Plasma markers of cholesterol homeostasis in metabolic syndrome subjects with or without type-2 diabetes.

ABSTRACT

AIMS: We investigated the associations between indices of cholesterol metabolism and features of the metabolic syndrome (MS) in the presence and absence of type-2 diabetes (T2DM). METHODS: Men with the MS (N=140) and 10 age- and sex-matched controls were recruited. Plasma lathosterol and campesterol were measured by gas chromatography-mass spectrometry, and their ratios to total cholesterol were used to estimate cholesterol metabolism. RESULTS: Compared with healthy controls, MS subjects had significantly higher lathosterolcholesterol and lower campesterolcholesterol ratios (p<0.05). In the MS subjects without T2DM (N=82), campesterolcholesterol ratio was positively associated with age and negatively associated with plasma triglyceride and insulin concentrations, while in MS subjects with T2DM (N=58), the ratio was positively associated with age and adiponectin concentration, and negatively associated with BMI and insulin. Age and fasting insulin were independent predictors of campesterolcholesterol ratio in MS subjects with T2DM. There was a significant negative association between plasma lathosterolcholesterol with campesterolcholesterol ratio (r=-0.436, p=0.014) in MS subjects without T2DM but not in MS subjects with T2DM. CONCLUSIONS: Cholesterol absorption efficiency was lower and cholesterol synthesis higher in MS subjects with or without T2DM compared with healthy individuals. Moreover, the reciprocal relationship between cholesterol synthesis and cholesterol absorption is lost in the presence of diabetes.