Targeting the host metabolome to reverse drug-induced epigenetic changes

项目摘要 病理性物质使用障碍是一组毁灭性的精神疾病，其特点是 不断升级和失控的药物摄取，以及经常持续的戒断和复发循环。其中一个 物质使用障碍翻译性研究的关键问题是如何接触滥用药物 导致这种动机行为模式的持续失调。染色质的长期变化 结构是物质使用中出现的持续的基因表达和行为失调的基础 精神错乱。对染色质结构的调节需要整合来自 环境，而且有强有力的文献表明，关键代谢物和辅因子的水平 调节染色质动力学。值得注意的是，几乎所有修饰组蛋白或DNA的酶都利用关键代谢物 作为其催化活性的底物或辅因子。因此，关键代谢物的可用性直接影响到 细胞改变染色质结构的能力。我们的初步研究表明，反复接触药物 滥用会显著改变血清和大脑代谢物。许多失调的代谢物是那些 已知是表观遗传写入者和擦除者功能的关键辅助因素。与此平行的是，涉及的基因 在细胞代谢的调节中，伏隔核在延长时间后仍有明显变化 戒烟。综上所述，这些数据表明代谢组是一种针对表观遗传学的新手段。 对药物使用障碍的监管。初步研究将利用药物自我给药和恢复 与血清和脑代谢组学相结合，进一步确定与药物摄入量和 寻找毒品。后续研究将确定代谢物信号的操纵如何改变行为 反应和脑表观遗传学。通过限制饮食或代谢产物的系统性操作 补充将阐明这些代谢物在行为上的作用，以及细胞特异性的基因操作 关键的代谢酶将为观察到的效果增加特异性和清晰度。新陈代谢操作将会是 结合细胞特异性染色质图谱通过ATAC-测序、定量质谱学来鉴定 组蛋白修饰和染色质相关蛋白复合体的变化，以检查 行为效应和表观遗传效应的相互作用。最后，我们将利用尖端的转基因小鼠 在关键代谢物结合位点的表观遗传编写器/擦除器中创建可诱导点突变的技术 评估当阻止酶-代谢物相互作用时对行为和染色质结构的影响。 这些研究将定义一个新的研究领域，以物质使用中染色质的代谢调节为目标 并将确定新的翻译研究目标，这些目标将显著增加我们对 物质使用障碍的表观遗传调控。

Project Summary Pathological substance use disorders are a set of devastating psychiatric conditions marked by a pattern of escalating and out of control drug intake and an often-persistent cycle of withdrawal and relapse. One of the critical questions for translational research on substance use disorders is how exposure to drugs of abuse leads to such persistent dysregulation in patterns of motivated behaviors. Long-lasting changes to chromatin structure underlie the persistent dysregulation of gene expression and behavior seen in substance use disorders. Regulation of chromatin structure requires the integration of a myriad of signals from the environment, and there is a robust literature demonstrating that levels of key metabolites and cofactors regulate chromatin dynamics. Notably, nearly all enzymes that modify histones or DNA utilize key metabolites as substrates or cofactors in their catalytic activity. Therefore, availability of key metabolites directly affects the ability of a cell to make alter chromatin structure. Our preliminary studies show that repeated exposure to drugs of abuse markedly alters the serum and brain metabolome. Many of the dysregulated metabolites are those known to be critical cofactors for the function of epigenetic writers and erasers. Parallel to this, genes involved in the regulation of cellular metabolism in the nucleus accumbens were markedly altered even after prolonged withdrawal. Taken together, these data identify the metabolome as a novel means to target epigenetic regulation in substance use disorders. Initial studies will utilize drug self-administration and reinstatement coupled with serum and brain metabolomics to further identify metabolites that correlate with drug intake and drug seeking. Subsequent studies will determine how manipulations of metabolite signaling alter behavioral response and brain epigenetics. Systemic manipulation of metabolites via dietary restriction or supplementation will clarify the role of these metabolites on behavior, and cell-specific gene manipulations of key metabolic enzymes will add specificity and clarity to observed effects. Metabolic manipulations will be coupled with cell-specific chromatin profiling via ATAC-sequencing, quantitative mass spectrometry to identify changes in histone modifications, and chromatin-associated protein complexes in order to examine the interaction of behavioral and epigenetic effects. Finally, we will utilize cutting edge transgenic mouse technology to create inducible point mutations in epigenetic writers/erasers at key metabolite binding sites to assess the effects on behavior and chromatin structure when enzyme-metabolite interactions are prevented. These studies will define a new field of research targeting metabolic regulation of chromatin in substance use disorders and will identify novel translational research targets that will markedly increase our understanding of epigenetic regulation in substance use disorders.