Elucidation of the potential active ingredients and mechanism of Brassica rapa L. extract in alleviating ethanol-induced HepG2 cell injury based on network pharmacology

Prolonged and excessive ethanol consumption is a predominant etiological factor in the pathogenesis of alcoholic liver disease. Brassica rapa L. is an edible medicinal food plant extensively cultivated in Xinjiang, China. Previous studies have implicated it's hepatoprotection function. Here, we sought to delineate the effect and mechanism of Brassica rapa L. extracts on alcohol-induced hepatocyte injury. HepG2 cells were exposed to ethanol to recapitulate alcohol-induced liver injury, whereas Brassica rapa L. extracts significantly attenuated ethanol-mediated hepatocytotoxicity, which was evidenced by decreased cellular levels of aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), and triglyceride (TG). Comprehensive chemical profiling of Brassica rapa L. extracts via high performance liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (HPLC-Q-TOF/MS) elucidated a spectrum of 32 chemical constituents. Network pharmacology analysis identified apigenin, ginger ketone phenol, quercetin, gingerenol, indole-3-acetic acid and azelaic acid as potential bioactive ingredients responsible for hepatoprotection function. Mechanically, bioinformatics analysis suggested the PI3K/AKT axis as the pivotal cascade in mediating hepatoprotective effects of Brassica rapa L. extracts against alcoholic liver injury. Molecular docking simulations further revealed that quercetin and apigenin exhibited stable binding affinities to AKT1 and PI3KCA. Subsequent in vitro assays confirmed that Brassica rapa L. extracts, as well as quercetin and apigenin, mitigated ethanol-induced HepG2 cell injury predominantly through PI3K/AKT pathway activation, which was abolished by the PI3K inhibitor LY294002. These findings lay the groundwork for the potential development of Brassica rapa L. as a functional dietary ingredient to combat alcoholic liver injury.