Interplay Between the MicroRNA miR-152 and Quercetin in the Control of Ovarian Granulosa Cell Functions

In the present study, we examined the functional interrelationships between microRNAs and plant polyphenols in the regulation of ovarian cell functions. For this purpose, we compared the basic functions of porcine ovarian granulosa cells with or without transfection with miR-152 mimics that were cultured with or without quercetin. The expression levels of miR-152, cell viability, cell proliferation (accumulation of proliferating cell nuclear antigen, PCNA), apoptosis (accumulation of Bax) and the release of progesterone, estradiol, and insulin-like growth factor I (IGF-I) were analyzed by real-time quantitative polymerase chain reaction (RT‒qPCR), the Trypan blue exclusion test, quantitative immunocytochemistry, and enzyme-linked immunosorbent assays (ELISAs). Transfection of cells with miR-152 mimics increased miR-152 expression, reduced cell viability, proliferation, apoptosis, and estradiol output, and promoted the release of progesterone and IGF-I. Quercetin decreased all measured parameters. Moreover, quercetin promoted the effect of miR-152 on cell viability, apoptosis, and estradiol and mitigated the effect of miR-152 on cell proliferation and IGF-I output. For instance, miR-152 mimics promoted the effect of quercetin on cell viability, apoptosis, and estradiol but prevented the effect of quercetin on PCNA. These observations demonstrated the involvement of miR-152 and quercetin in the control of ovarian cell functions and their functional interrelationships, mainly synergism, in the regulation of these functions.