Solanum nigrum Protects against Hepatic Fibrosis via Suppression of Hyperglycemia in High-Fat/Ethanol Diet-Induced Rats

Background: Advanced glycation end products (AGEs) signal through the receptor for AGE (RAGE), which can lead to hepatic fibrosis in hyperglycemia and hyperlipidemia. We investigated the inhibitory effect of aqueous extracts from Solanum nigrum (AESN) on AGEs-induced RAGE signaling and activation of hepatic stellate cells (HSCs) and hyperglycemia induced by high-fat diet with ethanol. Methods: An animal model was used to evaluate the anti-hepatic fibrosis activity of AESN in rats fed a high-fat diet (HFD; 30%) with ethanol (10%). Male Wistar rats (4 weeks of age) were randomly divided into four groups (n = 6): (1) control (basal diet); (2) HFD (30%) + ethanol (10%) (HFD/ethanol); (3) HFD/ethanol + AESN (100 mg/kg, oral administration); and (4) HFD/ethanol + pioglitazone (10 mg/kg, oral administration) and treated with HFD for 6 months in the presence or absence of 10% ethanol in dietary water. Results: We found that AESN improved insulin resistance and hyperinsulinemia, and downregulated lipogenesis via regulation of the peroxisome proliferator-activated receptor α (PPARα), PPARγ co-activator (PGC-1α), carbohydrate response element-binding protein (ChREBP), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS) mRNA levels in the liver of HFD/ethanol-treated rats. In turn, AESN may delay and inhibit the progression of hepatic fibrosis, including α-smooth muscle actin (α-SMA) inhibition and MMP-2 production. Conclusions: These results suggest that AESN may be further explored as a novel anti-fibrotic strategy for the prevention of liver disease.