Protective Effects of SNS and Its Medicinal and Food Homology Formulas on CCl₄-injured HepG2 Cells

Research and development of natural drugs with liver protective function based on theory of traditional Chinese medicine has been widely proved to be practicable. However, the development of functional foods with liver protective function based on Chinese herbal prescriptions is limited. In this study, an effective prescription for the treatment of liver disease named Sini San (SNS) was selected. Three alternative formulas including Zhizi alternative formula (ZZT), Sangye alternative formula (SYT) and Jinyinhua alternative formula (RDT) were obtained by replacing Radix Bupleuri to gardenia (ZZT), mulberry leaves (SYT) and honeysuckle (RDT), respectively, based on network pharmacology analysis. The effects of different concentrations (100 and 200 μg/mL) of substitutes on HepG2 cells treated with 0.6% carbon tetrachloride (CCl₄) solution for 24 h were further studied. The results demonstrated that the intervention of these four formulas could markedly (P<0.05) diminish the elevation of cellular alanine aminotransferase (ALT), aspartate aminotransferase (AST), and malondialdehyde (MDA) up to 26.57% (SNS), 68.98% (RDT), and 34.00% (RDT) compared to the model group, respectively. Additionally, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) increased significantly (P<0.05) up to 223.76% (SNS), 120.74% (RDT), and 182.67% (RDT), respectively. As for the genes and protein expression, the intervention of formulas significantly (P<0.05) up-regulated the gene expression levels of Nrf2, HO-1, Keap1 and AKT up to 820.48% (SYT), 246.31% (RDT), 270.15% (SYT), and 222.44% (SYT), respectively. Correspondingly, the expression of Keap1, Nrf2, HO-1, AKT (except ZZT), Bcl-2 proteins was up-regulated (P<0.05) while Caspase-3, Bax proteins down-regulated (P<0.05), it could also significantly (P<0.01) reduce the rate of apoptosis. These results suggest that SNS and alternative formulas may protect against the toxic effects of CCl₄ on cells through controlling oxidative stress and cell apoptosis pathways, and that the theory of nature, taste and meridian attribution and network pharmacology analysis can be used to guide the development of functional foods.