Comparative biochemical studies on plasma cholesterol. II. Relationship between plasma esterified cholesterol and lecithin: Cholesterol acyltransferase activity.

Abstract

In five animals, blue crab, crayfish, carp, rat and man; their plasma lecithin: cholesterol acyltransferase (LCAT) activities were determined from the aspect of comparative biochemistry. The activities of mammalian blood plasma are much higher than those of carp blood and crustacean haemolymph plasma. Moreover, it was found that there is an apparent linear relationship between the LCAT activities and the ratios of cholesterol ester to total cholesterol. But the ratios of trigly cerides to total lipids do not correlate with the LCAT activities, differing from the case of the diabetic mellitus patients. Therefore, it is probable that the plasma esterifying rate of cholesterol is governed by the ratios of cholesterol ester/total cholesterol, and it seems that plasma esterified cholesterol increases with the evolution of animals.

Survival, molting pattern, and growth of early blue swimmer crab, Portunus pelagicus, juveniles fed diets containing varying levels of cholesterol

“…It has been reported that, when clawed lobsters, Homarus sp., were fed a phosphatidylcholine deficient diet, their cholesterol transport was negatively affected (D'Abramo, Bordner, & Conklin, ), and a similar situation was also reported for the Kuruma shrimp, M. japonicus (Teshima & Kanazawa, ). Mankura, Dalimunthe, and Kayama () compared the level of cholesterol esterification in crustaceans, fish, rats, and human beings and suggested that crustaceans had the lowest lecithin: cholesterol acyltransferase activity, which is responsible for cellular cholesterol metabolism, particularly cholesterol contained in plasma lipoproteins. In a previous study with P. pelagicus juveniles of a size similar to those used here, dietary phospholipid (PL) supplementation was reported to markedly improved their growth, and optimal growth was achieved when the crabs were fed diets containing a PL level of >79 g/kg PL (Noordin et al, ).…”