热休克预处理对实验性自身免疫性脑脊髓炎大鼠模型的保护作用

Protective effects of heat shock preconditioning on the experimental autoimmune encephalomyelitis rats

摘要:

目的：观察热休克预处理对实验性自身免疫性脑脊髓炎（EAE）热休克蛋白70(HSP70)表达及神经细胞凋亡的影响，探讨其对EAE模型的保护作用。方法：将36 只Wistar大鼠随机分为对照组(CON), EAE组和热休克预处理组 (HSP)。EAE组，采用Wistar大鼠制作EAE模型；HSP组给予热休克预处理；CON组不行特殊处理。观察临床症状，进行神经功能评分。于免疫后14～17 d处死动物，取脊髓行苏木精-伊红染色，HSP70免疫组化及神经细胞的凋亡的检测。结果：HSP能明显改善EAE临床症状，降低临床评分，延缓发病（P<0.05）, 增加脊髓HSP70阳性细胞表达（21.08±0.87 vs 10.17±0.51, P<0.01），抑制神经细胞凋亡（21.92±1.00）% vs （58.92±1.67）%， P<0.01。结论： 热休克预处理对EAE大鼠具有一定的神经保护作用, 其保护机制可能与增加HSP70表达而导致神经细胞凋亡减少有关。［中国当代儿科杂志，2007，9（6）：563-566］

Abstract:

OBJECTIVE: To study the effects of heat shock preconditioning on the expression of heat shock protein-70 (HSP70) and apoptosis of the neuron in experimental autoimmune encephalomyelitis (EAE) rats. METHODS: Thirty-six Wistar rats were randomly divided into control, EAE and heat shock preconditioning groups (n=12 each). The EAE animal model was induced with guinea pig myelin basic protein. Heat shock preconditioning was performed 24 hrs prior to the EAE model inducement. No treatment was done in the control group. The neurological signs were observed after immunization. The spinal cords were removed and stained with hematoxylin and eosin. HSP70 was detected by immunohistochemistry. Apoptosis of the neuron was measured by TUNEL. RESULTS: Heat shock preconditioning significantly alleviated clinical signs and neuronal injury. HSP70 expression in the heat shock preconditioning group was significantly higher than in the untreated EAE group (21.08±0.87 vs 10.17±0.51; P<0.01). Heat shock preconditioning suppressed apoptosis of the neuron compared with the EAE group (apoptosis rate: 21.92±1.00% vs 58.92±1.67%; P<0.01). CONCLUSIONS: Heat shock preconditioning might improve the neurological outcome in EAE rats, possibly through the induction of HSP70 synthesis and the reduction of apoptosis of the neuron in spinal cords.［Chin J Contemp Pediatr, 2007, 9 (6):563-566］