JP5548839B2 - Preventive or therapeutic agent for hearing loss or tinnitus - Google Patents

Description

  The present invention relates to an effective means for the treatment and prevention of hearing loss and tinnitus. More specifically, the present invention relates to a preventive / therapeutic agent for age-related hearing loss or noise-induced hearing loss or tinnitus and its use. The present invention also relates to a screening method for a substance effective for the prevention / treatment of age-related hearing loss, noise-induced hearing loss, or tinnitus.

  With the spread of noise in factories and recently, portable music players, etc., there are increasing opportunities to be exposed to loud environments not only for young people but also for a wide range of ages. Such environmental stress has been pointed out to promote the onset of noise and age-related hearing loss, and is a serious problem from the viewpoint of industrial occupational health. A decrease in hearing ability may lead to a serious decrease in communication ability, and it is very important to protect yourself from the threat (ie, noise) in the current aging society. Both age-related hearing loss and noise-induced hearing loss are sensorineural hearing loss, and are caused by loss of hair cells in the inner ear, degeneration of nerve fibers based on the loss, and loss of spiral ganglion cells. Therefore, treatment is very difficult, and development of a new treatment method is urgently required. Furthermore, sensorineural hearing loss such as age-related hearing loss and noise-related hearing loss is a major cause of tinnitus. Therefore, if it is possible to prevent and treat age-related deafness and noise-induced hearing loss, tinnitus can be prevented and treated.

Puffenberger EG et al., Cell 79 (7): 1257-1266 (1994) Matsushima Y et al., Mamm Genome 13 (1): 30-35 (2002) Gariepy CE et al., J Clin Invest 102 (6): 1092-1101 (1998) Kapur RP et al., Neuron 7 (5): 717-727 (1991) Trigueiros-Cunha N et al., Eur J Neurosci 18 (9): 2653-2662 (2003) Legan PK et al., Neuron 28 (1): 273-285 (2000) Vazquez AE et al., Hear Res 194 (1-2): 87-96 (2004)

  In view of the above background, an object of the present invention is to provide an effective means for preventing / treating age-related hearing loss, noise-induced hearing loss, or tinnitus.

In order to solve the above problems, the present inventors have focused on endothelin receptor B (Ednrb). Ednrb is one of the G protein receptors and is expressed in intestinal ganglia and pigment cells. The inner ear has pigment cells, which are intermediate cells that maintain the high K ⁺ concentration of the inner lymph fluid, and K ⁺ is taken up by hair cells to amplify the cochlear microphone potential and exert hearing. It plays an important role. Ednrb knockout mice lack intermediate cells and are known as models of Waardenberg-Shar syndrome that develop megacolon and hearing loss. A homozygous individual of piebald-lethal which is a mutant mouse of Ednrb due to spontaneous onset presents vitiligo and megacolon, and dies in about one month due to a deficiency of intestinal ganglion cells derived from the neural crest (Non-patent Document 1). Similarly, it has been reported that WS4 mouse, which is a mutant mouse of Ednrb, develops congenital hearing loss (Non-patent Document 2). However, there is no report on the effect of overexpression of Ednrb in the nervous system on hearing. The present inventors thought that Ednrb might be involved in hearing control and decided to conduct various studies. First, a test system using a Dbh / Ednrb transgenic mouse (see Non-Patent Document 3 for Ednrb-Tg) forcibly expressing Ednrb under the dopamine β hydroxylase promoter was constructed. Dopamine β hydroxylase is an enzyme that converts dopamine, a neurotransmitter, into noradrenaline. Since noradrenaline is a synaptic transmitter released from noradrenergic neurons, dopamine β-hydroxydase is present in synaptic vesicles of noradrenergic / adrenergic neurons, as a specific marker, as well as neuroendocrine cells. Are known. Mouse DbH-nlacZ, in which nlacZ is linked downstream of the human DbH promoter (5.8 kb), expresses lacZ in the nerve probe, and thereafter, sustained expression is observed in the enteric nervous system (Non-patent Document 4). Furthermore, endogenous DbH is expressed in the cap membrane in the peripheral nerve and inner ear (Non-patent Document 5).

  As a result of the examination, in Dbh / Ednrb-Tg mice, expression of Ednrb was observed in the cap of the inner ear, and the mice were resistant to noise-induced hearing loss. The cap membrane plays an important role in hearing, and in mice knocking out α-tectorin specifically expressed in the cap membrane, the cap membrane disappears and the hearing is reduced (Non-patent Document 6). This result suggests that high expression of Ednrb in the cap of the inner ear is effective in preventing noise-induced hearing loss. On the other hand, the present inventors constructed an original screening system and screened a substance that increases the expression of Ednrb at the cellular level. As a result of screening, 62 types of extracts and 265 types of compounds were identified. Next, we decided to examine the effect on hearing loss by taking Lutelion as an example. At that time, a novel evaluation system using wild-type mice was used. Much noise-induced hearing loss experiments using mice often cause permanent hearing loss, and very few models of transient hearing loss are caused by the noise level exposed in daily life. Further, in the previously reported transient hearing loss model, the time to recovery is too short (Non-Patent Document 7), and the measurement timing is difficult. Therefore, we used wild-type mouse C57BL / 6 to give 70-100 dB of noise for 5-60 minutes, and confirmed that hearing was restored the next day, and made an evaluation system capable of inducing transient noise-induced hearing loss. . As a result of the examination by the evaluation system, mice administered with luteolin showed noise tolerance. That is, luteolin was found to have a preventive effect on noise-induced hearing loss. In addition, in mice administered with luteolin, Ednrb expression was observed in the cap of the inner ear, as in Dbh / Ednrb-Tg mice. As a result of further investigation, it was found that luteolin is effective not only for noise-induced hearing loss but also for age-related hearing loss.

  On the other hand, when a new test method using human hearing as an index was designed and the effect of luteolin was examined, it was proved that luteolin was effective for noise-induced hearing loss. It was also shown that the test method is effective as an evaluation system for hearing loss and has high utility value. As a result of further studies, luteolin was also found to reduce tinnitus.

The above series of studies suggested that age-related deafness, noise-induced hearing loss, and tinnitus can be prevented and treated by promoting the expression of Ednrb in the cap of the inner ear. In other words, it was found that a substance having an action of increasing the expression of Ednrb is effective in preventing / treating age-related hearing loss, noise-induced hearing loss, and tinnitus. In addition, we have succeeded in creating an evaluation system useful for finding substances effective for the prevention and treatment of these diseases and conditions. As a result of further studies, the present inventors have succeeded in creating a method and system useful for detecting / predicting age-related hearing loss or noise-induced hearing loss or tinnitus.
[1] A prophylactic / therapeutic agent for age-related hearing loss, noise-induced hearing loss, or tinnitus, comprising a substance that increases the expression of endothelin receptor B.
[2] The substance is an avocado extract, an amacha extract, an arnica extract, an Acacia catechu extract, an enamel extract, an orange extract, an orange extract, a seaweed extract, a cuckoo extract, a chamomile extract, a clara extract, a chlorella extract, a gentian extract, a comfrey Extract, cherry extract, hawthorn extract, elderberry extract, yarrow extract, mallow extract, soybean extract, thyme extract, oolong tea extract, spruce extract, neem extract, ginseng extract, holly extract, bilberry extract, loquat extract, grape extract, peppermint extract, Button pi extract, Melissa extract, cornflower extract, Yuzu extract, rooibos extract, lemongrass extract, forsythia extract, rosemary extract, Rome Mitsuru extract, wild thyme extract, salvia extract, rose extract, lavender extract, chitosan extract, silk extract, milk extract, glutamic acid extract, yeast extract, pig blood extract, pig placenta extract, pig skin extract, royal jelly extract, perilla seed extract, primrose From any one of the extracts selected from the group consisting of extract, hermanus extract, buckwheat extract, baobab extract, okra extract, candle tree extract, spinach extract, almond extract and lychee extract, or 265 compounds shown in FIGS. The prophylactic / therapeutic agent according to [1], which is any compound selected from the group consisting of:
[3] The prophylactic / therapeutic agent according to [1], wherein the substance is luteolin.
[4] A composition for preventing / treating age-related hearing loss or noise-induced hearing loss or tinnitus, comprising the preventive agent according to any one of [1] to [3].
[5] The composition for prevention / treatment according to [4], which is a medicine or food.
[6] Aging characterized by administering the prophylactic / therapeutic agent according to any one of [1] to [3] or the prophylactic / therapeutic composition according to claim 4 or 5 to a subject. Prevention / treatment of deafness or noise-induced hearing loss or tinnitus.
[7] A method for producing a transient noise-induced hearing loss model mouse, characterized by applying a noise load of 70-100 dB for 5-60 minutes to a mouse.
[8] A screening method for a substance effective for prevention / treatment of noise-induced hearing loss or tinnitus, including the following steps (1) to (4):
(1) preparing a plurality of mice and dividing them into a test group and a control group;
(2) administering a test substance to the test group;
(3) A step of measuring a hearing loss of 8 kHz to 20 kHz before and after a noise load of 80 to 112 dB for 5 to 60 minutes and determining a hearing reduction level due to the noise load for the test group after step (2);
(4) Compare the hearing loss level determined in step (3) with the hearing loss level determined for the control group treated in the same way as the test group, except that the test substance is not administered. Determining the effectiveness of the substance.
[9] The screening method according to [8], wherein the noise load is 82 dB and a noise load for 10 minutes.
[10] A screening method for a substance effective for prevention / treatment of noise-induced hearing loss or tinnitus, including the following steps (1) to (3):
(1) measuring the hearing ability of the subject between 1 kHz and 20 kHz before and after the noise load, and determining the level of hearing loss due to the noise load;
(2) administering a test substance to a subject;
(3) After step (2), measuring the hearing ability of the subject from 1 kHz to 20 kHz before and after the same noise load as the noise load in step (1), and determining a hearing reduction level due to the noise load ;
(4) A step of comparing the hearing loss level determined in step (1) with the hearing loss level determined in step (3) and determining the effectiveness of the test substance based on the comparison result.
[11] The screening method according to [10], wherein the noise load is 75 to 95 dB and a noise load of 10 minutes.
[12] Detection of age-related deafness or noise-related deafness or tinnitus, including a sound generator capable of generating sounds in the range of 8 kHz to 20 kHz, a sound range controller, a volume controller, and an external output device Or a prediction system.
[13] The detection or prediction system according to [12], further including a detection electrode, an amplification device that amplifies a signal from the detection electrode, and an analysis device that analyzes the amplified signal.
[14] Detection of age-related deafness or noise-related deafness or tinnitus, including a sound generator capable of generating sounds in the range of 8 kHz to 20 kHz, a sound range control device, a volume control device, and an external output device Or a method of operating a prediction system comprising:
An operation method comprising: a step in which a sound generation device generates a sound in a range of 8 kHz to 20 kHz under control of a sound range control device and a volume control device; and a step in which an external output device outputs the generated sound.
[15] A sound generator capable of generating sound in the range of 8 kHz to 20 kHz, a range controller, a volume controller, an external output device, a detection electrode, and a signal from the detection electrode are amplified. A method for operating a system for detecting or predicting age-related hearing loss or noise-induced hearing loss or tinnitus, comprising an amplification device and an analysis device for analyzing the amplified signal,
Under the control of the sound range control device and the sound volume control device, the sound generating device generates a sound in the range of 8 kHz to 20 kHz, the step of outputting the generated sound by the external output device, and the detection electrode detects An operation method comprising the steps of an amplifying device for amplifying an electroencephalogram signal, and an analyzing device for analyzing the amplified electroencephalogram signal.
[16] A method for detecting or predicting age-related deafness or noise-induced deafness or tinnitus, wherein the hearing ability of a subject is measured from 8 kHz to 20 kHz.

Ednrb-Tg noise resistance deafness. (a-d) Immunohistochemical staining of Ednrb in the inner ear of 7 month old Dbh / Ednrb-Tg mice (c, d) and wild type mice (a, b). In Dbh / Ednrb-Tg mice, expression of Ednrb is observed in the cap membrane (arrow) (d). (E) ABR threshold before noise of 7 month old Dbh / Ednrb-Tg mice (n = 4) and wild type mice (n = 4). There is no significant difference between 4kHz and 12kHz. (Data not shown for f and 4 kHz). 7-month-old Dbh / Ednrb-Tg mice and wild-type mice were subjected to transient deafness by giving a noise of 82 dB for 10 minutes. ABR threshold change before and after noise exposure was shown. At 4 kHz and 12 kHz, Dbh / Ednrb-Tg mice have a small threshold change before and after noise compared to wild type (WT). (Data not shown for 4 kHz. Mann-Whitney U test, p <0.01) Noise-induced hearing loss resistance due to luteolin. (A-d) Immunohistochemical staining of Ednrb in the inner ear of 5-month-old luteolin-administered group (a, b) and control group (c, d). In the luteolin administration group, expression of Ednrb is observed in the cap membrane (arrow) (d). (E) A 5-month-old C57BL / 6 mouse was allowed to freely drink a luteolin solution (2.5 mg / ml) for 1 month. The noise was exposed at 82dB for 10 minutes, and the ABR threshold change at 12kHz before and after the noise exposure was measured. The luteolin-administered group (7.5, n = 9) has less threshold change than the control group (17.5, n = 8). (Mann-Whitney U test, p <0.05) Age-related deafness resistance by luteolin. (A) Experimental scheme. ABR of 5-month-old C57BL / 6 mice was measured, and ABR was measured by drinking luteolin solution (2.5 mg / ml) freely for 2 months. (B) ABR threshold change at 4kHz and 12kHz. Compared with the control group (ctrl, n = 8), the threshold change was suppressed in the luteolin-administered group (# 521, n = 8). (Mann-Whitney U test, p <0.01) Detection of human age-related deafness. For 20s (n = 20), 30s (n = 10), and 40s (n = 3), hearing was measured at 1kHz, 4kHz, 8kHz and 12kHz. At the high frequency of 12 kHz, which is not performed by normal hearing tests, hearing loss was observed in the 40s. (Mann-Whitney U test, p <0.05) Detection of human noise-induced hearing loss. 2 groups of people aged 20-22 who usually use a portable music player for less than 3 days a week (n = 10) and who use an MP3 player for more than 1 hour every day (n = 15) The subjects listened to 75-80dB of music for 10 minutes, and the change in threshold of hearing was measured before and after that. For those who have used a portable music player for over an hour, there was a large change in the hearing threshold at 12 kHz. (Mann-Whitney U test, p <0.01) A list of compounds that have been shown to increase endothelin receptor B expression. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. FIG. 17 is a continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. Continuation of FIG. FIG. 23 is a continuation of FIG. Continuation of FIG. Continuation of FIG. FIG. 26 is a continuation of FIG. Continuation of FIG. FIG. 28 is a continuation of FIG. Continuation of FIG. An example of a detection / prediction system for age-related hearing loss or noise-induced hearing loss or tinnitus.

(Preventive / therapeutic agent for age-related hearing loss or noise-induced hearing loss or tinnitus)
The fact that transgenic mice forcibly expressing endothelin receptor B in inner ear pigment cells, which play an important role in hearing, showed resistance to noise-induced hearing loss. Luteolin, which promotes expression of endothelin receptor B, was administered. The first aspect of the present invention is based on the fact that mice show noise tolerance, and that the sensory deafness such as age-related hearing loss and noise-induced hearing loss is the main cause of tinnitus. Provided is a prophylactic / therapeutic agent for age-related hearing loss or noise-induced hearing loss or tinnitus, which contains a substance that increases the expression of B (hereinafter also referred to as “Ednrb expression increasing substance”).

  “Endothelin receptor B” (GeneID: 1910, Entrez Gene, NCBI) is a molecule belonging to the G protein-coupled receptor family. The amino acid sequence registered in the public database as endothelin receptor B is shown in the attached sequence listing as SEQ ID NO: 1 (DEFINITION: endothelin receptor type B [Homo sapiens]. ACCESSION: AAP32295, Entrez Protein, NCBI) and SEQ ID NO: 3 ( DEFINITION: endothelin receptor type B. ACCESSION: AAA52342, Entrez Protein, NCBI). In addition, the mRNA sequence corresponding to the amino acid sequence of SEQ ID NO: 1 is SEQ ID NO: 2 (DEFINITION: Homo sapiens endothelin receptor type B (EDNRB) mRNA, complete cds. ACCESSION: AY275463, Entrez Nucleotide, NCBI). The mRNA sequence corresponding to the amino acid sequence is represented by SEQ ID NO: 4 (DEFINITION: Homo sapiens endothelin receptor type B (EDNRB) mRNA, complete cds. ACCESSION: L06623, Entrez Nucleotide, NCBI).

  The “substance that increases the expression of endothelin receptor B (Ednrb expression increasing substance)” is a substance that directly or indirectly promotes the expression of endothelin receptor B. Although not limited to this, it can be determined by the evaluation method (reporter assay using an Ednrb promoter) shown in the below-mentioned Example whether it corresponds to an Ednrb expression increasing substance.

  “Prophylactic / therapeutic agent” means preventive and / or therapeutic effect on target disease or pathological condition such as age-related hearing loss or noise-induced hearing loss or tinnitus (hereinafter these three are collectively referred to as “target disease”). Refers to drugs that exhibit A typical preventive effect is to prevent or delay the onset (onset) of the target disease. On the other hand, the therapeutic effect includes alleviating the symptoms of the target disease (lightening), preventing or delaying the worsening of symptoms. The latter (preventing or delaying deterioration) can be regarded as one of the preventive effects in terms of preventing aggravation. As described above, the preventive effect and the therapeutic effect are partially overlapping concepts, and it is difficult to clearly distinguish them from each other, and there is little practical benefit of doing so. In addition, as long as some preventive effect or therapeutic effect is shown with respect to a target disease, it corresponds to the preventive / therapeutic agent with respect to a target disease.

  Age-related deafness is sensorineural hearing loss caused by aging and is also called senile deafness. The cause is thought to be aging of the auditory center and sensory cells. Age-related hearing loss almost always occurs in both ears, and symptoms worsen with age. Age-related hearing loss often involves dizziness and tinnitus. On the other hand, noise-induced hearing loss is a hearing loss caused by noise. Noise-induced hearing loss is broadly divided into “professional hearing loss” caused by working for a long time under noise and “acoustic hearing loss (acoustic trauma)” caused by exposure to high volume at a concert or the like. Often accompanied by tinnitus. Unless otherwise specified, “deafness” is used in this specification as a term encompassing age-related hearing loss and noise-related hearing loss.

  In one embodiment of the present invention, as an Ednrb expression-enhancing substance, an avocado extract, an amacha extract, an arnica extract, an Acacia catechu extract, an enamel extract, an orange extract, an orange extract, a seaweed extract, a cuckoo extract, a chamomile extract, a clara extract, a chlorella extract , Gentian extract, Comfrey extract, Sakura extract, Hawthorn extract, Elderberry extract, Achillea millefolium extract, Zeni mushroom extract, Soybean extract, Thyme extract, Oolong tea extract, Spruce (daidai) extract, Neem (Indian sendan) extract, Panax ginseng extract, Giant peony (Yakan) Extract, Bilberry Extract, Biwa Extract, Grape Extract, Peppermint Extract, Buttonpi (Button) Extract, Melissa Extract, Cornflower Extract, Yuzu Extract, Louis Extract, lemongrass extract, lotus extract, rosemary extract, roman chamomile extract, wild thyme extract, salvia extract, rose extract, lavender extract, chitosan extract, silk (sericin) extract, milk extract, glutamic acid extract, yeast extract, pork blood extract , Pork placenta extract, pork skin extract, royal jelly extract, perilla extract, camellia extract, hermanus extract, duckweed extract, baobab extract, okra extract, candle tree extract, spinach extract, almond extract and lychee extract Or any compound selected from the group consisting of 265 compounds described in FIGS. These substances have been found by the present inventors through an original screening system using the Ednrb promoter.

  The extraction solvent used to obtain each extract is a lower alcohol such as methanol, ethanol, propyl alcohol, isopropyl alcohol, butanol or isobutanol or a hydrous lower alcohol, a polyhydric alcohol such as propylene glycol or 1,3-butylene glycol. Or water-containing polyhydric alcohol, dimethylsulfoxide (DMSO), acetone, dioxane, methyl ethyl ketone, acetonitrile, acetic acid ethyl ester, butyl methyl ketone, diethyl ether, phenoxyethanol, octyldodecyl myristate, polysorbate 80, dichloromethane, xylene, trichloroethylene, Examples thereof include organic solvents such as carbon tetrachloride, benzene, chloroform, and toluene, and water. The hydrous lower alcohol is a mixed solution of lower alcohol and water, preferably the lower alcohol / water ratio is 10/90 to 90/10 (V / V: volume ratio), more preferably 30 / 70 to 80/20 (V / V: volume ratio). Similarly, the water-containing polyhydric alcohol is a mixed liquid of polyhydric alcohol and water, preferably a polyhydric alcohol / water ratio of 10/90 to 90/10 (V / V: volume ratio), more preferably. Is 30 / 70-80 / 20 (V / V: volume ratio).

  The extraction operation can be performed by conventional methods such as cold immersion, digestion, heating reflux, and percolation method. Instead of extraction with a solvent, for example, a crude drug extract may be obtained by a steam distillation method or a supercritical extraction method. The extract can be separated and purified by activated carbon treatment, liquid-liquid distribution, column chromatography, liquid chromatography, or the like.

In the following, particularly preferred solvents are listed for each extract.
Avocado extract / Butylene glycol Achacha extract / Butylene glycol Arnica extract / Butylene glycol Asenya extract / Butylene glycol Enmeiso extract / Ethanol Ogon extract / Butylene glycol Orange extract / Propylene glycol Seaweed extract / Propylene glycol or Butylene glycol Cuckon extract or Butylene glycol or ethanol Chamomile extract or ethanol or octyldodecyl myristate Clara extract or butylene glycol / ethanol mixed solution or butylene glycol Chlorella extract or Butylene glycol Gentianana extract or Butylene glycol Comfree extract Butylene glycol cherry extract, butylene glycol hawthorn extract, Butylene glycol Elderberry extract / Butylene glycol Achillea millefolium extract / Butylene glycol Xenopus extract / Butylene glycol Soybean extract / Butylene glycol or ethanol Thyme extract / Butylene glycol Oolong tea extract / Ethanol spruce (daidai) extract / Butylene glycol Neem (Indonesian) extract ・ Butylene glycol Panax Ginseng extract ・ Butylene glycol Butterberry extract ・ Butylene glycol / ethanol mixed solution Bilberry extract ・ Butylene glycol Biwa extract ・ Ethanol Grape extract ・ Butylene glycol Peppermint extract ・ Butylene glycol / Polysorbate 80 / Oles-8 phosphoric acid Na mixed solution Buttonpi ( Tan) extract, butylene glycol or ethanol Melissa extract, butylene glycol cornflower extract, butylene glycol yuzu extract, ethanol rooibos extract, butylene glycol lemongrass extract, butylene glycol lotus extract, butylene glycol / ethanol mixed solution rosemary Extract, Butylene Glycol Roman Chamomile Extract, Butylene Glycol Wild Time Extract, Butylene Glycol Salvia Extract, Ethanol Rose Extract, Water Lavender Extract, Ethanol or Butylene Glycol Chitosan Extract, Ethanol Silk (Sericin) Extract, Butylene Glycol Or phenoxyethanol / ethanol mixed solution Milk extract / ethanol Glutamate・ Ethanol or butylene glycol Yeast extract ・ Ethanol, butylene glycol or water Pig blood extract ・ Phenoxyethanol Pig placenta extract ・ Butylene glycol Pork skin extract ・ Butylene glycol Perilla extract ・ Butylene glycol Primula extract ・ Butylene Glycol Oat Extract, Butylene Glycol Baobab Extract, Phenoxyethanol Okra Extract, Water Candle Tree Extract, Water / Butylene Glycol Mixed Almond Extract, Water Lychee Extract, Butylene Glycol

  In a preferred embodiment, luteolin is used as an Ednrb expression increasing substance. As for luteolin, as shown in the Examples section described later, an excellent preventive / therapeutic effect on hearing loss and an effect of reducing tinnitus have been confirmed by animal experiments and human experiments.

  Luteolin (3 ', 4', 5,7-tetrahydroxyflavone) is a kind of flavonoid that is a plant polyphenol component, and is contained in a large amount in perilla, spring chrysanthemum, bell pepper, mint, rosemary, chamomile and the like. There are various glycosides in luteolin. The sugar component constituting the luteolin glycoside is not particularly limited. Examples of sugars are glucose, fucose and galactose. The sugar binding position is 6-C, 8-C, 7-O, etc. of the luteolin molecule. Specific examples of the luteolin glycoside include 6-C-fucosyl luteolin and 6-C-quinovosyl luteolin (see Phytochemistry, 30, 3486, 1991).

  Luteolin is widely used as a raw material for supplements and cosmetics, and is easily available. Luteolin or luteolin glycoside extracted and purified according to a known method can also be used.

(A composition for preventing / treating age-related hearing loss or noise-induced hearing loss or tinnitus)
The second aspect of the present invention provides a composition for preventing / treating age-related hearing loss, noise-induced hearing loss, or tinnitus, which contains the preventive / therapeutic agent of the present invention. Although the form of the composition of this invention is not specifically limited, Preferably it is a pharmaceutical or a foodstuff. Two or more kinds of prophylactic / therapeutic agents may be used in combination.

  The pharmaceutical composition of the present invention can be formulated according to a conventional method. In the case of formulating, other pharmaceutically acceptable ingredients (for example, carriers, excipients, disintegrants, buffers, emulsifiers, suspension agents, soothing agents, stabilizers, preservatives, preservatives, physiological Saline solution and the like). As the excipient, lactose, starch, sorbitol, D-mannitol, sucrose and the like can be used. As the disintegrant, starch, carboxymethylcellulose, calcium carbonate and the like can be used. Phosphate, citrate, acetate, etc. can be used as the buffer. As the emulsifier, gum arabic, sodium alginate, tragacanth and the like can be used. As the suspending agent, glyceryl monostearate, aluminum monostearate, methyl cellulose, carboxymethyl cellulose, hydroxymethyl cellulose, sodium lauryl sulfate and the like can be used. As the soothing agent, benzyl alcohol, chlorobutanol, sorbitol and the like can be used. As the stabilizer, propylene glycol, ascorbic acid or the like can be used. As preservatives, phenol, benzalkonium chloride, benzyl alcohol, chlorobutanol, methylparaben, and the like can be used. As preservatives, benzalkonium chloride, paraoxybenzoic acid, chlorobutanol and the like can be used.

  There are no particular restrictions on the dosage form for formulation, and the pharmaceutical composition of the present invention is provided as, for example, tablets, powders, fine granules, granules, capsules, syrups, injections, external preparations, and suppositories. it can. The pharmaceutical composition of the present invention contains an active ingredient in an amount necessary for obtaining the expected prophylactic / therapeutic effect (that is, a therapeutically effective amount). The amount of the active ingredient in the pharmaceutical composition of the present invention generally varies depending on the dosage form, but the amount of the active ingredient is set, for example, within the range of about 0.1% by weight to about 95% by weight so as to achieve a desired dose.

  The pharmaceutical composition of the present invention is applied to a subject by oral administration or parenteral administration (intravenous, intraarterial, subcutaneous, intramuscular or intraperitoneal injection, transdermal, nasal, transmucosal, etc.) depending on the dosage form. The The “subject” here is not particularly limited, but a preferred subject is a human.

  The dosage of the pharmaceutical composition of the present invention is set so as to obtain the expected prophylactic or therapeutic effect. In setting a therapeutically effective dose, symptoms, patient age, sex, weight, etc. are generally considered. A person skilled in the art can set an appropriate dose in consideration of these matters, for example, once to several times a day, once every two days, or once every three days. Times can be adopted. In preparing the administration schedule, the patient's medical condition and the duration of effect of the active ingredient can be taken into consideration.

  As described above, one embodiment of the present invention is a food composition containing the preventive / therapeutic agent of the present invention. Examples of “food composition” in the present invention include general foods (cereals, vegetables, meat, various processed foods, confectionery, milk, tea beverages, soft drinks, alcoholic beverages, etc.), dietary supplements (supplements, nutritional drinks) Etc.), food additives, foods for pets, nutritional supplements for pets. Examples of the shape of the food composition of the present invention include powders, granule powders, gums, tablets, pastes, and liquids. By providing in the form of a food composition, it becomes easy to ingest the active ingredient of the present invention on a daily basis or continuously.

  The food composition of the present invention preferably contains an active ingredient in an amount that can be expected to have a preventive or therapeutic effect. The amount added can be determined in consideration of the medical condition, health status, age, sex, weight, etc. of the person to whom it is used.

(Animal model production method)
The fourth aspect of the present invention provides a method for producing a transient noise-induced hearing loss model mouse. In the production method of the present invention, a noise load of 70 to 100 dB for 5 to 60 minutes is given to a mouse to induce transient noise-induced hearing loss. In the case of the mouse prepared as described above, the time required for recovery from hearing loss is longer than that of a previously reported animal model (1 to 2 days). Since it exhibits such characteristics, it has a high utility value as an experimental animal used for screening a substance effective for hearing loss, for example.

  The kind and origin of the mouse used for the production method of the present invention are not particularly limited. For example, wild-type mice C57BL / 6, BALB / c, ICR, etc. (all of which are available from vendors such as Japan SLC) can be used. A specific example of a noise load is a noise load of 82 dB for 10 minutes.

(Screening method using animal model)
The fifth aspect of the present invention provides a method (in vivo screening method) for screening a substance effective for prevention / treatment of noise-induced hearing loss or tinnitus using an animal model. In the screening method, the above animal model (fourth aspect) is used. Specifically, the following steps (1) to (4) are performed. For matters not specifically mentioned (test substance, noise load, mouse type, etc.), the corresponding explanations described above are incorporated.
(1) preparing a plurality of mice and dividing them into a test group and a control group;
(2) administering a test substance to the test group;
(3) About the test group after step (2), measuring the hearing ability of 8 kHz to 20 kHz before and after noise loading of 80 to 112 dB, 5 to 60 minutes, and determining the level of hearing loss due to noise loading;
(4) Compare the hearing loss level determined in step (3) with the hearing loss level determined for the control group treated in the same way as the test group, except that the test substance is not administered. Step of determining the effectiveness of a substance

  In step (1), a plurality of mice are prepared and divided into a test group and a control group. The number of individuals included in the test group and the control group is not particularly limited. In general, as the number of individuals used increases, a more reliable result can be obtained. However, handling a large number of individuals at the same time is difficult in terms of securing and operating (including breeding) the individuals to be used. Therefore, for example, the number of individuals included in each group is 1 to 50, preferably 2 to 30, and more preferably 3 to 20. Normally, the test group and the control group should have the same number of individuals.

  In step (2), the test substance is administered to the test group. The mode of administration of the test substance is not particularly limited. For example, food or drinking water containing the test substance is prepared and ingested. Alternatively, a test substance or a solution containing the test substance is prepared and administered. Examples of the administration method include oral administration, nasal administration, tracheal administration, intravenous, intraarterial, subcutaneous, intramuscular or intraperitoneal injection. The test substance may be administered multiple times. In that case, each dose may be the same or different. You may decide to administer continuously. The control group is reared under the same conditions except that the test substance is not administered.

  In step (3), a noise load is applied to the test group and the hearing is measured before and after the noise load to determine the level of hearing loss due to the noise load. In the present invention, a noise load of 80 to 112 dB and 5 to 60 minutes is employed. Preferably, the noise load is 82 dB for 10 minutes. On the other hand, the measured hearing is in the range of 8 kHz to 20 kHz. Preferably 12 kHz hearing is measured. For example, an auditory brainstem reaction can be used to determine the hearing loss level. The “auditory brainstem reaction” is a potential in the brainstem (brainstem reaction) obtained by exciting the auditory nervous system. By analyzing the auditory brainstem response (electroencephalogram) when a predetermined sound stimulus is applied, the level of hearing ability can be examined with good reproducibility. Test methods using the auditory brainstem reaction are widely used to determine hearing loss. For details of the test method using the auditory brainstem reaction, refer to the ABR Handbook (Edited by Kimitaka Kaga (Kanehara Publishing)). Instead of the auditory brainstem reaction, a pure tone hearing test or the like may be used.

  In step (4), the effectiveness of the test substance is determined using the hearing loss level of the test group and the hearing loss level of the control group. Specifically, the hearing loss level determined in step (3) (ie, the hearing loss level of the test group) and the hearing loss level determined for the control group treated in the same manner as the test group, except that the test substance is not administered. To determine whether the test substance is effective. At this time, an indicator that “a small hearing loss level is effective for prevention / treatment of noise-induced hearing loss or tinnitus” is used. Therefore, when the hearing loss level of the test group is smaller than the hearing loss level determined for the control group, that is, when the hearing loss level is improved by administration of the test substance, prevention of noise-induced hearing loss or tinnitus It will be determined that the test substance is effective for treatment.

  Steps (1) to (4) may be performed again using a plurality of test compounds that have been confirmed to be effective to narrow down highly effective substances.

  A substance selected by the screening method of the third aspect can be used as a test substance of the screening method of this aspect. That is, the screening method of the third aspect may be used for primary screening, and secondary screening may be performed by the screening method of this aspect. If the stepwise screening is carried out in this way, the target substance can be found more efficiently.

(Screening method by subjects)
The sixth aspect of the present invention provides a method (in vivo screening method) for screening a substance effective for prevention / treatment of noise-induced hearing loss or tinnitus using a subject. In the screening method of this aspect, the following steps (1) to (4) are performed. In addition, about the matter which is not mentioned especially, the corresponding description in the said 5th aspect is used.
(1) A step of measuring the hearing ability of the subject from 1 kHz to 20 kHz before and after the noise load, and determining the level of hearing loss due to the noise load.
(2) A step of administering a test substance to a subject
(3) After step (2), measuring the hearing ability of the subject from 1 kHz to 20 kHz before and after the same noise load as the noise load in step (1), and determining a hearing reduction level due to the noise load
(4) comparing the hearing loss level determined in step (1) with the hearing loss level determined in step (3), and determining the effectiveness of the test substance based on the comparison result

  In step (1), the subject is given a noise load, and the hearing ability of 1 kHz to 20 kHz, which is a frequency range that has been clarified by the present inventors, is effective in detecting transient hearing loss. Measure before and after. Then, the level of hearing loss due to noise load (the level of hearing loss before administration of the test substance) is determined from the measurement result. The noise load here is, for example, 75 to 95 dB for 10 minutes so that transient noise-induced hearing loss occurs. Preferably, a noise load of 80 dB for 10 minutes is employed. On the other hand, the frequency at which hearing measurement is performed is preferably 12 kHz. For example, an auditory brainstem reaction or a pure tone hearing test can be used to determine the hearing loss level.

  In the subsequent step (2), the test substance is administered to the subject. The administration method, the number of administrations, the administration period, the administration interval, etc. are not particularly limited. For example, the test substance is administered by oral administration, nasal administration, tracheal administration, intravenous, intraarterial, subcutaneous, intramuscular or intraperitoneal injection. The frequency of administration is, for example, 1 to 100 times. The administration period is, for example, 1 day to 3 months. Note that the following steps (3) and (4) may be performed over time, and the results may be used to determine the effectiveness of the test substance.

  In step (3), the test subject is again given a noise load, and the hearing ability of 8 kHz to 20 kHz is measured before and after that to determine the hearing reduction level (hearing reduction level after administration of the test substance) due to the noise load. The noise load here is the same as the noise load adopted in step (1).

  In the next step (4), the effectiveness of the test substance is determined using the hearing loss level determined before and after administration of the test substance. Specifically, the hearing loss level before administration of the test substance is compared with the hearing loss level after administration of the test substance to determine whether or not the test substance is effective. At this time, an indicator that “a small hearing loss level is effective for prevention / treatment of noise-induced hearing loss or tinnitus” is used. Therefore, when the hearing loss level after administration of the test substance is smaller than the hearing loss level before administration of the test substance, that is, when improvement in the hearing loss level is observed before and after administration of the test substance, noise-induced hearing loss or tinnitus It is determined that the test substance is effective for the prevention and treatment of

  Also in the screening method of this aspect, steps (1) to (4) may be performed again using a plurality of test compounds that have been confirmed to be effective to narrow down highly effective substances.

  A substance selected by the screening method of the third aspect can be used as a test substance of the screening method of this aspect. That is, the screening method of the third aspect may be used for primary screening, and secondary screening may be performed by the screening method of this aspect. Similarly, the screening method of the fifth aspect may be used for primary screening. Furthermore, the screening method of the third aspect and the screening method of the fifth aspect may be used for primary screening and secondary screening, respectively, and tertiary screening may be performed by the screening method of this aspect. As described above, if the stepwise screening is performed, the target substance can be found more efficiently.

(Detection / prediction of age-related hearing loss or noise-induced hearing loss or tinnitus)
A further aspect of the present invention relates to a method that can detect or predict age-related hearing loss or noise-induced hearing loss or tinnitus with high sensitivity. As a result of the study by the present inventors, transient noise-induced hearing loss can be detected with high sensitivity by examining the hearing level of 8 kHz to 20 kHz (especially 12 kHz) that is not measured by a normal hearing test. Knowledge was obtained. It has also been found that if the frequency range is measured, a sign that age-related hearing loss is beginning to progress can be detected with high sensitivity. Based on these findings, the detection / prediction method of the present invention is characterized by measuring the hearing level of a subject from 8 kHz to 20 kHz (preferably 12 kHz). The subject is preferably a human (subject), but can also be applied to mammals other than humans (for example, pet animals and domestic animals). Examples of mammals other than humans include mice, rats, guinea pigs, hamsters, monkeys, cows, pigs, goats, sheep, dogs and cats. In addition, since the sound range measurable by the normal pure tone hearing test is 125 Hz to 8 kHz, the present invention cannot be carried out using this as it is. In other words, in the present invention, a measurement distinctly different from a normal pure tone hearing test is performed.

  If the method of the present invention is used for the prediction of noise-induced hearing loss or tinnitus, if a decrease in the hearing level is recognized from the measurement results, “there is a high risk of developing noise-induced hearing loss or tinnitus” or “noise-induced hearing loss” Or, there is a possibility of developing tinnitus ". Depending on the degree of decrease in hearing level, the likelihood of developing noise-induced hearing loss or tinnitus is a gradual indicator (for example, 10% or less, 10% -30%, 30% -50%, 50% -80% ).

  On the other hand, when the method of the present invention is used for detection / evaluation of age-related deafness, it indicates that there is a strong sign of age-related deafness as the hearing level decreases significantly. Therefore, in addition to grasping the current state of age-related hearing loss, it is possible to predict future progress.

(Aging / Noise Hearing Loss or Tinnitus Detection / Prediction System)
The present invention further provides a system that can be used to implement the detection / prediction method described above, that is, a detection / prediction system for age-related deafness or noise-induced hearing loss or tinnitus. The system of the present invention includes a sound generator capable of generating a sound in the range of 8 kHz to 20 kHz, a range controller, a volume controller, and an external output device (see FIG. 31). The sound generator only needs to be able to generate sound in the range of 8 kHz to 20 kHz, and may be capable of generating sound in other ranges. The generated sound is typically a pure tone, but may be configured to be able to generate a speech sound or both a pure sound and a speech sound. The sound range control device controls the sound range (frequency) of the sound generated by the sound generation device. Similarly, the volume control device controls the volume of sound generated by the sound generator. The range control device and the volume control device may be configured as one device. The external output device is an interface with the outside, and outputs the sound generated by the sound generator to the outside. Usually, headphones (for example, high-sound headphones for high sound range) are employed as the external output device.

  The above detection / prediction system operates as follows. First, under the control of the sound range control device and the sound volume control device, the sound generation device generates sound in the sound range of 8 kHz to 20 kHz. Subsequently, an external output device outputs the generated sound. In order to detect / predict age-related or noise-induced hearing loss or tinnitus using the system, the target (human or sound) of the specific sound thus generated (sound in the 8 kHz to 20 kHz range) is used. The reaction of mammals other than humans may be observed. For example, when a sound is sensed, a specific action (for example, raising hand, utterance, shaking head, pressing a switch) is performed, and detection / prediction is performed using the presence / absence of the action as an index. In the case of targeting mammals other than humans, for example, it can be determined whether or not a sound has been sensed using behavior (such as barking or crying) or a change thereof as an index.

  In one aspect, the system of the present invention includes a detection electrode, an amplification device that amplifies a signal from the detection electrode, and an analysis device that analyzes the amplified signal in addition to the above devices (see FIG. 31). reference). The detection electrode is attached to a target (preferably a human) and includes a recording electrode, a reference electrode, and a ground electrode. An electroencephalogram electrode, a needle electrode, a dish electrode, or the like can be used as the recording electrode. The amplifying device is a device that amplifies the electroencephalogram signal from the detection electrode. By providing the device, high-sensitivity detection is possible. The amplified signal is analyzed by an analyzer. For example, a PC (personal computer) can be used as an analysis device. The analysis result is displayed on a display, for example.

  The detection / prediction system of this aspect operates as follows. First, under the control of the sound range control device and the sound volume control device, the sound generation device generates sound in the sound range of 8 kHz to 20 kHz. Subsequently, an external output device outputs the generated sound. On the other hand, the amplification device amplifies the electroencephalogram signal detected by the detection electrode. Subsequently, the analysis device analyzes the amplified electroencephalogram signal. Through the series of steps described above, information useful for detection or prediction of age-related hearing loss, noise-induced hearing loss, or tinnitus is obtained as an analysis result. In addition, the system of this aspect is particularly useful when a test is performed on a subject (for example, an infant or a mammal other than a human) that is difficult to express that the sound has been sensed.

1. Ednrb expression sites in wild-type mice and Dbh / Ednrb-Tg mice (1) Method Dbh / Ednrb-Tg mice expressing Ednrb under the dopamine β-hydroxylase promoter have been reported (Gariepy CE, Ohuchi T, Williams SC, Richardson JA, Yanagisawa M. J Clin Invest. 2000 Apr; 105 (7): 925-33. JCI, 2000 Apr; 105 (7): 925-33). Briefly, the mouse Ednrb coding region was incorporated into a Dbh-cDNA expression vector, and a transgenic mouse was prepared according to a standard method. The expression state of Ednrb in the inner ears of 7-month-old Dbh / Ednrb-Tg mice and wild-type mice prepared in this manner was examined by immunohistochemical staining using Ednrb antibody. Reflux fixation was performed using a Bouin solution, and the inner ear was removed. Paraffin sections were prepared and detected using an anti-Ednrb antibody (Chemicon, 1: 2000), Vectastain ABC Kit (vector), Envision kit / HRP (DAB, DAKO), and the nucleus was stained with hematoxylin.

(2) Results
When immunohistochemical staining was performed on the inner ear of Dbh / Ednrb-Tg using Ednrb antibody, expression of Ednrb was observed in the cap of the inner ear corti of Dbh / Ednrb-Tg (FIG. 1d, arrow). It was not seen in the wild type (FIGS. 1a-d).

2. Noise resistance in wild type mice and Dbh / Ednrb-Tg mice (1) Method The mice were anesthetized and the hearing ability of 4 kHz to 40 kHz was measured by ABR. Thereafter, 82 dB of noise was exposed for 10 minutes, and hearing at 4 kHz to 40 kHz was immediately measured by ABR.

(2) Results The audible range for humans (adults) is said to be 20 Hz-20 kHz, but the audible range for mice is 2 kHz-50 kHz. By electroencephalogram measurement using the auditory brainstem response (ABR), Hearing ability of humans and mice can be measured objectively (Akio Yamauchi and Takeji Kajikawa: Sensory map book p37, Kodansha). When the hearing of the Dbh / Ednrb-Tg mouse was measured, the 7-month-old Ednrb-Tg mouse had almost the same hearing as the wild type (Fig. 1e), but it was transient after giving a noise of 82dB for 10 minutes. When the noise-induced hearing loss was induced, the hearing ability of the Ednrb-Tg mice showed noise resistance compared to the wild type (FIG. 1f). This result shows the possibility that resistance to noise-induced hearing loss can be induced by enhancing the expression of Ednrb in the inner ear, such as the cap membrane.

3. Screening of Ednrb Expression Modulating Substance in Test Tube (1) Method For the promoter assay, Dual-Luciferase Reporter Assay System (Promega) was used.
Cells were transfected with (i) a firefly luciferase reporter vector incorporating an Ednrb promoter and (ii) a Renilla luciferase reporter vector incorporating an EF1α (used as an internal standard) promoter using Lipofectamin LTX. The next day, the transfected cells were replated at 1 × 10 ⁴ cells / well in a 96-well plate. The next day, the compound was diluted in a medium containing 0.5% FBS and added to the cells. After 24 hours, the cells were washed with PBS, then lysed with a Pushy Lysate Buffer, luciferase activity was measured with a luminometer, and standardized with EF1α (internal standard).

(2) Results For the purpose of developing a deafness-resistant drug, screening of compounds that increase the expression of Ednrb was performed using cultured cells. Using human cells SK-Mel, we established a luciferase assay screening method by constructing a vector that expresses the luciferase gene downstream of the human and mouse Ednrb translation start sites using a 1 kb promoter. did. As a result of screening, 62 types of extracts listed below and 265 types of compounds (the structures of the respective compounds are shown in FIGS. 6 to 30) were selected.
(List of extracts selected by screening)
Avocado extract (extracted with butylene glycol), Achacha extract (extracted with butylene glycol), Arnica extract (extracted with butylene glycol), Acacia yak extract (extracted with butylene glycol), Enmeiso extract (extracted with ethanol), Ogon extract (butylene) Glycol extract), orange extract (extracted with propylene glycol), seaweed extract (extracted with propylene glycol or butylene glycol), cuckoo extract (extracted with butylene glycol or ethanol), chamomile extract (extracted with ethanol or octyldodecyl myristate), Clara extract (extracted with butylene glycol / ethanol mixed solution or butylene glycol), Chlorella extract (extracted with butylene glycol), Gentian extract (extracted with butylene glycol) ), Comfrey extract (extracted with butylene glycol), cherry extract (extracted with butylene glycol), hawthorn extract (extracted with butylene glycol), elderberry extract (extracted with butylene glycol), yarrow extract (extracted with butylene glycol), Mallow extract (extracted with butylene glycol), soybean extract (extracted with butylene glycol or ethanol), thyme extract (extracted with butylene glycol), oolong tea extract (extracted with ethanol), spruce (extracted with butylene glycol) extract, neem extract (butylene glycol) ), Ginseng extract (extracted with butylene glycol), barley extract (extracted with butylene glycol / ethanol mixed solution), bilberry extract (extracted with butylene glycol) ), Loquat extract (extracted with ethanol), grape extract (extracted with butylene glycol), peppermint extract (extracted with mixed solution of butylene glycol / polysorbate 80 / oleth-8 phosphate), button pi extract (extracted with butylene glycol or ethanol), Melissa extract (extracted with butylene glycol), cornflower extract (extracted with butylene glycol), yuzu extract (extracted with ethanol), rooibos extract (extracted with butylene glycol), lemongrass extract (extracted with butylene glycol), forsythia extract (butylene glycol / Extracted with ethanol mixed solution), Rosemary extract (extracted with butylene glycol), Roman chamomile extract (extracted with butylene glycol), Wild thyme extract (extracted with butylene glycol), Salviae Kiss (extracted with ethanol), rose extract (extracted with water), lavender extract (extracted with ethanol or butylene glycol), chitosan extract (extracted with ethanol), silk extract (extracted with butylene glycol or phenoxyethanol / ethanol mixed solution), milk extract (Extracted with ethanol), glutamic acid extract (extracted with ethanol or butylene glycol), yeast extract (extracted with ethanol, butylene glycol or water), pig blood extract (extracted with phenoxyethanol), porcine placenta extract (extracted with butylene glycol), pig Skin extract (extracted with butylene glycol), royal jelly extract, perilla extract (extracted with butylene glycol), camellia extract (extracted with butylene glycol), red pepper extract, buckwheat extract (butylene glyco) Extract), baobab extract (extracted with phenoxyethanol), okra extract (extracted with water), candle tree extract (extracted with water / butylene glycol mixed solution), spinach extract, almond extract (extracted with water), lychee extract (butylene) (Extracted with glycol)

ヒト細胞およびマウス細胞におけるEdnrbのプロモーターアッセイ。コントロールに対しての比活性を示す。*, p<0.05; **, p<0.01; ***, p<0.001

Ednrb promoter assay in human and mouse cells. Specific activity relative to control is shown. *, p <0.05; **, p <0.01; ***, p <0.001

4). Invention of a method for evaluating noise-induced hearing loss using wild-type mice Many experiments of noise-induced hearing loss using mice cause permanent hearing loss, and models of transient hearing loss caused by noise levels exposed in daily life are Very few. Moreover, in the reported transient hearing loss model, the time to recovery is too short (Hear Res, 194: 87-96, 2004), and the timing of measurement is difficult. Therefore, we aimed to create a model animal for transient noise-induced hearing loss. As a result, we confirmed that hearing was restored the next day when 70-100dB, 5-60 minutes of noise was given to wild-type mouse C57BL / 6, and this method was effective in inducing transient noise-induced hearing loss. It turned out to be.

5. Confirmation of the effect of Ednrb expression enhancer on noise-induced hearing loss (1) Method The effect of compound luteolin selected by screening on noise-induced hearing loss was examined. Luteolin aqueous solution was administered to 5 month old wild type C57BL / 6 mice by free drinking (for 1 month), and the expression state of Ednrb in the inner ear cap membrane was examined. On the other hand, similarly, 82 dB, 10 minutes of noise was exposed to mice administered with luteolin, and changes in the ABR threshold at 12 kHz before and after noise exposure were measured.

(2) Results Luteolin, one of the compounds that increase the expression of Ednrb in both mouse and human cells, was administered to a 5-month-old wild-type C57BL / 6 mouse by free drinking and ingested for 1 month. As a result, the expression of Ednrb was observed in the inner ear Corti cap membrane as in the Ednrb-Tg mouse (FIG. 2d, arrow). Furthermore, when the luteolin-treated mice were exposed to noise and the hearing levels before and after the noise were compared, the luteolin-treated group showed resistance to noise-induced hearing loss at a statistically significant level at 12 kHz ( FIG. 2e). Thus, it was shown that luteolin selected as a compound that increases the expression of Ednrb is effective for noise-induced hearing loss.

6). Confirmation of the effect of Ednrb expression enhancer on age-related hearing loss (1) Method
After measuring the ABR of 5-month-old C57BL / 6 mice, the luteolin solution (2.5 mg / ml) was allowed to drink freely for 2 months. Thereafter, ABR was measured again (FIG. 3a).

(2) Results At present, it is considered that the onset mechanism and pathology of noise-induced hearing loss and age-related hearing loss are basically very similar (edited by Takeshi Kubo et al .: Otolaryngology p61, Kinyoshido). Hearing levels were measured for wild-type C57BL / 6 mice that were orally administered luteolin for 5 months to 2 months. In the treated group, it was significantly suppressed to about 2-17 dB, but in the non-treated group, a hearing loss of 15-30 dB was observed in the 4 kHz-32 kHz range for two months of 5-7 months (Fig. 3). This indicates that the progress of age-related deafness can be prevented by oral administration of luteolin. Thus, it was shown that luteolin selected as a compound that increases the expression of Ednrb is also effective for age-related hearing loss.

7). A system that can evaluate / predict noise-related hearing loss in humans with high sensitivity Conventionally, hearing loss at 4 kHz has been used as the most sensitive index for noise-related hearing loss. However, in practice, until hearing loss at 4 kHz is detected, it is about 5 dB when 85 dB of noise is exposed for 20 years and about 10 dB when 90 dB of noise is exposed for 20 years. It has been reported that noise-induced hearing loss (PTS) is induced (edited by Kyoko Kishi et al .: NEW Preventive Medicine / Public Health P287, Nanedo). The present inventors have studied to create a system capable of evaluating / predicting noise-induced hearing loss with high sensitivity. As a result, for transient noise-induced hearing loss, daily level (75-83 dB) music was exposed to subjects for 10 minutes, and the threshold change in hearing was measured before and after that. It became clear that transient noise-induced hearing loss can be detected. The measurement range was 8 kHz-20 kHz, which is not normally measured, in addition to 1 kHz-8 kHz used in normal human hearing tests. Although it was affected by volume, it was particularly preferable at 12 kHz, and transient noise-induced hearing loss was detected in people who used a portable music player for more than an hour every day (Fig. 5). On the other hand, those who usually use MP3 players for less than 3 days a week showed a hearing loss of about 10 dB at 12 kHz (Figure 5). As described above, as a clinical symptom, the present inventors have succeeded in finding a method capable of highly sensitively detecting transient noise-induced hearing loss at a level that could not be detected until now. For example, while using a portable music player, transient noise-induced hearing loss can be detected with high sensitivity by playing a sound source of 8 kHz-20 kHz (preferably 12 kHz) when music is interrupted. Can warn of the onset of noise-induced hearing loss. Such a system can be realized by a dedicated device or by incorporating predetermined software into a general-purpose device (for example, a portable music player).

8). A system that can evaluate / predict age-related deafness with high sensitivity in humans In general, it is known that hearing loss in humans decreases from the high frequency range of 8 kHz → 4 kHz → 2 kHz (Takeshi Kubo) Et al .: Otolaryngology p61, Kinyoshido). The present inventors have studied with the aim of creating a system capable of evaluating / predicting age-related hearing loss with high sensitivity. As a result, in addition to 125 Hz-8 kHz used in normal human hearing tests, by measuring 8 kHz-20 kHz (particularly preferably 12 kHz) that is not normally measured, age-related deafness begins to progress. It was clarified that signs of signs (signs) can be detected with high sensitivity, potential age-related hearing loss can be evaluated, and future progress of age-related hearing loss can be predicted (FIG. 4). In other words, it shows that there is a strong sign of age-related deafness as the hearing loss at 8 kHz-20 kHz is significant, so in future hearing tests such as health checkups (group screening), It can be applied as “current evaluation and prediction of progress”.

9. 6. Prevention and treatment of transient noise-induced hearing loss using a system capable of evaluating / predicting noise-induced hearing loss with high sensitivity (1) Method above The effect of luteolin on noise-induced hearing loss was investigated based on the findings presented in. First, the hearing (1,4,8,12,16kHz) of the subject (male in their 30s) was measured before and after noise exposure (75-80dB, 10 minutes of music). Thereafter, luteolin (0.9 m / day) was administered orally for 4 weeks. After that, the hearing (1,4,8,12,16kHz) of the subject (male in their 30s) was measured again before and after noise exposure (75-80dB, 10 minutes of music).

(2) Results As a result of comparing the hearing loss level before and after administration of luteolin, it was shown that it became difficult to cause transient noise-induced hearing loss (10 dB hearing loss at 12 kHz after noise exposure).

<Discussion>
Sensorineural hearing loss caused by induction of cell death in inner ear hair cells is a deafness that affects a wide range of neonates and the elderly due to congenital and acquired causes. In humans, this is a therapeutic agent that currently regenerates inner ear hair cells. There is no effective treatment because there is no. In addition to the administration of steroids, vasodilators, blood flow improvers, vitamins (B1, B6, B12) and tranquilizers, the anti-peritoneal effect of the antioxidant N-acetylcysteine (Reference 1) There are reports on the combined preventive effect (reference 2) of three antioxidants (β-carotene, vitamin C, vitamin E) and mineral (magnesium) (peritoneal administration, subcutaneous administration, oral administration). Furthermore, there is hyperbaric oxygen therapy for the purpose of improving blood circulation in the inner ear and increasing the partial pressure of oxygen (Reference Document 3). However, none of these existing therapies are limited, and none of them can achieve clinically satisfactory results, and if recovery is not expected, a hearing aid will be used. Ineffective for hearing loss. At the research level, introduction of effective genes using viral vectors (Reference 4) and introduction of neurotrophic factors such as BDNF / GDNF directly into the inner ear (References 5 and 6) have been attempted at the animal level. These methods are all introduced directly into the inner ear, and there are high hurdles toward clinical development. Therefore, once it becomes deaf, it is difficult to treat and there is a need for preventive measures to prevent deafness. However, there are no hearing loss preventives currently used clinically, and the current situation is that they rely on physical shielding such as earplugs. In this study, we focused on the increased expression of Ednrb in the cochlear cap membrane in Ednrb-Tg mice, and showed that these mice are resistant to hearing loss. The promoter used in this study (DbH promoter) is expressed in peripheral nerves and pigment cells derived from the neural crest (Refs. 7 and 8), and therefore, the auditory nerve (peripheral nerve), which is very important for the control of hearing in the inner ear, and A DbH promoter that can act on both vascular intermediate cells (pigment cells) is optimal. In fact, it has been reported that DbH is expressed in the cap membrane in the cochlea (Reference 9), which is consistent with the present data. Furthermore, it was found that a compound that increases the expression of Ednrb was ingested as an aqueous solution, and that this compound similarly exhibited increased expression of Ednrb in the cochlear cap membrane and resistance to noise-induced hearing loss and age-related hearing loss. This compound is a kind of flavonoid and has an anti-inflammatory effect, and when it is ingested by mice as drinking water, it has been reported that IL-6 production by LPS in the cerebellum is suppressed (Reference 10), and even when administered orally, it is sufficiently biological. It was thought that it was effective. Ingestion of drinking water containing a compound that increases the expression of Ednrb causes the same expression pattern as when the gene is forcibly expressed, so the expression of Ednrb is actually enhanced in the inner ear and functions. In addition, it is groundbreaking to be resistant to hearing loss, and it is clinically possible as a method that can be easily applied to the inner ear for hearing loss for which no prophylactic drugs existed. It can be said that this is a very useful method.

<References>
1. Bielefeld EC et al., Noise Health 7 (29): 24-30 (2005)
2. Le Prell CG et al., Free Radic Biol Med 42 (9): 1454-1463 (2007)
3. Conlin AE et al., Arch Otolaryngol Head Neck Surg 133 (6): 573-581 (2007)
4). Izumikawa M et al., Nat Med 11 (3): 271-276 (2005)
5. Altschuler RA et al., Ann NY Acad Sci 884: 305-311 (1999)
6). Maruyama J et al., Neurobiol Dis 29 (1): 14-21 (2008)
7). Kapur RP et al., Development 116 (1): 167-175 (1992)
8). Kapur RP et al., Neuron 7 (5): 717-727 (1991)
9. Trigueiros-Cunha N et al., Eur J Neurosci 18 (9): 2653-2662 (2003)
10. Jang S et al., Proc Natl Acad Sci USA 105 (21): 7534-7539 (2008)

  The prophylactic / therapeutic agent of the present invention is effective in preventing or treating age-related hearing loss, noise-induced hearing loss, or tinnitus. As a usage form, for example, daily / continuous use (ingestion, administration, etc.) by an elderly person is assumed as prevention of age-related deafness. In addition, for prevention of noise-induced hearing loss, in addition to daily / continuous use by noise workers, music players, and other users, those who are placed in a loud acoustic environment (eg concert attendees) One-time (advanced) usage is assumed.

The present invention is not limited to the description of the embodiments and examples of the invention described above. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.
The contents of papers, published patent gazettes, patent gazettes, and the like specified in this specification are incorporated by reference in their entirety.

Claims (2)

A composition for preventing / treating age-related hearing loss or noise-induced hearing loss or tinnitus, comprising luteolin, a substance that increases the expression of endothelin receptor B (excluding food and drink) . It is pharmaceuticals, preventive or therapeutic composition of claim 1.

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