JAN 30, 2018 09:52 AM PST

Testosterone Makes A Difference When It Comes to Multiple Sclerosis

WRITTEN BY: Kara Marker

High levels of testosterone in men is part of the reason that they are less likely than women to develop multiple sclerosis (MS), an autoimmune disease that affects the brain and spinal cord. From Northwestern University, scientists studied MS in mice to uncover the protective effect of testosterone.

Photomicrograph of a demyelinating MS-Lesion. Immunohistochemical staining for CD68 highlights numerous macrophages (brown). Credit: Marvin 101

In MS, T cells of the immune system attack the myelin sheath, a protective layer of insulation that surrounds nerve fibers in the central nervous system, which includes the brain and spinal cord. Nerve impulses without proper insulation are disrupted while traveling to and from the brain and spinal cord, producing symptoms that range from mild to severe. Fatigue, numbness or tingling, walking difficulty, muscle spasms, vision problems, bladder problems, cognitive changes, and depression are just a few of the symptoms that commonly affect people with MS.

MS primarily occurs in two different forms. The first, relapsing-remitting MS, is the most common course of MS, characterized by periods of MS symptoms followed by periods of recovery. The second, primary progressive is a type of MS that gets worse over time without periods of recovery.

Experts estimate that 400,000 people in the United States and 2.5 million people across the globe are affected by MS. The exact cause is still unknown, but it is believed to be a combination of genetics and environment influences. Women are three or four times more likely than men to have MS, tend to develop MS earlier, and are more likely to have the relapsing-remitting form of the disease. Men are more likely to develop primary progressive form of the disease, which scientists associate with a natural reduction of testosterone levels that occurs with age.

In the Northwestern University study, researchers used a mouse model of MS, which is similar to how MS affects humans. They found that testosterone triggers the production of a “guardian molecule,” cytokine IL-33. IL-33 activates several other chemicals that prevent Th17 cells from attacking the myelin sheath. In the study, researchers successfully relieved female mice of their MS symptoms when treated with IL-33.

"Because testosterone levels are seven-to-eight times lower in adult women compared to men, we speculate there are insufficient levels in females to activate this protective pathway," explained lead study author Melissa Brown. "But we showed we can activate the pathway with the guardian molecule, IL-33."

Existing therapies for MS often involve suppressing the immune system, which might diminish the autoimmune attack on the myelin sheath but can also leave MS patients vulnerable to infections.

"This suggests a mechanism for the reduced incidence of multiple sclerosis and other autoimmune diseases in males compared to females," Brown said. "These findings could lead to an entirely new kind of therapy for MS, which we greatly need."

The present study was published in the journal Proceedings of the National Academy of Sciences.

Sources: Discovery MS, National Multiple Sclerosis Society, Northwestern University

About the Author
  • I am a scientific journalist and enthusiast, especially in the realm of biomedicine. I am passionate about conveying the truth in scientific phenomena and subsequently improving health and public awareness. Sometimes scientific research needs a translator to effectively communicate the scientific jargon present in significant findings. I plan to be that translating communicator, and I hope to decrease the spread of misrepresented scientific phenomena! Check out my science blog: ScienceKara.com.
You May Also Like
OCT 01, 2018
Immunology
OCT 01, 2018
Transplanting Fecal Matter
A study published in the New England Journal of Medicine provides insight into the effectiveness of a fecal microbiome transplant when compared to antibiotic therapy....
OCT 09, 2018
Drug Discovery
OCT 09, 2018
'Copper Antibiotic Peptide' Effective in Eradicating Tuberculosis
The bacterium responsible for Tuberculosis has found a way to avoid antibiotics by hiding inside the macrophages which are the specific immune cells that a...
OCT 16, 2018
Drug Discovery
OCT 16, 2018
Potential Targeted Treatment for Crohn Disease
Emerging as a global disease with rates increasing the past 5 decades, Crohn’s disease (CD) is the chronic inflammation of the intestinal tract. Now,...
NOV 23, 2018
Health & Medicine
NOV 23, 2018
Fatty NK Cells Can't Target Cancer
Scientists have found yet another link between obesity and cancer. Obesity has long been known to increase the risk of coronary heart disease, stroke, type...
DEC 04, 2018
Immunology
DEC 04, 2018
Why is Skin Cancer so Elusive?
A pathway involved in skin cancer reveals a potential immunotherapy target...
DEC 11, 2018
Immunology
DEC 11, 2018
Autoimmunity Caused By Genetic Mutation
Research reveals a genetic mutation causes a protein binding site to alter its structure resulting in the development of chronic inflammation and autoimmunity...
Loading Comments...