Anthropogenic noise exacerbates artificial light at night-induced reproductive behavior deficits in male rats: ameliorative effect of melatonin

The present study investigated the effects of anthropogenic noise or/and artificial light at night on reproductive functions in male rats. Thirty adult male Wistar rats were randomly distributed into five groups (n = 6): Normal control (NC) (0.01% ethanol; p.o.); Light exposed (L) (exposed to 150 lux for 14 h and 5 lux for 10 h daily); Noise exposed (N) (exposed to 100 dB for 6 h daily); Light + Noise exposed (LN) (co-exposure of light and noise); and Light + Noise + Melatonin (10 mg/kg; p.o. for 28 days) (LNM), exposed/treated with stressor/treatment for 28 days. Light and noise stress caused marked reproductive behavior deficits as evident by sexual behavior deficits along with marked oxidative stress in testes. However, TNF-α level was found significantly increased only in testes of noise and LN groups. On the other hand, melatonin treatment significantly mitigated the testicular anomalies, which in turn ameliorated reproductive behavior. Further, molecular docking study strengthened protective role of melatonin in testicular toxicity via showing good binding affinity with TNF-α, iNOS and SOD. In conclusion, the current investigation provides the first comprehensive evidence illustrating the detrimental effects of noise/light stress on reproductive health, and provides insights about the reproprotective effects of melatonin.