Proceedings of The Physiological Society

Europhysiology 2018 (London, UK) (2018) Proc Physiol Soc 41, PCB147

Poster Communications

Effects of High Intensity Interval versus Continuous Moderate Intensity Training on Post Traumatic Stress Disorder Induced Cognitive Impairment in Rats

T. Koyuncuoğlu1, Z. Meral2, N. Çetrez2, B. Gönenç2, H. Sevim2, E. Kuntsal Dertsiz3, D. Akakin3, M. Yüksel4, Ö. Kasimay Çakir1

1. Department of Physiology, Marmara University, School of Medicine, Istanbul, Turkey. 2. 3rd Grade Medical Student at School of Medicine, Marmara University, Istanbul, Turkey. 3. Department of Histology and Embryology, Marmara University, Istanbul, Turkey. 4. Vocational School of Health Services, Marmara University, Istanbul, Turkey.

High intensity interval training (HIIT) has become popular recently1. Post-traumatic stress disorder (PTSD) declines cognitive capacity. This study aimed to compare the effect of HIIT and continuous moderate-intensity training (CMT) on cognitive functions and anxiety levels of PTSD induced rats and to investigate possible underlying oxidative and anti-oxidative mechanisms. Female Wistar Albino rats (n=44) were randomly divided into six groups: Sedantery (SED), CMT, HIIT groups and PTSD-induced SED, CMT, and HIIT groups (n=6-8). Exercise groups performed treadmill training for 6 weeks (5 days/week, 30 min/day). Following a 2 min warm-up period, HIIT groups exercised 4 min at 80-90% of maximum oxygen consumption (VO2max) and 3 min at 50-60% VO2max for 4 cycles and CMT groups exercised at 50-60% VO2max. On the fifth week of exercise sessions, a single prolonged stress protocol was used to induce PTSD. Following the last stress stimulation, cognitive functions were evaluated by object recognition test. Anxiety-like behavior was analyzed via Hole-board and elevated plus maze tests. The passive avoidance test was performed to evaluate fear conditioning. After the rats were decapitated, malondialdehyde (MDA) levels, glutathione (GSH) content, myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) activities, luminol and lucigenin levels were measured, and histopathological damage was evaluated. The data was analyzed by one-way ANOVA and student's t test. As an indicator of anxiety-like behavior, decreased proportion of time spent on the open arms, declined head-dipping frequency and rearing number in SED+PTSD group were increased in CMT+PTSD and HIIT+PTSD and the significant increase in freezing time was decreased only in HIIT+PTSD group (p<0.05-0.001). PTSD-related cognitive decline in SED+PTSD group was increased in CMT+PTSD and HIIT+PTSD groups (p<0.05-0.01). The luminol and lucigenin levels, MPO activity and histological damage were increased in SED+PTSD group, while the scores were depressed in CMT+PTSD and HIIT+PTSD groups (p<0.05-0.001). The increased brain MDA levels in SED+PTSD group were suppressed in HIIT+PTSD group (p<0.01-0.001). The decreased antioxidant GSH levels and CAT activity were significantly increased in CMT+PTSD and HIIT+PTSD groups, respectively (p<0.05-0.001). Compared to SED group, the latency as a sign of fear conditioning decreased in SED+PTSD (p<0.05). Microscopically, neuronal damage observed in the cortex and hippocampus of PTSD-SED rats was alleviated in both exercise groups. These findings demonstrate that impaired cognitive function in PTSD was improved by both of the exercise protocols but mainly by HIIT via decreasing oxidative stress, anxiety levels and neuronal damage.

Where applicable, experiments conform with Society ethical requirements