Physical exercise may help reduce inflammation in MS, study suggests
Findings in mice and a small patient study point to immune, vagus nerve effects
Written by |
A man takes part in physical therapy exercises with the assistance of his therapist. (Image from iStock)
- Physical exercise may help reduce inflammation in multiple sclerosis.
- It shifts immune T-cell activity, partly through the vagus nerve.
- Exercise shows promise as a potential approach to support MS treatment.
Physical exercise may help reduce inflammation in multiple sclerosis (MS) by changing the activity of immune T-cells, a new study reports.
Findings suggest this effect may depend in part on signaling through the vagus nerve, which connects the brain to other organs and helps regulate automatic bodily functions.
Study explores how exercise may affect immune activity in MS
“These findings highlight the therapeutic potential and disease-modifying value of [physical exercise] in MS and suggest the vagal pathway as a key modulator of exercise-induced neuroimmune benefits,” the researchers wrote in the study, “Physical exercise modulates T cell activity and mitigates synaptic dysfunction in multiple sclerosis through vagus nerve engagement,” published in Brain, Behavior, and Immunity.
MS is a chronic disease marked by inflammation that damages the brain and spinal cord. Consistent evidence suggests that regular exercise can benefit people with MS. However, the biological mechanisms behind these effects are not fully understood.
To explore this, scientists in Italy conducted experiments in mice with experimental autoimmune encephalomyelitis (EAE), a lab-induced condition commonly used as a model of MS. Some mice exercised regularly on a running wheel, while others did not.
In line with prior evidence, mice that exercised had less severe disease and showed less synaptic dysfunction, referring to problems in the connections where nerve cells communicate with each other.
Exercise also changed the mice’s immune cells, particularly T-cells, which help regulate inflammation. Mice in the exercise group had lower levels of pro-inflammatory T-cells and higher levels of regulatory T-cells, which help suppress excessive inflammation.
Exercise linked to reduced inflammatory T-cell activity in mice
Overall, these findings suggest exercise may shift the immune system toward a less inflammatory state in mice. This was accompanied by changes in how these immune cells generate energy, which the researchers said may help explain the reduction in inflammatory activity.
“Taken together, these findings suggest that [physical exercise] attenuates the pro-inflammatory … potential of T cells in EAE mice, by modulating their metabolic profile and, consequently, their activation state,” the scientists wrote.
The vagus nerve plays key roles in regulating automatic bodily processes, including immune activity. In a subsequent set of experiments, the researchers found that the beneficial effects of exercise on disease activity were partly lost in EAE mice whose vagus nerve had been cut (a procedure known as cervical vagotomy).
Cutting the vagus nerve also halted the exercise-associated shift in T-cell activity and metabolism, suggesting that signaling through this nerve plays an important role in linking exercise to changes in immune activity.
“Our findings suggest that the integrity of the vagus nerve may contribute to the beneficial effects of exercise on EAE [disease biology],” the researchers wrote. They noted that therapies aimed at stimulating the vagus nerve could be explored in future studies as a way to influence immune responses in MS.
Small study in patients suggests similar immune effects
While most experiments were conducted in mice, the researchers also ran a small pilot study examining an eight-week exercise program in 18 people with progressive MS.
The exercise-based rehabilitation program led to improvements in clinical and patient-reported outcomes. Participants reported reduced anxiety and improvements in energy and physical quality of life. The researchers also found changes in T-cell metabolism, including enhanced mitochondrial respiration, supporting the idea that similar mechanisms may be at play in people.
“Our findings identify [physical exercise] as a promising disease-modifying intervention capable of reshaping immune-metabolic pathways and reducing synaptic injury in MS and suggest the role of vagal integrity in mediating these beneficial effects,” the scientists wrote.
The researchers called for further studies to explore how these mechanisms might be used to develop new MS therapies. “Future studies integrating clinical, [nervous system], and immunological biomarkers will be essential to translate these insights into personalized therapeutic strategies for people with MS.”
Leave a comment
Fill in the required fields to post. Your email address will not be published.