Ochratoxin A exposure decreased sperm motility via the AMPK and PTEN signaling pathways

Highlights: • OTA exposure significantly decreases boar spermatozoa motility in vitro. • OTA exposure increases the level of reactive oxygen species. • OTA exposure activates the PTEN/AMPK signaling pathways. Ochratoxin A (OTA), a common mycotoxin found in nature, has been implicated as effecting the function of male reproductive systems. OTA exposure has been shown to decrease sperm production and quality, however, the underlying mechanisms remain unknown. In the current investigation boar sperm exposed to 10 and 100 μM OTA in vitro for 24 h resulted in significantly decreased motility, in the 100 μM OTA treatment group when compared with the control group. The level of reactive oxygen species (ROS) was significantly increased in both of the OTA treatment groups. The increase in ROS activated phosphatase and the tensin homolog deleted on chromosome ten (PTEN) and inhibited the activation of protein kinase B (PKB, AKT), activated adenosine 5′-monophosphate (AMP), and activated protein kinase (AMPK) in the exposed sperm. Furthermore, activation of AMPK was enhanced by a decrease in ATPase. These changes culminated in a decline in boar sperm motility. PTEN/AMPK inhibitors significantly inhibited the expression of the two proteins in the OTA treatment group. In addition, there was increased expression of apoptosis markers in the OTA exposed sperm. In conclusion, these data suggest that OTA exposure affects the sperm motility via the AMPK and PTEN signaling pathways.