Qin Yulan, Li Ting, Zhao Hui, Mao Zhanrui, Ding Chunxia, Kang Yani
School of Biomedical Engineering, Bio-ID Center, Shanghai Jiao Tong University, Shanghai, China.
Department of Obstetrics and Gynecology, Yuncheng Central Hospital, Yuncheng, China.
Front Genet. 2021 Mar 8;12:620241. doi: 10.3389/fgene.2021.620241. eCollection 2021.
Polycystic ovary syndrome (PCOS) is a prevalent heterogeneous endocrine and metabolic disorder in women of reproductive age. Epigenetic mechanisms contribute to the development of PCOS. Nevertheless, the role of DNA methylation in the development of PCOS remains unclear. To investigate the molecular mechanisms underlying the hyperandrogenic phenotype of PCOS, dihydrotestosterone (DHT)-induced prenatally androgenized (PNA) mice were used to mimic this phenotype. Ovarian samples from PNA and control mice were subjected to methyl-CpG-binding domain (MBD)-seq and RNA-seq, and validation was conducted using methylation-specific polymerase chain reaction (MSP) and quantitative real-time PCR (RT-qPCR). Immunohistochemical analysis (using anti-LC3II antibody) and transmission electron microscopy were conducted using ovarian tissue sections (which included granulosa cells) from PNA and control mice. There were 857 genes with differentially methylated promoter regions and 3,317 differentially expressed genes (DEGs) in the PNA mice compared to the control mice. Downregulation of (which encodes DNA methyltransferase 1), accompanied by global hypomethylation, was observed in the PNA mice compared to the control mice. The promoter regions of (which encodes MEKK1) and (which encodes LC3II) were hypomethylated, accompanied by upregulation of and mRNA expression. The autophagy profiling results showed that LC3II protein expression and autophagosomes were significantly increased in the granulosa cells of PNA mice. Additionally, the mRNA expression of genes related to the mitogen-activated protein kinase (MAPK)/p53 pathway (, , and ) and the autophagy-related gene were significantly increased. DHT could change the DNA methylation and transcription level of and lead to an activation of autophagy in granulosa cells. These observations indicated that the change in autophagy may be driven by MAPK/p53 pathway activation, which may have been caused by DHT-induced transcriptional, and the methylation level changed of the key upstream gene . Our study provides a novel genetic basis and new insights regarding the pathogenesis of PCOS.
多囊卵巢综合征（PCOS）是育龄期女性中一种常见的异质性内分泌和代谢紊乱疾病。表观遗传机制参与了PCOS的发生发展。然而，DNA甲基化在PCOS发生中的作用仍不清楚。为了研究PCOS高雄激素表型的分子机制，采用二氢睾酮（DHT）诱导的产前雄激素化（PNA）小鼠来模拟这种表型。对PNA小鼠和对照小鼠的卵巢样本进行甲基化CpG结合结构域（MBD）测序和RNA测序，并使用甲基化特异性聚合酶链反应（MSP）和定量实时PCR（RT-qPCR）进行验证。使用来自PNA小鼠和对照小鼠的卵巢组织切片（包括颗粒细胞）进行免疫组织化学分析（使用抗LC3II抗体）和透射电子显微镜检查。与对照小鼠相比，PNA小鼠中有857个基因的启动子区域存在差异甲基化，3317个基因差异表达（DEG）。与对照小鼠相比，PNA小鼠中DNA甲基转移酶1（DNMT1）编码基因下调，同时伴有全基因组低甲基化。丝裂原活化蛋白激酶激酶1（MEKK1）编码基因和微管相关蛋白轻链3-II（LC3II）编码基因的启动子区域低甲基化，同时MEKK1和LC3II mRNA表达上调。自噬分析结果显示，PNA小鼠颗粒细胞中LC3II蛋白表达和自噬体显著增加。此外，与丝裂原活化蛋白激酶（MAPK）/p53信号通路相关基因（Bax、p53和Bcl-2）以及自噬相关基因Atg5的mRNA表达显著增加。DHT可改变DNMT1的DNA甲基化和转录水平，并导致颗粒细胞自噬激活。这些观察结果表明，自噬变化可能是由MAPK/p53信号通路激活驱动的，而这可能是由DHT诱导的转录以及关键上游基因DNMT1甲基化水平变化引起的。我们的研究为PCOS的发病机制提供了新的遗传基础和见解。
