Insulin Resistance And Pancreatic Beta-cell Function Of Gestational Diabetes Mellitus In Relation To Changes Of FGF21and Nesfatin-1

Objective1.To observe the changes of insulin resistance and pancreatic beta-cell function afteroral glucose tolerance test（OGTT）in patients of gestational diabetes mellitus（GDM）between24-28gestational weeks.2.To investigate the differences of serum FGF21and Nesfatin-1in patients ofgestational diabetes mellitus（GDM）and the analysis of correlations between them andinsulin resistance and pancreatic beta-cell function.Methods1. A75-g oral glucose tolerance test(OGTT) was performed among90pregnant womenbetween24to28gestational weeks who were matched for gestational age,prepregnancybody mass index(BMI) and increased BMI during pregnancy. According to the criteriaof American Diabetes Association and fasting plasma glucose(FPG) levels, the studysubjects were divided into three groups:normal glucose tolerance(NGT, n=45), GDM1group (5.1mmol/L≦F PG＜7.0mmol/L，n=27) and GDM2group (FPG≧7.0mmol/L，n=18).2.Collected names, ages, family history, dietary habit, prepregnancy weight, number ofpregnancies, history of fertility,such basic information of all subjects by questionnairesurvey. Anthropometric measurements including height,weight were surveyed tocalculate BMI.3. All subjects were experienced an oral glucose tolerence test after8-10hoursovernight fasted. Venous blood samples were obtained at0min,30min,1h,2h. Plasmaglucose of different time points were soon measured by the glucose-oxidase method,insulin and C peptide were soon measured by the chemiluminescence method. Serum FGF21and Nesfatin-1concentrations were measured by enzyme-linked immunosorbentassay.The homeostasis model assessment of insulin resistance(HOMA-IR), the HOMAof β-cell insulin secretion(HOMA-β), a ratio of the area under the insulin curve to thearea under the plasma glucose curve (AUCINS/PG) and early insulin secretion index(△I30/△G30)were calculated.Results1.Comparisons of clinical parameters：Compared with NGT group, patients with GDM1and GDM2had increased levels of FPG,30min PG,1hPG,2hPG, FINS, HOMA-IR,PGAUC（P<0.01）, while, had decreased levels of HOMA-β(P<0.01,P<0.05).TheINSAUC/PGAUCand△I30/△G30in GDM2group were also lower than those in NGTgroup(P<0.01).The patients in GDM2group had higher FPG,30min PG,1hPG,2hPG,HOMA-IR and PGAUC(P<0.01),whereas lower HOMA-β，INSAUC/PGAUCand△I30/△G30when compared with patients in GDM1group(P<0.01,P<0.05).2.Comparisons of FGF21and Nesfatin-1：concentrations of FGF21and Nesfatin-1were significantly higher in patients with GDM1and GDM2than in controls(P<0.01),and GDM2group was also higher than GDM1group(P<0.01,P<0.05). FGF21was positively correlated with prepregnancy BMI, FPG,30minPG,1hPG,2hPG,HOMA-IR and PGAUC(P<0.01), but negatively with HOMA-β(P<0.05). Nesfatin-1was positively correlated with FPG,30min PG,1hPG,2hPG, HOMA-IR andPGAUC(P<0.01,P<0.05), but negatively correlated with HOMA-β(P<0.05).Conclusions1.The severity of FPG in gestational diabetes mellitus patients may reflect the degree oftheir insulin resistance and their bete cell dysfunction.2. The study suggests that FGF21and Nesfatin-1are higher in GDM patients，whichmay play a role in the pathogenesis of GDM.