Endocrine Abstracts

Introduction: Mechanisms by which visceral obesity and insulin resistance (IR) contribute to atherogenesis are complex and not entirely known. One of the atherogenic factors involved in foam cells formation is scavenger receptor CD36 expressed on monocytes, endothelial cells, adipocytes and platelets, participating in oxidized LDLs absorption and foam cells formation – processes that initiate atheroslerosis. Many factors can influence the expression of receptor CD36.

Aim: To assess the impact of type of obesity and IR on CD36 expression on peripheral blood monocytes.

Materials and methods: The study population consisted of 75 women aged 25–45 years was divided into 3 groups: A1 – 30 obese women with IR, A2 – 30 obese women without IR and control group C – 15 nonobese women. Physical examination included body mass, body mass index (BMI), waist and hip circumferences and waist to hip ratio (WHR) evaluation. CD36 expression was evaluated using flow cytometry. Oral glucose tolerance test (OGTT) with concomitant insulin evaluation was performed. Glucose concentration was measured using enzymatic method and insulin with chemifluorescence method. IR (HOMA, FIRI) and insulin sensitivity (QUICKI) indices were estimated.

Results: BMI, WHR, total insulin and total glucose levels during OGTT, HOMA and FIRI were significantly higher in A1 group than in groups A2 and C. In contrast, QUICKI was significantly lower in group A1 than in A2 and C. Expression of CD36 on monocytes did not differ among A1 and A2 groups and was significantly lower in those both than in controls. There were no significant correlations between CD36 expression and BMI, WHR and IR indices.

Conclusions: Expression of scavenger receptor CD36 on monocytes in obese women is significantly lower than in lean individuals. IR indices in obese women show no significant influence on CD36 expression. Obesity significantly reduces CD36 expression and coexisting IR has no infuence on CD36 expression.