Activin A overexpression promotes rat follicular development through SCF-kit-mediated cell signals

Abstract

We explored the possible signaling pathway by which activin A induces oocyte maturation. Inhba-overexpressing lentivirus vectors were constructed and transfected into primary granulosa cells in vitro and ovary tissues in vivo in rats. The granulosa cell growth curve was drawn, and antibodies for phospho-Smad2, phospho-Erk5, phospho-Nur77, and stem cell factor (SCF) were prepared for western blot analysis. Protein expression of SCF and C-kit in the rat ovaries was detected by immunohistochemical staining. The rate of granulosa cell proliferation was higher in the Inhba gene overexpression group (INH) than in the control groups (CON group and GFP group) in vitro. Protein expression of SCF and C-kit was higher in the INH group than in the other two groups. phospho-Smad2, phospho-ERK5, P-nur77, and SCF proteins showed positive expression in rat ovarian granulosa cells in each group and were obviously increased in the INH group. Activin A overexpression may promote rat granulosa cell proliferation through Smad2/ERK5/nur77 signaling pathways, and rat granulosa cells overexpressing activin A in vitro showed increased levels of SCF and c-kit proteins.

摘要

我们探讨了激活素A诱导卵母细胞成熟的信号通路。构建抑制素β A亚基基因（Inhba）过表达的慢病毒载体, 转染到大鼠体外原代颗粒细胞和体内的卵巢组织内。绘制颗粒细胞的生长曲线, 准备磷酸化-Smad2、磷酸化-Erk5、磷酸化-Nur77和干细胞因子（stem cell factor, SCF）抗体进行Western Blot分析。免疫组化染色检测大鼠卵巢SCF和C-kit蛋白表达。Inhba基因过表达组（INH）的颗粒细胞增殖率高于对照组（CON组和GFP组）。INH组SCF和C-kit蛋白表达高于其他两组。各组大鼠卵巢颗粒细胞中磷酸化-Smad2、磷酸化-Erk5、磷酸化-Nur77、SCF蛋白均呈阳性表达, 在INH组中表达明显升高。过表达激活素A可通过Smad2/ERK5/nur77信号通路促进大鼠颗粒细胞的增殖, 体外过表达激活素A的大鼠颗粒细胞SCF和C-kit蛋白水平升高。

Keywords:

• Activin A
• follicular development
• granulosa cell
• gene transfection

Disclosure statement

All authors declare that they have no conflict of interest.

Additional information

Funding

This study was supported by the Health and Family Planning Commission of Shandong Province (2016WS0127).