PDE4 inhibitor Roflumilast modulates inflammation and lipid accumulation in PCOS mice to improve ovarian function and reduce DHEA-induced granulosa cell apoptosis in vitro.

Abstract

This study was implemented to address the role of Roflumilast in polycystic ovary syndrome (PCOS) as well as to discuss its reaction mechanism in vivo and in vitro. In vivo, mice were administrated with 6 mg dehydroepiandrosterone (DHEA) per 100 g body weight and fed with 60% high fat diet to induce PCOS. The expression of phosphodiesterases 4 (PDE4) was assessed with RT-qPCR. The ovary pathology was observed by hematoxylin and eosin staining and follicles were counted. Enzyme-linked immunosorbent assay was adopted for the estimation of progesterone, testosterone and inflammatory factors and lipid accumulation was observed by Oil Red O staining. With the application of reverse transcription-quantitative PCR (RT-qPCR) and western blot, the messenger RNA (mRNA) and protein expressions of low-density lipoprotein receptor (LDLR) was resolved. In vitro, Cell counting kit-8 and flow cytometry analysis were applied for the assessment of cell proliferation and apoptosis. The proliferation- and apoptosis-related proteins were appraised with western blot. Additionally, the expressions of PDE-4 at both mRNA and protein levels were tested with RT-qPCR and western blot. Here, it was discovered that PDE4 was greatly elevated in PCOS mice and DHEA-induced ovarian granulosa cells (KGN). In PCOS mice, PDE4 was negative correlated with progesterone and had positive correlation with testosterone. Roflumilast could enhanced progesterone expression, increased the number of primary follicles, preantral follicles and antral follicles but reduced testosterone and decreased the number of cystic follicles in PCOS mice. It was also testified that Roflumilast could inhibit the release of inflammatory factors and lipid accumulation in PCOS mice. Besides, the proliferation of DHEA-induced KGN cells was enhanced while the apoptosis was declined by Roflumilast, accompanied by elevated contents of PCNA, Ki67 and antiapoptotic protein Bcl-2. Collectively, Roflumilast inhibited inflammation and lipid accumulation in PCOS mice to improve ovarian function and reduce DHEA-induced granulosa cell apoptosis.