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.

Exosomes in the follicular fluid can carry and transfer regulatory molecules to recipient cells, thus influencing their biological functions. However, the specific effects of yak follicular fluid exosomes on 2-hydroxyestrodiol (2-OHE2) secretion remain unknown. Here, we investigated whether yak follicular fluid exosomes can increase 2-OHE2 secretion through the activation of autophagy in cumulus cells (YCCs). In vitro cultured YCCs were treated with yak follicular fluid exosomes for 6, 12, and 24 h. The effects of yak follicular fluid exosomes on autophagy and 2-OHE2 secretion were evaluated through real-time quantitative fluorescence PCR (RT-qPCR), Western blotting (WB), transfected with RFP-GFP-LC3, immunohistochemistry, and ELISA. To further investigate whether 2-OHE2 secretion was related to autophagy, YCCs were administered with yak follicular fluid exosomes, 3-methyladenine (3-MA), and rapamycin (RAPA). The results revealed that treatment with yak follicular fluid exosomes activated autophagy in YCCs and increased 2-OHE2 secretion. Conversely, the inhibition of autophagy with 3-MA blocked these effects, suggesting that autophagy has an important role in 2-OHE2 secretion in YCCs. Treatment of YCCs with rapamycin showed similar results with yak follicular fluid exosomes as there was an increase in 2-OHE2 secretion due to the activation of autophagy in the treated cumulus cells. Our results demonstrate that autophagy is enhanced by yak follicular fluid exosomes, and this is associated with an increase in 2-OHE2 secretion in YCCs.