Studies On Insulin Resistance In Gestational Diabetes Mellitus Patients

Gestational diabetes mellitus(GDM) refers to the sugar metabolism unusual disease which is occurred or initially found in the gestation period,and therefore is being paid high attention by domestic and foreign obstetricians day by day due to its serious harm to mother and baby health.Although the pathogenesis of this disease is still at studies,at present,the insulin resistance is considered to play the vital role in the GDM pathogenesis.In the mammal,a series of cytokines including leptin, adiponectin,free fatty acids(FFA) and so on,could be secreted from the fatty tissue to participate in the insulin regulation of biological effects in target tissues,therefore possibly are playing the vital roles in the insulin resistance.Here in this article,the relationships between insulin resistance and changes of sera adiponectin,leptin,and free fatty acids in gestational diabetes mellitus patients were discussed. PartⅠLeptin resistance and gestational diabetes mellitusObjective To detect the leptin and insulin levels in the sera of pregnant women with gestational diabetes mellitus(GDM),in order to explore the relationships between leptin or insulin resistance(IR) and the GDM patients,and to study the insulin resistance mechanism in GDM patients.Methods 40 cases of GDM patients were selected,60 cases of the normal pregnant women were selected as control,using the method of radio-immunology, and we detected the levels of leptin,serum glucose,insulin and C-peptide of the pregnant women under fasting condition in experimental and control groups.IR index was calculated with homeostasis model assessment(HOMA),and insulin resistance (IR) was evaluated.Results(1) The serum levels of leptin under fasting condition in GDM and control groups were(15.0±4.1) ng/ml and(13.9±3.4).ng/ml,showing no significant difference(P＞0.05).The HOMA-IR of GDM and control groups were(6.41±2.58) and(4.52±2.48) respectively,the difference showed the statistical significance(P＜0.01);(2) The levels of serum glucose,insulin,C peptide/insulin in GDM group were(5.8±1.2) mmol/L,(24.7±6.7) mU/L,(26.9±6.0) respectively,of which in control group were(5.2±1.0) mmol/L,(19.0±8.9) mU/L,(36.5±15.4) respectively, showing the significant difference(P＜0.01);(3) under the condition of the same BMI,the leptin levels in GDM group were higher,But showing no statistical significance(P＞0.05);(4) The serum levels of leptin under fasting condition in BMI≥25 and BMI＜25 were(15.3±4.0) ng/ml and(13.4±3.1) ng/ml,showing significant difference(P＜0.05);(5) The levels of leptin were positively correlated with HOMA-IR(r=0.292,P＜0.05),Ins(r=0.375,P＜0.01) and BMI before pregnancy(r=0.297,P＜0.05) in control group.Conclusion The levels of insulin were significantly increased under fasting condition in GDM patients,indicating the phenomena of insulin resistance.The levels of leptin were increased under fasting condition in GDM patients,perhaps indicating the phenomena of leptin resistance.There might be mutual regulation between them. The connections among leptin,insulin resistance,obesity and GDM were to be further studied. PartⅡStudies on the relationships between insulin resistance and sera adiponectin,free fatty acids in gestational diabetes mellitus patientsObjective To detect the levels of adiponectin,free fatty acids(FFA) and insulin in the sera of pregnant women with gestational diabetes mellitus(GDM),in order to explore whether the GDM patients have the low adiponectin and the high free fatty acids(FFA) levels,and to discuss the relationship between these levels and insulin resistance(IR),and to study the pathogenesis of insulin resistance in GDM patients.Methods 40 cases of GDM patients were selected,and divided into two experimental groups according to the BMI,in which 20 cases with BMI＜25,20 cases with BMI≥25;60 cases of the normal pregnant women were selected as control, and also divided into two groups,in which 30 cases with BMI＜25,30 cases with BMI≥25.Using the method of radio-immunology,we detected the levels of adiponectin,insulin and C-peptide of the pregnant women under fasting condition in experimental and control groups.FFA,serum glucose,triglyceride(TG) and cholesterol(TC) were detected by method of enzymology.High-density lipoprote in cholesterol(HDL-C) and low-density lipoprote in cholesterol(LDL-C) were also detected by the method of selective suppression.IR index was calculated with homeostasis model assessment(HOMA),and the insulin resistance(HOMA-IR) was evaluated. Results(1) The serum levels of adiponectin and FFA under fasting condition in GDM were(1.28±0.60) ug/ml and(990±541) umol/L respectively,and in control groups,the levels were(1.59±0.60) ug/ml and(802±284) umol/L respectively, showing the significant difference(P＜0.05).The HOMA-IR of GDM and control groups were(6.41±2.58) and(4.52±2.48) respectively,the difference showed the statistical significance(P＜0.01).(2) The levels of serum glucose,insulin,C peptide/insulin in GDM group were(5.8±1.2) mmol/L,(24.7±6.7) mU/L,(26.9±6.0) respectively,of which in control group were(5.2±1.0) mmol/L,(19.0±8.9) mU/L,(36.5±15.4) respectively,showing the significant difference(P＜0.01).(3) The levels of cholesterol and triglyceride in GDM group were(5.26±1.01) mmol/L and (3.17±1.30) mmol/L respectively,of which in control group were(4.55±1.17) mmol/L and(2.66±1.02) mmol/L respectively,showing the significant difference(P＜0.05).There was no difference(P＞0.05) between groups of HDL-C and LDL-C. (4) The adiponectin levels in GDM group(1.30±0.51 ug/ml)were significantly lower than those in control group(1.72±0.50 ug/ml)under the condition of BMI＜25,where as the levels of adiponectin in experimental and control groups had no difference under the condition of BMI≥25.(5) The levels of adiponectin were negatively correlated with FFA(r=-0.245,P＜0.05) and HOMA-IR(r=-0.161,P＜0.05). However,the levels of FFA were positively correlated with HOMA-IR(r=0.240,P＜0.05).Discussion There were low levels of adiponectin and high levels of FFA under fasting condition in GDM patients,and the low levels of adiponectin only existed in GDM patients with normal body weight,excepting the factor of body fat.There was symptom of high lipemia in GDM patients,and in obesity group,the blood fats levels of GDM patients were still higher than those of control.Adiponectin was negatively correlated with insulin resistance,and FFA was positively correlated with insulin resistance.There is not only the unusual sugar metabolism,but also the unusual lipin metabolism in GDM patients.The connections among adiponectin,FFA,insulin resistance,obesity and GDM were to be further studied.