Vascular dysfunction often precedes the development of cardiovascular disease in which data from our lab and others suggest a role of the gut microbiome in the development of this defect. In a pilot study of healthy humans, we observed that the spore-based probiotic, Bacillus Subtilis DE111(DE111), improved reactive hyperemia index (RHI) scores, indicating improved vascular dilation. To further explore whether DE111 impacts cardiovascular function, the current study examined its efficacy in a diet-induced obesity model in mice. Male C57/BJ mice were fed a standard diet (SD; n=24) or Western diet (WD; n=24) for 8 weeks to induce vascular dysfunction and were then further divided such that (n=12) half of the animals on each diet received 1billion colony forming units per day (CFU/d) of DE111. Weekly body weight was measured until termination at 6 months of age. WD and WD+DE111 mice exhibited similar increases in body weight (SD: 31.2±2.3 vs WD: 47.4±3.3 and WD+DE111: 45.7±4.0) and impairments in glucose tolerance compared to SD mice (SD: 237.1±68.0 vs WD: 410±26.9 and WD+DE111: 460±116.8, plt;0.05). A 28% decrease in vessel dilation was observed with mice on a WD as compared to mice on a SD after addition of the endothelial-dependent dilator acetylcholine (AUC, 918.3±49.25, plt;0.05). However, the addition of DE111 improved endothelial mediated vessel dilation in mice fed a WD+DE111 (AUC, 991.7±47.9, plt;0.05). This increase was observed independent of body weight changes and improvement in glucose tolerance. In conclusion, the addition of DE111 increased endothelial-dependent dilation in mice fed a WD. Further analyses are underway to establish the mechanisms of this gut-vasculature crosstalk, but our animal and human studies both suggest that the novel probiotic, DE111 may support cardiovascular health.
