PM2.5 mediates mouse testis Sertoli TM4 cell damage by reducing cellular NAD.

ABSTRACT

OBJECTIVE: This study aims to explore the mechanism of PM2.5 damage to the reproductive system of male mice. METHODS: Mouse testis Sertoli TM4 cells were divided into four groups a control group (no additional ingredients except for medium), PM2.5 group (medium containing 100 µg/mL PM2.5), PM2.5 + NAM group (medium containing 100 µg/mL PM2.5 and 5 mM NAM), and NAM group (medium containing 5 mM nicotinamide) and cultured in vitro for 24 or 48 h. The apoptosis rate of TM4 cells was measured using flow cytometry, the intracellular levels of NAD+ and NADH were detected using an NAD+/NADH assay kit, and the protein expression levels of SIRT1 and PARP1 were determined by western blotting. RESULTS: Mouse testis Sertoli TM4 cells exposed to PM2.5 demonstrated an increase in the apoptosis rate and PARP1 protein expression, albeit a decrease in NAD+, NADH, and SIRT1 protein levels (p = 0.05). These changes were reversed in the group treated with a combination of PM2.5 and nicotinamide (p = 0.05). CONCLUSION: PM2.5 can cause Sertoli TM4 cell damage in mouse testes by decreasing intracellular NAD+ levels.