title: In vitro inhibition of dipeptidyl peptidase IV by peptides derived from the hydrolysis of amaranth (Amaranthus hypochondriacus L.) proteins.
abstract: Bioactive compounds present in foods could potentially have beneficial effects on human health. In this study we report the in vitro inhibitory capacity of peptides released from amaranth seed proteins after enzymatic digestion, against dipeptidyl peptidase IV (DPPIV); an enzyme known to deactivate incretins, hormones involved in insulin secretion. Other seeds, such as soybean, black bean, and wheat were also tested. The highest inhibition of DPPIV was observed with amaranth peptides released after simulated gastrointestinal digestion, showing an IC(50) of 1.1mg/mL in a dose-dependent manner. In silico tryptic digestion of amaranth globulins was carried out releasing peptides larger than 13 residues. Some of these peptides were used for the in silico prediction of their binding modes with DPPIV. Docking models showed that the possible mechanism of globulin peptides to inhibit DPPIV was through blocking the active dimer formation. Peptides were also found inside the major cavity where the natural substrates reach the catalytic site of the enzyme. This is the first report of the identification of inhibitory DPPIV peptides from amaranth hydrolysates and the prediction of their binding modes at the molecular level, leading to their possible use as functional food ingredients in the prevention of diabetes.
authors.affiliation: IPICyT, Instituto Potosino de Investigación Científica y Tecnológica A.C., San Luis Potosí, Mexico.
authors.forename: Aída J
authors.initials: AJ
authors.lastname: Velarde-Salcedo
authors.forename: Alberto
authors.initials: A
authors.lastname: Barrera-Pacheco
authors.forename: Samuel
authors.initials: S
authors.lastname: Lara-González
authors.forename: Gabriela M
authors.initials: GM
authors.lastname: Montero-Morán
authors.forename: Agustín
authors.initials: A
authors.lastname: Díaz-Gois
authors.forename: Elvira
authors.initials: E
authors.lastname: González de Mejia
authors.forename: Ana P
authors.initials: AP
authors.lastname: Barba de la Rosa
mesh_terms: D027721:Amaranthus / Q000737:chemistry* / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D020134:Catalytic Domain; D004063:Digestion; D018819:Dipeptidyl Peptidase 4 / Q000737:chemistry; D054873:Dipeptidyl-Peptidase IV Inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D006801:Humans; D006868:Hydrolysis; D008954:Models, Biological; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics; D012639:Seeds / Q000737:chemistry; D013552:Swine
chemical_list: D054873:Dipeptidyl-Peptidase IV Inhibitors; D010455:Peptides; D010940:Plant Proteins; D018819:Dipeptidyl Peptidase 4