Abstract
Pharmaceutical angiotensin-converting enzyme (ACE) inhibitors have been shown to reduce arterial stiffness; the possible effect of food-derived putative ACE inhibitory peptides on this degenerative process, however, has not been reported. In the present study, casein hydrolysate containing the lactotripeptides, Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP), which has been found to have an antihypertensive effect in a number of clinical studies, was investigated for its ability to improve hemodynamic parameters, including central systolic blood pressure (cSBP), in hypertensive subjects. Twelve hypertensive subjects who were not on prescribed medication were monitored for various hemodynamic parameters, including brachial blood pressure (peripheral blood pressure), cSBP, and augmentation index (AI), at the start and then after 3, 6, and 9 weeks of a daily treatment comprising four tablets containing VPP and IPP. Compared with basal levels, treatment with casein hydrolysate for 6 and/or 9 weeks showed a significant reduction in peripheral systolic and diastolic blood pressure, AI, and cSBP, but not in heart rate or pulse pressure. cSBP showed a reduction sooner and greater (-21.8 mm Hg) than did brachial systolic blood pressure (-16.4 mm Hg) during the 9-week treatment. Although small and not placebo-controlled, this study suggests that continuous intake of VPP and IPP might have the potential to improve arterial stiffness as well as cSBP and peripheral brachial blood pressure.
