Nano-Selenium Alleviates Heat Stress-Induced Testicular Injury in Roosters via Inhibiting Ferroptosis

The present study investigated the protective effects and molecular mechanisms of nanoselenium (Nano-Se) against heat stress-induced reproductive damage in Hainan Wenchang roosters. Compared with sodium selenite, Nano-Se more effectively improved sperm quality, enhanced activities of testicular antioxidant enzymes (glutathione peroxidase and thioredoxin reductase), and attenuated lipid peroxidation, as indicated by decreased malondialdehyde and protein carbonyl levels under heat stress conditions. Nano-Se also inhibited testicular cell apoptosis and preserved blood-testis barrier integrity. Notably, Nano-Se reduced testicular iron accumulation and suppressed ferroptosis, as evidenced by increased expression of SLC7A11, GPX4, and NQO1 and decreased expression of DMT1 and ACSL4. Consistently, in heat-stressed GC-2 spd(ts) cells, Nano-Se attenuated ferroptosis by reducing iron accumulation, lipid peroxidation, and mitochondrial damage. Mechanistically, the protective effects of Nano-Se were associated with modulation of the SLC7A11/GSH/GPX4 axis and enhanced GPX4 expression. These findings indicate that Nano-Se is an effective antiferroptotic selenium source for mitigating heat stress-induced male reproductive damage.