title: Lactoferricin B-derived peptides with inhibitory effects on ECE-dependent vasoconstriction.
abstract: Endothelin-converting enzyme (ECE), a key peptidase in the endothelin (ET) system, cleaves inactive big ET-1 to produce active ET-1, which binds to ET(A) receptors to exert its vasoconstrictor and pressor effects. ECE inhibition could be beneficial in the treatment of hypertension. In this study, a set of eight lactoferricin B (LfcinB)-derived peptides, previously characterized in our laboratory as angiotensin-converting enzyme (ACE) inhibitory peptides, was examined for their inhibitory effects on ECE. In vitro inhibitory effects on ECE activity were assessed using both the synthetic fluorogenic peptide substrate V (FPS V) and the natural substrate big ET-1. To study vasoactive effects, an ex vivo functional assay was developed using isolated rabbit carotid artery segments. With FPS V, only four LfcinB-derived peptides induced inhibition of ECE activity, whereas the eight peptides showed ECE inhibitory effects with big ET-1 as substrate. Regarding the ex vivo assays, six LfcinB-derived peptides showed inhibition of big ET-1-induced, ECE-dependent vasoconstriction. A positive correlation between the inhibitory effects of LfcinB-derived peptides on ECE activity when using big ET-1 and the inhibitory effects on ECE-dependent vasoconstriction was shown. ECE-independent vasoconstriction induced by ET-1 was not affected, thus discarding effects of LfcinB-derived peptides on ET(A) receptors or intracellular signal transduction mechanisms. In conclusion, a combined in vitro and ex vivo method to assess the effects of potentially antihypertensive peptides on the ET system has been developed and applied to show the inhibitory effects on ECE-dependent vasoconstriction of six LfcinB-derived peptides, five of which were dual vasopeptidase (ACE/ECE) inhibitors.
authors.affiliation: Departamento de Biotecnología de Alimentos, Instituto de Agroquímica y Tecnología de Alimentos, Consejo Superior de Investigaciones Científicas, Burjassot, Valencia, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Fernández-Musoles
authors.forename: José Javier
authors.initials: JJ
authors.lastname: López-Díez
authors.forename: Germán
authors.initials: G
authors.lastname: Torregrosa
authors.forename: Salvador
authors.initials: S
authors.lastname: Vallés
authors.forename: Enrique
authors.initials: E
authors.lastname: Alborch
authors.forename: Paloma
authors.initials: P
authors.lastname: Manzanares
authors.forename: Juan B
authors.initials: JB
authors.lastname: Salom
mesh_terms: D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism / Q000494:pharmacology*; D019332:Endothelin-1 / Q000378:metabolism; D000072396:Endothelin-Converting Enzymes; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D007781:Lactoferrin / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D008666:Metalloendopeptidases / Q000378:metabolism / Q000494:pharmacology*; D010455:Peptides / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D011817:Rabbits; D044022:Receptor, Endothelin A / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D014661:Vasoconstriction / Q000187:drug effects* / Q000502:physiology
chemical_list: D019332:Endothelin-1; D010455:Peptides; D044022:Receptor, Endothelin A; C082171:lactoferricin B; D007781:Lactoferrin; D016282:Aspartic Acid Endopeptidases; D008666:Metalloendopeptidases; D000072396:Endothelin-Converting Enzymes