Ginkgo biloba leaf extract alleviates paraquat-induced RLE-6TN cell damage via the miR-155-5p/SIRT1/TLR4 axis.

Ginkgo biloba extract (GBE) has demonstrated therapeutic potential in paraquat (PQ)-induced injury; however, its molecular mechanism remains unclear. The cell viability, lactate dehydrogenase (LDH) release, and apoptosis of RLE-6TN cells were assessed using CCK-8, LDH assay, and flow cytometry. Oxidative stress was evaluated using the DCFH-DA probe, while inflammatory cytokine levels (TNF-α, IL-1β, and IL-6) were measured via ELISA. The expression of miR-155-5p was analyzed using qRT-PCR. Bioinformatics analysis, dual-luciferase reporter assay, and RNA immunoprecipitation (RIP) assay were employed to investigate the interaction between SIRT1 and miR-155-5p. Protein expression levels of SIRT1, TLR4, phosphorylated P65 (p-P65), and total P65 were determined by western blotting. The results showed that miR-155-5p expression was upregulated in PQ-induced cell injury. Knockdown of miR-155-5p improved cell viability and reduced apoptosis, oxidative stress, and inflammatory damage in PQ-treated cells. In RLE-6TN cells, miR-155-5p directly targeted the SIRT1/TLR4 axis. GBE mitigated PQ-induced cell injury by modulating the miR-155-5p/SIRT1/TLR4 axis, thereby enhancing cell viability and reducing apoptosis, oxidative stress, and inflammation. This study indicates that GEB may protect against PQ-induced RLE-cell injury by regulating the miR-155-5p/SIRT1/TLR4 signaling pathway and that miR-155-5p could be a promising biomarker for PQ intoxication, providing novel insights into potential therapeutic strategies for PQ poisoning.