The Role of the Microbiome in the Pathogenesis and Treatment of Asthma

Saccharomyces boulardii alleviates allergic asthma by restoring gut microbiota and metabolic homeostasis via up-regulation of METTL3 in an m6A-dependent manner

BACKGROUND

Allergic asthma is a heterogeneous disease and new strategies are needed to prevent or treat this disease. Studies have shown that probiotic interventions are effective in preventing asthma. Here, we investigated the impact of Saccharomyces boulardii (S. boulardii) on ovalbumin (OVA)-induced allergic asthma in mice, as well as the underlying mechanisms.

METHODS

First, we constructed a mouse asthma model using OVA and given S. boulardii intervention. Next, we measured N6-methyladenosine (m6A) levels in lung injury tissues. 16 s rRNA was employed to identify different gut microbiota in fecal samples. The analysis of differential metabolites in feces was performed by non-targeted metabolomics. Pearson correlation coefficient was utilized to analyze correlation between gut microbiota, metabolites and methyltransferase-like 3 (METTL3). Finally, we collected mouse feces treated by OVA and S. boulardii intervention for fecal microbiota transplantation (FMT) and interfered with METTL3.

RESULTS

S. boulardii improved inflammation and oxidative stress and alleviated lung damage in asthmatic mice. In addition, S. boulardii regulated m6A modification levels in asthmatic mice. 16 s rRNA sequencing showed that S. boulardii remodeled gut microbiota homeostasis in asthmatic mice. Non-targeted metabolomics analysis showed S. boulardii restored metabolic homeostasis in asthmatic mice. There was a correlation between gut microbiota, differential metabolites, and METTL3 analyzed by Pearson correlation. Additionally, through FMT and interference of METTL3, we found that gut microbiota mediated the up-regulation of METTL3 by S. boulardii improved inflammation and oxidative stress in asthmatic mice, and alleviated lung injury.

CONCLUSIONS

S. boulardii alleviated allergic asthma by restoring gut microbiota and metabolic homeostasis via up-regulation of METTL3 in an m6A-dependent manner.

Unraveling the Complexity of Asthma: Insights from Omics Approaches

Asthma is a heterogeneous respiratory disease that represents a substantial social and economic burden [...].

Can Therapeutic Targeting of the Human Microbiome Influence Asthma Management? A Pro/Con Debate

Asthma is a clinically heterogeneous disease, and despite substantial improvements in therapies, there remains an unmet need for well-tolerated, effective treatments. Observational studies have demonstrated that alterations in the respiratory and gut microbiome are associated with the development of asthma and its severity. These findings are supported by preclinical models demonstrating that respiratory and gut microbes can alter airway inflammation. Therapeutic approaches to target the human microbiome have been increasingly applied to a wide range of acute and chronic diseases, but there are currently no microbiome-based therapeutics approved for the treatment of asthma. This clinical commentary addresses the future role of microbiome-based therapeutics in asthma management from both a pro and con perspective. We examine (1) the prospects for clinical studies demonstrating a causal relationship between the human microbiome and the severity of asthma; (2) the challenges and potential solutions for designing, testing, and implementing a microbiome-based therapeutic; and (3) the possibility of microbiome-based therapeutics for conditions comorbid to asthma. We conclude by identifying research priorities that will help determine the future of microbiome-based therapeutics for the management of asthma.

Immunomodulatory action of synbiotic comprising of newly isolated lactic acid producing bacterial strains against allergic asthma in mice

Given the reported role of gut-microbiota in asthma pathogenesis, the present work was carried to evaluate immunomodulatory action of newly isolated lactic acid producing bacterial strains Bifidobacterium breve Bif11 and Lactiplantibacillus plantarum LAB31 against asthma using ovalbumin (OVA) based mouse model. Our results show that both strains modulate Th2 immune response potentially through production of short chain fatty acids (SCFAs), resulting in suppression of OVA-induced airway inflammation. Furthermore, synbiotic comprising of both strains and prebiotic, Isomaltooligosaccharide exhibited superior potential in amelioration of OVA-induced airway inflammation through improved modulation of Th2 immune response. Further, synbiotic protects against OVA-induced mucus hyper-production and airway-hyperresponsiveness. Such protection was associated with normalization of gut microbiome and enhanced production of SCFAs in cecum which correlates closely with population of T-regulatory cells in spleen. Overall, our novel synbiotic possesses the ability to fine-tune the immune response for providing protection against allergic asthma.