FR2894484A1 - Cosmetic composition useful as protective agent against harmful UV ray effects, comprises Cassia alata and Platanus occidentalis extracts - Google Patents

Abstract

Cosmetic composition comprises Cassia alata and Platanus occidentalis extracts. An independent claim is also included for a cosmetic care process to fight against the harmful effects of UV rays on the skin, comprising applying the composition on the skin.

Description

The present invention relates to a pharmaceutical composition

  cosmetic composition capable of protecting the skin from the harmful consequences of UV radiation containing two plant extracts: Cassia alata and Platanus occidentalis.

  An organism consists of billions of cells, basic units of a few microns, arranged to form the organs. Throughout the cell is stored about one meter of Deoxyribonucleic Acid (DNA), which is in the form of a double helix of polymers. DNA is the support of genetic information, coded by the succession of four nitrogenous bases A, T, C and G. The DNA molecule contains all the information necessary for the production of the proteins that living cells need. DNA undergoes multiple, unavoidable attacks from the intracellular environment and the environment, causing the formation of several thousand lesions per day and per cell. The sun emits electromagnetic radiation in a continuous spectrum ranging from cosmic rays to radio waves. Only a part of this solar spectrum penetrates the Earth's atmosphere. These are UV radiation, visible light (400 to 700 nm) and infrared radiation (above 700 nm). UVs represent about 10% of the radiation arriving at the surface of the earth but they are more energetic and therefore, the most biologically active. This radiation is itself subdivided into 3 zones: UVA (320-400 nm); UVB (280-320 nm) and UVC (200-280 nm).

  The shortest UVC and UVB are stopped by the ozone layer. The UV radiation that reaches our epidermis is made up of the longest UVA and UVB, knowing that there is 10 to 100 times more UVA radiation than UVB. The penetration of these UV in the skin is dependent on their wavelength. Indeed, the skin has a complex and heterogeneous structure that modifies the path and intensity of radiation by the conjunction of four elementary processes: reflection, diffraction, transmission and absorption. The UVB is mostly stopped by the stratum corneum and 10% reaches the dermis. In contrast, the majority of UVA cross the stratum corneum and 20-30% are transmitted to the papillary and reticular dermis. Connective tissue and fibroblasts therefore represent a major target of UVA radiation. UV is an essential part of our environment acting on the skin. UVB, the most energetic and mainly responsible for solar erythema, have long been considered as the only cause in the harmful effects of the sun on the body. We now know that UVA, a major source of free radicals, is also involved in the appearance of skin cancers and especially potentiate the effects of UVB. During exposure of the skin to UV radiation, many reactions will be activated. Oxidative stress plays a major role in the induction of these reactions. The absorption of UV, and more particularly of UVA, by an endogenous chromophore (flavins, quinones, NADPH ...) results in the production of very reactive small molecules: the activated species of oxygen (ROS) which induce a photooxidative stress in the cells. These ROS (102r 02'-, H202 and OH.), Activated species of oxygen are continuously produced in vivo (respiration) at low levels and are involved in physiological processes. They are, immediately after, degraded by enzymatic protection systems, thus ensuring an oxidative balance.

  UVAs generate an excess of ROS. UVBs also produce ROS but act by a direct mechanism as they are absorbed by DNA and proteins. This excess of oxygenated species has harmful effects on the cellular components (nucleic acids, proteins, polyunsaturated fatty acids, sugar, DNA). The process of DNA damage by UV radiation is the creation in the cell of unstable but highly reactive chemical species that oxidize the cell.

  These oxidizing agents can act on the DNA according to two different processes. In the first case, the oxidizing agents act directly on the DNA by ionization of this molecule, or on the water molecules bound to this biological polymer. This direct effect leads to local modifications of the double helix. Direct lesions are rather related to the action of UVB on DNA. These lesions result from the direct absorption of photons by the bases of DNA. Pyrimidine dimers, the main lesions induced on DNA by UV radiation, result in distortion of the double helix with implications for transcription, replication, and binding of proteins that bind to DNA.

  In the second case, the oxidizing agents act indirectly, by ionization of the water molecules. Created in the vicinity of DNA, powerful chemical oxygen reagents, free radicals such as the OH 'radical will alter the genetic material. Although these oxidizing species are very reactive, they have a very short life span, and only attack their immediate environment. They can either modify the bases of the DNA, leading to lesions, or attack the sugars that make up the DNA backbone and thus generate breaks in the chain, single or double-strand breaks. Depending on the amount of lesions on the DNA chain, the type of lesion (base modification, single break, double-strand break, etc.), the cell sets up repair mechanisms that are more or less effective. . If the repair is ineffective in the face of too much DNA damage, the cell goes into apoptosis, it is the cell suicide.

  This programmed death removes potentially mutated cells from the body, and thus prevents the proliferation of abnormal cells that are potentially cancerous.

  Thus a protective cosmetic composition capable of protecting the skin from UV must fight against these various phenomena.

  The work of the Applicant has made it possible to demonstrate that the combination of two plant extracts, an extract of Cassia alata and a Western Platanus extract effectively protect the skin from the deleterious effects of UV. The invention therefore particularly relates to a composition containing an extract of Cassia alata and an extract of Platanus occidentalis.

  The Cassia alata of the family of Caesalpinaceae, also called Golden Spike is a shrub native to tropical America that can reach 2 to 3 meters in height. His only requirement to grow is to be in full sun. Its leaves can reach 1 meter long and each leaflet can measure up to 15 cm. The Cassia alata extract used according to the invention is derived from a hydro-glycolic extraction of the leaves of the tree followed by purification. A dark brown opaque liquid with a pH of between 5 and 6.5 and a refractive index of 1.41 to 1.44 is then obtained. Platanus occidentalis is an ornamental tree up to 55 meters tall. The bark of the plane tree is gray to yellowish and exfoliates in gray plates. The extract of Platanus occidentalis used in the composition is derived from a glycolic extraction followed by pressing followed by clarification and sterilizing filtration of the bark of the tree. An amber liquid having a refractive index of 1.43 to 1.45 and having a solids content of 0.2 to 1% is then obtained.

  The composition according to the invention contains: on the order of 0.01 to 5% by weight, preferably 0.01 to 3% by weight, and most preferably 0.01% to 0.5% by weight, Cassia alata extract and - on the order of 0.01 to 5% by weight, preferably 0.01 to 3% by weight and most preferably from 0.01% to 0.5% by weight, of extract of Platanus occidentalis. The compositions according to the invention may advantageously contain tocopherol acetate. Also known as vitamin E, tocopherol acetate prevents skin aging associated with the sun. Indeed, this vitamin is a natural anti-oxidant that protects the skin from the harmful effects of free radicals produced in particular by UVB rays by blocking lipid peroxidation. It also improves the skin's elasticity and the skin's ability to retain water, which leads to a reduction in wrinkles and a rough appearance.

  The compositions according to the invention may also comprise one or more formulating agents or additives of known and conventional use in cosmetic and dermatological compositions such as, by way of examples and in a nonlimiting manner, UV filters, softeners, dyes, film-forming active agents, surfactants, perfumes, preservatives, emulsifiers, oils, glycols, vitamins, etc. Thanks to its knowledge in the field of cosmetics, the person skilled in the art will know which agents of formulation add to the compositions of the invention and in what quantities depending on the desired properties.

  The compositions according to the invention may be in any form known to those skilled in the field of cosmetology and dermatology with no other pharmaceutical restriction than the application on the face and body. Advantageously, the compositions according to the invention are in the form of a gel, a lotion, an oil, a cream, an emulsion, a milk, a spray, The invention also relates to the cosmetic use of a composition containing a Cassia alata extract and an extract of Platanus occidentalis as a protective agent for the deleterious effects of UV.

  The invention finally relates to a cosmetic care method for combating the deleterious effects of UV on the skin, characterized in that a suitable amount of a composition according to the invention is applied to the skin. In the context of the present invention, the term "adequate quantity" is intended to mean an amount capable of reducing and / or preventing the deleterious effects of UV on the skin, such as those previously described. Those skilled in the art know different methods for appreciating these improvements and in particular the methods used in the examples below.

  The following examples are given for illustrative purposes and can not be interpreted as limiting the scope of the invention. They concern, on the one hand, the evaluation of the DNA protection against UV by Cassia alata as well as the evaluation of the anti-radical effect of Platanus occidentalis with respect to fibroblasts and, on the other hand, examples of compositions that are the subject of the present invention.

  The examples refer to the following figures in which - Figure 1 shows a photo of non-irradiated control cell nuclei (Figure 1A) and irradiated at 20 J / cm2 (Figure 1B) - Figure 2 shows a photo of irradiated and protected cell nuclei with Cassia alata extract at 0.01. FIG. 3 represents a photo of irradiated cell nuclei protected by the 0.05% Cassia alata extract. FIG. 4 represents the effect of the Cassia alata extract (at 0.1 and 0.05%) on the protection of the cell nucleus after irradiation. The results shown in Figure 4A are calculated as the product of the percentage of DNA present in the tail by the length of the tail. Figure 4B graphically presents these results. - Figure 5 shows the anti-radical effect of Western Platanus (at 0.01, 0.05% and 1%) vis-à-vis normal human fibroblasts. The results are expressed in optical density unit. 1. EVALUATION OF THE EFFECT OF CASSIA ALATA ON THE PROTECTION OF NUCLEAR DNA FROM ULTRAVIOLET TEST OF 20 COMETES. The aim is to evaluate the effect of Cassia alata on the protection of nuclear DNA against ultraviolet rays. The protection of the DNA is evaluated by the comet test, the purpose of which is to measure the breaks induced directly by the UVA. This test makes it possible to establish the dose-effect relationship. It is an agarose gel electrophoresis test of isolated cells. After electrophoresis, the nuclei whose DNA has undergone breakage take a comet form and the nuclei whose DNA is undamaged remain round.

A. Materials and methods

1. Material

  The fibroblast cultures were established by the explant method, from healthy Caucasian skin samples (abdominoplasty.) The fibroblasts are cultured to sub-confluence, at 10 37 C, in a MEM (Minimum Essential Medium) medium. containing 2mM L-Glutamine and 10% fetal calf serum, in a saturated moisture atmosphere with 5% CO2, then after separation by buffered isotonic solution pH 7.2 0.1% trypsin and EDTA 0.02%, the cells are seeded in 60 mm diameter Petri dishes in the aforementioned medium The culture is maintained until subconfluence The cells are rinsed and incubated for 24 hours in different media as follows:

  MEM - Non-irradiated MEM light - Irradiated light *. MEM - Cassia alata 0.01% ** not irradiated. MEM - Cassia alata 0.01 ** irradiated. MEM - Cassia alata 0.05% ** not irradiated. MEM - Cassia alata 0.05 ** irradiated. (volume 2 ml). * doses of UVA irradiations = 20 J / cm2 (irradiator, Vilber Lourmat). ** Non-cytotoxic concentration revealed for MTT cells. Cell lots are then used for comet testing according to the described methodology. Method Superfrost slides are dipped at once in hot normal melting point agarose.

  The agarose on the underside of the blade is removed. The flat blades are dried and stored at room temperature until use. The cells are trypsinized and resuspended in PBS (phosphate buffer saline) at the density of 106 cells / ml. 10 μl (ie 10,000 cells) of cell suspension is deposited in 75 μl of low-melting agarose at 0.5 μg of this new cell suspension are deposited on the slides; the mixture is spread by gently depositing a large coverslip. Each blade is held for 30 minutes on a flat ice cream. Each slat is removed by gently sliding it. A third layer of 0.5% low-melting agarose (85 μL) is added and spread using a new coverslip. Each blade is held for 15 minutes on a flat ice cream. After removing the coverslip gently, the slides are immersed for 2 hours at 4 ° C. in a cold lysis solution. The drained blades are placed next to each other in the electrophoresis tank. The reservoirs are filled with electrophoresis buffer at pH> 13 to cover the slides. 20 minutes are enough to allow the progress of the DNA and the expression of the damage. The generator is energized at 24 V and the current is set at 300 mA. Electrophoresis takes place for about 10 minutes. The recovered slides are placed in a glass vessel and covered with 0.4 M Tris buffer to neutralize excess alkaline solution. The operation is repeated 3 times. The dye chosen is propidium iodide. This is diluted to 1 / 1000kme in PBS. A few drops per slide are deposited and each slide is covered with a coverslip object.

  All slats are fixed with varnish. The slides are ready for observation under a fluorescence microscope. (See Figures 1 to 3)

  B. Results The tail moment is defined as the product of the percentage of DNA present in the tail by the length of the tail (Figure 4). DNA extracted from non-irradiated cells is intact, not fragmented. Irradiation causes visible degradation of DNA. Treatment of the cells with Cassia alata at 0.01 and 0.05% effectively protects the DNA from ultraviolet light.

  C. CONCLUSION In our experimental conditions, the extract of Cassia alata very satisfactorily protects the cutaneous cells against the damage of the DNA after UV irradiation. The protection of DNA thus makes it possible to avoid mutations, replication errors and the persistence of induced damage leading to carcinogenesis and premature aging.30 II. EVALUATION OF THE ANTI-RADICAL EFFECT OF WESTERN PLATANUS ON NORMAL HUMAN FIBROBLASTS A. Materials and methods 1.Material Fibroblasts are cultured in the presence of the hypoxanthine enzymatic system (Sigma H-9636 Lot 10 26H1091) and xanthine oxidase (Sigma X-1875 Lot 101K3799). This system generates the superoxide anion which, in an aqueous acid medium, can be disproportionated to hydrogen peroxide. This hydrogen peroxide is cytotoxic from a certain concentration. The fibroblasts are isolated from normal human skin from an abdominoplasty. The culture is maintained in a humid atmosphere at 37 ° C containing 5% CO 2. 2. Method The cells are seeded in a 96-well plate, at a rate of 20,000 cells per well (confluence), in the presence of MEM + 10% fetal calf serum (constituting the attachment medium) and incubated for 24 hours. . We rinse and we change the environment by differentiating it. The culture medium used for the incubation of fibroblasts in the presence or absence of the hypoxanthine / xanthine oxidase system (HXXO) with or without the active ingredient is MEM. Fetal calf serum itself having a slight anti-radical effect is not added.

  In 96-well plate, the fibroblasts are incubated in different media as follows: MEM (control) MEM + XO 2mU / ml-HX 160 μg / ml MEM + XO 2 mU / ml-HX 160 μg / ml + 0 , 01% Platanus occidentalis extract - MEM + XO 2 mU / ml - HX 160 μg / ml + 0.05% Platanus occidentalis extract -MEM + XO 2 mU / ml - HX 160} zg / ml + 0.1% Platanus occidentalis extract After an incubation time of 30 minutes, the MTT colorimetric assay is performed: metabolized by the mitochondria to give blue formazan crystals, the amount of which depends directly on the activity of the enzyme mitochondrial succinate dehydrogenase and number of living cells. As a result, colorimetry (570 nm) is measured for metabolism and cell viability.

  B. Results The cell population decreases by more than 60% in the presence of the only free radical generator system. The results are shown in Figure 5. C. CONCLUSIONS In our experimental conditions, Platanus occidentalis extract, at all concentrations employed, almost completely preserves the cell population in culture exposed to the free radicals generated by the hypoxanthine / xanthine system. oxidase. (HXXO) III.EXAMPLES OF COMPOSITIONS PURPOSE OF THE INVENTION

  A. Photoprotective milk% CELLULOSE DERIVATIVE 0.50 GLYCERIN 5.00 DISODIC EDTA 0.10 C12-C15 ALKYL BENZOATE 3.00 ISODODECANE 2.00 ACRYLIC DERIVATIVE 0.10 TRIETHANOLAMINE 0.15 GLYCEROL MONOSTEARATE PEG-100 7.00 CETYL ALCOHOL 0.50 CYCLOMETHICONE 8.00 METHOXYBUTYL DIBENZOYLMETHANE 2.00 OCTYL METHOXYCINNAMATE 7.50 OCTOCRYLENE 7.00 POLYVINYL PYROLIDONE DERIVATIVE 2.00 VITAMIN E ACETATE 0.20 BHT 0.02 EXTRACT FROM WESTERN PLATANUS 1.00 CASSIA EXTRACT ALATA 1.00 PERFUME 0.50 DEMINERALIZED WATER QSP 100 B. CELLULOSE DERIVED PHOTOPROTECTIVE GEL 1,00 POLYISOBUTENE 6,00 10 15 OCTYL METHOXYCINNAMATE 7,50 OCTOCRYLENE 2,00 OCTYL SALICYLATE 5,00 C12ùC15 ALKYL BENZOATE 5,00 ISODODECANE 3 , 00 METHOXYBUTYL DIBENZOYLMETHANE 3.00 EXTRACT FROM WESTERN PLATANUS 1.00 CASSIA EXTRACT ALATA 1.00 CETYL ALCOHOL 0.60 VITAMIN E 0.20 PERFUME 0.40 ALCOHOL 96 QsP 15

Claims (6)

  1) Cosmetic composition characterized in that it contains an extract of Cassia alata and an extract of Platanus occidentalis.   2) Cosmetic composition according to claim 1, characterized in that the Cassia alata extract is a hydroglycolic extract.   3) cosmetic composition according to claims 1 or 2 characterized in that the extract of Cassia alata is an extract of the leaves of this plant.   4) Cosmetic composition according to claims 1 to 3, characterized in that the extract of Platanus occidentalis is a glycolic extract.   5) Cosmetic composition according to claims 1 to 4, characterized in that the extract of Platanus occidentalis is an extract of the bark of this plant.   6) Cosmetic composition according to any one of Claims 1 to 5, characterized in that it contains: on the order of 0.01 to 5% by weight, preferably 0.01 to 3% by weight, of Cassia alata extract and of the order of 0.01 to 5% by weight, preferably 0.01 to 3% by weight, of Platanus occidentalis extract. Cosmetic composition according to any one of claims 1 to 6, characterized in that it further comprises tocopherol acetate. 8) cosmetic composition according to any one of claims 1 to 7, characterized in that it further comprises one or more formulating agents or additives such as UV filters, softeners, dyes, film-forming agents, tensio active ingredients, fragrances, preservatives, emulsifiers, oils, glycols, and vitamins 9) Cosmetic composition according to any one of claims 1 to 8, characterized in that it is in the form of a gel, lotion, oil, cream, emulsion, milk or spray. 10) Cosmetic use of a composition containing a Cassia alata extract and a Western Platanus extract as a protective agent for the deleterious effects of UV. 11) Cosmetic treatment method for combating the deleterious effects of UV on the skin, characterized in that a suitable amount of a composition according to any one of Claims 1 to 9 is applied to the skin.