Imidazole Propionate is Increased in Diabetes and Associated with Stool Consistency

BACKGROUND: Imidazole Propionate (ImP) is a new marker of Type 2 diabetes mellitus (T2DM), which can induce impaired glucose metabolism and weaken the efficacy of metformin. An extensive exploration into literature suggests that ImP may be associated with stool consistency. PURPOSE: Through an in-depth study of the relationship between stool consistency, bile acids, fecal microbiota and ImP, we intend to explore the mechanism driving the ImP content difference in T2DM. PATIENTS UNDER STUDY AND METHODS: This is a single-center, prospective, cross-sectional study. Plasma ImP and stool consistency were analyzed among 96 diabetic subjects and 45 healthy subjects. All subjects were divided into the stool consistency normal (N) group and the stool consistency abnormal group, of which the abnormal group was sub-divided into the hard stool (H) group and the soft stool (S) group. After identifying the correlation between ImP and stool consistency, we analyzed the influence of bile acids and fecal microbiota on ImP in diabetic subjects. RESULTS: For T2DM patients, the ImP level of the abnormal stool consistency group was significantly higher than that of the normal stool consistency group (P < 0.001). Results were verified in 45 healthy subjects (P = 0.002). ImP was significantly associated with taurocholic acid (TCA) (P = 0.003) in feces, taurodeoxycholate (TDCA) (P = 0.003), glycochenodeoxycholate (GCDCA) (P = 0.021), and glycocholic acid (GCA) (P = 0.031) in plasma. The Shannon index of Group N was significantly higher than that of Group H (P = 0.041) and Group S (P = 0.003). CONCLUSION: ImP was higher in diabetic patients with abnormal stool consistency than in those with normal stool consistency, which was related to the proportion of bile acids and fecal microbial structure. These findings may improve our understanding of ImP and contribute to the treatment of T2DM by improving stool consistency.