Polyphenols-rich extracts from walnut green husk prevent non-alcoholic fatty liver disease, vascular endothelial dysfunction and colon tissue damage in rats induced by high-fat diet

Abstract

This study is aims to evaluate the beneficial effects of polyphenols-rich extracts from walnut green husk (WGHP) on the prevention of obesity, nonalcoholic fatty liver disease (NAFLD), vascular endothelial dysfunction and colon tissue damage in rats fed high fat diet for 8 weeks. HPLC analysis showed that epicatechin, rutin and caffeic acid are the main components of WGHP. Administration of WGHP to HF-fed rats effectively prevented abnormal body weight gain, lipid metabolism disorder, oxidative stress and inflammation. Biochemical analysis and histopathological observation consistently confirmed the protective effects of WGHP on NAFLD, vascular endothelial dysfunction and colon tissue damage in rats caused by HF. In addition, 16S RNA sequencing results showed that WGHP reduced the Firmicutes/Bacteroidetes ratio in HF-fed rats and reversed the relative abundance of Ruminococcaceae-UCG-014 and Fusicatenibacter. These results suggest that WGHP may serve as a nutritional agent for protecting liver, cardiovascular and colon tissue in HF-fed rats.

Keywords

• Walnut green husk
• Polyphenol
• Obesity
• Nonalcoholic fatty liver disease
• Gut microbiota