The Role of Human Microbiota in Myasthenia Gravis: A Narrative Review

• Published in: Neurology International
• Main Authors: Giuseppe Schirò, Salvatore Iacono, Carmela Rita Balistreri
• Format: Article
• Language: English
• Published: MDPI AG 2023-03-01
• Subjects: myasthenia gravis; gut–brain axis; inflammation; oral microbiota; gut microbiota; Western diet
• Online Access: https://www.mdpi.com/2035-8377/15/1/26

Myasthenia gravis (MG) is an autoimmune neuromuscular disease characterized by fluctuating weakness of the skeletal muscles. Although antibodies against the neuromuscular junction components are recognized, the MG pathogenesis remains unclear, even if with a well-known multifactorial character. However, the perturbations of human microbiota have been recently suggested to contribute to MG pathogenesis and clinical course. Accordingly, some products derived from commensal flora have been demonstrated to have anti-inflammatory effects, while other have been shown to possess pro-inflammatory properties. In addition, patients with MG when compared with age-matched controls showed a distinctive composition in the oral and gut microbiota, with a typical increase in <i>Streptococcus</i> and <i>Bacteroides</i> and a reduction in <i>Clostridia</i> as well as short-chain fatty acid reduction. Moreover, restoring the gut microbiota perturbation has been evidenced after the administration of probiotics followed by an improvement of symptoms in MG cases. To highlight the role of the oral and gut microbiota in MG pathogenesis and clinical course, here, the current evidence has been summarized and reviewed.