Decrease of methionine and S-adenosylmethionine and increase of homocysteine in treated patients with Parkinson's disease.
Neuroscience Letters(2001)
摘要
Levodopa is administered with dopa decarboxylase inhibitors (DDI) to prevent its peripheral degradation. This increases conversion of levodopa to 3-O-methyldopa (3-OMD) by catechol-O-methyltransferase (COMT). S-adenosylmethionine (SAM), which is synthesized from adenosintriphosphate and methionine (MET), serves as methyl donor for this O-metabolisation of levodopa with resulting conversion of SAM to total homocysteine (tHcy) via S-adenosylhomocysteine (SAH). Previous studies showed augmented plasma levels of tHcy in long-term levodopa/DDI-treated patients with Parkinson's disease (PP). Objective of this study was to compare MET, SAM, levodopa, 3-OMD, tHcy and SAH in plasma of 20 levodopa/DDI treated PP and corresponding controls. A significant decrease of MET respectively SAM and an increase of tHcy appeared in PP. SAH with its short half-life did not differ. Levodopa/DDI long-term treatment contributes to altered levels of substrates of the O-methylation cycle in PP.
更多查看译文
关键词
Parkinson's disease,Levodopa,Homocysteine
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要