Background and aim: Type 2 diabetes mellitus is associated with atherosclerosis, which has been, in part, ascribed to abnormalities in the reverse cholesterol transport system. Among the key actors involved in this pathway is cholesteryl ester transfer protein (CETP) which mediates the transfer of cholesteryl esters (CE) from HDL to apoB-containing lipoproteins.
Methods and results: The purpose of this study was to examine CETP activity in 220 patients with type 2 diabetes mellitus (type 2 DM) treated with diet alone or diet and sulphonylurea drugs and to identify the factors that may regulate it in the diabetic state. We also examined the effect of diet on the activity of plasma CETP in a subgroup of type 2 DM women. CETP activity was assessed by measuring plasma-mediated cholesteryl ester transfer (CET) between pooled exogenous HDL and apoB-containing lipoproteins. In 220 patients with type 2 DM, CET was significantly higher in conjunction with higher plasma triglycerides and lower HDL-cholesterol compared to 100 matched healthy controls. Correlation analysis showed that CETP activity was significantly correlated with the HDL-C to apoA1 ratio (r = -0.205, P = 0.003) and to LDL-C to HDL-C ratio in diabetic women (P = 0.010). Furthermore, CETP activity was correlated marginally with total energy intake (P = 0.052) but to a statistically significant extent with the amount of fat consumed daily (P = 0.008). A significant negative correlation was found between plasma CETP activity and MUFA of plasma phospholipids or free PUFA (P = 0.032), especially with omega3-fatty acids (P = 0.001).
Conclusion: Our findings indicate that CET is accelerated in patients with type 2 DM and that this may be regulated by dietary fatty acids in the diabetic state.