Endocrine Abstracts

Background: Obesity represents a cardiovascular risk factor. Monocyte chemoattractant protein-1 (MCP-1) is a known regulator of monocyte recruitment to sites of inflammation, and participates at the early phases of atherogenesis. Apolipoproteins, as part of the lipoprotein particles, are classically coupled with cardiovascular risk distinction.

Aims: To assess the association of anthropometric parameters, insulin resistance and MCP-1 levels with classic lipid and apolipoprotein profile, in both obese and normal-weight premenopausal women.

Methods: We studied 72 obese (age=34.6±7.8 years, BMI=44.4±8.5 kg/m², waist circumference=118.6±15.1 cm) and 73 normal-weight pre-menopausal women (age=33.6±8.4 years, BMI=21.4±1.7 kg/m², waist circumference=71.5±5.8 cm). Women were characterized for anthropometrics and a fasting blood sample was collected for MCP-1, insulin, glucose, total, LDL and HDL-cholesterol, triglycerides, free fatty acids and apolipoproteins A-I, A-II, B, C-II, C-III and E; insulin resistance was assessed by the homeostatic model assessment (HOMA-IR). We compared biochemical parameters between groups. In each group, we looked for correlations of lipid/apolipoprotein profile with MCP-1, insulin resistance and anthropometrics.

Results: Obese women presented significantly higher triglycerides (P<0.001) and MCP-1 levels (P=0.001) and significantly lower levels of HDL-cholesterol (P<0.001) and apolipoprotein A-I (P<0.001); we also found a trend for lower apolipoprotein A-II (P=0.07). In the obese group (but not in the non-obese), MCP-1 was directly correlated with apolipoprotein E (P=0.007; r=0.35) and inversely associated with HDL-cholesterol (P=0.013; r=−0.321) and apolipoprotein A-I (P=0.021; r=−0.3). HOMA-IR was inversely associated with HDL-cholesterol (P=0.032; r=−0.252) and directly associated with triglycerides (P=0.003; r=0.344). MCP-1 was not correlated with anthropometrics or HOMA-IR.

Conclusions: The higher levels of MCP-1 and triglycerides and lower levels of HDL-cholesterol/apolipoprotein A-I observed in the obese women are consistent with a higher atherosclerotic activity. The association of MCP-1 levels with apolipoproteins A-I and E in obese women, independently from anthropometrics or insulin resistance, may indicate a way of regulation of the atherosclerotic activity in obesity.