趋化因子CXCL10作为神经病理性疼痛生物标记物的研究

目的:目前临床上缺乏神经病理性疼痛诊断和预后判断的客观指标,本研究旨在检测神经病理性疼痛小鼠和人的脑脊液(cerebrospinal fluid,CSF)和血清中趋化因子CXCL10的表达情况。方法:结扎ICR小鼠L5脊神经(spinal nerve ligation,SNL)构建神经病理性疼痛(neuropathic pain,NP)模型,足底注射福尔马林或完全弗氏佐剂(complete Freund's adjuvant,CFA)建立炎症性疼痛模型;收集捐献者的脑脊液和血液,采用Real-time PCR、半定量PCR、Western Blot、免疫荧光和ELISA方法,分别检测CXCL10和CXCR3的mRNA和蛋白表达、CSF和血清中CXCL10的表达。结果:①Cxcl10在正常ICR小鼠的脾脏、淋巴结、背根神经节(dorsal root ganglion,DRG)、脊髓和脑中有不同程度的基础表达;②Cxcr3在正常ICR小鼠的脾脏、淋巴结、DRG、脊髓和脑中也有不同程度的基础表达;③与假手术组相比,SNL模型小鼠CSF与血清中CXCL10含量显著增加(P<0.05,P<0.01);急性炎症性疼痛小鼠CSF和血清中CXCL10与对照组相比无显著变化;慢性炎症性疼痛小鼠CSF中CXCL10与对照组相比无显著变化;血清中CXCL10显著增加(P<0.05);④健康人类受试者的脊髓、DRG和淋巴结中有CXCL10和CXCR3表达;⑤疱疹后神经痛病人CSF与血清中CXCL10与对照组相比显著增加(P<0.05),骨性关节炎病人CSF和血清中CXCL10无显著增加。结论:神经病理性小鼠CSF和血清以及疱疹后神经痛病人CSF和血清中CXCL10表达显著增加,CXCL10可能作为神经病理性疼痛的生物标志物。

A study of chemokine CXCL10 as a biomarker of neuropathic pain

Objective:The objective biomarkers for the diagnosis and prognosis of neuropathic pain are still lacking.The aim of this study was to determine CXCL10 levels in the serum and cerebrospinal fluid(CSF)in mice and human and to evaluate whether CXCL10 can be used as a biomarker in neuropathic pain.Methods:The neuropathic pain(NP)was established by L5 spinal nerve ligation(SNL)of ICR mice.Inflammatory pain was induced by injection of formalin or complete Freund's adjuvant(CFA)in the hind paw.The mRNA expression of CXCL10 and CXCR3 in distinct tissues was assessed by real-time PCR(RT-PCR)and semi-quantitative PCR,and the protein expression was detected by immunofluorescence or western blotting(WB).CXCL10 levels in the serum and CSF were tested by ELISA.Results:①Cxcl10 is expressed at different levels in spleen,lymph nodes,dorsal root ganglion(DRG),spinal cord,and brain of adult ICR mice;②Cxcr3 is expressed at different levels in spleen,lymph nodes,DRG,spinal cord,and brain of adult ICR mice;③Compared with the sham group,the CXCL10 content in the CSF and serum of SNL mice was significantly increased(P<0.05,P<0.01);CXCL10 in CSF and serum of mice with acute inflammatory pain had no significant change compared with that of control group;Compared with the control group,the serum CXCL10 of mice with chronic inflammatory pain was significantly increased(P<0.05),but there was no change in CSF;④The expression of CXCL10 and CXCR3 was observed in DRG,spinal cord and lymph node of healthy subjects;⑤The levels of CXCL10 in CSF and serum were elevated in patients with postherpetic pain(P<0.05),but not in patients with osteoarthritis.Conclusion:Our results indicated that the CXCL10 content was significantly increased in serum or CSF of both mouse and human experiencing neuropathic pain.Thus,CXCL10 may serve as a possible objective diagnostic and/or prognostic marker of neuropathic pain.