Ginsenoside Rh2 Ameliorates Pulmonary Fibrosis Via Hsp70-P53-Dependent Autophagic Flux Regulation and Senescence Arrest

Abstract

AbstractBackground: Pulmonary fibrosis (PF) is an age-related disease characterized by persistent alveolar injury and repeated cycles of destruction, repair, reconstruction, and excessive deposition of extracellular matrix, posing a significant threat to health. Ginsenoside Rh2 (G-Rh2), a natural tetracyclic triterpenoid compound, exhibits good anti-tumor activity; however, its role in anti-fibrotic processes has not been fully investigated. This study explores the effect of G-Rh2 on bleomycin (BLM)-induced PF and its molecular mechanisms.Method: Male C57BL/6 mice were subjected to PF by a single intratracheal instillation of bleomycin (BLM, 5 mg/kg). After 4 days, mice were orally administered G-Rh2 (2.5 or 5 mg/kg/day) or pirfenidone (PFD, 100 mg/kg/day) for 24 consecutive days. In parallel, mouse alveolar epithelial cells (MLE-12) were treated with BLM, and an HSP70 knockdown cell line was constructed. During the experiment, various analyses were performed, including western blotting, immunofluorescence, histological examination, and transmission electron microscopy observation.Results: Through in vivo and in vitro studies, it was found that G-Rh2 can disrupt the HSP70-p53 complex, thereby inhibiting cell senescence, improving mitochondrial autophagy disorders induced by BLM, and suppressing the activation of the TGF-β1/Smad pathway. By knocking down HSP70, it was found that the therapeutic effect of G-Rh2 was significantly weakened. This suggests that G-Rh2 may enhance its anti-fibrotic effects by acting as a natural HSP70 inducer and up-regulating the expression of HSP70.Conclusion: This study reveals that G-Rh2 exerts a significant anti-PF effect by activating HSP70, providing a theoretical basis for its potential as an anti-PF therapeutic agent.

Note:
Funding declaration: This work was supported by the grant of the National Key Research and Development Program (2023YFD1601600).

Conflict of Interests: The authors declare no conflict of interest.

Ethical Approval: All animal experiments were approved by the Institutional Animal Care and Use Committee of Jilin Agricultural University (IACUC No. 2025109001) and performed following institutional guidelines.

Keywords: Ginsenoside Rh2, Pulmonary fibrosis, Heat shock protein 70, Cellular Senescence, Mitochondria