Follicular fluid exosomes regulate OVGP1 secretion in yak oviduct epithelial cells via autophagy in vitro

After mammalian ovulation, oocytes enter the oviduct, causing oocyte and oviduct changes. Some studies have shown that follicular fluid exosomes (FEVs) play an important role in this regulatory process, but the specific mechanism is remains unclear. Here, we investigate the effect of FEVs on Autophagy and on the synthesis and secretion of oviductal glycoprotein 1 (OVGP1) in yak oviduct epithelial cells (OECs). We added FEVs to yak OECs and collected samples at intervals. The effect of Autophagy on OVGP1 synthesis and secretion was detected by manipulating the level of Autophagy in OECs. The results showed that Autophagy gradually increased as early as 6 h after exosome intake level increased, and the increase was most obvious 24 h after. At that time, the synthesis and secretion of OVGP1 also reached its highest levels. When the Autophagy level of OECs is changed through the PI3K/Akt/mTOR pathway, OVGP1 synthesis and secretion levels also change, along with the OVGP1 levels in oviduct exosomes also change. More importantly, the addition of FEVs treatment while using 3-MA to inhibit the Autophagy level in yak OECs did not change the synthesis and secretion level of OVGP1. Our results indicate that FEVs can affect the synthesis and secretion of OVGP1 by regulating the level of Autophagy in OECs, and that the completion of this process may depend on the PI3K/Akt/mTOR pathway, indicating that exosomes and Autophagy play important roles in the reproductive physiology of yak OECs. Our results provide new ideas in to characterizing the role of exosomes in yak reproduction.

OVGP1; autophagy; exosomes; follicular fluid exosomes; oviduct epithelial cells.