Oocyte cumulus complex quality and oviduct transportation velocity in systemic autoimmune disease model mice

Oocyte transportation by the oviduct involves the interaction between ciliated epithelial cells and cumulus cells. To determine whether the quality of cumulus-oocyte complexes (COCs) changes the transportation property of COCs, we compared the transportation velocity of COCs (TVC) by the infundibulum ex vivo with various combinations of infundibula and COCs collected from different mice. We used young and aged C57BL/6N and MRL/MpJ, and MRL/MpJ-Fas (lpr/lpr) mice as the strains with intact female reproductive function and the systemic autoimmune disease model exhibiting oocyte pick-up dysfunction owing to the morphofunctional abnormality of ciliated epithelium, respectively. The TVC of aged MRL strains was less than that of aged C57BL/6N mice, suggesting that aging affects the transportation of COCs in MRL strains. The TVC of aged MRL/MpJ-Fas( lpr/lpr ) mice was the least among all examined combinations, whereas the TVC accelerated when the infundibulum or COCs were collected from other strains. These results indicate that the transportation property of COCs is determined not only by the ciliary function in the infundibulum but also by the properties of COCs.

Automated summary

Oocyte transportation in the oviduct is influenced by the interaction between ciliated epithelial cells and cumulus cells. In this study, we investigated the effect of cumulus-oocyte complex (COC) quality on the transportation property of COCs by comparing the transportation velocity of COCs (TVC) in different combinations of infundibula and COCs collected from various mice. Our results showed that the TVC was lower in aged MRL strains compared to aged C57BL/6N mice, indicating that aging affects COCs transportation in MRL strains. Moreover, the TVC was the lowest in aged MRL/MpJ-Fas (lpr/lpr) mice, while it accelerated when the infundibulum or COCs were collected from other strains, suggesting that the properties of COCs also play a role in determining their transportation property.