EP3829722A1

EP3829722A1 - Cosmetic or dermatological compositions

Info

Publication number: EP3829722A1
Application number: EP19742797.4A
Authority: EP
Inventors: François CANAC; Philippe RÉVELEAU; Jean Julien BARONNET
Original assignee: BCR
Current assignee: BCR
Priority date: 2018-07-30
Filing date: 2019-07-30
Publication date: 2021-06-09
Also published as: FR3084261A1; FR3084261B1; US20210315800A1; WO2020025584A1; KR20210116413A

Abstract

The invention relates to an alkaline hydrolysate of oyster meat, and to the cosmetic and dermatological uses thereof for treating signs of ageing such as wrinkles or blemishes or for improving the firmness of the skin and achieving a skin-firming effect.

Description

COSMETIC OR DERMATOLOGICAL COMPOSITIONS

The present invention relates to a new oyster extract, in particular oyster flesh and the pharmaceutical and cosmetic compositions containing it, more particularly those intended for topical application, their preparation process and their uses in dermatology or cosmetology, in particular in the treatment of skin disorders such as changes in skin texture, skin color, transparency of the skin, irritation and the appearance of wrinkles.

Skin aging results from two separate and independent processes which involve intrinsic or extrinsic factors. Extrinsic aging corresponds to aging caused by various and varied environmental factors and more particularly corresponds to photoaging due to exposure to the sun but also to pollutants, tobacco, etc. It results in alterations such as more or less thick wrinkles, the appearance of spots as well as the formation of "parchment" skin.

Intrinsic or chrono-biological aging corresponds to normal or physiological aging related to age and results in particular in a slowing down of the renewal of the cells of the epidermis and the appearance of fine wrinkles or fine lines. Thus with age, the skin loses part of the water retained in the extracellular matrix, then undergoes an aging process which leads to an increase in fibrosis and a decrease in the elasticity of the fibers. During the aging process, there is a change in the structure and skin functions.

The main clinical signs of skin aging are the appearance of fine lines and deep wrinkles, which obviously increase with age. The furrows and wrinkles are marked; the skin becomes hollow and loses its firmness; on the surface, the skin loses its luminosity.

Among the extrinsic factors, as indicated, there may be mentioned exposure to variations in temperature and humidity or exposure to pollutants, to UV, etc. Among the intrinsic factors affecting the radiance of the skin tone, we can cite stress, fatigue, hormonal changes, dehydration of the epidermis or an alteration of the barrier function of the skin, that is to say all the factors associated with chronobiological aging.

These extrinsic and intrinsic factors tend to cloud the complexion, to make it inhomogeneous, dull, waxy, to promote or even aggravate the presence of imperfections. skin, wrinkles, fine lines, age spots, age spots. These alterations in complexion, often of multifactorial origin, are an increasingly frequent cause of consultations in a beauty treatment center or with dermatologists.

In recent years, various hydrolysates obtained by enzymatic hydrolysis of plant and animal proteins with various proteolytic enzymes have been studied for their physiological activities, and they have been used for various processed foods, seasonings, shampoos, cosmetics, etc.

For example, KR101841088 describes an oyster extract obtained by proteolysis of oyster flesh via added proteases, at acidic pH. Said extract enriched in peptides derived from enzymatic proteolysis by exogenous proteases is used for the treatment of wrinkles.

The Applicant has surprisingly demonstrated that an oyster flesh extract, obtained by alkaline hydrolysis, therefore without enzymatic proteolysis or the addition of exogenous proteases, exhibited very interesting properties for the treatment of signs of skin aging and for stimulating skin cell growth.

The compositions according to the invention can be used in topical preparations, in the field of dermatology or cosmetology, with the aim of preventing or treating the signs of aging for which it will be necessary to reduce wrinkles, to fight against skin aging photoinduced or not, to revive the epidermal and dermal cellular activity, and thus to firm the skin, to increase its elasticity, to prevent or treat the tasks, even to stimulate the cicatrization.

Thus, the present invention relates, according to one embodiment, an oyster extract obtained by alkaline hydrolysis of oyster flesh.

By the term "oyster" is meant here a reference to a bivalve mollusc of the family Ostreidae.

More particularly, reference is made to the species Pynodonta, Crassostrea or Ostrea.

The genus of Pycnodonta gathers the species of bottom oysters, they live in places never discovering (up to 2000m). They have a very round shell made of vacuoles. The Crassostrea are oysters from the foreshore (part of the coastline discovering at each tide). Reproduction takes place outside the shell, at random encounters between ova and spermatozoa.

The genus Ostrea lives in areas always submerged or discovering only occasionally and has a different mode of reproduction: fertilization takes place inside the shell, then the larvae are rejected towards the outside world.

An oyster consists of two valves, or shells, enclosing a fleshy part. This fleshy part includes, the mantle, the gills, the milt according to the season and the adductor muscle.

In the context of the present invention, reference is made to an extract of "oyster flesh", it is an extract obtained from the fleshy part, that is to say, the whole comprising the mantle and the gills, the milt if necessary, and all or part of the adductor muscle.

Preferably, the oyster flesh used comprises the milt of the oyster.

The extract according to the invention is an extract obtained by alkaline hydrolysis of the oyster flesh.

Oyster flesh can be fresh or frozen, whole, cut or ground and then subjected to an alkaline hydrolysis step.

By the expression “alkaline hydrolysis” of the oyster flesh, it is meant here that the oyster flesh is incubated with an alkaline compound, at a pH between 8 and 13, particularly between 9 and 12. In particular, this hydrolysis is carried out without adding any external enzyme, particularly without adding any external proteolytic enzyme.

The alkaline hydrolysis according to the invention is not an enzymatic proteolysis taking into account the absence of addition of protease and the pH at which this hydrolysis is carried out.

The alkaline compound can be any base, in particular a strong base, such as NaOH or KOH, or also (Ca (OH) ₂ ) or NH ₄ OH, in quantity and at a concentration allowing the desired pH to be obtained.

According to a preferred embodiment, the extract according to the invention can be obtained by a method according to the invention described below. Such a process for preparing an extract according to the invention comprises a step of maceration of oyster flesh, in particular flesh with milt, in an alkaline medium at a pH between 8 and 13, particularly between 9 and 12, more particularly still around 11.

In particular, the oyster flesh, raw fresh or frozen, possibly reduced to pieces and / or ground, is mixed with a base, preferably a base, in particular a strong base and the whole is left to incubate, preferably at room temperature, for 2 to 12 hours, in particular for 3 to 9 hours, more particularly about 6 hours.

The oyster flesh is previously drained in order to remove excess water and / or mucus, and to avoid dilution of the alkaline hydrolysis medium. By drained oyster meat, is meant here oyster meat containing between 80 and 90%, by weight, of water, that is to say the native oyster meat but stripped of its water of vegetation or mucus.

The incubation mixture can be agitated by any suitable means, either continuously or intermittently.

The base chosen can be NaOH, KOH, (Ca (OH) ₂ ) or NH ₄ OH, in an amount and at a concentration sufficient to reach the desired pH.

Typically, the base, such as NaOH, NH ₄ OH, (Ca (OH) ₂ ) or KOH, for example, will have a concentration of 0.5 to 2 M, particularly 1 M.

According to another particular embodiment of the invention, the alkaline hydrolysis is carried out with stirring or statically, at a temperature between 2 ° C and 37 ° C, in particular between 2 ° C and 25 ° C, more particularly between 2 ° C and 20 ° C, more particularly still between 2 ° C and 15 ° C, or even between 2 ° C and 10C.

It can be assisted by ultrasound or by extrusion.

The duration of the hydrolysis can be between 1 minute and 48 hours, more particularly still approximately 3 to 10 hours, and more particularly approximately 6 hours. The extraction can be repeated once, or even 2 to 3 times.

The basic volume / mass ratio of oyster flesh can vary from 15: 1 to 2: 1, particularly from 15: 1 to 5: 1, more particularly of the order of 10: 1.

This ratio will vary depending on the concentration of the base and the amount of residual water contained in the oyster flesh. The ratio is not critical in itself and will be determined according to these parameters in order to obtain a pH of the mixture to be incubated in the range between 8 and 13, particularly between 9 and 12, more particularly around 11.

The invention thus relates to an oyster extract obtained by alkaline hydrolysis of oyster flesh at a pH between 8 and 13, particularly between 9 and 12 and without the addition of any external enzyme, particularly without the addition of external proteolytic enzyme .

The extract according to the invention is an extract of oyster flesh free of its mucus and / or its vegetable water.

After the stage of incubation in an alkaline medium as indicated above, the mixture is neutralized by adding an acid in order to obtain a pH of the medium of the order of 4 to 7, particularly from 4 to 6, more particularly from 4 to 5 The neutralization can be carried out by any suitable acid, weak or strong, for example chosen from citric acid, sulfuric acid, acetic acid or any other suitable acid.

The mixture neutralized or then subjected to a liquid / solid separation step in order to recover the limpid liquid phase free of particles in suspension.

Any suitable technique such as filtration, centrifugation to remove pieces, particles and cellular debris is suitable. Typically, the liquid / solid separation step is carried out in order to remove particles larger than 20 μm.

According to another particular embodiment of the invention, the solid phase is then separated by centrifugation or filtration in order to recover a clear liquid phase free of particles. Filtration can be carried out on filter paper or filtration plate having a cutoff threshold of between 5 and 20 μm, particularly between 10 and 20 μm. Suitable filters or filtration plates can be chosen from the range of K series depth filtration plates from Pall®. Such plates are composed of a balanced mixture of cellulose fibers, diatomaceous earth, and perlite, which allows the creation of a well-defined matrix. We can thus choose Pall® K series plates of type K300 to K900 for example. The liquid phase representing the extract can be more or less concentrated, up to the obtaining of a dry extract.

The clear liquid phase obtained constitutes an extract according to the invention. The dry matter of an extract according to the invention thus obtained can be between 2 and 15%, particularly between 2 and 12%, particularly around 10%, in% by mass. This dry matter of the extract includes the organic matter of the hydrolyzed oyster but also the added compounds, base for hydrolysis and acid for neutralization.

In another embodiment of the invention, a support can also be added during the concentration step so as to obtain an extract containing 1 to 75% of dry extract or dry matter.

The support can be maltodextrin, lactose, silica, glycerin, a glycol, or any other cosmetologically acceptable support and solubilizing the extract, preferably of biobased origin such as for example biobased glycols (1, 2- pentanediol; 1, 3-butanediol; 1, 3-propanediol ...), and also hydrotropes such as for example alkyl glycosides (Sepiclear, Apyclean, APXC4 ...).

According to a particular embodiment of the invention, the extract can be discolored, for example on activated carbon.

The extract thus obtained can be used as it is or more or less concentrated, or even dried in the form of powder with or without drying support.

The extract, without support, can thus be concentrated under vacuum to a mass content of dry matter of between 5 and 30%, preferably between 5 and 20% and more particularly still between 5 and 15%, or even more particularly around 10%.

Concentration can be carried out thermally (at a temperature preferably below 50 ° C. and under vacuum) in order to increase the Brix degrees and stabilize with respect to microbiological contamination.

The extract can also be dried alone or on a support (for example maltodextrin, starch or lactose for example).

Advantageously, the concentrated extract corresponds to an extract corresponding to 1.5 to 8 grams of extract for 1 gram of oyster flesh, more particularly between 2 and 6 grams of extract for 1 gram of oyster flesh , more particularly still about 3 to 5 grams of extract for 1 gram of oyster flesh, more particularly about 4 grams of extract for 1 gram of oyster flesh. This is drained oyster meat. The method of manufacturing the extract is characterized in that no exogenous enzyme is added to the mixture. In particular, no protease is added to the oyster flesh and base mixture.

The hydrolysis of the organic matter of the oyster therefore consists of alkaline hydrolysis and the organic matter is thus reduced to its essentially soluble organic and mineral components. In this alkaline hydrolysis, the combination of the movement of water, its temperature, and its alkalinity accelerates the process of dissolution and decomposition of tissues, which after a few hours of treatment, disappear giving a colored liquid rich in amino acids, peptides, carbohydrates, fatty acid soaps, nucleotides, salts, etc.

According to a particular embodiment, the oyster extract according to the invention comprising in% by weight, relative to the dry matter of the extract, from 1% to 10% of free amino acids; from 3% to 12% of proteins or peptides, from 0.005% to 0.05% of total sugars and from 0.1% to 1% of polyphenols.

The amount of free amino acid, in% by weight, relative to the dry matter of the extract, may be between 1 and 8%; that of proteins or peptides, in% by weight, relative to the dry matter of the extract, between 5 and 10%; that of total sugars, in% by weight, relative to the dry matter of the extract, between 0.01 and 0.05% and that of polyphenols, in% by weight, relative to the dry matter of the extract, between 0.1 and 0.5%. The% are expressed in% by weight relative to the dry matter of the extract. As indicated above, the material of the extract includes the organic material of the oyster but also more or less of compounds added for hydrolysis (i.e. base) and for neutralization (i.e. acid).

It is also an object of the present invention to provide a dermatological or cosmetic composition comprising an oyster extract according to the present invention and a dermatologically or cosmetically acceptable excipient.

The pharmaceutical or cosmetic composition according to the invention comprises an extract according to the invention as defined above in admixture with at least one pharmaceutically or cosmetically acceptable excipient. It is preferably a topical composition in the skin, in particular in the face skin and / or the skin of the hands.

In the present invention, the term “pharmaceutically or cosmetically acceptable” is intended to denote that which is useful in the preparation of a pharmaceutical or cosmetic composition, which is generally safe, non-toxic and neither biologically nor otherwise undesirable and which is acceptable for a pharmaceutical or cosmetic use, and in particular dermatological or cosmetic use, in particular by topical application. The compositions according to the invention are advantageously intended for topical application, in particular on the skin. Preferably, the cosmetically acceptable excipients are suitable for topical administration. Acceptable excipients allow in particular to ensure good stability, a pleasant texture and feel. It can also be, for example, agents for formulations or additives of known and conventional use in cosmetics: mention may be made of surfactants, colorants, preservatives, perfumes, film-forming agents, thickeners, etc.

The compositions according to the invention may thus be presented in the forms which are usually known for topical administration, that is to say in particular lotions, foams, gels, dispersions, emulsions, sprays, serums, masks or creams, with excipients allowing in particular skin penetration to improve the properties and accessibility of the active ingredient.

Advantageously, it will be a cream. These compositions generally contain, in addition to the extract according to the present invention, a physiologically acceptable medium, generally based on water or on a solvent, for example alcohols, ethers or glycols. They may also contain surfactants, complexing agents, preservatives, stabilizers, emulsifiers, thickeners, gelling agents, humectants, emollients, trace elements, essential oils, perfumes, dyes, matting agents, chemical or mineral filters, moisturizing agents.

According to one embodiment, the dermatological or cosmetic composition according to the invention is characterized in that the amount of oyster extract according to the invention is between 0.01% and 10% by weight relative to the total weight of the composition, more particularly between 0.05% and 5% by weight relative to the total weight of the composition. This percentage may vary depending on the dry matter content of the extract and its concentration.

Typically, the dermatological or cosmetic composition according to the invention is characterized in that it is presented in an oral or topical form, preferably in topical form.

The object of the present invention relates to the cosmetic, particularly non-therapeutic, use of an extract according to the invention or of a dermatological or cosmetic composition containing said extract according to the present invention or of this dermatological or cosmetic composition according to the invention to combat the signs of skin aging.

The cosmetic use of the extract according to the present invention or the cosmetic or dermatological composition according to the invention is more particularly intended to restore material to the skin, strengthen its firmness and visibly reduce marked wrinkles and deep furrows.

The present invention also relates to a method for combating the signs of skin aging comprising the administration, preferably topically, of an effective amount of an extract according to the invention or of a cosmetic or dermatological composition according to the invention to a person in need.

Another object of the present invention relates to a dermatological composition intended to accelerate skin repair in order to restore the integrity and the quality of the skin comprising, as dermatological or cosmetic active ingredient, the extract according to the invention and further comprising at minus a dermatologically or cosmetically acceptable excipient.

According to one embodiment, the present invention thus relates to the use of a cosmetic composition for the prevention and / or treatment of skin disorders, said cosmetic composition comprising, as active principle, an oyster extract according to the present invention.

In one embodiment, the use according to the invention is characterized in that the skin disorders are manifested by changes in texture, color, transparency of the skin, irritation and the appearance of wrinkles. More particularly, skin disorders are the result of environmental stress.

According to a particular embodiment, environmental stress is caused by the sun, tobacco.

According to an alternative, the use according to the invention is characterized in that the composition is in an oral or topical form, preferably in topical form.

Preferably, the topical form is chosen from the group comprising creams, gels, ointments and sprays.

In one embodiment where the use is for an oral form, it is characterized in that this oral form is chosen from the group comprising tablets, capsules and powders for oral suspensions. The composition according to the present invention can be administered orally or any other pharmaceutical administration route. The compositions according to the present invention can be formulated for administration to mammals, including humans. These compositions are produced so that they can be administered orally, sublingually, subcutaneously, intramuscularly, intravenously, transdermally. In this case, the active ingredient (s) can be administered in unit administration forms, in admixture with conventional pharmaceutical carriers, to animals or humans.

In the case of a food supplement or a drug, the following dosage forms can be considered: capsules, swallowing tablets, chewable tablets, effervescent tablets, lozenges, pills, powders, granules, oral solutions or suspensions and the forms sublingual and oral administration. The preferred dosage form is the capsule. When a solid composition is prepared in the form of a tablet, the extract according to the invention is mixed with a pharmaceutical vehicle such as gelatin, starch, lactose, magnesium stearate, talc, gum arabic, silica or the like. A preparation in capsules is obtained by mixing the extract according to the invention with a diluent (optional step) and by pouring the mixture obtained into soft or hard capsules. A preparation in the form of syrup or elixir may contain the extract according to the invention together with a sweetener, a flavoring agent and an appropriate color. The water-dispersible powders or granules can contain the extract according to the invention in admixture with suspending agents, as well as with flavor correctors or sweeteners. Advantageously, the composition according to the present invention is intended for oral administration.

Another object of the present invention is a composition according to the invention for its use as a medicament.

Another object of the present invention relates to an extract or a composition according to the present invention for its use for stimulating cell growth and promoting healing.

Thus, the invention also relates to a dermatological composition comprising an oyster extract according to the invention and an acceptable dermatological excipient, for its use for the treatment of scarring and skin irritation.

Indeed, it has been demonstrated that an extract according to the invention significantly promotes the synthesis of pro collagen by fibroblasts, which is one of the fibrillar proteins constituting an important part of the connective tissue involved in the healing of superficial skin wounds and in especially in scars from superficial injury, inflammation or skin irritation.

Indeed, skin repair begins within 24 hours of injury, inflammation or skin irritation, through the migration and induction of fibroblasts, and the proliferation of endothelial cells. In 3 to 5 days, the specialized granulation tissue characteristic of healing appears. Its histological appearance is characterized by a proliferation of fibroblasts and new thin-walled capillaries, often mixed with inflammatory cells, mainly macrophages. In the granulation tissue gradually accumulates more fibroblasts, which deposit more collagen, which results in the formation of a scar. The scar is reshaped over time.

The invention also relates to a method of cosmetic treatment, in particular non-therapeutic, of the skin intended to improve, prevent or treat cutaneous disorders comprising, or consisting of, the application to the skin of a cosmetic composition according to the invention .

The cosmetic treatment method according to the invention is characterized in that the improvement of skin disorders comprises the improvement of the signs associated with skin aging, in particular an effect chosen from: improvement of wrinkles, improvement of firmness of the skin and obtaining a skin tightening effect. The method of cosmetic treatment of the skin according to the invention is also characterized in that the improvement of skin disorders associated with skin aging comprises the treatment of age spots and the lightening of the complexion.

EXAMPLE 1: Oyster meat sample Environment of the sample: in a closed room.

Material to be sampled = milky oysters with "clean" shells (brush and rinse the shells well before opening);

Equipment and accessories = freezer bags + Ice bin which will be used to place the bags of oyster meat.

The oysters are opened and the flesh (coat, muscle, milt) is removed and then placed in a bag resting on ice.

Once closed, the bag is weighed and kept for another 30 minutes on ice before placing the sachet in the freezer at -18 ° C or -20 ° C.

EXAMPLE 2 Obtaining the Extract by Alkaline Hydrolysis and Characterization

The extract from alkaline hydrolysis is made from frozen "milky" oysters, kept in dry ice as soon as they are extracted from the shell.

The hydrolytic approach chosen is the alkaline route, and more particularly a 1 M NaOH solution.

The oyster flesh (approx. 200 g drained and thus freed of vegetable water) is mixed with 200 ml of a 1 M NaOH solution in order to obtain a pH of the solution of approximately 10 to 1 1.

After a contact time of 6 hours with stirring at room temperature and in the dark, the mixture is then neutralized with citric acid to obtain a pH of approximately 4.7. The mixture is filtered through a cellulose filter and then concentrated in vacuo so as to obtain 4 g of extract for 1 g of fresh oyster. The extract thus obtained has a dry matter content of 10%.

The extract obtained has the following characteristics:

Protein determination

Total proteins are tested according to the Lowry method. For this colorimetric assay, a standard curve DO750nm = f (quantity of proteins) is produced. The reference protein used during this experiment is bovine serum albumin (BSA). The determination of the total amount of protein in each extract is obtained using the same protocol as that carried out for the standard range.

Determination of polyphenols

Total polyphenols are evaluated according to the Folin Ciocalteu reagent method. For this colorimetric assay, a standard curve DO720nm = f is produced from increasing concentrations of a reference molecule. The reference polyphenol used during this experiment is gallic acid. The determination of the total quantity of polyphenols in each extract is obtained using the same protocol as that carried out for the standard range.

Sugar dosage

Total sugars are evaluated using the sulfuric acid and anthron hydrolysis method. For this colorimetric assay, a standard curve D0578nm = f is produced at from increasing concentrations of a reference molecule. The benchmark sugar used during this experiment is glucose. The determination of the total quantity of sugars in each extract is obtained using the same protocol as that carried out for the standard range.

EXAMPLE 3: STUDIES OF BIOLOGICAL PROPERTIES OF THE EXTRACT

The extract used is that obtained according to Example 1, having a dry matter content of 10%.

It is used after dilution in Ultra Pure water. The extract concentrations are: 0.5%, 1.5% and 4.5% w / v (in grams of extract per 100 mL of water).

Test on a test bench with collagen microbeads / Tensor effect measurement In this model, lyophilized collagen discs of 8 mm in diameter are used. The contraction of these discs in response to different treatments is measured by image analysis. The smaller the surface area of the collagen discs, the greater the tensor effect of the active ingredients.

The reference product used in this study is bovine serum albumin at 100 mg / ml.

The 8 mm diameter collagen discs are soaked with 40 mI of ultra pure water (control), the reference product, and increasing concentrations of the product under test.

• RESULT Tensor effect

• For extract at 1.5% / result + 49.4%;

• For Extract at 4.5% / result + 56.5%

Tests on normal human skin cell cultures / Melanin inhibition:

This study model uses normal human melanocytes obtained from the foreskin of a 4-year-old donor. Melanocytes are isolated and cultured in a monolayer until confluence. The cells are then incubated for 72 hours in the absence (Control) or presence of a reference product (positive control) or increasing concentrations of the product to be tested.

The reference product (positive controls) is Kojic acid at 250 mM.

At the end of the incubation period, the quantity of intracellular melanin is evaluated in the cell lysate by spectrophotometric measurement at 405 nm.

RESULT Melanin inhibiting effect:

0.5% extract; Result: -17.1%

Stimulating effect on the production of Pro-collagen type I

This study model uses normal human fibroblasts obtained from a 68-year-old donor woman. The fibroblasts are isolated and cultured in a monolayer until confluence. The cells are then incubated for 48 hours in the absence (control) or presence of a reference product (positive control) or increasing concentrations of the product to be tested.

The reference product (positive controls) is TGF-Beta at 1 ng / ml and 10 ng / ml.

After 48 hours of incubation, the amount of type I pro-collagen produced in the culture medium is evaluated using a sensitive and specific Elisa kit.

RESULT: stimulation of type I procollagen production:

0.015% extract; Income up 18%

These results confirm the positive effect of an extract according to the invention in the treatment of scarring following an injury or superficial skin irritation.

• Enzymatic tests

Collagenase Type I inhibitory effect

This test system is carried out using purified type I collagenases produced by Clostridium histolyticum, and a specific substrate detectable according to a colorimetric method. The consumption of this substrate by type I collagenases is monitored by measuring the OD (Optical Density) with a spectrometer at the wavelength of 405 nm every 3 minutes. The incubation period for these measurements is 45 minutes.

A reference control (namely 2.5 mM EDTA) was used to verify the modulation capacity and in particular the inhibition of enzymes in the test.

RESULT on Collagenase Type I inhibition

0.15% extract; result: - 67.3%

0.5% extract; result -82.2%

1.5% extract; result -91, 1%

Inhibitory effect on total collagenases

This test system is carried out using semi-purified collagenases originating from the culture medium of a culture of normal human fibroblasts, and of a specific substrate detectable according to a colorimetric method. The consumption of this substrate by total collagenases is monitored by measuring the OD (Optical Density) with a spectrometer at a wavelength of 405 nm every 3 minutes. The incubation period for these measurements is 45 minutes.

RESULT on total collagenase inhibition

0.5% extract; result -18.7%

1.5% extract; result -44.7%

CONCLUSION:

The extract (at 10% dry matter), and this from the dose of 1% shows a tightening effect which on the surface of the skin can bring a tension effect so as to erase wrinkles. The stimulation of the production of type I pro-collagen on fibroblast culture shows that the extract from alkaline hydrolysis of oyster flesh improves the content of the extracellular matrix of skin tissue by increasing the fibers associated with the firmness of the skin. This capacity also makes it possible to envisage filling in wrinkles. On the strength of this hypothesis, we rule out any decoy effect (the degradation of collagen fibers reactively stimulates the production of collagen, therefore any stimulation of the activity of collagenases could claim to indirectly stimulate the production of collagen).

This performance is reinforced by the capacity of the extract to stop the degradation of collagen by inhibition of the enzyme collagenase type I and more generally of all collagenases, any decoy effect is thus discarded, we observe a real biological capacity of the extract to stimulate pro-collagen type I. Finally, the extract makes it possible to limit the production of melanin from the dose of 0.5%, this property helps to limit age spots, but also to lighten the complexion .

Claims

1. Oyster extract obtained by alkaline hydrolysis of oyster flesh at pH between 8 and 13, particularly between 9 and 12 and without the addition of any external enzyme, particularly without the addition of external proteolytic enzyme.

2. Oyster extract according to claim 1 comprising in% by weight, relative to the dry matter of the extract, from 1% to 10% of free amino acids; from 3% to 12% of proteins or peptides, from 0.005% to 0.05% of total sugars and from 0.1% to 1% of polyphenols.

3. Dermatological or cosmetic composition comprising an oyster extract according to claim 1 or 2 and a dermatologically or cosmetically acceptable excipient.

4. Composition according to claim 3, characterized in that the amount of oyster extract is between 0.01% and 10% by weight relative to the total weight of the composition.

5. Composition according to one of claims 3 or 4, characterized in that the composition is in an oral or topical form, preferably in topical form.

6. Cosmetic composition according to one of claims 3 to 5 for its use in the prevention and / or treatment of skin disorders, said cosmetic composition comprising, as active principle, an oyster extract according to one of claims 1 or 2 in combination with a cosmetically acceptable excipient.

7. Composition for its use according to claim 6, characterized in that the skin disorders are manifested by changes in texture, color, transparency of the skin, and the appearance of wrinkles.

8. Composition for its use according to one of claims 6 or 7, characterized in that the skin disorders are consecutive to environmental stress.

9. Composition for its use according to claim 8 characterized in that the environmental stress is caused by the sun, tobacco.

10. Composition for its use according to one of claims 6 to 9, characterized in that the composition is in an oral or topical form, preferably in topical form.

1 1. Composition for its use according to claim 10, characterized in that the topical form is chosen from the group comprising creams, gels, ointments and sprays.

12. Composition for its use according to claim 10, characterized in that the oral form is chosen from the group comprising tablets, capsules and powders for oral suspensions.

13. Composition according to one of claims 3 to 5 for its use in improving the signs associated with skin aging, in particular chosen from: improving wrinkles, improving the firmness of the skin and obtaining of a skin tightening effect, the treatment of age spots and lightening of the complexion.

14. Dermatological composition comprising an oyster extract according to one of claims 1 or 2 and a dermatologically acceptable excipient, for its use for the treatment of scarring and skin irritation.