ELEVATED PLASMA CHOLESTERYL ESTER TRANSFER IN NIDDM - RELATIONSHIPS WITH APOLIPOPROTEIN B-CONTAINING LIPOPROTEINS AND PHOSPHOLIPID TRANSFERPROTEIN

Lecithin:cholesteryl acyl transferase (LCAT) and cholesteryl ester tra nsfer protein (CETP) are key factors in the esterification of choleste rol and the subsequent transfer of cholesteryl ester from high density lipoproteins (HDL) towards very low and low density lipoproteins (VLD L + LDL). Phospholipid transfer protein (PLTP), lipoprotein lipase (LP L) and hepatic lipase (HL) are involved in plasma phospholipid and tri glyceride metabolism and also affect HDL. Equivocal changes in plasma cholesteryl ester transfer have been reported in non-insulin-dependent diabetes mellitus (NIDDM). In 16 NIDDM men with plasma triglycerides less than or equal to 4.5 mmol/l and cholesterol less than or equal to 8.0 mmol/l, plasma cholesteryl ester transfer (CET), cholesterol este rification rate, LCAT and PLTP activity levels were higher (P < 0.05 t o P < 0.02) in conjunction with higher plasma triglycerides (P < 0.01) and lower HDL cholesterol and cholesteryl ester levels (P < 0.05) com pared to 16 matched healthy men. Multiple stepwise regression analysis demonstrated that CET was positively related to VLDL + LDL cholestero l (P < 0.001), triglycerides (P = 0.001), PLTP activity (P=0.007) and CETP activity (P=0.008, multiple r-0.94). NIDDM had no effect on GET, independently from these parameters. HDL cholesteryl eater was negativ ely related to CET (P = 0.017), HL activity (P = 0.033) and NIDDM (P = 0.047) and positively to LCAT activity levels (P = 0.034, multiple r = 0.68). It is concluded that the elevated CET in plasma from NIDDM pa tients is associated with higher plasma triglycerides and PLTP activit y levels. Furthermore, our data suggest that in normo- and moderately dyslipidaemic subjects PLTP and CETP activity levels per se may influe nce the rate of cholesteryl ester transfer in plasma. Plasma cholester yl ester transfer appears to be a determinant of HDL cholesteryl ester , but other factors are likely to contribute to lower HDL cholesteryl ester levels in NIDDM. (C) 1998 Elsevier Science Ireland Ltd. All righ ts reserved.