New antihypertensive peptides isolated from rapeseed

• Published in: Peptides (New York, N.Y. : 1980) N.Y. : 1980), 2003-06, Vol.24 (6), p.791-798
• Main Authors: Marczak, Ewa D, Usui, Hachiro, Fujita, Hiroyuki, Yang, Yanjun, Yokoo, Megumi, Lipkowski, Andrzej W, Yoshikawa, Masaaki
• Format: Article
• Language: English
• Subjects: Administration, Oral; Angiotensin-Converting Enzyme Inhibitors - isolation & purification; Angiotensin-converting enzyme inhibitory peptides; Animals; Antihypertensive Agents - administration & dosage; Antihypertensive Agents - isolation & purification; Antihypertensive Agents - pharmacology; Antihypertensive effect; Biological and medical sciences; Blood Pressure - drug effects; Brassica rapa - chemistry; Cattle; Dose-Response Relationship, Drug; Fundamental and applied biological sciences. Psychology; Inhibitory Concentration 50; Peptide Fragments - chemistry; Peptide Fragments - isolation & purification; Peptides - administration & dosage; Peptides - isolation & purification; Peptides - pharmacology; Protein digest; Rapeseed; Rats; Rats, Inbred SHR; Spontaneously hypertensive rat; Swine; Time Factors; Vertebrates: endocrinology
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/S0196-9781(03)00174-8

Four potent angiotensin converting enzyme (ACE) inhibitory peptides, IY, RIY, VW and VWIS, were isolated from subtilisin digest of rapeseed protein. Among them RIY and VWIS are new peptides with IC 50 28 and 30 μM, respectively. All isolated peptides lowered blood pressure of spontaneously hypertensive rats (SHR) following oral administration. The maximum effect in the case of RIY was observed 4 h after administration, while maximum effect of other peptides on blood pressure occurred 2 h after administration. Furthermore, the antihypertensive effect of RIY was observed even in old rats, in which ACE inhibitors become less effective, suggesting that a different mechanism other than ACE inhibition is also involved in lowering blood pressure by this peptide. Subtilisin digest of rapeseed protein also significantly lowered blood pressure of SHR after oral administration of a single dosage 0.15 g/kg, exerting maximum antihypertensive effect 4 h after administration. This digest appears promising as a functional food, which may be useful in the prevention and treatment of hypertension.