Xie Xiao-Juan, Ma Li-Gang, Xi Kai, Fan Dong-Mei, Li Jian-Guo, Zhang Quan, Zhang Wei
1 Department of Anesthesia, First Affiliated Hospital, College of Clinical Medicine of Henan University of science and technology, Luoyang, China.
2 Department of ENT, First Affiliated Hospital, College of Clinical Medicine of Henan University of science and technology, Luoyang, China.
Mol Pain. 2017 Jan-Dec;13:1744806917706582. doi: 10.1177/1744806917706582.
Objective To investigate the effects of microRNA-223 on morphine analgesic tolerance by targeting NLRP3 in a rat model of neuropathic pain. Methods Our study selected 100 clean grade healthy Sprague-Dawley adult male rats weighing 200 to 250 g. After establishment of a rat model of chronic constriction injury, these rats were divided into 10 groups (10 rats in each group): the normal control, sham operation, chronic constriction injury, normal saline, morphine, miR-223, NLRP3, miR-223 + morphine, NLRP3 + morphine, and miR-223 + NLRP3 + morphine groups. The real-time quantitative polymerase chain reaction assay, Western blotting, and enzyme-linked immunosorbent assay were used for detecting the mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, Interleukin (IL)-1β, and IL-18 in sections of lumbar spinal cord. Immunohistochemistry was applied for detecting the positive rates of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1β, and IL-18. Results The paw withdrawal threshold and percentage maximum possible effect (%MPE) were higher in chronic constriction injury group when compared with the normal control and sham operation groups. Behavioral tests showed that compared with the chronic constriction injury and normal saline groups, the morphine and miR-223 + morphine groups showed obvious analgesic effects. Expressions of miR-223 in the miR-223, miR-223 + morphine, and miR-223 + NLRP3 + morphine were significantly higher than those in the chronic constriction injury, normal saline, and morphine groups. Compared with chronic constriction injury, normal saline and morphine groups, the mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1β, and IL-18 were significantly decreased in the miR-223 and miR-223 + morphine groups, while mRNA and protein expressions of NLRP3, apoptosis-associated speck-like protein, Caspase-1, IL-1β, and IL-18 were significantly increased in the NLRP3 and NLRP3 + morphine group. Conclusion Our study provides strong evidence that miR-223 could suppress the activities of NLRP3 inflammasomes ( NLRP3, apoptosis-associated speck-like protein, and Caspase-1) to relieve morphine analgesic tolerance in rats by down-regulating NLRP3.
目的 通过靶向NLRP3研究微小RNA-223在神经性疼痛大鼠模型中对吗啡镇痛耐受性的影响。方法 本研究选取100只体重200至250g的清洁级健康成年雄性Sprague-Dawley大鼠。建立大鼠慢性压迫性损伤模型后，将这些大鼠分为10组（每组10只）：正常对照组、假手术组、慢性压迫性损伤组、生理盐水组、吗啡组、miR-223组、NLRP3组、miR-223+吗啡组、NLRP3+吗啡组和miR-223+NLRP3+吗啡组。采用实时定量聚合酶链反应检测、蛋白质印迹法和酶联免疫吸附测定法检测腰段脊髓切片中NLRP3、凋亡相关斑点样蛋白、半胱天冬酶-1、白细胞介素（IL）-1β和IL-18的mRNA和蛋白表达。应用免疫组织化学法检测NLRP3、凋亡相关斑点样蛋白、半胱天冬酶-1、IL-1β和IL-18的阳性率。结果 与正常对照组和假手术组相比，慢性压迫性损伤组的 paw withdrawal threshold 和最大可能效应百分比（%MPE）更高。行为学测试表明，与慢性压迫性损伤组和生理盐水组相比，吗啡组和miR-223+吗啡组表现出明显的镇痛效果。miR-223组、miR-223+吗啡组和miR-223+NLRP3+吗啡组中miR-223的表达明显高于慢性压迫性损伤组、生理盐水组和吗啡组。与慢性压迫性损伤组、生理盐水组和吗啡组相比，miR-223组和miR-223+吗啡组中NLRP3、凋亡相关斑点样蛋白、半胱天冬酶-1、IL-1β和IL-18的mRNA和蛋白表达明显降低，而NLRP3组和NLRP3+吗啡组中NLRP3、凋亡相关斑点样蛋白、半胱天冬酶-1、IL-1β和IL-18的mRNA和蛋白表达明显升高。结论 本研究提供了有力证据表明，miR-223可通过下调NLRP3抑制NLRP3炎性小体（NLRP3、凋亡相关斑点样蛋白和半胱天冬酶-1）的活性，从而减轻大鼠的吗啡镇痛耐受性。
