Analysis of Short-Chain Fatty Acids and Association with Glucagon-Like Peptide-1 in Healthy, Obese, Prediabetes and Type 2 Diabetes Individuals

Abstract

Context: Short-chain fatty acids (SCFAs) play a critical role in host metabolism, both directly and through specific G protein-coupled receptors, and may provide a link between glucose and lipid metabolism. This study aimed to compare fecal SCFA concentrations and to evaluate associations between SCFAs and glucagon-like peptide 1 (GLP-1) in individuals with type 2 diabetes (T2DM), prediabetes, obesity, and health. Subjects and Methods: The study included 60 volunteers in four groups: T2DM (n= 15), prediabetes (n= 15), obesity (n= 15), and healthy individuals (n= 15). We analyzed fecal SCFA and GLP-1 concentrations by HPLC-UV and ELISA method, respectively. Results: In comparison to healthy individuals, obese, prediabetic and T2DM exhibited notably elevated total SCFA levels respectively (p=0.019, p=0.017, p=0.024). Acetic acid concentration showed an increase in both obese and prediabetic groups compared to the healthy group (p=0.02, p=0.017). Butyric acid concentration was elevated in T2DM and prediabetic groups in comparison to both healthy and obese groups (p=0.024, p=0.017, p=0.07, p=0.56). The GLP-1 levels significantly decreased in the obese and prediabetic groups compared to the healthy and T2DM groups (p=0.00, p=0.021, p=0.000, p=0.005). GLP-1 was correlated with acetic acid, butyric acid, and the total SCFA concentrations in the T2DM and obese groups (r= 0.479, p= 0.098; r= 0.441, p= 0.099; r= 0.654, p= 0.015, respectively) while there was no correlation in the prediabetic group. Conclusion: Our results extend the knowledge on the alteration of SCFA levels in the states of obesity, prediabetes, and T2DM and enrich the understanding of the relationship between SCFAs and GLP-1.