WO2023190707A1 - Composition de prévention ou de traitement de perte d'audition neurosensorielle - Google Patents

Composition de prévention ou de traitement de perte d'audition neurosensorielle Download PDF

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WO2023190707A1
WO2023190707A1 PCT/JP2023/012857 JP2023012857W WO2023190707A1 WO 2023190707 A1 WO2023190707 A1 WO 2023190707A1 JP 2023012857 W JP2023012857 W JP 2023012857W WO 2023190707 A1 WO2023190707 A1 WO 2023190707A1
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moc
hearing loss
neurons
compound
serotonin
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Japanese (ja)
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昌一 島田
誠 近藤
秀典 猪原
和也 大畠
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国立大学法人大阪大学
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    • A—HUMAN NECESSITIES
    • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
    • A23L—FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BY SUBCLASSES A21D OR A23B-A23J; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL
    • A23L2/00—Non-alcoholic beverages; Dry compositions or concentrates therefor; Their preparation
    • A23L2/52—Adding ingredients
    • A—HUMAN NECESSITIES
    • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
    • A23L—FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BY SUBCLASSES A21D OR A23B-A23J; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL
    • A23L33/00—Modifying nutritive qualities of foods; Dietetic products; Preparation or treatment thereof
    • A23L33/10—Modifying nutritive qualities of foods; Dietetic products; Preparation or treatment thereof using additives
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/33—Heterocyclic compounds
    • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
    • A61K31/435—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with one nitrogen as the only ring hetero atom
    • A61K31/44—Non condensed pyridines; Hydrogenated derivatives thereof
    • A61K31/445—Non condensed piperidines, e.g. piperocaine
    • A61K31/4523—Non condensed piperidines, e.g. piperocaine containing further heterocyclic ring systems
    • A61K31/4545—Non condensed piperidines, e.g. piperocaine containing further heterocyclic ring systems containing a six-membered ring with nitrogen as a ring hetero atom, e.g. pipamperone, anabasine
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K45/00—Medicinal preparations containing active ingredients not provided for in groups A61K31/00 - A61K41/00
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P27/00—Drugs for disorders of the senses
    • A61P27/16—Otologicals
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P43/00—Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00

Definitions

  • the present invention relates to the prevention or treatment of hearing impairment.
  • the organ of Corti which is the sensory epithelium in the cochlea, has inner and outer hair cells, and each has afferent nerves going to the center and efferent nerves going from the center to the hair cells.
  • the afferent nerves are divided into spiral nerves type 1 and type 2, both of which project to the cochlear nucleus.
  • one of the efferent nerves is called a MOC (medial olivocochlear) neuron, and the other is called a LOC (lateral olivocochlear) neuron.
  • MOC medial olivocochlear
  • LOC lateral olivocochlear
  • Non-Patent Document 1 The cochlear efferent feedback system conveyed by the olive cochlear pathway plays an important role in auditory processing (Non-Patent Document 1). MOC neurons are central in this neural pathway (Non-Patent Documents 2, 3), and the efferent feedback system via MOC neurons is called the MOC feedback system.
  • the MOC feedback system adjusts the dynamic range of hearing (Non-patent Document 4), has the function of protecting against acoustic trauma (Non-patent Documents 5, 6), and mediates signal detection in noisy environments (Non-patent Documents 7). However, the cellular and molecular mechanisms of the MOC feedback system are not completely understood.
  • the serotonin 3 (5-HT3) receptor is the only ionotropic receptor in the serotonin receptor family (Non-Patent Document 8).
  • the 5-HT3 receptor consists of two subunits (5-HT3A and 5-HT3B), and the 5-HT3A subunit is essential for the formation of a functional receptor (Non-Patent Document 8). It has been suggested that 5-HT3A receptors are widely expressed in the central and peripheral nervous systems and are related to various important neurological functions (Non-Patent Document 9). In a previous study, the present inventors reported that 5-HT3A receptors are expressed in the superior olivary complex (SOC) of the brainstem, where MOC neurons and LOC neurons are located (Non-patent Document 10 ). However, the relationship between the MOC feedback system and 5-HT3 receptors is unknown.
  • SOC superior olivary complex
  • Acoustic trauma is damage to the auditory system in which the cochlea of the inner ear is damaged by powerful sound waves. Symptoms include hearing loss and tinnitus.
  • Chronic acoustic trauma also called noise-induced hearing loss, occurs when people are exposed to high-intensity noise in the environment for long periods of time.
  • Chronic acoustic trauma (noise-induced hearing loss) progresses gradually and has few symptoms.
  • Acute acoustic trauma includes hearing loss caused by instantaneous or extremely short-lived loud noises caused by explosions, firearms, airbags, etc., and hearing loss caused by exposure to loud noises from headphones, concerts, etc. over a period of several minutes to several hours. Includes disability.
  • SR57227A (1-(6-chloropyridin-2-yl)piperidin-4-amine or its hydrochloride) is known (Patent Document 1).
  • Brown MC de Venecia RK, Guinan JJ Jr. Exp Brain Res. 2003;153:491-498. Brown MC, Levine JL. Neuroscience. 2008;154:147-159. Guinan JJ Jr, Stankovic KM. J Acoust Soc Am. 1996;100:1680-1690. Rajan R. J Neurosci. 2000;20:6684-6693. Taranda J, Maison SF, Ballestero JA, et al. PLoS Biol. 2009;7:e18. Winslow RL, Sachs MB. Hear Res. 1988;35:165-189. Barnes NM, Sharp T. Neuropharmacology. 1999;38:1083-1152. Morales M, Wang SD. J Neurosci. 2002;22:6732-6741. Koyama Y, Kondo M, Shimada S. Sci Rep. 2017;7:42884.
  • the present invention aims to elucidate the mechanism of the MOC feedback system, provide compositions for preventing or treating hearing disorders involving MOC neurons, and compounds for preventing or treating hearing disorders involving MOC neurons.
  • the objective is to provide a screening method for
  • the present inventors discovered that serotonin 3 receptors (hereinafter also referred to as 5-HT3 receptors) have a fundamental role in the MOC feedback system, and that 5-HT3 receptors have a fundamental role in the MOC feedback system.
  • the inventors have discovered that a body agonist can solve the above problems, and have completed the present invention. That is, the present invention includes the following aspects. 1. A composition for preventing or treating sensorineural hearing loss containing a serotonin 3 receptor agonist. 2. 2. The composition according to item 1, wherein the sensorineural hearing loss is acoustic trauma or age-related hearing loss. 3.
  • the symptoms of acoustic trauma or age-related hearing loss include hearing loss, insufficient speech discrimination in a noisy environment even with normal hearing, and insufficient speech discrimination in a noisy environment accompanied by hearing loss.
  • the composition according to item 2 above, wherein the composition has at least one selected from the group consisting of: 4. 2.
  • the serotonin 3 receptor agonist has the following formula (I): [In the formula, m is an integer from 1 to 4; R 1 is a hydrogen atom, a halogen atom, a methyl group optionally substituted with 1 to 3 halogen atoms, a methoxy group optionally substituted with 1 to 3 halogen atoms, 1 to 3 halogen atoms an ethoxy group which may be substituted with , a methylthio group which may be substituted with 1 to 3 halogen atoms, and a halogen atom, trifluoromethyl, C 1-3 alkyl, C 1-3 alkoxy, C 1 -3 phenoxy groups optionally substituted with alkylthio or cyano groups, each independently selected from the group consisting of The composition according to any one of items 1 to 4 above, which is a compound represented by or a pharmaceutically acceptable salt thereof.
  • each R 1 is independently a halogen atom. 7.
  • the composition according to item 6, wherein the halogen atom is a chlorine atom. 8.
  • a method for screening a compound for prevention or treatment of sensorineural hearing loss comprising the step of measuring serotonin 3 receptor agonist activity.
  • a method for screening MOC neuron activating compounds comprising the step of measuring serotonin 3 receptor agonist activity. 13.
  • a method of preventing or treating sensorineural hearing loss comprising administering a composition containing a serotonin 3 receptor agonist to a subject in need thereof.
  • a method of activating MOC neurons comprising administering a composition containing a serotonin 3 receptor agonist to a subject in need thereof.
  • a method for preventing or treating hearing impairment involving MOC neurons the method comprising administering a composition containing a serotonin 3 receptor agonist to a subject in need thereof.
  • Use of a serotonin-3 receptor agonist for the preparation of a composition for the prevention or treatment of sensorineural hearing loss.
  • 5-HT3 receptor agonists can activate MOC neurons and enhance or improve the function of the MOC feedback system via MOC neurons.
  • 5-HT3 receptors have a fundamental role in the MOC feedback system.
  • Sensorineural hearing loss which is a hearing impairment or auditory condition involving impaired or inadequate functioning of MOC neurons, can be prevented or treated with 5-HT3 receptor agonists.
  • the MOC feedback system is a system that responds in real time to sounds that are too loud or difficult to hear by regulating the movement of outer hair cells and controlling the amplitude of the basilar membrane through its efferent neurons.
  • One of the functions of the MOC feedback system is to protect the cochlea by suppressing the vibration of the basilar membrane in response to strong loud sounds and suppressing damage to hair cells and the like. Enhancement of MOC neuron activity via 5-HT3 receptors by 5-HT3 receptor agonists enhances cochlear protection and enables the prevention and treatment of hearing loss caused by exposure to high-intensity sounds.
  • One of the other functions of the MOC feedback system is the ability to amplify and suppress basilar membrane vibrations that correspond to specific frequencies.
  • the vibration of the basilar membrane is amplified, and when talking in noise, the vibration of the basilar membrane corresponding to the frequency range of the human voice is amplified, and the vibration of the basilar membrane is amplified to correspond to the frequency range of the surrounding noise. Suppresses the vibration of the basement membrane. Enhancement of MOC neuron activity via 5-HT3 receptors by 5-HT3 receptor agonists enables the prevention and treatment of hearing disorders such as age-related hearing loss and insufficient speech discrimination ability in noisy environments. .
  • FIG. 1 shows that serotonin 3 receptors are expressed on MOC neurons that project to the cochlea.
  • A Coronal section of mouse brainstem stained with hematoxylin-eosin is shown.
  • B shows a coronal section of the brainstem of a 5-HT3AR-EGFP transgenic reporter mouse stained with enhanced green fluorescent protein (EGFP).
  • C Coronal section of the brainstem of a wild-type mouse after intratympanic injection of Fluoro-GoldTM (hereinafter also referred to as FG). Left: Ipsilateral; Right: Contralateral.
  • D Coronal section of the brainstem of a 5-HT3AR-EGFP transgenic reporter mouse after intratympanic FG injection is shown.
  • FIG. 1 shows the results of immunohistochemical analysis of the cochlea of a 5-HT3AR-EGFP transgenic reporter mouse, showing the distribution of efferent fibers of 5-HT3 receptor-expressing MOC neurons in the cochlea.
  • A Immunostaining for GFP and ChAT (choline acetyltransferase) and DAPI counterstaining in the basal, middle, and apical regions of a cochlear whole-mount specimen.
  • B Immunostaining for GFP and ChAT and DAPI counterstaining of cochlear sections is shown. Arrowheads indicate EGFP signals on nerve fibers traversing the tunnel of Corti, and arrows indicate EGFP signals below OHCs (outer hair cells).
  • GFP Green
  • ChAT Red
  • DAPI Blue, but all are shown in gray in gray scale. Scale bars indicate 10 ⁇ m (A) and 20 ⁇ m (B). At least three independent experiments showed similar results.
  • FIG. 3 shows that 5-HT3 receptors are involved in the activation of MOC neurons by exposure to high-intensity sound.
  • A Shows c-Fos immunostaining of a coronal section of the brainstem of a wild type mouse before exposure to high-intensity sound.
  • B Immunostaining of c-Fos in the coronal section of the brainstem of a wild-type mouse injected with FG intratympanically 1 h after exposure to high-intensity sound. Arrows indicate c-Fos positive neurons labeled by FG. Top: low magnification; bottom: high magnification.
  • FIG. 4 shows that Htr3a ⁇ / ⁇ mice had impaired MOC function and hearing loss was exacerbated by exposure to loud sounds.
  • Figure 5 shows the results of immunohistochemical analysis of the organ of Corti in wild-type (WT) mice and Htr3a ⁇ / ⁇ (KO) mice before, 7 days after, and 14 days after exposure to high-intensity noise.
  • C-terminal-binding protein 2 (CtBP2) was used as a presynaptic marker of ribbon synapses, and GluA2 was used as a postsynaptic marker.
  • IHC inner hair cells
  • CtBP2-positive points are shown in green and GluA2-positive points are shown in red.
  • CtBP2-positive points are shown in white and GluA2-positive points are shown in gray. It is indicated by.
  • A Immunostaining of CtBP2 and GluA2 in the cochlea. Arrows indicate parallel CtBP2/GluA2 positive points in IHC. The scale bar indicates 10 ⁇ m.
  • FIG. 1 Shows the results of immunohistochemical analysis of CtBP2 and GluA2 in IHC of wild type (WT) and Htr3a ⁇ / ⁇ (KO) mice before, 1 hour, 24 hours, and 7 days after exposure to high-intensity sound. .
  • the scale bar indicates 5 ⁇ m.
  • the dotted line indicates the approximate outline of the IHC.
  • Figure 7 shows that in Htr3a ⁇ / ⁇ mice, high-intensity sound causes loss of many inner hair cell (IHC) ribbon synapses in the cochlear base region.
  • IHC inner hair cell
  • FIG. 8 shows that in Htr3a ⁇ / ⁇ mice, high-intensity sound causes loss of many inner hair cell (IHC) ribbon synapses in the midcochlear region.
  • IHC inner hair cell
  • FIG. 10 shows that 5-HT3 receptor agonists attenuate loud sound-induced hearing loss.
  • a and (B) show cochlear function 7 days after exposure to high-intensity sound.
  • Physiological saline (Sal) or SR57227A (Ag) was administered to mice 30 minutes before exposure to high-intensity sound.
  • FIG. 11 shows that 5-HT3 receptor agonists attenuate loud sound-induced loss of ribbon synapses.
  • mice were administered physiological saline (Sal), SR57227A (Ag), or ondansetron (Ant) 30 minutes before loud sound exposure.
  • IHC inner hair cells; NE: loud sound exposure (+: with exposure, -: without exposure) All graphs are shown as mean ⁇ standard error. * P ⁇ 0.05, ** P ⁇ 0.01, *** P ⁇ 0.001; ns (not significant), one-way ANOVA, followed by Tukey's multiple comparison test
  • the serotonin 3 receptor agonist which is the active ingredient of the composition of the present invention, is a substance that exerts a similar effect to serotonin on the serotonin 3 receptor, and is not limited thereto.
  • Suitable compounds for the serotonin 3 receptor agonist which is an active ingredient of the composition of the present invention, include any one of the following formulas (I), (II), (III), (IV), (V) or (VI). Mention may be made of the indicated compounds or their pharmaceutically acceptable salts, or their hydrates or solvates.
  • the number of carbon atoms in the definition of “substituent” may be expressed as “C 1-3 ", “C 1-6 ", etc., for example.
  • the notation “C 1-3 alkyl” is synonymous with a linear or branched alkyl group having 1 to 3 carbon atoms
  • the notation “C 1-6 alkyl” has the same meaning as a straight-chain or branched alkyl group having 1 to 3 carbon atoms. It has the same meaning as 1 to 6 linear or branched alkyl groups.
  • group means a monovalent group.
  • alkyl group means a monovalent saturated hydrocarbon group.
  • group may be omitted.
  • description of each group also applies when the group is a part or substituent of another group.
  • halogen atom examples include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention has the following formula (I): [In the formula, m is an integer from 1 to 4; R 1 is a hydrogen atom, a halogen atom, a methyl group optionally substituted with 1 to 3 halogen atoms, a methoxy group optionally substituted with 1 to 3 halogen atoms, 1 to 3 halogen atoms an ethoxy group which may be substituted with , a methylthio group which may be substituted with 1 to 3 halogen atoms, and a halogen atom, trifluoromethyl, C 1-3 alkyl, C 1-3 alkoxy, C 1 -3 phenoxy groups optionally substituted with alkylthio or cyano groups, each independently selected from the group consisting of or a pharmaceutically acceptable salt thereof.
  • R 1 is a hydrogen atom, a halogen atom, a methyl group optionally substituted with 1 to 3 halogen atoms
  • n is an integer of 1 to 4, preferably an integer of 1 to 3, more preferably an integer of 1 to 2, particularly preferably 1.
  • the halogen atom in R 1 is preferably a fluorine atom or a chlorine atom, with a chlorine atom being particularly preferred.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 1 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, and methyl groups and trifluoromethyl groups are particularly preferred. preferable.
  • the methoxy group optionally substituted with 1 to 3 halogen atoms in R 1 is preferably a methoxy group optionally substituted with 1 to 3 fluorine atoms, and methoxy groups and trifluoromethoxy groups are particularly preferred. preferable.
  • the ethoxy group optionally substituted with 1 to 3 halogen atoms in R 1 is preferably an ethoxy group optionally substituted with 1 to 3 fluorine atoms, and ethoxy groups and 2,2,2- Particularly preferred is trifluoroethoxy group.
  • the methylthio group optionally substituted with 1 to 3 halogen atoms in R 1 is preferably a methylthio group optionally substituted with 1 to 3 fluorine atoms, with methylthio groups and trifluoromethylthio groups being particularly preferred. preferable.
  • R 1 can be a phenoxy group optionally substituted with a halogen atom, trifluoromethyl, C 1-3 alkyl, C 1-3 alkoxy, C 1-3 alkylthio or cyano group.
  • C 1-3 alkyl residues of saturated aliphatic hydrocarbons having 1, 2 or 3 carbon atoms (methyl, ethyl, propyl, isopropyl, etc. )including.
  • each R 1 is independently a halogen atom, more preferably each R 1 is a chlorine atom.
  • n is 1. In a more preferred embodiment, R 1 is a halogen atom and m is 1.
  • the compound of formula (I) or a pharmaceutically acceptable salt thereof has the following formula (I'): [In the formula, R 1 has the same meaning as above] or a pharmaceutically acceptable salt thereof.
  • the compound of formula (I) or a pharmaceutically acceptable salt thereof is of the following formula: (Compound name: 1-(6-chloropyridin-2-yl)piperidin-4-amine; hereinafter also referred to as "Compound A”) or a pharmaceutically acceptable salt thereof.
  • Compound A particularly preferred is SR57227A (compound A or its hydrochloride).
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention has the following formula (II): [In the formula, n is an integer from 1 to 4; R 2 is a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, a methyl group optionally substituted with 1 to 3 halogen atoms, a methoxy group optionally substituted with 1 to 3 halogen atoms, and each independently selected from the group consisting of methylthio groups optionally substituted with 1 to 3 halogen atoms] or a pharmaceutically acceptable salt thereof.
  • formula (II) [In the formula, n is an integer from 1 to 4; R 2 is a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, a methyl group optionally substituted with 1 to 3 halogen atoms, a methoxy group optionally substituted with 1 to 3 halogen atoms, and each independently selected from the group consisting
  • n is an integer of 1 to 4, preferably an integer of 1 to 3, more preferably an integer of 1 to 2, particularly preferably 1.
  • the halogen atom in R 2 is preferably a fluorine atom or a chlorine atom, with a chlorine atom being particularly preferred.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 2 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, and methyl groups and trifluoromethyl groups are particularly preferred. preferable.
  • the methoxy group optionally substituted with 1 to 3 halogen atoms in R 2 is preferably a methoxy group optionally substituted with 1 to 3 fluorine atoms, and methoxy groups and trifluoromethoxy groups are particularly preferred. preferable.
  • the methylthio group optionally substituted with 1 to 3 halogen atoms in R 2 is preferably a methylthio group optionally substituted with 1 to 3 fluorine atoms, with methylthio groups and trifluoromethylthio groups being particularly preferred. preferable.
  • each R 2 is independently a hydrogen atom or a halogen atom, preferably each R 2 is independently a hydrogen atom or a chlorine atom.
  • n is 1.
  • R 2 is a hydrogen atom or a halogen atom and n is 1.
  • the compound of formula (II) or a pharmaceutically acceptable salt thereof is of formula (II'): [In the formula, R 2 has the same meaning as above] or a pharmaceutically acceptable salt thereof.
  • the compound of formula (II) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: m-chlorophenyl biguanide; hereinafter also referred to as "Compound B”) or a pharmaceutically acceptable salt thereof, and particularly preferably the hydrochloride of Compound B.
  • the compound of formula (II) or a pharmaceutically acceptable salt thereof has the following formula:
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention has the following formula (III): [In the formula, o is an integer from 1 to 4; R 3 is a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, a methyl group optionally substituted with 1 to 3 halogen atoms, a methoxy group optionally substituted with 1 to 3 halogen atoms, and each independently selected from the group consisting of methylthio groups optionally substituted with 1 to 3 halogen atoms; R 4 is selected from the group consisting of a hydrogen atom and a methyl group optionally substituted with 1 to 3 halogen atoms] or a pharmaceutically acceptable salt thereof.
  • o is an integer of 1 to 4, preferably an integer of 1 to 3, more preferably an integer of 1 to 2, particularly preferably 1.
  • the halogen atom in R 3 is preferably a fluorine atom or a chlorine atom, with a chlorine atom being particularly preferred.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 3 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, with methyl groups and trifluoromethyl groups being particularly preferred. preferable.
  • the methoxy group optionally substituted with 1 to 3 halogen atoms in R 3 is preferably a methoxy group optionally substituted with 1 to 3 fluorine atoms, and methoxy groups and trifluoromethoxy groups are particularly preferred. preferable.
  • the methylthio group optionally substituted with 1 to 3 halogen atoms in R 3 is preferably a methylthio group optionally substituted with 1 to 3 fluorine atoms, and methylthio and trifluoromethylthio groups are particularly preferred. preferable.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 4 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, particularly preferably a methyl group.
  • each R 3 is independently a hydrogen atom or a halogen atom, preferably each R 3 is independently a hydrogen atom or a chlorine atom.
  • R 4 is a hydrogen atom or a methyl group.
  • o is 1.
  • R 3 is a hydrogen atom or a halogen atom
  • R 4 is a hydrogen atom or a methyl group
  • o is 1.
  • the compound represented by formula (III) or a pharmaceutically acceptable salt thereof is represented by the following formula (III'): [In the formula, R 4 has the same meaning as above] or a pharmaceutically acceptable salt thereof.
  • the compound represented by formula (III) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: N-methylquipazine; hereinafter also referred to as "Compound D”) or a pharmaceutically acceptable salt thereof, and particularly preferred is the dimaleate of Compound D.
  • the compound represented by formula (III) or a pharmaceutically acceptable salt thereof has the following formula:
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention has the following formula (IV): [In the formula, p is an integer from 1 to 4; R 5 and R 6 are hydrogen atom, halogen atom, hydroxy group, cyano group, methyl group optionally substituted with 1 to 3 halogen atoms, methoxy optionally substituted with 1 to 3 halogen atoms and methylthio optionally substituted with 1 to 3 halogen atoms; R 7 is selected from the group consisting of a hydrogen atom and a methyl group optionally substituted with 1 to 3 halogen atoms] or a pharmaceutically acceptable salt thereof.
  • p is an integer of 1 to 4, preferably an integer of 1 to 3, more preferably an integer of 1 to 2, particularly preferably 1.
  • halogen atom in R 5 and R 6 a fluorine atom and a chlorine atom are preferred, and a chlorine atom is particularly preferred.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 5 and R 6 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, and methyl groups and trifluoromethyl Particularly preferred are groups.
  • the methoxy group optionally substituted with 1 to 3 halogen atoms in R 5 and R 6 is preferably a methoxy group optionally substituted with 1 to 3 fluorine atoms, and methoxy groups and trifluoromethoxy Particularly preferred are groups.
  • the methylthio group optionally substituted with 1 to 3 halogen atoms in R 5 and R 6 is preferably a methylthio group optionally substituted with 1 to 3 fluorine atoms, and methylthio group and trifluoromethylthio group are preferred. Particularly preferred are groups.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 7 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, particularly preferably a methyl group.
  • each R 5 is independently selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, and a cyano group, and preferably each R 5 is a hydroxy group.
  • R 6 is selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, and a methyl group optionally substituted with 1 to 3 halogen atoms, preferably a methyl group. be.
  • R 7 is a hydrogen atom or a methyl group, preferably a hydrogen atom.
  • R 5 is selected from the group consisting of halogen atoms, hydroxy groups, and cyano groups
  • R 6 is hydrogen atoms, halogen atoms, and methyl optionally substituted with 1 to 3 halogen atoms
  • R 7 is a hydrogen atom or a methyl group, and p is 1.
  • the compound of formula (IV) or a pharmaceutically acceptable salt thereof is of formula (IV'): [In the formula, R 5 , R 6 and R 7 have the same meanings as above] or a pharmaceutically acceptable salt thereof.
  • the compound of formula (IV) or a pharmaceutically acceptable salt thereof has the following formula:
  • the compound represented by compound name: 2-methyl-5-hydroxytryptamine; hereinafter also referred to as "compound F” or a pharmaceutically acceptable salt thereof, particularly preferably the hydrochloride of compound F.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention has the following formula (V): [In the formula, q is an integer from 1 to 4; R 8 and R 9 are hydrogen atom, halogen atom, hydroxy group, cyano group, methyl group optionally substituted with 1 to 3 halogen atoms, methoxy optionally substituted with 1 to 3 halogen atoms and methylthio optionally substituted with 1 to 3 halogen atoms; R 10 is selected from the group consisting of a hydrogen atom and a methyl group optionally substituted with 1 to 3 halogen atoms] or a pharmaceutically acceptable salt thereof.
  • q is an integer of 1 to 4, preferably an integer of 1 to 3, more preferably an integer of 1 to 2, particularly preferably 1.
  • halogen atom in R 8 and R 9 a fluorine atom and a chlorine atom are preferred, and a chlorine atom is particularly preferred.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 8 and R 9 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, and methyl groups and trifluoromethyl Particularly preferred are groups.
  • the methoxy group optionally substituted with 1 to 3 halogen atoms in R 8 and R 9 is preferably a methoxy group optionally substituted with 1 to 3 fluorine atoms, and methoxy groups and trifluoromethoxy Particularly preferred are groups.
  • the methylthio group optionally substituted with 1 to 3 halogen atoms in R 8 and R 9 is preferably a methylthio group optionally substituted with 1 to 3 fluorine atoms, and methylthio group and trifluoromethylthio group are preferred. Particularly preferred are groups.
  • the methyl group optionally substituted with 1 to 3 halogen atoms in R 10 is preferably a methyl group optionally substituted with 1 to 3 fluorine atoms, particularly preferably a methyl group.
  • each R 8 is independently selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, and a cyano group, and preferably each R 8 is a hydrogen atom.
  • R 9 is selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, and a methyl group optionally substituted with 1 to 3 halogen atoms, preferably a hydrogen atom. be.
  • R 10 is a hydrogen atom or a methyl group, preferably a methyl group.
  • q is 1.
  • R 8 is a hydrogen atom or a hydroxy group
  • R 9 is a hydrogen atom or a methyl group
  • R 10 is a hydrogen atom or a methyl group
  • q is 1.
  • the compound represented by formula (V) or a pharmaceutically acceptable salt thereof has the following formula (V'): [In the formula, R 8 , R 9 , and R 10 have the same meanings as above] or a pharmaceutically acceptable salt thereof.
  • the compound of formula (V) or a pharmaceutically acceptable salt thereof has the following formula:
  • the active ingredient of the present invention has the following formula (VI):
  • Q is the following formula (a) to (c):
  • R 11 represents a hydrogen atom or a C 1-6 alkyl group
  • R 12 and R 13 are the same or different and represent a hydrogen atom or a C 1-6 alkyl group; Alternatively, they may be combined with the carbon atoms to which they are bonded to form a 3- to 8-membered cycloalkane ring
  • R 14 and R 15 are the same or different and represent a hydrogen atom or a C 1-6 alkyl group; Alternatively, they may be combined with the nitrogen atom to which they are bonded to form a 3- to 8-membered cyclic amine
  • n represents 0, 1, 2, 3, 4, or 5
  • R 14 and R 15 are both hydrogen atoms
  • R 12 represents a group represented by any one of C 2-6 alkyl group] or a pharmaceutically acceptable salt thereof.
  • Q is a group of formula (a) or (b). More preferably, Q is a group represented by formula (a).
  • n 1, 2 or 3.
  • R 12 is a hydrogen atom.
  • R 13 is a hydrogen atom or a C 1-6 alkyl group. More preferably, R 12 is a hydrogen atom, and R 13 is a hydrogen atom or a C 1-6 alkyl group.
  • R 14 is a hydrogen atom or a C 1-6 alkyl group.
  • R 15 is a C 1-6 alkyl group. More preferably, R 14 is a hydrogen atom or a C 1-6 alkyl group, and R 15 is a C 1-6 alkyl group.
  • R 11 is a hydrogen atom.
  • R 11 and R 12 are hydrogen atoms.
  • R 11 is a hydrogen atom, and R 13 is a hydrogen atom or a C 1-6 alkyl group. More preferably, R 11 and R 12 are hydrogen atoms, and R 13 is a hydrogen atom or a C 1-6 alkyl group.
  • R 11 is a hydrogen atom
  • R 14 is a hydrogen atom or a C 1-6 alkyl group.
  • R 11 is a hydrogen atom and R 15 is a C 1-6 alkyl group. More preferably, R 11 is a hydrogen atom, R 14 is a hydrogen atom or a C 1-6 alkyl group, and R 15 is a C 1-6 alkyl group.
  • C 1-6 alkyl group means a linear or branched saturated hydrocarbon group having 1 to 6 carbon atoms. Preferably it is a "C 1-4 alkyl group”. Specific examples of “C 1-6 alkyl group” include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, 1-ethylpropyl, hexyl, isohexyl , 1,1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 2-ethylbutyl and the like.
  • Examples of the "cycloalkane ring" in which R 12 and R 13 "may form a 3- to 8-membered cycloalkane ring together with the carbon atom to which they are bonded” include, for example, cyclopropane. ring, cyclobutane ring, cyclopentane ring, cyclohexane ring, cycloheptane ring, cyclooctane ring, etc.
  • 3- to 8-membered cyclic amine means a 3- to 8-membered saturated or unsaturated cyclic amine.
  • Examples of the "cyclic amine” in which R 14 and R 15 "may form a 3- to 8-membered cyclic amine together with the nitrogen atom to which they are bonded” include, for example, an aziridine ring, an azetidine ring, pyrrolidine ring, piperidine ring, azepane ring, azocane ring and the like.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: (2-aminophenyl)(azetidin-3-yl)methanone; hereinafter also referred to as "compound H”) or a pharmaceutically acceptable salt thereof.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: 1-(2-aminophenyl)-3-(methylamino)propan-1-one; hereinafter also referred to as "Compound I”) or a pharmaceutically acceptable salt thereof. Particularly preferred is the hydrochloride of compound I.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: (2-aminophenyl)(pyrrolidin-3-yl)methanone; hereinafter also referred to as "Compound J”) or a pharmaceutically acceptable salt thereof. Particularly preferred is the hydrochloride of Compound J.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: (2-aminophenyl)(piperidin-3-yl)methanone; hereinafter also referred to as "compound K”) or a pharmaceutically acceptable salt thereof.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: 1-(2-aminophenyl)-2-(pyrrolidin-2-yl)ethanone; hereinafter also referred to as "Compound L”) or a pharmaceutically acceptable salt thereof. Particularly preferred is the hydrochloride of compound L.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: 1-(2-aminophenyl)-3-(methylamino)butan-1-one; hereinafter also referred to as "compound M”) or a pharmaceutically acceptable salt thereof.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: 3-amino-1-(2-aminophenyl)butan-1-one; hereinafter also referred to as "compound N”) or a pharmaceutically acceptable salt thereof.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: (-)-(2-aminophenyl)(pyrrolidin-3-yl)methanone; hereinafter also referred to as "compound O”) or a pharmaceutically acceptable salt thereof. Particularly preferred is the hydrochloride of compound O.
  • the compound of formula (VI) or a pharmaceutically acceptable salt thereof has the following formula: (Compound name: (+)-(2-aminophenyl)(pyrrolidin-3-yl)methanone; hereinafter also referred to as "compound P”) or a pharmaceutically acceptable salt thereof. Particularly preferred is the hydrochloride of compound P.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention is represented by any of formulas (I), (II), (III), (IV), (V) or (VI). compound or a pharmaceutically acceptable salt thereof.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention is a compound represented by any one of formula (I), (II), (IV), (V) or (VI) or a pharmaceutical thereof. It is an acceptable salt.
  • the active ingredient of the present invention, a serotonin 3 receptor agonist has the formula (I'), (II'), (III'), (IV'), or (V'). The indicated compound or a pharmaceutically acceptable salt thereof.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention is a compound represented by any of formulas (I'), (II'), (IV'), or (V') or its It is a pharmaceutically acceptable salt.
  • the active ingredient of the present invention, a serotonin 3 receptor agonist is a compound A, B, C, D, E, F, G, H, I, J, K, L, M, N, O or P or a pharmaceutically acceptable salt thereof.
  • the active ingredient of the present invention is a compound A, B, C, F, G, H, I, J, K, L, M, N, O or P or its It is a pharmaceutically acceptable salt.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention is a compound represented by formula (I) or a pharmaceutically acceptable salt thereof.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention is a compound represented by formula (I') or a pharmaceutically acceptable salt thereof.
  • the serotonin 3 receptor agonist that is the active ingredient of the present invention is Compound A or a pharmaceutically acceptable salt thereof.
  • the serotonin 3 receptor agonist which is an active ingredient of the present invention, such as a compound represented by any of formulas (I), (II), (III), (IV), (V) or (VI), can be used in free form. However, it may also be in the form of a pharmaceutically acceptable salt.
  • salts include, for example, hydrochloride, hydrobromide, hydroiodide, sulfate, nitrate, phosphate, formate, acetate, propionate, fumarate, Oxalate, malonate, succinate, methanesulfonate, ethanesulfonate, benzenesulfonate, toluenesulfonate, maleate, dimaleate, lactate, malate, tartrate , acid addition salts such as citrate, pamoate and trifluoroacetate; metal salts such as lithium, potassium, calcium, magnesium, sodium, zinc and aluminum salts; and ammonium salts, diethanolamine. salts, base addition salts such as ethylenediamine salts, triethanolamine salts, and triethylamine salts.
  • the serotonin 3 receptor agonist which is the active ingredient of the present invention, such as a compound represented by any one of formulas (I), (II), (III), (IV), (V) or (VI) or its pharmaceutical Acceptable salts include any of their internal salts, adducts, solvates or hydrates, co-crystals, and the like.
  • the serotonin 3 receptor agonist which is the active ingredient of the present invention, for example, a compound represented by formula (I), (II), (III), (IV), (V) or (VI), has a When it has an asymmetric carbon atom, it may exist as a plurality of stereoisomers (i.e., diastereoisomers, optical isomers) based on the asymmetric carbon atom, and the active ingredient of the present invention does not contain any of these stereoisomers. It includes both stereoisomers and mixtures thereof.
  • the serotonin 3 receptor agonist which is the active ingredient of the present invention, such as a compound represented by any one of formulas (I), (II), (III), (IV), (V) or (VI), may be
  • the isomers may include cis and trans isomers, and if the molecule has axial asymmetry, it may include isomers based on axial asymmetry, and any one of these isomers or its Both include mixtures.
  • the serotonin 3 receptor agonist which is the active ingredient of the present invention, for example, a compound represented by any one of formulas (I), (II), (III), (IV), (V) or (VI), is an isotope (for example, compounds labeled with 2 H, 3 H, 13 C, 14 C, 15 N, 18 F, 32 P, 35 S, 125 I, etc.) and deuterium converters are included.
  • the invention also includes prodrugs of the compounds of the invention or pharmaceutically acceptable salts thereof.
  • the prodrugs are functional derivatives of the compounds of the invention that can be easily converted in vivo to the required compound.
  • MOC (medial olivocochlear) neurons are nerve cells that project from the superior olivary nucleus of the brain stem to the cochlea.
  • activating MOC neurons means increasing the neural activity of MOC neurons by stimulating the 5-HT3 receptors expressed in MOC neurons with its agonist.
  • the cochlear efferent feedback system conveyed by the olivocochlear pathway plays an important role in auditory processing.
  • MOC neurons, which project to the cochlea from the superior olivary nucleus of the brainstem have a central role in the cochlear efferent feedback system.
  • the efferent feedback system via MOC neurons is called the MOC feedback system.
  • Neural activity of MOC neurons includes adjustment of the dynamic range of hearing, protection from acoustic trauma, and signal detection in a noisy environment, and MOC neuron activation includes activation of these neural activities. It will be done.
  • MOC feedback system In the process of sound conveying information to the brain, there are two main functions of the MOC feedback system via MOC neurons.
  • One of its functions is to suppress the vibration of the basement membrane so that hair cells and the like are not damaged due to the excessive vibration of the basement membrane in response to strong and loud noises.
  • Another function is to amplify and suppress vibrations of the basement membrane that correspond to specific frequencies. For example, for conversation, the vibrations of the basilar membrane that correspond to the frequency range of the human voice are amplified, and the vibrations of the basilar membrane that correspond to the frequency range of noise such as the sounds of surrounding cars are suppressed.
  • a hearing disorder involving MOC neurons is a disorder due to decreased or insufficient function of the MOC feedback system via MOC neurons.
  • Hearing disorders involving MOC neurons include sensorineural hearing loss due to acoustic trauma, aging, etc.
  • Sensorineural hearing loss includes hearing loss, insufficient speech discrimination ability in a noisy environment even if hearing is normal, insufficient speech discrimination ability in a noisy environment accompanied by hearing loss, tinnitus, hyperacusis, etc. included.
  • the compositions of the present invention enable the prevention or treatment of sensorineural hearing loss, acoustic trauma, age-related hearing loss, and poor speech discrimination ability in a noisy environment even when hearing is normal. It can be suitably used.
  • hearing loss is a state in which hearing ability is inferior to normal, and a state in which the hearing threshold is increased. Hearing is considered normal if the average hearing level is less than 25 dB.
  • Conductive hearing loss caused by damage to the middle ear is caused by chronic otitis media, ossicular malformation, and the like, and these hearing losses can be treated by surgery or the like.
  • sensorineural hearing loss caused by damage to the inner ear is caused by noise, aging, etc., and treatment is symptomatic and a complete cure is difficult.
  • Hearing disorders due to decreased or insufficient function of the MOC feedback system via MOC neurons include sensorineural hearing loss caused by damage to the inner ear.
  • compositions of the invention allow prevention or treatment of sensorineural hearing loss.
  • Sensorineural hearing loss is hearing loss caused by damage to the inner ear.
  • Sensorineural hearing loss includes acoustic trauma, age-related hearing loss, etc.
  • Symptoms include hearing loss, insufficient speech discrimination ability in a noisy environment even with normal hearing ability, insufficient speech discrimination ability in a noisy environment accompanied by hearing loss, tinnitus, and hyperacusis. These symptoms are largely related to decreased or insufficient function of the MOC feedback system mediated by MOC neurons.
  • compositions of the invention enable the prevention or treatment of acoustic trauma.
  • Acoustic trauma is a disease that causes sensorineural hearing loss due to exposure to powerful sounds.
  • Acoustic trauma in the present invention includes chronic acoustic trauma and acute acoustic trauma.
  • Chronic acoustic trauma is also called noise-induced hearing loss.
  • Symptoms of acoustic trauma include hearing loss, poor speech discrimination in noisy environments, tinnitus, and hyperacusis.
  • Acoustic trauma (hearing loss due to exposure to loud noises) includes noise-induced hearing loss, hearing loss due to audio equipment such as headphones and earphones, hearing loss due to concerts and live performances, and hearing loss due to explosion sounds, etc.
  • the composition of the present invention can be suitably used for the prevention and treatment of hearing loss due to exposure to loud sounds, that is, hearing loss due to acoustic trauma.
  • compositions of the invention enable the prevention or treatment of age-related hearing loss.
  • Symptoms of age-related hearing loss include hearing loss, insufficient speech discrimination ability in noisy environments, inability to hear small sounds and loud and unpleasant sounds (narrow dynamic range), tinnitus, and hyperacusis. Symptoms included. Furthermore, even in cases where hearing ability has not deteriorated significantly, the ability to discriminate speech in a noisy environment is often impaired.
  • the composition of the present invention can be suitably used for the prevention or treatment of hearing loss due to age-related hearing loss.
  • the composition of the present invention can be suitably used for the prevention or treatment of insufficient speech discrimination ability in a noisy environment even when hearing is normal due to age-related hearing loss.
  • the composition of the present invention can be suitably used for the prevention or treatment of insufficient speech discrimination ability in a noisy environment accompanied by hearing loss due to age-related hearing loss.
  • insufficient speech discrimination ability in a noisy environment refers to symptoms such as not being able to understand conversations well in noise, or being unable to understand the content although hearing voices, and in cases where there is no hearing loss ( cases with normal hearing) and cases with hearing loss.
  • the MOC feedback system via MOC neurons has the function of amplifying the vibrations of the basilar membrane corresponding to the frequency range of human voices for conversation, and suppressing the vibrations of the basilar membrane corresponding to the frequency range of noise such as the sound of surrounding cars. Therefore, activation of MOC neurons by a 5-HT3 receptor agonist can improve the insufficient speech discrimination ability in a noisy environment.
  • composition of the present invention can be suitably used for the prevention or treatment of insufficient speech discrimination ability in a noisy environment, and can be suitably used for preventing or treating insufficient speech discrimination ability in a noisy environment even if hearing is normal. It can be further suitably used for treatment.
  • 5-HT3 receptors play a fundamental role in the MOC feedback system and are involved in hearing loss due to exposure to high-intensity sounds. Stimulation of 5-HT3 receptors attenuates hearing loss and loss of ribbon synapses due to high-intensity sound exposure and enhances cochlear protection by the MOC feedback system. Therefore, pharmacological enhancement of MOC neuron activity via 5-HT3 receptors allows for the prevention and treatment of hearing loss caused by exposure to high-intensity sounds. Patients with functional hearing loss (e.g., loud sound exposure hearing loss and age-related hearing loss) with normal hearing often have poor speech discrimination in noisy environments, including tinnitus and hyperacusis. The patient exhibits auditory symptoms such as paresthesia.
  • functional hearing loss e.g., loud sound exposure hearing loss and age-related hearing loss
  • the patient exhibits auditory symptoms such as paresthesia.
  • 5-HT3 receptors may be an important therapeutic target for the treatment of auditory symptoms associated with dysfunction of the MOC feedback system, allowing for prevention and treatment with 5-HT3 receptor agonists.
  • the prophylactic or therapeutic composition in the present invention includes a prophylactic composition, a therapeutic composition, and a prophylactic and therapeutic composition.
  • Prevention or treatment in the present invention includes prevention of onset, improvement of symptoms, suppression of exacerbation of symptoms, prevention of recurrence of symptoms, early recovery of symptoms, etc. with respect to one or more symptoms related to hearing impairment.
  • the composition of the invention may preferably be a therapeutic composition.
  • a therapeutic composition is a composition that is administered for the purpose of preventing the onset of symptoms, improving symptoms, suppressing exacerbation of symptoms, preventing recurrence of symptoms, early recovery of symptoms, and the like.
  • composition of the present invention may contain two or more types of serotonin 3 receptor agonists as active ingredients.
  • the composition of the present invention may contain a hearing impairment therapeutic other than a serotonin 3 receptor agonist.
  • the composition of the present invention may contain drugs other than the hearing impairment therapeutic.
  • composition of the present invention can include a serotonin 3 receptor agonist as an active ingredient and a pharmaceutically acceptable carrier.
  • Such carriers include excipients (for example, sugar derivatives such as mannitol and sorbitol; starch derivatives such as corn starch and potato starch; or cellulose derivatives such as crystalline cellulose), lubricants (for example, stearic acid metal stearates such as magnesium; or talc, etc.), binders (e.g., hydroxypropylcellulose, hydroxypropylmethylcellulose, or polyvinylpyrrolidone, etc.), disintegrants (e.g., cellulose derivatives such as carboxymethylcellulose, carboxymethylcellulose calcium, etc.), Water, preservatives (e.g.
  • paraoxybenzoic acid esters such as methylparaben, propylparaben; or alcohols such as chlorobutanol, benzyl alcohol, etc.
  • pH adjusters e.g. inorganic acids such as hydrochloric acid, sulfuric acid or phosphoric acid, acetic acid
  • organic acids such as succinic acid, fumaric acid, or malic acid, or their salts
  • commonly used carriers for pharmaceutical preparations such as diluents (e.g., water for injection, etc.), singly or in combination of two or more. It can be blended.
  • the composition of the present invention includes a solution in which the active ingredient is dissolved in water.
  • the serotonin 3 receptor agonist which is the active ingredient of the present invention, is mixed with the above-mentioned carrier as necessary, and then prepared into tablets, granules, capsules, powders, solutions, suspensions, emulsions, etc. It can be administered orally in the form of a suppository, injection, intravenous infusion, transdermal, transmucosal, or inhaled parenterally.
  • the serotonin 3 receptor agonist which is the active ingredient of the present invention, is formulated into the above-mentioned dosage form and then administered to a subject in need thereof, such as a human or an animal, preferably a human.
  • composition of the present invention can be administered to a subject in need thereof as a medicine, food, or drink.
  • a medicine e.g., a medicine, food, or drink.
  • it can be administered as a medicine.
  • the dosage and frequency of administration of the serotonin 3 receptor agonist of the present invention can be changed as appropriate depending on conditions such as the severity of symptoms, age, weight, sex of the patient, type of drug, dosage form, and route of administration.
  • the active ingredient is administered parenterally, such as subcutaneously, intravenously, intraperitoneally, intramuscularly, or intrarectally, at a dose of about 0.01 to 10 mg/kg body weight, preferably about 0.01 to 10 mg/kg body weight per administration. about 0.1 to 5 mg/kg body weight, particularly preferably about 0.3 to 3 mg/kg body weight, and orally about 0.01 to 100 mg/kg body weight, preferably about 0.1 to 50 mg/kg body weight. , particularly preferably about 1 to 30 mg/kg body weight.
  • the frequency of administration may also be one or more times per day, such as 1 to 3 times, 1 to 2 times, or once per day.
  • the serotonin 3 receptor agonist of the present invention can be produced according to known methods.
  • the compound represented by formula (I) or a pharmaceutically acceptable salt thereof can be produced by the method described in Patent Document 1.
  • compound H, I, J, K, L, M, N, O or P can be manufactured by the method described in International Publication No. WO2016/027757.
  • Commercially available compounds can also be used as compounds A, B, C, D, E, F, or G.
  • the present invention also relates to a method for screening a compound for prevention or treatment of sensorineural hearing loss, which comprises a step of measuring serotonin 3 receptor agonist activity.
  • the compound for preventing or treating sensorineural hearing loss is preferably a compound for preventing or treating acoustic trauma or age-related hearing loss. More preferably, it is a compound for preventing or treating hearing loss due to exposure to loud noises.
  • the present invention relates to a method of screening for a MOC neuron activating compound or a compound for preventing or treating a hearing disorder involving MOC neurons, which comprises the step of measuring serotonin 3 receptor agonist activity.
  • the screening method of the present invention includes, for example, the step of measuring serotonin 3 receptor agonist activity for a compound library.
  • the compound library may be known or unknown.
  • Known compound libraries include compound libraries that have already been approved by food (e.g., U.S. Food and Drug Administration (FDA)) or drugs (e.g., European Medicines Agency (EMEA)) (e.g., PRESTWICK).
  • Chemical libraries this is a collection of compounds whose patent terms have expired), and compound libraries that are a collection of compounds that have not yet been approved for food or medicine.
  • cells Xenopus oocytes, HEK293 cells, etc. are made to express cDNA of serotonin 3 receptor subunit A, or A and B.
  • a method of electrophysiologically measuring the current flowing into cells (Nakamura Y et al. Biochem Biophys Res Commun. 415(2) (2011) 416-20) and fluorescent membrane-poten Fluorescence intensity using tial sensitive dye Examples include a method of measuring the current flowing into the cell by measuring the current flowing into the cell (Lummis et al. Neuropharmacology 73 (2013) 241-246). In either method, serotonin 3 receptor agonist activity can be measured by administering the compound to cells and examining the response obtained.
  • the screening method of the present invention may further include the step of selecting compounds based on the measured serotonin 3 receptor agonist activity.
  • the compounds obtained by the screening method of the present invention have serotonin 3 receptor agonist activity and can activate MOC neurons, and also prevent or treat hearing disorders involving MOC neurons and sensorineural hearing loss. It can be used for prevention or treatment.
  • SR57227A (TOCRIS, hydrochloride of compound A) was dissolved in physiological saline to prepare an injection preparation (0.5 mg/ml).
  • Htr3a ⁇ / ⁇ mice were backcrossed with C57BL/6J mice for at least 10 generations as previously reported (Kondo et al. Mol Psychiatry. 2018;23:833-842). Since 5-HT3A is essential for the formation of a functional receptor, Htr3a ⁇ / ⁇ mice are mice deficient in 5-HT3 receptor function.
  • Htr3a ⁇ / ⁇ mice are mice deficient in 5-HT3 receptor function.
  • Our previous study showed that EGFP expression reflects normal 5-HT3 receptor expression in 5-HT3AR-EGFP transgenic reporter mice (Koyama et al. Sci Rep. 2017;7:42884). All mice were kept at 23-25°C under a controlled light-dark cycle and had standard laboratory chow and water ad libitum. All mice were randomly
  • ABR Auditory brainstem response
  • Thresholds were determined by decreasing the stimulus intensity in 5 dB steps (from 80 dB SPL to less than 5 dB) until the waveform lost its reproducible morphology. At each sound level, 1024 responses were averaged.
  • DPOAEs Distortion Product Otoacoustic Emissions
  • CS contralateral suppression
  • a wideband high-intensity sound (3-30 kHz bandwidth) was delivered to the contralateral ear at 55 dB.
  • the magnitude of the CS was calculated and defined by subtracting the distortion component (DP) (dBSPL) under quiet conditions from the distortion component (DP) (dBSPL) associated with the contralateral sound at each test frequency.
  • mice were treated with saline or 5 mg/kg of SR57227A [4-amino-1-(6-chloro-2-pyridyl)-piperidine hydrochloride, Sigma, USA; Cat # S1688] (selective 5-HT3 receptor agonist) was administered intraperitoneally 30 minutes before exposure to loud noise. Then, 7 days after the exposure to intense sound, DPOAE and ABR tests were conducted as described above.
  • the isolated cochlea was fixed with 4% paraformaldehyde in 0.1 M phosphate buffer (PBS) for 2 h and decalcified with 10% EDTA for 4 days (Hanada et al. Sci Rep. 2018;8: 11491).
  • PBS phosphate buffer
  • the basement membrane containing the organ of Corti was microdissected and divided into three regions: basal, middle, and apical (Boero et al. J Neurosci.2018;38:7440-7451 ).
  • Microdissected sections were treated with antibodies against GFP (chicken; Abcam, UK; 1:1000; Cat# ab13970, RRID: AB_300798) and choline acetyltransferase (ChAT) (goat; Merck Millipore, USA; 1:200; Immunostained with Cat# AB144P, RRID: AB_2079751). Sections were also stained with the nuclear dye 4',6-diamidino-2-phenylindole (DAPI; Thermo Fisher Scientific, USA; Cat# D1306, RRID: AB_2629482). Images of the specimens were acquired with an LSM880 confocal laser scanning microscope (Carl Zeiss, Jena, Germany).
  • DAPI nuclear dye 4',6-diamidino-2-phenylindole
  • Images were collected in a 1024 ⁇ 1024 raster using a high resolution oil immersion objective (63 ⁇ , numerical aperture 1.3). Images were loaded into image processing software (ZEN, Carl Zeiss). The green, red, and blue channels were analyzed separately to generate the maximum projection. The maximum projections from each channel were merged and converted into triplicate images.
  • mice were anesthetized and perfused transcardially with 4% paraformaldehyde in 0.1 M PBS. The temporal bone was then removed, postfixed, and decalcified (Whitlon et ai. Brain Res Brain Res Protoc. 2001;6:159-166). Cochlear samples were cut into 10 ⁇ m thick sections using a cryostat and immunostained with antibodies against GFP and ChAT. The sections were counterstained with DAPI.
  • mice were anesthetized by intraperitoneal injection of a mixture of ketamine (100 mg/kg) and xylazine (10 mg/kg). Under the microscope, the tympanic membrane was visualized by making a small incision in the ear canal cartilage. Using a 5 ⁇ L Hamilton syringe with a 32G blunt needle, add 3 ⁇ L of 5% Fluorogold (FG) (Sigma-Aldrich, USA; Ca# 223769-64-0) dissolved in 0.9% saline. ) was slowly injected through the inferior posterior quadrant of the tympanic membrane (Dean et al. Otol Neurotol. 2012;33:1085-1091).
  • FG Fluorogold
  • mice were sacrificed 5 days after FG injection, and whole brains were removed for immunofluorescence staining.
  • intratympanic injection of FG was performed because intratympanic injection of a neuron tracer was reported to be more specific and less invasive than intracochlear injection for tracking cochlear efferent neurons.
  • Ta For quantitative analysis of EGFP (Fig. 1D) and c-Fos (Fig. 3B) expression in FG-labeled MOC neurons, 50 FG-labeled MOC neurons from three mice were evaluated.
  • mice were anesthetized and perfused transcardially with 4% paraformaldehyde in 0.1 M PBS (pH 7.4). The whole brain of each mouse was removed and fixed in 4% paraformaldehyde overnight at 4°C, then placed in 30% sucrose in 0.1 M PBS at 4°C (Kondo et al. Neuron. 2012;73: 743-757). The brains were then embedded in OCT compound and frozen. Brain samples were cut into 20 ⁇ m coronal sections by cryostat.
  • the location of MOC neurons was determined according to the mouse brain map (Franklin & Paxinos 2007).
  • To quantify c-Fos-positive cells in the MOC feedback system every fourth coronal section from the brain of each mouse was evaluated (total of 10 sections per mouse) ( Figure 3E) (Ueda et al. Biochem Biophys Res Comm . 2018;506:498-503).
  • Figure 3E To quantitatively analyze c-Fos expression in EGFP-positive MOC neurons after high-intensity sound exposure, 50 EGFP-positive cells from three 5-HT3AR-EGFP transgenic reporter mice were evaluated (Fig. 3C). .
  • anti-GFP dry; Abcam; 1:1000; Cat# ab13970, RRID: AB_300798
  • anti-c-Fos rabbit; Santa Cruz Biotechnology, USA; 1:1000; Cat# sc-52 , RRID: AB_2106783
  • Z-stack images are obtained from each part of the cochlear surface preparation (basal, middle, and apical) from the inner spiral nerve bundle downward to the synaptic poles of approximately 16 inner hair cells. , with a z step of 0.25 ⁇ m. Images were collected in a 1024 ⁇ 1024 raster using a high-resolution oil immersion objective (63 ⁇ , numerical aperture 1.3), and digital zoom ( ⁇ 2). Images were loaded into ZEN image processing software and inner hair cells (IHCs) were identified by CtBP2-stained nuclei. The green and red channels were analyzed separately and the maximum projection was generated to quantify CtBP2 and GluA2 positive puncta. Maximum projections from each channel were merged and converted to a binary image.
  • IHCs inner hair cells
  • mice were treated with saline, 5 mg/kg SR57227A (selective 5-HT3 receptor agonist), or 3 mg/kg ondansetron (Tokyo Kasei Kogyo, Tokyo). Japan; Cat# O0470) (selective 5-HT3 receptor antagonist) was injected intraperitoneally 30 minutes before loud sound exposure. These doses were selected according to previous reports (Kondo M. et al. Mol Psychiatry. 2018;23:833-842). Next, 24 hours after exposure to intense sound, microdissection of the central cochlea was performed as described above.
  • Both OHC and IHC are innervated by afferent and efferent nerve fibers.
  • Afferent fibers are the dendrites of the cochlear nerve, and their neuronal cell bodies are located in the spiral ganglion.
  • efferent fibers originate in the superior olivary nucleus (SOC) of the brainstem, where MOC and LOC neurons are located.
  • SOC superior olivary nucleus
  • MOC neurons innervate the OHC
  • LOC neurons innervate afferent fibers that contact the IHC.
  • 5-HT3 receptors are expressed in SOC neurons (Koyama et al. Sci Rep. 2017;7:42884).
  • 5-HT3AR-EGFP transgenic reporter mice we investigated the expression pattern of 5-HT3 receptors in SOC neurons in more detail. Immunohistochemical analysis of reporter mice showed EGFP signals only in MOC neurons (Fig. 1A,B). To confirm efferent innervation by MOC neurons, we performed retrograde neuronal tracing of the cochlear auditory pathway by intratympanic administration of FG to 5-HT3AR-EGFP reporter mice. FG labeling was detected in both MOC and LOC neurons ipsilateral to the injection, whereas contralaterally, FG labeling was observed only in MOC neurons (Fig. 1C). This is consistent with previous reports on the branching pattern of olivocochlear neurons.
  • the efferent fibers of MOC neurons pass through the spiral ganglion, pass through the tunnel of Corti, and form synaptic connections with OHCs.
  • 5-HT3AR-EGFP reporter mice show EGFP signals throughout neurons, including axons and dendrites expressing 5-HT3 receptors, we further hypothesized that OHC in the cochlea by 5-HT3 receptor-expressing MOC neurons.
  • EGFP-positive fibers were confirmed by immunostaining of cochlear sections (Fig. 2B). Since cochlear efferent fibers are cholinergic, ChAT is used as a marker for efferent fibers. Our analysis showed that ChAT signals were located in fibers extending downwards in the OHC across the tunnel of Corti (Fig. 2A,B). Furthermore, double immunostaining revealed that in the cochlea, EGFP-positive fibers and large terminals of OHCs colocalized with ChAT signals (Fig. 2A,B), indicating that EGFP-positive fibers project to OHCs It was suggested that these were sexual fibers. The EGFP signal observed in IHC (Fig.
  • 2A,B may be a bundle of MOC fibers in the inner spiral bundle rather than LOC fibers innervating afferent fibers contacting IHC.
  • FIGS 1 to 3 show that 5-HT3 receptors are expressed in MOC neurons activated by high-intensity sounds.
  • MOC neurons are neurons that innervate the OHC.
  • DPOAE is a sound generated by the distortion of output sound for two types of input sound through the sensory epithelium, which is converted into mechanical movement, amplified by OHC through MOC, and then back-propagated to the eardrum. Can be measured with a microphone. Therefore, DPOAE is used to assess OHC function and the regulatory effects of MOC neurons on these cells. It has been reported that MOC function can be analyzed by DPOAE measurement with contralateral high-intensity stimulation that induces MOC activity (Zhu X. et al.
  • the present invention contributes to the prevention and treatment of hearing impairment.

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Abstract

Le problème à résoudre par la présente invention est de clarifier le mécanisme du système de rétroaction olivocochléaire médial (MOC) et de fournir une composition permettant de prévenir ou de traiter des troubles auditifs dans lesquels des neurones MOC participent, ainsi que de fournir une méthode de dépistage d'un composé permettant de prévenir ou de traiter des troubles auditifs dans lesquels des neurones MOC participent. La solution de l'invention concerne une composition permettant de prévenir ou de traiter une perte d'audition neurosensorielle, la composition contenant un agoniste du récepteur de la sérotonine 3. La perte d'audition neurosensorielle comprend une perte d'audition par traumatisme acoustique, une perte d'audition liée à l'âge, etc. L'invention concerne également une composition permettant d'activer des neurones MOC, la composition contenant un agoniste du récepteur de la sérotonine 3. L'agoniste du récepteur de la sérotonine 3 active les neurones MOC et permet ainsi la prévention et le traitement de la perte d'audition neurosensorielle. L'invention concerne également : une méthode de dépistage d'un composé permettant de prévenir ou de traiter une perte d'audition neurosensorielle, ladite méthode comprenant une étape consistant à mesurer l'activité de l'agoniste du récepteur de la sérotonine 3 ; et une méthode de dépistage d'un composé activant des neurones MOC.
PCT/JP2023/012857 2022-03-30 2023-03-29 Composition de prévention ou de traitement de perte d'audition neurosensorielle WO2023190707A1 (fr)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015107995A (ja) * 2009-05-20 2015-06-11 インセルム（インスティチュート ナショナル デ ラ サンテ エ デ ラリシェルシェ メディカル） 損傷性前庭障害の処置における使用のためのセロトニン５−ｈｔ３受容体拮抗薬
US10434097B1 (en) * 2015-09-14 2019-10-08 Gateway Biotechnology, Inc. Methods and compositions for treating hearing disorders

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015107995A (ja) * 2009-05-20 2015-06-11 インセルム（インスティチュート ナショナル デ ラ サンテ エ デ ラリシェルシェ メディカル） 損傷性前庭障害の処置における使用のためのセロトニン５−ｈｔ３受容体拮抗薬
US10434097B1 (en) * 2015-09-14 2019-10-08 Gateway Biotechnology, Inc. Methods and compositions for treating hearing disorders

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
CRUZ OSWALDO LAERICO M., KASSE CRISTIANE A, SANCHEZ MAURA, BARBOSA FLAVIO, BARROS FLAVIA A: "Serotonin Reuptake Inhibitors in Auditory Processing Disorders in Elderly Patients: Preliminary Results", THE LARYNGOSCOPE, vol. 114, 1 September 2004 (2004-09-01), pages 1656 - 1659, XP093096398 *
KANG HSIAO-HSIEN; WANG CHIH-HUNG; CHEN HSIN-CHIEN; LI I-HSUN; CHENG CHENG-YI; LIU REN-SHYAN; HUANG WEN-SHENG; SHIUE CHYNG-YANN; MA: "Investigating the effects of noise-induced hearing loss on serotonin transporters in rat brain using 4-[18F]-ADAM/small animal PET", NEUROIMAGE, ELSEVIER, AMSTERDAM, NL, vol. 75, 2 July 2012 (2012-07-02), AMSTERDAM, NL , pages 262 - 269, XP028579875, ISSN: 1053-8119, DOI: 10.1016/j.neuroimage.2012.06.049 *
KOYAMA YOSHIHISA, KONDO MAKOTO, SHIMADA SHOICHI: "Building a 5-HT3A Receptor Expression Map in the Mouse Brain", SCIENTIFIC REPORTS, vol. 7, no. 1, XP093096401, DOI: 10.1038/srep42884 *
OHATA KAZUYA, KONDO MAKOTO, OZONO YOSHIYUKI, HANADA YUKIKO, SATO TAKASHI, INOHARA HIDENORI, SHIMADA SHOICHI: "Cochlear protection against noise exposure requires serotonin type 3A receptor via the medial olivocochlear system", THE FASEB JOURNAL, FEDERATION OF AMERICAN SOCIETIES FOR EXPERIMENTAL BIOLOGY, US, vol. 35, no. 5, 1 May 2021 (2021-05-01), US, XP093096347, ISSN: 0892-6638, DOI: 10.1096/fj.202002383R *
OHATA KAZUYA: "Cochlear protection against noise exposure requires serotonin type 3A receptor via the medial olivocochlear system", OSAKA UNIVERSITY KNOWLEDGE ARCHIVE, 17 December 2021 (2021-12-17), XP093096355, Retrieved from the Internet <URL:https://ir.library.osaka-u.ac.jp/repo/ouka/all/85239/32114_Abstract.pdf> *
OHATA, KAZUYA ET AL.: "O38-1 Cochlear protection against noise exposure requires serotonin type 3A receptor via the medial olivocochlear system", THE 31ST ANNUAL MEETING OF THE JAPAN OTOLOGICAL SOCIETY; TOKYO, JAPAN; OCTOBER 13-16, 2021, vol. 31, 13 October 2021 (2021-10-13), pages 356, XP009549840 *

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