[Relationship between C-C chemokine receptor type 2 and P38 mitogen-activated protein kinase signaling pathway in the spinal cord of rats with bone cancer pain]

Zhonghua Yi Xue Za Zhi. 2018 Jan 23;98(4):289-293. doi: 10.3760/cma.j.issn.0376-2491.2018.04.010.
[Article in Chinese]

Abstract

Objective: To investigate the relationship between C-C chemokine receptor type 2(CCR2) and P38 mitogen-activated protein kinase (P38MAPK) signaling pathway in the spinal cord of rats and further clarify the mechanism of bone cancer pain (BCP). Methods: A total of 92 healthy female SD rats, of which 60 were subjected to behavioral tests using a ciliary mechanical stimulation needle. SD rats were randomly divided into six groups: sham operation group (group S), bone cancer pain group (group B), sham operation + DMSO solvent group (group SD), bone cancer pain + DMSO solvent group (group BD), sham operation + RS102895 CCR2 inhibitor group (group SR), bone cancer pain + RS102895 CCR2 inhibitor group (group BR), and Von Frey was used in the behavioral test. Another 32 SD rats were randomly divided into the following 8 groups (n=4): sham operation group (group S), bone cancer pain 5 d group (group B5), bone cancer pain 9 d group (group B9), bone cancer pain 14 d group (group B14), bone cancer pain + DMSO solvent group (group BD), bone cancer pain + RS102895 CCR2 inhibitor 0.5 h group (group BR0.5 h), bone cancer pain + RS102895 CCR2 inhibitor 4 h group (group BR4 h), bone cancer pain + RS102895 CCR2 inhibitor 12 h group (group BR12 h). Western blot was used to detect the expression of P38, p-P38 and CCR2 in spinal cord of rats. Results: At day 5, 7, 9, 14, 21 post-injection, mechanical withdrawal thresholds of group S were(30.9±1.5), (31.9±1.2), (32.0±1.1), (31.6±1.5), (32.2±1.4)g respectively, the mechanical withdrawal thresholds of group B were( 26.4±0.7), (24.4±0.8), (21.4±0.8), (13.5±0.4), (9.9±0.2)g respectively, the mechanical withdrawal thresholds in group B decreased obviously versus group S, and the differences were statistically significant(t=-13.177, -16.660, -23.778, -35.574, -48.401, all P<0.01). At day 9 post-injection, the mechanical withdrawal thresholds in SD, BD, SR and BR groups were (32.4±1.7), (19.4±1.1), (32.1±1.3), (26.3±1.0) g respectively, the difference was statistically significant (F=224.681, P<0.01), and the mechanical withdrawal thresholds in group BD decreased obviously versus group SD, while the mechanical withdrawal thresholds in group BR increased obviously versus group BD. The expression levels of p-P38 in spinal cord of group S, group B5, group B9 and group B14 were(0.08±0.03), (0.20±0.05), (0.40±0.17), (0.65±0.14)respectively, the expression levels of CCR2 were(0.08±0.04), (0.18±0.05), (0.30±0.09), (0.58±0.07)respectively, the difference was statistically significant(F=19.123, 40.746, all P<0.01), and the expression of p-P38 and CCR2 in group B9 were showed a significant up-regulation versus group S. The expression levels of p-P38 in spinal cord of group BD, group BR0.5 h, group BR4 h and group BR12 h were (0.57±0.06), (0.17±0.11), (0.03±0.01), (0.25±0.11)respectively, and the difference was statistically significant(F=29.582, P<0.01). The expression of p-P38 in group BR0.5 h, BR4 h, BR12 h showed a significant down-regulation versus group BD. Conclusion: CCR2 in the spinal cord may be involved in the development of bone cancer pain by activating P38MAPK signaling pathway in rats.

目的:探讨骨癌痛大鼠脊髓趋化因子受体2(CCR2)与P38丝裂原活化蛋白激酶(P38MAPK)信号通路的关系,进一步明确骨癌痛的发生机制。 方法:健康雌性SD大鼠共92只,其中60只利用纤毛机械刺激针方法用于行为学试验,采用随机数字表法分为以下6组(n=10):假手术组(S组)、骨癌痛组(B组)、假手术+二甲亚砜(DMSO)溶剂组(SD组)、骨癌痛+DMSO组(BD组)、假手术+RS102895 CCR2抑制剂组(SR组)、骨癌痛+RS102895 CCR2抑制剂组(BR组)。另外32只SD大鼠采用随机数字表法分为以下8组(n=4):假手术组(S组)、骨癌痛5 d组(B5组)、骨癌痛9 d组(B9组)、骨癌痛14 d组(B14组)、骨癌痛+DMSO溶剂组(BD组)、骨癌痛+RS102895 CCR2抑制剂后0.5 h组(BR0.5 h组)、骨癌痛+RS102895 CCR2抑制剂后4 h组(BR4h组)、骨癌痛+RS102895 CCR2抑制剂后12 h组(BR12 h组),通过蛋白质印迹法(Western Blot)检测大鼠脊髓P38蛋白、磷酸化的P38(p-P38)和CCR2的表达水平。 结果: S组造模后5、7、9、14、21 d的机械缩足反应阈值分别为(30.9±1.5)、(31.9±1.2)、(32.0±1.1)、(31.6±1.5)、(32.2±1.4)g,B组分别为(26.4±0.7)、(24.4±0.8)、(21.4±0.8)、(13.5±0.4)、(9.9±0.2)g,与S组比较,B组造模后5、7、9、14、21 d时机械痛阈值降低,差异均有统计学意义(t=-13.177、-16.660、-23.778、-35.574、-48.401,均P<0.01)。造模后第9天,SD组、BD组、SR组和BR组给药后4 h机械缩足反应阈值分别为(32.4±1.7)、(19.4±1.1)、(32.1±1.3)、(26.3±1.0)g,差异有统计学意义(F=224.681,P<0.01);与SD组比较,BD组机械痛阈值降低;与BD组比较,BR组机械痛阈值升高。S组、B5组、B9组、B14组大鼠脊髓p-P38表达水平分别为(0.08±0.03)、(0.20±0.05)、(0.40±0.17)、(0.65±0.14),CCR2表达水平分别为(0.08±0.04)、(0.18±0.05)、(0.30±0.09)、(0.58±0.07),差异均有统计学意义(F=19.123、40.746,均P<0.01);与S组比较,B9组大鼠脊髓p-P38和CCR2表达上调。造模后第9天,BD组、BR0.5 h组、BR4 h组和BR12 h组大鼠脊髓p-P38表达水平分别为(0.57±0.06)、(0.17±0.11)、(0.03±0.01)、(0.25±0.11),差异有统计学意义(F=29.582,P<0.01);与BD组比较,BR0.5 h组、BR4 h组、BR12 h组大鼠脊髓p-P38表达明显下调。 结论:脊髓CCR2可能通过激活P38MAPK信号通路参与了大鼠骨癌痛痛觉过敏的发生。.

Keywords: P38 mitogen-activated protein kinases; Pain; Receptors, chemokine.

MeSH terms

  • Animals
  • Cancer Pain*
  • Female
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Chemokine
  • Spinal Cord
  • p38 Mitogen-Activated Protein Kinases

Substances

  • Receptors, Chemokine
  • p38 Mitogen-Activated Protein Kinases