JP3403794B2 - Antihypertensive and hypotensive functional food - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to angiotensin II.
The present invention relates to an antihypertensive agent and an antihypertensive functional food containing a peptide having the sequence of a fragment of the above (1) as an active ingredient.

[0002]

2. Description of the Related Art Angiotensinogen, which is a renin substrate synthesized in the liver and various tissues, is cleaved by the renin enzyme existing in the kidney and other tissues to produce angiotensin I in the blood and various tissues. . This angiotensin I shows almost no antihypertensive action, but by the action of angiotensin I converting enzyme (hereinafter abbreviated as ACE), the dipeptide histidyl leucine is released from the carboxyl terminus and converted to angiotensin II, which has a strong pressor action. cause. In addition, ACE has been confirmed to be the same substance as kininase II that catalyzes the decomposition of the blood pressure-lowering substance, prazikinin, and an inhibitor of this enzyme exhibits a blood pressure-lowering action, and also improves arteriosclerosis and heart disease. Is known to have the effect of 1977 Ondett
i et al. synthesized captopril as an orally administrable ACE inhibitor, and then it was revealed to be useful as a therapeutic drug for hypertension. At present, many inhibitory peptides are recognized from the enzymatic hydrolysates of food proteins, but in fact, few of them have been proved to be effective.

[0003]

Angiotensin I is slightly different depending on its origin as shown in Table 1 below.
It can be said that the 4th place is very similar, as it is a perfect match.

[0004]

[Table 1]

Angiotensin I is an angiotensin II, Asp-Arg-Val, which is decomposed by ACE.
-Tyr-Ile-His-Pro-Phe,
This raises blood pressure. However, angiotensin II was released from the N-terminal Asp by plasma aminopeptidase, and angiotensin III and Arg-Val-T were released.
yr-Ile-His-Pro-Phe. The fact that angiotensin III has an ACE inhibitory effect was revealed by BIE-SHUNG et al. In 1977. Furthermore, it is considered that angiopeptidase releases an N-terminal Arg from an aminopeptidase to produce an inactive hexapeptide. However, there is no mention of the functionality of the fragments produced by subsequent degradation. In the present invention, a peptide having a sequence of a fragment of angiotensin II degradation fragment is supposed and it is to confirm whether or not they have a hypotensive action.

[0006]

DISCLOSURE OF THE INVENTION In the present invention, a peptide having the sequence of a fragment of a fragment of angiotensin II, that is, Asp-Arg-Val-Tyr-Ile.
-His-Pro, Arg-Var-Tyr, Val-
Tyr-Ile, Arg-Val, Val-Tyr, T
yr-Ile, Ile-His, His-Pro, Pr
Assuming o-Phe, each peptide is prepared as a single product, the IC ₅₀ value of ACE inhibitory activity is measured in each, and the effect is confirmed, and the antihypertensive agent or antihypertensive functional food of the present invention is prepared. It came to completion.

The present invention provides a peptide having the sequence of a fragment of a fragment of angiotensin II, namely Asp-A.
rg-Val-Tyr-Ile-His-Pro, Ar
g-Var-Tyr, Val-Tyr-Ile, Arg
-Val, Val-Tyr, Tyr-Ile, Ile-
The present invention relates to an antihypertensive agent or an antihypertensive functional food containing one or more selected from His, His-Pro and Pro-Phe.

The present invention also provides a peptide, Asp-Ar.
g-Val-Tyr-Ile-His-Pro, Arg
-Var-Tyr, Val-Tyr-Ile, Val-
The present invention relates to an antihypertensive agent or an antihypertensive functional food containing one or more selected from Tyr and Ile-His as an active ingredient.

[0009] The inhibitory activity against ACE of a fragment of angiotensin (which does not include angiotensin III), which has never been known, is surprising, and Val
IC _{50 of} inhibition of ACE activity of Tyr (valyl tyrosine)
The value (μM) is very good, and Val-
Since Tyr is present in the blood, Val
-Tyr and the like are considered to be excellent antihypertensive agents.

Each peptide of the present invention is one kind or two kinds.
Depending on the species, it can be used as an ACE inhibitor, for example, as a blood pressure lowering agent or a peptide for food for specified health use for the purpose of lowering blood pressure. Therefore, the present peptide is used as a food such as a seasoning and a food for nutritional enrichment, or as an additive for animal feed, and because of the above-mentioned unique physiological activity, it can be used as a medicine for the prevention or treatment of hypertensive diseases. As or as infusions, health foods,
It can be widely used as a clinical nutrition food.

When used as a food, the peptide may be added as it is, or may be used in combination with other foods or food components according to a conventional method. When used as a medicine, it can be administered orally or parenterally. In the case of oral administration, for example, tablets, granules, powders, capsules and powders can be prepared according to a conventional method, and in the case of parenteral administration, for example, injection preparations, drops, suppositories, etc. It can be used as an agent or the like.

Next, an embodiment of the present invention will be described. AC
E inhibitory activity was measured as follows. ACE (manufactured by Sigma (EC 3.4.15.1; derived from rabbit lung)) 2.5 m
U, Protein Research Institute synthetic substrate Hippuryl-L-hi
The method of Matsui et al. (T. Matsui, H. Matsu) using 12.5 mM of stidyl-L-leucine.
fuji and Y. Osajima: Biosc
i, Biotech. Biochem. , 56,517
(1992)). That is, the produced L-histidy-L-leucine was converted into TNP, and the absorbance at 416 nm was measured. The absorbance in the test solution is Eb, the value when water is added instead of the test solution is Ec, and the value in the test solution when the reaction stop solution is added in advance and the reaction is E
b _2, the value of water as Eb _1, inhibition rate (%) = (Ec-
Eb ₁ )-(Eb-Eb ₂ ) / (Ec-Eb ₁ ) × 100
Expressed as The ACE inhibitory activity IC ₅₀ value of the sample was represented by the protein concentration of the sample required to inhibit the ACE enzyme activity by 50% (inhibition rate). The angiotensin II fragment peptide was synthesized by the F-moc solid phase method.
The synthetic peptide was TSK gel ODS- in a linear gradient of 10% to 50% (40 minutes) acetonitrile.
Purity tests were performed using a 120T (10 μm) column.

[0013]

【Example】

Example 1 The angiotensin II fragment peptides shown in Table 2 were synthesized by the F-moc solid phase method, and the IC ₅₀ value (μM) of each peptide was determined. The results are shown in Table 2.

[0015]

[Table 2]

ANGIII, ANG (1-7) and A
Dipeptide Val-T in the sequence of rg-Val-Tyr
High ACE inhibitory activity was observed in yr. Generation of angiotensin II fragment in vivo was confirmed by the following experiment.

Example 2 Human plasma was used to decompose angiotensin II, and its behavior was shown by fractionation of angiotensin II fragments by HPLC.
That is, after preparing samples (human plasma only, human plasma + angiotensin II (direct reaction solution, 0 hours), human plasma + angiotensin II (3 hours after reaction), TSK gel O
Fractionation by reverse phase HPLC using a DS-120T column was performed. Elution was performed with a linear gradient of acetonitrile concentration in 0.1% trifluoroacetic acid of 5% to 50% (90 minutes), and 50 μl of each sample was injected. The results are as shown in FIG. 1, but it can be seen that Val-Tyr is confirmed in the central part.

Example 3 With respect to the blood pressure lowering action of the angiotensins shown in Table 3, an animal experiment was conducted using rats based on the following matters. (1) Animal SHR / nCrj male rat (SPF, 11 weeks old, 2
About 90 g), 30 animals are purchased, and after 1 week of quarantine and acclimatization, 20 animals are selected by selecting animals showing a tail artery pressure of 180 mmHg or more. (2) Specimen (Angiotensin) (1) AngIII (2-8), (2) Ang (3-
4) (Val-Tyr), (3) Captopril (3) group composition Group 1, negative control (no AngI) group, Group 11, sample (1) 20 mg / kg, (2) 20, 50 mg / kg There are a total of 4 groups for administration, and 5 animals per group. (4) Administration method The specimen is dissolved in physiological saline and administered into the femoral vein. Each volume is 1 ml. (5) Actual artillery method For animals, the arterial pressure of the tail is measured non-invasively in advance using a plethysmo, and 180 mmHg or more is randomly tested. Nembutal (50mg / kg, ip) anesthesia, a polyethylene tube was inserted indwelled in cervical artery, connects the disposer pull blood pressure transducer to record blood pressure waveform via a blood pressure amplifier. Analyte is administered via the cannula indwelled in thigh vein. (6) Analysis method Based on the obtained blood pressure curve, at an appropriate time point (4 times in total at the time of preliminary operation, sample administration, blood pressure decrease, and blood pressure recovery), the measured value and the necessary increase rate are F -T-test or Dunnet's multiple comparison method is used to perform a significant difference test and comparison between groups. The results are shown in Table 3.

[0019]

[Table 3]

As is clear from Table 3, Val-Tyr
Was found to have an excellent blood pressure lowering effect.

[Brief description of drawings]

FIG. 1 is a diagram obtained by fractionating an angiotensin II degradation product in Example 2 by reverse phase HPLC.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Eiji Seki, Eiji Seki, No. 779 Noda, Hirano-cho, Ozu-shi, Ehime 2 Inside Senmia Extract Co., Ltd. (56) Reference JP-A-3-133391 (JP, A) JP-A 6-166697 (JP, A) JP-A-6-256387 (JP, A) Am. J. Physiol. , 1989, Vol. 257, p. H324-H329 (58) Fields surveyed (Int.Cl. ⁷ , DB name) A61K 38/00-38/58 CA (STN) MEDLINE (STN) BIOSIS (STN)

Claims (2)

(57) [Claims] 1. The following peptide: Val-Tyr-Ile, Ile-His, An antihypertensive agent containing 1 or 2 selected from 2. A hypotensive functional food containing 1 or 2 selected from the following peptides: Val-Tyr-Ile and Ile-His.