Exploring the Protective Effect of Gastrodia elata Extract on D-Galactose-Induced Liver Injury in Mice Based on the PI3K/Akt Signaling Pathway

In this research, we sought to methodically examine the protective effects of <i>Gastrodia elata</i> extract (GEE) on liver damage induced by D-galactose (D-gal) in mice and clarify the underlying mechanisms. The chemical composition of GEE was characterized using Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS), while network pharmacology analysis was employed to predict potential molecular targets and signaling pathways. A mouse model of liver injury was established through daily intraperitoneal injection of D-gal over a 42-day period, during which the hepatoprotective efficacy of GEE was evaluated. Biochemical, histopathological, and molecular analyses were subsequently performed. UPLC-MS/MS identified ingredients such as amino acids, aromatic compounds, fatty acids, and terpenoids in GEE. A network pharmacology analysis enabled the identification of 272 common targets linked to GEE and liver damage, demonstrating notable enrichment within the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway. In vivo experiments demonstrated that GEE effectively alleviated D-gal-induced body weight loss and elevated liver index values, alleviated hepatic histological damage, and reduced serum levels of Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), and Alkaline Phosphatase (ALP). Furthermore, GEE enhanced the activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), decreased malondialdehyde (MDA) levels, and downregulated the mRNA expression of the pro-inflammatory cytokines Interleukin-6 (<i>IL-6</i>), Interleukin-1 beta <i>(IL-1β</i>), and Tumor Necrosis Factor-alpha (<i>TNF-α</i>). Western blot analysis confirmed that GEE activated the PI3K/Akt pathway, as evidenced by increased ratios of phosphorylated Phosphatidylinositol 3-kinase/Phosphatidylinositol 3-kinase (p-PI3K/PI3K) and phosphorylated AKT/Protein Kinase B (p-AKT/AKT); restored the B-cell lymphoma 2-associated X protein/B-cell lymphoma-2 (Bax/Bcl-2) balance; and reduced cyclin-dependent kinase inhibitor 1 (p21) expression. The results suggest that GEE protects against D-gal-induced liver damage by reducing oxidative stress, inhibiting inflammatory responses, and modulating apoptosis through the activation of the PI3K/Akt signaling pathway, providing support for its potential use in hepatoprotection.