在血管性痴呆症中,氨酸- ангиотензин系统的调节失调
H M Tayler1, O A Skrobot1, D H Baron1
1Dementia Research Group, Bristol Medical School, University of Bristol, Bristol, UK.
Brain pathology (Zurich, Switzerland)
|March 8, 2024
概括
在血管痴呆症白质中,宁-血管素系统 (RAS) 信号发生变化,这与小血管疾病的严重程度有关. 这种失调可能会导致血管痴呆症的发病.
科学领域:
- 神经科学是一个神经科学.
- 心血管研究研究心血管研究
- 病理学 病理学 病理学
背景情况:
- 胺-血管素系统 (RAS) 在调节血流方面发挥着至关重要的作用,包括在大脑中.
- RAS信号的失调与各种形式的痴呆症有关.
- 以脑血管损伤为特征的血管痴呆症,在了解其潜在机制方面提出了重大挑战.
研究的目的:
- 研究血管痴呆症患者白质内RAS信号的特定变化.
- 确定RAS标记物,小血管疾病 (SVD) 严重程度和血管痴呆症中大脑低的关系.
- 为了比较血管痴呆症中的RAS信号与阿尔茨海默病和对照组.
主要方法:
- 在神经病理学上确诊的血管痴呆,阿尔茨海默病,混合痴呆和对照病例中的白质组织中分析RAS成分 (ACE-1,ACE-2,血管酶).
- 使用ELISA和化分析测量ACE-1和ACE-2蛋白水平和酶活性.
- 通过ELISA对血管素 (Ang-II,Ang-III,Ang-(1-7) 的量化.
- 基于SVD严重程度的病例分层和MAG:PLP1比率的评估作为大脑低 perfusion 的标记.
主要成果:
- 在血管痴呆白质中观察到高ACE-1蛋白和活性,以及增加Ang-II和Ang-III水平,与SVD严重程度相关.
- ACE-1和Ang-II水平与MAG:PLP1比率呈反向关系,这表明与大脑低 perfusion 的联系.
- 血管痴呆症患者的前额白质中ACE-2水平增加.
- 与对照组相比,所有痴呆症组的Ang-(1-7) 水平都升高,但与SVD严重程度无关.
- 在阿尔茨海默病的白质中,RAS信号保持不变.
- 在额叶皮质中,血管性痴呆症显示ACE-1降低和ACE-2增加,血管素水平不变.
结论:
- 在血管痴呆患者的白质中,RAS信号显著失调,特别是在SVD严重程度方面.
- 这些白质RAS变化可能在小血管疾病和血管痴呆症的发病过程中发挥作用.
- 白质中的RAS信号似乎在阿尔茨海默病中没有改变.
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