Ginsenoside Rg1 Alleviates Sepsis-Induced Acute Lung Injury by Reducing FBXO3 Stability in an m6A-Dependent Manner to Activate PGC-1α/Nrf2 Signaling Pathway

Background: Sepsis-induced acute lung injury (ALI) is one of the serious life-threatening complications of sepsis and is pathologically associated with mitochondrial dysfunction. Ginsenoside Rg1 has good therapeutic effects on ALI. Herein, the pharmacological effects of Rg1 in sepsis-induced ALI were investigated.

Methods: Sepsis-induced ALI models were established by CLP operation and LPS treatment. HE staining was adopted to analyze lung pathological changes. The expression and secretion of cytokines were measured by RT-qPCR and ELISA. Cell viability and Apoptosis were assessed by MTT assay, flow cytometry and TUNEL staining. ROS level and mitochondrial membrane potential (MMP) were analyzed using DHE probe and JC-1 staining, respectively. FBXO3 m⁶A level was assessed using MeRIP assay. The interactions between FBXO3, YTHDF1, and PGC-1α were analyzed by Co-IP or RIP.

Results: Rg1 administration ameliorated LPS-induced epithelial cell inflammation, Apoptosis, and mitochondrial dysfunction in a dose-dependent manner. Mechanically, Rg1 reduced PGC-1α ubiquitination modification level by inhibiting FBXO3 expression m⁶A-YTHDF1 dependently. As expected, Rg1's mitigative effect on LPS-induced inflammation, Apoptosis and mitochondrial dysfunction in lung epithelial cells was abolished by FBXO3 overexpression. Moreover, FBXO3 upregulation eliminated the restoring effect of Rg1 on CLP-induced lung injury in rats.

Conclusion: Rg1 activated PGC-1α/Nrf2 signaling pathway by reducing FBXO3 stability in an m⁶A-YTHDF1-dependent manner to improve mitochondrial function in lung epithelial cells during sepsis-induced ALI progression.

FBXO3; PGC-1α/Nrf2 pathway; ginsenoside Rg1; mitochondrial function; sepsis-induced acute lung injury.