Effect of Walnut Meal Peptides on Hyperlipidemia and Hepatic Lipid Metabolism in Rats Fed a High-Fat Diet.

As a natural active substance that can effectively improve blood lipid balance in the body, hypolipidemic active peptides have attracted the attention of scholars. In this study, the effect of walnut meal peptides (WMP) on lipid metabolism was investigated in rats fed a high-fat diet (HFD). The experimental results show that feeding walnut meal peptides counteracted the high-fat diet-induced increase in body, liver and epididymal fat weight, and reduce the serum concentrations of total cholesterol, triglycerides, and LDL-cholesterol and hepatic cholesterol and triglyceride content. Walnut meal peptides also resulted in increased HDL-cholesterol while reducing the atherosclerosis index (AI). Additionally, the stained pathological sections of the liver showed that the walnut meal peptides reduced hepatic steatosis and damage caused by HFD. Furthermore, walnut meal peptide supplementation was associated with normalization of elevated apolipoprotein (Apo)-B and reduced Apo-A1 induced by the high-fat diet and with favorable changes in the expression of genes related to lipid metabolism (LCAT, CYP7A1, HMGR, FAS). The results indicate that walnut meal peptides can effectively prevent the harmful effects of a high-fat diet on body weight, lipid metabolism and liver fat content in rats, and provide, and provide a reference for the further development of walnut meal functional foods.

Walnut green husk polysaccharides prevent obesity, chronic inflammatory responses, nonalcoholic fatty liver disease and colonic tissue damage in high-fat diet fed rats.

High-fat (HF) diets cause obesity, gut microbial dysbiosis and associated disorders and inflammatory bowel disease (IBD) due to increased intestinal permeability, which is an important reason for chronic inflammation and oxidative stress. This study was to investigate the effects and mechanism by which walnut green husk polysaccharides (WGHP) prevents obesity, oxidative stress, inflammation, liver and colon damage in HF diet induced rats. We found that WGHP alleviated HF-induced abnormal weight gain, disordered lipid metabolism, inflammation, oxidative stress, colonic tissue injury and up-regulate the expression level of colonic tight junction protein in the rats. Besides, the administration of WGHP promoted browning of iWAT and thermogenesis in BAT of HF-fed rats, and improved gut microbiota dysbiosis by increasing the bacterial diversity and reducing the relative abundance of potential pathogenic bacteria in the colon of the rats. Furthermore, WGHP consumption not only increased the SCFAs content but also improved the relative abundance of Prevotellaceae and Allobaculum in the gut of rats. Our results suggest that the protective effect of WGHP on metabolic inflammation caused by HF may be due to the regulation of gut microbiota and SCFAs.