BE1018697A3 - COSMETIC COMPOSITION WITH TOPICAL APPLICATION COMPRISING HYALURONIC ACID. - Google Patents

Abstract

Cosmetic composition for topical application comprising hyaluronic acid, characterized in that said hyaluronic acid is encapsulated in nanosomes.

Description

"COSMETIC COMPOSITION WITH TOPICAL APPLICATION

COMPRISING HYALURONIC ACID "

The present invention relates to a cosmetic composition with topical application comprising hyaluronic acid.

Hyaluronic acid is a glycosaminoglycan (the simplest and without sulfate group) found naturally in the connective, epithelial and nervous tissues. It is one of the major components of the extracellular matrix and contributes significantly to cell proliferation and migration.

Hyaluronic acid is a polymer of hyalobiuronic acid, more particularly a polymer of disaccharides themselves composed of D-glucuronic acid units and D-N-acetylglucosamine units. These units are linked together by alternating β-1,4 and β-1,3 glycoside linkages. The hyaluronic acid found in vivo has a size between 102 and 104 kDa and comprises about 50,000 dissachable units.

In addition to the well-known ophthalmic applications, hyaluronic acid is used in aesthetic medicine as a wrinkle-filling product and in post-operative care to promote the reconstitution of tissues or as an anti-wrinkle product.

A composition as mentioned at the beginning is for example known from WO 2008/015249 which uses hyaluronic acid together with a polyamine to provide a cosmetic composition with improved penetrating power because the polyamine in combination with hyaluronic acid allows the association of particles in micellar form which results in a colloidal composition with high penetrating power.

However, there is a need to provide a composition that still allows for improved intradermal penetration and enhanced anti-wrinkle effect.

The composition according to the invention aims to overcome the drawbacks of the state of the art by providing a composition in which said hyaluronic acid is encapsulated in nanosomes.

Nanosomes are very small liposomes, which have a structure similar to that of cell membranes, that is, they are formed by a phospholipid bilayer.

The phospholipids have a hydrophilic head formed of a phosphate group and a hydrophobic tail formed of a lipid moiety.

When the phospholipids are immersed in the water, they orient themselves in such a way that the hydrophilic heads are directed towards the surrounding water molecules and their hydrophobic parts move away as far as possible. It is these particular properties of the hydrophilic-hydrophobic structure that gives them the ability to orient bilayer when the phospholipids are immersed in water.

The nanosomes are in the form of small beads with a hydrophilic envelope, having two concentric cavities. The outer cavity, but covered with the hydrophilic envelope, is a hydrophobic cavity, while the cavity concentric with the external cavity is the internal cavity which is itself hydrophilic.

The nanosomes thus have the capacity to encapsulate and transport soluble molecules in water in the internal hydrophilic cavity (polar cavity) and molecules soluble in an oily phase in the external cavity, non-polar and therefore hydrophobic.

According to the invention, the hyaluronic acid will be encapsulated in the hydrophilic part of the nanosomes, that is to say in its polar inner core.

Because of their structure close to the cell membrane, the nanosomes penetrate easily into the structure of the skin and can deliver their contents to the cells.

In this way, the penetration of hyaluronic acid into the inner layers of the epidermis will be improved. In addition, the nanosomes consist of membrane components and therefore, their topical application makes it possible to provide cell membranes with components such as phosphatidylcholine, sphingomyelin or other phospholipids for regenerating the membranes of the cells and therefore, the combination of these nanosomes with hyaluronic acid allows an anti-wrinkle effect amplified on the one hand by a better penetration of the hyaluronic acid and thus a better filling role "anti-wrinkles" and on the other hand by the supply of component of the cell membranes to fight against aging.

In an advantageous embodiment, the composition according to the invention also comprises a synthetic hexapeptide which further increases the penetration efficiency of the composition according to the invention, for example by comprising a sequence which is a cell penetration signal peptide. or by providing a relaxing effect which promotes the penetration of the composition according to the invention.

In another advantageous embodiment, said synthetic hexapeptide is an acetyl-hexapeptide which has the following sequence Ac-EEMQRR-Nhb presented in the attached sequence listing under the reference number SEQ ID No. 1.

Acetyl hexapeptide is an analogue of botulinum neurotoxins, which has a remarkable anti-wrinkle efficacy, but without the toxicity of botulinum neurotoxins.

Acetyl hexapeptide inhibits the release of the neurotransmitter and therefore produces effects similar to those of botulinum neurotoxins, although in the short term, but without the toxicity of the aforementioned neurotoxins.

The inhibition of neurotransmitters is due to the interaction of said acetyl hexapeptide with the formation of the protein complex required for calcium-dependent exocytosis (cell fusion complex) which makes it possible to reduce the extent of expression lines.

In addition, said acetyl hexapeptide, because of its small size has a penetrating power through the dermis which is very high, which makes it possible to increase the effectiveness of the composition according to the invention in its anti-wrinkle action since none of the compounds which constitute it do not remain on the surface and penetrate relatively deeply to have an action in depth.

In a particular embodiment, said synthetic hexapeptide is present in a concentration of about 500 ppm, which amounts to a concentration of 0.5 g / kg, which is a relatively high amount for such an effective active ingredient. allowing, since the latter has no toxicity to improve the effectiveness of the composition.

In an advantageous variant according to the invention, hyaluronic acid is a polymer having a molecular weight of between 20 kDa and 80 kDa, preferably between 35 kDa and 65 kDa and more preferably about 50 kDa.

When hyaluronic acid is present in the form of a polymer of this small size, its filling effect is improved because, in cells, hyaluronic acid is degraded by hyaluronidases which are of several types. The degradation products of hyaluronic acid, oligosaccharides and hyaluronic acid polymers of very small size can still penetrate deeper into the dermis of the skin and therefore have a deep wrinkle filling efficiency, which lasts longer. long and is really visible (filling below the epidermis).

In addition, the degradation products of hyaluronic acid continue to tissue hydrodynamics, cell movement and proliferation. The degradation products of hyaluronic acid interact with CD44 receptors and therefore they stimulate fibroblasts and thus the production of collagen which improves the elasticity of skin tissues. In addition, the action on cell movement and proliferation improves cell renewal, which promotes the anti-aging effect of the composition according to the invention.

In an advantageous embodiment, the composition according to the invention further comprises one or more surfactants, preferably selected from the group consisting of polyethylene glycol, caprylic acid, caprylic capric triglycerides, capric / caprylic triglycerides, and other cationic analog surfactants, anionic or amphiphilic, which makes it possible to improve the shelf life and the stability of the composition according to the invention.

Preferably, the composition according to the invention further comprises ethyl alcohol present in an amount ranging from 5 to 15% by weight, relative to the weight of the composition and preferably about 10% by weight. Therefore, the composition according to the invention does not include an antibacterial agent harmful to the natural flora of the skin or other compounds and contains only alcohol, which makes it a particularly well-tolerated composition, little allergenic and accessible for any type of person.

Other embodiments of the composition according to the invention are indicated in the appended claims.

The invention also relates to a process for the preparation of a cosmetic composition for topical application comprising the steps of: - formation of a stable microemulsion, - production of nanosomes containing said hyaluronic acid, - mixing of the stable microemulsion and nanosomes containing said hyaluronic acid.

In a preferred embodiment, the method according to the invention further comprises the steps of - forming an aqueous phase comprising the acetyl hexapeptide and adding the aqueous phase comprising said acetyl hexapeptide to said mixture of the stable microemulsion and nanosomes containing said hyaluronic acid.

Advantageously, said stable microemulsion comprises the following components, PEG-8 caprilic / capril triglyceride, polyglyceryl-6-diolate capric and caprylic triglycerides.

In a preferred embodiment, said aqueous phase containing said acetyl hexapeptide comprises water and ethyl alcohol.

In a preferred embodiment, the nanosomes comprise lecithin.

Other embodiments of the process according to the invention are indicated in the appended claims.

Other features, details and advantages of the invention will emerge from the description given below, without limitation and with reference to the appended example.

EXAMPLE.-

A composition according to the invention was made from three preformed compositions which are mentioned below as compositions A, B and C presented in Tables 1 to 3.

Table 1.-

Table 2.-

Table 3, -

% by weight =% by weight relative to the total weight of the composition according to the invention.

It is understood that the present invention is in no way limited to the embodiments described above and that many modifications can be made without departing from the scope of the appended claims.

Claims (7)

1. Cosmetic composition for topical application comprising hyaluronic acid, characterized in that said hyaluronic acid is encapsulated in nanosomes. 2. The composition of claim 1, further comprising a synthetic hexapeptide. 3. A composition according to claim 1 or claim 2, wherein said synthetic hexapeptide is an acetyl hexapeptide which has the sequence SEQ ID NO 1. The composition of any preceding claim, wherein said synthetic hexapeptide is present at a concentration of about 500 ppm. 5. The composition as claimed in any one of the preceding claims, in which the hyaluronic acid is a polymer having a molecular weight of between 20 kDa and 80 kDa, preferably between 35 kDa and 65 kDa and more preferably about 50 kDa. kDa. 6. Composition according to one of the preceding claims, further comprising one or more surfactants, preferably selected from the group consisting of polyethylene glycol, caprylic acid, caprylic capric triglycerides, capric / caprylic triglycerides, and other surfactants. cationic, anionic or amphiphilic analogues, A composition according to any one of the preceding claims, further comprising ethyl alcohol present in an amount of from 5 to 15% by weight, based on the weight of the composition and preferably about 10% by weight. .