Department of Laboratory Medicine, Medical University of Gdańsk, Ul. Dębinki 7, 80-211, Gdańsk, Poland.
Neurochem Res. 2013 Aug;38(8):1523-42. doi: 10.1007/s11064-013-1060-x. Epub 2013 May 16.
Glucose-derived pyruvate is a principal source of acetyl-CoA in all brain cells, through pyruvate dehydogenase complex (PDHC) reaction. Cholinergic neurons like neurons of other transmitter systems and glial cells, utilize acetyl-CoA for energy production in mitochondria and diverse synthetic pathways in their extramitochondrial compartments. However, cholinergic neurons require additional amounts of acetyl-CoA for acetylcholine synthesis in their cytoplasmic compartment to maintain their transmitter functions. Characteristic feature of several neurodegenerating diseases including Alzheimer's disease and thiamine diphosphate deficiency encephalopathy is the decrease of PDHC activity correlating with cholinergic deficits and losses of cognitive functions. Such conditions generate acetyl-CoA deficits that are deeper in cholinergic neurons than in noncholinergic neuronal and glial cells, due to its additional consumption in the transmitter synthesis. Therefore, any neuropathologic conditions are likely to be more harmful for the cholinergic neurons than for noncholinergic ones. For this reason attempts preserving proper supply of acetyl-CoA in the diseased brain, should attenuate high susceptibility of cholinergic neurons to diverse neurodegenerative conditions. This review describes how common neurodegenerative signals could induce deficts in cholinergic neurotransmission through suppression of acetyl-CoA metabolism in the cholinergic neurons.
葡萄糖衍生的丙酮酸是所有脑细胞中乙酰辅酶 A 的主要来源,通过丙酮酸脱氢酶复合物(PDHC)反应。与其他递质系统的神经元和神经胶质细胞一样,胆碱能神经元在其线粒体和细胞外隔室的各种合成途径中利用乙酰辅酶 A 进行能量产生。然而,胆碱能神经元需要额外的乙酰辅酶 A 用于细胞质隔室中的乙酰胆碱合成,以维持其递质功能。包括阿尔茨海默病和焦磷酸硫胺素缺乏性脑病在内的几种神经退行性疾病的特征是 PDHC 活性下降,与胆碱能缺陷和认知功能丧失相关。由于在递质合成中额外消耗,这些条件会导致乙酰辅酶 A 缺乏,在胆碱能神经元中比在非胆碱能神经元和神经胶质细胞中更为严重。因此,任何神经病理条件对胆碱能神经元的危害都可能比对非胆碱能神经元的危害更大。出于这个原因,尝试在患病大脑中保持适当的乙酰辅酶 A 供应,应该可以减轻胆碱能神经元对各种神经退行性疾病的高度敏感性。这篇综述描述了常见的神经退行性信号如何通过抑制胆碱能神经元中的乙酰辅酶 A 代谢来诱导胆碱能神经传递缺陷。