Could Imbalance in Gut Bacteria Predict Multiple Sclerosis Severity?

Could an Imbalance in Gut Bacteria Predict MS Severity?

Multiple sclerosis (MS) affects about 2.9 million people worldwide, leading to a wide variety of symptoms as the body’s immune system attacks the central nervous system. While the cause of MS remains unclear, its progression can significantly vary from person to person. In fact, some individuals experience an acute onset, while others deal with slower, more progressive forms of the disease. The severity of MS can change over time, with periods of exacerbation and remission. Given the unpredictable nature of this condition, researchers are continually exploring new ways to predict its severity and identify factors that contribute to its progression. A groundbreaking study recently published by a team from the University of Iowa suggests that an imbalance in gut bacteria may be one of the crucial factors in predicting the severity of MS. Could the health of your gut microbiome hold the key to understanding and potentially controlling MS?

Understanding MS and Its Progression

MS is an autoimmune disease in which the immune system mistakenly attacks the protective covering of nerve fibers, known as myelin, causing inflammation and damage. This damage disrupts communication between the brain and the rest of the body, leading to a range of symptoms that vary greatly between individuals, including fatigue, muscle weakness, and cognitive issues. Over time, MS can lead to permanent disability.

There are many risk factors associated with MS, including genetic predisposition, environmental exposures like viral infections, and lifestyle choices. For example, smoking, vitamin D deficiency, and obesity have all been identified as risk factors that may worsen the disease. However, in recent years, one particular area of interest has emerged: gut health. More specifically, the gut microbiome—an ecosystem of trillions of bacteria living in the digestive tract—has become a focal point in understanding MS and its severity.

The Link Between Gut Bacteria and MS

The human gut microbiome is a complex environment made up of a diverse community of microorganisms, including bacteria, viruses, fungi, and other microbes. This microbiome plays a critical role in digestion, immunity, and even mental health. Recent studies have shown that an imbalance in the gut microbiome, known as dysbiosis, can contribute to various diseases, including autoimmune conditions like MS. In fact, the bacteria present in the gut of people with MS appear to differ significantly from those found in healthy individuals. But could the ratio of specific gut bacteria be used to predict the severity of MS?

This question was explored in a recent study led by Ashutosh K. Mangalam, PhD, an associate professor of pathology at the Carver College of Medicine at the University of Iowa. The study, published in the journal Proceedings of the National Academy of Sciences (PNAS), suggests that the presence of certain gut bacteria may indeed serve as a predictor for the progression and severity of MS.

The Role of Gut Bacteria in MS Severity

In this study, Mangalam and his team analyzed the gut microbiomes of 45 people diagnosed with MS. The researchers discovered that one bacterium, Blautia, was more commonly found in individuals with MS, while levels of Prevotella were significantly lower in comparison. The relationship between these two types of bacteria is particularly intriguing because they seem to have opposing roles in maintaining gut health.

Blautia is known to help maintain gut integrity and reduce inflammation, while Prevotella has been linked to promoting a healthy gut environment. An imbalance in the levels of these two bacteria could be indicative of a potential shift towards a more inflammatory state in the body, which is characteristic of MS. Additionally, the low levels of Prevotella found in MS patients suggest that a deficiency of beneficial bacteria may contribute to the development of MS or its progression.

This imbalance between Blautia and Prevotella is not just theoretical—it has real consequences. According to Mangalam, the findings suggest that the gut microbiome, specifically the balance between these bacteria, could influence inflammatory processes associated with MS. Furthermore, changes in the microbiome could offer insights into how the disease progresses, potentially allowing clinicians to predict the severity of MS in individual patients.

Mouse Model Experiment: A Step Further

Building on their initial findings in human subjects, Mangalam and his team conducted further experiments using a mouse model of MS. In this study, the researchers administered either Blautia, Prevotella, or a control bacterium called Phocaeicola to different groups of mice. The results were striking. Mice that received Blautia developed more severe MS-like symptoms and exhibited greater gut inflammation compared to the other groups. Interestingly, the Blautia-treated mice also showed lower levels of Bifidobacterium, a bacterium known for its gut-health benefits, and higher levels of Akkermansia, a pro-inflammatory bacterium.

This shift in the microbial landscape mirrors what the researchers had observed in humans with MS. According to Mangalam, the increase in Akkermansia and the decrease in Bifidobacterium could serve as important biomarkers for predicting the severity of MS. Akkermansia and Blautia are known to feed on mucin (the mucus that lines the gut), creating a pro-inflammatory environment that could exacerbate MS symptoms.

Implications for Treatment: Can Probiotics Help?

Given the connection between gut bacteria and MS severity, one might wonder if modifying the microbiome through probiotics could help slow disease progression or reduce symptoms. Mangalam cautions that while probiotics—particularly those containing Bifidobacterium—are associated with gut health, it is premature to claim that they could directly affect MS progression. The researchers have not yet tested whether introducing Bifidobacterium to mice could mitigate the severity of MS, though they have found that Prevotella appeared to have a beneficial effect in their experiments.

Nonetheless, Mangalam recommends incorporating a healthy, plant-based diet into the daily routine, as diet plays a crucial role in shaping the gut microbiome. A diet rich in fiber from fruits, vegetables, and whole grains can help support a balanced microbiome, potentially offering benefits for people with MS. Though research is still in its early stages, understanding the relationship between diet, gut health, and MS is an exciting frontier in the search for better treatments.

The Need for Further Research

While these findings are promising, there is still much more to be learned about the gut microbiome's role in MS. As Dr. Barbara Giesser, a neurologist and MS specialist at Pacific Neuroscience Institute, points out, the study highlights the importance of the gut microbiome in MS but emphasizes the need for larger, longitudinal studies in humans. The gut microbiome is highly responsive to external factors like diet and exercise, and more research is needed to determine how these factors interact with MS disease progression.

Conclusion

The discovery of a potential link between gut bacteria imbalances and the severity of multiple sclerosis opens up exciting new possibilities for predicting disease outcomes and even tailoring treatments based on an individual’s microbiome. As research continues to unravel the complexities of the gut-brain connection, it may soon be possible to identify biomarkers that predict MS severity, allowing for more personalized approaches to treatment.

Learn more: https://www.pnas.org/doi/10.1073/pnas.2413953122