Fanaei Hamed, Shoorijeh Behrad Tabatabaei, Hafezinouri Hamid, Mirzaei Ilia, Parsi-Moud Abolfazl
Pregnancy Health Research Center, Department of Physiology, Zahedan University of Medical Sciences, Zahedan, Iran.
School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran.
Exp Gerontol. 2024 Jul;192:112453. doi: 10.1016/j.exger.2024.112453. Epub 2024 May 14.
Social isolation (SI) after stroke reduces recovery. The aim of this study was to evaluate the effects of SI on corticosterone release and recovery after stroke in aged rats. A total of 64 male Wistar rats (aged 24 months) were used in the present study. All rats were housed in pairs for two weeks. After two weeks, rats were randomly assigned to one of four groups: (1) rats underwent sham surgery and kept socially isolated (control/social isolated (CO/SI) group); (2) rats underwent sham surgery and kept pair housed (control/pair housed (CO/PH) group); (3) rats underwent middle cerebral artery occlusion (MCAO) surgery and kept socially isolated (stroke/isolated (ST/SI) group); (4) rats underwent MCAO surgery and kept pair housed (stroke/pair housed (ST/PH)) group. Behaviors were assessed using the adhesive removal test, rotarod test and social interaction test at 1st, 7th, 14th and 21st days after stroke. Serum biochemical analysis was also performed on the behavioral testing days. Results showed THAT serum corticosterone and MDA levels in CO/PH group were significantly lower than CO/SI group. Serum BDNF levels in CO/PH group was significantly higher than CO/SI group. Serum corticosterone and MDA levels in ST/PH group were lower than ST/SI group. In ST/PH group, serum Total antioxidant capacity (TAC) and BDNF levels were significantly higher than ST/SI group. Biochemical analysis of certain regions of the brain (hippocampus, striatum and cerebral cortex) was performed on 21st day after stroke. In the hippocampus of CO/PH group, BDNF and TAC levels were significantly higher than CO/SI group. The hippocampal MDA level of CO/PH group were significantly lower than CO/SI group. BDNF and TAC levels in the hippocampus, striatum and cerebral cortex of ST/PH group were significantly higher and MDA level was significantly lower as compared with ST/SI group. Both ischemic groups showed sensorimotor recovery over a 21-day period, but recovery of ST/PH group was significantly greater than ST/SI group. Total social interaction time in ST/PH group was significantly longer than ST/SI group. Based on the results of this study, social interaction after stroke enhances histologic and sensorimotor recovery through reduction of HPA activity and corticosterone release, leading to increased TAC and BDNF levels.
中风后的社会隔离（SI）会降低恢复能力。本研究的目的是评估SI对老年大鼠中风后皮质酮释放和恢复的影响。本研究共使用了64只雄性Wistar大鼠（24个月龄）。所有大鼠成对饲养两周。两周后，将大鼠随机分为四组之一：（1）大鼠接受假手术并保持社会隔离（对照组/社会隔离（CO/SI）组）；（2）大鼠接受假手术并成对饲养（对照组/成对饲养（CO/PH）组）；（3）大鼠接受大脑中动脉闭塞（MCAO）手术并保持社会隔离（中风/隔离（ST/SI）组）；（4）大鼠接受MCAO手术并成对饲养（中风/成对饲养（ST/PH）组）。在中风后的第1、7、14和21天，使用粘胶去除试验、转棒试验和社会互动试验评估行为。在行为测试日也进行了血清生化分析。结果显示，CO/PH组的血清皮质酮和丙二醛（MDA）水平显著低于CO/SI组。CO/PH组的血清脑源性神经营养因子（BDNF）水平显著高于CO/SI组。ST/PH组的血清皮质酮和MDA水平低于ST/SI组。在ST/PH组中，血清总抗氧化能力（TAC）和BDNF水平显著高于ST/SI组。在中风后第21天对大脑的某些区域（海马体、纹状体和大脑皮层）进行了生化分析。在CO/PH组的海马体中，BDNF和TAC水平显著高于CO/SI组。CO/PH组的海马体MDA水平显著低于CO/SI组。与ST/SI组相比，ST/PH组海马体、纹状体和大脑皮层中的BDNF和TAC水平显著更高，MDA水平显著更低。两个缺血组在21天内均显示出感觉运动功能的恢复，但ST/PH组的恢复明显大于ST/SI组。ST/PH组的总社会互动时间显著长于ST/SI组。基于本研究结果，中风后的社会互动通过降低下丘脑-垂体-肾上腺（HPA）活性和皮质酮释放来增强组织学和感觉运动功能的恢复，从而导致TAC和BDNF水平升高。
