| ▲ Research results have been announced that multiple sclerosis can be caused by toxins in the gut microbes. (Photo = DB) |
[메디컬투데이=한지혁 기자] A study has been published that multiple sclerosis can be caused by toxins in the gut microbes.
A study published in The Journal of Clinical Investigation found that toxins produced by gut bacteria can cause multiple sclerosis.
Multiple sclerosis is a chronic autoimmune disease that affects the central nervous system. According to statistics, about 2.8 million people worldwide have been diagnosed with multiple sclerosis, and the number is increasing.
In multiple sclerosis, a patient’s immune system attacks the myelin covering nerve fibers, which can cause symptoms such as muscle weakness, cramps, tingling and burning sensations, urinary problems, vision problems, fatigue, and dizziness.
‘Relapsing-remitting multiple sclerosis’, the most common form of multiple sclerosis, accounts for 85% of all cases and is characterized by repeated increases and decreases in symptoms. Although the exact cause is still unknown, many experts speculate that genetic and environmental factors may contribute to the development of the disease.
In this study, the researchers found that epsilon toxin produced by bacteria living in the small intestine can lead to the development of multiple sclerosis and cause persistent symptoms.
The gut microbiome consists of trillions of microorganisms living in the digestive tract, most of which are bacteria, but viruses, fungi, and protozoa also exist. These gut microbes are generally essential for maintaining health, but losing the proper balance can lead to a variety of problems, some leading to autoimmune diseases.
Changes in the gut microbiome are common in patients with multiple sclerosis. The research team found that there is a high probability that a bacterium called ‘Clostridium perfringens’ is present in the intestines of patients with multiple sclerosis.
C. perfringen produces epsilon toxin, which helps inflammatory cells access the central nervous system through blood vessels in the brain.
After taking fecal samples from multiple sclerosis patients and normal participants, they analyzed them through polymerase chain reaction (PCR) to identify the ‘ETX’ gene that produces epsilen toxin.
They found that the ETX gene was found in 61% of fecal samples from patients with multiple sclerosis, compared to only 13% of normal participants. Additionally, patients with multiple sclerosis were more likely to have C. perfringen predominate in their gut microbiome than age- and sex-matched healthy controls.
Next, the researchers conducted an experiment in a mouse model to investigate whether injection of epsilon toxin caused symptoms of multiple sclerosis.
Mice injected with ETX exhibited central nervous system demyelination similar to that seen in patients with multiple sclerosis. In particular, lesions in the cerebellum, a commonly affected area in multiple sclerosis, were prominent.
C. perfringen is known to produce epsilon toxin only during periods of rapid growth. The researchers explained the change in symptoms of relapsing-remitting multiple sclerosis by the fact that symptoms do not occur when the bacteria do not produce epsilon toxin.
They said that developing therapies that target these mechanisms would be the next step in their research, which would previously require clinical trials in humans.
Medical Today Reporter Han Ji-hyeok (hanjh3438@mdtoday.co.kr)
[저작권자ⓒ 메디컬투데이. 무단전재-재배포 금지]
