Title : Discovery and advancement of gut microbiome-based live biotherapeutics for MASLD therapy
Abstract:
Background and Aims: Metabolic Dysfunctional-Associated Steatotic Liver Disease (MASLD) emerges as a hepatic manifestation, characterised by excessive lipid accumulation and other intertwined metabolic risk factors such as obesity and type 2 diabetes. Recent evidence highlights a pivotal role of the gut microbiome in MASLD pathogenesis, where alterations in microbial composition and function contribute to disrupted gut barrier integrity, endotoxemia, bile acid dysregulation, and aberrant metabolite production. These microbiome-driven mechanisms influence hepatic lipid metabolism, inflammation, and fibrosis progression, positioning the gut–liver axis as a critical determinant of disease onset and severity. Consequently, the gut microbiome has emerged as a promising and modifiable therapeutic target for MASLD intervention.
Methods: To decode the gut–liver axis, paired faecal and liver samples were collected and proceeded for metagenomic DNA extraction followed by 16S rRNA and ITS2–4 sequencing. In parallel, a diet-induced MASLD mouse model was developed that helps us to achieve longitudinal profiling of dysbiosis. Cross-cohort analysis of human and mouse gut microbiome revealed core health-associated taxa consistently depleted in both species, which were subsequently isolated to uncover key functional drivers.
Results: We identified core health-associated genera consistently depleted across human MASH cohorts and murine models, underscoring their protective role in gut homeostasis. Further isolation and genomic mining of health-associated taxa uncovered a novel bioactive peptide with therapeutic potential that has not been reported so far. Next, we identified a consortium of novel bacterial species characterised by significant differential abundance between healthy and diseased cohorts. To facilitate microbial restoration, these taxa were assembled into a therapeutic consortium based on their predicted metabolic synergy. This ecological foundation was complemented by the successful engineering of Escherichia coli Nissle 1917 to function as a localised delivery vehicle. Specifically, EcN was programmed to express a novel therapeutic peptide fused to a targeted secretion signal, enabling the robust export of the peptide into the gastrointestinal milieu. Cell-free supernatant of our constructed recombinant strain demonstrated a significant reduction in triglyceride accumulation in a hepatic steatosis cell model, indicating improved lipid homeostasis. In vivo administration of data-driven consortia and recombinant strain elicited a robust metabolic rescue, as evidenced by reduced body weight, accelerated glucose clearance, enhanced insulin sensitivity upon HFD and a pronounced reduction in serum triglyceride levels and hepatic injury markers (ALT and AST) in dietary induced mice model.
Conclusion: This study establishes a novel, dual-component therapeutic framework that integrates microbiome restoration with engineered peptide delivery, each independently demonstrating efficacy in ameliorating metabolic dysfunction. By linking dysbiosis correction to functional therapeutic potential, this work addresses a critical gap in MASLD management and lays the foundation for future combinatorial interventions with enhanced translational relevance.
