Topical cosmetic composition for sensitive skin

Abstract

The invention relates to the field of cosmetics. The invention relates more particularly to a method for the cosmetic care of sensitive skin, characterized in that it comprises the application to said sensitive skin of a composition comprising flocculosine as active agent, to obtain a soothing effect by stimulating the production of beta-endorphin and / or the expression of the CB2 receptor by the cells of said sensitive skin, said composition being optionally incorporated into a cosmetically acceptable excipient. The invention also relates to the non-therapeutic use of flocculosine to stimulate the production of beta-endorphin and / or the expression of the CB2 receptor by skin cells. Figure to be published with the abstract: Figure 2

Description

Title of the invention: Topical cosmetic composition for sensitive skin FIELD OF THE INVENTION The technical sector of the present invention relates to cosmetics. More particularly, the technical sector relates to the cosmetic treatment of sensitive skin. STATE OF THE ART The microscopic fungus Pseudozyma flocculosa was first discovered in 1988 on the surface of clover leaves. (Traquair et al. (1988). This fungus has the particularity of living epiphytically on the surface of certain plants such as clover while protecting this plant against pathogen aggression by producing a molecule called flocculosin (Cheng et al. ,2003). [Chem.l]

[0004]

[0005] Molecular structure of flocculosin Flocculosin (according to the nomenclature of the International Union of Pure and Applied Chemistry: 16-[(2R,3R,4R,5S,6R)-5-[(2S,3R,4S,5R,6R)-4-acetyloxy-5-hydroxy-6-(hydroxymethyl)-3-(3-hydroxyoctanoyloxy)oxan-2-yl]oxy-6-(acetyloxymethyl)-3,4-dihydroxyoxan-2-yl]oxy-3,15-dihydroxyhexadecanoic acid, compound referenced in the PubChem database under the number: 11679497), is a glycolipid of 854 Daltons and is mainly known today for its antibacterial properties. It can naturally protect certain plants against the attack of pathogenic microorganisms. This molecule produced by nature is therefore particularly interesting for protecting certain plants in a completely natural way against the attack of pathogenic microorganisms.

[0006] Its antifungal activities are well documented (Mimee et al., 2005). Some antibacterial activities have also been demonstrated using this molecule (Patent WO2004007514, also B. Mimee (2008)).

[0007] This molecule, through its antibacterial properties, can find a complementary application in formulas to help fight dental caries (WO2009129525).

[0008] Completely by chance, while working on flocculosine, the applicant observed during studies on skin or scalp that this molecule had great interest for an application in the field of sensitive skin care. Currently, this problem is major worldwide on both young and mature skin. Indeed, according to sources, 45 to 60% of skins are affected by sensitivity problems.

[0009] The skin is the largest organ in our body with a surface area of 1.8 m2 and an average weight of 3 kg in an adult weighing 70 kg. Adult human skin is divided into 3 compartments: the epidermis, the dermis and the hypodermis. The epidermis is in contact with the external environment and constitutes the multi-stratified, keratinized, non-vascularized squamous epithelium; it is mainly composed of layers of keratinocytes which represent 90 to 95% of epidermal cells (Démarchez et al.: https: / / biologiedelapeau.fr / ).

[0010] The cutaneous nervous system is rich and complex with an afferent pathway and an efferent pathway, the three cutaneous compartments, hypodermis, dermis, and epidermis (except the stratum corneum), being innervated. In direct contact with the external environment, the skin is therefore a major sensory organ. Close contacts between nerve fibers and skin cells have been observed by electron or confocal microscopy. The nerve fibers of the skin produce neurotransmitters (including endorphins) and neurohormones. Epidermal and dermal cells can also produce neurotransmitters and enzymes that can degrade them; they express receptors for neurotransmitters and are therefore also sensitive to the action of neurotransmitters (Démarchez et al.: https: / / biologiedelapeau.fr / ).

[0011] Connections between skin cells such as keratinocytes are therefore at the forefront of sending signals from the skin to the nervous system.

[0012] Epidermal keratinocytes communicate with sensory neurons via synaptic-like contacts. These contacts exhibit the ultrastructural characteristics and molecular characteristics of synaptic-like chemical contacts. (Misery L. et al. Keratinocytes Communicate with Sensory Neurons via Synaptic-like Contacts. Ann Neurol. 2020 Dec. 88(6):1205-1219).

[0013] Endorphins are neurotransmitters released in the brain, pituitary gland, and throughout the nervous system to combat pain and stress. Endorphins interact with opiate receptors in the brain—much like morphine and codeine—to naturally reduce the perception of pain.

[0014] Endorphins are released for example during vigorous exercise or when tasting certain foods, such as chocolate and chili peppers, or with scents such as lavender or vanilla and endorphins have incredible abilities to reduce stress and relieve pain.

[0015] Activation of the cannabinoid receptor 2 (CB2) results in the release of beta-endorphin ([3-endorphin) from keratinocytes, which then acts on primary afferent neurons to inhibit nociception (Gao F. et al., 2016).

[0016] In the context of the present invention, it has now been discovered completely by chance by the applicant that flocculosine, or an extract containing it, is capable of stimulating the production of [3-endorphin in the skin, on the one hand by stimulating the production of [3-endorphin by the keratinocytes of the skin and also by increasing the presence of CB2 receptors in the skin.

[0017] Thus, the present invention aims to stimulate the production of [3-endorphin in the skin, and in particular to stimulate the production of [3-endorphin by the keratinocytes of the skin. Another aim of the invention is to stimulate the expression of CB2 receptors in the skin.

[0018] Another aim of the present invention is the provision of a new cosmetic care method for sensitive skin, making it possible to combat skin sensitivity and discomfort reactions of sensitive skin, and thus to provide feelings of well-being and / or to have a soothing effect.

[0019] The use of flocculosine, an extract containing it or a cosmetic composition containing it constitutes a simple, reliable and reproducible solution, biological and usable on an industrial scale in the field of cosmetics in response to the aforementioned problems. Statement of the invention

[0020] As illustrated in the experimental part, the applicant has demonstrated that flocculosin, a membrane glycolipid produced naturally by the fungus Pseudozyma flocculosa, stimulates the production of beta-endorphin and the expression of the CB2 receptor by skin cells.

[0021] Thus, according to a first aspect, the invention relates to the non-therapeutic use of flocculosine to stimulate the production of beta-endorphin ([3-endorphin) and / or the expression of the CB2 receptor by skin cells.

[0022] Flocculosin used in the cosmetic field provides an effective solution to the problem of sensitive skin by allowing on the one hand a stimulation of the secretion of [3-endorphin but also an amplification of the expression of the known CB2 receptors involved in the production of [3-endorphin. In addition, flocculosin is a natural compound, synthesized without synthetic chemistry, which is of particular advantage in the field of cosmetic care, even more particularly in the care of sensitive skin.

[0023] Thus, according to a second aspect, the invention also relates to a method for the cosmetic care of sensitive skin, characterized in that it comprises the application to said sensitive skin of a composition comprising flocculosine as active agent, to obtain a soothing effect by stimulation of the production of [3-endorphin and / or the expression of the CB2 receptor by the cells of said sensitive skin, said composition optionally comprising at least one cosmetically acceptable excipient.

[0024] According to other optional features of the method, the latter may optionally include one or more of the following features, alone or in combination:

[0025] - flocculosin is included in the composition, at a concentration of between 0.5 parts per million and 25 parts per million, preferably between 1.00 parts per million and 15.00 parts per million by mass of said composition,

[0026] - flocculosin is incorporated into the composition in dissolved form in a solvent selected from: propanediol, glycerin or butylene glycol,

[0027] - the composition comprises from 0.1% to 5% by mass of a 0.50 gram preparation per liter of flocculosin,

[0028] - the preparation at 0.50 grams per liter of flocculosine is propanediol comprising 0.50 grams per liter of flocculosine,

[0029] - the composition is in the form of a cream, a balm, a lotion, of an oil, a butter or a spray,

[0030] - flocculosin is combined with another cosmetically active substance acceptable, chosen from, designated according to their INCI name: maltodextrin (and) biosaccharide gum-1; biosaccharide gum-1; aminopropanediol esters linseed oil / palm oil; biosaccharide gum-4 (and) 1,2-hexanediol; propylene glycol / water / Theobroma cocoa extract; Butylene glycol (and) water (and) Ageratum conyzoides leaf extract; or propanediol (and) water (and) Vitis vinifera grape juice extract, or mixtures thereof,

[0031] - the calming effect obtained by stimulation of the production of [3-endorphin by skin cells includes preventing and / or reducing at least one skin sensation selected from: tingling, prickling, feelings of tightness, feelings of heat or even burning sensations, itching and / or the appearance of skin redness. Brief description of the drawings

[0032] Other characteristics, advantages and details of the invention will be better understood on reading the additional description which follows in relation to the drawings in which:

[0033] [Fig-1] represents a graph illustrating the effect of flocculosine on the expression of the CB2 receptor in percentage of surface in the human epidermis (ns: not significant; Student's t-test *p<0.1; **p<0.05), and

[0034] [Fig.2] represents a graph illustrating the effect of flocculosine on the release of [3-endorphin] by human keratinocytes in monolayer culture (ns: not significant; Student's t-test *p<0.05; **p<0.01).

[0035] DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0036] “Sensitive skin” within the meaning of the invention is in particular skin that reacts to stimuli which, under normal conditions (i.e. in an individual not having sensitive skin), have no effect on other types of skin. These stimuli, which are very diverse, may be UV radiation, heat, cold, exposure to wind, temperature variations, friction, exposure to different cosmetic or chemical products (soaps, shampoo, makeup, skincare creams), certain water qualities, chemical agents (present for example in detergents), stress or emotions, hormonal states (menstrual cycle, stress, etc.), food, etc. The reaction of sensitive skin to the stimulus includes a generally unpleasant skin sensation such as tingling, prickling, feelings of tightness, feelings of heat or even burning, itching and / or the appearance of skin redness.This at least one sensation may be transient.

[0037] This unpleasant sensation or discomfort may be spontaneous, without any particular identified cause. It may also be linked to contact of the skin with a particular material, or exposure to the sun (without causing a sunburn-type burn), to wind, a chemical agent such as a detergent, a soap or any other cosmetic composition.

[0038] In a particular embodiment, the sensitive skin is skin exhibiting dehydration (for the purposes of the invention, skin exhibiting dehydration is not skin that has been burned or previously exposed to thermal or UV radiation). Indeed, skin dehydration contributes to the exacerbation of skin sensitivity.

[0039] In another particular embodiment, the sensitive skin is so-called dry or very dry skin, which is skin which has an alteration of the hydrolipidic film, (sebum), which protects the skin from external aggressions and prevents water loss. When the upper layer of the epidermis is not balanced in water and lipids, it can no longer effectively play its role as a barrier and becomes uncomfortable to varying degrees as detailed above.

[0040] In another particular embodiment, the subject having sensitive skin does not suffer from pathologies affecting his skin (such as rosacea, eczema, seborrheic dermatitis, an infection). Nevertheless, it is understood that certain skins particularly prone to triggering (but not suffering from) rosacea, eczema or dermatitis may constitute sensitive skins within the meaning of the invention.

[0041] Sensitive skin can be present on any part of the body; it can be the scalp, the skin of the face, or more precisely, the lips, or the area around the eyes, the hands, or any other region of the skin which is or is likely to be the site of a feeling of discomfort as described above.

[0042] A “soothing effect”, such as that induced by exposure to flocculosin, includes prevention, reduction or even elimination of an unpleasant sensation or discomfort such as itching, tingling, pins and needles, feelings of tightness, feelings of heat or even burning sensations.

[0043] The expression "parts per million", or ppm, as used herein, and according to the usual acceptance, means 10 6 in relative value, or 1 x 10 6, and relates, unless otherwise stated, to the mass ratios of the compounds of the preparations described.

[0044] Unless otherwise provided, mass concentrations given as a percentage are understood to be in units of mass relative to the volume of the solution (for example, in g / 1).

[0045] The “cannabinoid receptor 2” (CB2) refers to the membrane receptor encoded by the CNR2 gene (NCBI reference: Gene: 1269). This receptor, coupled to the G protein, is involved in numerous mechanisms. It is notably known to be expressed in cells of the immune system, and its activation is thought to be the cause of anti-inflammatory effects. These receptors are also involved in mediating analgesic effects in the peripheral nervous system (Gao F. et al., 2016.

[0046] The cosmetic compounds are designated here in accordance with the International Nomenclature of Cosmetic Ingredients or "INCI designation" (in English terminology, for International Nomenclature of Cosmetic Ingredients), the use of which has been obligatory in Europe to designate these compounds since 1998. The French translation of certain terms of this nomenclature is however proposed.

[0047] The present invention originates from the accidental discovery by the applicant that flocculosine induces in human skin explants an increase in the expression of CB2 as well as in the secretion of [3-endorphin by keratinocytes. Thus, flocculosine is of particular interest in the treatment of skin sensitivity because it induces i) on the one hand the secretion of [3-endorphin in the skin, [3-endorphin can therefore produce its analgesic effect locally, in the epidermis and ii) on the other hand, an increase in the expression of the CB2 receptor in the skin, the activation of which is in particular responsible for the expression of [3-endorphin by keratinocytes. Thus, an amplification of the soothing effect of flocculosine can be expected. Non-therapeutic use of flocculosin

[0048] Thus, in a first aspect, the invention relates to a non-therapeutic use of flocculosine for stimulating the production of [3-endorphin] and / or the expression of the CB2 receptor by skin cells.

[0049] As demonstrated in [Fig.l], a significant increase in CB2 expression in relation to the exposure of explants to human skin flocculosin is observed. [Fig.2] shows a dose-dependent increase in the secretion of [3-endorphin] by keratinocytes exposed to flocculosin

[0050] CB2 receptors are involved in many physiological mechanisms and their regulation in the skin is of particular interest, especially in experimental models in the cosmetic field. Also in a particular embodiment, the invention relates to the non-therapeutic use of flocculosine to stimulate the expression of the CB2 receptor in keratinocytes in vitro or ex vivo.

[0051] “Ex-vivo” includes skin explant models as illustrated in the part experimental.

[0052] “In-vitro” includes use in cultures of isolated keratinocytes.

[0053] Indeed, such use allows stimulation of the expression of CB2 for example without genetic manipulation, and therefore a study of the physiological and / or molecular mechanisms involving CB2 in the skin close to physiological conditions.

[0054] In another embodiment, this non-therapeutic use aims to obtain in vivo locally a soothing effect on the skin, in particular at the area of application of flocculosine on the skin. More particularly, the local soothing effect is felt at the level of the area for which an increase in the secretion of [3-endorphin and / or an increase in the expression of CB2 is observed.

[0055] This soothing effect is not obtained in a pathological context. Thus this soothing effect is not a treatment for a pathological condition of the skin or its symptoms. Cosmetic care process for sensitive skin

[0056] In a second aspect, the invention relates to a method for cosmetic care of sensitive skin.

[0057] In one embodiment, said method comprises applying to said sensitive skin a composition comprising flocculosine as an active agent, to obtain a soothing effect by stimulating the production of [3-endorphin and / or the expression of the CB2 receptor by the cells of said sensitive skin, said composition optionally comprising a cosmetically acceptable excipient.

[0058] In a particular embodiment, said method is implemented on skin not suffering from a specific pathology.

[0059] The flocculosin preparation can be obtained as illustrated in the experimental part. In one embodiment, the preparation contains flocculosin in a solvent such as glycerin, butylene glycol, propanediol, preferably propanediol. Indeed, propanediol is particularly suitable for flocculosin preparations.

[0060] An excipient means any substance other than the active ingredient in the composition. In a particular embodiment, the flocculosin preparation is incorporated into a cosmetic composition, which therefore comprises cosmetically acceptable excipients. In an even more particular embodiment, this composition may comprise other active ingredients.

[0061] In one embodiment of the method for caring for sensitive skin according to the invention, the composition comprising flocculosin as active agent comprises from 0.5 ppm to 25 ppm, preferably between 1.00 ppm and 15.00 ppm, even more preferably between 5.00 ppm and 10.00 ppm.

[0062] In an advantageous embodiment of the method for caring for sensitive skin according to the invention, the composition comprising flocculosin as active agent comprises between 0.1% and 5.0% by mass, between 1.0% and 4.0% by mass, or even between 2.0% and 3.0% by mass, of a solution of 0.50 g per liter of flocculosin.

[0063] In a particular embodiment, flocculosin in the method according to the invention is the only active agent of the composition.

[0064] In another embodiment, the composition comprising flocculosin as an active agent also comprises other active agents whose effects can be advantageously combined with those of flocculosin.

[0065] For example, the composition may comprise: - at least one antioxidant compound selected from: vitamin E or ascorbyl palmitate, alone or their mixtures, - Fucogel® Powder (INCI name: maltodextrin & biosaccharide gum-1), or Fucogel® (INCI name: maltodextrin & biosaccharide gum-1, or in French: maltodextrin and biosaccharide gum-1), Fugogel® is known to also have soothing properties, - Omega 3 Ceramide® Lin (INCI name: linseed oil / palm oil aminopropanediol esters), known to restore the skin's protective barrier, - Pollustop® (INCI name: Biosaccharide gum-4 (and) 1,2-hexanediol), as in example 3, which is known to form a barrier against UV rays, atmospheric and chemical pollutants, - Caophenol® (INCI name: Propylene glycol / Aqua / Theobroma cacao extract), which is known to protect the skin against urban stress, - Ageraline® (INCI name: Butylene glycol (and) Water (and) Ageratum conyzoides leaf extract, or in French: Butylene glycol (and) water (and) extract of Ageratum conyzoides leaves), or - Viniderm® (INCI name: Propanediol (and) Water (and) Vitis vinifera grape juice extract, or in French: Propanediol (and) water (and) extract of Vitis vinifera grape juice),

[0066] or one of their mixtures.

[0067] The cosmetic composition used in the process according to the invention may comprise any other compound, or excipient, usually used in cosmetic compositions such as, designated according to its INCI name: - at least one preservative, for example selected from: phenoxyethanol, ethylhexylglycerin, hexanediol alone or their mixtures - at least one texturizing agent such as: • a butter, for example chosen from, designated according to their INCI name: soybean glycerides / butyrospermum parkii (shea) / butter unsaponifiables (in French: glycerides de soja / butyrospermum parkii (karité) / unsaponifiables de beurre; Theobroma cacao (cocoa) seed butter (in French: beurre de graines de théobroma cacao (cacao)):, alone or their mixtures, • an oil, for example chosen from: Argania spinosa kernel oil; sunflower oil, raspberry seed oil, kiwi seed oil, alone or mixtures thereof, • a wax, chosen from: behenyl alcohol; sunflower wax, alone or their mixtures, or • a gelling agent, chosen from, designated according to their INCI name: hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer / aqua(water) / C 15-23 alkane / decyl glucoside D / C13-14 alkane / glycerin (or in French Copolymère d'acrylate d'hydoxyéthyle / acryloyldiméthyl taurate de sodium / aqua(eau) / alkane en Cl5-23 / D-glucoside de décyle / alkane en C13-C14 / glycerin); Sclerotium rolfssii gum; xanthan gum, alone or mixtures thereof, - at least one emollient agent, for example chosen from: dicaprylyl carbonate; ethylhexylglycerin; isocetyl stearate; sunflower wax; sunflower seed oil; caprylic / capric triglyceride; vegetable oil; passion fruit seed oil; coco-caprylate; octyldodecanol, alone or in mixtures thereof, or - at least one emulsifier, for example chosen from: polyglyceryl-3 methylglucose distearate, cetearyl olivate, sorbitan olivate, polyglyceryl-6 distearate, jojoba esters, polyglyceryl-3 beeswax, cetyl alcohol, glyceryl stearate citrate, polyglyceryl-3 diostearate, glycerin, sorbitan palmitate, sorbitol, sucrose laurate, sucrose dilaurate and sucrose trilaurate, alone or mixtures thereof,

[0068] or any other usual cosmetic excipient.

[0069] Thus, the composition comprising flocculosine as an active agent can take the form of a cream, a balm, a lotion, an oil, a butter or a spray depending, for example, on the part of the body for which it is intended, the times of day or even the external conditions to which the sensitive skin is subjected.

[0070] Other aims and advantages of the invention will appear clearly in light of the examples of embodiments of the invention given by way of illustration and without limitation.

[0071] Unless otherwise indicated, percentages are given by weight, temperatures are in degrees Celsius, and pressure is atmospheric pressure at room temperature.

[0072] Example 1: Flocculosin induces an increase in CB2 expression in the skin. Test methodology.

[0073] The test is carried out on human skin explants from an abdominoplasty of a 50-year-old Caucasian woman of phototype III (according to the Fitzpatrick classification). On day D0, the explants survived in culture medium at 37°C in a humid atmosphere, enriched with 5% CO2.

[0074] On D0, D2, D5 and D7, the placebo formula or the flocculosine preparation formulated at 2% (Table 1) were applied topically, at a rate of 2 μL per 1 cm2 of explant (“2 mg / cm2) and spread using a small spatula. The explants in the control batches received no treatment, except for renewal of the medium. The medium was renewed by half (1 mL / well) on D2, D5, D7 for all conditions. All conditions were carried out in triplicate.

[0075] [Tables 1] Tested compositions formula Composition (m / v) placebo Phase A: Phase B: - microcare PM3 at 0.5%. flocculosine Phase A: Phase B: Phase C: - 2% of a preparation at 0.5 g / l of flocculosine in propanediol.

[0076] At D0, 3 untreated explants were collected and cut in half. Half of each punch was fixed in buffered formalin solution and the other was frozen (-80°C). On day 9, 3 explants from each batch were collected and treated in the same way as at D0.

[0077] After 24 hours in buffered formalin, the samples were dehydrated and impregnated with paraffin using a Leica PEARL dehydration machine. They were assembled using a Leica EG 1160 asphalt plant. 5 μm sections were made using a Minot type microtome, Leica RM 2125 and mounted on Superfrost® histological glass slides.

[0078] For frozen explants, 7 μm sections were made using a Leica CM 3050 cryostat and mounted on Superfrost® Plus silanated histological glass slides. Microscopic observations were carried out by optical microscopy, using a Leica DMLB, Olympus BX43 or Olympus BX63 microscope. Photos were taken with an Olympus DP72 or DP74 camera and cellSens software.

[0079] Cell viability of epidermal and dermal structures was observed on paraffin sections after staining with the Masson trichrome variant of Goldner. The labeling was assessed by microscopic examination.

[0080] CB2 immunostaining was performed on frozen sections with an anti-CB2 polyclonal antibody (NSJ Bioreagents, ref. F40838) diluted 1:50 in PBS-BSA 0.3%-Tween 20 (0.05%) for 1 night at room temperature, and revealed in Alexa Fluor AF488 (Lifetechnologies, ref. Al 1008). Immunostaining was assessed by microscopic observation. CB2 image analysis was performed using cellSens software (Olympus). Area analyzed: entire epidermis. Number of images analyzed per batch: 9. Results

[0081] Viability:

[0082] On day 0, cell viability is good in the epidermis and papillary dermis. On day 9, cell viability is quite good in the epidermis and good in the papillary dermis. Treatments with the placebo formula and the one containing flocculosin did not induce any change in viability compared to the control on day 9.

[0083] CB2 marking ([Fig. 1]): - at D0, CB2 marking is present on 69.9% of the surface of the epidermis. - at D9, CB2 marking is present at 61% of the surface of the epidermis. A A non-significant decrease of 1% is observed for samples treated with the placebo formula. The formula containing flocculosine induces a significant increase of 49% in CB2 labeling on the surface of the epidermis compared to D0 and a significant increase of 50% compared to the placebo.

[0084] Example 2: flocculosine induces an increase in the production of p-endorphin in the skin. Test methodology.

[0085] Human keratinocytes obtained from a 49-year-old woman and a 39-year-old woman, respectively, were subjected to a P-endorphin release test. To carry out the experiments, these cells were cultured in a monolayer until they reached confluence.

[0086] Viability: cytotoxic effect of flocculosin on normal human keratinocytes in monolayer culture

[0087] The cells were incubated for 24 hours in the absence (control) or in the presence of increasing concentrations of the test compound. The flocculosin preparation (0.5g / l preparation of flocculosin in propanediol) was tested at 0.0003%, 0.001%, 0.003%, 0.01%, 0.03%, 0.1%, 0.3%, 1% and 3% (v / v). The flocculosin preparation was re-diluted directly into the incubation medium to reach the different concentrations described above. At the end of the incubation period, cell viability was assessed by a spectro-colorimetric method based on the measurement of alkaline phosphatase activity (Yang et al. (1996)).

[0088] Dosage of [3-endorphin:

[0089] Amantadine hydrochloride at 0.1 μM was used as a reference activator of [3-endorphin]. The cells were incubated for 24 hours in the absence (control) or presence of reference product or increasing concentrations of flocculosin (0.1% and 0.5%, v / v). Flocculosin and reference were diluted directly into the incubation medium to reach the different concentrations described above. At the end of the 24-hour incubation period, the beta-endorphin released into the culture medium was quantified using a sensitive and specific ELISA kit (supplier: Antibodies-online; reference ABIN6963481, Human beta-EP (Beta-endorphin) ELISA Kit). At the end of the incubation period, the proteins contained in the cell lysates were quantified by a spectro-colorimetric method (Bradford method).Results are expressed as picograms (pg) of [3-endorphin per milligram (mg) of total protein (mean ± standard deviation).

[0090] Statistical analysis: The level of significance between “Control” and “reference product” was assessed using a Student’s t-test (*: p<0.05). The level of significance between “Control” and “flocculosin” was assessed using a Student’s t-test (*: p<0.05; **: p<0.01). Results

[0091] Viability:

[0092] No cell viability problems were detected even at the maximum concentration of the experiment.

[0093] Dosage of [3-endorphin([Fig.2]):

[0094] Under these experimental conditions, flocculosin is able to induce the secretion of [3-endorphin in a dose-dependent manner. A strong tendency of increase in [3-endorphin secretion is observed for cells incubated with 0.1% flocculosin. A very significant increase in [3-endorphin synthesis is observed for cells incubated with 0.5% flocculosin ([Fig.2]: + 44.08% (p<0.01)). Conclusions#:

[0095] These results show in the cutaneous context a soothing activity of flocculosine, by inducing the expression of CB2 receptors and the secretion of [3-endorphin. This molecule is therefore of great interest for cosmetic applications in the field of sensitive skin.

[0096] Example 3: Examples of cosmetic compositions suitable for the process according to the invention.

[0097] Several examples of cosmetic preparations are proposed below. These formulations are particularly suitable for the care of sensitive skin.

[0098] Formulation 1: Anti-pollution micellar lotion for sensitive skin.

[0099] [Tables2] Compound Supplier INCI Names % by mass of the composition Demineralized water / AQUA (WATER) 90.1 PHENOXYETHANOL IMCD PHENOXYETHANOL 0.9 FLOCCULOSINE SOLABIA - 3.0 1.3 PROPANEDIO L COSMOS CONNECT CHE MICALS PROPANEDIOL 1.0 ORAMIX CG 110 SEPPIC CAPRYLYL / CAPRYL GLUC OSIDE AQUA (WATER) 1.0 NATPURE SOL SENSIENT COS METIC TECHN OLOGIES GLYCERIN SUCROSE LAURATE SUCROSE DILAURATE SUCROSE TRILAURATE SORBITOL 1.0 POLLUSTOP SOLABIA Group -SOLABIA AQUA (WATER) 1,2-HEXANEDIOL BIOSACCHARIDE GUM-4 3.0 TOTAL 100.0

[0100] Micellar lotions are particularly suitable for skin care and cleansing. In addition, the combination of the soothing effect of flocculosine with the protective effect of a protective compound, such as for example Pollustop®, against atmospheric, UV and / or chemical pollution which particularly attacks sensitive skin is of particular interest, because it provides on the one hand a protective barrier and on the other hand a soothing effect in prevention or during this exposure.

[0101] Formulation 2: Protective mist for sensitive skin

[0102] [Tables3] Compound Supplier INCI Name % by mass of the composition DEMINERALIZED WATER / AQUA (WATER) 96.97 PHENOXYETHANOL SAFIC-ALCAN PHENOXYETHANOL 0.90 MICROCARE EHG THOR ETHYLHEXYLGLYCERIN 0.10 FLOCCULOSIN SOLABIA PROPANEDIOL / GLYCOL IPIDS 2.00 SODIUM HYDROXIDE, SOLUTION 1% / AQUA (WATER) / SODIU M HYDROXIDE 0.03 TOTAL 100.00

[0103] Mist-type formulations are suitable for facial and / or body skin care, but also for scalp care. For example, such a mist containing flocculosine is of particular interest for soothing the skin and / or preventing itching associated with, for example, exposure to heat from drying agents, wearing a wig, hair regrowth or exposure to conditioner-type agents.

[0104] Formulation 3: Face balm for sensitive skin

[0105] [Tables4] Compound Supplier INCI Name % by mass of the composition WATER DEMINERALIS EE / AQUA (WATER) 66.07 PHENOXYETHANO L SAFIC-ALCAN PHENOXYETHANO L 0.90 TEGO CARE 450 MB EVONIK INDUST RIES POLYGLYCERYL-3 METHYLGLUCOSE DISTEARATE 3.00 LIPEXL'SENS AARHUSKARLS HAMN SOYBEAN GLYCERI DES / BUTYROSPERMUM PARKII (SHEA ) / BUTTER UNSAPO NIFIABLES 3.00 CETIOL CC BASF DICAPRYLYL CARB ONATE 5.00 CACAO BUTTER INTERCHIMIE THEOBROMA CAC AO (COCOA) SEED BUTTER 5.00 NACOL 22-98 SASOL BEHENYL ALCOHO L 2.00 HUILE D'ARGAN VI ERGE DESODORISE E BIOLOGIQUE OLVEA VEGETA BLE OILS ARGANIA SPINOSA KERNEL OIL 3,00 DUB SIS 16 STEARINERIE D UBOIS ISOCETYL STEARA TE 5,00 MICROCARE EHG THOR ETHYLHEXYLGLY CERIN 0,20 OMEGA 6 CERAMID E CARTHAME SOLABIA SAFFLOWER OIL / P ALM OIL / AMINOP ROPANEDIOL ESTE RS 0,50 GLYCERINE INTERCHIMIE GLYCERIN 3,00 SOLAGUM TARA SEPPIC CAESALPINIA SPIN OSA GUM 0,15 SENSOGEL NOVUS APPLECHEM HYDROXYETHYL A CRYLATE / SODIUM ACRYLOYLDIMET HYL TAURATE CO POLYMER / AQUA( WATER) / C15-23 AL KANE / DECYL GLU COSIDE / C13-14 AL KANE / GLYCERIN 1,00 FLOCCULOSINE SOLABIA PROPANEDIOL / GL YCOLIPIDS 2,00 ACIDE CITRIQUE S OLUTION 10% / AQUA (WATER) / CI TRIC ACID 0,18 TOTAL 100,00

[0106] Balm-type formulations are suitable for the care of facial and / or body skin. Balms have a richer structure than creams or milks. In particular, they allow targeted application of the active agents contained in the balm and are generally used to deeply nourish and moisturize the skin. Balms are of particular interest for areas of the body exposed to environmental aggressions (such as the face and hands). Thus, a balm containing flocculosine is particularly suitable for soothing the skin at the site of feelings of pulling, tingling or any other feeling of discomfort and / or to prevent said sensations. Example 4#: Preparation of flocculosin

[0107] The flocculosine used in the above-mentioned examples was produced according to the process comprising the following steps:

[0108] i-precultures of Pseudozyma flocculosa

[0109] A plant extract-based agar medium (BK205, BIOKAR diagnostics) is inoculated from a culture sample stored at -80°C.

[0110] The culture dishes are incubated in an incubator for 24 hours at 30°C.

[0111] Liquid medium cultures are then carried out so as to obtain an inoculum of sufficient volume to inoculate the main culture.

[0112] ii-culture in liquid medium

[0113] The main culture takes place in a bioreactor for 3 days, with stirring at 35 rpm at 25 degrees and in aerobic conditions.

[0114] iii-aerobic fermentation

[0115] The third step of the process consists of fermenting the culture so as to obtain a fermented culture. It is carried out aerobically and with stirring of the culture under the conditions specified previously.

[0116] iv-lysis of cells

[0117] When at least 85% of the carbon source of the culture medium is consumed. The culture is stopped and the cells lysed by applying a heat treatment at 100°C of the culture.

[0118] The lysate thus obtained comprises all the components derived from the fungus Pseudozyma flocculosa including flocculosin.

[0119] v-solid liquid separation

[0120] The lysate is subjected to a solid-liquid separation step so as to obtain the flocculosin solubilized in a solvent such as propanediol.

[0121] solid liquid separation

[0122] The solubilized flocculosin is filtered to remove unwanted components. This step is carried out using a filtration membrane having a pore size of at most 22 μm.

[0123] At the end of this last step, a composition is obtained comprising flocculosine at a concentration of between 0.02% and 0.08% by mass, i.e. between 0.2g / L and 0.8g / L, in a solvent with a minimum purity of 80%.

[0124] For the experiments of examples 1 to 3 the preparation of flocculosine was standardized to 0.5 g / L of flocculosine in propanediol. Bibliography

[0125] Cheng Y, McNally DJ, Labbé C, Voyer N, Belzile F, Bélanger RR. Insertional mutagenesis of a fungal biocontrol agent led to discovery of a rare cellobiose lipid with antifungal activity. Appl Environ Microbiol. 2003 May;69(5):2595-602.

[0126] Démarchez et al. Biology of the skin: https: / / biologiedelapeau.fr / ).

[0127] Gao F, Zhang LH, Su TF, Li L, Zhou R, Peng M, Wu CH, Yuan XC, Sun N, Meng XF, Tian B, Shi J, Pan HL, Li M. Signaling Mechanism of Cannabinoid Receptor-2 Activation-Induced [3-Endorphin Release. Mol Neurobiol. 2016 Aug;53(6):3616-3625.

[0128] Mimee B, Labbé C, Pelletier R, Bélanger RR. Antifungal activity of flocculosin, a novel glycolipid isolated from Pseudozyma flocculosa. Antimicrob Agents Chemother. 2005 Apr;49(4):1597-9.

[0129] Mimee B, Determination of the spectrum of activity and mode of action of flocculosin, an antimicrobial molecule isolated from Pseudozyma flocculosa. Doctoral thesis in plant biology, Université Laval, 2008. https: / / corpus.ulaval.ca / entities / publicatio n / 66aa8ec9-db70-4031-9c37-3c25445b23db.

[0130] Traquair JA, Shaw LA, Jarvis WR. New species of Stephanoascus with Sporothrix anamorphs.Can. J. Bot. 1988, 69, pp. 926-933.

[0131] Yang TT, Sinai P, Kain SR. An acid phosphatase assay for quantifying the growth of adhèrent and nonadherent cells. Anal Biochem. 1996 Oct 1 ;241( 1): 103-8.

Claims

Claims

1. A method of soothing cosmetic care for sensitive skin, characterized in that it comprises the application to said sensitive skin of a composition comprising flocculosine as active agent which stimulates the production of beta-endorphin and / or the expression of the CB2 receptor by the cells of said sensitive skin, said composition optionally comprising at least one cosmetically acceptable excipient.

2. A method according to claim 2, characterized in that flocculosin is included in the composition, at a concentration of between 0.5 parts per million and 25 parts per million, preferably between 1.00 parts per million and 15.00 parts per million by mass of said composition.

3. Method according to any one of claims 2 to 3, characterized in that the flocculosin is incorporated into the composition in dissolved form in a solvent selected from: propanediol, glycerin or butylene glycol.

4. A method according to any one of claims 2 to 4, characterized in that the composition comprises from 0.1% to 5% by mass of a preparation at 0.50 grams per liter of flocculosin.

5. A method according to claim 5, characterized in that the preparation at 0.50 grams per liter of flocculosine is propanediol comprising 0.50 grams per liter of flocculosine.

6. Method according to any one of claims 2 to 6, characterized in that the composition is in the form of a cream, a balm, a lotion, an oil, a butter or a spray.

7. Method according to any one of claims 2 to 7, characterized in that the flocculosine is combined with another cosmetically acceptable active substance, chosen from, designated according to their INCI name: maltodextrin (and) biosaccharide gum-1; biosaccharide gum-1; aminopropanediol esters linseed oil / palm oil; biosaccharide gum-4 (and) 1,2-hexanediol; propylene glycol / water / Theobroma cocoa extract; Butylene glycol (and) water (and) Ageratum conyzoides leaf extract; or propanediol (and) water (and) Vitis vinifera grape juice extract, or mixtures thereof.

8. Method according to any one of claims 2 to 7, characterized in that the soothing effect obtained by stimulation of the production of beta-endorphin by the skin cells comprises the prevention and / or reduction of at least one skin sensation selected from: tingling, prickling, sensations of tightness, sensations of heat or even burning sensations, itching and / or the appearance of skin redness in reaction to stimuli which, in an individual not having sensitive skin, have no effect on other skin types.

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