Gallic Acid Protects Lung Cells Against Cyclophosphamide-induced Toxicity via Regulating RAGE/NF-κB/autophagy Signaling

Abstract

Objectives: This study aimed to investigate the protective effect of gallic acid (GA) against cyclophosphamide (CYP)-induced lung toxicity with exploring the mechanism of CYP cytotoxicity using normal human lung cells, WI-38 cell line. Methods: WI-38 cells have been categorized into three groups; first group was considered as control, untreated, cells; CYP-group, cells were treated with IC50 concentration of CYP for 24 h; GA+CYP group, cells were pretreated with a selected dose of GA for 24 h then followed by CYP for additional 24 h. After incubation times, cells were collected to evaluate cell viability by trypan blue assay, cell morphology and nuclear condensation by DAPI stain and apoptosis was assessed by AO/EB staining. Lipid peroxidation and total antioxidant capacity were determined in cell lysate biochemically. ELISA technique was applied to determine inflammatory markers (TNF-α and IL-1β), total caspase-3 and LC3-B. RAGE, NF-κB, and Beclin-1 mRNA-expressions were estimated by qRT-PCR. Results: WI-38 cells treated with CYP showed increased cell death by both necrosis and apoptosis with elevated caspase-3 level. Additionally, RAGE expression was up regulated accompanied with activated inflammatory cascade and autophagy. While, GA pretreatment suppressed oxidative stress, inflammatory and autophagy signaling induced by CYP. Conclusion: GA is considered as a promising natural therapeutic option that can halt oxidative damage and RAGE expression activation induced by CYP in lung cells thus preventing lung injury.