Treadmill exercise ameliorates memory deficits and hippocampal inflammation in ovalbumin-sensitized juvenile rats

Abstract

The behavioral changes, including spatial learning and memory impairment as well as depressive- and anxiety-like behaviors in an animal model of asthma were demonstrated previously. On the other hand, there is increasing evidence that the anti-inflammatory actions of exercise are related to their neuroprotective properties against different insults in the brain. This study was aimed to explore the effects of moderate treadmill exercise on cognitive deficits and possible anti-inflammatory mechanisms in ovalbumin (OVA)-sensitized rats. The exercise groups were trained to run on the treadmill 30 min/day with an intensity of 12 m/min, 5 days/week for 4 weeks. Animals in the OVA groups were sensitized by two intraperitoneal (i.p.) injections of OVA (10 μg/injection) and challenged with OVA by inhalation during the treadmill running exercise period. Passive avoidance (PA) memory, levels of interleukin (IL)-10 and tumor necrosis factor (TNF)-α in the hippocampus, total and differential white blood cell (WBC) count in the blood as well as pathological changes of the lung were then evaluated. OVA-sensitization was resulted in cognitive deficits in the PA task, along with increased total and differential WBC in blood and TNF-α in the hippocampus. However, exercise ameliorated these changes and increased the IL-10 level in the hippocampus, suggesting that moderate treadmill exercise can improve memory impairment in OVA-sensitized rats due to its anti-inflammatory properties.