Table 1.

	Atherosclerosis	Hypertension	Heart failure	Obesity, T2DM	Chronic kidney disease
Alterations in gut microbiota composition	↑Lactobacillus5 ↓Roseburiam4	↑Firmicutes / Bacteroides ratio67	↑Escherichia coli, Klebsiella pneumonia, Streptococcus viridans	↑Firmicutes36,37,91,93,94 ↓Bacteroides36, 37, 91	↑Firmicutes, Proteobacteria and Actinobacteria131
Alterations in gut microbiota metabolites	↑TMAO8, 9	↑SCFA180	↑TMAO60, 61, 90	↑BAs, SCFA, LPS and TMAO98, 172, 182–184	↑Indoxyl sulfate, 185,186 p-cresol sulfate, 186,187 ammonia and urea, 188 and TMAO59
Proof of concept	Dietary choline/ carnitine ↑TMAO8 DMB suppress TMA/TMAO.65 ↑TMAO associated with unstable plaque and MACE. 22,63,189 Cecal microbial transplantation transmits disease susceptibility.145	Infusion of AngII/TMAO associated with ↑blood pressure 190	↑gut permeability88 ↑TMAO was associated with LV remodelling and poor prognosis60,61,90	↑insulin sensitivity related to vancomycin treatment99 ↑Leptin, GLP1,103–106 PYY102, 105, 106 ↑TMAO was associated with glycemic control. 191	Ammonia disrupt the gut epithelial tight junction131 Elevated TMAO was associated with decreased renal function, renal fibrosis and mortality.59–61,192
Interventions	Diet intervention: ↑Bacteroides and Proteobacteria, ↓Firmicutes 193 Probiotics: ↑LV hypertrophy53 Probiotics: ↑SCFA 168	Diet intervention: high fiber diet is associated with ↓blood pressure.159	Diet: High fiber diet is associated with ↓cardiac hypertrophy and fibrosis.159 Probiotics: attenuate heart failure after myocardial infarction.53	FMT: improve insulin resistance99, 100 and Roseburia.37, 93 Bariatric surgery is associated with ↑BAs and GLP-1120–122 Probiotics: ↑insulin secretion166 ↓body weight and adipose tissue mass172–175	Probiotics: ↓dimethylamine and nitrosodimithylamine.167

T2DM = type 2 diabetes mellitus, TMAO = trymethylamine N-oxide, SCFA = short chain fatty acid, BA = bile acid, LPS = lipopolysaccharide, DMB = 1,3 dimethylbutanol, MACE = major adverse cardiac event, AngII = angiotensin II, LV = left ventricular, GLP-1 = glucagon-like peptide 1, PYY = peptide YY, FMT = fecal microbiota transplantation.