JP2816664B2 - Anti-dementia agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to dementia typified by Alzheimer's dementia, Parkinson's disease, schizophrenia (deflowering disease), cerebellar degeneration, Wilson's disease, Down's syndrome,
Retinitis pigmentosa, Huntington's chorea, tardive dyskinesia, Trede syndrome, manic depression, and pharmaceuticals useful for the treatment and prevention of myasthenia gravis, more specifically,
Germacrene-B (hereinafter referred to as "AT-6") and Serina-4 (14), 7 (1
1) -Dien-8-one (Selina-4 (14),
7 (11) -dien-8-one, hereinafter "AT-9"
Nicotinic acetylcholine receptor (hereinafter referred to as “nAchRs”) enhancers containing sesquiterpenes as active ingredients.

[0002]

2. Description of the Related Art With the shift to an aging society, the number of patients with dementia is increasing, which has become a very serious social problem. There are many diseases that cause dementia, and they are roughly classified into dementia due to cerebral organic disorders and dementia due to physical illness due to stress. In particular, cerebrovascular dementia and Alzheimer's dementia are known as dementia due to cerebral organic disorders, which account for most of the causes, due to differences in the causes.

At present, it is said that symptoms of cerebral vascular dementia are slightly improved by using a combination of a cerebral blood flow improving agent and a cerebral metabolic activator.

However, since the cause of the onset of Alzheimer's dementia is still unknown, there is no appropriate pharmacotherapy or treatment method for inhibiting its onset and its progress.

For example, a method of replenishing choline, which is a raw material for acetylcholine biosynthesis, as described in JP-B-56-500374, JP-A-59-167514, JP-A-2-215351, and the like, and JP-A-2-67223, Kaihei 4-1
Although there is a method of increasing nerve growth factor (NGF) production as in 34028 and JP-A-7-25777, a remarkable effect cannot be expected because the action is indirect. Besides, T
Aminoacridine derivatives such as HA [Journal o
f Medical Chemistry, 31, 12
78 (1988); 32, 1805 (1989)] and physostigmine [Neurology, 8, 397].
(1978)] and a method for preventing a decrease in acetylcholine in the brain by inhibiting acetylcholinesterase as disclosed in JP-A-2-231421, JP-A-2-31422, JP-A-3-93728, and JP-A-4 −
112834, JP-A-4-198134, JP-A-6-1
Although there is a method of increasing the amount of acetylcholine by activating choline acetyltransferase (hereinafter referred to as "ChAT"), such as 28165, these methods can be expected to increase acetylcholine in the synaptic cleft. An increase in acetylcholine is dangerous because it may cause down-regulation of the receptor and decrease the receptor, leading to a decrease in the secondary signal transduction system. Some of these have side effects and others are not clinical and have not been put to practical use. Further, as described in JP-A-6-107544, M1
There is a method of activating the type muscarinic acetylcholine receptor, but this is not as dangerous as described above, but in Alzheimer's dementia, the reduction of nAchRs, which is an acetylcholine receptor, and M2 muscarinic acetylcholine receptor is remarkable, It has been reported that the M1 muscarinic acetylcholine receptor has few changes, and that reduction of nAchRs should be emphasized [Journal of Neuroch].
chemistry, 50, 1914 (1988)], and does not appear to be effective.

[0006] Therefore, there is a demand for the development of an anti-dementia agent, such as an nAchRs activator, acting on postsynaptic sites, particularly an anti-Alzheimer's dementia agent.

The conventionally known nAchRs activators are nicotine and acetylcholine alone. As described above, it is dangerous to increase acetylcholine excessively as described above, and nicotine causes tolerance, etc. Due to its toxicity, it is not suitable for use as a medicament. In addition, an nAchRs activating effect has been observed in the anti-dementia agent disclosed in JP-A-1-246224, and this anti-dementia agent was simultaneously disclosed in JP-A-2-31422.
It is disclosed that it activates AT, and since it also acts on presynaptic sites, its effect is not expected especially for Alzheimer-type dementia in which cholinergic cells are reduced. Not an agent.

In the case of an anti-dementia agent such as Japanese Patent Application Laid-Open No. 1-246224, a plant containing a crude drug component is administered by decoction or the like as it is, so that there are many impurities and the effect is so slow that it cannot exert a sufficient effect. There was a problem.

[0009]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide an anti-dementia agent, such as an nAchRs activator, which has no side effects and which has a high effect on only the postsynaptic site, particularly Alzheimer's. An object of the present invention is to provide a medicament effective for type dementia.

[0010]

[Means for Solving the Problems] In view of such circumstances, as a result of intensive studies, it has been found that AT-6 and AT-9 of sesquiterpenes have nAChRs without activating ChAT.
Remarkably increases, furthermore, improves the brain wave (slow wave observed in Alzheimer's dementia patients) of Alzheimer's dementia model rat (Basic ganglion destruction rat), and their nAchRs increasing effect is a known herbal medicine. It was found that the amount was smaller than that of the essential oil and was clearly twice or more, and the present invention was completed. That is, the present invention provides an anti-dementia agent comprising as an active ingredient any one of AT-6 and AT-9, which are sesquiterpenes, or a mixture of both compounds. is there.

The diseases targeted by the anti-dementia agent of the present invention include:
Diseases that are effective in increasing nAchRs containing sesquiterpenes as active ingredients, such as dementia typified by Alzheimer's dementia, Parkinson's disease, schizophrenia (dementia), cerebellar degeneration, Wilson's disease, and Down's syndrome , Retinitis pigmentosa, Huntington's chorea, tardive dyskinesia,
The present invention provides therapeutic and prophylactic agents for Tredde's syndrome, mania / depression, myasthenia gravis, and the like.

The sesquiterpenes which are the active ingredients of the present invention are a group of organic compounds having 15 carbon atoms and are generally known substances which are present in various plant essential oils and are described in the following documents. Yes (Encyclopedia of Science and Chemistry, Iwanami Shoten, 199
4 years revised version). Conventionally, these essential oils have only been used as fragrances, and even as sesquiterpenes, only an anthelmintic effect is known, and there is no report that they act on the central nervous system.

The sesquiterpenes as the active ingredient used in the anti-dementia agent of the present invention may be chemically synthesized sesquiterpenes, or a microorganism, plant or animal containing sesquiterpenes may be dried and ground. The extract may be an extract from microorganisms, plants or animals containing sesquiterpenes. Further, it may be purified from the powder or the extract. Further, they can be used in appropriate combination.

The extract containing the sesquiterpenes as the active ingredient of the present invention includes bodhi tree flower oil, neroli oil,
Bergamot oil, lemon oil, camphor oil, hop oil,
Extracts and extracts of crude drugs such as hashish oil, orthodone oil, clove oil, sandalwood oil, cedar oil, turpentine oil, mugwort seed oil, plant essential oils such as celery seed oil, blue jujube, white jujube, toki and river kyu Finally, there are various Chinese herbal medicines and the like containing various crude drugs as constituent herbs, but the present invention is not particularly limited thereto.

In order to purify sesquiterpenes from the above extract, methanol, ethanol, propanol, isopropanol, butanol, acetone, methyl ethyl ketone, benzene, chloroform, ethyl acetate,
Using an organic solvent such as ether, n-hexane, cyclohexane, petroleum ether, liquid-liquid extraction, silica gel,
Purification can be carried out by column chromatography using silica, activated alumina, or a synthetic resin such as Amberlite XAD as a filler, and further by high performance liquid chromatography, but is not particularly limited thereto.

[0016]

AT-6, a monocyclic sesquiterpene having a germacrene basic skeleton, which is an active ingredient of the present invention.

And a bicyclic sesquiterpene AT-9 having a serinane basic skeleton

The chemical structural formula of the formula is shown in a separate document.

[0018]

The sesquiterpenes of the present invention are substances which naturally exist widely in nature. Since plant essential oils containing these sesquiterpenes have been used as fragrances for a long time, they have low toxicity and high safety. Also, even if administered for a long period of time, there is almost no side effect and there is no habit like a hemp drug, so that it has a great significance as a drug.

The dosage of the drug of the present invention varies depending on the route of administration, the degree of the disease, and the age of the recipient. When the active ingredient is a pure substance of AT-6 or AT-9, it is generally administered by oral administration. , 0.001 to 100 mg per adult per day,
Preferably, the dose of 0.01 to 10 mg may be administered in 1 to 3 divided doses. The active ingredient is AT-6 or AT-9.
In the case of an extract such as an essential oil containing, it depends on the route of administration, the degree of the disease and the age of the recipient, but one adult
0.01 to 1000 mg per day, preferably 0.1 to
The 100 mg dose may be administered in 1 to 3 divided doses. In the case where the active ingredient is a crude drug extract powder containing AT-6 or AT-9 or a crude extract such as a herbal medicine, it depends on the route of administration, the degree of the disease, and the age of the recipient. 1
An amount of about 1 to 10 g per day may be administered in 1 to 3 divided doses.

The drug of the present invention can be formulated as the above pure substance or purified product as it is, or by combining an extract thereof with a known pharmaceutical carrier. The administration form is not particularly limited and is appropriately selected and used as needed, and according to the general rules of preparations, granules, capsules, tablets,
It can be administered by any of oral preparations such as fine granules and powders, and parenteral preparations such as injections, drops and suppositories.

Oral preparations are produced in the usual manner using, for example, starch, lactose, sucrose, mannitol, carboxymethylcellulose, corn starch, inorganic salts and the like. In this type of preparation, in addition to the above-mentioned excipients, a binder, a disintegrant, a surfactant, an activator, a fluidity promoter, a flavoring agent, a coloring agent, a flavor, and the like can be used as appropriate.

For example, binders that can be used as a raw material for the preparation of the present invention include starch, dextrin, gum arabic, gelatin, hydroxypropyl starch, methylcellulose, sodium carboxymethylcellulose, hydroxypropylcellulose, crystalline cellulose,
Examples include, but are not limited to, ethylcellulose, polyvinylpyrrolidone, and macrogol.

Examples of the disintegrant usable as a raw material for the preparation of the present invention include starch, hydroxypropyl starch, sodium carboxymethylcellulose, calcium carboxymethylcellulose, carboxymethylcellulose and low-substituted hydroxypropylcellulose.
It is not particularly limited to this.

Surfactants which can be used as a raw material for the preparation of the present invention include sodium lauryl sulfate, soybean lecithin, sucrose fatty acid ester, polosorbate 80 and the like, but are not particularly limited thereto.

The activating agent usable as a raw material for the preparation of the present invention includes talc, waxes, hydrogenated vegetable oils, sucrose fatty acid esters, magnesium stearate, aluminum stearate, calcium stearate, polyethylene glycol and the like. However, the present invention is not particularly limited to this.

The fluidity enhancer usable as a raw material for the preparation of the present invention includes, but is not limited to, light anhydrous silicic acid, dried aluminum hydroxide, synthetic magnesium silicate and the like.

On the other hand, the parenteral preparation of the present invention can be produced by a conventional method, and generally used as a diluent is distilled water for injection,
Physiological saline, aqueous glucose solution, vegetable oil for injection, sesame oil,
Peanut oil, soybean oil, corn oil, polyethylene glycol, propylene glycol and the like can be used.

Further, a bactericide, a preservative and a stabilizer may be added as required. Further, from the viewpoint of stability, this parenteral preparation can be frozen after filling into a vial or the like, water can be removed by a usual freezing technique, and the liquid preparation can be readjusted from the lyophilized product immediately before use. Further, if necessary, a tonicity agent,
Stabilizers, preservatives, soothing agents and the like may be added.

AT of monocyclic sesquiterpene having germacrene basic skeleton which is an active ingredient of the anti-dementia agent of the present invention
Examples of a method for producing AT-9 of a bicyclic sesquiterpene having a serinane basic skeleton, examples of preparations containing these active ingredients of the present invention, and comparative effect test examples are shown below. It is not limited to this. AT-6 and AT-9 of sesquiterpenes which are the main components of the anti-dementia agent of the present invention
May be a chemically synthesized product, and is not limited to those extracted from plants such as blue sap as shown below.

[0031]

Example 1 500 g of blue juice was cut into small pieces, and methanol 2
The mixture was extracted three times with L (2 l x 3) at room temperature. The extracts were combined and concentrated at 40 ° C under reduced pressure to obtain 49.3 g of a methanol extract.
This methanol extract was dissolved in 1 l of chloroform,
After removing the impurities, the chloroform layer was concentrated to obtain 26.3 g of a chloroform extract. Next, this chloroform extract was subjected to fractional elution with n-hexane containing 5% ethyl acetate (fraction 1) and n-hexane containing 20% ethyl acetate (fraction 2) by column chromatography packed with silica gel, By distilling off the solvent of each of the obtained fractions, 2.8 g of AT-6 fraction from Fraction 1 and 16 g of AT-9 fraction from Fraction 2 were obtained. These fractions are finally repeatedly subjected to high-performance liquid chromatography and further recrystallization, whereby 0.7 g of AT-6 bulk powder and 4.1 g of AT-protein, which are the main components of the anti-dementia agent of the present invention, are obtained. 9 bulk powders were obtained. The measurement results of the obtained AT-6 and AT-9 by thin-layer chromatography, infrared absorption spectrum, and nuclear magnetic resonance spectrum agreed with those of the standard. As shown below, these main components are also used as the main components of the drug substance of the present invention, but these main components can also be used as they are as the anti-dementia drug of the present invention.

[0032]

Example 2 Using the AT-6 bulk powder of the anti-dementia agent of the present invention obtained in Example 1, a solution of the anti-dementia agent of the present invention was prepared by a conventional method using the following formulation. . AT-6 bulk powder 3
00 mg, Nikkor HC-60 120 mg, Pepper tincture 0.05 ml, white sugar 5 g, ethanol 0.5
ml, methyl paraoxybenzoate 24 mg, and benzoic acid 2 mg were mixed well to obtain a homogeneous solution. This solution 30
ml was placed in an ampoule to obtain a solution.

[0033]

Example 3 A tablet of the anti-dementia agent of the present invention was prepared by the usual method using the AT-6 bulk powder of the anti-dementia agent of the present invention obtained in Example 1 according to the following formulation. . AT-6 bulk powder 3
00mg corn starch powder 10g, lactose powder 20g, carboxymethylcellulose calcium powder 1
0 g, 40 g of microcrystalline cellulose, 5 g of polyvinylpyrrolidone powder, and 10 g of talc powder were added, uniformly mixed, wet-granulated by a conventional method, and prepared into a tablet of the present invention using a tablet molding machine.

[0034]

Example 4 A tablet of the anti-dementia agent of the present invention was prepared by the usual method using the AT-9 bulk powder of the anti-dementia agent of the present invention obtained in Example 1 according to the following formulation. . To 100 g of AT-9 obtained in Example 1, 10 g of crystalline cellulose and 2 g of magnesium stearate were added, mixed well, and the mixture was tableted to prepare a tablet of 100 mg per tablet.

[0035]

EXAMPLE 5 0.01% by weight of AT-9 bulk powder obtained in Example 1 was dispersed in corn oil, 5% vegetable oil, and 70% gelatin.
0%, glycerin 22.9%, methyl paraoxybenzoate 0.15%, propyl paraoxybenzoate 0.51
% And water as appropriate, were manufactured by a conventional method to obtain 200 mg of soft capsules per tablet.

[0036]

[Comparative preparation 1] A comparative drug was produced by the following method. To a mixture of 6 g of Toki, 8 g of Soju and 6 g of Kawakyu, 200 ml of water was added, and the mixture was heated and extracted at 100 ° C. for 1 hour. The obtained extract was filtered, spray-dried, and spray-dried to 3.1 g. A powder was obtained. This was designated as Comparative Dust 1.

[0037]

[Effect test example 1] (nAchRs increasing effect) An anti-dementia agent of the present invention shown in the following table and the above comparative agent were administered to 22-day-old male SD rats.
Each dose was administered together with drinking water for 10 days. After administration, the brain was quickly removed and the forebrain cortex was removed using 5 mM HEP.
Homogenize with ES buffer, centrifuge at 20,000 g for 15 minutes at 4 ° C.
After homogenizing with 0 mM HEPES in the same manner, centrifugation was performed again. The pellet thus obtained was adjusted to 10 mg / wet weight with 20 mM HEPES to obtain a sample. 1 for that sample
The mixture was mixed with 0 nM 3H-nicotine, incubated at 37 ° C. for 15 minutes, filtered by suction with a Whatman GF / C filter soaked with 0.05% PEI to stop the reaction, and the amount of nchRs was measured. Quantitation is Low
Bovine serum albumin was used as a standard according to the method of ry et al.
As a result, as shown in the table below, the sesquiterpenes AT-6 and AT-9 are the most effective, and they are clearly more than twice the amount of nAch compared to known crude drugs.
It was found to have an Rs increasing effect.

増 加 Drug dosage nAchRs increase rate ───── ─────────────────────────────── Control group Drinking water only 0.3% Comparative drug 1 500mg / kg 15.7 % AT-6 bulk powder obtained in Example 1 3 mg / kg 51.9% AT-6 bulk powder obtained in Example 1 30 mg / kg 42.4% AT-9 bulk obtained in Example 1 Powder 3 mg / kg 34.3% AT-9 bulk powder obtained in Example 1 30 mg / kg 58.1% ─────────────

When the ChAT activating activity of the above-mentioned drugs was examined, Comparative Drug 1 showed the activity, but AT-6 and AT-9 of the present invention did not. Thus, the anti-dementia agent of the present invention comprises nAchRs
That the increasing effect is much higher than that of known crude drugs;
The absence of AT stimulating activity proved to be a much better anti-dementia agent than the crude drug of Comparative Drug 1.

[0040]

[Effect test example 2] (EEG improvement effect) A Wistar male rat was fixed to a stereotaxic apparatus under Nembutal anesthesia 4 to 5 days before the start of EEG measurement, and a stainless steel electrode for disrupting the basal ganglia of Meinert was used. According to the brain diagram of Paxinos & Watson, the left Meinert nucleus (A: 2.0, L: 3.
5, H: 6.5), and a screw electrode for measuring the electroencephalogram was attached to the ruptured ipsilateral frontal region, and the electroencephalogram before Meinert's basal ganglia was destroyed was measured. Then, a direct current (5 mA,
30 sec. The Alzheimer's dementia model rat was prepared by electrical destruction of the Meinert nucleus in (1). EEG measurements were performed 50 days a day for 7 days after destruction, recorded on a data recorder, and changes in EEG were observed with a frequency analyzer. As a result, the EEG of the cerebral cortex of the rat with a destruction of the basal ganglia of Meynert showed a wave with a period later than the first day after the destruction (called a slow wave or a delta wave, which is a brain wave commonly seen in Alzheimer's dementia patients). The wave speed increased and the fast wave decreased, and this state of the electroencephalogram continued for one week during the measurement period.

Example 1 In rats to which AT-6 bulk powder was orally administered at a dose of 30 mg / kg twice a day, the appearance of δ waves was small and brain waves almost normal were observed, and abnormal brain waves due to destruction of the basal ganglia. Improvement was observed. It should be noted that the site of destruction of the basal ganglia of Meinert was confirmed by extracting the brain after measuring the electroencephalogram.

(Acute toxicity test) Examples 1 to 4 of the present invention
An acute toxicity test by oral administration of an anti-dementia agent was performed using ddY male mice and Wistar male rats.

Neither AT-6 bulk powder nor AT-9 bulk powder of Example 1 gave a fatal case even at 2 g / kg (measurement limit).

From the above results, the anti-dementia agent of the present invention was
NAchRs without toxicity and without activating ChAT
Increased the EEG in the dementia such as Alzheimer's dementia, and was found to be effective in dementia.

[0043]

[Brief explanation of chemical formula]

The monocyclic sesquiterpene AT- having a germacrene basic skeleton, which is an active ingredient of the anti-dementia agent of the present invention, AT-
6, Chemical name: Germacrene-B (Germacrene-B)
-B) chemical structural formula

## STR2 ## AT-9, a bicyclic sesquiterpene having a serinane basic skeleton, which is an active ingredient of the anti-dementia agent of the present invention, chemical name: Serina-4 (14), 7 (11) -diene-8-
ON (Selina-4 (14), 7 (11) -die
n-8-one)

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) A61K 31/015 A61K 31/12 A61K 35/78 CA (STN) MEDLINE (STN)

Claims (1)

(57) [Claims] 1. A monocyclic sesquiterpene having a germacrene basic skeleton, AT-6, chemical name: germacrene-
B (Germacrene-B) and AT-9 which is a bicyclic sesquiterpene having a serinane basic skeleton;
Chemical name: Serina-4 (14), 7 (11) -diene-8
-ON (Selina-4 (14), 7 (11) -di
en-8-one) or an anti-dementia agent characterized by containing a mixture of both compounds as an active ingredient.