DNA 甲基化可通過調節基因轉錄水平的表達改變，在突觸重塑、神經前體細胞分化等神經生物過程中起重要作用。近年來，不斷有研究發現，DNA 甲基化與癲癇密切相關。文章主要探討 DNA 甲基化參與癲癇發病的可能機制，以及為 DNA 甲基化提供甲基的甲硫氨酸循環在癲癇發病機制中的調控作用，以期為癲癇的預防和治療提供新思路。
DNA 甲基化是人類發現最早的表觀遺傳學修飾之一，具有多種調控功能，參與機體發育過程中干細胞生長、細胞增殖、器官發育、衰老和腫瘤發生等多個生物學過程，而且在突觸重塑、神經細胞分化等神經生物過程中也具有重要作用。近年來，越來越多的研究表明 DNA 甲基化修飾與癲癇的發病機制密切相關，特別是基因啟動子的甲基化改變逐漸受到關注。文章主要對表觀遺傳中基因啟動子區的甲基化在癲癇發生發展中的研究進展進行綜述。
ObjectiveTo investigate the difference of DNA methylation before and after bariatric surgery.MethodThe relevant literatures of the research on the changes of DNA methylation level and gene expression regulation in blood and tissues before and after bariatric surgery were retrieved and reviewed.ResultsDNA methylation was an important method of epigenetic regulation in organisms and its role in bariatric surgery had been paid more and more attention in recent years. Existing studies had found that there were changes of DNA methylation in blood and tissues before and after bariatric surgery. The degree of methylation varies with different follow-up time after bariatric surgery and the same gene had different degrees of methylation in different tissues, and some even had the opposite results.ConclusionsDNA methylation levels before and after bariatric surgery are different in different tissues. And studies with larger sample size and longer follow-up time are needed, to further reveal relationship among DNA methylation, obesity, and bariatric surgery.
ObjectiveTo explore the role of DNA methylation in the pathogenesis of cholangiocarcinoma and its progress as a therapeutic target for cholangiocarcinoma.MethodThe relevant literatures at home and abroad in recent years about the DNA methylation and cholangiocarcinoma were reviewed.ResultsMethylation is a frequent event in cholangiocarcinoma and effect the occurrence and development of cholangiocarcinogenesis. DNA methylation inhibitors reactivate tumor suppressor genes.ConclusionsDNA methylation is closely related to the cholangiocarcinogenesis. Despite there is no effective clinical therapeutics and diagnosis at present, with further study, DNA methylation is expected to be one of the new target to treatment and diagnosis this disease.
Objective To examine the expression of promoter CpG island methylation of Notch1 gene and explore the variable sites for DNA methylation in lung CD4 + T cells of asthmatic rat models.Methods An ovalbumin ( OVA) sensitized- challenged asthmatic rat model was established. Total T cells were isolated and CD4 + T lymphocytes were purified using magnetic beads. Twenty Wistar rats were randomly divided into a control group and an asthma group ( n = 10 in each group) . CD4 + T cells were isolated by immunomagnetic beads and identified by flow cytometry ( FCM) . Realtime PCR was employed to examine the mRNA expression of Notch1 gene in lung CD4 + T cells and the methylation level of Notch1 gene was examined by methylation-specific PCR. Results The mRNA expression of Notch1 in lung CD4 + T cells of the asthma group was 2. 254 ±0. 403 times as much as that of the control group. The total methylation level of asthma group was lower than that of the control group ( 0. 150 ±0. 108 vs. 0. 300 ±0. 667, P lt;0. 01) . Conclusion Promoter demethylation is one of the major mechanisms of Notch1 gene up-regulation in pathogenesis of asthma.
