Department of Genetics, The University of Texas MD Anderson Cancer Center, 77030, Houston, TX, USA.
Baylor College of Medicine, 77030, Houston, TX, USA.
Sci Rep. 2024 Nov 4;14(1):26612. doi: 10.1038/s41598-024-74487-1.
The transcription repressor REST in the dorsal root ganglion (DRG) is upregulated by peripheral nerve injury and promotes the development of chronic pain. However, the genes targeted by REST in neuropathic pain development remain unclear. The expression levels of four opioid receptor genes (Oprm1, Oprd1, Oprl1 and Oprk1) and the cannabinoid CB1 receptor (Cnr1) gene in the DRG regulate nociception. In this study, we determined the role of REST in controlling their expression in the DRG induced by spared nerve injury (SNI). SNI induced chronic pain hypersensitivity in wild-type mice and was accompanied by increased levels of Rest transcript and protein. Transcriptomic analyses of wild-type mouse DRGs suggested that SNI upregulates the expression of Rest transcripts and downregulates the transcripts of all four opioid receptor genes and the Cnr1 gene. Quantitative reverse transcription polymerase chain reaction analyses of these tissues validated these results. Analysis of publicly available bioinformatic data suggested that REST binds to the promoter regions of Oprm1 and Cnr1. Chromatin immunoprecipitation analyses indicated the presence of REST at these promoters. Full-length Rest conditional knockout in primary sensory neurons reduced SNI-induced pain hypersensitivity and rescued the SNI-induced reduction in the expression of Oprd1 and Cnr1 in mouse DRG. Our results suggest that nerve injury represses the transcription of at least the Oprd1 and Cnr1 genes via REST in primary sensory neurons and that REST is a potential therapeutic target for neuropathic pain. Thus, inhibiting REST activity could potentially reduce chronic neuropathic pain and augment opioid/cannabinoid analgesic actions by increasing the transcription of Oprd1 and Cnr1 genes in DRG neurons.
背根神经节(DRG)中的转录抑制因子 REST 在外周神经损伤时上调,并促进慢性疼痛的发展。然而,REST 作用于神经病理性疼痛发展的靶基因仍不清楚。四种阿片受体基因(Oprm1、Oprd1、Oprl1 和 Oprk1)和大麻素 CB1 受体(Cnr1)在 DRG 中的表达水平调节伤害感受。在这项研究中,我们确定了 REST 在控制 spared nerve injury(SNI)诱导的 DRG 中这些基因表达中的作用。SNI 在野生型小鼠中诱导慢性疼痛过敏,并伴有 Rest 转录本和蛋白水平的增加。野生型小鼠 DRG 的转录组分析表明,SNI 上调了 Rest 转录本的表达,下调了所有四种阿片受体基因和 Cnr1 基因的转录本。对这些组织的定量逆转录聚合酶链反应分析验证了这些结果。对公开可用的生物信息学数据的分析表明,REST 结合到 Oprm1 和 Cnr1 的启动子区域。染色质免疫沉淀分析表明 REST 存在于这些启动子上。在初级感觉神经元中进行全长 Rest 条件性敲除可降低 SNI 诱导的疼痛过敏,并挽救 SNI 诱导的小鼠 DRG 中 Oprd1 和 Cnr1 表达减少。我们的结果表明,神经损伤通过初级感觉神经元中的 REST 抑制至少 Oprd1 和 Cnr1 基因的转录,并且 REST 是治疗神经病理性疼痛的潜在靶点。因此,抑制 REST 活性可能通过增加 DRG 神经元中 Oprd1 和 Cnr1 基因的转录,从而降低慢性神经病理性疼痛并增强阿片类/大麻素的镇痛作用。