Zhiye et al. demonstrated in in vitro and in vivo studies that TMAO treatment directly caused cardiac hypertrophy and fibrosis, as evidenced by increased cardiomyocyte size and high levels of hypertrophic markers including atrial natriuretic peptide (ANP) and beta-myosin heavy chain (β-MHC). The gene discussed is NPPA; the disease is cardiac hypertrophy.