title: Effect of Maillard reacted peptides on human salt taste and the amiloride-insensitive salt taste receptor (TRPV1t).
abstract: Maillard reacted peptides (MRPs) were synthesized by conjugating a peptide fraction (1000-5000 Da) purified from soy protein hydrolyzate with galacturonic acid, glucosamine, xylose, fructose, or glucose. The effect of MRPs was investigated on human salt taste and on the chorda tympani (CT) taste nerve responses to NaCl in Sprague-Dawley rats, wild-type, and transient receptor potential vanilloid 1 (TRPV1) knockout mice. MRPs produced a biphasic effect on human salt taste perception and on the CT responses in rats and wild-type mice in the presence of NaCl + benzamil (Bz, a blocker of epithelial Na+ channels), enhancing the NaCl response at low concentrations and suppressing it at high concentrations. The effectiveness of MRPs as salt taste enhancers varied with the conjugated sugar moiety: galacturonic acid = glucosamine > xylose > fructose > glucose. The concentrations at which MRPs enhanced human salt taste were significantly lower than the concentrations of MRPs that produced increase in the NaCl CT response. Elevated temperature, resiniferatoxin, capsaicin, and ethanol produced additive effects on the NaCl CT responses in the presence of MRPs. Elevated temperature and ethanol also enhanced human salt taste perception. N-(3-methoxyphenyl)-4-chlorocinnamid (a blocker of TRPV1t) inhibited the Bz-insensitive NaCl CT responses in the absence and presence of MRPs. TRPV1 knockout mice demonstrated no Bz-insensitive NaCl CT response in the absence or presence of MRPs. The results suggest that MRPs modulate human salt taste and the NaCl + Bz CT responses by interacting with TRPV1t.
authors.affiliation: Food Creation Center, Kyowa Hakko Food Specialties Co., Ltd, Ibaraki, Japan.
authors.forename: Tadayoshi
authors.initials: T
authors.lastname: Katsumata
authors.forename: Hiroko
authors.initials: H
authors.lastname: Nakakuki
authors.forename: Chikara
authors.initials: C
authors.lastname: Tokunaga
authors.forename: Noboru
authors.initials: N
authors.lastname: Fujii
authors.forename: Makoto
authors.initials: M
authors.lastname: Egi
authors.forename: Tam-Hao T
authors.initials: TH
authors.lastname: Phan
authors.forename: Shobha
authors.initials: S
authors.lastname: Mummalaneni
authors.forename: John A
authors.initials: JA
authors.lastname: DeSimone
authors.forename: Vijay
authors.initials: V
authors.lastname: Lyall
mesh_terms: D000465:Algorithms; D000584:Amiloride / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D002814:Chorda Tympani Nerve / Q000502:physiology*; D053503:Epithelial Sodium Channels / Q000187:drug effects / Q000502:physiology; D015416:Maillard Reaction; D051379:Mice; D018345:Mice, Knockout; D010455:Peptides / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D026941:Sodium Channel Blockers / Q000494:pharmacology; D012965:Sodium Chloride / Q000737:chemistry; D050916:TRPV Cation Channels / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D013649:Taste / Q000502:physiology*
chemical_list: D053503:Epithelial Sodium Channels; D010455:Peptides; D026941:Sodium Channel Blockers; D050916:TRPV Cation Channels; C493921:TRPV1 protein, mouse; C493922:Trpv1 protein, rat; C013407:benzamil; D012965:Sodium Chloride; D000584:Amiloride