title: Effect of simulated gastrointestinal digestion on the antihypertensive properties of synthetic beta-lactoglobulin peptide sequences.
abstract: In this study, the antihypertensive activity in spontaneously hypertensive rats of two peptides isolated from beta-lactoglobulin hydrolysates with thermolysin was evaluated. These peptides, with sequences LLF [beta-lg f(103-105)] and LQKW [beta-lg f(58-61)], showed potent in vitro ACE-inhibitory activity. Two hours after administration, both sequences caused a clear and significant decrease in the blood pressure of these rats. The impact of a simulated gastrointestinal digestion on ACE-inhibitory and antihypertensive activities of these peptides was also studied. The results showed that both fragments were susceptible to proteolytic degradation after incubation with pepsin and Corolase PP. In addition, their in vitro ACE-inhibitory activity decreased after the simulated digestion. It is likely that fragment LQK was the active end product of the gastrointestinal digestion of peptide LQKW. The fragment LL, observed after digestion of peptide LLF, probably exert its antihypertensive effect through a mechanism of action different than ACE-inhibition.
authors.affiliation: Instituto de Fermentaciones Industriales (CSIC). Madrid. Spain.
authors.forename: Blanca
authors.initials: B
authors.lastname: Hernández-Ledesma
authors.forename: Marta
authors.initials: M
authors.lastname: Miguel
authors.forename: Lourdes
authors.initials: L
authors.lastname: Amigo
authors.forename: Maria Amaya
authors.initials: MA
authors.lastname: Aleixandre
authors.forename: Isidra
authors.initials: I
authors.lastname: Recio
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D004063:Digestion / Q000502:physiology*; D041981:Gastrointestinal Tract / Q000378:metabolism*; D007782:Lactoglobulins / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D007782:Lactoglobulins; D010455:Peptides