Study On The Relationship Between FFA, TNF-α And Type 2 Diabetes Mellitus As Well As Its Macrovascular Complications

ObjectiveType 2 diabetes mellitus is a common and frequently encountered disease in aged people. The incidence and mortality of type 2 diabetes mellitus are increasing in recent years. There are a variety of complications of type 2 diabetes mellitus. The macrovascular complications (MVC) is one of the main causes resulting in diabetic patients' disability and death. Macrovascular complications mainly affects aorta, coronary artery, brain artery, renal arteries, extremity artery, which produces coronary artery disease, ischemic or hemorragic cerebrovascular disease, renal arteries and extremity artery's artherosclerosis. The mechanism of macrovascular complications is extremely complex. It is reported that many factors contribute to macrovascular complications. The level of serum free fatty acids (FFA) and tumor necrosis factor-α(TNF-α) was measured in type 2 diabetic patients with or without macrovascular complications in order to investigate their relationship with type 2 diabetes mellitus and its macrovascular complications.Methods60 diabetic patients who were definitely diagnosed in accordance with the 1999 WHO diagnostic standards were recruited into the study. Among them, 31 cases are with macrovascular complications, while 29 cases without macrovascular complications. In addition, normal controls (NC) of 28 cases were established to facilitate comparison. The level of FFA and TNF-αwas measured by using respectively colorimetric method and enzyme linked immunosorbent assay (ELISA). The fasting plasma glucose (FPG), fasting insulin (FINS), glycosylated hemoglobin (HbA1c), blood-lipid and other indexes were measured and body mass index (BMI) as well as homeostasis model assessment-insulin resistance index (HOMA-IR) calculated.Results1. The level of serum FFA, TNF-αof type 2 diabetic patients with or without macrovascular complications was significantly increased compared with normal controls (P＜0.01). The level of serum FFA and TNF-αin type 2 diabetic patients with macrovascular complications was significantly increased than that in patients without macrovascular complications (P<0.01).2. By bivariate correlation analysis between FFA and age, BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP), FPG, HbA1c, total cholesterol (TC), triglyceride (TG), HOMA-IR, and other indexes in type 2 diabetic patients, level of serum FFA has positive correlation with FPG, TC (respectively r=0.286, 0.295; P<0.05, P<0.05), BMI, HbA1c, HOMA-IR, TG, low density lipoprotein (LDL-C), TNF-α(respectively r=0.545, 0.357, 0.557, 0.380, 0.353, 0.420; P<0.01, P<0.01, P<0.01, P<0.01, P<0.01, P<0.01), and has significantly negative correlation with high density lipoprotein (HDL-C) (r=-0.352, P<0.01).3. By bivariate correlation analysis between TNF-αand age, course of disease, BMI, SBP, DBP, FPG, HbA1c, TC, TG, HOMA-IR, and other indexes in type 2 diabetic patients, the serum of TNF-αhas positive correlation with FPG, HbA1c, TG (respectively r=-0.294, 0.301, 0.256; P<0.05, P<0.05, P<0.05), BMI, HOMA-IR (respectively r=0.494, 0.524; P<0.01, P<0.01).4. By Logistic regression analysis, with type 2 diabetic patients as a whole, with or without macrovascular complications as a dependent variable (with equals to one, and without equals to zero), and with sex, age, course of disease, SBP, DBP, FPG, HbA1c, HOMA-IR, TC, TG, LDL-C, HDL-C, TNF-α, FFA as independent variables, age, course of disease, SBP, TNF-α, FFA finally entered the equations.Conclusion1. The level of serum FFA, TNF-αof type 2 diabetic patients with or without macrovascular complications was significantly increased compared with normal controls. The level of serum FFA, TNF-αof type 2 diabetic patients with macrovascular complications was significantly increased compared with patients without macrovascular complications. By Logistic regression analysis suggests that serum FFA and TNF-αare the risk factors of type 2 diabetic patients with macrovascular complications. 2. Serum FFA, TNF-αhave positive correlation with HOMA-IR, which indicates that FFA, TNF-αmay through insulin resistance accelerate the development of type 2 diabetes mellitus and its macrovascular complications.