Abstract
Male rats and mice were fed diets containing kibinago (white-striped blue sprat: Spratelloides japonicus), under constant dietary levels of protein (20%), fat (5%) and cholesterol (0.5%). Casein was used as a control protein. Kibinago reduced the serum cholesterol concentration in the test animals. The concentration of serum triglyceride in the kibinago group was lower than that in the control group in both species. Feeding of defatted kibinago to mice did not influence serum lipid levels. Cholesterol concentration in the liver was comparable between the control and the kibinago groups in rats and mice, but was lower in the defatted kibinago group than in the control group in mice. Kibinago and defatted kibinago decreased the hepatic triglyceride level in mice. Feeding with kibinago reduced fecal neutral steroid excretion and increased fecal acidic steroid excretion, resulting in the reduction of total steroid excretion. However, the effect of dietary kibinago on fecal steroids disappeared when it was defatted. These results suggest that the hypocholesterolemic effect of kibinago is attributable to its lipid fraction, whereas non-lipid components contribute to the reduction of hepatic lipids.
