Abstract
Type 2 diabetes mellitus (T2DM) is associated with cardiovascular disease (CVD) and sodium glucose cotransporter 2 inhibitors, as oral medications for T2DM treatment have shown the potential to improve vascular dysfunction. The aim of this study was to evaluate the ability of canagliflozin (Cana) to relieve CVD in T2DM mice and its possible action mechanism. Mice with diabetic CVD was conducted by a high-fat diet for 24 weeks, followed by oral gavaging with metformin (200 mg/kg/day) or Cana (50 mg/kg/day) for 6 weeks. The result demonstrated that Cana reduced serum lipid accumulation, and decreased the arteriosclerosis index and atherogenic index of plasma. In addition, Cana treatment reduced the circulating markers of inflammation. More importantly, Cana improved cardiac mitochondrial homeostasis and relieved oxidative stress. Moreover, Cana treatment alleviated the myocardial injury with decreasing levels of serous soluble cluster of differentiation 40 ligand and cardiac troponin I. Thus, cardiovascular abnormality was relieved by suppressing fibrosis and basement membrane thickening, while elevating the cluster of differentiation 31 expression level. Importantly, Cana increased the ratio of gut bacteria Firmicutes/Bacteroidetes and the relative abundance of Alistipes, Olsenella, and Alloprevotella, while it decreased the abundance of Mucispirillum, Helicobacter, and Proteobacteria at various taxonomic levels in mice with diabetic CVD. In short, Cana treatment altered the colonic microbiota composition close to the normal level, which was related with blood lipid, inflammation, and oxidative stress, and might play a vital role in CVD. In general, the improvements in the gut microbiota and myocardial mitochondrial homeostasis may represent the mechanism of Cana on CVD treatment.