Effect of GFAP and MMP9 expressions on tight junction proteins in experimental autoimmune encephalomyelitis rats
10.3760/cma.j.issn.1671-8925.2018.08.003
- VernacularTitle:实验性自身免疫性脑脊髓炎大鼠紧密连接蛋白表达的变化研究
- Author:
Xiuli GUO
1
;
Chuanbao WANG
;
Lei GUO
Author Information
1. 烟台山医院神经内科
- Keywords:
Multiple sclerosis;
Experimental autoimmune encephalomyelitis;
Blood-brain barrier;
Tight junction;
Astrocyte;
Matrix metalloproteinase-9
- From:
Chinese Journal of Neuromedicine
2018;17(8):772-777
- CountryChina
- Language:Chinese
-
Abstract:
Objective To observe the expressions of tight junctional proteins in rats with experimental autoimmune encephalomyelitis (EAE),and to explore their relevant pathological mechanism.Methods Twenty-four Sprague Dawley rats were selected and randomly divided into a control group and a EAE group,and rats in the EAE group were subcutaneously injected at the footpad with autoimmune antigens to induce EAE models.The clinical behavioral scale scores of the rats 12 d after immunization were observed and recorded daily.The rats were sacrificed 23 d after immunization,and the histopathological changes of the brain tissues were observed by hematoxylin-eosin (HE) staining and fast blue (LFB) staining;the expressions of tight junction proteins Occludin,ZO-1 and Claudin-5 in the brain tissues were evaluated by immunofluorescence staining;the mRNA and protein levels of glial fibrillary acidic protein (GFAP,surface marker of astrocytes) and matrix metalloproteinase-9 (MMP9) in brain tissues were detected by reverse transiption-PCR (RT-PCR) and Western blotting,respectively.Results As compared with those in the control group,the clinical behavioral scale scores from 15 to 23 d of immunization and histopathological scale scores in the EAE group were significantly increased (P＜0.05).In EAE group,a lot of inflammatory cell infiltration and myelin loss in the cerebellar white matter were noted.As compared with those in the control group,the expressions of Occludin,ZO-1,and Claudin-5 in EAE group were significantly decreased (P＜0.05),and the mRNA and protein expressions of GFAP and MMP9 were significantly up-regulated (P＜0.05).Conclusion The activation of astrocytes and increased expression of MMP9 may reduce expressions of Occludin,ZO-1 and Claudin-5,disrupt blood-brain barrier,promote inflammatory cell infiltration,and increase myelin loss during EAE.
