Department of Hand Surgery, Yantaishan Hospital, Yantai, Shandong 264000, P.R. China.
Department of Orthopedics, Zaozhuang Hospital of Zaozhuang Mining Group, Zaozhuang, Shandong 277100, P.R. China.
Int J Mol Med. 2021 Feb;47(2):561-572. doi: 10.3892/ijmm.2020.4824. Epub 2020 Dec 16.
The aim of the present study was to investigate the effects of microRNA (miR)‑142‑3p on neuropathic pain caused by sciatic nerve injury in chronic compression injury (CCI) rats, and further investigate its mechanism. Rat experiments were divided into four parts in the study. In the first part, the rats were divided into the Sham and CCI groups. The expression of miR‑142‑3p, AC9 and cAMP were detected. In the second part, the rats were divided into the Sham, CCI, miR‑142‑3p mimic, mimic‑negative control (NC), miR‑142‑3p small interfering RNA (siRNA) and siRNA‑NC groups. The expression of cAMP and the levels of AMPK pathway‑related proteins were detected. In the third part, the rats were randomly divided into Sham, CCI, AC9 mimic, mi‑NC, AC9 siRNA and si‑NC groups. Double luciferase reporter assay was used to analyse the targeting relationship between miR‑142‑3p and AC9. In the fourth part, the rats were divided into the Sham, CCI, miR‑142‑3p siRNA, AC9 mimic, miR‑142‑3p siRNA + AC9 siRNA, cAMP activator (Forskolin) and miR‑142‑3p siRNA + cAMP inhibitor groups. The expression of miR‑142‑3p was significantly increased while AC9 and cAMP expression significantly decreased in CCI rats. However, AC9 overexpression significantly increased the levels of cAMP protein. Luciferase reporter assay also proved that AC9 is the target gene of miR‑142‑3p. Moreover, miR‑142‑3p silencing was found to reduce neuropathic pain in CCI rats by upregulating the expression of AC9. It was also found that cAMP activation can relieve neuropathic pain and promote the expression of AMPK‑related proteins in CCI rats. Silencing miR‑142‑3p can target AC9 to reduce the expression of inflammatory factors and neuropathic pain in CCI rats by increasing the expression of cAMP/AMPK pathway‑related proteins.
本研究旨在探讨微小 RNA（miR）-142-3p 对慢性压迫性损伤（CCI）大鼠坐骨神经损伤所致神经性疼痛的影响，并进一步探讨其机制。大鼠实验分为四个部分。在第一部分，大鼠分为假手术（Sham）和 CCI 组。检测 miR-142-3p、AC9 和 cAMP 的表达。在第二部分，大鼠分为 Sham、CCI、miR-142-3p 模拟物、模拟物阴性对照（NC）、miR-142-3p 小干扰 RNA（siRNA）和 siRNA-NC 组。检测 cAMP 的表达和 AMPK 通路相关蛋白的水平。在第三部分，大鼠随机分为 Sham、CCI、AC9 模拟物、mi-NC、AC9 siRNA 和 si-NC 组。双荧光素酶报告基因分析用于分析 miR-142-3p 与 AC9 的靶向关系。在第四部分，大鼠分为 Sham、CCI、miR-142-3p siRNA、AC9 模拟物、miR-142-3p siRNA+AC9 siRNA、cAMP 激活剂（forskolin）和 miR-142-3p siRNA+cAMP 抑制剂组。CCI 大鼠中 miR-142-3p 表达明显增加，而 AC9 和 cAMP 表达明显降低。然而，AC9 的过表达显著增加了 cAMP 蛋白的水平。荧光素酶报告基因分析也证明 AC9 是 miR-142-3p 的靶基因。此外，miR-142-3p 的沉默通过上调 AC9 的表达减轻 CCI 大鼠的神经性疼痛。还发现 cAMP 的激活可以缓解 CCI 大鼠的神经性疼痛，并促进 AMPK 相关蛋白的表达。沉默 miR-142-3p 可以通过增加 cAMP/AMPK 通路相关蛋白的表达来靶向 AC9，从而降低 CCI 大鼠的炎症因子和神经性疼痛的表达。
