title: miR-22 inhibits mouse ovarian granulosa cell apoptosis by targeting SIRT1.
abstract: Granulosa cell (GC) apoptosis has been shown to be involved in follicular atresia, which is a degenerative process in ovarian follicles of mammals. However, the mechanism underlying the regulation of follicular atresia, particularly by microRNAs, is not well known. Real-time PCR (RT-PCR) was used to detect the expression level of miR-22 in healthy follicles (HF), early atretic follicles (EAF), and progressively atretic follicles (PAF). Flow cytometry was performed to assess the apoptosis of mouse granulosa cells (mGCs) treated with miR-22 mimics or negative control (NC) mimics. Regulation of the expression of SIRT1 by miR-22 was evaluated using a luciferase reporter assay system. To investigate the roles of SIRT1 in mGC apoptosis, the endogenous SIRT1 gene in mGCs was knocked down using an siRNA specific for SIRT1. miR-22 was increased during follicular atresia and suppressed granulosa cell apoptosis. The results of the luciferase reporter assay indicated that SIRT1 was a target gene of miR-22. In addition, knockdown of SIRT1 attenuated apoptosis in mGCs. miR-22 inhibits mGC apoptosis by downregulating SIRT1 directly in vitro. This study provides important insights into understanding the regulation mechanism of ovarian follicle atresia.
authors.affiliation: Procreation and Medicine Centre, Wuxi Maternal and Child Health Hospital, Wuxi 214002, China xiongfane@163.com.
authors.forename: Fang
authors.initials: F
authors.lastname: Xiong
authors.affiliation: Procreation and Medicine Centre, Wuxi Maternal and Child Health Hospital, Wuxi 214002, China.
authors.forename: Lingqing
authors.initials: L
authors.lastname: Hu
authors.affiliation: Procreation and Medicine Centre, Wuxi Maternal and Child Health Hospital, Wuxi 214002, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Procreation and Medicine Centre, Wuxi Maternal and Child Health Hospital, Wuxi 214002, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Xiao
authors.affiliation: Procreation and Medicine Centre, Wuxi Maternal and Child Health Hospital, Wuxi 214002, China.
authors.forename: Juxia
authors.initials: J
authors.lastname: Xiao
keywords: Apoptosis; Follicle atresia; Granulosa cell; SIRT1; miR-22