The effect of home-based exercise on the thalamic pathology and metabolites concentration in people with multiple sclerosis: Evidence from magnetic resonance imaging, spectroscopy and diffusion

To enhance knowledge about the role of regular physical activity on brain structure and function in multiple sclerosis, this study designed to investigate the effect of 6-month home-based exercise on the thalamic pathology and metabolites concentration using magnetic resonance imaging, diffusion and spectroscopy techniques. In this study, 56 people with multiple sclerosis (39 female and 13 male, age: 37.33±9.59 year) were randomly divided into two groups, home-based exercise and control. Intervention include aerobic (3-session per week, 50-75 % heart rate reserve) and resistance (2-session per week, rating of perceived exertion 5-8) exercise. Brain and thalamic volume using magnetic resonance imaging, thalamic metabolites using spectroscopy, and microstructure changes using diffusion technique were assessed before and after the intervention. Results showed that six months of home-based exercise did not have a significant effect on brain, thalamic volume and diffusion parameters including fractional anisotropy, mean penetration, axial penetration and radial penetration (p>0.05). Thalamic metabolites analysis showed that home-based exercise resulted in a significant increase in the ratio of N-acetylaspartate and N-acetylaspartylglutamate to creatine (p<0.007) and a significant decrease in the ratio of choline to creatine and inositol to creatine (p<0.22 and p<0.002, respectively). Overall, the results provided evidence about the beneficial effects of regular physical activity on thalamic metabolites associated with myelin loss and axonal function in the brain of people with MS using spectroscopy imaging. However, home-based exercise was not associated with change in diffusion parameters as indicators of changes in thalamic microstructures, which may indicate that longer-term intervention is needed.