The Effect On Lipid Metabolism And Insulin Resistance Of High-content DHA/EPA Triglyceride

Sea fish oil which is rich in DHA(Docosahexaenoic acid) andEPA(Eicosapentaenoic acid) has the regulation of adjusting blood lipids, improvingblood sugar, enhancing immunity and increasing intelligence. At present, there aretwo kinds of DHA/EPA products in the market,which is glyceride and ethyl ester.Ethyl ester fish oil is rich in DHA and EPA, but is difficult in digestive absorption.Glyceride is the natural form of fish oil, while is less in DHA and EPA. High-contentDHA/EPA triglyceride has become a mainstream product in international market,butour country has backward production technology of such products.Our lab use theenzymatic catalytic conversion technology to preparate high-content DHA/EPAtriglyceride which has55%DHA/EPA and70%triglyceride. Thses paper whichchoose high-content DHA/EPA as the research product and study the effect on theimprovement of the fatty liver lipid metabolism of rats.High-content DHA/EPA triglyceride could improve the disturbance of lipidmetabolism on fatty liver rats which induced by1%orotic acid. The result shows thatthis high-content DHA/EPA triglyceride can significantly decrease serum and hepaticlipids concentrations and increase the lipids of fecal. This high-content DHA/EPAtriglyceride can significantly decrease serum TC; reduce hepatic TC, TGconcentrations and improve the compose of fatty ccid; increase the contents of totallipids and TC of fecal after given this fish oil for20days.This prompts that this fishoil could improve the disturbance of lipid metabolism on fatty liver rats.To clarify the molecule mechanism by which high-content DHA/EPAtriglyceride laters hepatic lipid metobolism, we examined two pathways related infatty acid biosynthesis and β-oxidation. The data shows that mRNA expression ofhepatic lipogenic related genes like SREBP-1c, FAS, ME and G6PDH weresignificantly inhibited, while mRNA expression of β-oxidation related genes likePPAR-α and CPT-1were upregulated by Realtime-PCR detection. This high-content DHA/EPA triglyceride could inhibite the activity of FAS and ME and enhance theactivity of CPT-1and POE. It could improve the disturbance of lipid metabolism onfatty liver rats through the way of enhancing the catabolism and inhibiting thesynthesis of lipids.Then we induced diabetic mouse model by feeding high fat food and explore theimproved effcct on insulin resistance of high-content DHA/EPA triglyceride.High-content DHA/EPA triglyceride significantly decreased in the level of fastingplasma glucose, reduced serum insulinemia, improved oral glucose tolerance.High-content DHA/EPA triglyceride could not only decrease serum and hepatic lipidsconcentrations, but also improve liver fatty acid composition.Then we induceddiabetic mouse model by feeding high fat food and explored the improved effcct oninsulin resistance of high-content DHA/EPA triglyceride. High-content DHA/EPAtriglyceride significantly decreased in the level of fasting plasma glucose, improvedoral glucose tolerance, reduced serum insulinemia, HOMA-IR and increased thequantity of muscle glycogen, hepatic glycogen. High-content DHA/EPA triglyceridecould not only decrease serum and hepatic lipids concentrations, but also improveliver fatty acid composition.We studied the mechanism of improving insulin resistance of high-contentDHA/EPA triglyceride. The result showed that it significantly enhanced mRNAexpressions of InsR, IRS-2, PI3K and PKB, and decreased GSK-3β expression inliver and muscle. And it could promote GLUT4mRNA expression in adiose andmuscle tissue of mouse. The high-content DHA/EPA triglyceride could regulateinsulin resistance by activating the pivotal genes of PI3K/PKB/GSK-3β insulin signaltransduction pathway.All in all, high-content DHA/EPA triglyceride can effectively improve thedisturbance of lipid metabolism on fatty liver rats and regulate inselin resisitance.Andits effect is better than ethyl ester fish oil and low-content DHA/EPA triglyceride fishoil. It breaks technical monopoly and monopoly of products on DHA/EPA products inthe word and improves international competitiveness of functional food of our country.