Inulin from Dioscorea esculenta and Metformin in Combination Ameliorates Metabolic Syndrome in Rats by Altering Short-Chain Fatty Acids

Abstract

Metabolic syndrome (MetS) increases the risk of diabetes and cardiovascular diseases. Several studies have highlighted the role of inulin and metformin in metabolic disorders since insulin resistance and gut microbiota are known to play a role in them. This study was aimed at assessing the effect of the combination of inulin from Dioscorea esculenta (DC) and metformin on insulin resistance, lipid profile, and short-chain fatty acids (SCFAs) in the MetS rat model. Twenty-five rats were divided into 5 groups consisting of one untreated group and four treated groups that received a single dose of streptozotocin (STZ) and a high-fat diet (HFD) for 35 days to induce MetS. Starting on day 14, three of the treated groups; I, M, and Com were administered inulin DC (360 mg/day, orally), metformin (100 mg/KgBW, intraperitoneally), and a combination of inulin DC and metformin (inulin DC; 360 mg/day, orally and metformin; 100 mg/KgBW, intraperioteneally), respectively. The biochemical parameters (HOMA-IR, serum insulin, glucose, HbA1C, cholesterol, triglyceride (TG), low-density lipoprotein (LDL) and SCFAs (butyric acid (BA), propionic acid (PA), and acetic acid (AA)) were evaluated. This study found that the combination of inulin DC and metformin decreased HOMA-IR, serum insulin, glucose, HbA1C, cholesterol, TG, LDL and increased butyric acid and propionic acid but not acetic acid in MetS model. In conclusion, the combination of inulin DC and metformin ameliorates insulin resistance and the lipid profile in MetS model rats was associated with the changes in SCFAs.