Dietary flaxseed oil rich in omega 3 suppresses severity of type 2 diabetes mellitus via anti inflammation and modulating gut microbiota in rats
Background Type 2 diabetes mellitus (T2DM) is closely associated with hyperglycemia, abnormal lipid profiles, chronic low grade inflammation and gut dysbiosis. Dietary intervention plays a crucial role in the control of diabetes. Flaxseed oil (FO) a plant derived omega 3 (o 3) polyunsaturated fatty acids (PUFAs) is rich in a linolenic acid (ALA) which has been proved to benefit for chronic metabolic disease. However, the exact effects of dietary FO on T2DM remains largely unclear. Methods In the present study, SD rats were randomly allocated into four groups: pair fed (PF) with corn oil (CO) group (PF/CO) DM with CO group (DM/CO) PF with FO group (PF/FO) DM with FO group (DM/FO) A diabetic rat model was generated by a single intraperitoneal injection of streptozotocin nicotinamide (STZ NA) After 5 weeks of intervention, rats were euthanized and associated indications were investigated. Results Dietary FO significantly reduced fasting blood glucose (FBG) glycated hemoglobin (GHb) blood lipid, plasma lipopolysaccharide (LPS) interleukin (IL) 1b, tumor necrosis factor (TNF) a, IL 6, IL 17A and malondialdehyde (MDA) compared to control group, respectively. Moreover, body mass (BM) and superoxide dismutase (SOD) in DM/FO group were dramatically increased respectively, compared with those in DM/CO group. But insulin (INS) and homeostasis model assessment of insulin resistance (HOMA IR) remained no significant difference between DM/CO group and DM/FO group. Sequencing analysis of gut microbiota showed a reduction in the relative abundance of Firmicutes and Blautia as well as a reduction in the ratio of Bacteroidetes Firmicutes in DM/FO group compared to DM/CO group. An elevation in the relative abundance of Bacteroidetes and Alistipes were detected in DM/FO group. Acetic acid, propionic acid and butyric acid belonging to short chain fatty acids (SCFAs) as gut microbiota metabolites, were dramatically increased after FO intervention. Correlation analysis revealed that the relative abundance of Firmicutes and Blautia were positively correlated with IL 1b, TNF a, IL 6, IL 17A or LPS, respectively. Additionally, Bacteroidetes and Alistipes were negatively correlated with LPS. Conclusions Taken together, dietary FO ameliorated T2DM via suppressing inflammation and modulating gut microbiota, which may potentially contribute to dietary control of diabetes.
Lipids in Health and Disease