Jannatifar R, Cheraghi E, Nasr‐Esfahani MH, et al. - In this study, the impacts of N‐acetyl‐cysteine (NAC) supplementation on the expression of heat shock protein A2 (HSPA2) was investigated. Researchers assessed semen samples from 50 astheno‐terato‐zoospermic men who have received NAC (600 mg/day) orally for three months for expression HSPA2 using RT‐PCR and Western blot analysis. They evaluated semen samples of these individuals for sperm parameters, DNA fragmentation, protamine deficiency, lipid peroxidation index, and total antioxidant capacity. It was shown that HSPA2 expression is significantly related to most of the assessed parameters. This study’s findings demonstrate that NAC may directly or indecently impose its beneficial effect through increased expression of heat shock protein A2, which plays a potential role in the proper folding of elements needed to counteract stress conditions in infertile individuals.