Suppr超能文献

β淀粉样蛋白慢性暴露通过内源性大麻素信号失衡促进小胶质细胞的激活状态。

Aβ Chronic Exposure Promotes an Activation State of Microglia through Endocannabinoid Signalling Imbalance.

机构信息

Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Via Vetoio Snc, 67100 L'Aquila, Italy.

European Center for Brain Research-IRCCS Santa Lucia Foundation (FSL), Via del Fosso di Fiorano 64, 00143 Rome, Italy.

出版信息

Int J Mol Sci. 2023 Apr 3;24(7):6684. doi: 10.3390/ijms24076684.

Abstract

Dysfunctional phenotype of microglia, the primary brain immune cells, may aggravate Alzheimer's disease (AD) pathogenesis by releasing proinflammatory factors, such as nitric oxide (NO). The endocannabinoids -arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG) are bioactive lipids increasingly recognised for their essential roles in regulating microglial activity both under normal and AD-driven pathological conditions. To investigate the possible impact of chronic exposure to β-amyloid peptides (Aβ) on the microglial endocannabinoid signalling, we characterised the functional expression of the endocannabinoid system on neonatal microglia isolated from wild-type and Tg2576 mice, an AD-like model, which overexpresses Aβ peptides in the developing brain. We found that Aβ-exposed microglia produced 2-fold more 2-AG than normal microglia. Accordingly, the expression levels of diacylglycerol lipase-α (DAGLα) and monoacylglycerol lipase (MAGL), the main enzymes responsible for synthesising and hydrolysing 2-AG, respectively, were consistently modified in Tg2576 microglia. Furthermore, compared to wild-type cells, transgenic microglia basally showed increased expression of the cannabinoid 2 receptor, typically upregulated in an activated proinflammatory phenotype. Indeed, following inflammatory stimulus, Aβ-exposed microglia displayed an enhanced production of NO, which was abolished by pharmacological inhibition of DAGLα. These findings suggested that exposure to Aβ polarises microglial cells towards a pro-AD phenotype, possibly by enhancing 2-AG signalling.

摘要

小胶质细胞是大脑主要的免疫细胞,其功能障碍表型可能通过释放促炎因子(如一氧化氮 [NO])而加重阿尔茨海默病(AD)的发病机制。内源性大麻素 - 花生四烯酸乙醇胺(AEA)和 2-花生四烯酸甘油(2-AG)是生物活性脂质,越来越多地被认为在调节小胶质细胞活性方面发挥着重要作用,无论是在正常状态还是 AD 驱动的病理状态下。为了研究慢性暴露于 β-淀粉样肽(Aβ)对小胶质细胞内源性大麻素信号转导的可能影响,我们对来自野生型和 Tg2576 小鼠(一种在发育中的大脑中过度表达 Aβ 肽的 AD 样模型)的新生小胶质细胞的内源性大麻素系统的功能表达进行了表征。我们发现,Aβ 暴露的小胶质细胞比正常小胶质细胞产生 2 倍的 2-AG。相应地,二酰基甘油脂肪酶-α(DAGLα)和单酰基甘油脂肪酶(MAGL)的表达水平分别是合成和水解 2-AG 的主要酶,在 Tg2576 小胶质细胞中也被一致修饰。此外,与野生型细胞相比,转基因小胶质细胞基础表达水平增加了大麻素 2 型受体,通常在激活的促炎表型中上调。事实上,与野生型细胞相比,在炎症刺激下,Aβ 暴露的小胶质细胞表现出增强的 NO 产生,而 DAGLα 的药理学抑制则消除了这种产生。这些发现表明,Aβ 暴露会使小胶质细胞向促 AD 表型极化,可能是通过增强 2-AG 信号转导。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验