Sun Wei, Zhang Yajun, Roy Snehashis, Williams Avram Sarah K, Sun Ching-Yu, Petros Timothy J, Amara Susan G
Laboratory of Molecular and Cellular Neurobiology (LMCN), NIMH.
Unit on Cellular and Molecular Neurodevelopment, NICHD.
bioRxiv. 2025 Jul 31:2025.07.28.667272. doi: 10.1101/2025.07.28.667272.
Methamphetamine profoundly alters the function of midbrain dopaminergic neurons, yet the molecular mechanisms underlying these effects are not fully understood. Using single-nucleus RNA sequencing, we found that acute methamphetamine exposure leads to a marked up-regulation of cholesterol metabolism genes in dopaminergic neurons of the ventral tegmental area and substantia nigra-a response that was much less pronounced in astrocytes and largely absent in other cell types. Further analysis using a ribosome tagging strategy combined with RNA sequencing revealed that amphetamine, a structurally similar psychostimulant, induced similar gene expression changes, whereas methylphenidate, a structurally distinct psychostimulant, did not, highlighting drug-specific transcriptional responses. Notably, repeated methamphetamine exposure resulted in down-regulation of cholesterol metabolism genes in dopaminergic neurons. Interestingly, we also observed that, compared to neighboring cell types, dopaminergic neurons are highly enriched in genes encoding cholesterol biosynthesis enzymes, including the rate-limiting enzyme , and key regulators and , challenging the prevailing view that neurons rely mainly on astrocyte-derived cholesterol. In summary, our study highlights dynamic changes in cholesterol metabolism in dopaminergic neurons in response to amphetamines and uncovers the potential importance of cholesterol homeostasis for dopaminergic neuron function.
甲基苯丙胺会深刻改变中脑多巴胺能神经元的功能,然而这些作用背后的分子机制尚未完全明确。通过单核RNA测序,我们发现急性甲基苯丙胺暴露会导致腹侧被盖区和黑质多巴胺能神经元中胆固醇代谢基因显著上调——这种反应在星形胶质细胞中不太明显,在其他细胞类型中基本不存在。使用核糖体标签策略结合RNA测序的进一步分析表明,结构相似的精神兴奋剂苯丙胺会诱导类似的基因表达变化,而结构不同的精神兴奋剂哌甲酯则不会,这突出了药物特异性转录反应。值得注意的是,反复暴露于甲基苯丙胺会导致多巴胺能神经元中胆固醇代谢基因下调。有趣的是,我们还观察到,与相邻细胞类型相比,多巴胺能神经元中编码胆固醇生物合成酶的基因高度富集,包括限速酶以及关键调节因子和,这对神经元主要依赖星形胶质细胞衍生胆固醇的主流观点提出了挑战。总之,我们的研究突出了多巴胺能神经元中胆固醇代谢对苯丙胺的动态变化反应,并揭示了胆固醇稳态对多巴胺能神经元功能的潜在重要性。