title: Antihypertensive effect of casein hydrolysate in a placebo-controlled study in subjects with high-normal blood pressure and mild hypertension.
abstract: We describe a clinical trial to study the efficacy of a casein hydrolysate, prepared using an Aspergillus oryzae protease, containing the major angiotensin-I-converting enzyme inhibitory peptides Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP) in a single-blind, placebo-controlled study. A total of 131 volunteers with high-normal blood pressure and mild hypertension were randomly divided into four groups (n 32 or 33 in each group). Each volunteer was given two tablets containing four different dosages of VPP and IPP (VPP+IPP: 0, 1.8, 2.5 and 3.6 mg), daily for 6 weeks. A significant decrease in systolic blood pressure was observed at 6 weeks in the active group receiving 1.8 mg (P<0.01) VPP and IPP; in the active groups receiving either 2.5 mg or 3.6 mg, systolic blood pressure was decreased at both 3 weeks (P<0.05 and P<0.05) and 6 weeks (P<0.001 and P<0.0001) compared with systolic blood pressure measured before treatment. Changes in the systolic blood pressure after 6 weeks of treatment in the four groups were --1.7, --6.3, --6.7 and --10.1 mmHg, and these effects were dose dependent. In addition, a significant difference in systolic blood pressure between the placebo group and the VPP and IPP group receiving 3.6 mg was observed (P<0.001) by two-way ANOVA. The antihypertensive effect was greater in mildly hypertensive subjects (n 20 or 21 in each group) than in any of the other subjects. No significant change of diastolic blood pressure was observed for all the test groups, and no differences in diastolic blood pressure in the test sample groups compared with the placebo group were observed during the test period.
authors.affiliation: Food Research Laboratory, Calpis Co. Ltd. Sagamihara, Kanagawa, Japan.
authors.forename: Seiichi
authors.initials: S
authors.lastname: Mizuno
authors.forename: Keiichi
authors.initials: K
authors.lastname: Matsuura
authors.forename: Takanobu
authors.initials: T
authors.lastname: Gotou
authors.forename: Shingo
authors.initials: S
authors.lastname: Nishimura
authors.forename: Osami
authors.initials: O
authors.lastname: Kajimoto
authors.forename: Mitsuharu
authors.initials: M
authors.lastname: Yabune
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Kajimoto
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Yamamoto
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000704:Analysis of Variance; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D001236:Aspergillus oryzae; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D002364:Caseins / Q000008:administration & dosage / Q000737:chemistry; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D006973:Hypertension / Q000178:diet therapy* / Q000503:physiopathology; D008297:Male; D009842:Oligopeptides / Q000008:administration & dosage*; D016037:Single-Blind Method
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D002364:Caseins; D009842:Oligopeptides; C489032:isoleucyl-prolyl-proline; C489031:valyl-prolyl-proline; C475729:casein hydrolysate