HDL biology
Elevated LCAT and CETP activities help explain abnormal HDL composition in nephrotic-range proteinuria (Kidney Int 1993)
Original title: Role of elevated lecithin: cholesterol acyltransferase and cholesteryl ester transfer protein activities in abnormal lipoproteins from proteinuric patients
LCAT and CETP activities were measured in nine patients with nephrotic-range proteinuria and 18 matched controls, along with the effect of four weeks of ACE inhibition with enalapril on proteinuria and these lipoprotein processes. Proteinuric patients had significantly elevated VLDL and LDL cholesterol, triacylglycerol, and apoB, and lower HDL total cholesterol, free cholesterol, cholesteryl ester, and free cholesterol to cholesteryl ester ratio, with normal total apoA1. Plasma LCAT and CETP activities were elevated by 30% and 39% respectively (both P < 0.01), both inversely related to serum albumin, with VLDL and LDL cholesterol positively related to LCAT and CETP activities and HDL free cholesterol inversely related to LCAT activity. ACE inhibition reduced proteinuria by 40%, partially normalized LCAT activity, and decreased VLDL and LDL cholesterol. The authors conclude that elevated LCAT and CETP activities contribute to the low HDL cholesterol proportion and compositional abnormalities seen in glomerular proteinuria.
Original abstract
Lecithin:cholesterol acyltransferase (LCAT) and cholesteryl ester transfer protein (CETP) are key factors in the esterification of free cholesterol, and the distribution of cholesteryl ester among lipoproteins in plasma. Alterations in these processes may play a role in the lipoprotein abnormalities associated with glomerular proteinuria. The activities of LCAT and CETP were measured using excess exogenous substrate assays in nine patients with nephrotic-range proteinuria and in 18 matched controls. The proteinuria-lowering effect of four weeks of angiotensin converting enzyme (ACE) inhibition with enalapril was also studied. Plasma very low lipoprotein and low density lipoprotein (VLDL and LDL) cholesterol, triacylglycerol and apolipoprotein B levels were significantly elevated in the patients compared with controls. High density lipoprotein (HDL) total cholesterol, free cholesterol, cholesteryl ester and the free cholesterol/cholesteryl ester ratio in HDL were lower. Total plasma apolipoprotein A1 was normal. Plasma LCAT and CETP activities were elevated in the patients by 30% (P < 0.01) and by 39% (P < 0.01), respectively, and were both inversely related to serum albumin. VLDL and LDL cholesterol levels were positively related to LCAT and CETP activities, whereas the HDL free cholesterol content was inversely related to LCAT activity. ACE inhibition resulted in a 40% reduction of proteinuria, a partial normalization of LCAT activity, and a decrease in VLDL and LDL cholesterol. In conclusion, elevated activities of LCAT and CETP may provide a mechanism that contributes to the low proportion of cholesterol in HDL relative to that in VLDL and LDL, as well as to the compositional changes of HDL seen in glomerular proteinuria.(ABSTRACT TRUNCATED AT 250 WORDS)
Summary written by cetpinhibition.org from the published abstract; figures as published. Page updated 19 August 2026. Methods.