Uncovering the protective mechanism of Pien–Tze–Huang in rat with alcoholic liver injury based on cytokines analysis and untargeted metabonomics

Pien-Tze-Huang (PTH) is a well-known traditional Chinese patent medicine with excellent liver-protection effect. However, the mechanism of hepatoprotective action has not yet been entirely elucidated. The aim of this study was to investigate the mechanism of protective effect of PTH on alcohol-induced liver injury in rats using cytokine analysis and untargeted metabolomics approaches. An alcoholic liver disease (ALD) model with SD rats was established, and PTH was administered according to the prescribed dose. The hepatoprotective effect of PTH was evaluated by pathological observation of liver tissue and changes in biochemical index activity and cytokines in serum. Serum samples were analyzed by ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF/MS), and differentially expressed metabolites were screened by multivariate statistical analysis. KEGG combined with metabolic pathway analysis were used to evaluate the underlying metabolic pathways. Results showed liver histopathology injury was attenuated. The levels of IL-6, TNF-α and NF-κB were significantly decreased in rats intervened with PTH groups, suggesting that it may alleviate inflammation via suppressing the inflammatory cytokines signaling pathway. Eighty differentially expressed metabolites were found and identified. Pathway analysis indicated that the hepatoprotective effects of PTH occurred through the regulation of inflammatory cytokines signaling pathway, primary bile acid biosynthesis, vitamin B6 metabolism pathway, cholesterol metabolism, and tyrosine metabolism. PTH showed favorable hepatoprotective effect through multiple pathways. This study has great importance in fully revealing the mechanism of hepatoprotective action and can help improve the clinical application of PTH.