The Study Of Free Fatty Acids And Maleic Dialdehyde And Their Related Factors In Normal Glucose Tolerance First-Degree Relatives Of Type 2 Diabetes Mellitus

Background and Purpose:To investigate the changes and the roles of the free fatty acids(FFA) and maleic dialdehyde(MDA) in type 2 diabetes mellitus and their normoglycemic first-degree relatives and the influence of heretic factors in lipid metabolism. And to study the relationship between FFA and insulin resistance and the function of islet beta cell. And to analyze the changes of their antioxidant ability. All in all, our aim is to search new targets for preventing type 2 diabetes mellitus.Objectives and Method:35 type 2 diabetic pedigrees were selected randomly from the endocrine department and outpatient service of Qi Lu Hospital of Shan Dong University. 38 type 2 diabetic patients served as diabetes group and 56 normoglycemic first-degree relatives as observation group and 35 healthy controls without diabetic family history as control group. All subjects received 75 gram oral glucose tolerance test(OGTT) and insulin release test and recorded their name, sex, age, hypertension, height, body mass, waist and hip. FFA, glycosylated hemoglobin(HbAlc), MDA, fasting plasma glucose(FPG), postprandial two hour plasma glucose(PPG), triglyceride(TG), total cholesterol(TCH), high density lipoprotein cholesterol(HDL-C), low-density lipoprotein cholesterol (LDL-C) ,apolipoprotein A₁(ApoA₁) and apolipoprotein B₁₀₀(ApoB₁₀₀) weremeasured in all of the subjects. Body mass index(BMI), waist to hip ratio(WHR), Homeostasis model assessment-insulin resistance (Homa-IR), Homeostasis model assessment-beta-cell function(Homa-IS) and insulin sensitivity index(ISI) were calculated.Results:(l)When the influence of age, sex and BMI were eliminated, FPG, PPG, HbAlc, FFA, MDA, TG , LDL-C and Homa-IR were significantly higher and PINS, Homa-IS and ISI were significantly lower in the diabetic patients than those in the controls(P<0.001). TCH, ApoB100> SBP and WHR were higher and FINS and HDL-C were lower in the diabetes group than those in the controls(P<0.05).(2)FPG, PPG, HbAlc, FFA, TG and Homa-IR were higher and Homa-IS and ISI were significantly lower in the normoglycemic first-degree relatives than those in the controls(P<0.05). MDA tended to increase (P=0.052). No significant difference in WHR, FINS, PINS, TCH, HDL-C, LDL-C, ApoA, and ApoBioo between these two groups (P>0.05) .(3) Pearson correlate analysis showed that FFA had significantly positive correlation with FPG and TG in observation group(r=0.289, P=0.031; r=0.273, P=0.042). FFA had positive correlation with Homa-IR, TCH , ApoBioo, BMI, WHR and MDA (r =0.091, r =0.120, r =0.060, r =0.163, r =0.056, r =0.118, each was P>0.05) and had negative correlation with Homa-IS and ISI (r = -0.125, r = -0.039, each was P>0.05) in observation group. MDA had positive correlation with TCH , ApoBioo and HbAlc (r =0.049, r =0.119, r =0.092, each was P>0.05) and had negative correlation with Homa-IS and ISI(r =-0.261, r =-0.140, each was P>0.05) in observation group.(4) When FFA acted as dependent variable and others as independent variable, Logistic regression analysis showed that FBG and TG were entered( partial regression coefficients=0.538 , P=0.035 ; partial regression coefficients =0.376, P=0.048) . This implied that FBG and TG were the risk factors of increasing FFA.(5) When the diabetic patients and their offsprings were matched , 1:1 Paired-samples T Test showed that BM1, WHR, HbA,C, FPG, PPG, Homa-IR, FFA and MDA were significantly higher (P<0.05 â–  PO.05. PO.001, P<0.001, PO.001. PO.001, PO.001, P<0.001) and FINS, PINS, Homa-IS and ISI were significantly lower (PO.01. PO.01? PO.001. P<0.001) in the diabetic patients than those in the offsprings. Pearson correlate analysis showed that FINS, PINS and TCH had significantly positive correlation between the diabetic patients and their offspringsCr -0.325, r =0.351, r =0.228, each was P<0.05) . Conclusions:(l)Type 2 diabetes in diabetic pedigrees had apparent increase in the levels of FFA, MDA and TG . They also had significant insulin resistance and the remarkable deficiencies of islet beta cell and the apparent decrease of their antioxidant ability.(2) The first-degree relatives of type 2 diabetes had had dyslipidoses, insulin resistance and the deficiencies of islet beta cell when they had normal blood glucose. This study showed that the people who had diabetic family history had the tendency to suffer diabetes. Insulin resistance and the deficiencies of islet beta cell and dyslipidoses may be cause diabetes together in these high risk persons. The increasing FFA may be caused by dysglycemia and dyslipidoses . FBG and TG were the risk factors of increasing FFA. The increasing FFA and TG were the major performance and might be the risk factors which promote the occurrence of type 2 diabetes mellitus.(3)Although the increasing MDA had no statistics sense in the normoglycemic first-degree relatives of type 2 diabetes mellitus, the result also showed that their antioxidant ability was declining . The decreasing antioxidant ability may be promote the occurrence of type 2 diabetes mellitus in these high risk persons.(4) Beta cell function and TCH were mostly under genetic control.The risk factors that can cause the occurrence of diabetes mellitus maybe found through the study of the changes and the roles of FFA and MDA in type 2 diabetes mellitus and their normoglycemic first-degree relatives. The research of MDA in this groups have not reported. In this study, we first observed the change of MDA and demonstrated that it tended to increase. This provide a new way to take precautions against diabetes mellitus.Therefore, early preventive measures should be taken to treat the Insulin resistance and dyslipidoses and to monitor their antioxidant ability in the diabetic first-degree relatives. This may be one of the significant measures to prevent or to delay the occurrence of type 2 diabetes mellitus.