芬戈莫德对卒中后抑郁大鼠的治疗作用

The therapeutic effect of fingolimod on rats with post-stroke depression

目的:观察芬戈莫德(FTY720)对卒中后抑郁(PSD)大鼠的治疗效果并初步探索其作用机制。方法:50只SD大鼠依照随机对照方法分为5组,分别为假手术组(sham)、卒中组(MCAO)、卒中后抑郁组(PSD)、氟西汀治疗组(PSD^+FLU)以及芬戈莫德治疗组(PSD^+FTY)。采取大脑中动脉线栓法建立局灶性脑缺血模型,联合慢性不可预见的温和性应激(CUMS)及孤养法建立PSD模型。记录大鼠每周体重,运用敞箱实验和糖水偏好实验评估大鼠的行为学表现;HE染色观察大鼠海马组织形态;ELISA检测大鼠血清中IL-1β、IL-6和TNF-α的含量;Western Blot检测大鼠海马组织中IL-1β、IL-6和TNF-α的表达水平;流式细胞术检测大鼠外周血T细胞亚群水平。结果:与sham组和MCAO组相比,PSD组大鼠体重、敞箱实验得分及糖水偏好比例显著减低(P <0.05),HE染色显示海马组织CA1和CA3区呈现细胞萎缩和数量减少等现象,大鼠血清及海马组织中IL-1β、IL-6和TNF-α的表达水平均显著增高(P <0.05),大鼠外周血CD3^+T细胞和CD3^+CD4^+T细胞的数量升高(P<0.05);与PSD组相比,PSD^+FTY组大鼠体重、敞箱实验得分及糖水偏好比例显著升高(P <0.05);HE染色显示海马组织CA1和CA3区细胞损伤现象减少;大鼠血清及海马组织中IL-1β、IL-6和TNF-α的表达水平均显著降低(P <0.05);大鼠外周血CD3^+、CD3^+CD4^+和CD3^+CD8^+T细胞的数量均显著减低(P <0.05)。结论:FTY720能够有效改善海马组织损伤进而缓解PSD大鼠的抑郁行为,其机制可能是降低外周血T细胞数量从而进一步降低了血清及海马组织中IL-1β、IL-6与TNF-α水平。

Objective: To investigate the therapeutic effect and possible mechanism of fingolimod(FTY720) on rats with post-stroke depression(PSD).Methods: 50 SD rats were randomly divided into 5 groups,including sham-operation(sham),middle cerebral artery occlusion(MCAO),PSD,treatment of fluoxetine(PSD ^+ FLU),and treatment of fingolimod(PSD ^+ FTY) group with 10 rats in each.After the establishment of focal cerebral ischemia model by MCAO,models of post-stroke depression were developed by the method of combining the chronic unpredictable mild stress(CUMS) and isolation for 21 days.The weight of each rat was recorded every week.Depression behavior was assessed by sucrose preference test and open field test.The pathological changes in the hippocampus were observed by HE staining.The expression of IL-1β,IL-6,and TNF-α in serum were detected by ELISA.The expression of IL-1β,IL-6,and TNF-α in hippocampus were detected by Western Blot.The number of T cell subsets in blood were detected by flow cytometry.Results: Compared with the sham group and MCAO group,the PSD group had significantly lower weight,open-field test score and sucrose preference ratio(P < 0.05).HE staining showed atrophy and degeneration of neurons in CA1 and CA3 areas of hippocampus.The expression of IL-1β,IL-6,and TNF-α in serum and hippocampus increased significantly(P < 0.05).The number of CD3 Tcells ^+ and CD3^+CD4^+T cells in blood of rats were also increased(P < 0.05).Compared with the PSD group,the weight,open-field test score and sucrose preference ratio of the fingolimod treatment group increased significantly(P < 0.05).HE staining showed that the degeneration of neurons in CA1 and CA3 areas of hippocampus decreased.The expression of IL-1β,IL-6,TNF-α in serum and hippocampus decreased significantly(P < 0.05).The number of CD3^+T cells,CD3^+CD4^+T cells and CD3^+CD8^+T cells in the blood of rats were significantly decreased(P < 0.05).Conclusions: Fingolimod can reduce the damage of hippocampal neurons and rescue the depression behavior of post-stroke depression rats.Its mechanism could be lowering the levels of IL-1β,IL-6,and TNF-α in serum and hippocampus by reducing the number of T cells in blood.