JPH01151514A - Treating and preventive agent for neuropathy - Google Patents

Abstract

PURPOSE:To obtain a treating and preventive agent for neuropathy caused by denaturation of neurocytes, containing a carboxylic acid or salt thereof as an active ingredient and capable of improving productivity of cells producing nervous growth factors. CONSTITUTION:The aimed substance obtained by using a carboxylic acid expressed by the formula or salt thereof alone or in a mixture with a normally used carrier. The above-mentioned substance is preferably used as intravenous injection or drops. In this case, 0.1-20wt.% carboxylic acid is blended as an active ingredient. The dose thereof is 0.6-60mg per day. Gallic acid and pyrogallol-4-carboxylic acid are exemplified as the carboxylic acid. For example, the substance is useful for treating and preventing Alzheimer's dementia, Huntington's chorea, etc.

Description

[Detailed description of the invention] [Industrial application field] TECHNICAL FIELD The present invention relates to agents for treating and preventing neurological diseases.

[Conventional technology]

Neurons play a major role in maintaining human mental activities such as intellectual functions, memory, emotions, and behavior. It is thought that neurotrophic factors specific to each neuron are required for the differentiation, survival, and functional expression of the neurons that form the basis of these mental activities, but this is still beyond speculation. Only,
The existence and function of nerve growth factor (hereinafter abbreviated as NGF) has been clarified. Since NGF is a neurotrophic factor for magnocellular cholinergic neurons in the basal forebrain, its relationship with Alzheimer's dementia has attracted attention [Pharmacia, Vol. 22, No. 2.1
47-151 (1986), Geriatric Psychiatry, Vol.
3, No. 6,751-758 (198G)).

Alzheimer's dementia is a disease that is accompanied by clinical symptoms such as dysphonia, focal symptoms, tonic constriction of the lower limbs, and epileptiform seizures, and has pathological findings such as senile plaques and Alzheimer's fibrillary tangles. It is a type of dementia. Although it has been on the rise in recent years in an aging society and is of great social concern, no method of improving or treating the symptoms has yet been found.

In the brains of patients with Alzheimer's disease, marked degeneration of the basal forebrain, centered on Meynert's basal ganglia, and a marked decrease in choline acetyltransferase (CAT) activity have been observed (Annu, Rev, Ncurosci, 3.77
(1980)), and in 1985, a study using rat brains revealed that NGF is a neurotrophic factor in this region of the brain (EMBOJ, 4.1389
(1985)), the relationship between NGF and this disease has attracted attention.

Furthermore, in the striatum of the brains of Huntington's chorea patients, GAB
Along with the loss of A-ergic neurons, the loss of cholinergic neurons is also significant, and it has been revealed that NGF also acts on endogenous cholinergic neurons in the striatum (Scientific
e, 234.1341 (1986)), this disease is caused by NGF.
It has been pointed out that there is a possibility that it is related to

Furthermore, the effects of NGF have been studied in animals such as rats, which can be used as models for various neurological diseases. It has been reported that the decrease in CAT activity can also be prevented (J, NeuroSc t,
, 6-12155 (1986), Brain R.
es, 293.305 (1985), 5cienc.
e, 235°214 (19B6), Proc, Nat
l, Acad, Sci, USA, 83.9231 (
1986)].

The present inventors demonstrated that NG in peripheral sympathetic innervation tissues and the brain.
It was demonstrated that F is biosynthesized, and that fibroblasts and astrodalia cells, which are interstitial cells in peripheral tissues and brain tissues, each play an important role in the biosynthesis of NGF (J, Biol. Cham, 259.1
259 (1984), Biochcm, Biop.
Hys, Res.

Commun, 136.57 (1986)).

In addition, we revealed that the antigenicity, molecular weight, isoelectric point, and biological activity of NGF produced by fibroblasts and astroglial cells are the same as submandibular gland NGF, which has been well studied. We found that when various neurotransmitters were added to the culture medium of L-M cells and astroglial cells, catecholamines (norepinephrine, epinephrine, and dopamine) exhibited the effect of promoting NGF synthesis (J
.

Biol, Chem, 201.6039 (1986
), Febs Lett, 208, 258 (198
6)).

The biggest problem in applying these in vitro results as a therapeutic drug is the development of a new technique to ensure that these NGF-inducing substances reach NGF-producing cells in the brain.

[Problem that the invention seeks to solve]

Thus, in these neurological diseases where the site where NGF acts as a neurotrophic factor degenerates, it is expected that NGF can be used as a therapeutic agent to stop the degeneration. In addition, once brain nerve cells undergo degeneration due to cerebrovascular disease, brain tumor, brain apex, head injury degenerative disease, anesthetic drug addiction, etc., there is no recovery throughout life, resulting in not only intellectual function decline and memory impairment, but also It causes various disorders such as emotional disorders and behavioral abnormalities, but nerve fibers have plasticity, and when damaged, healthy fibers in the vicinity will sprout, and new synapses will be formed to replace the damaged synapses. Therefore, it is expected that NGF can be used as a therapeutic agent to promote repair and regeneration of nerve function.

However, when trying to apply NGF to the treatment of various neurological diseases, NGF must reach the close vicinity of nerve cells that require NGF, and in the case of central nervous system diseases, NGF must be applied to the affected areas of brain cells. However, NGF cannot be delivered into the brain through the vascular system. This is because vascular endothelial cells in the brain are connected to each other by tight junctions (called the blood-brain barrier), and water and
This is because the transfer of substances other than gases and fat-soluble substances from the blood to the brain tissue is restricted, and proteins (including NGF), which are high molecular weight substances, cannot pass through the blood-brain barrier at all. be. Directly injecting NGF into the brain using a surgical method is too dangerous even with current technology.

[Means for solving problems]

The inventors of the present invention have conducted intensive research to solve the various problems mentioned above, and as a result, 1. We focused on finding a low-molecular compound that, when administered as an active ingredient into the blood, can reliably reach cells in the brain and activate astroglial cells in the brain that produce NGF, and as a result of various searches, we found: The present invention was completed based on the discovery that gallic acid, which is an analog of catechol, has a remarkable ability to induce NGF.

That is, the present invention is a neurological disease treatment/prevention agent containing a carboxylic acid represented by the formula or a non-toxic salt thereof as an active ingredient.

The carboxylic acid (1) used in the present invention is a compound known per se, and examples thereof include gallic acid and pyrogallol-4-carboxylic acid. Examples of the above-mentioned non-toxic salts include alkali metal salts such as sodium salts and potassium salts, alkaline earth metal salts such as calcium salts and magnesium salts, and salts with basic amino acids such as orthinine, arginine, and lysine. Other known salts are also included.

Carboxylic acid [1] or its non-toxic salt for the treatment of neurological diseases.
When used as a prophylactic agent, it is administered alone or in combination with a pharmaceutically acceptable drug. Its composition is determined by the route of administration, administration schedule, etc.

The dosage is determined depending on the patient's age, health condition, body weight, severity of symptoms, type of concurrent treatment, if any, frequency of treatment, nature of desired effect, etc.

The preferred dosage form is parenteral administration, such as intravenous injection or intravenous injection by drip.

Therapeutic doses are generally 0.6 to 60 mg/day for parenteral administration.

When administered parenterally, carboxylic acid [1] or a non-toxic salt thereof is used as a sterile solution with the addition of saline or other solutes such as glucose to make the solution isotonic.

Suitable vehicles for injection include sterile water, saline, dextrose, intravenous fluids, electrolyte solutions (for intravenous injection), and the like. These injection solutions usually contain 0.1 to 20% by weight of the active ingredient.

The active ingredient of the present invention has low toxicity compared to a pharmacologically effective dose and can be administered continuously. For example, the acute toxicity (tf! (LDSO)) by subcutaneous administration using mice is 90 mg
/kg.

The therapeutic and preventive agent for neurological diseases of the present invention improves the NGF-producing ability of NGF-producing cells, thereby treating neurological diseases caused by degeneration of nerve cells, such as Alzheimer's dementia,
It is useful for the treatment or prevention of Huntington's disease and the like.

〔Example〕

Next, the present invention will be specifically explained with reference to experiments and examples.

Attractive effect of NGF on L-M cells L-MiJ [l cells (fibroblasts) were treated with 0.5% peptone (
When maintaining the culture in 199 medium (manufactured by Flora) containing Gibco (manufactured by Gibco) and using it for testing, the cell density should be 2 to 4 x 10.
24-well culture dish (Falcon!! Rinimaki, cultured at 37℃ for about 3 days, and when it became confluent (approx. 10 cells/cm),
．． 199 containing 5% bovine serum albumin (manufactured by Amor)
0.5 ml of a solution containing the test product dissolved at a predetermined concentration was added to the medium. After 24 hours, the culture supernatant was collected and the NGF concentration was determined by enzyme immunoassay (S, Furukawa et al., J.).

Ncurochem,, ↓0,734 <1983)]
It was measured by The measured value is the NGF concentration in the culture supernatant (400-800 pg/me) not containing the test product.
It was calculated as a magnification of the average value of four measured values and the standard error r.

The results of measuring the increase in NGF content using gallic acid and pyrogallol-4-carboxylic acid as test products are shown in Figure 1. -) is used, 0.02
At a concentration of ~0.07mM, it exhibited a 5-6 times greater ability to induce NGF production than pyrogallol-4-carboxylic acid (--6-
-) showed about 4 times the ability to induce NGF production at a concentration of 0.04 mM.

Experimental Example 2 Induction effect of NGF on astroglial cells Astroglial cells were isolated from the whole brain of 8-day-old ICR mice.
hys, Ras, Commun,, 136. 57
(1986)), Dulbaacos' mod fed containing 10% beef tallow serum (manufactured by Gibco)
Eagle's medium (DMEM, manufactured by Flora)
When testing cells in logarithmic growth phase, use 2
The cells were plated in a 24-well culture dish at ~4X10'cells/cm'', and when the cells reached 1-2X1OS cells/cm'' after about 3 days, the test product was dissolved in DMEM containing 10% tallow serum and added. . When testing with cells in arrest phase, 2
Sow ~4XlO'cells/cm'' in a 24-well culture dish until almost confluent (approximately 10 cells/cm'')
When the culture reached 100%, the fetal bovine serum was replaced with a medium containing 0.5% bovine serum albumin, and the test product was added after culturing for about 2 weeks.

The NGF C degree was measured in the same manner as in the case of L-Mail cells.

The results of measuring the increase in NGF content using gallic acid and pyrogallol-4-carboxylic acid as test products are shown in Figure 2.
The GF induction effect is 0.05 to 0.0 when gallic acid (-〇-) is used. 7-8 times more significant NG at 1mM concentration
It shows the ability to induce F production, and pyrogallol-4-carboxylic acid (
--.-1) showed about 4 times the ability to induce NGF production at a concentration of 0.2 mM.

Example l Injectable formulation gallic acid 6mg additive
45 mg total 51 mg After mixing in the above ratio, dissolve in distilled water for injection, aseptically dispense into vials at 5 m/each and freeze-dry to prepare an injection preparation. This injection preparation is dissolved in 5 ml of water for injection before use.

Example 2 Injection formulation pyrogallol-4-carboxylic acid 6mg additive
45 mg total 51 mg After mixing in the above ratio, dissolve in distilled water for injection, aseptically dispense 5 ml into vials and freeze-dry to prepare an injection preparation. This injection preparation is dissolved in 5 ml of distilled water for injection.

[Brief explanation of the drawing]

FIG. 1 is a curve showing the inducing effect of nerve growth factor on L-Mm cells, and FIG. 2 is a curve showing the inducing effect of nerve growth factor on astroglial cells.

Claims (7)

[Claims] (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ A therapeutic/preventative agent for neurological diseases containing a carboxylic acid represented by or a non-toxic salt thereof as an active ingredient. (2) Claim 1 in which the carboxylic acid is gallic acid
Agents for treating and preventing neurological diseases as described in Section 1. (3) The agent for treating and preventing neurological diseases according to claim 1, wherein the carboxylic acid is pyrogallol-4-carboxylic acid. (4) Claim 1 in which the neurological disease is a cranial nerve disease
Agents for treating and preventing neurological diseases as described in Section 1. (5) The agent for treating and preventing a neurological disease according to claim 1, wherein the cranial nerve disease is a neurological disease caused by degeneration of brain nerve cells. (6) The agent for treating and preventing a neurological disease according to claim 5, wherein the neurological disease caused by degeneration of brain nerve cells is dementia. (7) The agent for treating and preventing a neurological disease according to claim 6, wherein the dementia is Alzheimer's type dementia.