Yao Xiaolei, Zhang Guomin, Guo Yixuan, Ei-Samahy Mohamed, Wang Shuting, Wan Yongjie, Han Le, Liu Zifei, Wang Feng, Zhang Yanli
Jiangsu Engineering Technology Research Center of Mutton Sheep and Goat Industry, Nanjing Agricultural University, Nanjing 210095, PR China.
Jiangsu Engineering Technology Research Center of Mutton Sheep and Goat Industry, Nanjing Agricultural University, Nanjing 210095, PR China.
Theriogenology. 2017 Oct 15;102:162-173. doi: 10.1016/j.theriogenology.2017.08.002. Epub 2017 Aug 3.
This study aimed to investigate the expression of the vitamin D receptor (VDR) in goat follicles and to determine the effects of Vit D supplementation on goat granulosa cells (GCs) function linked to follicular development. The results demonstrated that VDR was prominently localized in GCs, with expression increasing with follicle diameter. Addition of Vit D (1α,25-(OH)VD; 10 nM) to GCs caused an increase in VDR and in steroidogenic acute regulator (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) mRNA expression. Additionally, Vit D increased the cyclic adenosine monophosphate (cAMP), estradiol (E), and progesterone (P) levels, while it decreased anti-müllerian hormone receptor (AMHR) and follicle-stimulating hormone receptor (FSHR) mRNA expression (P < 0.05). Addition of FSH remarkably increased E P, and cAMP levels (P < 0.05), and Vit D further enhanced the E and cAMP levels in the presence of FSH (P < 0.05). Vit D significantly induced the mRNA expression of CDK4 and CyclinD1, and downregulated P21 gene expression (P < 0.05). In addition, Vit D significantly decreased reactive oxygen species (ROS) production and increased the mRNA and protein expression of superoxide dismutase 2 (SOD2) and catalase (CAT) (P < 0.05). In conclusion, VDR is expressed in GCs of the goat ovaries and Vit D might play an important role in GCs proliferation by regulating cellular oxidative stress and cell cycle-related genes. Meanwhile, Vit D enhances the E and P output of GCs by regulating the expression of 3β-HSD and StAR and the level of cAMP, which regulate steroidogenesis, supporting a potential role for Vit D in follicular development.
本研究旨在调查维生素D受体（VDR）在山羊卵泡中的表达，并确定补充维生素D对与卵泡发育相关的山羊颗粒细胞（GCs）功能的影响。结果表明，VDR主要定位于颗粒细胞中，其表达随卵泡直径增加而升高。向颗粒细胞中添加维生素D（1α,25-（OH）VD；10 nM）导致VDR以及类固醇生成急性调节蛋白（StAR）和3β-羟基类固醇脱氢酶（3β-HSD）mRNA表达增加。此外，维生素D增加了环磷酸腺苷（cAMP）、雌二醇（E）和孕酮（P）水平，同时降低了抗苗勒管激素受体（AMHR）和促卵泡激素受体（FSHR）mRNA表达（P<0.05）。添加促卵泡激素（FSH）显著增加了E、P和cAMP水平（P<0.05），并且在存在FSH的情况下，维生素D进一步提高了E和cAMP水平（P<0.05）。维生素D显著诱导细胞周期蛋白依赖性激酶4（CDK4）和细胞周期蛋白D1（CyclinD1）的mRNA表达，并下调P21基因表达（P<0.05）。此外，维生素D显著降低活性氧（ROS）的产生，并增加超氧化物歧化酶2（SOD2）和过氧化氢酶（CAT）的mRNA和蛋白表达（P<0.05）。总之，VDR在山羊卵巢颗粒细胞中表达，维生素D可能通过调节细胞氧化应激和细胞周期相关基因在颗粒细胞增殖中发挥重要作用。同时，维生素D通过调节3β-HSD和StAR的表达以及cAMP水平来增强颗粒细胞的E和P分泌，这些调节类固醇生成，支持维生素D在卵泡发育中的潜在作用。
