title: Inhibition of dipeptidyl peptidase (DPP)-IV and α-glucosidase activities by pepsin-treated whey proteins.
abstract: Inhibitors of the enzymes dipeptidyl peptidase (DPP)-IV and α-glucosidase are two classes of pharmacotherapeutic agents used for the treatment of type 2 diabetes. In the present study, whey protein isolate (WPI), α-lactalbumin, β-lactoglobulin, serum albumin, and lactoferrin hydrolysates obtained by peptic digestion were investigated for their potential to serve as natural sources of DPP-IV and α-glucosidase inhibitors. Although inhibition of DPP-IV activity was observed in all pepsin-treated whey proteins studied, the α-lactalbumin hydrolysate showed the greatest potency with an IC50 value of 0.036 mg/mL. Conversely, only WPI, β-lactoglobulin, and α-lactalbumin hydrolysates displayed some inhibitory activity against α-glucosidase. This study suggests that peptides generated from whey proteins may have dual beneficial effects on glycemia regulation and could be used as functional food ingredients for the management of type 2 diabetes.
authors.affiliation: Faculty of Land and Food Systems Food Nutrition and Health Program, The University of British Columbia , 2205 East Mall, Vancouver, BC, Canada V6T 1Z4.
authors.forename: Isabelle M E
authors.initials: IM
authors.lastname: Lacroix
authors.forename: Eunice C Y
authors.initials: EC
authors.lastname: Li-Chan
mesh_terms: D000818:Animals; D003924:Diabetes Mellitus, Type 2 / Q000201:enzymology*; D018819:Dipeptidyl Peptidase 4 / Q000032:analysis; D054873:Dipeptidyl-Peptidase IV Inhibitors / Q000737:chemistry*; D004791:Enzyme Inhibitors / Q000737:chemistry*; D065089:Glycoside Hydrolase Inhibitors; D006801:Humans; D006868:Hydrolysis; D008894:Milk Proteins / Q000737:chemistry*; D010434:Pepsin A / Q000737:chemistry; D010455:Peptides / Q000737:chemistry; D011492:Protein Hydrolysates / Q000737:chemistry; D051381:Rats; D000067816:Whey Proteins; D000520:alpha-Glucosidases / Q000032:analysis
chemical_list: D054873:Dipeptidyl-Peptidase IV Inhibitors; D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D008894:Milk Proteins; D010455:Peptides; D011492:Protein Hydrolysates; D000067816:Whey Proteins; D000520:alpha-Glucosidases; D018819:Dipeptidyl Peptidase 4; D010434:Pepsin A