Research Of The Effect Of Dietary High-cholesterol Seafood On Lipid Metabolism In Animals

The seafood is abundant in high-quality proteins and PUFA, easy to be digested and rich in essential amino acid. It is the important source of DHA and EPA. The annual production capacity and output of seafood around the world was increasing, it is getting essential for the daily life. But the high-cholesterol sea foods represented with the squid, are thought to interrupt the lipid metabolism and increase the concentration of serum cholesterol which is the major risk factor of developing cardiovascular and cerebrovascular diseases, In this paper, eight kind of high-cholesterol seafood were selected to investigate the effect on lipid metabolism in normal and hypercholesterolemia model mouse. Besides, the influence of the squid on lipid metabolism was systemically researched in different animal models.Firstly, the effect of dietary Squid, Prawn, Siliqua minima, Scapharca subcrenata, Solen strictu, Oyster, SeaSnail and Neosalanx tangkehkeii taihuensis chen on lipid metabolism in normal and hypercholesterolemia model mouse were compared respectively. Then, the effect of and mechanism of dietary squid on OA-induced fatty liver in rats were studied. Moreover, the various effects of dietary squid fat and defatted squid, cooked and crude squid on lipid metabolism in mice were also compared. On the other hand, the hamster, which was considered as a useful animal model to study human lipoprotein metabolism, was used to evaluate the effect of dietary squid on lipid metabolism. Finally, the influence of short-term squids fed on the blood lipid metabolism in normal human was discussed.Major achievements were shown as follows:(1)Dietary squid significantly reduced the blood lipid levels in both normal and hypercholesterolemia mouse, increased the hepatic lipid concentrations in normal mouse, while showed no distinct effect on the hepatic lipid in the hypercholesterolemia mouse. (2) The squid feeding prominently reduced hepatic FAS activity and lipid concentrations in fatty liver rats, which indicated that the dietary squid inhibited the aggravation of the NAFLD. The impacts of other sea foods on the blood and hepatic lipid metabolism in normal and hypercholesterolemia mouse were similar to that of squid, while the egg feeding noteworthy increased the blood lipid levels. Compared with the egg, dietary high-cholesterol seafood significantly reduced the concentrations of blood lipids both in normal and hypercholesterolemia mouse.In order to investigate the mechanism of dietary squid on lipid metabolism, the diversity influences of the different major ingredients of the squid were further discussed. The results presented that the reduction of the serum TC levels in the normal and hypercholesterolemia mouse fed with squids was due to the squid fat, while the decrease of the serum TG concentration was due to the conjunct function of squid fat and protein. The squid fat attributed to the enhancement of the hepatic lipid levels in normal mouse fed with squids when the fat and protein jointly acted on the effects of the hepatic lipid metabolism in hypercholesterolemia mouse. Moreover, the impacts of cooked and rude squid were consistent on the blood lipid levels but different on the hepatic lipids.Different dietary ingredients show diverse effects on the digestion and absorption of cholesterol. The results demonstrated that the squid feeding promoted the excretions of total lipid and neutral steroids in low cholesterol diet. The blood lipid metabolism in golden hamsters is close to the human being. This result manifested that dietary squid differently affected the lipid metabolism in mouse and golden hamsters. The squid feeding remarkably decreased the blood lipid levels in the hypercholesterolemia model mouse but in the hypercholesterolemia golden hamsters.According to the results of the animal experiments, the effect of dietary squid on the blood lipid in human being was further confirmed. The result presented here indicated that daily dietary amount of squid significantly decreased serum TG concentration but showed no significantly effect on the serum TC, LDL-C and HDL-C. Besides, dietary squid significantly increased serum DHA and EPA concentrations in human beings. In this study, we systemically investigated the effect of dietary high cholesterol seafood, represented with the squids, on the lipid metabolism in different animals and confirmed the results of the animal experiments in the human intervention trial, which supplied scientific proof for daily sea food consumption.