FR2911068A1 - Composition containing a unicellular alga of the genus Asterionella, plus caffeine and theobromine, used in cosmetic slimming formulations for topical application - Google Patents

Abstract

Compositions (I) containing (a) a unicellular alga of the genus Asterionella, (b) caffeine and (c) theobromine. Independent claims are also included for (1) a method (M1) for the production of (I) by centrifuging a culture of the algae, removing the supernatant and mixing the algal paste with the other components (2) a method (M2) for the production of (I) as in M1, except that the algal paste is resuspended and the suspension is mixed with the other components (3) a method (M3) for the production of (I) by making algal paste as in M1, splitting the algal cells, removing the membrane debris by a suitable method and mixing the cellular extract with the other components (4) cosmetic formulations containing (I) and a cosmetically-acceptable vehicle .

Description

The invention relates to a composition for inhibiting the enzyme

  phosphodiesterase involved in lipid metabolism.

  Phosphodiesterase is an enzyme found in adipocytes, involved in the processes of lipolysis (triglyceride degradation) and lipogenesis (synthesis and storage of triglycerides). It destroys cAMP that promotes lipolysis and disfavours lipogenesis. The action of the PDE inhibitors results in an increase in the level of intracellular cAMP, and therefore in lipolytic activity.

  Derivatives of xanthine such as caffeine and theophylline have been shown to be potent inhibitors of phosphodiesterase. Caffeine causes effects on the cardiovascular, respiratory and gastrointestinal systems. In addition, it works in skeletal muscles, renal blood flow, glycogenolysis and lipolysis. Caffeine is used in many cosmetic slimming formulations for topical use. Derivatives of xanthine are unfortunately poorly soluble in water, making their formation difficult and often leading to precipitation during storage. In addition, the incorporation of high concentrations of caffeine in cosmetic slimming products increases the frequency of the occurrence of undesirable side effects. These effects are the appearance of 25 red patches and in some cases small pimples accompanied by a sensation of burning, itching and tightness on the areas of application of the product. In some uncommon cases, the persistence of effects is greater than one week after cessation of use. It is therefore particularly advantageous to reduce the concentration of caffeine in such slimming cosmetic products to reduce the frequency and severity of undesirable skin effects.

  while maintaining a slimming activity at least identical to that of caffeine at the concentrations usually used.

  Now, the Applicant has now surprisingly discovered that the combination of a single unicellular alga with caffeine and theobromine makes it possible to obtain a PDE inhibitory activity that is much greater than that of caffeine alone. The amounts of caffeine used to obtain a higher or equivalent PDE inhibitory activity are therefore reduced in the composition according to the invention compared with the use of caffeine alone. The problems of the precipitation of caffeine during storage and the occurrence of undesirable side effects due to the high caffeine concentration are thus solved by the composition according to the invention.

  Based on this discovery, the object of the invention is to provide a composition for cosmetic use and capable of effectively inhibiting PDE, preferably more effectively than caffeine alone.

  A second object of the invention is to provide cosmetic formulations for topical slimming use.

  Thus, according to a first aspect, the subject of the present invention is a composition comprising a culture or paste of Asterionella algae, caffeine and theobromine. Unicellular algae of the genus Asterionella belong to the family of fragilariaceae. For the description of this family, one will be able to refer in particular to the Atlas of the Phytoplankton Marin of A. Sournia, published by the CNRS (1986).

  Theobromine is an alkaloid of the methylxanthine family. Its chemical formula is as follows: Theobromine is found in cocoa and chocolate. It is a stimulant frequently confused with caffeine, which nevertheless has a weaker but more prolonged effect than that of caffeine.

  Preferably, the culture medium of Asterionella is based on natural or synthetic seawater preferably having a salinity of between 2 and 70 g / l. A composition of this medium is for example the following: Seawater (total salinity 2-70 g / 1) qs-1000 ml NA2EDTA 30-60 mg / I H3BO3 20-40 mg / I Nitrate (K or NaNO3) 50- 2000 mg / I Dihydrogenphosphatase (K or NaH2PO4) 10-100 mg / I Si (Na2SiO3, 9H20) 10-50 mg / I Mn2 + 0.1-1 mg / I Theobromine 0-1000 mg / I Fe + 0.5-20 mg / I Zn2 + 5-200 μg / l Col + 5-150 μg / l Mo (NaMoO4, 2H20 for example) 1-20 μg / l Ass + 5-100 μg / l Thiamine 2-50 μg / l Pyridoxine 2-50 μg Cyanocobalamin 0.01-1 μg / l Biotin 0.01-1 μg / l. Advantageously, the culture is stopped when the concentration reaches about 50000 to 106 cells / ml. The harvest of the seaweed is generally carried out by centrifugation.

  The alga paste thus obtained can be used as it is. It can also be used to produce standardized unicellular algae suspensions. Or, the algal cells of the seaweed paste are exploded and the membrane debris is removed by an appropriate separation technique (centrifugation, filtration) to produce a cell extract. The compositions of the invention are characterized by a cell concentration generally ranging between 105 and 1010 cells or biomass equivalents per ml. The suspension medium preferably consists of the culture medium and an alcohol or polyol alone or in a mixture chosen from ethanol, propanol, isopropanol, propane-1,2-diol and propane-1. 3-diol, butane-1,2-diol, butane-1,3-diol, butane-1,4-diol, methyl-2-propane-1,3-diol, glycerol. Said alcohol or polyol is generally present in the composition at a concentration of between 10 and 60% by weight in order to avoid the use of a preservative.

  Advantageously, the caffeine is present in a proportion of 0.2 to 4%, preferably 1 to 3%, in particular 2% by weight of the composition. Advantageously, theobromine is present in a proportion of 0.005 to 5%, preferably 1 to 4%, in particular 2% by weight of the composition. It should be emphasized that it is specifically the combined use of a unicellular alga, caffeine and theobromine which leads to the inhibitory effect of the PDE observed with the composition according to the invention. This combination has a significantly higher PDE inhibitory effect than either seaweed alone, caffeine alone or theobromine alone.

  Advantageously, the alga Asterionella is the particular species Asterionella japonica.

  A process for preparing a composition according to the invention is a further object of the present invention. In such a preparation process, the unicellular alga is prepared beforehand, either in the form of an algae paste, or in the form of a cell suspension, or in the form of a cell extract as described above. The algae preparation is then mixed with the other components of the composition, in particular caffeine and theobromine.

  Another object of the present invention is the use of the compositions according to the invention for preparing cosmetic formulations. Such cosmetic formulations are also part of the invention.

  In order to ensure an optimal effect within the cosmetic formulation in which it is incorporated, the composition according to the invention is generally used in said formulation in a proportion of 0.1 to 100% by weight. Preferably, the unicellular alga is present within the cosmetic formulation obtained at a rate of 104 to 108 cells or cell equivalents per ml.

  We are talking about x cell equivalents for a cell extract after removal of the mernbranary debris from x cells. The cosmetic formulations according to the invention may comprise, in addition to the compositions according to the invention, other ingredients and one or more cosmetically acceptable vehicles.

  By cosmetically acceptable vehicle is meant a vehicle adapted for use in contact with the various superficial parts of the human body and in particular the epidermis, without toxicity, irritation, undue allergic response and the like, and proportionate to a reasonable risk / benefit ratio.

  Such cosmetic formulations according to the invention are generally in the form of lotion, emulsion, cream, gel or patch. Preferably, such cosmetic formulations according to the invention are in the form of an emulsion. These emulsions may be water-in-oil (W / O) or oil-in-water (O / W) emulsions, microemulsions, nanoemulsions. They can incorporate liposomes or capsules. They may be in the form of a fluid with very viscous or in solid form. It is within the skill of the person skilled in the art to determine the nature of the additional component (s) to be used in the formulations of the invention in view of the type of cosmetic formulation that it wishes to obtain.

  Another subject of the invention is the use of a cosmetic formulation according to the invention for topical application for inhibiting PDE. Preferably, the cosmetic formulation according to the invention is used in topical application for thinning. Said formulation is then applied to the areas of the body that one wishes to thin. The components of the composition according to the invention present in the formulation exhibit a synergistic inhibitory action of PDE. As a result, cAMP levels and lipolysis increase.

  The following examples illustrate the invention without limiting its scope. Examples 1 and 2 show the percentages by weight of each component of cosmetic formulations according to the invention. EXAMPLE 1 Lotion

  Benzophenone 9 0.1 Maris aqua (seawater 17 g / I) qs 100 Methylpropanediol 6 Disodium EDTA 0.2 Acacia 2 Xanthan gum 0.6 Allantoin 0.1 Lysine (50%) 0.3 Asterionella extract 10.106 cells / ml, ethanol 30%, caffeine 2%, theobromine 2% 10.0 Octyldodeceth30 0.8 Fragrance 0.15 Potassium sorbate 0.2.

  EXAMPLE 2 Fluid Emulsion Asterionella Extract at 10 × 10 6 cells / ml, 30% ethanol, 2% caffeine, Theobromine 2% 10.0 Disodium EDTA 0.4 Xanthan Gum 0.4 Carbomer 0.4 Potassium Hydroxide 0.2 Methylpropanediol 4 Glycerin 2 Panthenol (75%) 1 Cetearyl glucoside 0.5 Behenyl alcohol 1 Stearyl alcohol 0.8 Cetyl alcohol 1.5 Pentaerythrityl distearate 3 PEG-100 stearate 0.8 Ethylhexyl cocoate 3 Jojoba oil (Simmondsia chinensis) 5 Glycine soy (soybean) sterols 0.5 Hexyldimethicone 4 Cyclopentasiloxane 5 sodium mannuronate methyl silanol 10 Lalinaria digitata extract 5 Potassium sorbate 0.2 Benzoic acid 0.3 Fragrance 0.6

  EXAMPLE 3: Measurement of PDE Activity The activity of phosphodiesterase is assayed according to the method of Thompson and Applemann (Biochemistry 10: 311-316, 1971). Preparation and characterization of the extract enriched with PDE: human adipose tissue from the operating residue obtained after cosmetic surgery is homogenized and then centrifuged to eliminate the adipose phase. The infranant is then ultra-centrifuged, aliquoted and frozen at -80 ° C. The amount of total proteins of the extract is measured according to the method of Lowry. The study of the linearity of the cAMP hydrolysis as a function of the incubation time and the quantity of proteins makes it possible to define the optimal conditions for the determination of the IC50, that is to say the concentration active ingredient at which 50% inhibition of PDE is observed. Reference product: caffeine diluted in the reaction buffer (50 mM TRIS, pH 7.5, 5 mM MgCl 2). Test products: freeze-dried compositions suspended in the 10% w / v reaction medium. After determining the osmolarity, an aliquot quantity is dialyzed extensively against the reaction medium using a membrane whose cut-off point is 100 daltons. The product of the dialysis is measured and supplemented with the aid of reaction medium to obtain a total dilution of 5%. 1. Pure caffeine shows an IC50 of 0.45 mM or 0.0086% 5 (w / v) 2. Pure theobromine shows an IC50 of 0.0115% (w / v) 3. An asterionella extract with 400.106 cells per ml in its culture supernatant (theobromine 0%) and 20% freeze-dried ethanol and prepared as indicated above shows an IC50 of 0.17% w / v (ie about 5% of the caffeine activity). 4. An asterionella extract at 400.106 cells per ml in its culture supernatant (theobromine 0.02%) and 20% ethanol supplemented with 2% by weight of caffeine and 2% by weight of theobromine is freeze-dried.

The caffeine dosage in the dialysis product (prepared as indicated above) is 0.32%. The IC50 of the dialysis product is 0.43% (w / v). The dialysate dilution factor corresponding to the IC50 is 235.

The caffeine concentration at the IC50 concentration of the asterionella-caffeine-theobromine complex is therefore 0.0014% (0.32% / 235). The inhibitory activity of the composition according to the invention is therefore about six times higher (0.0086 / 0.0014) than that of caffeine.

Theobromine assay in the dialysis product (prepared as indicated above) is 0.663%. The concentration of theobromine at the IC50 concentration of the asterionella-caffeine-and-ethobromine complex is therefore 0.00289% (0.663% / 235).

The inhibitory activity of the composition according to the invention is therefore about four times higher (0.0115 / 0.0028) than that of theobromine.

Claims (13)

  1. A composition comprising a unicellular alga of the genus Asterionella, caffeine and theobromine.   2. Composition according to claim 1, characterized in that the cell concentration is between 105 and 1010 cells or biomass equivalents per ml. 10   3. Composition according to any one of claims 1 to 2, characterized in that the caffeine is present in a proportion of 0.2 to 4% by weight of the composition.   4. Composition according to any one of claims 1 to 3, characterized in that theobromine is present in an amount of 0.005 to 5% by weight of the composition.   5. Process for the preparation of a composition according to any one of claims 1 to 4, characterized in that: - a culture of algae Asterionella is harvested by centrifugation - the supernatant is removed - the algae paste thus obtained is mixed with the other components.   6. Process for the preparation of a composition according to any one of claims 1 to 4, characterized in that: - a culture of algae Asterionella is harvested by centrifugation - the supernatant is removed - the algae paste thus obtained is resuspended - said suspension is mixed with the other components. 30   7. Process for the preparation of a composition according to any one of Claims 1 to 4, characterized in that: a culture of Asterionella algae is harvested by centrifugation, the supernatant is eliminated, the algal cells of the The resulting algae paste is broken up, the membrane debris is removed by an appropriate separation technique, the cell extract thus obtained is mixed with the other components.   8. Use of a composition according to any one of claims 1 to 4 for the preparation of a cosmetic formulation.   9. Use according to claim 8, characterized in that said composition is used in said cosmetic formulation in a proportion of 0.1 to 100% by weight.   Cosmetic formulation comprising a composition according to any one of claims 1 to 4 and a cosmetically acceptable carrier.   11. Cosmetic formulation according to claim 10, characterized in that the unicellular alga is present in a proportion of 104 to 10 $ cells or cell equivalents per ml of said formulation.   12. Cosmetic formulation according to any one of claims 10 and 11, characterized in that said formulation is a lotion, an emulsion, a cream, a gel or a patch.   13. Use of a cosmetic formulation according to any one of claims 10 to 12 for topical application for thinning. 30