title: Nutritional supplements modulate fluorescent protein-bound advanced glycation endproducts and digestive enzymes related to type 2 diabetes mellitus.
abstract: BACKGROUND
  Chronic hyperglycemia enhances the formation of advanced glycation endproducts (AGEs) and reactive oxygen species (ROS), contributing to diabetic complications. Thus, controlling blood glucose levels, inhibiting the formation of AGEs and reducing ROS are key therapeutic targets in early stage type 2 diabetes.
  
  
  METHODS
  The inhibitory effects of seven commercial liquid nutritional supplements against carbohydrate hydrolysing enzymes, α-amylase and α-glucosidase, was determined by dinitrosalicylic (DNS) reagent and p-nitrophenyl-α-D-glucopyranoside solution, respectively. Antiglycation activity was determined using the formation of fluorescent protein-bound AGEs. Total phenolic and flavonoid content and antioxidant properties (1,1-diphenyl-2-picrylhydrazyl antioxidant activity (DPPH) and ferric reducing antioxidant power (FRAP)) were determined for correlation among these components and inhibitory activities.
  
  
  RESULTS
  Samoan noni juice showed the greatest inhibitory effects against α-amylase, whereas chlorophyll extracts showed the greatest inhibitory effect against α-glucosidase. Inhibition of α-glucosidase correlated with TFC (r(2) = 0.766; p < 0.01) and FRAP (r(2) = 0.750; p < 0.01) whereas no correlation was observed for α-amylase inhibition. All supplements inhibited fluorescent protein-bound AGEs, with the greatest effect exerted by Olive Leaf Extract, Blood Sugar Support (IC50 = 0.5 mg/ml). The IC50 values negatively correlated with TPC (r(2) = -0.707; p < 0.001) and DPPH scavenging activities (r(2) = 0.515; p < 0.05).
  
  
  CONCLUSIONS
  The findings of this study highlight the potential of liquid nutritional supplements in managing and treating type 2 diabetes mellitus.
authors: School of Pharmacy and Medical Sciences, University of the South Australia, Adelaide, SA, 5001, Australia.
authors: Emily R
authors: ER
authors: Koch
authors: School of Pharmacy and Medical Sciences, University of the South Australia, Adelaide, SA, 5001, Australia. permal.deo@unisa.edu.au.
authors: Permal
authors: P
authors: Deo
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D003924:Diabetes Mellitus, Type 2; D019587:Dietary Supplements; D017127:Glycation End Products, Advanced / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D008164:Luminescent Proteins / Q000737:chemistry / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D000516:alpha-Amylases / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D017127:Glycation End Products, Advanced; D008164:Luminescent Proteins; D010936:Plant Extracts; D000516:alpha-Amylases
keywords: Antiglycation; Antioxidant activities; Flavonoids; Liquid nutritional supplements; Phenolic; α-amylase; α-glucosidase