Nickel induces blood-testis barrier damage through ROS-mediated p38 MAPK pathways in mice

Protective effect of selenomethionine on rabbit testicular injury induced by Aflatoxin B1

The aim of this study was to investigate the alleviating effect of selenomethionine (SeMet) on aflatoxin B1 (AFB1)-induced testicular injury in rabbits. Twenty-five 90-d-old rabbits were randomly divided into 5 groups (the control group, the AFB1 group, the 0.2 mg/kg SeMet + AFB1 group, the 0.4 mg/kg SeMet + AFB1 group and the 0.6 mg/kg SeMet + AFB1 group). After 1 d of the experiment, the SeMet-treated groups were fed 0.2 mg/kg SeMet, 0.4 mg/kg SeMet, or 0.6 mg/kg SeMet daily, and the remaining two groups were fed a normal diet for 30 d. On Day 31, all rabbits in the model group and the three treatment groups were fed 0.5 mg/kg AFB1 for 21 d. The levels of testosterone (T), luteinizing hormone (LH) and follicle stimulating hormone (FSH) in rabbit plasma were detected. Rabbit semen was collected, and its quality was evaluated. Pathological changes in rabbit testes were observed by hematoxylin-eosin (HE) staining. The expression of related proteins in testicular tissue was detected by immunohistochemistry, immunofluorescence and western blot (WB) analysis. Enzyme-linked immunosorbent assays (ELISAs) were used to detect oxidative stress-related indices and inflammatory factors in testicular tissue. The results showed that AFB1 can induce oxidative stress and inflammation to activate the p38/MSK/NF-κB signalling pathway, mediate apoptosis, inhibit the proliferation and differentiation of testicular cells, destroy the integrity of the blood-testis barrier (BTB) and the normal structure of the testis, and reduce the content of sex hormones and semen quality. SeMet pretreatment significantly alleviated testicular injury oxidative stress, and the inflammatory response in rabbits. Thus, we demonstrated that SeMet restores AFB1-induced testicular toxicity by inhibiting the p38/MSK/NF-κB signalling pathway. In addition, in this study, 0.4 mg/kg SeMet had the most impactful effect.

Zearalenone Induces Blood-Testis Barrier Damage through Endoplasmic Reticulum Stress-Mediated Paraptosis of Sertoli Cells in Goats

Zearalenone (ZEA) is present worldwide as a serious contaminant of food and feed and causes male reproductive toxicity. The implication of paraptosis, which is a nonclassical paradigm of cell death, is unclear in ZEA-induced male reproductive disorders. In this study, the toxic effects of ZEA on the blood-testis barrier (BTB) and the related mechanisms of paraptosis were detected in goats. ZEA exposure, in vivo, caused a significant decrease in spermatozoon quality, the destruction of seminiferous tubules, and damage to the BTB integrity. Furthermore, ZEA exposure to Sertoli cells (SCs) in vitro showed similar dysfunction in structure and barrier function. Importantly, the formation of massive cytoplasmic vacuoles in ZEA-treated SCs corresponded to the highly swollen and dilative endoplasmic reticulum (ER), and paraptosis inhibition significantly alleviated ZEA-induced SC death and vacuolization, which indicated the important contribution of paraptosis in ZEA-induced BTB damage. Meanwhile, the expression of ER stress marker proteins was increased after ZEA treatment but decreased under the inhibition of paraptosis. The vacuole formation and SC death, induced by ZEA, were remarkably blocked by ER stress inhibition. In conclusion, these results facilitate the exploration of the mechanisms of the SC paraptosis involved in ZEA-induced BTB damage in goats.