脊髓背角在复杂性区域疼痛综合征 I 型大鼠模型中的表达谱分析揭示了潜在的介导疼痛和神经炎症反应的机制。

Expression profiling of spinal cord dorsal horn in a rat model of complex regional pain syndrome type-I uncovers potential mechanisms mediating pain and neuroinflammation responses.

机构信息

Department of Neurobiology and Acupuncture Research, The Third Clinical Medical College, Zhejiang Chinese Medical University, Key Laboratory of Acupuncture and Neurology of Zhejiang Province, 548 Binwen Road, Hangzhou, 310053, China.

Academy of Chinese Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, 310053, China.

出版信息

J Neuroinflammation. 2020 May 23;17(1):162. doi: 10.1186/s12974-020-01834-0.

BACKGROUND

Complex regional pain syndrome type-I (CRPS-I) is a progressive and devastating pain condition. The mechanisms of CRPS-I still remain poorly understood. We aim to explore expression profiles of genes relevant to pain and neuroinflammation mechanisms involved in CRPS-I.

METHODS

The rat chronic post-ischemic pain (CPIP) model that mimics human CRPS-I was established. RNA-sequencing (RNA-Seq), qPCR, Western blot, immunostaining, and pharmacological studies were used for profiling gene changes in ipsilateral spinal cord dorsal horn (SCDH) of CPIP model rat and further validation.

RESULTS

CPIP rats developed persistent mechanical allodynia in bilateral hind paws, accompanied with obvious glial activation in SCDH. RNA-Seq identified a total of 435 differentially expressed genes (DEGs) in ipsilateral SCDH of CPIP rats. qPCR confirmed the expression of several representative genes. Functional analysis of DEGs identified that the most significantly enriched biological processes of upregulated genes include inflammatory and innate immune response. We further identified NLRP3 inflammasome expression to be significantly upregulated in SCDH of CPIP rats. Pharmacological blocking NLRP3 inflammasome reduced IL-1β overproduction, glial activation in SCDH as well as mechanical allodynia of CPIP rats.

CONCLUSION

Our study revealed that immune and inflammatory responses are predominant biological events in SCDH of CPIP rats. We further identified NLRP3 inflammasome in SCDH as a key contributor to the pain and inflammation responses in CPIP rats. Thus, our study provided putative novel targets that may help to develop effective therapeutics against CRPS-I.

背景

复杂性区域疼痛综合征 I 型（CRPS-I）是一种进行性且破坏性的疼痛病症。CRPS-I 的发病机制仍知之甚少。我们旨在探索与疼痛和神经炎症机制相关的基因表达谱，这些机制涉及 CRPS-I。

方法

建立了模拟人类 CRPS-I 的大鼠慢性缺血后疼痛（CPIP）模型。使用 RNA 测序（RNA-Seq）、qPCR、Western blot、免疫染色和药理学研究来分析 CPIP 模型大鼠同侧脊髓背角（SCDH）中的基因变化，并进行进一步验证。

结果

CPIP 大鼠双侧后爪出现持续的机械性痛觉过敏，同时 SCDH 中胶质细胞明显活化。RNA-Seq 在 CPIP 大鼠同侧 SCDH 中共鉴定出 435 个差异表达基因（DEGs）。qPCR 验证了几个代表性基因的表达。DEGs 的功能分析表明，上调基因最显著富集的生物学过程包括炎症和先天免疫反应。我们进一步发现，NLRP3 炎性小体在 CPIP 大鼠 SCDH 中的表达显著上调。药理学阻断 NLRP3 炎性小体可减少 CPIP 大鼠 SCDH 中 IL-1β 的过度产生、胶质细胞活化以及机械性痛觉过敏。