title: miR-23a and miR-27a promote human granulosa cell apoptosis by targeting SMAD5.
abstract: In mammals, follicular atresia can be partially triggered by granulosa cell apoptosis. However, very little is known about the functions of miRNAs in granulosa cell apoptosis. We previously reported that hsa-mir-23a (miR-23a) and hsa-mir-27a (miR-27a) were highly expressed in the plasma of patients with premature ovarian failure, but the action of these two miRNAs in follicular development was unclear. In this study, we explored the roles of miR-23a and miR-27a in the granulosa cells of women undergoing in vitro fertilization/embryo transfer. Using Hoechst staining, we found that miR-23a and miR-27a promoted apoptosis in human granulosa cells. In addition, the Western blotting results suggested that the miR-23a/miR-27a-mediated apoptosis occurred via the FasL-Fas pathway. Based on the results of a luciferase-reporter assay and quantitative RT-PCR and Western blotting analyses, we found that SMAD5 is a target gene of both miR-23a and miR-27a. Furthermore, knocking down SMAD5 expression increased the rate of apoptosis, as well as the levels of Fas, FasL, cleaved caspase-8, and cleaved caspase-3 protein. Taken together, these data suggest that miR-23a and miR-27a target SMAD5 and regulate apoptosis in human granulosa cells via the FasL-Fas pathway. These findings provide an improved understanding of the mechanisms underlying granulosa cell apoptosis, which could potentially be used for future clinical applications.
authors.affiliation: Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: Mingyue
authors.initials: M
authors.lastname: Nie
authors.affiliation: Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: Song
authors.initials: S
authors.lastname: Yu
authors.affiliation: Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: Sha
authors.initials: S
authors.lastname: Peng
authors.affiliation: Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Fang
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China wanghm@ioz.ac.cn.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Wang
authors.affiliation: Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China xiaokuiyang2012@163.com.
authors.forename: Xiaokui
authors.initials: X
authors.lastname: Yang
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000235:genetics*; D053148:Caspase 3 / Q000235:genetics; D053181:Caspase 8 / Q000235:genetics; D053222:Fas Ligand Protein / Q000235:genetics / Q000502:physiology; D005260:Female; D005307:Fertilization in Vitro; D006107:Granulosa Cells; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D034622:RNA Interference; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D051902:Smad5 Protein / Q000235:genetics*; D014162:Transfection
chemical_list: D053222:Fas Ligand Protein; C552430:MIRN23a microRNA, human; C531388:MIRN27 microRNA, human; D035683:MicroRNAs; C497797:SMAD5 protein, human; D051902:Smad5 Protein; C505407:CASP3 protein, human; C505530:CASP8 protein, human; D053148:Caspase 3; D053181:Caspase 8
keywords: SMAD5; apoptosis; granulosa cells; miR-23a; miR-27a; ovary