Glycaemia and body mass as determinants of plasma lecithin: cholesterol acyltransferase activity in Nigerian patients with non-insulin dependent diabetes mellitus

Abstract

There is an inverse correlation between plasma high density lipoprotein (HDL) concentrations and atherogenic vascular morbidity risk. An important pathway for modulating circulating HDL levels is the reaction catalysed by the plasma enzyme, lecithin:cholesterol acyltransferase (LCAT). Thus, determinants of LCAT activity should influence plasma HDL levels and be accessible targets for intervention. We therefore assessed such determinants in Nigerian patients with non-insulin dependent diabetes mellitus (NIDDM), classified into age-and sex-matched groups of obese (body mass index, BMI, > 25 kg/m 2) and non-obese (BMI < 25 kg/m 2). Our results indicated that 10 obese diabetic patients had significantly reduced plasma LCAT activity and HDL levels and increased plasma triglyceride (TG) levels, in comparison with the observations in 9 non-obese diabetic patients (all P < 0.05). Furthermore, worsening of glycaemic control, when oral hypoglycaemic treatment was discontinued for 1 week in 10 diabetic (5 obese) patients, further reduced fasting levels of HDL and plasma LCAT activity (both P < 0.05). Although plasma HDL concentrations and LCAT activity levels did not correlate significantly, the latter nonetheless had a significant inverse relationship with fasting plasma glucose levels in the obese diabetic subjects ( r−0.51, P < 0.05). These results indicate that glycaemia and body mass are important determinants of plasma LCAT activity. Both variables are subject to pharmacological and dietary intervention with the objective of increasing circulating HDL levels.