AmealPeptide® Clinical Evidence

American Journal of Clinical Nutrition 1996; 64:767–71.

Hata, Y., et al. A placebo-controlled study of the effect of sour milk on blood pressure in
hypertensive subjects.

Topic:
Does sour milk have an effect on hypertensive subjects?

Background:
Hypertension is a well-known risk factor for cardiovascular diseases. Dietary treatments as well asmedical treatments with pharmaceuticals are important to control the blood pressure of hypertensive subjects. Angiotensin converting enzyme (ACE) is a key enzyme in the reninangiotensin system that plays an important role in the regulation of blood pressure. Several studies suggest that sour milk containing
ACE-inhibitory tripeptides conveys an antihypertensive effect in rats. Therefore, food containing ACE-inhibitory tripeptides provides a promising dietary approach with an expected antihypertensive effect.

Study Type:
Human clinical intervention trial

Study Design:
Randomized, double-blind placebo-controlled design: Subjects received sour milk
containing ACE-inhibitory tripeptides (test), or acidified milk (placebo) daily for 8 weeks.

Subjects:
36 hypertensive subjects were tested. Although 32 of them were treated with antihypertensive
medicine, the doses and kind of medicine used did not change throughout the trial. Data of 6
subjects were excluded because they did not complete the study.

Dosage:
100 mL of sour milk containing 1.5 mg of valylprolyl- proline and 1.1 mg of
isoleucyl-prolyl-proline(test), or acidified milk (placebo), daily for 8 weeks.

Results:
Sour milk supplementation resulted in the following changes:After 4 to 8 weeks of treatment, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were significantly decreased for the sour-milk test group, while no effect was visible on the placebo group.

Four weeks after treatment ended, the significant decreases in SBP and DBP at the endpoint
of treatment were maintained in the sour-milk test group.

No marked changes were observed on pulse rate in any of the groups.

Conclusion:
“This study demonstrates the antihypertensive effect of daily ingestion of sour milk in hypertensive subjects, most of whom were taking antihypertensive medication. ACE-inhibitory tripeptides
therefore induce additive antihypertensive effects to these medications.”

American Journal of Hypertension

2004; 17(8): 701–706
Mizushima, S., et al. Randomized Controlled Trial of Sour Milk on Blood Pressure in
Borderline Hypertensive Men.

Topic:
Does sour milk containing two tripeptides (valylprolyl- proline ([VPP] and iso-leucyl-prolylproline [IPP])
have an effect on blood pressure of borderline hypertensive men?

Background:
Hypertension is a well-known risk factor for cardiovascular diseases, including heart disease and stroke. Lifestyle modification, including dietary habits, as well as medical treatments with pharmaceuticals are important to control the blood pressure (BP) of hypertensive subjects. Angiotensin converting enzyme (ACE), the key enzyme in the renin-angiotensin system, plays an important role in regulating blood pressure and constitutes a promising target for hypertension reduction. Daily supplementation with foods containing ACEinhibitory tripeptides constitutes a promising dietary approach with an expected antihypertensive effect.

Study Type:
Human clinical intervention trial

Study Design:
Randomized, double-blind, placebo-controlled design: Subjects were randomly allocated into two groups: sour milk drink group and placebo (acidified milk)-drink group, for 4 weeks.

Subjects:
46 borderline hypertensive men who were not on antihypertensive medications were included in this study.

Dosage:
Subjects daily received 1 bottle (160 g) of either sour milk drink containing 1.24 mg of VPP and 0.72 mg of IPP or artificially acidified milk drink (placebo) for 4 weeks.

Results:
Sour milk supplementation resulted in the following changes:
Systolic blood pressure (SBP) significantly decreased at 2 and 4 weeks.The decrease in systolic
and diastolic BPs in the sour milk group tended to be greater than that in the placebo group; however,
the differences in BP between the two groups during the 4 weeks were not significant.

Conclusion:
“This trial demonstrated the beneficial effect of sour milk on BP in borderline hypertensive men
who were not taking antihypertensive medication.”

British Journal of Nutrition

2005; 94:84–91
Mizuno, S., et al. Antihypertensive effect of casein hydrolysate in a placebo-controlled study in subjects with high-normal blood pressure and mild hypertension.

Topic:
Does casein hydrolysate, prepared using an Aspergillus oryzae protease, containing ACEinhibitory tripeptides Val-Pro-Pro (VPP) and Ile- Pro-Pro (IPP) have an effect on high-normal blood pressure and mildly hypertensive individuals?

Background:
Besides therapeutic strategy and dietary surveillance, many antihypertensive tripeptides isolated from various hydrolysates of food proteins have been found to reduce and prevent high blood pressure.

The first isolation of the tripeptides Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP) was performed using casein by the proteolysis of Lactobacillus helveticus through fermentation. Animal experimentation showed that these tripeptides have an ACE-inhibitory activity.

However, L. helveticus–fermented milk might not be the best way to produce VPP and IPP because the milk fermentation is limited.

Study Type:
Human clinical intervention trial

Study Design:
Randomized and single-blind placebo-controlled trial over a total period of 8 weeks: 2-week pretreatment period and a 6-week treatment period.During a period of 6 weeks, subjects in the placebo group (n=32), test sample group 1 (n=33), test sample group 2 (n=33), and test sample group 3 (n=33) ingested 2 tablets containing 0, 1.8, 2.5, or 3.6 mg of VPP and IPP, respectively, with every breakfast.

Measurements of blood pressure, pulse rate, body weight, and standing height, and a medical examination were performed at the Soiken Clinic in Osaka, Japan, on all subjects at 2 weeks before and at 0, 1, 3, and 6 weeks after the start of the experiment.

Subjects:
131 individuals:

  • 52 men and 79 women between 30 and 57 years
  • Not taking any medication containing antihypertensive agents
  • 48 individuals with high-normal blood pressure (systolic blood pressure [SBP] 120–139 mm Hg) and 83 with mild hypertension (SBP 140–159 mm Hg)

Dosage:
0, 1.8, 2.5, or 3.6 mg VPP and IPP, respectively, with every breakfast for 6 weeks.

Results:
Blood pressure response:

  • The A. oryzae peptide intake significantly reduced blood pressure for the mildly hypertensive subjects. However, there were no significant differences in SBP or diastolic blood pressure and pulse rate for the high-normal subjects compared with the starting value.
  • The reduction of blood pressure was proportional to the dose received by the group. In fact, the group that received more VPP and IPP during the treatment showed a larger blood pressure decrease.
  • Body weight, BMI, and haematological study:
  • No abnormal variations observed
  • Medical examination and questioning
  • No abnormal symptoms

Conclusion:
“For the first time, a dose-dependent experiment was performed with antihypertensive peptides with hypertensive subjects. This study shows that there is a significant decrease in SBP for all subjects with all dosages of VPP and IPP after 6 weeks of treatment.”“Compared with previous results, this study demonstrates that A. oryzae hydrolysate and L. helveticus–fermented milk have similar antihypertensive effects with almost the same dosage of the two peptides (VPP and IPP).”

Journal of New Remedies & Clinics

2002; 51(1): 61–69
Hirata, H., et al. Clinical Effects of New Sour Milk Drink on Mild or Moderate Hypertensive Subjects.

Topic:
Does Lactobacillus helveticus–fermented milk containing lactotripeptides (Val-Pro-Pro, Ile- Pro-Pro) have an effect on mildly or moderately hypertensive individuals not taking any antihypertensive drugs in a double-blind study?

Background:
Sour milk, manufactured using a starter culture predominantly composed of the lactic acid bacteria Lactobacillus helveticus, demonstrated lifeextending, antitumor, immunomodulating, fatigue recovery and stress reduction, learning/memory, and other effects. In 1995, animal experiments showed that sour milk also has an antihypertensive effect on hypertensive rats. Other experiments have shown that sour milk also decreased the blood pressure of hypertensive subjects already taking prescription antihypertensive medication.
The antihypertensive activity of the sour milk is due to the tripeptides VPP and IPP. In fact, they have been identified as angiotensin I–converting enzyme (ACE) inhibitors.
ACE is a circulating enzyme that participates in the body’s renin-angiotensin system (RAS), which mediates extracellular volume (i.e., that of the blood plasma, lymph, and interstitial fluid) and arterial vasoconstriction. The inhibition of ACE prevents high blood pressure.

Study Type:
Human clinical intervention trial

Study Design:
Double-blind, placebo-controlled trial: Subjects were divided into 2 groups. Each day at a fixed time,one received one bottle of the test milk and the other placebo over a total period of 8 weeks.Every 2 weeks, the subjects’ blood pressure and body weight were measured and a medical examination was conducted at the same time.Composition of bottle :
Test bottle: Sour milk was prepared by adding a starter culture containing L. helveticus and Saccharomyces cerevisiae to 9% (w/w) skim milk and fermented overnight.For the placebo control: artificially acidified milk was prepared by adding lactic acid to 9% (w/w) skim milk to achieve the same acidity as the sour milk test product.

Subjects:
32 mildly or moderately hypertensive subjects 15 men, 17 women, ages 50 ± 7.6 years with a systolic blood pressure (SBP) of 140–180 mm Hg and diastolic blood pressure (DBP) of 90–105 mm Hg.

Dosage:
1 bottle (120 g) of the test sample containing 2.66 mg of VPP and 1.60 mg of IPP.

Results:
The following results were reported for subjects supplemented with the new sour milk drinks when compared with the placebo group:Blood pressure and pulse rate:

  • During ingestion: SBP and DBP decreased significantly:
  • – Systolic blood pressure, which was 158.0 ± 9.0 mm Hg immediately before ingestion, decreased significantly by 11.7 ± 10.7 mm Hg after 4 weeks.
  • – Diastolic blood pressure was 92.6 ± 10.4 mm Hg, and it subsequently decreased to 84.4 ± 6.3 mm Hg (paired t-test: p < 0.01) at completion of the ingestion study period at 8 weeks. (For diastolic blood pressure, the antihypertensive effect was greater in the sour milk group than in the placebo group at 2 weeks after consumption.)
  • After the ingestion period, SBP and DBP returned to initial values.
  • Pulse rate showed no changes after the ingestion of the test drink.
  • Body weight, height, and BMI:
  • BMI: no significant changes
  • Serum biochemistry and urinalysis:
  • Hematology: no significant differences observed before and after ingestion between the 2 groups
  • Urinalysis: no abnormal variations observed in glucose, protein, urobilinogen, or occult blood values
  • Medical examination and questioning:
  • No abnormal symptoms (dry coughing, gastrointestinal symptoms, and skin symptoms thought to be attributable to the test drink)

Conclusion:
“If ingested continuously, sour milk from Lactobacillus helveticus is a safe way to reduce blood pressure of mildly or moderately hypertensive individuals not taking any antihypertensive drugs.”

Journal of Nutritional Food 2001;

4(3): 51–61
Kajimoto, O., et al. Hypotensive effects of tablets containing “lactotripeptides (VPP, IPP).”

Topic:
Does a daily intake of tablets containing lactotripeptides (Val-Pro-Pro, Ile-Pro-Pro) have an effect on untreated hypertensive individuals?

Background:
Previous experiment has shown that milk fermented with Lactobacillus helveticus reduced and prevented high blood pressure. The ingredient involved in this phenomenon consists of the lactotripeptides Val- Pro-Pro (VPP) and Ile-Pro-Pro (IPP).

Study Type:
Human clinical intervention trial. Approved by the Institutional Review Board of the Institute of General Medical Science.

Study Design:
Randomized, double-blind, placebo-controlled trial over a total period of 14 weeks: During a period of 8 weeks, subjects took 2 tablets once a day containing VPP and IPP (n=42) or a placebo (n=39).The subjects’ blood pressure and pulse rate were measured every 2 weeks. In addition, a blood examination and urinalysis were done before the intake of tablets and at the end of the experiment.

Subjects:
81 mildly or moderately hypertensive subjects: 59 men, 22 women, ages 45 ± 11 years with a systolic blood pressure (SBP) of 140–179 mm Hg and diastolic blood pressure (DBP) of 90–109 mm Hg.

Dosage:
Each tablet (2 g) contained 1.26 mg of VPP and 0.82 mg of IPP.

Results:
The following results were reported for subjects receiving tablets containing the lactotripeptides when compared with the placebo group:

  • Blood pressure and pulse rate:
  • During the ingestion: SBP and DBP decreased significantly
  • No changes regarding the pulse rate after ingestion of the tablets
  • BMI, hematology tests, and urinalysis:
  • BMI: no significant changes
  • Hematology: no significant differences
  • Urinalysis: no abnormal variations observed
  • Medical examination and questioning:
  • No abnormal symptoms (dry coughing, gastrointestinal symptoms, and skin symptoms thought to be attributable to the test drink)

Conclusion:
Like sour milk, tablets containing lactotripeptides VPP and IPP have an efficient antihypertensive action in untreated hypertensive subjects.

Journal of Japan Society of Nutrition and Food Science

2001; 54:347–354
Kajimoto, O., et al. Hypotensive Effects of Sour Milk in Subjects with Mild or Moderate Hypertension.

Topic:
Does an intake of sour milk manufactured with Lactobacillus helveticus have an effect on untreated hypertensive individuals?

Background:
Animal experimentation has shown that sour milk fermented by Lactobacillus helveticus decreases blood pressure in rats. The antihypertensive effect is due to the presence of tripeptides VPP and IPP, which have angiotensin I–converting enzyme inhibitory activity (ACE-inhibitory activity).Previous studies have shown that sour milk taken for 8 weeks concomitant with the use of antihypertensive drugs in hypertensive subjects significantly decreased blood pressure.Can sour milk be used to prevent hypertension or be taken before any treatment for hypertension?

Study Type:
Human clinical intervention trial.

Study Design:
Randomized, double-blind, placebo-controlled trial over a total period of 14 weeks: a pre-observational period of 2 weeks, an intake period of 8 weeks, and a post-observational period of 4 weeks. During a period of 8 weeks, subjects drank a liquid yogurt containing the lactotripeptides VPP and IPP (n=15) or a placebo (n=15). The composition of these two drinks was similar except for the presence of VPP and IPP tripeptides in the test drink. Medical examinations, blood pressure and pulse rate measurements were performed every 2 weeks in the pre-intake observation period, intake period, and post-intake observation period. In addition, blood examinations and urinalysis were done before the intake of drinks and on the day of intake.

Subjects:
30 mildly or moderately hypertensive subjects untreated with drugs: 12 men, 18 women, ages 52 ± 6 years with a systolic blood pressure (SBP) of 140–180 mm Hg and diastolic blood pressure (DBP) of 90–105 mm Hg.

Dosage:
1 bottle (160 g) of the test sample containing 2.53 mg of VPP and 1.52 mg of IPP every morning for 8 weeks.

Results:
Blood pressure and pulse rate:

  • The test group: SBP and DBP decreased significantly compared with the initial value after 8 weeks. In addition, SBP also decreased significantly compared with placebo group after 8 weeks.
  • The placebo group: no changes of the SBP and DBP
  • No significant differences observed in the pulse rate between groups
  • BMI, hematology tests, and urinalysis:
  • BMI: no significant changes
  • Hematology: no significant differences
  • Urinalysis: no abnormal variations observed in glucose, protein, urobilinogen, or occult blood values
  • Medical examination and questioning:
  • No abnormal symptoms (dry coughing, gastrointestinal symptoms, and skin symptoms thought to be attributable to the test drink)

Conclusion:
After 4 weeks of continuous intake, sour milk can have a safe antihypertensive effect on untreated subjects with mild or moderate hypertension.

Journal of Japanese Society of Clinical Nutrition

2001; 23(3): 26–31 Itakura, H., et al. The Effect of Sour Milk on Blood Pressure in Untreated Hypertensive and Normotensive Subjects.

Topic:
Does sour milk have an effect on blood pressure of hypertensive and normotensive subjects?

Background:
Hypertension is considered to be a risk factor of coronary arteriosclerosis. It is generally recognized that a decrease in blood pressure not only suppresses its incidence rate but also helps prevent cerebrovascular impairment. Recently, food materials with antihypertensive effect have been reported as a new nutritional therapeutic modality. Angiotensin converting enzyme (ACE) is a key enzyme in the renin-angiotensin system that plays an important role in the regulation of blood pressure. Several studies suggest that sour milk conveys an antihypertensive effect on rats. Therefore, food containing ACE-inhibitory peptides provides a promising dietary approach with an expected antihypertensive effect.

Study Type:
Human clinical intervention trial

Study Design:
Randomized, double-blind, placebo-controlled design: The subjects ingested daily either sour milk or artificially acidified milk as a placebo for 8 weeks.

Subjects:
18 subjects with hypertension, who were not taking antihypertensive medication, and 26 subjects with normotension participated in this study.

Dosage:
95 ml of sour milk containing 1.5 mg of tripeptide VPP and 1.1 mg of tripeptide IPP (test), or acidified milk (placebo), daily for 8 weeks.

Results:
Sour milk supplementation resulted in the following changes:

Conclusions :

  • The systolic blood pressure (SBP) decreased significantly in untreated hypertensive subjects, at 2, 4, and 8 weeks after the beginning of ingestion of the sour milk. This decrease in SBP in the sour milk group tended to be greater than in the placebo group.
  • The decreased blood pressure returned to initial value at 4 weeks after cessation of the ingestion of sour milk.
  • In normotensive subjects, both treatments did not affect any indices measured, including blood pressure, heart rate, and blood serum indices.
  • In both the sour milk and placebo groups, no marked changes were observed in other indices, including pulse rate and blood serum indices.

“These results suggest that ingestion of sour milk is effective in decreasing the blood pressure level of subjects with hypertension. Moreover, sour milk was shown to
have no effect on blood pressure and other indices in the individuals with normal blood pressure.”

Journal of the American College of Nutrition

2005; 24(4): 257–265 Aihara, K., et al. Effect of Powdered Fermented Milk with Lactobacillus helveticus on Subjects with High-Normal Blood Pressure or Mild Hypertension.

Topic:
Does powdered fermented milk with Lactobacillus helveticus have an effect on subjects with mild hertension?

Background:
Hypertension is a known risk factor for cardiovascular diseases, including heart disease and stroke. Angiotensin converting enzyme (ACE), the key enzyme in the renin-angiotensin system, plays an important role in regulating blood pressure and constitutes a promising target for hypertension. L. helveticus–fermented milk has been shown to convey an antihypertensive effect on rats. Therefore, food containing ACE-inhibitory peptides provides a promising dietary approach with an expected antihypertensive effect.

Study Type:
Human clinical intervention trial

Study Design:
Randomized, double-blind, placebo-controlled design: Subjects received test tablets containing powdered fermented milk with L. helveticus CM4 daily for 4 weeks or the same amount of placebo tablets for 4 weeks.

Subjects:
40 subjects with high-normal blood pressure and 40 subjects with mild hypertension.

Dosage:
6 test tablets (12 g) of L. helveticus CM4 (containing 8.3 mg of Val-Pro-Pro and 4.7 mg of Ile-Pro-Pro) or placebo, daily for 4 weeks.

Results:
L. helveticus CM4 supplementation resulted in the following changes:

Conclusion:
“Daily ingestion of the tablets containing powdered fermented milk with L. helveticus CM4 in subjects with high-normal blood pressure or mild hypertension reduces elevated blood pressure without any adverse effects.”

Journal of Nutritional Food

2002; 5(3): 55–66 Kajimoto, O., et al. Antihypertensive effects of liquid yogurts containing “lactotripeptides (VPP, IPP)” in mild hypertensive subjects.

Topic:
Does an intake of liquid yogurt containing lactotripeptides (Val-Pro-Pro, Ile-Pro-Pro)
have an effect on untreated hypertensive individuals?

Background:
Hypertension is the term used to describe high blood pressure. Because there are no symptoms, people can develop heart disease and kidney problems without knowing they have high blood pressure. To prevent this disease, individuals are urged to reduce sodium, lose weight, and moderate alcohol consumption.
Animal and human experiments have shown that sour milk fermented by Lactobacillus helveticus decreases blood pressure due to the presence of manufactured tripeptides Val-Pro-Pro (VPP) and Ile- Pro-Pro (IPP), which have angiotensin I–converting enzyme inhibitory activity (ACE-inhibitory activity).

Study Type:
Human clinical intervention trial. Approved by the Institutional Review Board of the Institute
of General Medical Science.

Study Design:
Prospective, randomized, double-blind, placebocontrolled trial over a total period of 14 weeks: During a period of 8 weeks, subjects drank a liquid yogurt containing VPP and IPP (n=31) or a placebo (n=33). Composition of these two drinks was similar except for the presence of VPP and IPP tripeptides in the test drink. Blood pressure and pulse rate were measured 10 times: 3 times before, 5 times during the intake period, and 2 times after ingestion of the drink. In addition, blood examinations and urinalysis were done before the intake of drinks and on the day of intake.

Subjects:
64 mildly hypertensive subjects: 33 men, 31 women, ages 50 ± 11 years with a systolic blood
pressure (SBP) of 140–159 mm Hg and diastolic blood pressure (DBP) of 90–99 mm Hg
(according to the 1999 World Health Organization/International Society of Hypertension definition).

Dosage:
1 bottle (150 g per bottle) of the supplementary drink (containing 1.12 mg of VPP and 0.79 mg of IPP) twice a day, after breakfast and dinner.

Results:
The following results were reported for subjects supplemented with drinks containing
VPP and IPP when compared with the placebo group:

Conclusion:
“Liquid yogurt containing lactotripeptides VPP and IPP has an antihypertensive action in
untreated hypertensive subjects.”

2011; 219:298–303 Nakamura, T., et al.

Casein hydrolysate containing Val-Pro-Pro and Ile-Pro-Pro improves central blood pressure and arterial stiffness in hypertensive subjects: A randomized, double-blind, placebocontrolled trial.

Topic:
Does casein hydrolysate have an effect on central blood pressure and arterial stiffness in hypertensive subjects?

Background:
Atherosclerosis is characterized by functional and/ or structural alterations of the vascular wall caused by hypertension, diabetes, and dyslipidemia. Its progression can lead to cardiovascular (CV) events. Research in several publications has demonstrated that the CV events could be predicted by the analysis of central blood pressure and arterial stiffness. These two parameters can be improved not only with pharmacological treatments but also by using the tripeptides valyl-prolyl-proline (VPP) and isoleucyl-prolyl-proline (IPP). In vitro, these two milk-derived peptides show inhibitory activities against angiotensin converting enzyme (ACE). Several clinical trials targeting stage-I hypertensive and prehypertensive subjects have shown that foods containing VPP and IPP decrease blood pressure. However, there is not enough evidence on the effectiveness of VPP and IPP compared with placebo on central blood pressure and arterial stiffness in hypertensive subjects.

Study Type:
Human clinical intervention trial

Study Design:

  • In both blood pressure groups, systolic blood pressure (SBP) and diastolic blood pressure (DBP) tended to decrease more in the test group than in the placebo group.
  • After 4 weeks of treatment of high-normal subjects, DBP but not SBP was lower in the test than in the placebo group.
  • In the mild-hypertension group, both SBP and DBP decreased in the test compared with the placebo group.
  • No marked changes were observed in other indices, including pulse rate, body weight, and blood serum variables, and no adverse effects attributed to the treatment were found in either group.
  • Blood pressure and pulse rate:
  • During ingestion: SBP and DBP decreased significantly
  • After the ingestion period: SBP and DBP returned to initial values
  • No changes regarding the pulse rate after the ingestion of the test drink
  • BMI, hematology tests, and urinalysis:
  • BMI: no significant changes
  • Hematology: no significant differences
  • Urinalysis: no abnormal variations observed in glucose, protein, urobilinogen, or occult blood values
  • Medical examination and questioning:
  • No abnormal symptoms (dry coughing, gastrointestinal symptoms, and skin symptoms thought to be attributable to the test drink)
  • Randomized, double blind, placebo-controlled study.
  • 70 Japanese subjects with hypertensive blood pressure (systolic blood pressure/diastolic blood pressure = 146.9/87.8 mm) were randomly allocated into two groups:
  • ◊ An active (test) group (n=35)
  • ◊ A placebo group (n=35)
  • The lifestyles of the subjects were the same except for the intake of the supplementary tablets.

Medical examination and measurement of hemodynamic parameters, including brachial blood pressure, were done 8 weeks before the trial.

Results
:
Subjects included in the study:

  • Ages 50–69
  • Hypertensive subjects who were not under antihypertensive medications
  • Systolic blood pressure (SBP) of 140–159 mm Hg
  • Subjects were excluded if they had:
  • SBP ≤ 135 mm Hg or ≥ 165 mm Hg or diastolic blood pressure (DBP) ≥ 100 mm Hg;
  • Any history of heart disease;
  • Any treatment for hypertension, dyslipidemia, or diabetes, use of dietary supplements influencing blood pressure;
  • Any history of a gastroenterological surgery;
  • Used any drugs a week before intervention (including hormone replacement therapy);
  • Any presence of milk or drug allergy;
  • Participated in other clinical research within three months of the first screening.

During 8 weeks, subjects received 4 tablets daily containing 1.5 mg of Val-Pro-Pro and 1.9 mg of Ile-Pro-Pro or placebo tablets prepared with sodium caseinate instead of casein hydrolysate.

Conclusion:
“This trial suggests that the food-derived peptides VPP and IPP improve peripheral vascular resistance, the compliance of large arteries, and prevent CV events.”

Japanese Pharmacology & Therapeutics

2007; 35(12): 1249–60 Ishida Y., et al. Antihypertensive Effects of the Tablet Containing “Lactotripeptide (VPP, IPP)” in Subjects with High Normal Blood Pressure or Mild Hypertension.

Topic:
Is consumption of tablets containing casein hydrolysate at the recommended daily dose efficient and safe for subjects with high-normal blood pressure or mild hypertension?

Background:
A normal blood pressure is defined as systolic blood pressure (SBP) < 130 mm Hg and diastolic blood pressure (DBP) < 85 mm Hg. Hypertension is a chronic condition in which the blood pressure is elevated, and it can be a major risk factor for stroke and other cardiovascular diseases. There are two types of hypertension: high-normal blood pressure (SBP 130–139 mm Hg or DBP 85–89 mm Hg) and mild hypertension (SBP 140–159 mm Hg or DBP 90–99 mm Hg). Lifestyle changes (food, exercise, smoking, etc.) can improve blood pressure level for hypertensive people.

Studies have suggested that the tripeptides Val- Pro-Pro (VPP) and Ile-Pro-Pro (IPP) from milk fermentation have an angiotensin converting enzyme inhibitory activity. Ingestion of sour milk in animals and humans has previously demonstrated a reduction of blood pressure.

In this study, the authors have developed a swallowable tablet containing casein hydrolysate.
What is the efficiency and the effect of the tablets on humans with mild
hypertension/high-normal blood pressure?

Study Type:
Human clinical intervention trial

Study Design:
Subjects:
Dosage:
Subjects received 4 tablets daily containing 1.28 mg of Val-Pro-Pro and 2.27 mg of Ile-Pro-Pro or placebo tablets containing sodium caseinate instead of casein hydrolysate for 12 weeks.

Conclusion:
“The systolic blood pressure in the test group was significantly reduced 2, 4, 8, 10, and 12 weeks after starting ingestion and 2 weeks after finishing ingestion compared with the placebo group. These results demonstrated the moderate antihypertensive effects and the safety of ‘lactotripeptide (VPP, IPP)’ tablets on high-normal to mild hypertensives.”

Journal of Medicinal Food

2005; 8(4): 423–430 Sano, J. et al. Effect of Casein Hydrolysate, Prepared with Protease Derived from Aspergillus oryzae, on Prehypertensive and Hypertensive Subjects.

Topic:
Does casein hydrolysate, prepared with Aspergillus oryzae protease, have an effect on blood pressure of hypertensive subjects?

Background:
The combination of medication and lifestyle changes (diet rich in fruit, vegetables, and low-fat dairy products, accompanied by a reduced intake of saturated and total fat) is currently used to reduce blood pressure.Angiotensin I converting enzyme (ACE) is important in the regulation of blood pressure because it catalyzes the formation of the potent vasopressor angiotensin II from angiotensin I. Inhibitors of ACE like the tripeptides Val-Pro-Pro and Ile-Pro-Pro have been isolated and identified from milk fermented with Lactobacillus helveticus. These peptides induce an antihypertensive effect in animal models and reduce blood pressure in subjects with elevated blood pressure.
In 2004, Mizuno et al. demonstrated that casein hydrolysate (Aspergillus oryzae hydrolysate) prepared using A. oryzae protease showed the highest ACE inhibitory activity among various enzymatic casein hydrolysates in animal models. Other data suggested also that A. oryzae hydrolysate could have an antihypertensive effect in mildly hypertensive humans.

Study Type:
Human clinical intervention trial

Study Design:
Randomized, double-blind, placebo-controlled study

  • After the 8-week intervention, SBP and DBP were significantly decreased from the base line for the active group; -10.5 mm Hg and -4.7 mm Hg, respectively.
  • There was a significant difference (95% confidence interval) in SBP reduction between the groups (-6.6 mm Hg for SBP for the active group).
  • The central SBP and DBP were reduced from base line, and the reduction in the active group was significantly greater than in the placebo group.
  • For arterial stiffness, baPWV (brachial-ankle pulse wave velocity) in the active group was reduced by 73.9 cm/s, with a reduction in brachial SBP of 10.5 mm Hg after the 8-week intervention with VPP and IPP.
  • No changes in the blood biochemistry or adverse events were observed between the groups.
  • Randomized, double-blind, placebo-controlled study
  • 111 subjects with high-normal blood pressure and mild hypertension were randomly allocated into two groups: ◊ A group taking test tablets containing casein hydrolysate with “lactotripeptide (VPP, IPP)” derived from milk protein ◊ A placebo group
  • The lifestyles of the subjects were the same except for the ingestion of the tablets.
  • Controls on the blood pressure of subjects were done 2 weeks before intake. Once this study was completed, the authors conducted a follow-up 2 weeks after the term of the study.
  • Subjects included in the study:
  • 68 men and 43 women, 50.8 ± 8.7 years old
  • Hypertensive subjects who were not taking antihypertensive medications
  • SBP of 130–159 mm Hg and/or DBP of 85–99 mm Hg, according to the 1999 definition of the World Health Organization/International Society of Hypertension
  • Subjects were excluded if they had:
  • Syndrome or anamnesis of cerebrovascular disorder;
  • A history of heart failure or myocardial infarction;
  • Renal/hepatic disorder;
  • Difficult-to-control diabetes mellitus;
  • Any allergy to cow’s milk; or
  • Were pregnant, lactating, or of childbearing potential.

Blood pressure and pulse rate:

  • 71 subjects had high-normal blood pressure (40 males and 31 females; SBP: 134.3 ± 3.0 mm Hg; DBP: 88.9 ± 6.8 mm Hg). At 10 weeks and 12 weeks from starting ingestion and at 2 weeks after finishing ingestion, SBP decreased significantly for the test group while there was no difference for the placebo group. DBP also decreased significantly for the test group while there was no difference for the placebo group at 2 weeks after finishing ingestion.
  • 40 subjects with mild hypertension (28 males and 12 females; SBP: 145.2 ± 5.0 mm Hg; DBP: 97.1 ± 8.5 mm Hg). There were significant differences in SBP between the two groups at 2, 8, 10, and 12 weeks after starting ingestion.
  • Body weight and body mass index (BMI):
  • BMI: no significant changes
  • Blood analysis:
  • No significant differences
  • Urinary analysis:
  • No significant difference between the two groups and no abnormal variations observed
  • Adverse events and findings in medical consultations:
  • No abnormal symptoms
  • 144 subjects with high-normal blood pressure (n=104) and mild hypertension (n=40) were randomly allocated into two groups:
  • ◊ A group drinking the test drink (200 ml/bottle) containing the A. oryzae hydrolysate every morning at the same time for 12 weeks.
  • ◊ A placebo group drinking a placebo drink at the same time for 12 weeks.
  • The lifestyles of the subjects were the same except for the supplementary drink.
  • Controls on the blood pressure of subjects were done 2 weeks before intake. Once this study was completed, the authors conducted a follow-up for 4 weeks.

Results:

  • Subjects included in the study:
  • 57 men and 87 women, ages 51 ± 10
  • Hypertensive subjects who were not on antihypertensive medications
  • SBP of 130–159 mm Hg and/or DBP of 85–99 mm Hg, according to the 1999 hypertension definition of the World Health Organization/International Society of Hypertension
  • Subjects were excluded if they had:
  • Any allergy to cow’s milk;
  • A history of heart failure or myocardial infarction;
  • An ongoing significant atrial fibrillation, irregular pulse;
  • A renal disease (serum creatinine 354 mol/L);
  • A hepatic disease, or anemia (serum hemoglobin 70 g/L); or
  • Were pregnant, lactating, or of childbearing potential
  • Subjects received daily 1 bottle of 200 ml containing 1.47 mg of Val-Pro-Pro and 1.60 mg of Ile-Pro-Pro or a placebo drink prepared with a concentrated mixture of vegetable and fruit juices, flavors, and water for 12 weeks.

Conclusion:
The casein hydrolysate, prepared with protease derived from A. oryzae, offers one such nonpharmacological approach, and we have shown here that it could provide an effective and novel means of preventing the development of hypertension.

  • After 4 weeks, the systolic blood pressure (SBP) and diastolic blood pressure (DBP) were significantly decreased for the test group while no effect was visible on the placebo group. Overall, blood pressure kept decreasing week after week in the test group.
  • In detail:
  • ◊ The statistics show significant differences between the 2 groups. Unlike the placebo group, high-normal blood pressure subjects show SBP and DBP decreased, respectively, for 6 weeks and 8 weeks after intake.
  • ◊ For mildly hypertensive subjects, only SBP showed a significant difference between the 2 groups.
  • No marked changes were observed on the pulse rate of either group.