We report here the antihypertensive effect of wheat germ (WG) hydrolysate and its dominant peptide, Ile-Val-Tyr (IVY), with potent angiotensin I-converting enzyme (ACE) inhibitory activity. The toxicity test of AG50W fraction purified from the WG hydrolysate and IVY in tidy mice revealed that 1 week median lethal concentrations of AG fraction and IVY were less than 100 and 10 mg/kg, respectively. As a result of an intravenous administration test of both inhibitors in spontaneously hypertensive rat (SHR), the mean arterial blood pressure (MAP) significantly decreased with the dose; the MAP reduction of 10.3 and 19.2 mmHg was observed at a dose of 50 mg/kg of AG fraction and 5 mg/kg of IVY, respectively. In addition to this behavior, the MAP gradually decreased after the 5 mg/kg of IVY injection (time to give a maximum reduction; 8 min), and the reduction was held for 20 min. By using rat and human plasma, IVY was found to be metabolized by the action of aminopeptidase in plasma to form a subsequent ACE inhibitor, Val- Tyr (VY). Thus, the intake of IVY as a physiologically functional food would serve in the lowering of blood pressure (BP) by the combined depressor effect of itself and its metabolite after the absorption.
All Science Journal Classification (ASJC) codes
- Pharmaceutical Science