Gut–Heart Axis: Microbiome Involvement in Wild-Type Transthyretin Amyloidosis

Cardiac amyloidosis is a rare and progressive condition characterized by the extracellular deposition of amyloid fibrils in multiple organs. Wild-type transthyretin amyloidosis (ATTR-wt) is the most common type affecting subjects above 60 years old. Recent and growing evidence suggests a potential link between GM and cardiac amyloidosis. In this scenario, the aim of the present study is to characterize the gut microbiota (GM), related metabolites and inflammatory biomarkers in ATTR-wt patients. In the ATTR patients we identified Prevotella_9 as the core OTUs (Operational Taxonomic Unit) of this group, alongside Prevotella 7, Prevotellaceae_UCG-003 and Prevotellaceae_NK3B31. In addition, there were increased levels of long fatty acids, including tetradecanoic, hexadecanoic and octadecanoic acids, in the ATTR group. The data obtained suggest that ATTR patients have an altered gut microbiota that could be used as a potential biomarker in metabolic and cardiovascular diseases, as well as a potential predictor of adverse prognosis in ATTR patients. In addition, the intestinal dysbiosis in ATTR patients could be associated with low-grade endotoxemia promoting a pro-inflammatory state due to the translocation of bacterial components, such as LPS (lipopolysaccharide), into blood circulation.