Cosmetic use of a composition for the care of keratinous materials comprising at least indole-3-pyruvic acid

Abstract

Cosmetic Use of a Composition for the Care of Keratinous Materials Comprising at Least of Indole-3-Pyruvic Acid. The present invention relates to the cosmetic, particularly topical, non-therapeutic use of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers, or one of its salts, to prevent a decrease in the skin barrier function and / or to strengthen the skin barrier function in an individual, particularly in dry skin. It also relates to the use of such a composition to prevent and / or treat a skin disorder in sensitive skin in an individual, as well as the use of such a composition to prevent and / or treat pruritus and / or inflammation of the skin in an individual.A non-therapeutic cosmetic process for the care of keratinous materials, particularly of the skin, comprising the topical application of such a composition to these keratinous materials. Figure for the abstract: None.

Description

Title of the invention: Cosmetic use of a composition for the care of keratinous materials comprising at least indole-3-pyruvic acid technical field

[0001] The present invention relates to the use of indole-3-pyruvic acid to improve the skin barrier function and moisturize the skin.

[0002] More particularly, the present invention aims to propose the cosmetic use, in particular topical, non-therapeutic use of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent a decrease in the skin barrier function and / or strengthen the skin barrier function in an individual, in particular of dry skin.

[0003] It also relates to the cosmetic use, in particular topical, of such a composition to prevent and / or treat atopic dermatitis or eczema.

[0004] It also relates to the cosmetic use, in particular topical, non-therapeutic use of such a composition to prevent and / or treat a skin disorder of sensitive skin, in an individual.

[0005] It also relates to the cosmetic use, particularly topical, of such a composition to prevent and / or treat itching and / or inflammation of the skin in a particular individual present in a dermatological disorder chosen from the group consisting of atopic dermatitis or eczema, psoriasis, prurigo nodularis, seborrheic dermatitis, acne, folliculitis, rosacea. Prior art

[0006] The skin is a tissue whose cells are tightly joined and interconnected. The cutaneous tissue forms an external covering comprising sebaceous or sweat glands and hair follicles. The skin, and particularly the scalp, consists of epithelia that undergo continuous renewal. This renewal, or desquamation, is a coordinated and finely regulated process resulting in the insensible and imperceptible shedding of superficial cells.

[0007] Human skin consists of two compartments, namely a superficial compartment, the epidermis, and a deep compartment, the dermis.

[0008] The epidermis is conventionally divided into a basal layer of keratinocytes constituting the germinal layer of the epidermis, a so-called spinous layer consisting of several layers of polyhedral cells arranged on the germinal layers, one to three so-called granular layers consisting of flattened cells containing distinct cytoplasmic inclusions, the keratohyalin granules, and finally, a set of upper layers called stratum corneum (or stratum comeum), made up of keratinocytes at the terminal stage of their differentiation called comeocytes.

[0009] Keratinocytes are anucleate cells mainly composed of fibrous material containing cytokeratins, surrounded by a corneal envelope. New keratinocytes are constantly produced to compensate for the continuous loss of epidermal cells in the stratum corneum through a mechanism called desquamation.

[0010] However, an imbalance between cell production in the basal layer and the desquamation rate can lead to the formation of scales on the skin surface. Similarly, a deficiency in terminal differentiation of stratum comeum cells, for various reasons, can lead to the formation of large, thick, visible cell clumps known as "scales," or, in other situations, to a thinning of the stratum comeum.

[0011] This can lead to a weakening of the barrier properties of the epidermis, to chronic dehydration of the stratum corneum, a loss of mechanical elasticity, tightness, as well as a lack of radiance and transparency of the skin.

[0012] As an example of factors that promote a decrease in the surface quality of the skin, which weakens the skin barrier, we can mention stress, the winter period, excess sebum or a lack of hydration.

[0013] Thus, a fragility of the skin barrier can occur in the presence of external aggressions, in particular chosen from among irritants (detergents, acids, bases, oxidants, reducers, concentrated solvents, harmful gases or fumes, pollutants), thermal or climatic imbalances (cold, dryness, radiation), xenobiotics (undesirable microorganisms, allergens) or internal aggressions such as psychological stress.

[0014] This alteration of the skin barrier can result in skin discomfort, sensory phenomena, and in particular unpleasant sensations. The affected individual may then experience a feeling of skin discomfort which may manifest itself in particular as tingling, tightness, burning and / or itching.

[0015] These sensations of skin discomfort, of a cosmetic and non-therapeutic nature, are more frequent in the most exposed areas of the body, namely the hands, feet, face, and scalp.

[0016] They can occur particularly on areas subjected to certain daily or frequently repeated hygiene practices such as shaving, hair removal, cleansing with toiletries or household products, the application of adhesives (bandages, patches, prosthesis fixation) or in the case of sporting, professional, or simply lifestyle-related activities and the use of clothing, tools, or equipment that generates localized friction. They can also be amplified by psychological stress.

[0017] These sensations of skin discomfort affect all people, and in particular: - people with so-called "fragile" or "delicate" and vulnerable skin that quickly becomes unbalanced during large variations in temperature or relative humidity (for example, the case of baby skin); - People with so-called "fragile" skin, including in particular: (i) people whose protective hydrolipidic film composed of sweat, sebum and natural moisturizing factors is becoming less abundant, as is the case for people over 60 years of age and especially in the context of old age (at least 75 years); (ii) persons whose hydrolipidic film composition is altered.

[0018] We can also talk about people with “aggressed” skin for shaved skin for example.

[0019] One of the critical steps in the terminal differentiation process of the stratum comeum is the cross-linking of the protein precursors of the stratum corneum (SC). This phenomenon plays an essential role in the development and maintenance of skin cohesion, physical properties of the skin such as the barrier function, and is a crucial step in the terminal differentiation process mentioned above.

[0020] Conventionally used moisturizing agents, such as humectants, moisturizing polymers, or oily substances like petroleum jelly, temporarily modify the surface properties of the skin. These agents can lead to mechanical softening of the stratum comeum, an increase in its hydration level, and / or an improvement in the skin's microrelief through the formation of a film on the skin's surface.

[0021] However, these effects are not necessarily very long-lasting. Moreover, these active ingredients can be removed by cleaning actions.

[0022] To overcome these drawbacks, it is interesting to turn to active ingredients that have a lasting beneficial action over time and are not affected by cleaning by acting on biological pathways, for example by modulating the expression of certain key biological markers in alterations of the barrier function.

[0023] It is known that an altered epidermal barrier leads to the secretion by keratinocytes of chemokines such as TSLP: (Thymia Stromal LymphoPoietin) which is known to be a key chemokine for keratinocyte communication by its ability to induce itching by directly activating certain types of neurons (TRPA-1+) as well as type 2 immune responses involved in atopic dermatitis.

[0024] In addition, other molecules are involved in this response process following barrier alteration, such as the MCP-1 and MIP-1 proteins involved in inflammatory processes in type 2 immune responses, particularly in Patients with atopic dermatitis have significantly elevated levels of these interleukins (Kaburagi et al., Arch Dermatol Res. 2001 Jul;293(7):350-5), as do the cytokines interleukin-1 alpha (IL-1A) and interleukin-29 (IL-29), which are involved in general inflammatory mechanisms (Malik and Kanneganti, Immunol Rev. 2018 Jan;281(1):124-137). IL-29 can be regulated by IL-4, which is present in type 2 immune responses and atopic dermatitis (Megjugorac et al., Blood. 2010 May 27;115(21):4185-90). These two interleukins enhance the skin barrier's ability to respond to external aggressions.

[0025] Thus, there is a need to identify new assets that can reduce the expression of these markers.

[0026] By identifying these new assets, we therefore seek to: - to prevent a decrease in and / or strengthen the skin barrier function, particularly in dry skin; and / or - to prevent and / or reduce sensations of skin discomfort, tingling, tightness, burning and itching, particularly in people with sensitive, fragile, weakened or delicate skin (for example, babies or people aged 60 and over, and especially people aged 75 and over), or people whose hydrolipidic film composition is altered, and / or - to improve the skin barrier function, particularly of atopic skin, and / or to prolong the phases of remission between acute attacks of this type of condition.

[0027] There is also a need for an active ingredient that allows the skin, in particular dry and / or sensitive and / or atopic skin, to maintain its barrier function.

[0028] There is also a need for an active ingredient to improve skin hydration.

[0029] There is also a need for active ingredients to improve the quality and / or complexion of skin, in particular the quality and / or complexion of sensitive skin; and / or to prevent and / or treat skin disorders associated with sensitive skin, in particular chosen from tightness, tingling, burning and / or itching.

[0030] There is also a need for active ingredients enabling the prevention and / or treatment of pruritus and / or inflammation of an individual's skin, in particular inflammation of skin affected by a dermatological disorder chosen from the group consisting of atopic dermatitis or eczema, psoriasis, prurigo nodularis, seborrheic dermatitis, acne, folliculitis and rosacea, or by a dermatological disorder following exposure of the skin to pollutants and / or UV radiation. Description of the invention

[0031] The present invention aims to solve the aforementioned technical problems.

[0032] Indeed, the inventors have now discovered that indole-3-pyruvic acid, in a cutaneous model of atopic dermatitis, significantly reduces the production of the chemokine TSLP, the cytokines IL-1a, IL-29, as well as the proteins MCP-1 and MlP-1a. Summary of the invention

[0033] Thus, according to a first aspect, the present invention relates to the cosmetic, in particular topical, non-therapeutic use of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent a decrease in the skin barrier function and / or strengthen the skin barrier function in an individual, in particular of dry skin.

[0034] According to a second aspect, the present invention relates to the cosmetic, in particular topical, non-therapeutic use of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent and / or treat atopic dermatitis or eczema.

[0035] According to a third aspect, the present invention relates to the cosmetic, in particular topical, non-therapeutic use of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent and / or treat a skin disorder of sensitive skin, in an individual.

[0036] Such a skin disorder may include a feeling of discomfort, and in particular tightness, tingling, burning and / or itching.

[0037] According to a fourth aspect, the present invention relates to the cosmetic use, in particular topical, of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent and / or treat pruritus and / or inflammation of the skin of an individual.

[0038] In particular, an individual may experience itching and / or inflammation of the skin: - in a dermatological disorder chosen from the group consisting of atopic dermatitis or eczema, psoriasis, prurigo nodularis, seborrheic dermatitis, acne, folliculitis, and rosacea; or - in a dermatological disorder following exposure of the skin to pollutants and / or UV rays.

[0039] Finally, the invention also relates to a non-therapeutic cosmetic process for the care of keratinous materials, preferably of the skin, comprising the application topical on these keratinous materials of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts.

[0040] A composition implemented according to the invention can be applied to fragile, weakened, dry, atopic and / or sensitive skin.

[0041] A composition implemented according to the invention can in particular be adapted for topical administration.

[0042] Other features, aspects and advantages of the invention will become apparent from the detailed description that follows. Detailed description Composition implemented according to the invention

[0043] A composition implemented according to the invention is preferably cosmetic.

[0044] A composition implemented according to the invention is preferably adapted to a topical application on keratinous materials, particularly on the skin, and therefore includes a physiologically acceptable medium, i.e. compatible with the skin.

[0045] By "cosmetic," we mean a composition compatible with keratinous materials, in particular skin, mucous membranes, and hair. The composition implemented according to the invention is non-therapeutic.

[0046] By "keratinous materials", we mean in particular the skin, mucous membranes, fibers, eyelashes and hair appendages.

[0047] By "skin" we mean the entire skin of the body, and preferably the skin of the face, scalp, décolletage, neck, arms and forearms, or even more preferably, the skin of the face (in particular the forehead, nose, cheeks, chin), décolletage and neck.

[0048] A composition implemented according to the invention preferably comprises a cosmetically acceptable medium, that is to say, one which has a pleasant colour, odor and feel and does not generate unacceptable discomforts, such as tingling, pulling, which may deter the user from applying this composition.

[0049] As used herein, the terms "treat" and "treatment" are intended to refer to the alleviation of symptoms associated with a specific disorder or condition and / or the elimination of said symptoms as well as the complete disappearance of the disorder or condition in question.

[0050] In the context of the present invention, the terms "prevent" and "prevention" refer to the reduction to a lesser degree of the risk or probability of occurrence of a given phenomenon.

[0051] A composition implemented according to the present invention thus makes it possible to confer beneficial properties for the skin, especially in a lasting way, in particular: effective barrier function; moisturizing effect; skin elasticity and smooth texture; surface morphology with low roughness, good tissue cohesion, good stratum corneum thickness and improved visual appearance of the skin.

[0052] In particular, a composition implemented according to the invention can be used on the fragile, weakened, dry, atopic and / or sensitive skin of an individual.

[0053] A recent epidemiological study of adult subjects from different countries (Haftek et al., Clin Cosmet Investig Dermatol. 2013; 6: 289-294) established that the concept of "fragile skin" resonated strongly with the populations studied. "Fragile skin" can be defined as skin with intrinsic fragility, making it more susceptible to all kinds of aggressions than non-fragile skin.

[0054] Generally speaking, fragile skin exhibits a disruption of its barrier function, resulting in increased permeability and therefore greater reactivity to stress or environmental aggressions compared to "normal" (non-fragile) skin. This type of skin is thus less resistant to stress or environmental aggressions. In addition to the dysfunction of the barrier function, these stresses can also lead to skin inflammation. Finally, fragile skin is also slower to recover its baseline state once exposed to such conditions.

[0055] Fragile skin is said to be constitutionally fragile, and corresponds for example to a baby's skin, the skin of an elderly person, or the skin of fragile areas of the body (eyelids, face ...).

[0056] Fragile skin is defined as fragile skin that is either "environmental" or "pathological." "Environmental" fragile skin includes skin that has been damaged by climatic stress (heat, cold, dryness, etc.), mechanical stress (friction, etc.), physical stress (UV radiation, lasers, etc.), or chemical stress (surfactants, solvents, etc.). "Pathological" fragile skin includes skin affected by conditions such as atopic dermatitis or eczema, psoriasis, prurigo nodularis, seborrheic dermatitis, acne, folliculitis, and / or rosacea.

[0057] By "atopic skin" we mean here a patient's skin having the same physiological and molecular characteristics as a patient's skin suffering from atopic dermatitis in particular having pruritus, inflammation, these manifestations being chronic and interspersed with periods of remission.

[0058] The expression "skin disorder" covers sensations of discomfort as well as temporary visible and unsightly skin signs that may affect the same subject.

[0059] Generally speaking, sensitive skin is defined by a particular skin reactivity. This skin reactivity is generally manifested by the appearance of signs of discomfort in response to the subject coming into contact with an element The trigger can have various origins. It may be the application of a cosmetic product to the surface of sensitive skin, the consumption of food, exposure to sudden temperature changes, air pollution, and / or ultraviolet or infrared radiation. The appearance of these signs of discomfort, which occur within minutes of contact with the trigger, is one of the essential characteristics of sensitive skin. These are essentially dysesthetic sensations. Dysesthetic sensations are defined as sensations in a specific area of ​​skin, such as tingling, tightness, burning, and / or itching.

[0060] These subjective signs most often exist in the absence of visible signs such as redness and desquamation.

[0061] "Sensitive skin" will therefore experience sensations of discomfort much more quickly and frequently than other skin types.

[0062] Dry skin feels rough to the touch and is covered with scales, manifesting primarily as a sensation of tightness and / or tension. Dry skin is indeed generally accompanied by desquamation. Physiologically, dry skin is often associated with a decrease in skin hydration levels and an alteration of the barrier function, measured by transepidermal water loss. Sensorially, it is characterized by sensations of tightness and / or skin tension.

[0063] Dry skin, also known as "xerosis", can appear at any age, and is not related to a pathological condition.

[0064] A composition according to the invention thus proves to be particularly effective in treating tightness, tingling, burning and / or itching, especially associated with fragile, weakened, dry, atopic and / or sensitive skin, in physiologically restoring a suitable state of hydration to the stratum comeum, in restoring an altered, and in particular thinned, thickness of the stratum comeum of the skin, in improving the comfort of fragile, weakened, dry, atopic and / or sensitive skin, or in combating the dull and / or atonal appearance of such skin.

[0065] As previously stated, a composition according to the invention comprises indole-3-pyruvic acid, one of its isomers or one of its salts.

[0066] Indole-3-pyruvic acid has the following formula I:

[0067] [Chem.l]

[0068] The term "salt" of an indole according to the invention means a salt formed by an inorganic or organic acid or an inorganic or organic base.

[0069] Examples of acid salts include sulfate, citrate, acetate, oxalate, chloride, bromide, iodide, nitrate, bisulfate, phosphate, isonicotinate, lactate, salicylate, citrate, tartrate, oleate, tannate, pantothenate, bitartrate, ascorbate, succinate, maleate, gentisinate, fumarate, gluconate, glucuronate, saccharate, formate, benzoate, glutamate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate and p-toluenesulfonate (i.e., 1,1'-methylene-bis-(2-hydroxy-3-naphthoate).

[0070] Examples of base salts include alkali metal hydroxides such as sodium, potassium and lithium; alkaline earth metal hydroxides such as calcium and magnesium; hydroxides of other metals, such as aluminium and zinc; ammonia and organic amines such as unsubstituted or hydroxysubstituted mono-, di- or tri-alkylamines; dicyclohexylamines; tributylamines; pyridine; N-methyl-N-ethylamine; diethylamine; triethylamine; mono-, bis- or tris-(2-hydroxy-alkylamines) such as mono-, bis- or tris-(2-hydroxyethyl)amine, 2-hydroxy-tert-butylamine, tris-(hydroxymethyl)methylamine, N,N-di-alkyl-N-(hydroxyalkyl)-amines, such as N,N-dimethyl-N-(2-hydroxyethyl)amine or tri-(2-hydroxyethyl)amine; N-methyl-D-glucamine; and amino acids such as arginine and lysine.

[0071] A salt of indole-3-pyruvic acid according to the invention is preferably a base salt, and in particular a sodium or potassium salt.

[0072] A composition implemented according to the invention may comprise a content of indole-3-pyruvic acid, in one of its isomers or in one of its salts, of at least 0.0001% by weight relative to the total weight of the composition, preferably a content of between 0.0001% and 5% by weight, more preferably a content of between 0.001% and 1% by weight, even better a content of between 0.001% and 0.01% by weight relative to the total weight of the composition.

[0073] A composition implemented according to the invention may further comprise at least one adjuvant selected from the group consisting of liquid, pasty, or solid fats; organic solvents selected from linear or branched C1-C6 monoalcohols such as ethanol, isopropanol, tert-butanol; polyols such as glycerol, propylene glycol, pentylene glycol, capylyl glycol, hexylene glycol (or 2-methyl-2,4-pentanediol) and polyethylene glycols; polyol ethers such as dipropylene glycol monomethyl ether; ionic or non-ionic, hydrophilic or lipophilic thickeners; softeners; humectants; emollients; opacifiers; stabilizers; silicones; antifoaming agents; perfumes; preservatives; anionic, cationic, non-ionic, zwitterionic or amphoteric surfactants; fillers; polymers; propellants; alkalizing or acidifying agents; and mixtures thereof.

[0074] Such an adjuvant may represent from 0.01% to 20%, preferably from 0.1% to 10% and better still, from 1% to 5% by weight, relative to the total weight of the composition.

[0075] Of course, a person skilled in the art will take care to choose this or these adjuvants and / or their quantity in such a way that the advantageous properties of indole-3-pyruvic acid, one of its isomers or one of its salts of the composition implemented according to the invention are not, or substantially not, altered by the envisaged addition.

[0076] Preferably, a composition implemented according to the invention may include water.

[0077] In particular, a composition implemented according to the invention may comprise from 1% to 95% by weight, preferably from 20% to 80% by weight of water, even better from 30% to 60% by weight, relative to the total weight of the composition.

[0078] The pH of a composition implemented according to the invention is advantageously less than or equal to 8, preferably from 4 to 7, even better from 5.5 to 6.5.

[0079] Advantageously, the composition implemented according to the invention may comprise one or more water-miscible organic solvents.

[0080] By "water miscible solvent" according to the present invention, we mean a liquid compound at room temperature and miscible with water having in particular a miscibility in water greater than 50% by weight at 25 °C and atmospheric pressure.

[0081] Water-miscible organic solvents can be selected from linear or branched C1-C6 monoalcohols such as ethanol, isopropanol, tert-butanol; polyols such as glycerol, propylene glycol, pentylene glycol, caprylyl glycol, hexylene glycol (or 2-methyl-2,4-pentanediol), and polyethylene glycols; polyol ethers such as dipropylene glycol monomethyl ether; and mixtures thereof.

[0082] These water-miscible organic solvents can be present in a composition implemented according to the invention at a concentration ranging from 0.01% to 20% by weight, preferably from 0.1% to 10% by weight and even better, from 1% to 5% by weight, relative to the total weight of the composition.

[0083] The composition implemented according to the invention may further comprise at least an additional cosmetic active ingredient.

[0084] This may in particular include at least one active ingredient for the care of fragile, weakened, atopic and / or sensitive skin.

[0085] The term "additional active ingredient" is meant, within the context of the present invention, as a compound which has, by itself, i.e., not requiring the intervention of an external agent to activate it, a biological activity which may be, in particular: - a soothing or anti-irritant activity, and / or - a moisturizing activity; and / or - an emollient activity.

[0086] The additional active ingredient usable in the compositions implemented according to the invention can in particular be chosen from humectants such as glycerol and / or urea, emollients such as petroleum jelly, anti-irritants, and mixtures thereof in all proportions.

[0087] The additional active ingredient used in the composition implemented according to the invention can represent from 0.0001% to 20%, preferably from 0.01% to 10% and even better, from 0.01% to 5% by weight, relative to the total weight of the composition.

[0088] Of course, a person skilled in the art will take care to choose this or these possible additional compounds and / or their quantity in such a way that the advantageous properties of the composition implemented according to the invention are not, or substantially not, altered by the envisaged addition.

[0089] A composition implemented according to the invention can be presented in all the pharmaceutical forms normally used in the cosmetic field, and in particular all the pharmaceutical forms normally available for the chosen method of administration.

[0090] The support can be of various kinds depending on the type of composition considered.

[0091] The compositions according to the invention can be in any form Lenics are classically used for topical application, particularly in the form of aqueous solutions, hydroalcoholic solutions, oil-in-water (O / W) or water-in-oil (W / O) emulsions, or multiple emulsions (triple: W / O / W or W / O / O), aqueous gels, or dispersions of an oil phase in an aqueous phase using spherules. These spherules may be ionic and / or non-ionic lipid vesicles (liposomes, niosomes, oleosomes). These compositions are prepared according to standard methods.

[0092] A composition implemented according to the invention is preferably adapted for topical administration.

[0093] With regard more specifically to compositions intended for topical administration, i.e. on the skin, these may be aqueous, hydroalcoholic or oily solutions, dispersions of the type of solutions or dispersions of lotion or serum type, liquid or semi-liquid consistency emulsions such as milk, suspensions or emulsions such as cream, aqueous or anhydrous gel, microemulsions, microcapsules, microparticles, or vesicular dispersions of ionic and / or non-ionic type.

[0094] A composition used according to the invention may advantageously comprise at least one liquid fat.

[0095] By "liquid fat" is meant a compound having a melting point below about 30-35 °C, as opposed to solid fats, such as waxes, which have a melting point above about 50 °C.

[0096] Examples of oils that can be used in the composition of the invention include: - hydrocarbon oils of animal origin; - hydrocarbon oils of vegetable origin, - synthetic esters and ethers, particularly of fatty acids, such as oils with formulas R'COOR2 and R'OR2 in which R' represents the remainder of a fatty acid containing 8 to 29 carbon atoms, and R2 represents a hydrocarbon chain, branched or unbranched, containing 3 to 30 carbon atoms; - linear or branched hydrocarbons, of mineral or synthetic origin; - fatty alcohols having from 8 to 26 carbon atoms; - partially hydrocarbon and / or silicone-based fluorinated oils; - silicone oils; - their mixtures.

[0097] The term hydrocarbon oil in the list of oils cited above means any oil consisting mainly of carbon and hydrogen atoms, and possibly ester, ether, fluorine, carboxylic acid and / or alcohol groups.

[0098] Other fatty substances that may be present in the oily phase include, for example, fatty acids comprising 8 to 30 carbon atoms; waxes; silicone resins; and silicone elastomers.

[0099] These fats can be chosen in a variety of ways by a person skilled in the art in order to prepare a composition having the desired properties, for example of consistency or texture.

[0100] According to a particular embodiment of the invention, the composition according to the invention is a water-in-oil (W / O) or oil-in-water (O / W) emulsion. The proportion of the oil phase of the emulsion can range from 5 to 90% by weight, and preferably from 5 to 60% by weight relative to the total weight of the composition. Emulsions generally contain at least one emulsifier selected from amphoteric, anionic, cationic, or nonionic emulsifiers, used alone or in mixtures, and optionally a co-emulsifier. The emulsifiers are selected from appropriate method depending on the emulsion to be obtained (W / O or W / O).

[0101] The emulsifier and co-emulsifier are generally present in the composition, in a proportion ranging from 0.3 to 30% by weight, and preferably from 0.5 to 20% by weight relative to the total weight of the composition.

[0102] For W / O emulsions, dimethicone copolyols and alkyl-dimethicone copolyols can be cited as examples of emulsifiers. A crosslinked solid organopolysiloxane elastomer comprising at least one oxyalkylated group can also be used as a surfactant in W / O emulsions.

[0103] For O / W emulsions, non-ionic emulsifiers can be cited as examples.

[0104] Preferably, a composition implemented according to the invention is distinguished from compositions intended primarily for detergent purposes with respect to skin, hair and / or mucous membranes, such as soaps, shampoos and shower gels for washing and / or cleaning.

[0105] More particularly, a composition implemented according to the invention may be intended for topical application and preferably may be in the form of an emulsion, preferably an oil-in-water emulsion. Preferably, such an emulsion is not intended to be rinsed off after application.

[0106] A composition implemented according to the invention may alternatively have the form of a face and / or body care or makeup product, and be packaged for example as a cream in a jar or as a fluid in a tube or pump bottle or dropper bottle.

[0107] The ingredients are mixed before shaping, in the order and under conditions easily determined by those skilled in the art. Uses and processes

[0108] As previously mentioned, according to one of its aspects, the present invention relates to the cosmetic, in particular topical, non-therapeutic use of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent a decrease in the skin barrier function and / or to strengthen the skin barrier function in an individual, in particular of dry skin, in particular to improve skin hydration.

[0109] It also relates to the cosmetic use, in particular topical, of a composition comprising, in a physiologically acceptable environment, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent and / or treat atopic dermatitis or eczema.

[0110] The present invention also relates to the cosmetic, particularly topical, non-therapeutic use of a composition comprising, in a physiological medium legally acceptable, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent and / or treat a skin disorder of sensitive skin, in an individual.

[0111] The present invention also relates to a non-therapeutic cosmetic process for the care of keratinous materials, in particular of the skin, comprising the topical application on these keratinous materials of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts.

[0112] The skin in particular concerned by such a process, and thus the skin on which a composition implemented according to the invention is applied, may preferably be fragile, weakened, dry, atopic and / or sensitive skin.

[0113] As previously stated, a composition implemented in a process of the present invention composition is preferably adapted for topical administration.

[0114] The cosmetic uses, methods and processes considered according to the invention are non-therapeutic.

[0115] The cosmetic uses and processes of the invention are preferably implemented by topically administering a composition according to the invention.

[0116] Topical administration consists of the external application to the skin of cosmetic compositions according to the usual techniques for using these compositions.

[0117] By way of illustration, the cosmetic use or process according to the invention can be implemented by topical application, for example daily, of at least one composition according to the invention, which can be, for example, formulated as a cream, gel, serum, lotion, emulsion or cleansing milk, preferably in the form of an emulsion.

[0118] The application can be repeated for example 1 to 2 times daily over a day or more and generally over a prolonged period of at least 4, or even 4 to 15 weeks, with where appropriate one or more periods of interruption.

[0119] According to one embodiment, the application is daily (once a day) and generally over a prolonged period of at least 4, or even 4 to 15 weeks, with, where appropriate, one or more periods of interruption.

[0120] According to one embodiment, the cosmetic treatment process according to the invention may comprise a single application.

[0121] Throughout the description, including the claims, the expressions "between ... and ..." and "ranging from ... to ..." shall be understood to include bounds, unless otherwise specified.

[0122] The following examples illustrate the present invention without limiting its scope.

[0123] In the examples, unless otherwise indicated, the temperature is ambient temperature (20°C), expressed in degrees Celsius, and the pressure is atmospheric pressure. Examples

[0124] Example: Study of the anti-pruritic and anti-inflammatory effect of indole-3-pyruvic acid (H3P) A / - MATERIALS AND METHODS Culture upon thawing in T75 flasks 3T3 cell thawing

[0125] [Tables 1] Product Supplier Reference Rock Inhibitor Y27632 (10mM) Sigma Y0503 Culture Medium G7F Episkin GR7F+

[0126] Table 1

[0127] 3T3 fibroblasts (ATCC, CRL-1658), used as feeders for keratinocytes, were initially cultured in DMEM (Ref 12491015, ThermoFisger) and treated with a 0.5 mg / mL solution of mitomycin (Sigma, M4287) before freezing. The mitomycin-treated 3T3s were then seeded at 2.1 million per flask in 30 mL of G7 and incubated in an oven at 37°C, 5% CO2 (2-3 hours).

[0128] Thawing of primary normal human epidermal keratinocyte (NHEK) cells collected from foreskins of healthy subjects obtained after plastic surgery at Alphenyx (France).

[0129] The NHEKs are thawed and inoculated at 0.15 million in flasks. All of the medium used to inoculate the 3T3ms is aspirated, then 35 mL of G7F + Y27632 medium (see below) is dispensed into each flask.

[0130] 65pL of cell suspension at 0.15 million NHEK are added to each Flask, followed by an incubation step in an oven at 37°C, 5% CO2. The medium is changed at 48h with 10 pM of G7F + Y27632 medium. Passage through a 48-well plate for stimulation

[0131] [Tables2] Product Supplier Reference Rock Inhibitor Y27632 (10mM) Sigma Y0503 KGM gold Lonza 00192060 TNS Promocell C-41120 Tryple express Gibco Thermofisher 10718463

[0132] Table 2

[0133] When the flasks with 3T3 feeder are at 80-90% confluence, 50,000 NHEKs are inoculated into 48-well plates with 1 mL of KGM gold medium without hydrocortisone and 1 mL of BPE (bovine pituitary extract) (instead of the 2 mL contained in the KGM gold kit supplements); Y27632 lOpM. This is followed by an incubation step in an oven for 72 hours at 37°C, 5% CO2.

[0134] After 72h, an exposure step to a stimulation cocktail as defined below is implemented in order to induce a phenotype similar to that observed in patients with atopic dermatitis in chemokines produced. Stimulation cocktail:

[0135] - Poly(I:C): 1 mg / mL (use at 10 pg / mL in the well) ref P9582 Sigma; and - IL-4: 5 pg / mL (use at 50 ng / mL in the well) ref 204-IL rndsystems; and - IL-13: 5 pg / mL (use at 50 ng / mL in the well) ref 213-ILB / CF rndsystems; and - TNFα: 5 pg / mL (used at 10 ng / mL in the well) ref 210-TA / CF rndsystems. Molecules of interest:

[0136] The various molecules of interest are added to the KGM gold culture medium: - IALD ref: 129445 Sigma: stock solution 10 mg / mL in DMSO diluted in the culture medium to the final concentration of 10 pg / mL and 25 pg / mL; or - FICZ ref: SML1489 Sigma: stock solution 0.5 mg / mL in DMSO diluted in the culture medium to a final concentration of 0.05 and 0.1 pg / mL; or - I3P ref 286281 Sigma: stock solution 10 mg / mL in DMSO diluted in culture medium to the final concentration of 10 pg / mL and 25 pg / mL.

[0137] Measurement of chemokines in the supernatant after 48 hours of culture

[0138] Use of Meso Scale Discovery technology for the measurement of chemokines in culture supernatants following the manufacturer's instructions.

[0139] [Tables3] Product Reference + Supplier: U-PLEX Metabolic Group 1 (hu) Assays, SECTOR (1 PL), MSD Meso Scale Discovery

[0140] Table 3 Statistical analysis

[0141] All experiments were performed with at least three biological replicates. Data are presented as mean ± SEM. GraphPad Prism (version 7.0; GraphPad Software, La Jolla, California) was used. Data were analyzed with the test One-way ANOVA followed by Dunnett's multi-comparison test. Results are considered statistically significant when p < 0.05. B / - RESULTS

[0142] The anti-pruritic effect of indole-3-pyruvic acid and comparators (Indole-3-Aldehyde (IALD) and FICZ (5,1 l-Dihydro-indolo[3,2-b]carbazole-6-carboxaldehyde, 6-Formylindolo[3,2-b]carbazole)) on 3D models reproducing Atopic Dermatitis was studied.

[0143] FICZ is a positive anti-pruritus and anti-inflammation control based on literature.

[0144] LTALD is also a positive control. Indeed, in the study by Yu et al. (J Allergy Clin Immunol, 2019 Jun;143(6):2108-2119.el2), topical application of IALD reduced skin inflammation in a mouse model of dermatitis-like.

[0145] The results in Tables 4, 5 and 6 below are expressed as a percentage difference from the stimulated control.

[0146] [Tables4] IALD 10 pg / ml IALD 25 pg / ml Mean Standard deviation p-value Mean Standard deviation p-value TSLP -16.38184 2.33661221 0.2201 22.7388594 6.73744044 0.0514 MCP-1 -14.247764 15.8621346 0.7414 -4.7779716 10.0122588 0.9961 IL-1a -46.110998 4.06096458 0.0009 -51.824122 2.01626723 0.0003 MlP-1a -7.3177166 13.6181252 0.9958 72.9587581 18.0260873 0.0035 IL-29 -29.474118 9.86424417 0.357 -8.9199235 7.81179246 0.9885

[0147] Table 4

[0148] [Tables5] FICZ 0.05 pg / ml FICZ 0.1 pg / ml mean standard deviation p-value mean standard deviation p-value TSLP -40.646136 2.79184986 0.0006 -50.780226 2.69490693 <0.0001 MCP-1 -56.546417 9.12736272 0.0032 -51.485305 9.09595406 0.0067 IL-1a -67.017405 3.26210117 <0.0001 -69.590533 4.77972139 <0.0001 MlP-1a -96.486222 0.6368101 0.0003 -96.408505 0.6979015 0.0003 IL-29 -71.283831 3.15839094 0.0033 -77.919043 2.41739189 0.0015

[0149] Table 5

[0150] [Tableauxô] Indole-3-pyruvic acid 10 pg / ml Indole-3-pyruvic acid 25 pg / ml Mean Standard deviation p-value Mean Standard deviation p-value TSLP -46.987218 6.69572694 0.0001 -70.858371 3.15223595 <0.0001 MCP-1 -61.493266 7.5912511 0.0016 -72.995249 4.7522178 0.0003 IL-1a -57.775648 1.78526117 0.0001 -53.358746 5.56352483 0.0002 MlP-1a -94.758177 1.39000401 0.0003 -96.959254 0.566884 0.0003 IL-29 -76.219802 4.89726954 0.0018 -89.398342 1.38461009 0.0004

[0151] Table 6

[0152] These tables represent the percentage expression levels of TSLP, MCP-1, IL-1a, MlP-1a, and IL-29 relative to the stimulated control in keratinocyte culture medium 48 hours after stimulation. The p-values ​​are calculated relative to the stimulated control.

[0153] TSLP: (Thymia Stromal LymphoPoietin) is a key chemokine for keratinocyte communication by its ability to induce itching by directly activating certain types of neurons (TRPA-1+) as well as type 2 immune responses involved in atopic dermatitis.

[0154] MCP-1 and MlP-la are proteins involved in inflammatory processes in type 2 immune responses, particularly in patients with atopic dermatitis where they are found to be significantly increased (Kaburagi et al., Arch Dermatol Res. 2001 Jul;293(7):350-5).

[0155] It appears from these tables a significant decrease in the production of the chemokines TSLP, IL-la, and IL-29 as well as the proteins MCP-1 and MlP-la for 1T3P and FICZ, a decrease which is not observable with 1TALD.

[0156] In conclusion, all these results demonstrate that I3P has a very good ability to restore the barrier function of the epidermis, especially compared to 1TALD.

Claims

Demands

1. Composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, for use in the prevention and / or treatment of atopic dermatitis or eczema.

2. Cosmetic use, including topical, non-therapeutic use of a composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, to prevent and / or treat a skin disorder of sensitive skin in an individual, the skin disorder being a sensation of discomfort, including tightness, tingling, burning and / or itching.

3. Composition comprising, in a physiologically acceptable medium, indole-3-pyruvic acid, one of its isomers or one of its salts, for use in the prevention and / or treatment of pruritus of the skin of an individual.

4. Composition for its use according to claim 3, wherein pruritus at the level of the skin of an individual is present: - in a dermatological disorder selected from the group consisting of atopic dermatitis or eczema, psoriasis, prurigo nodularis, seborrheic dermatitis, acne, folliculitis and rosacea; or - in a dermatological disorder following exposure of the skin to polluting agents.

5. Use according to claim 2, or composition for its use according to any one of claims 1, 3 and 4, wherein the composition is applied to fragile, weakened, dry, atopic and / or sensitive skin.

6. Use according to claim 2, or composition for its use according to any one of claims 1 and 3 to 5, wherein the composition comprises a content of indole-3-pyruvic acid, in one of its isomers or in one of its salts, of at least 0.0001% by weight relative to the total weight of the composition, preferably a content of between 0.0001% and 5% by weight, more preferably a content of between 0.001% and 1% by weight, even better a content of between 0.001% and 0.01% by weight relative to the total weight of the composition.

7. Use according to claim 2, or composition for its use according to any one of claims 1 and 3 to 6, wherein the composition further comprises at least one adjuvant selected from the group consisting of liquid, pasty or solid fats; organic solvents selected from linear or branched C1-C6 monoalcohols such as ethanol, isopropanol, tert-butanol; polyols such as glycerol, propylene glycol, pentylene glycol, capylyl glycol, hexylene glycol (or 2-methyl-2,4-pentanediol) and polyethylene glycols; polyol ethers such as dipropylene glycol monomethyl ether; ionic or non-ionic, hydrophilic or lipophilic thickeners; softeners; humectants; emollients; opacifiers; stabilizers; silicones; antifoaming agents; perfumes; preservatives; anionic, cationic, non-ionic, zwitterionic or amphoteric surfactants;fillers; polymers; propellants; alkalizing or acidifying agents; and mixtures thereof.

8. Use according to claim 2, or composition for its use according to any one of claims 1 and 3 to 7, the composition being adapted for topical administration.