Profile of dyslipidemia in Psammomys obesus, an animal model of the metabolic syndrome.

OBJECTIVE: To investigate lipid profiles in Psammomys obesus and relationships between lipid profile and other components of the Metabolic Syndrome. METHODS: A total number of 49 adults with a wide range of body weight and glucose tolerance were studied in a cross-sectional analysis. Plasma cholesterol distribution profiles were measured by size exclusion lipid chromatography. Blood glucose was measured using an enzymatic glucose analyser, and plasma insulin was determined by radioimmunoassay. RESULTS: Obese diabetic Psammomys obesus had elevated plasma cholesterol (P=0.003) and triglyceride levels (p>0.001) compared to their lean littermates. The hypercholesterolemia was mainly due to increased circulating levels of VLDL-cholesterol (P=0.003) and LDL-cholesterol (P=0.003) in these animals. Multiple linear regression analyses revealed that body weight was independently associated with plasma cholesterol (P=0.011) and LDL concentration (P=0.009), while plasma insulin was associated with VLDL-cholesterol concentration (P=0.005). All of the variables measured exhibited continuous distributions across a wide range of phenotypes, from a normal rodent lipid profile to profound dyslipidemia. CONCLUSIONS: These data suggest that the dyslipidemia in obese, diabetic Psammomys obesus is closely associated with other components of the Metabolic Syndrome, including obesity and insulin resistance.