Glucose lowering effects by sago (Metroxylon sagu Rottb) resistant starches Type 2 and 4 in spontaneously type 2 diabetes, Goto kakizaki rat

Abstract

The beneficial effects of resistant starch (RS) consumption on health in terms of reducing postprandial hyperglycemia are evident. However, the potential of local Sarawak sago RS in regulating glucose has not been extensively studied. This study aims to identify glucose lowering effects of Sarawak sago RS namely, native unmodified (RS2) and chemically modified (RS4). An oral glucose tolerance test was performed before and after one-month treatment with sago RS2 and RS4 in spontaneously type 2 diabetes, goto kakizaki rat. The mechanisms involved were further explored by screening the in vitro inhibitory activities of α-Glucosidase and DPP-IV. Histopathology examination for pancreas, kidney and liver tissues was performed in response to sago RS treatment using hematoxylin and eosin (H&E) staining.The blood glucose area under the curve (AUC) in RS-treated groups was decreased and significant in RS2-treated group (p<0.05). Improved insulin AUC and higher glucagon like peptide (GLP-1) levels were observed in all RS-treated groups (p<0.05). Sago RS2 and RS4 might have potential roles in regulating glucose via α- Glucosidase and DPP-IV inhibitory activities by reducing glucose absorption in the intestine. For histopathology study, although insignificant, sago RS2 and RS4 attenuated lesion scores of pancreatic tissue whereas the liver and kidney tissues significantly showed lesser lesion scores as compared to the control diabetic group suggesting the potential of RS in reducing cell degeneration which indeed requires further validation.Findings of this study suggests the therapeutic potential of sago RS in the T2D management which may justify further investigation to be done.