HAIR-GROWING AGENT

Abstract: A hair-growing agent which exhibits a strong hair-­ growing effect. The hair-growing agent according to the present invention contains as an effective ingredient an aliphatic carboxylic acid having an odd number of carbon atoms or a derivative thereof.

Description: The present invention relates to an agent for use in a method for the treatment of alopecia comprising a specific aliphatic acid or an ester thereof. Furthermore, the present invention relates to the use of one of the specific compounds in hair-growing agents. Hair-growing agents containing various agents exhibiting pharmaceutical properties are known. Such pharmaceutical agents may include, for example, a vitamin such as vitamin E, an amino acid such as serine or methionine, a vasodilator such as an acetylcholine derivative, an anti-inflammatory agent such as lithospermum root extract, a female sex hormone such as estradiol, a skin function stimulant such as cepharanthine, a melanine synthesis catalyst such as copper pantothenate or a keratolytic such as salicylic acid. These agents may assist in the prevention and cure of alopecia. There are known cases where an aliphatic carboxylic acid or a derivative thereof such as natural vegetable oil, e.g., olive oil and castor oil, or stearic acid is contained in a hair cosmetic such as a hair tonic to improve performance of the product. Aliphatic carboxylic acids constituting various naturally occurring lipids, such as vegetable oils and animal oils, are in almost all cases aliphatic carboxylic acids having an even number of carbon atoms, whether they are saturated aliphatic carboxylic acids such as stearic acid and palmitic acid or unsaturated aliphatic carboxylic acids such as oleic acid and linoleic acid. In DE-A 2913040 there are described cosmetic agents containing glycerides of propionic acid and urea. In FR-A 2236484 is described a hair-treating agent which contains an ester or an amide of nonanoic acid. Conventional hair-growing agents are claimed to be effective in preventing or improving dandruff, itchiness and hair loss as well as an accelerating hair generation and growth. However, it seems that a satisfactory effect has not yet been obtained. Therefore, the object of the present invention is to provide an agent for use in a method for the treatment of alopecia comprising an aliphatic carboxylic acid selected from undecanoic acid, tridecanoic acid, pentadecanoic acid and heptadecanoic acid, or an ester thereof, as an effective ingredient. The agent according to the present invention provides a strong hair-growing effect. Alopecia may arise from various causes. In each case, individual hairs cannot complete their normal hair cycle to reach the telogen state. In order to decrease baldness and accelerate hair generation, it is necessary to bring the hair follicles from the telogen state into the normal anagen state. As a result of extensive research into the conversion of hair from the telogen state into the anagen state, it has been found that an aliphatic carboxylic acid having an odd number of carbon atoms and a derivative thereof exhibit a remarkable hair-growing effect. The present invention is based on this finding. The aliphatic carboxylic acid to be used for the agent according to the present invention is an aliphatic carboxylic acid selected from undecanoic acid, tridecanoic acid, pentadecanoic acid and heptadecanoic acid, or an ester thereof. Preferred esters include the following: A) a monoglyceride represented by the general formula (I) or (II): where R₁ is an aliphatic group remaining of one of the carboxylic acids as mentioned above. B) a diglyceride represented by the general formula (III) or (IV): where at least one of R₂ and R₃ is an aliphatic group remaining of one of the carboxylic acids as mentioned above. It should be noted here that the effect to be accomplished by the present invention can be achieved if either R₂ or R₃ represents an aliphatic group as mentioned above while the other represents a hydrogen or an aliphatic group having an odd number of carbon atoms or another organic group which does not adversely affect the human body. However, a diglyceride of one of the specific aliphatic carboxylic acids is particularly preferred. C) a triglyceride represented by the general formula (V): where at least one of R₄, R₅ and R₆ is an aliphatic group remaining of one of the carboxylic acids as mentioned above. It should be noted here that, where at least one of R₄, R₅ and R₆ is an aliphatic group as mentioned above, the effect sought by the present invention can be achieved even if the others are in each case hydrogen or an aliphatic group having an odd number of carbon atoms or another organic group which does not adversely affect the human body. However, a triglyceride of one of the specific carboxylic acids is particularly preferred. D) an ester represented by the general formula (VII): where R₈ is an aliphatic group remaining of one of the carboxylic acids as mentioned above, R₉ is a residue of a primary or secondary alcohol, an amine residue, a polyoxyethylene residue, a sorbitan residue or a sucrose residue. A representative primary alcohol may be methanol and ethanol, and a representative amine residue is mono-, di- and tri-ethanolamine. E) a sterol ester represented by the general formula (XII): where R₂₀ is an aliphatic group remaining of one of the carboxylic acids as mentioned above. F) a phospholipid represented by the general formula (XIII): where at least one of R₂₁ and R₂₂ is an aliphatic group remaining of one of the carboxylic acids as mentioned above and the other may be a hydrogen or an organic group having no adverse effect on the human body. However, it is preferred that both of R₂₁ and R₂₂ are independently an aliphatic group of the specific type. X is a choline residue, an ethanolamine residue, a serine residue or an inositol residue. When X is a choline residue, it represents a phosphatidyl choline. When X is an ethanolamine residue, it represents a phosphatidyl ethanolamine. When X is a serine residue, it represents a phosphatidyl serine. When X is an inositol residue, it respresents a phosphatidyl inositol. G) a phosphatidic acid represented by the general formula (XIV): where at least one of R₂₃ and R₂₄ is an aliphatic group remaining of one of the carboxylic acids as mentioned above and the other is a hydrogen or an organic group having no adverse effect on the human body. However, it is preferred that both of R₂₃ and R₂₄ are independently an aliphatic group of the specific type. The agent according to the present invention may be used in a conventional manner in a variety of forms such as an agent for an endermic liniment, for internal use, an agent to be taken by injection, a hair-tonic hair lotion or hair cream. In addition to the above-mentioned effective ingredients, the agent according to the present invention may usually contain a cosmetically or pharmaceutically acceptable carrier. Such a carrier is not described in detail here, since is is well known in this field. Examples of such a carrier include water; ethanol; a polyol such as ethylene glycol, propylene glycol, 1,3-butylene glycol, glycerine or sorbitol; a siloxane such as dimethyl polysiloxane, phenyl polysiloxane or polyoxyalkylene polysiloxane; an animal or vegetable oil such as sperm oil or jojoba oil; liquid paraffin; vaseline; paraffin wax; squalane; and an olefin oligomer. The agent according to the present invention may also contain an effective ingredient that is conventionally used. Such an effective ingredient may include, for example, a vitamin such as vitamin E, a hormone such as estradiol, a vasodilator such as an acethylcholine derivative, an amino acid such as serine or methionine, an anti-inflammatory agent such as lithospermum root extract, a skin function stimulant such as cepharanthine, or a keratolytic such as salicylic acid. Test 1: Animal Study for Evaluating Effectiveness Aliphatic carboxylic acids and derivatives thereof were tested for their hair-growing effects. The tested substances were linear saturated aliphatic carboxylic acids having carbon atoms in variously odd and even numbers, and triglycerides of the aliphatic carboxylic acids. Test specimens were prepared by dissolving each test substance to be tested in ethanol. Concentrations of the test substance were 0.3, 3.0 and 10.0% by weight, respectively. As a control, ethanol containing no test substance was also tested. The test animals were groups of 6 to 8 male rabbits of New Zealand White species each weighing about 2.5 kg from whose backs hair was removed. Rabbits in the telogen state alone were used. The test specimen was applied in the amount of 0.2 ml twice per week for 30 to 60 days to the area of the rabbits' backs from which the hair had been removed. The test was conducted by observing the number of days required for the conversion of hair from the telogen state into the anagen state. The results are shown in Table 1 below. In the Table, "shortened days" means the number of days by which the conversion of the telogen state into anagen state is shortened, compared with the control in which ethanol containing no test substance was applied. For example, when the number of shortened days is 10, it means that the conversion of telogen state into anagen state occurred 10 days earlier than the control experiment. It can be seen from Table 1 that the specific aliphatic carboxylic acids having an odd number of carbon atoms and the glycerides thereof have significant hair-growing effects whereas the aliphatic carboxylic acids having even-numbered carbon chains as long as the former and the glycerides thereof have no hair-growing effect. Test 2: Human Study for Evaluating Effectiveness A composition comprising 10.0% by weight of n-triundecanoin, 1.0% by weight of castor oil, 0.5% by weight of pyrrolidone carboxylic acid, 0.5% by weight of a perfume and 88% by weight of 80% ethanol was prepared. This composition was then used by patients (totaling 25 patients) suffering from various types of alopecia over a period of 3 to 6 months. The effects were evaluated according to subjective observation by the patients themselves. The results are shown in Table 2 below. It can be seen from Table 2 that the agent according to the present invention is effective for various types of alopecia, particularly for male alopecia such as alopecia praematura and alopecia praesenilis as well as alopecia areata. Test 3: Human Study for Evaluating Safety Pieces of gauze of 1 cm in diameter were soaked with the composition prepared for Test 2. As a control, pieces of gauze of 1 cm in diameter were soaked with water. Two pieces of each type of gauze (totaling 4 pieces) were attached as a closed patch by means of a fin chamber to the antebrachial flexor side of 25 healthy females for 24 hours. The skin conditions were observed after 30 minutes and 24 hours of the removal of the gauze. The result was that none of the woman had any skin irritation. The following indicates forms and compositions as examples of the agents according to the present invention. In the following, the compositions are expressed in terms of % by weight. Example 1 Composition for Endermic Liniment Ingredient Amount 80% ethanol 88 n-triundecanoin 10.0 Castor oil 1.0 Pyrrolidone carboxylic acid 0.5 Perfume 0.5 Example 2 Composition for Endermic Liniment Ingredient Amount 90% ethanol 92.5 n-tritridecanoin 5.0 Olive oil 1.0 Glycyrrhizin 1.0 Perfume 0.5 Example 3 Composition for Endermic Liniment Ingredient Amount 90% ethanol 89.5 Ethyl n-tridecanoate 3.0 Liquid paraffin 5.0 Polyethylene glycol 2.0 Perfume 0.5 Example 4 Cream Composition Ingredient Amount n-tripentadecanoin 10.0 Olive oil 5.0 Liquid paraffin 51.0 Beeswax 1.0 Sorbitan sesquioleate 3.0 Purified water 30.0 Example 5 Composition for Internal Use Ingredient Amount n-tripentadecanoin 68.0 Lactose 20.0 Corn starch 10.0 Magnesium stearate 2.0 Example 6 Composition to be taken by Injection Ingredient Amount Tritridecanoin 0.5 Olive oil 99.5

Claims: An agent for use in a method for the treatment of alopecia comprising an aliphatic carboxylic acid selected from undecanoic acid, tridecanoic acid, pentadecanoic acid and heptadecanoic acid, or an ester thereof, as an effective ingredient. The agent according to claim 1, wherein said ester is a monoglyceride represented by the general formula: where R₁ is an aliphatic group remaining of one of the carboxylic acids as mentioned in claim 1. The agent according to claim 1, wherein said ester is a diglyceride represented by the general formula: where R₂ and R₃ are independently a hydrogen atom or an organic group, at least one thereof being an aliphatic group remaining of one of the carboxylic acids as mentioned in claim 1. The agent according to claim 1, wherein said ester is a triglyceride represented by the general formula: where R₄, R₅ and R₆ are independently a hydrogen atom or an organic group, at least one thereof being an aliphatic group remaining of one of the carboxylic acids as mentioned in claim 1. The agent according to claim 1, wherein said ester is an ester represented by the general formula: where R₈ is an aliphatic group remaining of one of the carboxylic acids as mentioned in claim 1, R₉ is a residue of a primary or secondary alcohol, a polyoxyethylene residue, a sorbitan residue or a sucrose residue. The agent according to claim 1, wherein said ester is a sterol represented by the general formula: where R₂₀ is an aliphatic group remaining of one of the carboxylic acids mentioned in claim 1. The agent according to claim 1, wherein said ester is a phospholipid represented by the general formula: where R₂₁ and R₂₂ are independently a hydrogen atom or an organic group, at least one thereof being an aliphatic group remaining of one of the carboxylic acids as mentioned in claim 1, and X is a choline residue, an ethanolamine residue, a serine residue or an inositol residue. The agent according to claim 1, wherein said ester is a phosphatidic acid represented by the general formula: where at least one of R₂₃ and R₂₄ is an aliphatic group remaining of one of the carboxylic acids mentioned in claim 1, and the other is hydrogen or an organic group having no adverse effect on the human body. The use of one of the compounds defined in claims 1 to 8 in hair-growing agents.

Inventors: ADACHI, KUNIAKI, SADAI, MASANAO, TAMAI, HIDEO
Applicants: LION CORPORATION
Application year: 1983
Main classification: A61K7
IPC codes: A61K8, A61K31, A61Q5, A61Q7