Hypoglycemic effects of white hyacinth bean polysaccharide on type 2 diabetes mellitus rats involvement with entero-insular axis and GLP-1 via metabolomics study

Abstract

The present study aimed to investigate the potential effects of white hyacinth bean polysaccharide (WHBP) against type 2 diabetic mellitus (T2DM) which was established by high-glucose/high-fat for 8 weeks, combined with a low-dose streptozotocin (STZ) injection. Our results showed that WHBP behaved the hypoglycemic effect by attenuating fasting blood glucose in vivo. WHBP-mediated anti-diabetic effects associated with the attenuation of insulin resistance and pancreatic impairment, as evidenced by the mitigation of pathological changes, inflammatory response and oxidative stress in the pancreas of T2DM rats. Meanwhile, gut protection was also shown during WHBP-mediated anti-diabetic effects, and glucagon-like peptide-1 (GLP-1), a mediator of the entero-insular axis, was observed to be elevated in both gut and pancreas of WHBP groups when compared to DM group, suggesting that hypoglycemic effects of WHBP were implicated in gut-pancreas interaction. Subsequently, untargeted metabolomics analysis performed by UPLC-QTOF/MS and showed that WHBP administration significantly adjusted the levels of 40 metabolites when compared to DM group. Further data concerning pathway analysis showed that WHBP administration significantly regulated the phenylalanine metabolism, tryptophan metabolism, arginine and proline, isoleucine metabolism, and glycerophospholipid metabolism in T2DM rats. Together, our results suggested that WHBP performed hypoglycemic effects and pancreatic protection linked to entero-insular axis involvement with GLP-1 and reversed metabolic disturbances in T2DM rats.

Keywords: Entero-insular axis; Hypoglycemic effect; Metabolomics; Type 2 diabetic mellitus; White hyacinth bean polysaccharide.