Hydrogen sulfide repairs testicular damage induced by heat stress in rats.

Heat stress can cause testicular damage and affect male fertility. The gasotransmitter hydrogen sulfide (H₂S) is involved in various physiological and pathophysiological processes, with antioxidant and anti-inflammation effects. The aim of this study was to investigate whether H₂S could reduce the testicular damage caused by heat stress. In this study, we constructed a rat heat-stress model and treated it with H₂S. Histopathology, high-throughput sequencing, bioinformatics analysis and molecular biology methods were used to investigate whether H₂S donor NaHS could alleviate heat stress-induced testicular injury and to explore the underlying mode of action of H₂S. Heat stress reduced testis index, sperm quality, sex hormone levels and disturbed testicular structures. High-throughput transcriptome sequencing and Gene Ontology (GO) enrichment analyses showed that genes involved in inflammation were upregulated in the heat stress group compared to the control group. H₂S treatment increased testis index, sperm quality and attenuated pathological alternation and hormone disorder in rats exposed to heat stress. Furthermore, H₂S administration reversed increased inflammatory factors tumor necrosis factor-α, interleukin-1β and interleukin-6, and resulted in a significant decrease in malondialdehyde levels and in increased activity of catalase and ratio of reduced/oxidized glutathione compared to the heat stress group. This study suggests that H₂S donor NaHS can effectively restore testicular damage caused by heat stress in rats by inhibiting inflammation and oxidative stress.