酒精代謝促進大腦組蛋白乙醯化
作者:
小柯機器人發布時間:2019/10/25 11:00:11
美國賓夕法尼亞大學S. L. Berger和G. Egervari等研究人員發現酒精代謝促進大腦組蛋白乙醯化。相關論文於2019年10月23日在線發表於國際學術期刊《自然》。
通過使用小鼠體內的穩定同位素標記,研究人員表明酒精的代謝有助於大腦中組蛋白的快速乙醯化,並且這部分是通過將醇來源的乙醯基(以一種依賴於乙醯輔酶A合成酶2,即ACSS2,的方式)直接沉積到組蛋白中而發生的。當在體內給小鼠注射重標記的乙酸鹽時,觀察到類似的直接沉積。在懷孕的小鼠中,暴露於標記的酒精會導致標記的乙醯基結合到妊娠胎兒的大腦中。在離體的原代海馬神經元中,細胞外乙酸能夠誘導與學習和記憶有關的轉錄程序,這些程序對ACSS2抑制敏感。
研究人員發現酒精相關的聯想學習需要體內ACSS2。這些發現表明,酒精代謝和基因調控之間存在直接聯繫,這是通過大腦中組蛋白的ACSS2依賴性乙醯化來實現的。
新興的證據表明,表觀遺傳調控取決於代謝狀態,並且在驅動行為的神經功能中牽涉特定的代謝因子。在神經元中,組蛋白的乙醯化依賴於代謝物乙醯輔酶A,它是由染色質結合的ACSS2從乙酸鹽產生的。值得注意的是,肝臟中酒精的分解會導致血液中醋酸鹽水平的快速增加,因此酒精是體內醋酸鹽的主要來源。因此,神經元中的組蛋白乙醯化可能受到源自酒精的乙酸鹽的影響,對酒精誘導的大腦中基因表達和行為產生潛在影響。
附:英文原文
Title: Alcohol metabolism contributes to brain histone acetylation
Author: P. Mews, G. Egervari, R. Nativio, S. Sidoli, G. Donahue, S. I. Lombroso, D. C. Alexander, S. L. Riesche, E. A. Heller, E. J. Nestler, B. A. Garcia, S. L. Berger
Issue&Volume: 2019-10-23
Abstract: Emerging evidence suggests that epigenetic regulation is dependent on metabolic state, and implicates specific metabolic factors in neural functions that drive behaviour1. In neurons, acetylation of histones relies on the metabolite acetyl-CoA, which is produced from acetate by chromatin-bound acetyl-CoA synthetase 2 (ACSS2)2. Notably, the breakdown of alcohol in the liver leads to a rapid increase in levels of blood acetate3, and alcohol is therefore a major source of acetate in the body. Histone acetylation in neurons may thus be under the influence of acetate that is derived from alcohol4, with potential effects on alcohol-induced gene expression in the brain, and on behaviour5. Here, using in vivo stable-isotope labelling in mice, we show that the metabolism of alcohol contributes to rapid acetylation of histones in the brain, and that this occurs in part through the direct deposition of acetyl groups that are derived from alcohol onto histones in an ACSS2-dependent manner. A similar direct deposition was observed when mice were injected with heavy-labelled acetate in vivo. In a pregnant mouse, exposure to labelled alcohol resulted in the incorporation of labelled acetyl groups into gestating fetal brains. In isolated primary hippocampal neurons ex vivo, extracellular acetate induced transcriptional programs related to learning and memory, which were sensitive to ACSS2 inhibition. We show that alcohol-related associative learning requires ACSS2 in vivo. These findings suggest that there is a direct link between alcohol metabolism and gene regulation, through the ACSS2-dependent acetylation of histones in the brain.
DOI: 10.1038/s41586-019-1700-7
Source: https://www.nature.com/articles/s41586-019-1700-7