Liu Mingjian, Liu Yu, Li Xuan, Pei Miao, Han Mei, Qi Feng
Department of Anesthesiology and Pain Clinic, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.
Laboratory of Basic Medical Sciences, Qilu Hospital, Shandong University, Jinan, Shandong, China.
Front Pharmacol. 2022 Nov 3;13:1031804. doi: 10.3389/fphar.2022.1031804. eCollection 2022.
Myofascial pain syndrome (MPS) is a chronic pain disorder with inflammation-related primarily characterized by the presence of myofascial trigger points (MTrPs). Myocyte enhancer factor 2C (MEF2C) is involved in the occurrence of a variety of skeletal muscle diseases. However, it is not yet clear if MEF2C is involved in MTrPs. The purpose of this study was to investigate whether MEF2C was involved in the inflammatory pathogenesis of MTrPs. In the present study, we used RNA sequencing (RNA-seq) to compare the differential expression of myocyte enhancer factor 2C (MEF2C) in healthy participants and MTrPs participants. The widely used rat MTrPs model was established to research the upstream and downstream regulatory mechanism of MEF2C and found that MEF2C was significantly increased in patients with MTrPs. Dexmedetomidine (Dex) was injected intramuscularly in the MTrPs animal to assess its effects on MEF2C. The expression of MEF2C protein and mRNA in skeletal muscle of rats in the MTrPs group were up-regulated. In addition, the expression of TNF- α, p-P65, MLCK, and Myocilin (MyoC) was up-regulated and the mechanical pain threshold was decreased. Peripheral TNF- injection significantly decreased the mechanical pain threshold and increased the expression of p-P65, MLCK, MEF2C, and MyoC in healthy rats. Maslinic acid increased the mechanical pain threshold and inhibited the expression of p-P65, MLCK, MEF2C, and MyoC. In addition, peripheral injection of DEX in MTrPs rats also inhibited the expression of TNF- α, p-P65, MLCK, MEF2C, and MyoC. These results suggest that MEF2C is involved in the inflammatory pathogenesis of MTrPs and DEX serves as a potential therapeutic strategy for the treatment of MPS.
肌筋膜疼痛综合征(MPS)是一种主要与炎症相关的慢性疼痛疾病,其主要特征是存在肌筋膜触发点(MTrP)。肌细胞增强因子2C(MEF2C)参与多种骨骼肌疾病的发生。然而,MEF2C是否参与MTrP尚不清楚。本研究的目的是探讨MEF2C是否参与MTrP的炎症发病机制。在本研究中,我们使用RNA测序(RNA-seq)比较健康参与者和MTrP参与者中肌细胞增强因子2C(MEF2C)的差异表达。建立广泛使用的大鼠MTrP模型以研究MEF2C的上下游调控机制,发现MTrP患者中MEF2C显著增加。在MTrP动物中肌肉注射右美托咪定(Dex)以评估其对MEF2C的影响。MTrP组大鼠骨骼肌中MEF2C蛋白和mRNA的表达上调。此外,TNF-α、p-P65、肌球蛋白轻链激酶(MLCK)和肌纤蛋白(MyoC)的表达上调,机械痛阈降低。外周注射TNF-显著降低健康大鼠的机械痛阈,并增加p-P65、MLCK、MEF2C和MyoC的表达。齐墩果酸提高机械痛阈,并抑制p-P65、MLCK、MEF2C和MyoC的表达。此外,在MTrP大鼠中外周注射DEX也抑制TNF-α、p-P65、MLCK、MEF2C和MyoC的表达。这些结果表明,MEF2C参与MTrP的炎症发病机制,DEX作为治疗MPS的潜在治疗策略。