Khaghani Aylin Jamali, Farrokh Parisa, Zavareh Saeed
School of Biology, Damghan University, Damghan, Iran.
Institute of Biological Sciences, Damghan University, Damghan, Iran.
Int J Reprod Biomed. 2021 Feb 21;19(2):129-136. doi: 10.18502/ijrm.v19i2.8471. eCollection 2021 Feb.
Bisphenol A (BPA), a synthetic endocrine-disrupting chemical, is a reproductive toxicant. Granulosa cells have significant roles in follicle development, and KIT ligand (KITL) and Anti-Müllerian hormone (AMH) are essential biomolecules produced by them during folliculogenesis.
Due to the widespread use of BPA and its potential epigenetic effects, this study examined the impact of BPA on promoter methylation of and genes in mouse granulosa cells.
Preantral follicles were isolated from ovaries of immature mice and cultured for eight days. Then, follicles were treated with 50 and 100 μM of BPA, and 0.01% (v/v) ethanol for 24 and 72 hr. Growth and degeneration of follicles and antrum formation were analyzed. The granulosa cells were isolated mechanically, and their extracted DNA was treated with sodium bisulfite. The promoter regions of the and were analyzed with PCR and sequencing.
BPA did not change follicle survival and antrum formation significantly (p = 0.41). However, the culture in the presence of 100 μM BPA had an inhibitory effect on growth. Before BPA treatment, the CpG of the and promoters were unmethylated and partially methylated, respectively. While the percent of 5mC in the promoter reduced at 100 μM of BPA, it did not alter the promoter methylation.
BPA at higher concentrations has an inhibitory effect on follicle growth. Moreover, it seems that the epigenetic impact of BPA restricts to the demethylation of CpG sites.
双酚A（BPA）是一种合成的内分泌干扰化学物质，是一种生殖毒物。颗粒细胞在卵泡发育中起重要作用，KIT配体（KITL）和抗苗勒管激素（AMH）是它们在卵泡发生过程中产生的重要生物分子。
由于BPA的广泛使用及其潜在的表观遗传效应，本研究检测了BPA对小鼠颗粒细胞中 和 基因启动子甲基化的影响。
从未成熟小鼠卵巢中分离出窦前卵泡并培养8天。然后，卵泡分别用50和100μM的BPA以及0.01%（v/v）乙醇处理24和72小时。分析卵泡的生长、退化和腔形成情况。机械分离颗粒细胞，其提取的DNA用亚硫酸氢钠处理。通过PCR和测序分析 和 的启动子区域。
BPA对卵泡存活和腔形成没有显著影响（p = 0.41）。然而，100μM BPA存在下的培养对生长有抑制作用。在BPA处理前， 和 启动子的CpG分别未甲基化和部分甲基化。虽然在100μM BPA时 启动子中5mC的百分比降低，但它没有改变 启动子甲基化。
较高浓度的BPA对卵泡生长有抑制作用。此外，BPA的表观遗传影响似乎仅限于CpG位点的去甲基化。
