Effectiveness of exercise interventions in animal models of multiple sclerosis

Multiple sclerosis (MS) is associated with an impaired immune system that severely affects the spinal cord and brain, and which is marked by progressive inflammatory demyelination. Patients with MS may benefit from exercise training as a suggested course of treatment. The most commonly used animal models of studies on MS are experimental autoimmune/allergic encephalomyelitis (EAE) models. The present review intends to concisely discuss the interventions using EAE models to understand the effectiveness of exercise as treatment for MS patients and thereby provide clear perspective for future research and MS management. For the present literature review, relevant published articles on EAE animal models that reported the impacts of exercise on MS, were extracted from various databases. Existing literature support the concept that an exercise regimen can reduce the severity of some of the clinical manifestations of EAE, including neurological signs, motor function, pain, and cognitive deficits. Further results demonstrate the mechanisms of EAE suppression with information relating to the immune system, demyelination, regeneration, and exercise in EAE. The role for neurotrophic factors has also been investigated. Analyzing the existing reports, this literature review infers that EAE is a suitable animal model that can help researchers develop further understanding and treatments for MS. Besides, findings from previous animal studies supports the contention that exercise assists in ameliorating MS progression

Regular Exercise Training Enhances Spatial Memory and Regulates Glucocorticoid System in Experimental Autoimmune Encephalomyelitis

Background & objective: Exercise has been shown to improve cognitive function in patients with multiple sclerosis (MS). Experimentally, glucocorticoids (GCs) treatment has been observed to improve cognitive deterioration in an autoimmune model for MS, experimental autoimmune encephalomyelitis (EAE). We aimed to determine the combined effect of exercise and 4 mg/kg of dexamethasone (Dex) for 4 weeks on spatial memory in EAE. Materials & Methods: Rats with EAE were subjected to the Morris water maze (MWM) for four days and a prop test for one day. The prop test was repeated on day 40 post-induction (dpi). Rats were randomly assigned to one of four groups (10 rats per group): control EAE without treatment; EAE + dexamethasone, (EAE + Dex); EAE + exercise (EAE + Ex); and EAE+Dex+Ex. Rats receiving dexamethasone were administered 4 mg/kg injections daily for two weeks after EAE induction. Exercise training was initiated on a motorized treadmill 2 weeks before EAE induction and continued until 14 dpi. On day 41, animals were dissected and CORT level was assessed by enzyme-linked immunosorbent assay corticosterone kit. Results: One-way analysis of variance (ANOVA) with repeated measures followed by a protected LSD post hoc test indicated that, EAE+Ex group increased body weight (P 0.001) and swimming speed (p>0.002). Conclusion: The protocol selected in this study was an effective treatment for the EAE model to improve spatial memory and regulate corticosterone concentrations