Exploring the impact of follicular fluid exosomes on porcine cumulus cell and oocyte function: Regulatory network analysis based on the ENSSSCG00000042788/ssc-miR-504/PDHA1 axis

The development and maturation of mammalian oocytes are crucial stages in reproduction, directly influencing embryo health and the genetic quality of offspring. Follicular fluid serves as the microenvironment for oocyte development, with exosomes playing a key role in regulating the activities of cumulus cells and oocytes. However, the mechanisms governing porcine oocyte maturation remain incompletely understood. In this study, we conducted transcriptomic analysis on cumulus cells cultured with varying exosome concentrations and identified 334 differentially expressed long noncoding RNAs (lncRNAs). Functional enrichment analysis indicated that the differentially expressed lncRNAs may be involved in cumulus cell expansion, oocyte maturation, and embryo development. Through experiments such as transfection of mimics and inhibitor, quantitative Reverse Transcriptase polymerase chain reaction (qRT-PCR), and western blotting (WB), we confirmed that lncRNA ENSSSCG00000042788 (lnc42788) regulates the expression of pyruvate dehydrogenase alpha 1 (PDHA1) by competitively binding to ssc-miR-504 (miR-504), forming a competing endogenous RNA (ceRNA) network. In summary, the lnc42788/miR-504/PDHA1 axis plays a key role in regulating the proliferation, Apoptosis of porcine cumulus cells, and oocyte maturation.

Cumulus cells; Follicular fluid exosomes; Oocyte maturation; PDHA1; ceRNA network; lncRNA.