The impact of voluntary swimming activity on the content of some proteins related to the myelination of hippocampus tissue in multiple sclerosis model rats

Background and Purpose: Multiple sclerosis (MS) is a chronic inflammatory, autoimmune, and multi-factorial disease that substantially reduces patients’ quality of life. Since physical activity may offer anti-inflammatory and axonal protection benefits to these patients, this study aims to explore the impact of swimming physical activity on the content of particular proteins critical for the myelination of hippocampal tissue in cuprizone-induced rat’s model of MS.
Materials and Methods: In the current investigation, a cohort of 20 male Wistar rats with an average age of 12 weeks and the weight is 230 grams purchased and was divided into four groups: healthy control, MS control, healthy training, and MS training. The MS disease model was induced by administering food containing 0.5% cuprizone throughout the entire 12-week research protocol. Upon confirming MS induction through the rotarod test, rats underwent a six-week voluntary swimming protocol. In this way, in the first week, they did 10 minutes of voluntary swimming activity without applying loads, and in order to apply overload, the duration of voluntary swimming was added every week by 5 minutes. In order to maintain the adaptations achieved in the activity, the duration of the swimming activity in the fifth and sixth weeks was considered constant and 30 minutes. After the end of the training protocol, Memory and balance were assessed via shuttle box and rotarod tests. Subsequently, the hippocampal tissue was extracted, and PLP and MBP protein levels were measured using western blot and the amount of NGF protein was measured using the ELISA method. The data were analyzed by one-way ANOVA test and then Tukey's post hoc test at a significance level of less than 0.05.
Results: The findings of the shuttle box and rotarod experiments revealed that the MS group had impaired memory function and balance maintenance, but these improved significantly after a period of swimming activity (p<0.001). Also, no significant difference was observed in the results of the shuttle box and rotarod tests in the healthy training and healthy control groups (p>0.05). The results of the present study showed that the content of NGF, PLP and MBP proteins in the patient control group significantly decreased compared to the healthy control group (p<0.05), Also, the results showed that the amounts of these proteins increased significantly in the MS training group compared to the MS control group (p<0.05). The results showed that there is a significant difference in the content of NGF and PLP proteins between healthy training group and healthy control group (p<0.05). While there is no significant difference in MBP protein content between the healthy training and healthy control groups (p>0.05).
Conclusion: Based on the current research findings, it can be assumed that swimming exercise activity has notable anti-inflammatory and neuroprotective effects by creating molecular adaptations, and it can probably be considered as a safe, non-pharmacological and complication-free method to improve the symptoms of MS sufferers.