Shock to the System

Can traumatic events—such as auto accidents and divorce—trigger multiple sclerosis? A new study suggests that the answer is yes.

By ROMA SUBRAMANIAN

Illustration by Michael HagelbergEvery year for the past 17 years, Jane Welsh—a neuroimmunologist at the Texas A&M University College of Veterinary Medicine and Biomedical Sciences—and her multiple sclerosis (MS) research team have hosted an “English Tea” for the Brazos Valley MS Support Group.

“You read papers and textbooks about [MS], but it’s not until you sit down and chat with people who live with the disease 24/7 that you’re able to get insights into the disease that aren’t readily available,” says Welsh, explaining the basis for the Tea.

One such insight helped spark one of Welsh’s major studies.

“One year [at the Tea], patients said that they noticed that when they got stressed, they had a relapse and their condition worsened,” says Welsh.

Welsh, who’s interested in understanding how viral infections trigger autoimmune diseases such as MS, was then studying how Theiler’s virus induces an MS-like disease in mice. In MS, the immune system mistakenly destroys myelin, the protective covering of nerves. This demyelination damages nerves and causes scar tissue (sclerosis) to form. Demyelination, nerve damage and scar formation block nerve impulse transmission from the brain and spinal cord to the rest of the body, causing neurological symptoms and cognitive disability.

Intrigued by the patients’ observations and studies suggesting a stress–MS link, Welsh and her collaborators (Mary Meagher, Thomas Welsh and Ralph Storts) decided to use mice infected with Theiler’s virus to determine the role of psychological stress in MS.

When the researchers subjected Theiler’s virus–infected mice to various types of psychological stress—for example, stress due to restrained movement or maternal separation—the mice showed increased levels of glucocorticoids. These hormones suppressed the immune system of the mice, resulting in failure to eliminate the virus and then viral persistence, which in turn caused more severe demyelinating disease.

Welsh and her group recently published their work in the journal Neuroimmunomodulation. They found evidence that stressful life events, such as a car accident or a divorce, decrease the immune system’s ability to fight infection. If someone under stress is infected with a myelin-attacking pathogen, the virus takes advantage of the weakened immune system and attacks the myelin around the nerves, which could trigger MS.

“Your state of mind does affect your physical health and vice versa,” Welsh says, reflecting on the results. She indicates that MS patients may benefit from practicing stress-coping techniques such as yoga or meditation.

Welsh’s other collaborative MS studies include investigating how estrogen reduces MS severity (with Farida Sohrabji), how MS therapy might use the protein interferon tau (with Fuller Bazer) and how MS destroys myelin-forming cells (with Jianrong Li).

Interdisciplinary collaborations and grants from the National Institutes of Health and the National Multiple Sclerosis Society—plus a training grant from Texas A&M’s Life Sciences Task Force—have helped the MS research program at Texas A&M to grow.

However, interacting with the Brazos Valley MS support group has given the scientists involved in MS research a sense that their work is worthwhile.

“Working with the group showed me that the long hours spent in the lab would translate into something meaningful for someone living with this terrible disease,” says Mamatha Nayak, Welsh’s past student.

Welsh hopes that by promoting collaboration between researchers and patients, the English Tea will help students understand how scientific research relates to medicine.

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