Karl-Schöller Franziska, Kunz Meik, Kreß Luisa, Held Melissa, Egenolf Nadine, Wiesner Anna, Dandekar Thomas, Sommer Claudia, Üçeyler Nurcan
Department of Neurology, University of Würzburg, Josef-Schneider-Str. 11, 97080 Würzburg, Germany.
Department of Bioinformatics, Biocenter University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
Exp Neurol. 2022 Jan;347:113915. doi: 10.1016/j.expneurol.2021.113915. Epub 2021 Nov 7.
Neuropathic pain occurs in more than half of the patients suffering from peripheral neuropathies. We investigated the role of microRNA (miR)-21 in neuropathic pain using a murine-human translational approach. We applied the spared nerve injury (SNI) model at the sciatic nerve of mice and assessed the potential analgesic effect of perineurial miR-21-5p inhibitor application. Immune-related targets of miR-21-5p were determined by a qRT-PCR based cytokine and chemokine array. Bioinformatical analysis identified potential miR-21-5p targets interacting with CC-chemokine ligand (CCL)5. We validated CCL5 and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein (YWHAE), an interaction partner of miR-21-5p and CCL5, by qRT-PCR in murine common peroneal and tibial nerves. Validated candidates were then investigated in white blood cell and sural nerve biopsy samples of patients with focal to generalized pain syndromes, i.e. small fiber neuropathy (SFN), polyneuropathy (PNP), and nerve lesion (NL). We showed that perineurial miR-21-5p inhibition reverses SNI-induced mechanical and heat hypersensitivity in mice and found a reduction of the SNI-induced increase of the pro-inflammatory mediators CCL5 (p < 0.01), CCL17 (p < 0.05), and IL-12ß (p < 0.05) in miR-21-5p inhibitor-treated mice. In silico analysis revealed several predicted and validated targets for miR-21-5p with CCL5 interaction. Among these, we found lower YWHAE gene expression in mice after SNI and perineurial injections of a scrambled oligonucleotide compared to naïve mice (p < 0.05), but this was not changed by miR-21-5p inhibition. Furthermore, miR-21-5p inhibition led to a further increase of the SNI-induced increase in TGFß (p < 0.01). Patient biomaterial revealed different systemic expression patterns of miR-21-5p, with higher expression in SFN and lower expression in NL. Further, we showed higher systemic expression of pro-inflammatory mediators in white blood cells of SFN patients compared to healthy controls. We have conducted a translational study comparing results from animal models to human patients with three different neuropathic pain syndromes. We identified CCL5 as a miR-21 dependent common player in the mouse SNI model and the human painful disease SFN.
超过半数的外周神经病变患者会出现神经性疼痛。我们采用鼠 - 人转化研究方法，探究了微小RNA（miR）-21在神经性疼痛中的作用。我们在小鼠坐骨神经上应用 spared nerve injury（SNI）模型，并评估了神经束膜 miR-21-5p 抑制剂应用的潜在镇痛效果。通过基于 qRT-PCR 的细胞因子和趋化因子阵列确定了 miR-21-5p 的免疫相关靶点。生物信息学分析确定了与 CC 趋化因子配体（CCL）5 相互作用的潜在 miR-21-5p 靶点。我们通过 qRT-PCR 在小鼠腓总神经和胫神经中验证了 CCL5 以及 miR-21-5p 与 CCL5 的相互作用伙伴酪氨酸 3-单加氧酶/色氨酸 5-单加氧酶激活蛋白（YWHAE）。然后在患有局灶性至全身性疼痛综合征的患者的白细胞和腓肠神经活检样本中研究了已验证的候选物，即小纤维神经病变（SFN）、多发性神经病变（PNP）和神经损伤（NL）。我们发现神经束膜 miR-21-5p 抑制可逆转小鼠 SNI 诱导的机械性和热超敏反应，并发现 miR-21-5p 抑制剂处理的小鼠中，SNI 诱导的促炎介质 CCL5（p < 0.01）、CCL17（p < 0.05）和 IL-12ß（p < 0.05）的增加有所减少。计算机分析揭示了几个预测和验证的 miR-21-5p 与 CCL5 相互作用的靶点。其中，我们发现与未处理的小鼠相比，SNI 后经神经束膜注射乱序寡核苷酸的小鼠中 YWHAE 基因表达较低（p < 0.05），但 miR-21-5p 抑制对此无改变。此外，miR-21-5p 抑制导致 SNI 诱导的 TGFß 增加进一步升高（p < 0.01）。患者生物材料显示 miR-21-5p 存在不同的全身表达模式，在 SFN 中表达较高，在 NL 中表达较低。此外，我们发现与健康对照相比，SFN 患者白细胞中促炎介质的全身表达更高。我们进行了一项转化研究，比较了动物模型与患有三种不同神经性疼痛综合征的人类患者的结果。我们确定 CCL5 是小鼠 SNI 模型和人类疼痛疾病 SFN 中 miR-21 依赖性的共同作用因子。
