实验性自身免疫性脑脊髓炎小鼠神经损害与脑组织中丝裂原活化蛋白激酶表达的关系

目的观察实验性自身免疫性脑脊髓炎(EAE)模型小鼠脑组织中丝裂原活化蛋白激酶(MAPKs)表达变化及其与神经损害的关系。方法 C57BL/6小鼠随机分为:EAE组(n=12),采用髓鞘少突胶质细胞糖蛋白35-55多肽(MOG35-55)制备成抗原乳剂免疫小鼠;对照组(n=10),用生理盐水处理小鼠。每日观察两组小鼠的行为学变化,并进行神经功能障碍评分。于高峰期处死小鼠,冰冻处理脑与脊髓,行苏木精-伊红染色观察脊髓组织的炎症细胞浸润,LFB染色观察脊髓组织的髓鞘脱失,蛋白印迹法检测小鼠脑组织中MAPKs表达。分析EAE小鼠神经功能障碍改变与中枢神经组织MAPKs表达量的相关性。结果 EAE组与对照组比较:日均神经行为学评分增加(P0.01);脊髓炎症细胞浸润增多(P0.001),髓鞘脱失增多(P0.001)。P-ERK(42)、P-ERK(44)、P-JNK(54)表达量均增多(P0.01、P0.05、P0.05)。神经功能障碍与P-ERK(42)、P-ERK(44)、P-JNK(54)表达呈正相关。结论 EAE高峰期神经损伤程度与中枢神经组织中的P-ERK(42)、P-ERK(44)、P-JNK(54)表达增加相平行,提示MOG35-55诱导的EAE中枢神经损伤可能与MAPKs所激活的信号通路有关。

Correlations between Neurological Damage of Experimental Autoimmune Encephalomyelitis Mouse and Changes of Mitogen-activated Protein Kinases

Aim To investigate the changes ofmitogen-activated protein kinases （MAPKs） in experimental autoimmune encephalomyelitis （EAE） mouse brain and to further investigate the correlation between their changes and the neurological damages. Methods C57BL/6 mice were randomly chosen into two groups： EAE group （n=12）, which were induced into EAE by immunized with the myelin oligodendrocyte glycoprotein 35- 55 （MOG35.ss） peptides and incomplete Freund＇ s adjuvant; Control group （n=10） in which mice were treatedwith saline instead of MOG35-55. The mice were observed and their neurological deficiencies were recorded everyday. They were executed at the peak stage. With hematoxylin eosin staining （HE staining） and LFB staining, the inflammatory cells infiltration and the demyelination in the spinal cord were investigated. By using the Western blot, the changes of P-p38 MAPK, P-ERK, P-JNK and p-38 MAPK, ERK, JNK in the brain were observed. Then correlation between the neurological damages and the expression of MAPKs in the central nervous tissues were analysed. Results Compared with the control group, the results of the EAE group was as follows： mean daily scores raised （P〈0.01）; The infiltration of inflammatory cells into spinal cords increased （P〈0.001）; The demyelination in EAE mice spinal cord was much more severe （P〈0.001）; The expression of P-ERK（42）（P〈0.01）, P-ERK（44）（P〈0.05）, P-JNK（54）（P〈0.05） obviously increased, while the changes of other proteins were not significantly different between the EAE group and the control group; Neurological damage of each EAE mouse had positive correlationship with the expression of P-ERK（42）, P-ERK（44） and P-JNK（54）. Conclusion The severity of neurological damages during MOG33.55-induced EAE had positive correlationship with the expression level ofP-ERK（42）, P-ERK（44） and P-JNK（54）, which suggested that activation of P-ERK（42）, P-ERK（44） and P-JNK（54） signal pathway may be involved in the neurological damage during EAE development.