The Influence of Gut Microbiota on Muscle Degeneration in Muscular Dystrophy

Romualdo Alves^*
*Correspondence: Romualdo Alves, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy, Email:

Introduction

Muscular Dystrophy (MD) refers to a group of inherited diseases characterized by progressive muscle degeneration, weakness, and loss of function. Among the different forms of muscular dystrophy, Duchenne muscular dystrophy (DMD) and Becker Muscular Dystrophy (BMD) are the most common, affecting primarily males and leading to severe disabilities and, in many cases, early mortality. The pathogenesis of muscular dystrophy has traditionally been associated with defects in specific genes involved in muscle structure and function, such as the dystrophin gene in DMD. However, emerging evidence suggests that other factors, including those from the gut microbiota, may play a significant role in modulating disease progression and muscle degeneration.The human gut microbiota is a complex ecosystem of trillions of microorganisms, including bacteria, fungi, and viruses, that reside in the gastrointestinal tract. It plays a crucial role in maintaining overall health, influencing immune responses, metabolic pathways, and even brain function. Recent research has indicated that the gut microbiota may also have an impact on musculoskeletal health, including muscle function and pathology in disorders like muscular dystrophy. This review explores the potential mechanisms by which gut microbiota influences muscle degeneration in muscular dystrophy and its implications for future therapeutic approaches.

Description

The relationship between the gut microbiota and muscle health is an area of growing interest, particularly in the context of age-related muscle loss and muscle diseases such as muscular dystrophy. The gut microbiota affects muscle function through several mechanisms, including modulation of the immune system, regulation of inflammation, and metabolic processes such as the production of short-chain fatty acids (SCFAs). Dysbiosis, which refers to an imbalance in the composition of gut microbiota, has been implicated in various diseases, including autoimmune disorders, metabolic diseases, and neurodegenerative conditions. In the context of muscular dystrophy, dysbiosis could contribute to muscle degeneration through chronic inflammation, altered immune responses, and metabolic disturbances [1].

Another important way that the gut microbiota influences muscle health is through the production of Short-Chain Fatty Acids (SCFAs), which are byproducts of the fermentation of dietary fiber by gut bacteria. SCFAs, such as acetate, propionate, and butyrate, have been shown to have various beneficial effects on muscle function and metabolism. For instance, butyrate has been found to improve mitochondrial function and muscle regeneration by enhancing the activity of muscle satellite cells, which are responsible for repairing and regenerating damaged muscle tissue. In the context of muscular dystrophy, an altered gut microbiota with reduced SCFA production may contribute to impaired muscle regeneration and increased muscle degeneration. This is particularly important because the regenerative capacity of muscle tissue is already compromised in MD due to genetic mutations. Thus, a gut microbiota that produces fewer SCFAs could exacerbate muscle wasting and degeneration in these patients. On the other hand, strategies aimed at enhancing SCFA production, either through dietary interventions or the use of probiotics, could potentially help support muscle repair and reduce disease progression [2].

The gut microbiota is not only involved in immune regulation and metabolism but also plays a role in the brain-muscle communication via the gut-brain-muscle axis. The gut-brain axis is a bidirectional signaling pathway that links the gut microbiota with the central nervous system, influencing behavior, stress responses, and even motor function. There is growing evidence suggesting that the gut microbiota can impact muscle health through this axis by affecting the regulation of neuromuscular function. In individuals with muscular dystrophy, neuromuscular dysfunction is a hallmark of disease progression. For example, in DMD, muscle weakness and loss of muscle coordination are primarily driven by the degeneration of the neuromuscular junction and muscle fibers. Emerging research suggests that gut microbiota imbalances may influence neuromuscular function by altering neurotransmitter levels or by affecting the brain's ability to send proper signals to muscles. In particular, studies have shown that certain gut bacteria can influence the synthesis of neurotransmitters such as serotonin and gamma-aminobutyric acid (GABA), both of which are involved in motor control and muscle function. Therefore, disruptions in the gut microbiota may exacerbate neuromuscular dysfunction and muscle degeneration in MD [3,4].

Dysbiosis, or an imbalance in the gut microbiota, has been implicated in a wide range of diseases, including muscular dystrophy. Several studies have shown that patients with MD exhibit altered gut microbiota profiles, with reduced diversity and an overrepresentation of certain pathogenic bacteria. These changes in the gut microbiota can lead to an overactive inflammatory response, as well as disruptions in metabolic processes, both of which contribute to muscle degeneration. In animal models of muscular dystrophy, researchers have demonstrated that the manipulation of the gut microbiota through antibiotics, prebiotics, or probiotics can impact muscle function and disease progression. For example, supplementation with specific probiotics has been shown to reduce inflammation and improve muscle strength in dystrophic mice, suggesting that microbiota modulation could be a potential therapeutic strategy for MD patients. However, more research is needed to identify the specific microbial species and pathways involved in these effects, as well as to determine the most effective interventions for clinical use [5,6].

Conclusion

The gut microbiota plays a crucial role in the pathogenesis of muscular dystrophy, influencing muscle degeneration through immune modulation, inflammation, metabolic processes, and neuromuscular function. Dysbiosis, or an imbalance in the gut microbiota, has been linked to increased muscle inflammation and impaired muscle regeneration, potentially exacerbating disease progression. Therapeutic strategies aimed at restoring a healthy gut microbiota, such as the use of probiotics, prebiotics, or dietary interventions, hold promise for improving muscle function and slowing down the progression of muscular dystrophy. However, further research is necessary to fully understand the complex mechanisms involved and to develop personalized treatments for MD patients based on their unique microbiota profiles.

Acknowledgement

None.

Conflict of Interest

There are no conflicts of interest by author.

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