A breakthrough in multiple sclerosis (MS) research suggests that the disease may be triggered by a bacterial infection, illuminating a possible vaccine target for the debilitating condition that causes the body’s own defenses to attack the nervous system.
Dr. Jennifer Linden, a researcher at Weill Cornell Medical College and lead author of the new study, said that the findings may represent the first glimpse of the long-sought cause of MS — an inflammatory disease thought to arise from a combination of genetic and environmental factors. The results suggest that epsilon toxin, a substance produced by certain strains of the foodborne bacterium Clostridium perfringens, can jumpstart disease development by weakening the so-called brain-blood barrier (BBB). In an email to Medical Daily, Linden said that, while more research is needed, this discovery could inspire an entirely new way of dealing with the condition.
“We believe we have very convincing data that supports this theory that epsilon toxin causes MS,” she said. “If this theory is correct, vaccines and antibodies could be developed against epsilon toxin that could prevent MS as well as inhibit disease progression.”
The study, which was presented at the 2014 ASM Biodefense and Emerging Disease Research Meeting in Washington, shows that the epsilon toxin paves way for MS by promoting BBB permeability as well as demyelination — a hallmark symptom of the disease, whereby the outer layer of nerve cells is damaged. With time, this leads to numbness in limbs, partial or complete loss of vision, lack of coordinating, slurred speech, and other neurological symptoms.
"We provide evidence that supports epsilon toxin's ability to cause BBB permeability and show that epsilon toxin kills the brain's myelin producing cells, oligodendrocytes; the same cells that die in MS lesions," Linden explained in a press release. "We also show that epsilon toxin targets other cells types associated with MS inflammation such as the retinal vascular and meningeal cells. Epsilon toxin may be responsible for triggering MS."
Today, MS affects about 400,000 Americans, with nearly 200 new diagnoses reported every week. It is most commonly diagnosed in people between 20 and 50 years of age. Aside from a number of mainstay drugs, the condition is often treated with exercise, balanced nutrition, and other lifestyle interventions.
Linden and her colleagues’ research represents the latest in growing series of attempts to inhibit and reverse the currently incurable condition. Another example is a 2013 study from Oregon Health & Science University, in which scientists show that a single antioxidant may hold the key to eliminating the disease. Similarly, a study from Johns Hopkins University found that vitamin D can block nerve damage associated with MS.
According to Linden, an accompanying analysis of local foods found that nearly three percent were positive for the bacteria expressing the epsilon toxin. Should further research confirm the link between MS and the toxin, this observation could also inspire new food safety guidelines. “These results only say that epsilon producing toxin can be found in commonly purchased food items. More studies are needed to determine how prevalent these bacteria are in food before any guidelines are developed,” she explained. “However, practicing good personal hygiene and following proper food preparation techniques are always beneficial.”
Source: Linden JR, Ma Y, Zhao B, Rumah KR, et al. Epsilon Toxin: An Environmental Cause of Multiple Sclerosis? “ASM Biodefense and Emerging Disease Research Meeting." Clostridium perfringens. 2014.