桑原 政成

AIM: Gut microbiota dysbiosis causes atherosclerosis. Patients with atherosclerosis and type 2 diabetes mellitus (T2D) often have low Bacteroides abundance, potentially increasing atherosclerosis risk. This study investigated the association between low Bacteroides abundance and endothelial dysfunction in patients with T2D. METHODS: The relationship between the relative Bacteroides abundance in fecal gut microbiota, assessed by 16S ribosomal RNA analysis, and the reactive hyperemia index (RHI) was investigated in 93 patients with T2D (68 men and 25 women). Clinical parameters, including plasma short-chain fatty acids and inflammatory markers, were also examined. Heatmap analysis compared lower Bacteroides group vs. upper Bacteroides group. RESULTS: Natural log-transformed RHI (Ln-RHI) was positively correlated with Ln-relative Bacteroides abundance (p < 0.05). The low Bacteroides group had a considerably lower Ln-RHI than the high group (p = 0.038). Plasma acetate content was correlated with relative Bacteroides abundance (p = 0.036) but not with Ln-RHI content. The low Bacteroides group tended to have higher high-sensitivity C-reactive protein levels than the high group (p = 0.069). No other bacterial differences between the groups were associated with the RHI. CONCLUSIONS: Low Bacteroides abundance is associated with low RHI and may be associated with the risk of atherosclerosis in patients with T2D.