PLASMA-LIPOPROTEIN COMPOSITION AND CHOLESTERYL ESTER TRANSFER FROM HIGH-DENSITY-LIPOPROTEINS TO VERY-LOW-DENSITY AND LOW-DENSITY LIPOPROTEINS IN PATIENTS WITH NON-INSULIN-DEPENDENT DIABETES-MELLITUS

We have examined cholesteryl ester transfer (GET) from HDL to low dens ity and very low density lipoproteins (LDL and VLDL) and lecithin:chol esterol acyl transferase (LCAT) activity in plasma from 28 men with no n-insulin-dependent diabetes mellitus (NIDDM) treated with diet alone or diet and sulphonylurea drugs and in 27 healthy non-diabetic control s. Patients and healthy subjects had similar LCAT activity, but CET wa s significantly higher in NIDDM 26.1 +/- 11.5 mu mol l(-1) h(-1)) than in healthy men (17.8 +/- 6.5 mu mol l(-1) h(-1)) (p = 0.001). Diabeti c men also had higher CET compared to 15 healthy non-diabetic men (18. 7 +/- 5.6 mu mol l(-1) h(-1)) (p = 0.001) with similar serum lipids. C ET activity was similar in patients treated with diet alone (24.8 +/- mu mol l(-1) h(-1)) or with sulphonylureas (27.7 +/- 15.8 mu mol l(-1) h(-1)). The Sf 0-12 fraction was significantly enriched with total ch olesterol (p = 0.0001) and free cholesterol (p = 0.006) in diabetic su bjects whether treated with diet alone or on sulphonylureas compared t o the 15 non-diabetic controls matched for serum triglycerides. The fr ee cholesterol/phospholipid, the free cholesterol/total protein and th e free cholesterol/mass ratios were increased in the Sf 0-12 fraction in diabetic subjects (p < 0.01). These findings indicate that CET is a ccelerated in patients with NIDDM and that this may be due to the alte red composition of acceptor lipoproteins.