选择性白细胞介素-6抑制剂Am-80对DA大鼠实验性自身免疫性脑脊髓炎的影响。

Effect of selective IL-6 inhibitor Am-80 on experimental autoimmune encephalomyelitis in DA rats.

作者信息

Wang T, Nagai H, Bouda K, Matsuura S, Takaoka Y, Niwa S, Homma T, Tanaka H, Shudo K

机构信息

Department of Pharmacology, Gifu Pharmaceutical University, Gifu 502, Japan.

出版信息

Acta Pharmacol Sin. 2000 Nov;21(11):967-76.

PMID:11501064

Abstract

AIM

To observe the role of interleukin (IL)-6 in the development of experimental autoimmune encephalomyelitis (EAE).

METHODS

DA rats were immunized by injecting bovine myelin basic protein (MBP). mRNA of cytokines, such as IL-6, IL-10, TNF-alpha, TGF-beta 1, IFN-gamma, and iNOS, were detected by RT-PCR. MBP was injected into ear to induce delayed type cutaneous hypersensitivity response (DTH). Histological studies were performed on the spinal cord with HE staining. Nitric oxide (NO) production from cultured murine macrophage clones was stimulated with LPS plus IFN-gamma.

RESULTS

DA rats developed EAE disease with a peak of severity on d 13 and d 14. Am-80 (1.0, 3.0 mg/kg), a selective IL-6 inhibitor, inhibited the symptoms in terms of deterioration as observed by the clinical score, body weight and histological findings, in a dose-related manner. A high dose of Am-80 (3.0 mg/kg for 12 d) did not completely inhibit the disease, but delayed the symptoms and enhanced the delayed response. By prolonging the duration of treatment (18 d), Am-80 inhibited the onset of EAE during administration, but the symptoms of EAE appeared after the administration was stopped. Am-80 administerd for 12 d inhibited the DTH response on d 11 but not on d 22. RT-PCR studies demonstrated a strong expression of IFN-gamma, IL-6, IL-10, TGF-beta 1, TNF-alpha, and iNOS mRNA in spinal cord 13 d after immunization. However IFN-gamma, IL-10, TNF-alpha, and iNOS mRNA expression (on d 13) was suppressed by Am-80, except in the case of IL-6, hence the effect of Am-80 on the expression of IL-6 mRNA was examined in additional experiments. After Am-80 was administered for 12 d or 18 d, the expression of IL-6 mRNA was inhibited on d 12 or d 18, but increased on d 13 or d 19, respectively.

CONCLUSION

These findings suggest that inhibition of EAE by Am-80 is initiated by inhibition of IL-6 production.

摘要

目的

观察白细胞介素（IL）-6在实验性自身免疫性脑脊髓炎（EAE）发病过程中的作用。

方法

通过注射牛髓鞘碱性蛋白（MBP）免疫DA大鼠。采用逆转录聚合酶链反应（RT-PCR）检测细胞因子如IL-6、IL-10、肿瘤坏死因子-α（TNF-α）、转化生长因子-β1（TGF-β1）、干扰素-γ（IFN-γ）和诱导型一氧化氮合酶（iNOS）的mRNA。将MBP注射到耳部诱导迟发型皮肤超敏反应（DTH）。用苏木精-伊红（HE）染色对脊髓进行组织学研究。用脂多糖（LPS）加IFN-γ刺激培养的小鼠巨噬细胞克隆产生一氧化氮（NO）。

结果

DA大鼠发生EAE疾病，在第13天和第14天病情严重程度达到峰值。选择性IL-6抑制剂Am-80（1.0、3.0mg/kg）以剂量相关的方式抑制了临床评分、体重和组织学检查所观察到的病情恶化症状。高剂量Am-80（3.0mg/kg，共12天）并未完全抑制该疾病，但延迟了症状出现并增强了迟发型反应。通过延长治疗时间（18天），Am-80在给药期间抑制了EAE的发病，但在停药后EAE症状出现。给药12天的Am-80在第11天抑制了DTH反应，但在第22天未抑制。RT-PCR研究表明，免疫后13天脊髓中IFN-γ、IL-6、IL-10、TGF-β1、TNF-α和iNOS mRNA有强烈表达。然而，Am-80抑制了IFN-γ、IL-10、TNF-α和iNOS mRNA表达（在第13天），但IL-6除外，因此在额外实验中检测了Am-80对IL-6 mRNA表达的影响。在给予Am-80 12天或18天后，IL-6 mRNA表达在第12天或第18天受到抑制，但分别在第13天或第19天增加。