Voluntary wheel running is widely used as a physical activity (PA) model in rodents, but most studies investigate the beneficial effects of this intervention in socially isolated mice. Social isolation stress (SIS) is associated with vulnerability to oxidative stress and reduced mitochondrial activity. Thus, the aim of this study was to investigate the effects of free access to a running wheel for 21 days on the various markers of the cellular redox/antioxidant status as well as mitochondrial function of mice subjected to SIS or maintained in groups of 3 in the homecage. SIS increased thiobarbituric acid reactive substance (TBARS) levels in the cerebral cortex, and PA intervention was not able to reverse such alteration. PA reduced TBARS levels in the liver of grouped mice and gastrocnemius of socially isolated mice. PA increased nonprotein thiol (NPSH) levels in the cerebral cortex of grouped mice. Furthermore, socially isolated mice presented lower glutathione peroxidase (GPx) activity in the cerebellum and gastrocnemius, and glutathione reductase (GR) activity in the cerebral cortex and liver. By contrast, SIS induced higher GPx activity in the cerebral cortex and heart. PA reduced GPx (cerebral cortex) and GR (cerebral cortex and liver) activities of socially isolated mice. SIS caused higher activity of mitochondrial complexes I and II in the cerebral cortex, and the PA paradigm was not able to alter this effect. Interestingly, the PA produced antidepressant-like effect at both SIS and control groups. In conclusion, the results showed the influence of SIS for the effects of PA on the antioxidant status, but not on the mitochondrial function and emotionality.

自愿轮跑被广泛用作啮齿动物的身体活动 (PA) 模型，但大多数研究调查了这种干预对社会孤立小鼠的有益影响。社会隔离压力 (SIS) 与易受氧化应激和线粒体活性降低有关。因此，本研究的目的是研究自由使用跑轮 21 天对细胞氧化还原/抗氧化状态的各种标志物以及接受 SIS 或以 3 只一组维持的小鼠的线粒体功能的影响家笼。SIS 增加了大脑皮层中的硫代巴比妥酸反应物质 (TBARS) 水平，而 PA 干预无法逆转这种改变。PA 降低了分组小鼠肝脏和社会隔离小鼠腓肠肌中的 TBARS 水平。PA 增加了分组小鼠大脑皮层中的非蛋白硫醇 (NPSH) 水平。此外，社会隔离小鼠在小脑和腓肠肌中表现出较低的谷胱甘肽过氧化物酶 (GPx) 活性，在大脑皮层和肝脏中表现出较低的谷胱甘肽还原酶 (GR) 活性。相比之下，SIS 在大脑皮层和心脏中诱导了更高的 GPx 活性。PA 降低了社交隔离小鼠的 GPx（大脑皮层）和 GR（大脑皮层和肝脏）活动。SIS 导致大脑皮层中线粒体复合物 I 和 II 的活性更高，PA 范式无法改变这种效果。有趣的是，PA 在 SIS 和对照组中都产生了抗抑郁样作用。总之，结果表明 SIS 对 PA 抗氧化状态的影响，