不同时长运动预处理对血管性痴呆大鼠学习记忆与血清铁死亡相关因子表达的影响

关键词：血管性痴呆  运动预处理  学习记忆能力  铁死亡

Keywords:vascular dementia  exercise preconditioning  learning and memory ability  ferroptosis

摘要：

      摘要 目的：观察不同时长运动预处理对血管性痴呆模型大鼠学习记忆与血清亚铁离子（Fe2+）、丙二醛（malondialdehyde，MDA）、谷胱甘肽（glutathione，GSH）铁死亡相关因子表达的影响。 方法：将60只SD雄性大鼠随机分为非运动预处理组和运动预处理组，非运动预处理组二次随机分为假手术组（S组）和模型组（M组），各10只；运动预处理组二次随机分为2周运动预处理假手术组（2WEP-S组）、2周运动预处理模型组（2WEP-M组）、4周运动预处理假手术组（4WEP-S组）及4周运动预处理模型组（4WEP-M组），各10只。2WEP-S组和2WEP-M组进行2周的游泳运动训练，4WEP-S和4WEP-M组进行4周的游泳运动训练，每周运动5天，每天30min。4周后，M组、2WEP-M组和4WEP-M组进行血管性痴呆（vascular dementia， VD）模型制备，S组、2WEP-S组和4WEP-S组进行模拟VD模型制备的假手术。Morris水迷宫评价大鼠空间学习记忆能力；尼氏染色法观察大鼠海马CA1区神经元形态和阳性表达情况；比色法检测大鼠血清Fe2+、MDA、GSH表达水平。 结果：与S组相比，M组大鼠平均逃避潜伏期显著延长，穿越平台次数减少（P＜0.01，P＜0.01），海马CA1区神经元排列疏松，胞质内尼氏小体明显减少，神经元受损严重，存活神经元细胞数量明显减少（P＜0.01），血清Fe2+、MDA表达升高，GSH表达减少（P＜0.01，P＜0.05）。与M组相比，2WEP-M组、4WEP-M组大鼠平均逃避潜伏期明显缩短（P＜0.01），海马CA1区神经元排列较整齐，细胞形态完整，胞质内尼氏小体相对较丰富，存活神经元细胞数量明显增多（P＜0.01），2WEP-M组、4WEP-M组大鼠血清Fe2+、MDA表达降低（P＜0.01，P＜0.05）、（P＜0.01，P＜0.05），GSH表达增加（P＜0.01，P＜0.01）。 结论：2周运动预处理和4周运动预处理均可改善血管性痴呆大鼠学习记忆能力，降低血管性痴呆大鼠血清中Fe2+、MDA水平，增加血清中GSH表达。

Abstract:

      Abstract Objective： To observe the effects of different duration exercise preconditioning on learning memory and the expression of serum ferrous ion （Fe2+）， malondialdehyde （MDA）， and glutathione （GSH） Ferroptosis-related factor in rats with vascular dementia. Method： Sixty SD male rats were randomly divided into non-exercise preconditioning group and exercise preconditioning group. The non-exercise preconditioning group was further randomized into a sham group （group S） and a model group （group M）， each with 10 rats； the exercise preconditioning group was further randomized into a 2-week exercise preconditioning sham group （group 2WEP-S）， a 2-week exercise preconditioning model group （group 2WEP-M）， a 4-week exercise preconditioning sham group （group 4WEP-S） and a 4-week exercise preconditioning model （group 4WEP-M）， each with 10 rats. All rats in the 2WEP-S and 2WEP-M groups underwent 2 weeks of swimming exercise training， and rats in 4WEP-S and 4WEP-M groups underwent 4 weeks of swimming exercise training， 5 days per week， 30 min per day. After 4 weeks， the M， 2WEP-M and 4WEP-M groups underwent vascular dementia （VD） model preparation, while the S， 2WEP-S and 4WEP-S groups underwent a sham operation simulating VD model preparation. The spatial learning and memory ability of the rats was evaluated using the Morris water maze. Neuron morphology and positive expression of neurons in the CA1 area of rat hippocampus was observed through Nissen staining. Fe2+， MDA and GSH contents in the rat serum tissues were quantified using the colorimetric assay. Result： Compared with group S， rats in group M had a significantly longer mean evasion latency and a reduced number of platform crossings（P<0.01， P<0.01）. Neurons in the hippocampal CA1 area were sparsely arranged, with a significant reduction in intracytoplasmic Nysted bodies， severe neuronal damage， and a significant reduction in the number of surviving neuronal cells （P<0.01）. The expression of serum Fe2+ and MDA were elevated， while the expression of serum GSH was reduced （P<0.01， P<0.05）. Compared with group M， the average evasion latency of rats in 2WEP-M and 4WEP-M groups was significantly shorter （P<0.01）. Neurons in CA1 area of the hippocampus were more neatly arranged， with intact cell morphology， relatively abundant intracytoplasmic Nystatin bodies， and a significantly increased number of surviving neuron cells（P<0.01）. The expression of serum Fe2+ and MDA in 2WEP-M and 4WEP-M groups was decreased （P<0.01， P<0.05），while the expression of serum GSH was increased （P<0.01， P<0.01）. Conclusion： Both 2-week and 4-week exercise preconditioning improved the learning memory ability， decreased serum levels of Fe2+ and MDA， and increased the serum expression of GSH in rats with vascular dementia.