Isofraxidin alleviated radiation-induced testicular damage via the Nrf2/HO-1-NLRP3/ASC Axis

Abstract

OBJECTIVE: Radiotherapy is used to treat patients with tumors; however, radiation (IR)-induced testicular injury, which has no effective treatment approved in clinical practice, significantly influences their prognosis and quality of life. The protective effects and underlying mechanisms of action of isofraxidin (IF) against IR-induced testicular injury were investigated. Methods: A mouse testis injury model was established using 5 Gy irradiation. H&E staining, immunofluorescence staining, and enzyme-linked immunosorbent assay were used to measure DNA damage, apoptosis, inflammatory reactions, and oxidative stress in the testes of mice after irradiation. The effectiveness of IF irradiation on testicular injury was evaluated, and the mechanisms of the related oxidative stress and inflammatory response pathways are discussed. Results: IF can improve IR-induced testicular injury by inhibiting the increased levels of DNA damage, apoptosis rate, oxidative stress, and inflammatory factors. The radioprotective effects of IF on testicular injury are mediated by the stimulation of Nrf2/HO-1 or suppression of NLRP3 inflammasome signaling pathways. In addition, crosstalk between the Nrf2/HO-1 and NLRP3 inflammasome signaling pathways was elucidated, in which the inhibition of the NLRP3 inflammasome was mediated by the activation of Nrf2 signaling with IF upon IR exposure. Conclusion: IF can be a potent radioprotective agent to mitigate testicular damage, and may provide a new therapeutic option to alleviate the side effects of radiotherapy in male patients with tumors.