Effects of moxibustion on serum IL-6, IL-8 and TNF-α in rats with experimental rheumatoid arthritis

艾灸对实验性类风湿性关节炎大鼠血清IL-6、IL-8及TNF-α的影响

Objective:To observe the effects of moxibustion on serum levels of interleukin(IL)-6,IL-8 and tumor necrosis factor-α(TNF-α),and to explore the effects of moxibustion on inflammatory damaging factors in experimental rheumatoid arthritis(RA)model rats;the relationship between the therapeutic effect of moxibustion on RA and the change in the Toll-like receptor(TLR)signaling pathway was analyzed using Toll-like receptor 4(TLR4)antagonists and agonists.Methods:Fifty Sprague-Dawley(SD)rats were divided into a normal group,a model group,a moxibustion group,a moxibustion plus TLR4 agonist group(agonist group)and a moxibustion plus TLR4 antagonist group(antagonist group)according to the random number table,with 10 rats in each group.Except the normal group,rats in the other four groups were subjected to model preparation with the wind,cold and wet environmental factors plus Freund's complete adjuvant(FCA).Rats in the normal and model groups were not treated;rats in the moxibustion,agonist and antagonist groups started to be treated with the moxibustion(cigarette-type moxa)at bilateral Shenshu(BL 23)and Zusanli(ST 36)from the 4th day after the successful modeling,for 20 min each time with a total of 10 d.Rats in the agonist and the antagonist groups were injected with TLR4 agonist or antagonist[0.1 mg/(kg*bw)]via the tail vein 30 min before moxibustion.The concentrations of serum IL-6,IL-8 and TNF-αin each group were determined by enzyme-linked immunosorbent assay(ELISA).Results:Compared with the normal group,in the model group,the rat's right hind paw swelling was significantly obvious(P<0.01);there was a lot of inflammatory infiltration in the synovial tissues,the surface of the synovial membrane was unsmooth,the synovial membrane was hyperplasia and thicker,and the serum IL-6,IL-8 and TNF-αconcentrations increased significantly(P<0.05).Compared with the model group,the paw swelling degrees of the rats in the moxibustion,the agonist and the antagonist groups reduced significantly(all P<0.01);the swelling degree in the antagonist group was milder than that in the agonist group,but the between-group difference was not statistically significant(P>0.05);inflammatory infiltration and synovial membrane hyperplasia in the synovial tissues of the moxibustion group and the antagonist group were all relieved differently;the decrease of synovial layer number in the moxibustion group was more obvious,and there were no obvious improvements in inflammatory infiltration and synovial thickness in the agonist group;the concentrations of IL-6,IL-8 and TNF-αin the moxibustion group were decreased,and the differences in the IL-6 and TNF-αconcentrations were statistically significant(all P<0.01);there was no significant between-group difference in the IL-8 concentration(P>0.05);the concentrations of serum IL-8 and TNF-αin the agonist group increased significantly(both P<0.01),while the IL-6 concentration decreased without significant difference(P>0.05);the concentrations of IL-6 and IL-8 in the antagonist group decreased but the between-group differences were statistically insignificant(both P>0.05);and the TNF-αconcentration significantly increased(P<0.05).Compared with the moxibustion group,IL-6,IL-8 and TNF-αconcentrations increased in the agonist group,and the differences in the IL-8 and TNF-αconcentrations were statistically significant(both P<0.01);the concentrations of IL-6,IL-8 and TNF-αincreased in the antagonist group,and the differences in the IL-6 and TNF-αconcentrations were statistically significant(both P<0.01);there was no significant difference in the IL-8 concentration between the groups(P>0.05).The serum levels of IL-6,IL-8 and TNF-αin the antagonist group were lower than those in the agonist group(all P<0.05).Conclusion:Moxibustion at Shenshu(BL 23)and Zusanli(ST 36)can reduce the joint swelling degree and inflammation in synovial tissue of RA model rats,decrease the serum levels of IL-6,IL-8 and TNF-αin RA model rats;the decreases of IL-6 and TNF-αare more significant than the decrease of IL8;TLR4 agonist and antagonist can significantly attenuate the effect of moxibustion in inhibiting releases of IL-6,IL-8 and TNF-α,so that the change in TLR signaling pathway affects the effect of moxibustion in inhibiting the releases of IL-6,IL-8 and TNF-α.

目的:观察艾灸对实验性类风湿性关节炎(RA)模型大鼠血清中白细胞介素(IL)-6、IL-8和肿瘤坏死因子α(TNF-α)含量的变化,探讨艾灸对RA模型大鼠相关炎性致损因子的干预作用;通过应用Toll样受体4(TLR4)拮抗剂和激动剂,分析艾灸对RA的治疗作用与Toll样受体信号通路变化之间的关系。方法:将50只Sprague-Dawley(SD)大鼠根据随机数字表分为正常组、模型组、艾灸组、艾灸加TLR4激动剂组(激动剂组)和艾灸加TLR4拮抗剂组(拮抗剂组),每组10只。除正常组外,其余4组大鼠采用风、寒、湿环境因素+弗氏完全佐剂(FCA)复合造模。正常组和模型组不作治疗;艾灸组、激动剂组和拮抗剂组于造模成功后第4天开始用香烟型艾条灸双侧腎俞和足三里,每穴每次灸20 min,共灸10 d。激动剂组和拮抗剂组分别在艾灸前30 min经尾静脉注射TLR4激动剂或拮抗剂[0.1 mg/(kg-bw)]。采用酶联免疫吸附(ELISA)法测定各组大鼠血清IL-6、IL-8和TNF-ct的浓度。结果:与正常组比较,模型组大鼠右后肢肿胀明显(P<0.01),滑膜组织中有大量炎性浸润表现,滑膜表面不整齐,滑膜增生变厚;血清IL-6、IL-8和TNF-α浓度均显著升高(均P<0.05)。与模型组比较,艾灸组、激动剂组和拮抗剂组大鼠的足趾肿胀程度均明显减轻(P<0.01),拮抗剂组肿胀程度轻于激动剂组,但组间差异无统计学意义(P>0.05);艾灸组和拮抗剂组滑膜组织中炎性浸润和滑膜增生变厚现象不同程度缓解,其中艾灸组滑膜层数减少最明显,激动剂组的炎性浸润和滑膜厚度缓解不明显。艾灸组IL-6、IL-8和TNF-α浓度均下降,其中IL-6和TNFV浓度的组间差异有统计学意义(均P<0.01),IL-8浓度的组间差异无统计学意义(P>0.05);激动剂组大鼠血清IL-8和TNF-α的浓度均显著上升(均P<0.01),而IL-6下降,但组间差异无统计学意义(P>0.05);拮抗剂组IL-6和IL-8浓度均降低,但组间差异无统计学意义(P>0.05),TNF-α浓度升高,组间差异有统计学意义(P<0.05)。与艾灸组比较,激动剂组IL-6、IL-8和TNF-α均升高,其中IL-8和TNF-α浓度的组间差异有统计学意义(均P<0.01);拮抗剂组IL-6、IL-8和TNF-α浓度均升高,其中IL-6和TNF-α浓度的组间差异有统计学意义(均P<0.01),IL-8浓度的组间差异无统计学意义(P>0.05)。拮抗剂组大鼠血清IL-6、IL-8和TNF-α浓度均低于激动剂组(均P<0.05)。结论:艾灸肾俞和足三里可减轻RA模型大鼠足趾肿胀和滑膜炎症,降低血清中IL-6、IL-8和TNF-α浓度,且IL-6和TNF-α的浓度下降较IL-8更为显著;TLR4激动剂和拮抗剂介入艾灸治疗能显著减弱艾灸抑制IL-6、IL-8和TNF-α释放的作用,TLR信号通路的变化影响艾灸抑制IL-6、IL-8和TNF-α释放的作用。