Enhanced autophagy reversed aflatoxin B1-induced decrease in lactate secretion of dairy goat Sertoli cells.

The deleterious effects of aflatoxins, especially aflatoxin B1 (AFB1) which are widespread at all stages of food production, on the reproductive system have been widely reported in males. However, it is still far from fully understood about the toxic effect and molecular mechanism after exposure to AFB1 in various testicular cells, especially Sertoli cells (SCs) which provide various energy materials and support to the developing germ cells as nurse cells. In this work, we examined the effects of AFB1 in dairy goat SCs on lactate production and autophagy, and the role of autophagy on AFB1-induced reduction in lactate production. Mechanistically, AFB1 destroyed the energy balance and reduced the secretion of lactate in dairy goat SCs (P < 0.01), resulting in a reduced level of ATP (P < 0.01) and phosphorylation of AMPK (P < 0.01). Subsequently, activated AMPK triggers autophagy by directly phosphorylating ULK1 (P < 0.05). The enhancement of autophagy partially reversed the AFB1-induced decrease in lactate secretion by promoting glucose utilization (P < 0.01) and increasing the expression of proteins related to lactate secretion in dairy goat SCs (P < 0.05) such as GLUT1, GLUT3, LDHA, and MCT4. Collectively, our study suggests that AFB1 inhibits the secretion of lactate which supply for germ cell development by damaging the "Warburg-like" metabolism of dairy goat SCs. Moreover, autophagy contributes to the resistance of glucose metabolism damage induced by AFB1. DATA AVAILABILITY: All data generated or analyzed in this study are available from the corresponding authors upon request.

TLR7/8 agonist (R848) inhibit bovine X sperm motility via PI3K/GSK3α/ß and PI3K/NFκB pathways.

Sex-control technology have great economic value and is one of the hot topics in livestock research. To produce more milk, dairy farmers prefer female offspring. X/Y sperm separation is an effective method for offspring sex control. Currently, the major commercial production method for sperm separation is flow cytometry sorting in cattle. However, flow cytometry requires expensive equipment and long sorting times. So, a simple and inexpensive method for producing a higher number of dairy cows is required. In this study, R848 activates toll-like receptor 7/8 (TLR7/8), thereby separating X from Y sperm. The results showed TLR7/8 is expressed in the tail of X sperm. Immunofluorescence (IF) of testes, epididymis, and ejaculate shows that the number of TLR7+/8+ sperm cells is up to 50 %. Furthermore, TLR7/8 agonist (R848) affects mitochondrial function through the PI3K/GSK3α/ß/hexokinase and PI3K/NFκB/hexokinase signalling pathways, inhibiting X sperm motility, while the motility of Y-sperm remains unchanged. The difference in sperm motility causes Y sperm (with high motility) to move to the upper layer and X-sperm (with low motility) to the lower layer allowing the separation of X and Y sperm. Based on this study, we reveal a simple and effective method for enriched X/Y sperms from cattle.

Zearalenone induces oxidative stress and autophagy in goat Sertoli cells.

Zearalenone (ZEA), one of the non-steroidal estrogen mycotoxin, can cause male reproductive damage and genotoxicity in mammals. Testicular oxidative injury is an important factor causing male sterility. Testicular Sertoli cells are essential for spermatogenesis and male fertility. At present, the mechanism of oxidative injury in dairy goat Sertoli cells after exposure to ZEA remains unclear. This study explored the effects of ZEA on oxidative stress and autophagy in dairy goat Sertoli cells. It was found that treatment of primary Sertoli cells with 25, 50 and 100 µmol/L ZEA for 24 h can promote ROS production, decrease cell viability, antioxidant enzyme activity and mitochondrial membrane potential, induce caspase-dependent cell apoptosis and autophagy activity. ZEA-induced autophagy was confirmed by LC3-I/LC3-II transformation. More importantly, N-acetylcysteine (NAC) pretreatment can remarkably inhibit ZEA-induced oxidative stress, apoptosis and autophagy in Sertoli cells by eliminating ROS. In conclusion, this study indicates that ZEA induces oxidative stress and autophagy in dairy goat Sertoli cells by promoting ROS production.

FSH-inhibited autophagy protects against oxidative stress in goat Sertoli cells through p62-Nrf2 pathway.

Oxidative stress is a common cause of male infertility. Sertoli cells are one of the target cells of oxidative injury, which leads to impaired testicular function. Follicle-stimulating hormone (FSH) is critical in Sertoli cell function. However, the role of FSH in the response of goat Sertoli cells to H2O2-induced oxidative stress has not been studied yet. To investigate this response, we established an oxidative stress model using goat Sertoli cells. FSH pretreatment significantly enhanced the decreased cell viability (p < 0.05) caused by oxidative injury and inhibited autophagic flux. FSH significantly increased p62 mRNA and protein levels (p < 0.01). Further investigations revealed that FSH also increased the expression level and nuclear translocation of Nrf2 in Sertoli cells (p < 0.01), which resulted in increased antioxidant enzyme activity (p < 0.05). In contrast, treatment with siNrf2 and sip62 abolished this protective effect of FSH. These findings suggest that FSH protects Sertoli cells against oxidative stress via the p62-Nrf2 pathway, and that p62 accumulation maintains persistent activation of Nrf2. Thus, p62 and Nrf2 are required for FSH-mediated protective role in H2O2-induced Sertoli cell injury. The findings reveal new mechanisms by which FSH protects against oxidative injury in goat Sertoli cells.