A Triterpene Glycoside Fraction, TG from <i>Gymnema sylvestre</i>Ameliorates Insulin Resistance by Stimulating Glucose Uptake in 3T3L1 Adipocytes and C2C12 Skeletal Muscle Cells

Type 2 diabetes mellitus (T2DM) which is characterized by insulin resistance in muscle and adipose tissues is a major problem worldwide. Plant based medications are well known from ancient times for possessing antidiabetic properties. Amongst them, Gymnema sylvestre (GS) is one such antidiabetic medicinal plant which has been used traditionally over the years for the treatment of T2DM. The aim of the present study was to investigate the effect of triterpene glycoside (TG), an active fraction isolated from ethanolic extract of Gymnema sylvestre (EEGS) on a battery of targets;glucose transporter (GLUT- 4), peroxisome proliferator activator receptor gamma (PPAR-γ), adiponectin and leptin involved in glucose transport and metabolism. No cytotoxic effects were observed in treated cells up to 600 μg/ml of TG as measured by MTT and ROS assays. Elevation of GLUT-4 and PPAR-γ by TG in association with glucose transport supported the upregulation of glucose uptake at concentrations of 50 and 100 μg/ml respectively. Additionally, TG showed higher expression of adiponectin and leptin, confirming the favorable pharmacological effect of TG on insulin resistance. The results were comparable to the known antidiabetic drug pioglitazone and commercial standard DAG. Thus TG could be considered as a safe nutraceutical candidate/functional phytoingredient in amelioration of insulin resistance.

Anti-Hyperglycemic Effect of Single Administered Gardeniae Fructus in Streptozotocin-Induced Diabetic Mice by Improving Insulin Resistance and Enhancing Glucose Uptake in Skeletal Muscle

The mechanisms of Gardeniae Fructus (GF) for anti-hyperglycemic action were demonstrated in streptozotocin (STZ)-diabetic mice. Six hours after single intraperitoneal administration of GF (300 mg/kg) or H2O into 3 hour-fasted STZ-diabetic mice, glucose and insulin tolerances were assessed by intraperitoneal glucose (1.5 g/kg) tolerance test (IPGTT) and intraperitoneal insulin (0.65 U/kg) tolerance test (IPITT), respectively. Effects of GF on insulin signaling pathways in soleus muscle such as glucose uptake, expression of glucose transporter 4 (GLUT4) in the plasma membrane and phosphorylation of Akt (P-Akt) in cytosolic fraction were examined in STZ-diabetic mice. In IPGTT test, GF significantly accelerated clearance of exogenous glucose and its glucose-lowering action was greater than H2O-treated controlin STZ-diabetic mice. GF also promoted an exogenous glucose-increased insulin level in STZ-diabetic mice. In IPITT test, GF decreased glucose level to the greater extent than H2O-treated control in STZ-diabetic mice. Furthermore, GF significantly decreased high HOMA-IR in STZ-diabetic mice from 21.6 ± 2.4 to 12.4 ± 1.9 (mg/dl × μU/ml). These results implied that GF improved insulin resistance in STZ-diabetic mice. GF increased glucose uptake of soleus muscle 1.5 times greater than H2O-treated control in STZ-diabetic mice. GF enlarged insulin (10 nmol/ml)-increased glucose uptake to 1.8 time-greater. Correspondingly, GF increased expression of GLUT4 in the plasma membrane of soleus muscle to 1.4 time-greater, and P-Akt in the cytosolic fraction of soleus muscle to 1.9 time-greater than those in H2O-treated control. In conclusion, the improvement of GF on insulin resistance is associated with the repair of insulin signaling via P-Akt, GLUT4 and glucose uptake pathway in soleus muscle of STZ-diabetic mice.

超重/肥胖合并2型糖尿病患者血清ANGPTL4、HSP70、IL-34水平与胰岛素抵抗的相关性

目的 探讨超重/肥胖合并2型糖尿病(T2DM)患者血清血管生成素样蛋白4(ANGPTL4)、热休克蛋白(HSP)70、白细胞介素-34(IL-34)水平与胰岛素抵抗的相关性。方法 选取2020年5月—2022年5月保定市第一中心医院T2DM患者182例(T2DM组)。参考相关诊断标准,将T2DM患者分为超重/肥胖T2DM组(90例)和体重正常T2DM组(92例)。另选取同期健康体检者90名作为正常对照组,其中超重/肥胖者40名(超重/肥胖对照组)、体重正常者50名(体重正常对照组)。检测所有研究对象血清ANGPTL4、HSP70、IL-34、胰岛素和血糖水平,计算稳态模型胰岛素抵抗指数(HOMA-IR)。T2DM患者治疗3个月后,再次检测其血清ANGPTL4、HSP70、IL-34水平和HOMA-IR。采用Pearson相关分析评估血清ANGPTL4、HSP70、IL-34与HOMA-IR的相关性。结果 与正常对照组和体重正常T2DM组比较,超重/肥胖T2DM组血清ANGPTL4和HSP70显著降低(P<0.05),血清IL-34和HOMA-IR显著升高(P<0.05)。与正常对照组比较,体重正常T2DM组血清ANGPTL4和HSP70显著降低(P<0.05),血清IL-34和HOMA-IR显著升高(P<0.05)。Pearson相关分析结果显示,血清ANGPTL4、HSP70与HOMA-IR呈负相关(r值分别为-0.733、-0.758,P<0.001),IL-34和HOMA-IR呈正相关(r=0.705,P<0.001)。治疗后,超重/肥胖T2DM组和体重正常T2DM组血清ANGPTL4和HSP70均明显升高,血清IL-34和HOMA-IR明显降低;且相对于超重/肥胖T2DM组,体重正常T2DM组血清ANGPTL4和HSP70升高更显著(P<0.05),血清IL-34和HOMA-IR降低更显著(P<0.05)。结论 超重/肥胖合并T2DM患者ANGPTL4、HSP70和IL-34与胰岛素抵抗显著相关,或可作为超重/肥胖合并T2DM的疗效监测指标。

Hepatitis C virus infection and insulin resistance

Approximately 170 million people worldwide are chronically infected with hepatitis C virus(HCV).Chronic HCV infection is the leading cause for the development of liver fibrosis,cirrhosis,hepatocellular carcinoma(HCC)and is the primary cause for liver transplantation in the western world.Insulin resistance is one of the pathological features in patients with HCV infection and often leads to development of typeⅡdiabetes.Insulin resistance plays an important role in the development of various complications associated with HCV infection.Recent evidence indicates that HCV associated insulin resistance may result in hepatic fibrosis,steatosis,HCC and resistance to anti-viral treatment.Thus,HCV associated insulin resistance is a therapeutic target at any stage of HCV infection.HCV modulates normal cellular gene expression and interferes with the insulin signaling pathway.Various mechanisms have been proposed in regard to HCV mediated insulin resistance,involving up regulation of inflammatory cytokines,like tumor necrosis factor-α,phosphorylation of insulin-receptor substrate-1,Akt,up-regulation of gluconeogenic genes like glucose 6 phosphatase,phosphoenolpyruvate carboxykinase 2,and accumulation of lipid droplets.In this review,we summarize the available information on how HCV infection interferes with insulin signaling pathways resulting in insulin resistance.

人吻素1、脂肪酸结合蛋白质4与糖脂代谢指标的相关性分析及其对妊娠糖尿病的早期诊断价值

目的探讨人吻素1、脂肪酸结合蛋白质4(FABP4)与糖脂代谢指标的相关性及其对妊娠糖尿病(GDM)的早期诊断价值。方法选取2018年1月至2022年1月在河北大学附属医院产科门诊建卡的496例孕妇作为研究对象,根据是否发生GDM分为GDM组和正常组。比较两组孕妇的临床资料。采用Pearson相关分析GDM患者人吻素1、FABP4水平与糖脂代谢指标的相关性。采用多因素Logistic回归分析孕妇发生GDM的危险因素。绘制受试者工作特征(ROC)曲线分析人吻素1、FABP4单独及联合检测对GDM的诊断价值。结果两组孕妇孕前体质量指数(BMI)、孕24周增长体质量、稳态模型胰岛素抵抗指数(HOMA-IR)、稳态模型胰岛β细胞功能指数(HOMA-β)、空腹血糖(FBG)、口服葡萄糖耐量试验(OGTT)1 h血糖(1 hPG)、OGTT 2 h血糖(2 hPG)、糖化血红蛋白(HbA1c)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、空腹胰岛素(FINS)、人吻素1、FABP4水平比较,差异均有统计学意义(P<0.05)。Pearson相关分析结果显示,GDM孕妇人吻素1水平与孕前BMI、HOMA-IR、FBG、OGTT 1 hPG、OGTT 2 hPG、HbA1c、TG、FINS水平均呈正相关(P<0.05),与HOMA-β呈负相关(P<0.05);GDM孕妇FABP4水平与孕24周增长体质量、HOMA-IR、TG、LDL-C、FINS水平均呈正相关(P<0.05),与高密度脂蛋白胆固醇(HDL-C)水平、HOMA-β均呈负相关(P<0.05)。多因素Logistic回归分析结果显示,孕24周增长体质量、HOMA-IR、HOMA-β、FBG、OGTT 1 hPG、OGTT 2 hPG、HbA1c、TG、FINS、人吻素1、FABP4水平升高是孕妇发生GDM的独立危险因素(P<0.05)。ROC曲线分析结果显示,人吻素1、FABP4联合诊断GDM的曲线下面积(AUC)为0.865,高于人吻素1、FABP4单独诊断GDM的AUC(Z=4.563、5.681,P<0.05)。结论人吻素1、FABP4对GDM的早期诊断具有重要意义,2项指标联合检测能够有效提高GDM的诊断率。

肝特异性Rbp4基因敲除小鼠的建立及糖代谢特征分析

目的 建立肝特异性Rbp4基因敲除小鼠模型,并初步探索肝特异性Rbp4基因缺失对糖代谢的影响。方法 利用Cre-LoxP技术,使用C57/BL6J小鼠和Alb-Cre小鼠构建肝特异性Rbp4基因敲除小鼠模型。利用PCR及琼脂糖凝胶电泳鉴定小鼠基因型。选取10只18周龄C57/BL6J雄性小鼠为野生对照组(WT),10只同周龄flox纯合且Alb-Cre阴性小鼠为实验对照组(Rbp4~(flox/flox):Cre~-),10只同周龄flox纯合且Alb-Cre阳性小鼠为实验组(Rbp4~(flox/flox):Cre~+)。分别利用Western Blot及qRT-PCR验证小鼠肝中RBP4蛋白及Rbp4 mRNA表达水平。利用qRT-PCR检测其他组织中Rbp4 mRNA表达水平。采用苏木素-伊红(HE)染色观察肝组织形态。利用血糖仪检测小鼠尾静脉血液标本血糖值,进行葡萄糖耐量及胰岛素耐量实验。利用qRT-PCR检测肝糖代谢基因磷酸烯醇丙酮酸羧化酶(Pepck)和葡萄糖-6-磷酸酶(G6pase)表达水平。结果 成功繁育并鉴定出肝特异性Rbp4基因敲除小鼠。Rbp4~(flox/flox):Cre~+组小鼠肝中RBP4蛋白表达显著减少(P<0.05),Rbp4 mRNA表达显著减少(P<0.05)。三组小鼠脂肪、肾、胰、脾、心脏和肌肉组织中Rbp4 mRNA的相对表达量差异无显著性(P>0.05)。HE染色、葡萄糖耐量及胰岛素耐量实验结果表明肝特异性Rbp4基因敲除对肝组织形态、葡萄糖耐量及胰岛素耐量无显著影响(P>0.05)。三组小鼠肝中Pepck mRNA表达差异具有显著性(P<0.05),两两比较显示,Rbp4~(flox/flox):Cre~+组小鼠肝中Pepck mRNA相对表达量较Rbp4~(flox/flox):Cre~-组小鼠降低(P<0.05)。三组小鼠肝中G6pase mRNA表达差异无显著性(P>0.05)。结论 成功构建了肝特异性Rbp4基因敲除小鼠模型,基因缺失可抑制小鼠肝Pepck mRNA表达,为进一步探索该基因在小鼠糖代谢中的作用提供依据。

Involvement of Cbl-b-mediated macrophage inactivation in insulin resistance

Aging and overnutrition cause obesity in rodents and humans. It is well-known that obesity causes various diseases by producing insulin resistance(IR). Macrophages infiltrate the adipose tissue(AT) of obese individuals and cause chronic low-level inflammation associated with IR. Macrophage infiltration is regulated by the chemokines that are released from hypertrophied adipocytes and the immune cells in AT. Saturated fatty acids are recognized by toll-like receptor 4(TLR4) and induce inflammatory responses in AT macrophages(ATMs). The inflammatory cytokines that are released from activated ATMs promote IR in peripheral organs, such as the liver, skeletal muscle and AT. Therefore, ATM activation is a therapeutic target for IR in obesity. The ubiquitin ligase Casitas b-lineage lymphoma-b(Cbl-b) appears to potently suppress macrophage migration and activation. Cbl-b is highly expressed in leukocytes and negatively regulates signals associated with migration and activation. Cbl-b deficiency enhances ATM accumulation and IR in aging- and diet-induced obese mice. Cbl-b inhibits migration-related signals and SFA-induced TLR4 signaling in ATMs. Thus, targeting Cbl-b may be a potential therapeutic strategy to reduce the IR induced by ATM activation. In this review, we summarize the regulatory functions of Cbl-b in ATMs.

Effect of iron supplementation on glucose transporter 4 expression in adipose tissue and skeletal muscle of pregnant rats

Objective: The main goal of the present study was to investigate the effect of iron supplementation on glucose transporter 4 expressions in adipose tissue and skeletal muscle in female rats during pregnancy. Methods: Twenty-four pregnant Sprague-Dawley rats were randomly divided into 2 groups: a control group with a standard diet (containing iron 150 mg/kg) and an iron-supplementation group with a high-iron diet (containing iron 700 mg/kg) from day 0 to day 21 of pregnancy. Intraperitoneal glucose tolerance test was performed on gestational day 19. On gestational day 21, all of the pregnant rats from each group were sacrificed. The mean neonatal weights were measured and samples of maternal intraabdominal adipose tissue and skeletal muscle were taken to measure the expression of Glucose Transporter 4 (GLUT4) mRNA and protein. Results: Glucose tolerance decreased significantly in the iron supplementation group compared to the control group. The mean neonatal weights in the iron supplementation group were higher than that in the control group. Levels of GLUT4 mRNA in the adipose tissue were reduced by the administrations of high-iron diet. The skeletal muscle GLUT4 mRNA levels were not changed significantly by iron supplementation. Expression of GLUT4 protein both in the adipose tissue and skeletal muscle reduced significantly. Conclusion: These results suggest that iron supplementation during pregnancy would increase neonatal weights and could decrease maternal glucose tolerance by interfering GLUT4 expression in adipose tissue and skeletal muscle of rats.

Photoactivation of GLUT4 translocation promotes glucose uptake via PI3-K/Akt2 signaling in 3T3-L1 adipocytes

Insulin resistance is a hallmark of the metabolic syndrome and type 2 diabetes.Dysfunction of PI-3K/Akt signaling was involved in insulin resistance.Glucose transporter 4(GLUT4)is a keyfactor for glucose uptake in muscle and adipose tissues,which is closely regulated by Pi-3K/Aktsignaling in response to insulin treatment.Low-power laser irradiation(LPLI)has been shown toregulate various physiological processes and induce the synthesis or release of multiple moleculessuch as growth factors,which(especially red and near infrared light)is mainly through theactivation of mitochondrial respiratory chain and the initiation of intracellular signaling path-ways.Nevertheless,it is unclear whether LPLI could promote glucose uptake through activationof PI-3K/Akt/GLUT4 signaling in 3T3L-1 adipocytes.In this study,we investigated how LPLIpromoted glucose uptake through activation of PI-3K/Akt/GLUT4 signaling path way.Here,we showed that GLUT4 was localized to the Golgi apparatus and translocated from cytoplasm tocytomembrane upon LPLI treatment in 3T3L-1 adipocytes,which enhanced glucose uptake.Moreover,we found that glucose uptake was mediated by the PI3-K/Akt2 signaling,but notAkt1 upon LPLI treatment with Akt isoforms gene silence and PI3-K/Akt inhibitors.Collec-tively,our results indicate that PI3-K/Akt2/GLUT4 signaling act as the key regulators forimprovement of glucose uptake under LPLI treatment in 3T3L-i adipocytes.More importantly,our findings suggest that activation of PI3-K/Akt2/GLUT4 signaling by LPLI may provideguidance in practical applications for promotion of glucose uptake in insulin-resistant adiposetissue.

A Potential Role for GLUT4 in Predicting Sepsis in Critically Ill Children

Background: This study investigated serum Glucose transporter (GLUT) 4 levels and examined the relationship between serum GLUT4 levels and sepsis in critically ill children. Methods: This was a retrospective study of 77 critically ill children and 33 non-diabetic healthy children (controls) who were admitted between 07/2015 and 05/2016. Patient data, clinical information, and blood samples were collected on admission, alongside a large number of laboratory parameters that were routinely assessed. Critically ill patients were divided into sepsis and non-sepsis/systemic inflammatory response syndrome (SIRS). Serum GLUT4 was measured using western blotting and enzyme-linked immunosorbent assays. Insulin resistance indexes, clinical data, laboratory parameters, and inflammatory cytokines were assessed. Results: GLUT4 serum levels were higher in critically ill children than in healthy children (90.5 vs. 30.3 μg/L, P 0.05). Compared to healthy children, hyperglycemic patients (n = 48) had elevated GLUT4 serum levels (30.3 vs. 103.7 g/L, P Conclusions: GLUT4 serum levels might be significantly increased in critically ill children compared with healthy children, particularly those in septic shock. Serum GLUT4 could predict disease severity.

The expression of glucose transporter 4 in endometrium of polycystic ovary syndrome women and its change after metformin treatment

Objective:To investigate the protein and messenger RNA expression of glucose transporter 4 in endometrium of women with polycystic ovary syndrome(PCOS),and to evaluate its change after three months treatment of metformin.Methods:Twenty-two patients with polycystic ovary syndrome(group A)and six non-PCOS infertile women(group B)were recruited in our hospital.The consent form was obtained from each patient.Endometrium and blood samples were obtained during the proliferative phase of the menstrual cycle.Reverse transcriptase-polymerase chain reaction(RT-PCR)and immunohistochemical method were applied to detect the expression of glucose transporter 4(GLUT4)in endometrium.All PCOS patients received monotherapy of metformin after endometrium biopsy.Seven un-conceived patients(group A1)from group A who completed three months of metformin treatment were selected to perform the second time biopsy during proliferative phase.The expression of GLUT4 were remeasured as well.Results:There were no significant differences of the levels of E2,P and endometrium thickness on the biopsy day between group A and group B.But the basal levels of LH,T,LH/FSH ratio,and the ovarian volume were significantly higher in group A as compared with group B(P<0.001).The expression of GLUT4 in group A was significantly lower than that of group B(1.05±0.13 vs 1.50±0.21,P<0.001).In group A1,the expression of GLUT4 in endometrium were changed from 1.08±0.08 to 1.27±0.16 before and after treatment(P<0.05).The results of immunohistochemical staining of GLUT4 in endometrium were coincident with the results of RT-PCR.The fast insulin level and the insulin sensitivity index were also improved obviously after three months of metformin therapy(P<0.05).Conclusions:Insulin-resistance status was proved existing in endometrium of PCOS women;A significant improvement of GLUT4 expression was observed in endometrium after metformin treatment,supporting that metformin can relief insulin-resistant status of the endometrium in PCOS patients.

miR-93-5p对胰岛素抵抗细胞模型中HGF、GLUT4表达及GLUT4分布的影响

目的探讨miR-93-5p对胰岛素抵抗细胞模型中肝细胞生长因子(hepatocyte growth factor,HGF)、葡萄糖转运蛋白4(glucose transporter 4,GLUT4)表达及GLUT4分布的影响。方法将细胞分为对照组、模型组、miR-93-5p inhibitor组、inhibitor-NC组、miR-93-5p mimics组和mimics-NC组。对照组细胞正常培养,模型组构建胰岛素抵抗细胞模型,其余组分别转染miR-93-5p inhibitor、inhibitor-NC、miR-93-5p mimics、mimics-NC,转染完成后构建胰岛素抵抗模型。CCK-8检测细胞存活率;试剂盒检测细胞上清液中葡萄糖含量,计算葡萄糖消耗量;qPCR检测miR-93-5p、HGF、GLUT4的mRNA表达水平;Western blot检测HGF、GLUT4蛋白表达水平;免疫荧光检测GLUT4的表达和分布。结果与对照组相比,模型组细胞存活率、葡萄糖消耗量、HGF、GLUT4 mRNA和蛋白表达水平均显著降低(均P<0.01),miR-93-5p水平显著升高(P<0.01),GLUT4膜分布减少。与模型组相比,miR-93-5p inhibitor组细胞存活率、葡萄糖消耗量、HGF、GLUT4 mRNA和蛋白表达水平均显著升高(均P<0.05),miR-93-5p水平显著降低(P<0.01),GLUT4膜分布增多;mimics组结果相反。结论miR-93-5p能够抑制胰岛素抵抗细胞模型中HGF和GLUT4的表达,并减少GLUT4的膜分布,具有促进胰岛素抵抗的功能。

Pandanus amaryllifolius leaf extract increases insulin sensitivity in high-fat diet-induced obese mice

Objective: To examine the effect of Pandanus amaryllifolius(P. amaryllifolius) leaf extract on the insulin resistance state in obese ICR mice.Methods: Obesity was induced in mice fed with high-fat diet(45% fat) for 12 weeks. After the first six weeks on the diet, the obese mice were administered with the water extract of P. amaryllifolius leaf at 125 and 250 mg/kg/day, respectively for another six weeks. At the5 th week of treatment, oral glucose tolerance test was conducted. After six weeks of treatment, the levels of blood glucose, serum insulin, leptin, adiponectin, and lipid profiles were determined. The liver, muscle and epididymal fat tissues were removed for measuring the biochemical parameters and protein expression, as well as histological examination.Results: Six weeks of treatment with P. amaryllifolius led to a significant reduction in the blood glucose level as well as improvement in the insulin resistance. P. amaryllifolius also increased the liver glycogen storage and serum adiponectin and decreased the serum leptin levels. A reduction in the serum and hepatic triglyceride, and non-esterified fatty acid levels was also observed. The histological examination showed that the obese mice treated with P. amaryllifolius reduced the lipid droplet in liver tissue and adipocyte size in epididymal fat tissue. The treatment also increased the protein expression of glucose transporter 4 in the muscle and fat tissues.Conclusions: The treatment with P. amaryllifolius could decrease several parameters of impaired glucose and lipid metabolism. To the best of our knowledge, this is the first report on the role of P. amaryllifolius leaf extract in alleviating the insulin dysfunction in obesity state.

SH2B1 regulation of energy balance, body weight, and glucose metabolism

The Src homology 2B(SH2B)family members(SH2B1,SH2B2 and SH2B3)are adaptor signaling proteins containing characteristic SH2 and PH domains.SH2B1(also called SH2-B and PSM)and SH2B2(also called APS)are able to form homo-or hetero-dimers via their N-terminal dimerization domains.Their C-terminal SH2 domains bind to tyrosyl phosphorylated proteins,including Janus kinase 2(JAK2),TrkA,insulin receptors,insulin-like growth factor-1 receptors,insulin receptor substrate-1(IRS1),and IRS2.SH2B1 enhances leptin signaling by both stimulating JAK2 activity and assembling a JAK2/IRS1/2 signaling complex.SH2B1 promotes insulin signaling by both enhancing insulin receptor catalytic activity and protecting against dephosphorylation of IRS proteins.Accordingly,genetic deletion of SH2B1 results in severe leptin resistance,insulin resistance,hyperphagia,obesity,and type 2 diabetes in mice.Neuronspecific overexpression of SH2B1βtransgenes protects against diet-induced obesity and insulin resistance.SH2B1 in pancreaticβcells promotesβcell expansion and insulin secretion to counteract insulin resistance in obesity.Moreover,numerous SH2B1 mutations are genetically linked to leptin resistance,insulin resistance,obesity,and type 2 diabetes in humans.Unlike SH2B1,SH2B2 and SH2B3 are not required for the maintenance of normal energy and glucose homeostasis.The metabolic function of the SH2B family is conserved from insects to humans.

Obesity and type 2 diabetes

Obesity and type 2 diabetes (T2DM) are public health problems, with health consequences and economic costs that have raised concern worldwide. The increase in the prevalence of diabetes parallels that of obesity. Some experts call this dual epidemic ‘diabesity’ Elevated body mass index (BMI) and waist circumference (WC) were significantly associated T2DM. One consequence of obesity is an increased risk of developing T2DM. There is evidence that the prenatal, early childhood, and adolescent periods are critical in the development of obesity. Most obese individuals have elevated plasma levels of free fatty acids (FFA), which are known to cause peripheral (muscle) insulin resistance. Weight loss either with lifestyle modification, pharmacotherapy or bariatric surgery improves glycemic control and metabolic parameters that are related to cardiovascular disease. Pharmacotherapy for glycemic control with metformin or GLP-1 agonists and DPP-4 inhibitors help in weight reduction.

TBC1结构域家族成员4与心肌胰岛素抵抗的研究进展

体外循环是心血管外科开胸心内直视手术必需的重要辅助手段,而体外循环术后常见的严重并发症是心肌缺血再灌注损伤(MIRI)。MIRI的发生机制复杂,心肌胰岛素抵抗(IR)是其重要发病机制之一,其中心肌细胞葡萄糖转运蛋白4(GLUT4)的表达和转位异常是心肌IR发生的主要原因。TBC1结构域家族成员4是TBC家族蛋白的重要成员,可通过Rab蛋白调控GLUT4的囊泡转运,是磷脂酰肌醇-3-激酶/蛋白激酶B信号通路和AMP活化的蛋白激酶信号通路重要的下游靶点,与IR的发生密切相关。

孕早期血清脂肪因子CTRP6与妊娠糖尿病的关系

目的研究孕早期妇女血清补体C1q/肿瘤坏死因子相关蛋白6(C1q/tumor necrosis factor-related protein 6,CTRP6)的表达水平,探讨其与妊娠糖尿病(gestational diabetes mellitus,GDM)的关系。方法前瞻性连续选取2021年3月至2022年3月在郑州大学第二附属医院门诊产检的孕10~13周孕妇,收集孕妇的年龄、身高、体质量、末次月经时间,检测孕早期总胆固醇(total cholesterol,TC)、三酰甘油(triglyceride,TG)、高密度脂蛋白(high density lipoprotein,HDL)、低密度脂蛋白(low density lipoprotein,LDL)、空腹血糖(fasting plasma glucose,FPG)、糖化血红蛋白(glycosylated hemoglobin,HbA1c)、空腹胰岛素(fasting insulin,FINS)、CTRP6水平,计算孕前体质量指数(body mass index,BMI)、基线BMI、产前BMI和胰岛素抵抗指数(亦称胰岛素抵抗的稳态模型评估,homeostatic model assessment of insulin resistance,HOMA-IR)。所有孕妇均于孕24~28周行75g口服葡萄糖耐量试验,根据试验结果分为GDM组和糖耐量正常(normal glucose tolerance,NGT)组。比较两组孕妇孕早期的临床资料及实验室指标,分析孕早期血清CTRP6与各指标的相关性及其与GDM的关系。结果共纳入孕妇213例,完整随访203例,其中52例孕妇被诊断为GDM,GDM发病率25.62%。GDM组孕妇的孕早期血清CTRP6、年龄、孕前BMI、基线BMI、产前BMI、TC、LDL、FPG、HbA1c、FINS、HOMA-IR均较NGT组升高,差异有统计学意义(P<0.05)。孕早期CTRP6与年龄、孕前BMI、基线BMI、产前BMI、TG、LDL、FPG、HbA1c、FINS、HOMA-IR呈正相关,与HDL呈负相关(P<0.05)。校正年龄、BMI、糖脂代谢指标及HOMA-IR后,孕早期CTRP6为GDM发病的独立影响因素。结论孕早期血清CTRP6升高与GDM相关,是GDM的独立危险因素。

心外膜脂肪组织与代谢综合征相关性的研究进展

代谢综合征是一组以胰岛素抵抗、超重/肥胖为核心,合并糖脂代谢异常、高血压等的代谢失衡综合征。心外膜脂肪组织作为一种特殊的脂肪组织,既具备脂肪储能、机械保护的生理特性;又具有高分泌活性,能够释放多种抗炎/炎症因子,调节游离脂肪酸的摄取/释放,其代谢稳态在代谢综合征的进程中发挥着重要的作用。心外膜脂肪组织与代谢综合征各组分的相关性研究也不断取得新进展,主要从异位脂肪堆积、游离脂肪酸超载、脂肪低度炎症、氧化应激方面探讨影响代谢综合征的核心机制,通过改善生活方式、药物干预、手术干预等措施均可减少心外膜脂肪组织体积,进而改善代谢综合征,减少心血管事件。因此本文将心外膜脂肪组织与代谢综合征的相关性、影响机制及治疗策略研究进展进行综述。

葡萄糖依赖性促胰岛素多肽与多囊卵巢综合征相关性的研究进展

多囊卵巢综合征(Polycystic ovary syndrome,PCOS)作为育龄期女性最常见的生殖内分泌疾病之一,其发病与胰岛素抵抗(Insulin resistance,IR)、慢性炎症、肥胖以及高雄激素血症等密切相关,具体发病机制尚不明确。葡萄糖依赖性促胰岛素多肽(Glucose-dependent insulinotropic polypeptide,GIP)作为一种参与血糖调控的胃肠激素,与影响PCOS发病的因素密切相关,其与受体结合后,通过参与糖脂代谢、性激素代谢以及影响机体炎症反应而改善IR,为探索PCOS的发病机制提供新的思路。本文探讨了GIP与PCOS的相关性。