Alleviating effects of walnut green husk extract on disorders of lipid levels and gut bacteria flora in high fat diet-induced obesity rats

[Display omitted] The walnut green husk has antibacterial, anti-oxidant, anti-inflammatory and other biological activities, but its lipid-lowering activity has not been reported. This study investigated the effects of walnut green husk extract (WGH) on lipid levels and gut bacteria flora in obese rats induced by high-fat diet. The results showed that WGH significantly reduced body weight gain, reversed liver TC, TG, LDL-C, HDL-C, MDA, ALT, AST and serum TC, TG, LDL-C, MDA, leptin levels, insulin resistance and glucose tolerance in high fat diet-induced obesity rats. Meanwhile, fat accumulation, hepatic steatosis and adipose tissue hypertrophy of HFD were reduced by WGH. 16S rRNA sequencing demonstrated that WGH dramaticlly reversed the disorders of gut bacteria flora HFD-induced, reduced the relative abundance of Fusobacteria, Firmicutes and enhanced the relative abundance of Bacteroidetes at the phylum level, reduced the relative abundance of and Peptostreptococcaceae at the family level, furthermore, reduced the relative abundance of Romboutsia, Lachnoclostridium and increased the relative abundance of Bacteroides at the genus level. In conclusion, these beneficial effects of WGH on reducing obesity and lipid disorders could be associated with the modulation of the gut bacteria.