Characterization and mechanisms of lipid metabolism in high-fat diet induced hyperlipidemia in Mongolian gerbil ( Meriones unguiculatus )

Abstract

Rodent are common animal models for hyperlipidemia. In the present study, the differences in lipid metabolism between gerbils and rats were investigated. Feeding a high-fat diet led to a significant increase in serum total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDLC) and high-density lipoprotein cholesterol (HDLC) in gerbils, and were found in a time-dependent manner during 0 to 16 weeks’ feeding. Hepatic lipid vacuolization and even fibrosis in gerbils were greatly formed in response to the high fat diet with the characteristic of serum LDLC increase, while those remained lower changed or unchanged in rats. Furthermore, serum lecithin cholesterol acyl transferase (LCAT) activities in the hyperlipidemia gerbils were significantly higher than those in the normal ones, which were also in line with increased LDLC-TG secretion rate and impaired hepatic function in gerbils in response to the high-fat diet. Therefore, gerbils were considered to be more sensitive to high fat diet, less time-consuming in forming hyperlipidemia. Similar response in increased LDLC levels to cholesterol as human and may warrant further application as a possible model for drug evaluation and lipid metabolism. Key words : Mongolian gerbil , hypercholesterolemia, low-density lipoprotein cholesterol, lecithin cholesterol acyl transferase.