Abstract：
BACKGROUND: Peripheral neuropathic pain (NeP), induced by surgical intervention, is a well-known complication or sequela that remains a clinical challenge with few effective treatments. Ideal animal models that can recapitulate surgery-associated NeP remain to be established for both mechanistic studies and drug discovery.
OBJECTIVE: We aimed to establish a new rat model of postsurgical NeP and describe its characteristics, as well as screen-promising therapeutic analgesics.
METHODS: Experimental research in rats.
METHODS: The research took place in the laboratory of Xinqiao Hospital of the Third Military Medical University.
METHODS: To mimic the surgical procedure associated with peripheral nerve injury (PNI), we established a transient compression injury (TCI) in the sciatic nerve. Behavioral tests of nociception were used to confirm the effect and the time course of this pain model. Histological assessments (transmission electron microscopy evaluation and immunohistochemistry) were performed to observe the neuropathological and immunological features. RNA sequencing (RNA-seq) of injured nerves and dorsal root ganglia (DRGs) was conducted to reveal the underlying mechanism in the newly established animal model and screen promising therapeutic targets.
RESULTS: We established a rat model of TCI of the PN and detected nociceptive hypersensitivity of the injured (ipsilateral) nerve by behavioral tests. This animal model of NeP was further confirmed by observing time-dependent changes in mechanical allodynia and thermal hyperalgesia, as well as by examining the activation of microglia in the ipsilateral spinal dorsal horn. Pathophysiologically, TCI induced macroscopic nerve swelling and demyelination, which resulted in inflammatory responses in ipsilateral nerves. We also found inflammatory cell infiltration in the ipsilateral nerve that was sustained for several weeks, which further exacerbated local inflammation and oxidative stress. Moreover, RNA-seq revealed remarkably upregulated inflammatory reactions in PNs and the DRGs. Notably, the overexpression of inflammatory mediators and the infiltration of macrophages and microglia triggered remote immune responses in DRGs. Based on the RNA-seq results, we also confirmed that gabapentin (GBP) exerts therapeutic effects in TCI-induced NeP by regulating alpha2delta-1.
CONCLUSIONS: We did not compare the new rat model with the classical pain model (like chronic constriction injury or spared nerve injury) in histology or transcriptomics.
CONCLUSIONS: We established a new rat model of NeP and thoroughly characterized neuroinflammation in the injured nerve and DRGs. Based on the upregulated genes in DRGs in this model, we screened a promising analgesic (GBP) capable of reducing pain hypersensitivity in surgery-associated NeP.
OBJECTIVE: We aimed to establish a new rat model of postsurgical NeP and describe its characteristics, as well as screen-promising therapeutic analgesics.
METHODS: Experimental research in rats.
METHODS: The research took place in the laboratory of Xinqiao Hospital of the Third Military Medical University.
METHODS: To mimic the surgical procedure associated with peripheral nerve injury (PNI), we established a transient compression injury (TCI) in the sciatic nerve. Behavioral tests of nociception were used to confirm the effect and the time course of this pain model. Histological assessments (transmission electron microscopy evaluation and immunohistochemistry) were performed to observe the neuropathological and immunological features. RNA sequencing (RNA-seq) of injured nerves and dorsal root ganglia (DRGs) was conducted to reveal the underlying mechanism in the newly established animal model and screen promising therapeutic targets.
RESULTS: We established a rat model of TCI of the PN and detected nociceptive hypersensitivity of the injured (ipsilateral) nerve by behavioral tests. This animal model of NeP was further confirmed by observing time-dependent changes in mechanical allodynia and thermal hyperalgesia, as well as by examining the activation of microglia in the ipsilateral spinal dorsal horn. Pathophysiologically, TCI induced macroscopic nerve swelling and demyelination, which resulted in inflammatory responses in ipsilateral nerves. We also found inflammatory cell infiltration in the ipsilateral nerve that was sustained for several weeks, which further exacerbated local inflammation and oxidative stress. Moreover, RNA-seq revealed remarkably upregulated inflammatory reactions in PNs and the DRGs. Notably, the overexpression of inflammatory mediators and the infiltration of macrophages and microglia triggered remote immune responses in DRGs. Based on the RNA-seq results, we also confirmed that gabapentin (GBP) exerts therapeutic effects in TCI-induced NeP by regulating alpha2delta-1.
CONCLUSIONS: We did not compare the new rat model with the classical pain model (like chronic constriction injury or spared nerve injury) in histology or transcriptomics.
CONCLUSIONS: We established a new rat model of NeP and thoroughly characterized neuroinflammation in the injured nerve and DRGs. Based on the upregulated genes in DRGs in this model, we screened a promising analgesic (GBP) capable of reducing pain hypersensitivity in surgery-associated NeP.
摘要：
背景：周围神经性疼痛（NeP），由手术干预引起，是一种众所周知的并发症或后遗症，仍然是一个临床挑战，几乎没有有效的治疗方法。可以概括手术相关NeP的理想动物模型仍有待建立，用于机理研究和药物发现。
目的：我们旨在建立一种新的大鼠术后NeP模型，并描述其特征，以及屏幕有前途的治疗镇痛药。
方法：大鼠实验研究。
方法：本研究在第三军医大学新桥医院实验室进行。
方法：为了模拟与周围神经损伤（PNI）相关的外科手术，我们建立了坐骨神经短暂性压迫损伤（TCI）。使用伤害感受的行为测试来确认该疼痛模型的效果和时程。进行组织学评估（透射电子显微镜评估和免疫组织化学）以观察神经病理学和免疫学特征。进行了损伤神经和背根神经节（DRGs）的RNA测序（RNA-seq），以揭示新建立的动物模型中的潜在机制并筛选有希望的治疗靶标。
结果：我们建立了PN的TCI大鼠模型，并通过行为测试检测了受损（同侧）神经的伤害性敏感性。通过观察机械性痛觉异常和热痛觉过敏的时间依赖性变化，进一步证实了NeP的动物模型。以及通过检查同侧脊髓背角小胶质细胞的激活。病理生理学，TCI引起的宏观神经肿胀和脱髓鞘，导致同侧神经的炎症反应。我们还在同侧神经中发现了持续数周的炎性细胞浸润，这进一步加剧了局部炎症和氧化应激。此外，RNA-seq显示PNs和DRGs的炎症反应显著上调。值得注意的是,炎症介质的过度表达以及巨噬细胞和小胶质细胞的浸润触发了DRGs中的远程免疫应答。根据RNA-seq结果,我们还证实加巴喷丁（GBP）通过调节α2δ-1在TCI诱导的NeP中发挥治疗作用。
结论：我们没有在组织学或转录组学上比较新的大鼠模型与经典疼痛模型（如慢性收缩性损伤或备用神经损伤）。
结论：我们建立了一种新的NeP大鼠模型，并彻底表征了损伤神经和DRGs中的神经炎症。基于该模型中DRGs中上调的基因，我们筛选了一种有前景的镇痛剂(GBP),能够减轻手术相关NeP的疼痛敏感性.
目的：我们旨在建立一种新的大鼠术后NeP模型，并描述其特征，以及屏幕有前途的治疗镇痛药。
方法：大鼠实验研究。
方法：本研究在第三军医大学新桥医院实验室进行。
方法：为了模拟与周围神经损伤（PNI）相关的外科手术，我们建立了坐骨神经短暂性压迫损伤（TCI）。使用伤害感受的行为测试来确认该疼痛模型的效果和时程。进行组织学评估（透射电子显微镜评估和免疫组织化学）以观察神经病理学和免疫学特征。进行了损伤神经和背根神经节（DRGs）的RNA测序（RNA-seq），以揭示新建立的动物模型中的潜在机制并筛选有希望的治疗靶标。
结果：我们建立了PN的TCI大鼠模型，并通过行为测试检测了受损（同侧）神经的伤害性敏感性。通过观察机械性痛觉异常和热痛觉过敏的时间依赖性变化，进一步证实了NeP的动物模型。以及通过检查同侧脊髓背角小胶质细胞的激活。病理生理学，TCI引起的宏观神经肿胀和脱髓鞘，导致同侧神经的炎症反应。我们还在同侧神经中发现了持续数周的炎性细胞浸润，这进一步加剧了局部炎症和氧化应激。此外，RNA-seq显示PNs和DRGs的炎症反应显著上调。值得注意的是,炎症介质的过度表达以及巨噬细胞和小胶质细胞的浸润触发了DRGs中的远程免疫应答。根据RNA-seq结果,我们还证实加巴喷丁（GBP）通过调节α2δ-1在TCI诱导的NeP中发挥治疗作用。
结论：我们没有在组织学或转录组学上比较新的大鼠模型与经典疼痛模型（如慢性收缩性损伤或备用神经损伤）。
结论：我们建立了一种新的NeP大鼠模型，并彻底表征了损伤神经和DRGs中的神经炎症。基于该模型中DRGs中上调的基因，我们筛选了一种有前景的镇痛剂(GBP),能够减轻手术相关NeP的疼痛敏感性.
