Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56126 Pisa, Italy.
Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, University of Exeter, Exeter EX2 5DW, UK.
Genes (Basel). 2021 May 12;12(5):720. doi: 10.3390/genes12050720.
Altered mitochondrial DNA (mtDNA) methylation has been detected in several human pathologies, although little attention has been given to neurodegenerative diseases. Recently, altered methylation levels of the mitochondrial displacement loop (D-loop) region, which regulates mtDNA replication, were observed in peripheral blood cells of Alzheimer's disease and amyotrophic lateral sclerosis patients. However, nothing is yet known about D-loop region methylation levels in peripheral blood of Parkinson's disease (PD) patients. In the current study, we investigated D-loop methylation levels and mtDNA copy number in peripheral blood of 30 PD patients and 30 age- and sex-matched control subjects. DNA methylation analyses have been performed by means of methylation-sensitive high-resolution melting (MS-HRM) and pyrosequencing techniques, while mtDNA copy number was analyzed by quantitative PCR. MS-HRM and pyrosequencing analyses provided very similar D-loop methylation levels in PD patients and control subjects, and no differences between the two groups have been observed. Treatment with L-dopa and duration of the disease had no effect on D-loop methylation levels in PD patients. Additionally, mtDNA copy number did not differ between PD patients and control subjects. Current results suggest that D-loop methylation levels are not altered in peripheral blood of PD patients nor influenced by dopaminergic treatment.
线粒体 DNA（mtDNA）甲基化的改变已在多种人类病理中被检测到，尽管很少关注神经退行性疾病。最近，在阿尔茨海默病和肌萎缩侧索硬化症患者的外周血细胞中观察到线粒体置换环（D 环）区域的甲基化水平改变，该区域调节 mtDNA 复制。然而，目前尚不清楚帕金森病（PD）患者外周血中的 D 环区域甲基化水平。在本研究中，我们研究了 30 名 PD 患者和 30 名年龄和性别匹配的对照者外周血中的 D 环甲基化水平和 mtDNA 拷贝数。通过甲基化敏感高分辨率熔解（MS-HRM）和焦磷酸测序技术进行 DNA 甲基化分析，而 mtDNA 拷贝数则通过定量 PCR 进行分析。MS-HRM 和焦磷酸测序分析在 PD 患者和对照组中提供了非常相似的 D 环甲基化水平，两组之间没有观察到差异。PD 患者的 L-多巴治疗和疾病持续时间对 D 环甲基化水平没有影响。此外，PD 患者和对照组之间的 mtDNA 拷贝数没有差异。目前的结果表明，PD 患者外周血中的 D 环甲基化水平没有改变，也不受多巴胺能治疗的影响。
