JPH0446124A - Antiulcer agent - Google Patents

Abstract

PURPOSE:To obtain an antiulcer agent, containing adenosine or a derivative thereof as an active ingredient, having antiulcer action substantially without any oral toxicity including an influence on enterobacteria. CONSTITUTION:An antiulcer agent containing adenosine or a derivative thereof, preferably a compound expressed by the formula [R is H, CH3 or benzyl; R2 is H, OH, Cl, SCH3 or SCH2CH(CH3)2; R3 is CH2CH2CH(NH2)COOH or H; R4 is H or Cl], e.g. methylthioadenosine (vitamin L2) or 5'-deoxy-5'- chloroadenosine as an active ingredient. The aforementioned compound as a composition for preventing and inhibiting various ulcers is added to a wide range of normal foods and drinks and suitably used in the form of the foods and drinks for inhibiting and preventing the ulcers. The dose thereof is normally about 0.001-40mg/kg body weight/day.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention The present invention relates to an anti-ulcer agent and an anti-ulcer food containing adenosine or a derivative thereof.

Currently, anti-ulcer drugs such as cimetidine and cetraxate hydrochloride, which are histamine H2 receptor antagonists, are widely used. Although these drugs have an excellent effect on suppressing gastric acid secretion, they cannot be said to be perfect in terms of side effects and administration methods.

In view of the above, the present inventors have conducted extensive research and found that the present invention has strong antibacterial activity against caries and scoliosis, and is virtually non-toxic orally effective, including its effect on intestinal bacteria. The present invention was arrived at based on this knowledge.

The anti-ulcer substance of the present invention, its physiological properties, modes of use, etc. will be described in detail below.

The active ingredient of the anti-ulcer substance of the present invention may be adenosine or its derivatives, and particularly preferred examples include compounds represented by the following chemical formula.

HOH [In the formula, R, NiH, -CH,, -CHy@, R.

Ni H, -OH, -CI, -5CH,, -3CH2
CH(CHs)2, R3: CH2CH2
CH(NH2)COOH,H,R4: H.

CI,] More specifically, vitamin L! (Methylthioadenosine (MTA), 5'-deoxy-5'-chloroadenosine, N-6-methyladenosine, N-6-benzyladenosine, 2-chloroadenosine, 5°-deoxyisobutylthioadenosine, adenosine, its stereoisomerism Subongo adenosine (adenosine-9β)
-D-arabinofuranoside) and the like can be exemplified as particularly useful. Further, S-adenosylmethionine can be exemplified as a substance that is easily decomposed into vitamin L and exhibits activity.

Physiological properties 1, anti-ulcer activity As shown in the experimental examples below, the anti-ulcer agent of the present invention suppresses gastric acid secretion and is extremely effective as an anti-ulcer agent.

2. Toxicity Oral LD5. is more than 1 g/kg body weight and is substantially non-toxic.

Mode of Use The anti-ulcer substance of the present invention can be suitably used as oral compositions for preventing and suppressing various ulcers, or in the form of ulcer-suppressing and preventive foods and drinks by being added to a wide variety of ordinary foods and drinks.
The amount used is usually about 0.001 to 4 hours+9/kg body weight/day.

Hereinafter, the present invention will be explained in more detail using experimental examples and the like.

Experimental Example 1 Experimental materials and methods (1) Animals used: WisLar with a double weight of 159-3889
After inoculating male rats (Sankyo Lab), they were preliminarily bred for at least one week before use.

(2) Preparation of test substance: MTA, which is a white powder extracted and purified from yeast, was suspended in distilled water or 0.2% CMC (carboxymethyl cellulose, Na salt), and suspended in 40 m 9.
The concentrations were prepared as follows: 10 mg, 3 mg/kg/5 m(l).

Method for producing gastric disorder and administration method for test substance 2131 ([) Aspirin ulcer in rat: 40 ml of MTA1
The mice were orally administered at a concentration of 1/hg, LOmg/kg, or 3mg/kg for 5 days (once/day). After the rats were fasted for 20 days, their abdomen was opened under ether anesthesia, the gastric pylorus was ligated, and MTA at any concentration was immediately administered into the duodenum. After suturing the abdomen and waking up, aspirin 150 mg/kg (pH 2,
0) was orally administered.

Then, 6 hours later, under ether anesthesia. Killed by axillary exsanguination and treated with 1% hormonal The stomach, in which marine fluid was injected, was removed.

Stomach disorders are measured by long axis x short axis under a stereomicroscope. Measure the diameter (Cmm”) and express the total number. Shitko.

(II) Rat ethanol ulcer: MTA40+IIg
/kg, IO+u/kg for 5 days (1
After administration (times/day), the subjects were fasted for 20 hours. Furthermore, after each concentration of MTA was orally administered, 1.5 m (l) of 99.5% ethanol was orally administered at 1 hour. After 1 hour, the animals were sacrificed by exsanguination in the axilla, and 1% formalin solution was injected. The stomach was removed. Stomach damage was measured by measuring the major axis under a stereomicroscope and expressed as the total number (+im).

(i) Rat water immersion restraint ulcer: MTA 40mg
/h9.10mg/Jzg for 3 days (
After oral administration (once/day), they were fasted for 20 hours. Then, each concentration of MTA was orally administered, and 45 minutes later, the rabbits were fixed in a homemade wire mesh cage.
Soaked in water for 6 hours at 23°C.

After that, the stomach was removed in the same manner as above, and the lesion was Expressed as the total number of harms (,,).

Statistical analysis Data are expressed as mean standard error (MeanthSE), and significant differences are determined by -test.

Results MTA on rat gastric ulcers caused by various factors
We investigated the disability suppression effect of

MTA 40+++g/kg, lomg/kg or 3mg/ks was orally administered for 5 to 3 days (once a day) before the day of ulcer creation, and further administered once on the day of ulcer creation,
We investigated its effects.

1. Effect of MTA on aspirin ulcers Aspirin is said to cause damage to the gastric wall by reducing blood flow in the gastric mucosa, damaging the mucosa, and suppressing cytoprotective prostaglandens. MTA Ha10+m9/
It was significantly inhibited at h9 and above (Tables 1 and 2).

2. Effect of MTA on ethanol ulcers Ethanol causes ulcers due to direct cell necrosis, destruction of blood vessels, and leftward movement of the stomach. MTA effectively suppressed the gastric damage caused by 40 mg/kg teethanol (Table 3).

3. Effect of MTA on stress ulcers Stress causes ulcers by shifting gastric motility and acid secretion to the left via hormones and nerves, and by impairing microcirculation. For gastric disorders caused by water immersion restraint stress, MTA 40vry/
It showed a suppressive effect on 1i1J (Table 4).

As described above, MTA was found to have a preventive effect against gastric ulcers. In addition, cases cured by chemotherapy such as cimetidine or cetraxate hydrochloride frequently relapse after the drug administration ends. A preventive effect against this can also be expected.

Table I Aspirin-induced gastric collapse in rats Effect of MTA on (After administering the test substance for 5 days, Causes stomach disorders Manufactured.

Table 2 Aspirin-induced gastric ulcer in rats Effect of MTA on (water) M.T.A. (lθmg/jig) 32.56±11.93* 57.1% (Front wheel material I: + outer rotation (0°2%CMC) M.T.A. (40+++g/kg) 17.0±8.8 pieces 84.4% (After administering the test substance for 5 days, Causes stomach disorders Manufactured.

(0.2% CMC) MTA (40+ng/kg) 36.6±6.6*N53.6% MTA (10mg/J21?) 86.0±6.6% (Test substance was administered for 3 days (After that, gastric disorder was created.) Experimental Example 2 Experimental materials and method (1) Two animals used (298-450 g)
Male sLar rats were used. After purchase (Santsutsu Lab), preliminarily bred for over a week before use.

(2) Preparation of test substances: MTA (5'-deoxy-5'-methylthioadenosine), which is a white powder extracted and purified from yeast, and adenosine (Wako Pure Chemical Industries, Ltd.) were used as test substances. Each test substance was suspended in 0.2% CMC (carboxymethylcellulose, Na salt), and 40TAg/k
g or 1 (Jmg/kg/5mQ).

(3) Method for producing gastric disorder and administration method of test substance (1) Gastric ulcer caused by aspirin in rats:
After fasting for an hour, the abdomen was opened under knee chill anesthesia, the gastric pylorus was ligated, and 40 mg/kg of MTA or adenosine was immediately administered into the duodenum. The abdomen was sutured, and upon awakening, aspirin 150 mg/72 g (p 82.0 of 0
．． (suspended in 2% CMC solution) was orally administered. Six hours later, the animals were sacrificed by exsanguination under the axilla under ether anesthesia, and the stomachs injected with 1% formalin were removed. Stomach disorders were measured by measuring the major axis x minor axis (mm2) under a stereoscopic microscope and expressed as the total number.

Gastric aS induced by ethanol in rats: After 40 mg/ky of MTA or adenosine was orally administered to rats fasted for 20 hours, 99.5% ethanol was orally administered at 1.5 m (2). After 1 hour, axillary exsanguination was performed. The animals were sacrificed using 1% formalin, and the stomach was removed by injecting 1% formalin.

The degree of gastric disorder can be determined by measuring the major axis. (i) It was expressed as the total number of (WIII+).

Gastric juice secretion in rats: Rats were fasted for 20 hours, opened under ether anesthesia, and the pylorus of the stomach was ligated. Immediately after injecting MTA into the duodenum at 40 mg/kg and 10 mg/9.
Alternatively, adenosine 40 mg/bg was administered. The abdomen was sutured, and 5 hours later, the gastric juice accumulated in the stomach was collected and its pH1 pepsin activity was examined. To measure pepsin activity, 0.1M Green-HCL buffer p H2.0 was used, 0.6%
Casein (dissolved in the same buffer) solution was used as a substrate. Add an equal amount of buffer to the collected gastric juice, and add 0.5 mR of the sample.
and 2.5 yaff of casein solution were mixed and heated at 37°C for 30
It was allowed to react for a minute. 7゜2% tric-Do acetic acid solution 2.5m&
was added, stirred, and allowed to stand for an additional 15 minutes. The absorbance of the filtrate was measured at a wavelength of 280 nm. - A chloroacetic acid solution was added to the mixture, stirred, a casein solution was added, and the absorbance of the filtrate was measured after standing for 15 minutes.

Then, from the absorbance of the sample to the absorbance of the control Amount of casein decomposed by subtracting the degree It was expressed as

Results Before creating gastric ulcers in rats, lO~40+xg/k
By orally administering 3-5 g of MTA or more, MTA
TA showed anti-ulcer effects. Therefore, the effects of single administration of MTA and adenosine were investigated.

1. Effect of MTA on gastric ulcer induced by aspirin or ethanol A single intraduodenal administration of MTA 4 (1 mg/kg) showed a clear inhibitory effect on the gastric disorder caused by aspirin administration.

Although adenosine showed an inhibitory tendency, no statistically significant inhibitory effect was observed (Back 5).

2.

On the other hand, MTA and adenosine effectively prevented the occurrence of gastric ulcers against ethanol 1-induced gastric disorder (Table 6).
.

Effects of MTA and adenosine on rat gastric juice secretion After the gastric pylorus was ligated and MTA was administered into the duodenum, the amount of gastric juice collected at 5 hours (per 10 h of rat body weight) was 9.10 I + 1 per 40 mg of MTA.
g/kg administration significantly decreased compared to the control group. Furthermore, although the gastric juice pH increased significantly with 10 mg/kg of MTA, no significant difference was observed after 9 doses of 40 mg/kg, so this may have occurred accidentally. No pepsin activity was observed (Table 7). Adenosine had no effect on gastric juice volume, gastric juice pH, or even activity (Table 8).

It is known that secretion of gastric juice is stimulated by acetylcholine, histamine, gastrin, and the like. MT
A suggests the possibility that it acts on any of these substances.

Conclusion MTA, when administered 4 to 6 times at a dose of 10 to 40 mg/kg or more, effectively suppresses ulcers caused by aspirin, ethanol, and water immersion restraint stress in rats.
Anti-ulcer effect was observed (Experiment Example 1). Even with the single administration of Experimental Example 2, the antiulcer effect on the aspirin ulcer and ethanol ulcer tested at 40 mg/kg was equivalent to or greater than that of multiple administrations of MTA. Therefore, it was considered that it has an anti-ulcer effect even in water immersion restraint stress ulcers.

Adenosine also seems to have an anti-ulcer effect, although it is weaker than MTA. MTA suppressed gastric juice secretion, but gastric juice p
H and pepsin activities were not affected. Adenosine had no effect on gastric secretion, pH, or pepsin activity.

Table 7: Effect of MTA on gastric juice secretion in rats (062%CM
C) Table 8 Effect of adenosine on rat gastric fluid partial pressure 40■,/
9 Experimental Example 3 Anti-ulcer activity of various adenosine derivatives The activity against gastric ulcers of six types of adenosine derivatives having the chemical formulas shown in Table 9 was measured in the same manner as in Experimental Example 2.

The results are shown in Table 10. The numbers in the table indicate the prevention of ulcers.
4 (%). Incidentally, these derivatives are commercially available from Sigma and others.

Table 9 Table 10 Experimental Example 4 Toxicity test ICR mouse (male 6 weeks old, average weight 31.0
9; 10 mice per group), the various adenosine derivatives were orally administered at 0.5 mQ of the physiological saline suspension at 1.10 and 100 m9/mouse per mouse, and 14
Observe whether the mice are alive or dead for several days.

L calculated according to Behrens-Karber
Ds.

The value Cmg/ht; i body weight) is 100(h++g/
kg body weight or more, and on the other hand, daily oral administration (10 (1 m
g/mouse) was completely non-toxic.

References 1) Ishihara-Ok, Haseyo Atsuko, Mokuyo Tatsuko, Yoneyama Atsuko, Kawai Yasuo, Kitamura Shigeru, Ishikawamae (1985) Inhibition of growth of dental caries and periodontal disease pathogens by intestinal lactic acid bacteria components Molar Health Journal 28 (3), 1044-10492) Toshio Kasama, Yu Fujii-1 Yoko Kaneko, Kiyoshi Mayuzumi (1986) 0xyb
Effects of utynin hydrochloride on gastric and duodenal ulcers and gastric acid secretion Applied Pharmacology 34 (4)
)713-719 3) Noriyoshi Kubo, Shunji Moriura, Takusei Makino, Hideaki Matsuda (198
9), Pharmacological activity of crude drugs and pit vipers (first report), Experimental effect of 50% ethanol extract on gastric ulcer Journal of Pharmacy 109 (8) 592-599

Claims (1)

[Claims] An anti-ulcer agent characterized by containing adenosine or its derivative as an active ingredient