Huang-Qi San improves glucose and lipid metabolism and exerts protective effects against hepatic steatosis in high fat diet-fed rats

Abstract Numerous researches supported that non-alcoholic fatty liver disease (NAFLD) was an emerging problem associated with increased visceral adiposity (obesity), diabetes and related metabolic disorders. Huang-Qi San (HQS) is composed of three traditional Chinese medicines (Astragali Radix, Pueraria Radix and Cortex Mori Radicis) with a weight ratio of 1:2:1. HQS has been reported to be effective in improving glucose-lipid metabolism, but its underlying mechanism on NAFLD has not been fully understood. The purpose of the present study was to assess the protective effects of HQS on obesity-induced hepatic steatosis in rats fed with high fat diet (HFD). Our data revealed that administration of HQS (1.2 and 2.4 g/kg body weight) resulted in significant reduction in body weight (BW) and organs coefficients of visceral fat. The full-Body CT scan demonstrated that HQS reduced liver fat ratio, visceral and subcutaneous fat mass in a dose-dependent manner. Additionally, HQS decreased plasma TC, TG, FFA and FABP4 levels, normalized glucose and insulin levels, and improved the glucose tolerance. Pathological examination showed that HQS alleviated hepatic steatosis and reduced the cell size of epididymal visceral adipose tissue. Hepatic lipid accumulation was also reduced by HQS treatment compared with HFD fed rats. RNA-Seq analysis combining with qPCR demonstrated that the mRNA expression of some important glucose and lipid metabolism-related genes including Acat2, Apoc4, Bhmt, Cyp3a62, Cyp51, Egln3 (Phd3), Fads1, Fads2, Gnmt, Hmgcs1 and Pemt, were significantly changed by HQS treatment. Taken together, these results suggested that HQS had beneficial effects on glucose-lipid metabolism and hepatic steatosis, and its mechanism might be related to the functions of the genes in regulating glucose and lipid metabolism.