سمانه راهدار

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 aimed to explore the impact of swimming training on the proteins critical for the myelination of hippocampal tissue in cuprizone-induced rat’s model of MS.

In the current investigation, 20 male Wistar rats with an average age of 12 weeks and the weight of 230 g were purchased and divided randomly 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 for 12 weeks. Upon confirming MS induction through the rotarod test, rats underwent a six-week swimming protocol. In the first week, they performed 10 min swimming without applying loads, and thereafter the duration of swimming was added by 5 min every week. In order to maintain the adaptations the duration of the swimming for the fifth and sixth weeks was constant and was kept at 30 min. At the end of the training protocol, memory and balance were assessed via shuttle box and rotarod tests. Subsequently, the hippocampal tissue was extracted, and analyzed for determining the proteolipid protein (PLP) and Myelin basic protein (MBP) protein levels by using western blot and the amount of Nerve growth factor (NGF) protein was measured by using the ELISA method. The data were analyzed using one-way ANOVA and post-hoc comparisons were made by using Tukey's test at a significance level of p<0.05.

The findings of the shuttle box and rotarod tests revealed that the MS group had impaired memory function and balance maintenance, but these improved significantly after swimming training (p<0.001). No significant difference was observed in the results of the shuttle box and rotarod tests between healthy training and healthy control groups (p>0.05). The results of the present study showed that NGF, PLP and MBP proteins in the patient control group were significantly lower compared to the healthy control group (p<0.05). Furthermore, data analyses 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 was a significant difference for NGF and PLP proteins between healthy training group and healthy control group (p<0.05), whereas, no significant differences in MBP protein levels were found between the healthy training and healthy control groups (p>0.05).

Based on the current research findings, it can be concluded that swimming exercise has notable anti-inflammatory and neuroprotective effects through favourable molecular adaptations, and it can probably be considered as a safe, non-pharmacological and complication-free method to improve the symptoms in MS patients.

One of the chronic inflammatory diseases of the central nervous system is multiple sclerosis (MS). Betaine has anti-inflammatory and neuroprotective effects. The present study was conducted with the aim of investigating the effect of betaine on tissue changes of the cerebellum and motor activity in the experimental model of MS.

In this experimental research, 20 adult male rats (12-week-old) were divided into control, Ms, Ms+ betaine and betaine. To create the MS model, animals were fed food containing 0.5% cuprizone for 12 weeks. For treatment, betaine was given at a dose of 1% in drinking water for the last 6 weeks. At the end of period, in order to measure balance and motor coordination, rotarod, open field, and inverted grid tests were performed, and the cerebellum of the animals was studied in terms of histological alterations.

Motor activities and maintaining balance in the MS group showed a significant decrease compared to control group, while treatment with betaine improved these symptoms. In the histological studies, tissue changes in Purkinje cells, such as a decrease in the number, condensation and pyknosis of the nucleus, a decrease in the diameter of the cell body and the nucleus of these cells were seen in the MS group. While the MS group receiving betaine, the changes were clearly improved and the Purkinje cells were able to maintain their number and shape.

The betaine can be considered as an effective biomolecule in the process of nerve regeneration and improvement of motor behaviors in patients with MS.

Diabetes can causes disturbances in glucose homeostasis and negative changes in the heart muscle. Since physical activity in people with diabetes may affect the heart tissue, the aim of this study was to investigate the effect of high intensity interval training (HIIT) on content of FOXO3, PI3K and AKT proteins in the heart tissue of Wistar rats with type two diabetes.

In the present study, 36 male Wistar rats were divided into four groups: diabetes - control, diabetes - exercise, control – healthy, and exercise - healthy. After two months of high-fat diet and induction of diabetes by Streptozotocin (35 mg/kg) in diabetes-control and diabetes-exercise groups, the animals in diabetes-exercise and exercise-healthy groups performed the HIIT protocol based on a percentage of Vmax achieved, that it was with two-minutes intervals and increasing number of intervals for eight weeks and five sessions per week. 48 hours after the last training session, cardiac tissue was extracted and the content of FOXO3, PI3K and AKT proteins were assessed using Western blotting. In addition, a histological study was performed at the tissue level using hematoxylin and Eosin staining. To analyze the data one-way analysis of variance and Tukey tests were used at a significance level of p<0.05.

The content of FOXO3 protein in diabetic groups significantly increased compared to healthy groups (p=0.001). In addition, the content of PI3K and AKT proteins in diabetes-control group also significantly decreased compared to healthy groups (p=0.001 and p=0.009, respectively), while the content of these two proteins significantly increased after training (p=0.01 and p=0.001, respectively). Moreover, at the tissue level of heart, the thickness and length of cardiac myocytes significantly increased due to diabetes (p=0.001); while after HIIT, this pathological hypertrophy reduced (p=0.02 and p=0.01, respectively).

Finally, it can be stated that although the use of this training method did not show a change in the amount of FOXO3 protein, but it was able to increase the amount of PI3K and AKT proteins and improve the pathological hypertrophy caused by diabetes.