Pharmaceutical composition comprising a Pickering's oil-in-water emulsion containing an organomodified phyllosilicate, particularly for its use as an anti-inflammatory, healing, and anti-allergy agent.

Abstract

Pharmaceutical composition comprising a Pickering oil-in-water emulsion containing an aqueous phase, a vegetable oil phase, and an organomodified phyllosilicate, particularly for its use in increasing TAFA4 production, and possibly for increasing serotonin production, for its use as a cutaneous anti-inflammatory agent and / or wound-healing agent and / or as a cutaneous anti-allergy agent. Figure to be published with the abstract: none.

Description

Title of the invention: Pharmaceutical composition comprising a Pickering oil-in-water emulsion containing an organomodified phyllosilicate, particularly for its use as an anti-inflammatory, healing, and anti-allergy agent.

[0001] The present invention relates to the medical field and more particularly to a pharmaceutical composition comprising a particular Pickering oil / water emulsion, especially for its use as an anti-inflammatory and / or healing and / or anti-allergy agent.

[0002] The skin is the main protective barrier of the human body against external aggressions such as air pollution, climatic variations, UV radiation and also against potentially harmful antigens.

[0003] The skin consists of three layers: the epidermis, the dermis, and the hypodermis. The epidermis, which is in contact with the superficial layer, is particularly involved in interactions with the external environment. The epidermis is covered by a hydrolipidic film and is composed of four layers: the stratum corneum, the stratum granulosum, the stratum spinosum, and the stratum basale. The epidermis is normally composed of four types of cells: keratinocytes, which represent 80% of all its cells, with the remaining 20% ​​being composed of melanocytes, Langerhans cells (or immunocompetent cells), and Merkel cells, these three cell groups being dispersed among the keratinocytes.

[0004] When an antigen, or more generally a pathogen, crosses the skin barrier, an inflammatory response is triggered by the body's immune system.

[0005] This response results in the production of T cells, polymorphonuclear cells, and macrophages. Normally, this inflammatory response is controlled and ceases as soon as the pathogen is eliminated.

[0006] This response can also occur in the absence of a pathogen but in the presence of other factors likely to cause damage, such as UV rays. Indeed, UV rays can cause damage leading to epidermal injury and inflammation of the underlying dermal papilla.

[0007] The TAFA4 (or FAM19A) protein is a 12 kDa neurokine belonging to the TAFA family of proteins. This protein is involved in various cell cycle regulatory processes such as the modulation of the immune response: phagocytosis, release of reactive oxygen species (ROS) or chemotaxis of macrophages. TAFA4 is primarily expressed in nociceptors; it is a ligand for C-low-threshold mechanoreceptors (C-LTMRs). This neurokine is a specific marker of C-LTMRs and is involved in pain perception in the spinal cord.

[0008] TAFA proteins represent a new class of chemokine-like ligands that are revealed to be neuron-derived secretory proteins, or neurokines, and are notably involved in the regulation of immune responses within the central nervous system. As a secreted protein, TAFA4 binds to the formaldehyde peptide receptor 1 (FPR1), a G protein-coupled receptor, on the cell surface, and acts as a mediator of macrophage chemoattraction, phagocytosis, and the inflammatory profile of macrophages.

[0009] Publications (1) and (2) demonstrate the role of TAFA4 in the regulation of cutaneous inflammatory disorders and tissue regeneration, and patent application WO 2020 / 064907 discloses a method for reducing skin inflammation comprising administering to a subject an active amount of a TAFA4-type polypeptide or a nucleic acid molecule encoding TAFA4. Publication (4) demonstrates the role of TAFA4 in allergen-specific immunotherapy.

[0010] There remains a need for new pharmaceutical compositions capable of controlling and reducing skin inflammation, as well as skin allergies.

[0011] Furthermore, Merkel discs are superficial receptors located at the base of the epidermis and composed of the terminal of a disc-shaped branch of a myelinated fiber attached to a Merkel cell with which it establishes synaptic contacts. Areas rich in Merkel discs can form tactile domes that respond to localized pressure, the stimulus response being phasicotonic with slow adaptation.

[0012] Recently, research on Merkel cells has focused on their function in mechanosensation, in particular light touch, due to their primary role in sensory tasks and social interactions.

[0013] In particular, it has been shown that Merkel cells use serotonin to transmit tactile stimuli to the terminals of the AP-afferent nerves with which they are in contact and that tactile stimuli activate Piezo 2 channels to transduce mechanical stimuli into electrical stimuli leading to the generation of impulses on the AP-afferent nerves (3).

[0014] This research has highlighted the importance of serotonin in the neurotransmission of information from skin cells in the epidermis.

[0015] Serotonin is a neurotransmitter that is transmitted both to the nerve microfibril underlying the Merkel cell groups (at the level of the layer basal layer of the epidermis), than to the Langerhans cells in the epidermis. Langerhans cells are positively biostimulated by the mediator "serotonin". Langerhans cells are the first line of the immune system; by stimulating these cells, the immune system is strengthened.

[0016] Serotonin produced in Merkel cells has neurotransmitter properties and is capable of transmitting a positive message from the skin to the brain (example "sensation of caress") and of exerting a beneficial (neuro-protective) effect on the sensory neurons present in the skin.

[0017] Unexpectedly and advantageously, the inventor observed that a composition comprising a particular Pickering H / W emulsion makes it possible to increase both the secretion of serotonin and also the secretion of TAFA4. Summary of the invention

[0018] The inventor has implemented a new pharmaceutical composition comprising a particular Pickering emulsion exhibiting, in particular, anti-inflammatory, healing and / or anti-allergy properties.

[0019] According to a first aspect, the present invention relates to a pharmaceutical composition comprising a Pickering O / W emulsion containing an aqueous phase, a vegetable oil phase and an organomodified phyllosilicate.

[0020] According to a second aspect, the present invention aims at said pharmaceutical composition for its use in increasing the production of TAFA4.

[0021] According to a third aspect, the present invention aims at said pharmaceutical composition for its use in increasing serotonin production.

[0022] According to a fourth aspect, the present invention relates to said pharmaceutical composition for its use as a cutaneous anti-inflammatory agent and / or as a healing agent, and / or as a cutaneous anti-allergy agent.

[0023] According to a fifth aspect, the present invention relates to said pharmaceutical composition for use as a cutaneous anti-inflammatory agent for the prevention and / or treatment of an inflammatory skin disease, preferably selected from the group consisting of acne, rosacea, folliculitis, perioral dermatitis, photoaging, skin aging, psoriasis, ichthyosis, chronic wounds, pressure sores, keratosis pilaris, scars, including surgical and acne-related scars, sebaceous cysts, inflammatory dermatoses, post-inflammatory hyperpigmentation, xerosis, pruritus, lichen planus, prurigo nodularis, eczema, miliary fever, scleroderma, atopic dermatitis, nephrogenic fibrosing dermopathy, mixed connective tissue disease, scleromyxedema, the scleroedema, keloid, sclerodactyly, fasciitis eosinophilia, photodermatosis, venous stasis ulcers or diabetic foot ulcers, cutaneous fibrosis.

[0024] Another advantage of the composition according to the invention is that it gives a soothing effect to skin that has been under stress, more generally it has a eudermic action, that is to say it creates a feeling of well-being when applied to the skin.

[0025] The compositions according to the invention are also stable, non-irritating, non-toxic, and non-allergenic to the skin.

[0026] Other aspects, advantages, properties of the present invention are presented in the description and examples that follow. Detailed description

[0027] Definitions

[0028] In this text, unless otherwise specifically indicated, percentages are expressed as a percentage of a reference composition.

[0029] In the present text, intervals are defined abbreviatedly to avoid describing each and every value within the interval; however, any suitable value within the interval may be chosen as the upper, lower, or terminal values ​​of the interval. For example, an interval from 0.1 to 1.0 represents the terminal values ​​of 0.1 and 1.0, as well as the intermediate values ​​of 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and all intermediate intervals within 0.1 to 1.0, such as 0.2 to 0.5, 0.2 to 0.8, 0.7 to 1.0, and so on.Unless otherwise specified, an interval defined as "between value A and value B" includes both values ​​A and B and is therefore equivalent to an interval "from value A to value B". The expression "at least" includes the value stated after it, for example, "at least 5%" should be understood as also including "5%". The expression "a maximum of" includes the value stated after it, for example, "a maximum of 5%" should be understood as also including "5%".

[0030] Furthermore, in this text, measurable values, such as a quantity, shall be understood as including standard deviations that can be readily determined by a person skilled in the art in the relevant technical field. Preferably, these values ​​are intended to include variations of ± 5%.

[0031] By "skin" is meant the epidermis of the face or body or scalp.

[0032] Without wishing to be bound by any particular theory, it appears that the application to the skin of the composition comprising a specific Pickering emulsion allows the production of serotonin, also known as 5-hydroxytryptamine (5-HT), in the skin via the stimulation of Merkel cells. Serotonin is, in fact, a A neurotransmitter known to facilitate communication between neurons in the central nervous system. In response to this positive message, neurons release TAFA4: this mediator, which awaits maturation within the neurons, has its maturation activated by serotonin before being released. The release of TAFA4 leads to a reduction in skin inflammation and contributes to tissue regeneration and wound healing.

[0033] In addition, the pharmaceutical composition according to the invention, thanks to its particular galenic structure, provides the skin with a biomimetic effect of the comfort provided by a light caress or the action of blowing on a scratch; this effect can also be called the "caress effect".

[0034] This "caressing" effect is particularly pronounced when the composition is applied by spraying. The fine droplets remain on the skin's surface, thus mimicking corneocytes. The slight pressure exerted on the skin stimulates mechanoreceptors and releases neuropeptides that send signals to the brain similar to those of a light, pleasant caress. This signal is capable of suppressing any discomfort sent to the brain and replacing it with a message of well-being.

[0035] Pickling emulsions

[0036] Pickering emulsions are emulsions stabilized by solid particles. During the preparation of the emulsion, said solid particles position themselves at the interface between the aqueous phase and the oily phase.

[0037] The Pickering emulsions used according to the present invention are oil-in-water emulsions, i.e., H / W, stabilized by a particular clay which is a modified natural phyllosilicate.

[0038] Advantageously, the aqueous phase of the Pickering emulsion is present in an amount ranging from 43% to 93%, preferably 55% to 70% and preferably 58% to 65% by weight relative to the total weight of the composition.

[0039] According to a preferred embodiment, the modified natural phyllosilicate comprises a phyllosilicate selected from the group consisting of vermiculites and smectites. Preferably, the phyllosilicate may be selected from the group consisting of montmorillonites, bentonites, nonytronites, beidellites, volkonskoites, hectorites, saponites, sauconites, sobockites, stevensites, svinfordites; preferably, these are phyllosilicates of sodium, potassium, calcium, or mixtures thereof. More preferably, the phyllosilicate is selected from the group consisting of hectorite, montmorillonite, bentonite, or mixtures thereof.

[0040] According to a preferred embodiment, the modified natural phyllosilicate comprises an organic compound selected from the group consisting of xanthan gum, guar gum, tara or locust bean gum, acacia gum, carrageenan, alginate, chitosan, pectin, citric acid, tartaric acid, oxalic acid, succinic acid, malic acid, acetic acid, lactic acid, propionic acid, salicylic acid, glycosaminoglycans. Advantageously, the modified natural phyllosilicate comprises bentonite modified by xanthan gum and citric acid.

[0041] According to another embodiment, the modified natural phyllosilicate comprises an organic compound selected from any organic compound known in the art of Pickering emulsions, such as those disclosed in French patent no. FR 2 976 503.

[0042] Advantageously, the modified phyllosilicate is present in an amount ranging from 2% to 20%, preferably 2.5% to 10% and preferably 3.5% to 8% by weight relative to the total weight of the composition.

[0043] According to a preferred embodiment, the vegetable oil phase of the Pickering emulsion comprises at least one vegetable oil selected from the group consisting of sunflower oil, rapeseed oil, olive oil, camelina oil, peanut oil, coconut oil, grapeseed oil, castor oil, argan oil, Djansang oil, desert date oil, nigella oil, prickly pear oil, macadamia oil, soybean oil, palm and palm oil, Tamanu oil, sesame oil, linseed oil, walnut oil, hazelnut oil, baobab oil, passion fruit oil, Brazil nut oil, hibiscus oil, pumpkin seed oil, and oil of Luffa, Carapa oil, Evening Primrose oil, Borage oil, Avocado oil, Almond oil, Sea buckthorn oil, Apricot kernel oil, Cherry kernel oil, Apple seed oil, Pomegranate oil, Jojoba oil,Rosehip oil, plum oil, shea butter, cocoa butter, kokum butter, mango butter, moabi butter, karanja butter, tucuma butter, cupuaçu butter, buriti butter, murumuru butter, kombo butter, kpangnan butter, caprylic / capric acid triglycerides.

[0044] Advantageously the composition used in the present invention does not include hemp oil extract.

[0045] Advantageously, the oily phase of the Pickering emulsion is present in an amount ranging from 5% to 40%, preferably 10% to 30% and preferably 15% to 25% by weight relative to the total weight of the composition.

[0046] Composition

[0047] The pharmaceutical composition according to the invention is preferably a sprayable composition in fine droplets.

[0048] The pharmaceutical composition according to the invention may also be an oil-in-water cream or ointment type emulsion whose viscosity does not permit vaporization, but direct topical application. In this case, the microcapsules are dispersed on the surface of the skin by massaging with the fingertips.

[0049] Preferably, the composition usable according to the invention comprises from 43 to 93% by weight of water relative to the total weight of the composition.

[0050] Advantageously the composition according to the present invention comprises, in an acceptable medium, at least one additional agent selected from humectants, thickeners, texturizing agents, emulsifiers, dispersing agents, foaming agents, emulsifiers, preservatives, colorants, plant extracts, plant fibers, minerals, pH correcting agents, active ingredients and perfumes.

[0051] In particular, the pharmaceutical composition according to the invention advantageously comprises at least one amyrin. The amyrin is advantageously chosen from the group formed by α-amyrin (100% or viminalol), [3-amyrin (100%), a mixture of α- and [3-amyrins containing 20% ​​to 80% α-amyrin and 20% to 80% [3-amyrin, preferably a mixture of α- and [3-amyrins containing 20% ​​to 80% α-amyrin and 20% to 80% [3-amyrin.

[0052] Advantageously the composition according to the present invention comprises from 0.001 to 20% by weight of at least one additional agent relative to the total weight of the composition.

[0053] Of course, a person skilled in the art will take care to choose these additional agents so as not to alter the properties of the composition usable according to the invention, in particular so as not to alter the properties giving this composition its vaporizable character.

[0054] Advantageously, the process for preparing the composition according to the invention comprises at least the following steps in this order: prepare the aqueous phase; add the organomodified phyllosilicate to the aqueous phase and mix; add the vegetable oil phase to the mixture obtained and obtain a Pickering oil / water emulsion.

[0055] Uses

[0056] The pharmaceutical composition according to the invention is advantageously intended to be applied to the skin by spraying, vaporization.

[0057] The following examples are intended to illustrate the invention without limiting its scope. Examples

[0058] A-Compositions

[0059] Table 1 lists the products used to prepare composition A usable according to the invention.

[0060] [Tables 1] Phase Commercial name % INCI A Water Qsp Aqua A Frametime CXG marketed by Ephyla 2.50 Bentonite & xanthan gum & Sodiu m stearoyl glutamate & citric acid B Refined sunflower oil commercially Used by CAUVIN 8.00 Helianthus annuus seed oil C Georgard Ultra marketed by L onza 1.00 Gluconolactone & Sodium benzoat e & Calcium gluconate C Sodium benzoate m 0.30 Sodium benzoate Total 100

[0061] Preparation of composition A

[0062] The constituents of phase A were mixed at 20°C with a mechanical knife mixer or a rotor stator at a speed of 4000 rpm for 10 minutes so as to implement sufficient shear and dispersion to obtain homogenization of the phase.

[0063] Phase B was then incorporated, still at 20°C, on the same shearing pattern gradually over 10 minutes.

[0064] The Pickering emulsion was thus prepared. The temperature of the mixture, under shear, was then increased to reach 50°C in order to solubilize the preservative.

[0065] Phase C (preservatives) was then introduced at this temperature of 50°C under a more moderate stirring of 2000 rpm.

[0066] The product is cooled to room temperature.

[0067] Finally, the pH was adjusted to 4.9.

[0068] The formulation of composition A comprises fine oil droplets coated with bentonite platelets. These mineral platelets are stable at the oil / water interface; they result from the exfoliation of bentonite (Frametime CXG) under the action of mechanical shear and form oil microcapsules. The dispersion of the microcapsules is stable when the product is at rest, even if its viscosity is low.

[0069] The size of the microcapsules is on the order of 5 to 15.106 m in diameter, which allows this galenic to pass through standard type spray nozzles in cosmetics.

[0070] This composition A was sprayed onto the skin of an arm showing signs of inflammation following sun exposure. Ten hours after application, a marked reduction in the inflammatory state was noted: the sensation of heat and the visual signs of skin inflammation disappeared.

[0071] Table 2 lists the products used to prepare composition B usable according to the invention.

[0072] [Tables2] Phase Trade name % INCI A Water 73.70 Aqua B Georgard Ultra marketed by Lo nza 1.00 Gluconolactone & Sodium benzoate & Calcium gluconate B Sodiu m benzoate 0.30 Sodium benzoate C Frametime CX marketed by Ep hyla 4.50 Bentonite & xanthan gum & citric acid C Xanthan gum FF commercially Used by Jungbunz lauer 0.50 xanthan gum D Capric / caprylic acid triglyceride 20.00 Caprylic / capric triglyceride Total 100

[0073] Preparation of composition B:

[0074] Phases A and B were mixed to form an aqueous phase, then phase C was added and the mixture was blended. Finally, the oily phase D was added and the mixture was blended. Once the Pickering emulsion was obtained, the pH was adjusted to 5.00.

[0075] The galenic form of the resulting composition B comprises fine oil droplets coated with bentonite platelets. These mineral platelets are stable at the oil / water interface; they are produced by the exfoliation of bentonite (Frametime CXG) under the action of mechanical shear and form oil microcapsules. The dispersion The microcapsules are stable when the product is at rest; its viscosity corresponds to that of a cream that fits in a standard cream jar.

[0076] This composition B was manually applied to the scratched skin of a knee. The cream provided a lasting, soothing, and comforting effect, creating a feeling of well-being. Ten hours after application, the beginnings of healing were observed.

[0077] This type of "microencapsulated" formulation allows for the application or misting of a layer of microcapsules containing skin-care lipid molecules. As they dry, the microcapsules gradually release the lipid molecules, providing a moisturizing effect and long-lasting anti-inflammatory and healing substances, as well as improving skin hydration as more microcapsules are released.

[0078] Thus the galenic formulation helps to balance the skin surface by specifically addressing skin dryness in the driest areas and by not adding oily substances to oily areas.

[0079] B - Measurement of the increase in serotonin production and the increase in TAFA4 production

[0080] Tested compositions

[0081] Composition A is used as the composition according to the invention.

[0082] For comparison purposes, the following were used: physiological saline, i.e. a 0.9% NaCl composition, as a baseline control (BC) and of del-naphthyl isothiocyanate at a concentration of 0.25% (V / V) as a positive control (TP).

[0083] Principle of the study

[0084] For this study, normal fresh human skin expiants with Merkel cells are incubated for 20 hours at 32°C for acclimatization.

[0085] Then the explant samples to be tested -in triplicate- are treated by spraying with composition A used in accordance with the invention or by spraying with the control compositions TB and TP and placed back into incubation at 32°C.

[0086] After 3 hours, a first series of treated explant samples was recovered and the treated explants were dissected and prepared: placed in liquid nitrogen for 3 minutes, then in 10 mL of ice-cold PB S IX and then in an ultrasonic bath for 45 minutes to obtain a cell lysate.

[0087] After this treatment carried out for each implant, 2mL of cell lysate from each explant sample of this first series were taken and 1% of stabilizing agent was added to preserve them at -20°C until the ELISA assays were carried out.

[0088] The expiants treated for 3 hours using compositions A, TB and TP are respectively named A3, TB3 and TP3.

[0089] After 8 hours, a second set of treated explant samples was collected and treated as above. Then, 2 mL of cell lysate from each explant sample in this second set was taken, and 1% stabilizing agent was added to preserve them at -20°C until the ELISA assays were performed.

[0090] The expiants treated for 8 hours with compositions A, TB and TP are respectively named A8, TB8 and TP8.

[0091] At the time of carrying out the Elisa assays, the treated explant samples were subjected to a new ultrasonic bath for 35 minutes and then, after homogenization, the supernatants were recovered for carrying out the Elisa tests.

[0092] B1 Measurement of the increase in serotonin production

[0093] Merkel cells in the skin release neurotransmitters, particularly serotonin, to transmit information about a "caressing" touch to the brain via the underlying nerve fiber. This is how mechanoreceptors (Merkel cells or Merkel corpuscles) ensure our sense of touch, especially positive sensations; they translate a mechanical effect, namely a "caressing" touch, into a chemical message, namely serotonin, a neurotransmitter that the brain associates with well-being.

[0094] This study is based on the ability of the composition according to invention A to increase serotonin production.

[0095] The desired effect is a stimulating effect on the production of serotonin which results in a comforting effect, a feeling of well-being, a caressing effect on the epidermis which is in contact with the external environment.

[0096] ELISA test system - serotonin

[0097] The standard and control solutions were prepared in accordance with the instructions for the Elisa - serotonin kit (commercial reference of the kit: Serotonin Research ELISA ® marketed by Immusmol).

[0098] The kit provides a practical test for the determination of the serotonin concentration of media comprising prepared skin explant supernatants, thus allowing the modulatory effect of the topical composition to be tested to be evaluated.

[0099] This kit implements an ultrasensitive enzymatic immunoassay method for the quantitative determination of serotonin. Serotonin is acylated and then detected by antigens bound to the solid phase of the microtiter plate. Standards, controls, and acylated samples, along with analytes bound to the solid phase, compete for a fixed number of antibody-binding sites. Once the system reaches equilibrium, free antigen and free antigen-antibody complexes are eliminated. by washing. The antibody bound to the solid phase is detected by an anti-rabbit IgG-peroxidase conjugate using TMB ((3,3',5,5'-Tetramethylbenzidine)) as a substrate. This is therefore a colorimetric test, the color reaction of which is revealed at 450 nm. Quantification of unknown samples is obtained by comparing their absorbance with a standard curve prepared with known standard concentrations.

[0100] Results

[0101] Standard range

[0102] For this study, a serotonin calibration range from 0.0 to 2.5 × 10⁹ g / mL (ng / mL) was established. The absorbances of the serotonin calibration range (optical density (OD)) at 450 nm are presented in Table 3.

[0103] [Tables3] DO450nm White SO Standards = Serotonin Range (109 g / mL) SI = 0.00 0 S2 = 0.015 S3 = 0.05 0 S4 = 0.150 S5 = 0.2 50 Replicat 1 12.545 11.633 11.095 9.839 6.903 4.309 Replicat 2 12.555 11.698 10.982 9.679 7.263 3.895 Replicat 3 13.053 12.929 9.643 9.074 6.760 4.182 Average 12.718 12.087 10.573 9.531 6.975 4.129 Standard deviation 0.290 0.730 0.807 0.403 0.259 0.212

[0104] The equation of the calibration curve is: y = 28.673x² - 25.137x + 12.393 The coefficient of determination is: R² = 0.9719

[0105] Measurement of samples

[0106] The absorbance (OD) results at 450 nm with standard deviations of conforming composition A and of the TB and TP controls at 3 hours and 8 hours are presented respectively in Table 4 below. The percentage (%) increase compared to the corresponding baseline control is shown.

[0107] [Tables4] OD 450 nm of composition A and controls and standard deviation TB3 TP3 A3 TB8 TP8 A8 OD 450 nm 0.204 0.340 0.246 0.203 0.254 0.246 Standard deviation 0.020 0.031 0.028 0.026 0.060 0.025 % increase compared to baseline control 0 66.67 20.58 0 25.12 21.18

[0108] Under the study conditions, the kinetics of the positive response with respect to the time of contact with the skin expiants show that the expected peak stimulation with the positive control (del-naphthyl isothiocyanate) is observed after 3 hours of contact, with 66.67% more serotonin produced compared to the skin expiant control without the test product. This positive response to the positive control validates the experiment. After 8 hours of contact, the positive effect of the positive control decreases very significantly; the effect is decreasing between 3 and 8 hours of contact.

[0109] With composition A according to the invention, the increase in serotonin production, compared to the baseline control TB3, is 20.58% after 3 hours (A3), and remains the same after 8 hours (21.18% after 8 hours). The positive effect of composition A according to the invention is therefore stable over time, which demonstrates the persistence of this positive effect.

[0110] Conclusion:

[0111] The composition according to the invention A applied to the exposed expiants stimulates the production of serotonin by more than 20% compared to the baseline control after 3 hours of contact with the expiant, this production is maintained at +21% compared to the baseline control after 8 hours of contact (A8).

[0112] It is recalled that in the skin, Merkel cells are the mechanoreceptors on the front line of the sense of touch, as well as the main cells capable of producing serotonin in significant quantities. Serotonin is a neurotransmitter of the sensation of caressing which, via the nerve fibril underlying the Merkel cells, informs the brain that a pleasant and positive sensation.

[0113] Thus, the composition according to the invention A, by increasing the production of the neuro-mediator serotonin, informs the brain of a positive modulation of the caress type or positive sensory effect.

[0114] B2 -Measurement of the increase in TAFA4 production

[0115] TAFA proteins are neuron-derived secretory proteins, or neurokines, and are notably involved in the regulation of immune responses within the central nervous system. As a secreted protein, TAFA4 binds to the formalin peptide receptor on the cell surface and acts as a mediator of macrophage chemoattraction, phagocytosis, and the inflammatory profile of macrophages.

[0116] This study is based on the ability of the composition according to invention A to increase the production of TAFA4.

[0117] The desired effect is a stimulatory effect on the production of TAFA4 which results in an anti-inflammatory and pro-healing effect.

[0118] For this study, the TAFA-4 (Human Chemokine-Like Protein TAFA-4) ELISA kit provides a practical test for the quantification of TAFA-4 and the evaluation of the biostimulation of wound healing by this protein.

[0119] This kit uses monoclonal antibodies specific to TAFA-4. The interaction between TAFA-4 and the antibodies is detected by adding a substrate that leads to color production. The color intensity is measured spectrophotometrically at 450 nm and is proportional to the concentration of TAFA-4. A calibration curve is used to determine the concentration of TAFA-4 in the samples.

[0120] The standard and control solutions were prepared in accordance with the instructions for the Elisa kit - T AF A4 (commercial reference of the kit: Human chemokine-Like Protein TAFA-4 marketed by Abbexa).

[0121] The kit provides a practical test for the determination of the concentration of TAFA4 in media comprising prepared skin explant supernatants, thus allowing the modulatory effect of the topical composition to be tested to be evaluated.

[0122] This kit is based on the sandwich enzyme immunoassay technology. An antibody is pre-coated onto a 96-well plate. Standards, test samples, and a biotin conjugate reagent are added to the wells and incubated. The HRP (Horseradish Peroxidase) conjugate reagent is then added, and the entire plate is incubated. Unbound conjugates are removed using a wash buffer at each step. The TMB substrate (3,3',5,5'-tetramethylbenzidine, or TMB, is a chromogenic substrate used in immunohistochemistry and as a peroxidase indicator in the ELISA technique) is used to quantify the HRP enzymatic reaction. Once the TMB substrate is added, only the wells containing sufficient TAFA4 will produce a blue product, which then turns yellow after the addition of the acidic stop solution. The intensity of the yellow color is proportional to the amount of TAFA4 bound on the plate.Optical density (OD) is measured by spectrophotometry at 450 nm in a microplate reader, from which the concentration of TAFA4 can be calculated.

[0123] Results

[0124] Standard range

[0125] For this study, a TAFA4 calibration range from 0.0 to 10.00 10⁹ g / mL (ng / mL) was established. The results: OD 450 nm (optical density at 450 nm) and calibration curve are presented in Table 5.

[0126] [Tables5] OD450nm White S0 Standards =TAFA4 range (109 g / mL) SI =0.16 S2 = 0.31 S3 = 0.63 S4 = 1.25 S5 = 2.50 S6 = 5.00 S7 = 10.00 Repl. 1 0.156 0.251 0.314 0.471 0.791 1.561 2.709 4.176 Repl.2 0.210 0.260 0.304 0.456 0.841 1.522 2.546 4.225 Repl. 3 0.227 0.230 0.307 0.422 0.872 1.462 2.500 4.094 Mean 0.198 0.247 0.308 0.450 0.835 1.515 2.585 4.165 Standard deviation 0.037 0.015 0.005 0.025 0.041 0.050 0.110 0.066

[0127] The equation of the calibration curve is: y = 0.4193x the coefficient of determination is: R2 = 0.9906

[0128] Test system:

[0129] For this study, full-thickness fresh human skin discs are exposed to physiological saline before the start of the contact period. The skin discs are then incubated for 15 to 20 hours at 32 ± 1 °C for acclimatization. At the end of the acclimatization period, samples for testing, either a basal control (physiological saline) or a positive control (supplied by EPHYLA), are sprayed onto the skin discs before an 8-hour incubation at 32 ± 1 °C. After the incubation time, the skin discs are processed to produce tissue homogenates using PBS IX. All samples are stored at -80 °C until the TAFA4 test.

[0130] Measurement of samples

[0131] The absorbance (OD) results at 450 nm with standard deviations of conformal composition A and controls TB and TP at 8 hours are presented respectively in Table 6 below. The (multiplicative) increase factor relative to the corresponding baseline control

[0132] [Tableauxô] OD 450 nm of composition A and controls and standard deviation TB3' A3' TB8' A8' OD 450 nm 0.025 0.249 0.001 0.198 Standard deviation 0.003 0.026 0.002 0.021 Multiplicative factor of increase compared to baseline: 0 9.96 0 198

[0133] Under the study conditions, the baseline level is always very low (TB3' and TB8'). When composition A according to the invention is applied, the rate of increase in TAFA4 secretion increases as early as 3 hours after skin contact (A3'), and this rate remains very high 8 hours after skin contact (A8'). This positive response validates the experiment and shows that, in response to the positive message generated by serotonin, the neuron releases TAFA4: this mediator, which is awaiting maturation in the neuron, has its maturation activated under the action of serotonin before being released after a period of between 3 and 8 hours.

[0134] The experiment was repeated for confirmation. The absorbance (OD) results at 450 nm with standard deviations of conformal composition A and baseline control TB at 8 hours are presented in Table 7 below, along with the percentage (%) increase compared to the baseline control.

[0135] [Tables?] 450 nm DO of composition A and controls and standard deviation TB8” A8” DO 450 nm 0.143 0.312 Standard deviation 0.008 0.018 % increase compared to baseline control 0 118.2

[0136] Conclusion:

[0137] The baseline TAFA4 level is significant with a very low standard deviation (this level is therefore robust and representative). When composition A according to the invention is applied, the TAFA4 secretion level increases significantly 8 hours after contact (A8” above); this result is based on a very low standard deviation, and is therefore robust and representative.

[0138] Composition A according to the invention thus increases the amount of TAFA4 in the skin by more than 118%. This increase results from the secretion of TAFA4 by nerve microfibrils. Like a caress on the skin, composition A according to the invention stimulates mechanoreceptors, particularly those that enable the production of serotonin-type neurotransmitters. The sensory nerve fibers are positively stimulated and secrete TAFA4 as a reward. This which What is surprising is that the nerve fibers are cut in an expiant, nevertheless their endings contain the metabolism allowing the secretion of TAFA4, a molecule induced in its production by the brain.

[0139] Thus, the composition according to the invention A, by increasing the production of TAFA4, leads to a reduction in skin inflammation and contributes to tissue regeneration and healing.

[0140] BIBLIOGRAPHY 1. Molecular Structure, Expression and Rôle of TAFA4 and its Receptor FPR1 in the Spinal Cord. Zhu S, Hu X, Bennett S, Mai Y and Xu J. Front iers in Cell and Dev elopmental Biol ogy (2022) 10:911414.doi: 10.3389 / fcell.2022.911414 B 2. Sensory neuron-derived TAFA4 promotes macrophage tissue repair functions Guillaume Hoeffel, Guilhaume Debroas , Anais Roger, Rafaëlle Rossignol, Jordi Gouilly , et al , Nature 2021, 594 (7861), pp.94-99 10.1038 / s41586-021-03563-7 hal-03419356 3. Effects on tactile transmission by serotonin transporter inhibitors at Merkel dis es ofmouse whisker hair follicles, Chang and G Gu, Molecular Pain vol. 16 : 1-9, 20 may 2020 4. TAFA4-IL-10 axis potentiate immunotherapy for airway allergy by induction of spécifie regulatory T cells , Qiu et al. npj Vaccines (2022) 7:133 ;.

Claims

Demands

1. Pharmaceutical composition comprising a Pickering O / W emulsion containing an aqueous phase, a vegetable oil phase and an organomodified phyllosilicate.

2. Pharmaceutical composition according to claim 1 in which organomodified phyllosilicate is present in an amount from 2% to 20%, preferably 2.5% to 10% and preferably 3.5% to 8% by weight relative to the total weight of the composition.

3. Pharmaceutical composition according to any one of claims 1 or 2 wherein the aqueous phase of Pickering's emulsion is present in an amount from 43% to 93%, preferably 55% to 70% and preferably 58% to 65% by weight relative to the total weight of the composition.

4. A pharmaceutical composition according to any one of claims 1 to 3, wherein the vegetable oil phase of the Pickering emulsion comprises at least one vegetable oil selected from the group consisting of sunflower oil, rapeseed oil, olive oil, camelina oil, peanut oil, coconut oil, grapeseed oil, castor oil, argan oil, Djansang oil, desert date oil, black cumin oil, prickly pear oil, macadamia oil, soybean oil, palm and palm oil, Tamanu oil, sesame oil, linseed oil, walnut oil, hazelnut oil, baobab oil, passion fruit oil, Brazil nut oil, hibiscus oil, oil of pumpkin seed oil, luffa oil, carapa oil, evening primrose oil, borage oil, avocado oil, almond oil, sea buckthorn oil, apricot kernel oil, cherry kernel oilApple seed oil, pomegranate oil, jojoba oil, rosehip oil, plum oil, shea butter, cocoa butter, kokum butter, mango butter, moabi butter, karanja butter, tucuma butter, cupuaçu butter, buriti butter, murumuru butter, kombo butter, kpangnan butter, caprylic / capric acid triglycerides.

5. A pharmaceutical composition according to any one of claims 1 to 4, wherein the oily phase of Pickering's emulsion is present in an amount from 5% to 40%, of

6.

7.

8.

9.

10.

11.

12.

13. preferably 10% to 30% and preferably 15% to 25% by weight relative to the total weight of the composition. Pharmaceutical composition according to any one of claims 1 to 5 comprising, in an acceptable medium, at least one additional agent selected from humectants, thickeners, texturizing agents, emulsifiers, dispersing agents, foaming agents, emolients, preservatives, colorants, plant extracts, plant fibers, minerals, pH correctors, active ingredients and perfumes. Pharmaceutical composition according to any one of claims 1 to 6 wherein the composition is applied by spraying. Pharmaceutical composition according to any one of claims 1 to 7 for its use in increasing the production of T AF A4. A pharmaceutical composition according to claim 8 for its use in increasing serotonin production. A pharmaceutical composition according to any one of claims 1 to 9 for its use as a cutaneous anti-inflammatory agent. Pharmaceutical composition according to any one of claims 1 to 9 for use as a wound-healing agent. Pharmaceutical composition according to any one of claims 1 to 9 for use as a skin allergy relief agent. Pharmaceutical composition according to claim 10 for use in the prevention and / or treatment of an inflammatory skin disease, preferably selected from the group consisting of acne, rosacea, folliculitis, perioral dermatitis, photoaging, skin aging, psoriasis, ichthyosis, chronic wounds, bedsores, keratosis pilaris, scars, including surgical and acne-related scars, sebaceous cysts, inflammatory dermatoses, post-inflammatory hyperpigmentation, xerosis, pruritus, lichen planus, prurigo nodularis, eczema, miliary fever, scleroderma, atopic dermatitis, nephrogenic fibrosing dermopathy, mixed connective tissue disease, scleromyxedema, scleroedema, keloid, sclerodactyly, eosinophilic fasciitis, photodermatosis, venous stasis ulcers or diabetic foot ulcers, cutaneous fibrosis.