Aflatoxin B1 promotes autophagy associated with oxidative stress-related PI3K/AKT/mTOR signaling pathway in mice testis

Aflatoxin B1 (AFB1) is a hazard environmental pollutants and the most toxic one of all the aflatoxins. AFB1 can cause a serious impairment to testicular development and spermatogenesis, yet the underlying mechanisms remain inconclusive. Oxidative stress acts as a master mechanism of AFB1 toxicity, and can promote autophagy. Abnormal autophagy resulted in testicular damage and spermatogenesis disorders. The objective of this study was to explore the effect of AFB1 on autophagy in mice testis and its potential mechanisms. In this study, male mice were intragastrically administered with 0, 0.375, 0.75 or 1.5 mg/kg body weight AFB1 for 30 days. We found that AFB1 induced testicular damage, reduced serum testosterone level and impaired sperm quality accompanied with the elevation of oxidative stress and germ cell apoptosis. Interestingly, we observed increasing numbers of autophagosomes in AFB1-exposed mice testis. Meanwhile, AFB1 caused testis abnormal autophagy with the characterization of increased expressions of LC3, Beclin-1, Atg5 and p62. Furthermore, AFB1 downregulated the expressions of PI3K, p-AKT and p-mTOR in mice testis. Taken together, our data indicated AFB1 induced testicular damage and promoted autophagy, which were associated with oxidative stress-related PI3K/AKT/mTOR signaling pathway in mice testis.