Cholesterol-lowering effect of Agemaki, a kind of shellfish, in mice

Agemaki (Sinonovacula constricta) is an edible and popular shellfish in the western part of Japan. The present study demonstrated the effects of feeding Agemaki on cholesterol and triglyceride concentrations in mice plasma and liver. Mice were fed a diet containing 0.1% cholesterol and 0.1% Na-cholate for 1 week, and then a cholesterol-free diet or a cholesterol-enriched one for 2 weeks. To both diets, freeze-dried Agemaki was added at a 5% level. There was no statistically significant effect on the body-weight gain, food intake, and liver weight by feeding Agemaki in both dietary regimens. However, Agemaki significantly lowered the concentrations of plasma and liver cholesterol and also of plasma triglyceride in mice feeding on the cholesterol-rich diet. A similar tendency was also observed for the mice feeding on the cholesterol-free diet. The analysis of freeze-dried Agemaki revealed a relatively larger proportion of n-3 polyunsaturated fatty acids and plant sterols, which may possibly decrease plasma lipids. So far as we know, this is the first report showing hypolipidemic effect of Agemaki.