Tartary Buckwheat Flavonoids Relieve Non-alcoholic Fatty Liver Disease by Inhibiting Lipid Accumulation, Inflammation, and Regulating Intestinal Flora

Non-alcoholic fatty liver disease is characterized by liver damage and steatosis, which is often accompanied by inflammation. Tartary buckwheat flavone has been shown to have a range of anti-inflammatory effects, but its mechanism of action on non-alcoholic fatty liver disease remains unclear. In this study, a non-alcoholic fatty liver disease model induced by high-fat diet in vivo and HepG2 cells stimulated by palmitic acid in vitro were constructed, and the effect of tartary buckwheat flavone on high-fat diet-induced non-alcoholic fatty liver disease and its potential mechanism was explored by H&E staining, PCR, Western blot, and 16S rRNA high-throughput sequencing. The results showed that compared with the high-fat diet group, tartary buckwheat flavone significantly reduced liver and body weight and alleviated pathological damage of liver tissue in mice, and the biochemical indexes of total cholesterol, triacylglyceride, alanine aminotransferase, and aspartate aminotransferase were significantly decreased. Further studies showed that tartary buckwheat flavone significantly reduced the protein levels of inflammatory mediators myeloperoxidase, iNOS, COX2, IL-6, IL-1 beta, and TNF-alpha. In vitro studies also showed that tartary buckwheat flavone significantly improved palmitic acid-induced HepG2 cell lipid accumulation and increased inflammatory factors. Mechanism studies showed that tartary buckwheat flavone alleviated the disorder of lipid metabolism by activating AMPK, decreasing sterol regulatory element-binding protein-1 (SREBP1) and acetyl-COA carboxylase protein levels. Tartary buckwheat flavone significantly inhibited high-fat diet-induced MAPK and NF-kappa B signaling pathways to reduce the release of pro-inflammatory mediators, and then alleviate the inflammatory response. In addition, tartary buckwheat flavone significantly alleviated the intestinal flora disorder induced by high-fat diet through increasing the relative abundance of beneficial bacteria Dubosiella and Bacteroidetes. Our study found that tartary buckwheat flavone alleviates non-alcoholic fatty liver disease by mitigating the disorder of lipid metabolism and inflammatory response and regulating the composition of intestinal flora.