The Correlation Between Serum Irisin And Insulin Resistance In Patients With Gestational Diabetes Mellitus And The Effect Of Body Mass Index On Serum Irisin

Objective1.To observe the changes of insulin resistance and pancreatic beta-cell function in patients of gestational diabetes mellitus(GDM) between 24-28 gestational weeks.2.To investigate the differences of serum Irisin in patients of gestational diabetes mellitus(GDM)and the analysis of correlations between them and insulin resistance and pancreatic beta-cell function.3.To observe the relationship between body mass index and insulin resistance,pancreatic beta-cell function as well as levels of blood lipid.4. To test the changes of serum Irisin levels in non diabetic pregnant women and analyze the relationship with body mass index.Methods1.The study collected the information of pregnant women between 24 to 32 gestational weeks who had performed 75-g oral glucose tolerance test(OGTT).According to OGTT and the criteria of American Diabetes Association, We select normal glucose tolerance(NGT, n=50) and gestational diabetes mellitus group(GDM,n=50) from the data. Meanwhile, according to body mass index(BMI), GDM group were divided into diabetes and overweight group(GDM+OWG,n=17) as well as diabetes and non overweight group(GDM+NOW, n=33); Similarly, NGT group were divided into simple overweight group(OWG,n=15) as well as control group(CON,n=35).2. The questionnaire survey record names, ages, dietary habit, number of pregnancies, time of the last menstrual period,weight before pregnancy, family history, history of fertility, such general information of all subjects.The height(m) and weight(kg) of all subjects were measured.The prepregnancy body mass index(BMI) and increased BMI during pregnancy were calculated.3.All subjects were underwent an OGTT after overnight fasted for 8-10 hours.Venous blood samples were obtained at 0 min, 1h, 2h. Oxide electrode method was used to detect plasma glucose of different time points. Chemiluminescence method was used to measure insulin and C-peptide. Enzyme-linked immunosorbent assay was used to measure fasting serum Irisin levels. The figures of total cholesterol(TC),triglyceride(TG), high density lipoprotein(HDL-C), very low density lipoprotein(VLDL) and low density lipoprotein(LDL-C) were measured by the collected fasting blood. The homeostasis model assessment of insulin resistance index(HOMA-IR) and pancreatic island beta cell function(HOMA-β) were calculated.Results1.Comparisons of clinical parameters:Compared with NGT group, patients with GDM had increased levels of FPG, 1 h PG, 2 h PG, FINS, C-peptide, HOMA-IR, TG, TC,LDL-C and VLDL-C(P<0.01,P<0.05), while had decreased levels of HOMA- β(P<0.05).The levels of BMI,C-peptide,TG and VLDL-C in GDM+OWG are higher than patients in GDM+NOW(P<0.05). Compared with CON group,patients in GDM+OWG and GDM+NOW had higher levels of increased levels of FPG, 1 h PG, 2 h PG, FINS,C-peptide and HOMA-IR, meanwhile, the levels of TG and VLDL-C in GDM+OWG is higher than CON(P<0.05).Compared with CON group, patients in OWG had increased levels of BMI,FINS and HOMA-IR,but decreased levels of HDL-C(P<0.05).2.Comparisons of Irisin: concentrations of serum Irisin were significantly lower in patients with GDM than in NGT(P<0.05).Levels of Irisin in GDM+OWG are significantly lower than GDM+NOW(P<0.05).Compared with control group, patients in diabetes and overweight group, patients with simple GDM and patients with simple overweight all had lower levels of serum Irisin. According to Pearson product moment correlation analysis, concentrations of serum Irisin in GDM was positively correlated with HOMA-βand HDL-C,but negatively with prepregnancy BMI, FPG, 1 h PG, 2 h PG, C-peptide,,HOMA-IR, TG, and VLDL-C(P<0.05).Concentrations of serum Irisin in GDM+NOW and OWG were correlated with prepregnancy BMI.Conclusions1.With the increase of FPG, insulin resistance increased and pancreatic beta-cell function decreased. The level of FPG may affect the degree of insulin resistance and their beta cell dysfunction in gestational diabetes mellitus patients.2.The study suggests that serum Irisin was lower in GDM patients,which may play a role in the pathogenesis of GDM.3. Insulin resistance raised with the increase of BMI in non diabetic pregnant women.To a certain extent,the level of BMI may reflect the degree of insulin resistance.4 The level of fasting serum Irisin was decreased in overweight and obese pregnant women. BMI may had an effect on the standard of serum Irisin.