The Emerging Role of Microbiome in Cardiovascular Diseases

Cardiovascular disease (CVD) has become one of the leading causes of poor lifelong health and well-being. Meanwhile, the microbiome has emerged as one of the key determinants of human cardiometabolic homeostasis and the risk of CVD. While the clustering of the microbiome into phylum ratios or enterotypes has been correlated to specific disease phenotypes and population characteristics, the composition of a typical ‘healthy human microbiome’ is yet to be defined. Several population-based studies have shown an association between certain microbial species with CVD, although the inconsistencies have made the interpretation of such associations very difficult as it is not possible to pinpoint microbial populations associated with CVD. However, here we discuss current evidence on the role of the microbiome and its metabolites on the risk of CVD. We further explore current clinical studies investigating prebiotics and probiotics as potential therapeutic targets to modulate the microbiome for the benefit of the host to prevent cardiometabolic diseases. We highlight that further work to understand the role of specific species/sub-species, strains and polymorphisms within those strains, as well as microbial gene expression profiles and their respective metabolites is required. Coupled with high-resolution metagenomics and metabolomics as well as a unified approach in characterising common gut microbial communities based on global population observations, this would provide better indicators of disease phenotype and a better framework for a divergence to dysbiosis. The challenges that will need to be overcome in order to define a healthy microbiome and advance the clinical use of prebiotics and probiotics as well as faecal microbiota transplantation will also be discussed.

Keywords: Bile acids, Bacteroidetes, Cholesterol, Enterotypes, Faecal microbiota transplantation, Firmicutes, Microbiota, Prebiotics, Probiotics, Short chain fatty acids, TMAO.