to a new strategy (i.e., set-shift). Insulin replacement with an implantable pellet in the dams reversed the effects of maternal diabetes on RAGE expression, hippocampal excitability, prepulse inhibition and object-place memory, but not anxiety-like behavior or set-shifting. Taken together, these results suggest that chronic maternal hyperglycemia alters normal hippocampal development and behavior of the offspring, effects that may be mediated by increased RAGE signaling in the fetal brain.