EP0810867A1

EP0810867A1 - Novel use of compositions containing mother-of-pearl

Info

Publication number: EP0810867A1
Application number: EP96943169A
Authority: EP
Inventors: Gilles Gutierrez; Evelyne Lopez; Christian Milet; Mostafa Serrar
Original assignee: Texinfine SA
Current assignee: Texinfine SA
Priority date: 1995-12-21
Filing date: 1996-12-20
Publication date: 1997-12-10
Also published as: FR2742661B1; WO1997023231A1; CA2214095A1; AP9701086A0; JPH11501055A; FR2742661A1; NO973826L; NO973826D0; IL121576A0; BR9607043A; PL321870A1

Abstract

A novel use of mother-of-pearl in medicine and/or cosmetics in disclosed. A fine powder consisting of mother-of-pearl and optionally aragonite is mixed with suitable carriers and used to prepare pharmaceutical and/or cosmetic compositions for improving the synthesis of novel cytokeratins. The use of a fine powder consisting of mother-of-pearl and optionally aragonite mixed with suitable carriers for improving the synthesis of novel cytokeratins in cell culture media is also disclosed.

Description

NEW USE OF NACRE-CONTAINING COMPOSITIONS

The invention relates to a new use of mother-of-pearl for medical and / or cosmetic purposes.

The Chemical Abstracts, Vol. 124, No. 11, 1996, p. 1084 describes a preparation of mother-of-pearl combined with keratin; this preparation is obtained by lactic acid digestion of powdery mother-of-pearl, which destroys the mineral component of mother-of-pearl.

The reference US-A-4,393,045 (EG HENDERSON et al.) Relates to components of mother-of-pearl having a curative effect, by application of a preparation obtained after contacting a fruit containing citric acid with the shell of a mollusc containing the pearly part. Only the organic part of the mother-of-pearl is preserved.

The reference EP-A-0 393 267 (M. KATO et al.) Describes a bioactive substance obtained by heating the mother-of-pearl for several hours at very high temperature. This heating appears to activate a plant and animal growth agent.

The reference WO-A-95 30426 (S. CAMPRASSE et al.) Relates to a product for skin regeneration and healing, obtained from a ground material of the pearly test and a lyophilisate from animal cells which are treated with enzymatic and thermal route. The reference DE-A-34 37 184 (E. IWAN et al.) Relates to an agent for treating burns based on a mixture of pulverized shells of mussels and snails. The shells are washed beforehand with water and dried. This mixture has an antibacterial action. Patent FR-A-2 715 568 (J. VIRASSAMY) claims the use of mother-of-pearl powder for bone reconstruction.

Mother of pearl has been known for a long time for its regenerative properties of bones. The Applicant has found that mother-of-pearl contains in its crystal structure substances capable of activating the cells of the animal and in particular of making it possible to repair the shell of conchifers when it is injured. Certain substances contained in the biomineral which is mother-of-pearl are of a protein nature and respond well to the antibodies directed against human and rat collagens, type I and III. There is therefore an analogy between the skin and the shell of conchifers. On the basis of this observation, the Applicant has studied and verified that the mother-of-pearl contains original substances which could intervene in the processes of restructuring, stimulation, etc., of the skin.

The need to give the skin a stimulated or rejuvenated appearance has so far used treatments which remove the superficial stratum corneum, in order to reveal the underlying cellular layers. This is how we give the skin a rejuvenated appearance, but with the triple consequence: - to refine the skin by a thinning of the epidermis while it sees its thickness decrease with age,

- to decrease the number of cells in the epidermis, thus undermining the cell replication capital,

- to remove the apoptotic or dead cells from the superficial part of the epidermis, thus eliminating the protective film of the stratum corneum and more particularly of the stratum disjunctum, sensitizing the skin to external aggressions.

Other care techniques call on strictly visual aspects, such as the deposit of an iipophilic or silicone film, shiny or satin, which seals the outer layers and thus prevents their dehydration. Finally, the changes in skin color ensure a warmer (tan) or juvenile (whitening) appearance by often being combined with sun protectors (organic or mineral screens) or natural or artificial tanning stimulants (Dihydroxyacetone or DHA ). These treatments do not contribute in any way to improving the natural quality of the skin since they are, in fact, only make-up. This is why the present invention aims to solve the technical problem which had not been resolved hitherto, to present on the surface of the skin a neoformed structure which gives it a young and dynamic appearance without eliminating the cells.

The Applicant has studied the consequences of the use of mother-of-pearl on other types of cells such as fibrobiasts, lymphocytes, keratinocytes and endothelial cells.

The observation of cellular behaviors made it possible to note the appearance of new properties not described to date and which make it possible to use mother-of-pearl for these new uses.

Indeed, the pearl powder added in the culture of keratinocytes unexpectedly causes an increased synthesis of cytokeratins.

The structure present on the skin surface must be a substance naturally produced by epithelial cells, such as keratinocytes, which contributes to the physiological thickening of the epidermis.

The solution chosen was to choose not to strip the skin to bring new cell structures to the surface, but to make keratinocytes produce newly formed substances, the cytokeratins, which normally generate these cells when they are young or active.

These protein substances thus contribute to the thickening of the epidermis by improving the cytopiasmic quality of keratinocytes as well as of corneocytes, and consequently its passive resistance to external aggressions. In addition, the restructuring of the epithelial stratum improves the mass of the epidermis, thus constituting a reserve of messengers and contributing to its active resistance to external aggressions.

The most superficial part of your skin is made up of anucleated cells, the outermost layers of which form the Stratum corneum. This outer horny layer can be like the shell of bivalves. There is therefore every reason to think that the processes of restoration of this structure, (consisting of matter without nuclear and genetic material like the shell), can respond to the same restoration signals. However, there remains a difficult problem to solve since the shell of bivalves bathes in water and the substances released from the shell on the occasion of a lesion must respond to a very specific action specificity. As a result, the studies carried out by the Applicant have encountered numerous difficulties in expressing and highlighting this activity.

Analysis of the proteins after traditional crushing of the mother-of-pearl shows that it can contain 1.6 mg of protein substances per gram. It has been found that these substances do not develop, according to the dilution, the same activity (alkaline phosphatase) on an osteoblast culture. In addition, it was unexpectedly noted that if the mother-of-pearl powder is diluted with another powder consisting essentially of aragonite (mineral constituent of mother-of-pearl), the response of the cells to the presence of mother-of-pearl biocrystals finds amplified. It is therefore with a preparation consisting of mother-of-pearl and aragonite that the tests described below were carried out. Depending on the desired effect, it is possible to use dilutions with a variable percentage of mother-of-pearl in the total mixture.

The present invention more specifically consists in the use of a powder formed of mother-of-pearl and optionally of aragonite, in finely pulverulent form and mixed with suitable excipients, for the production of pharmaceutical and / or cosmetic compositions intended to improve the synthesis of new cytokeratins.

The invention also consists in the use of a powder formed of mother-of-pearl and optionally of aragonite, in finely pulverulent form and mixed with suitable excipients, with a view to its application in cell culture media in order to improve synthesis. new cytokeratins.

The very important synthesis of new cytokeratins ensures the improvement of the qualities and appearance of the skin, and in particular makes it possible to ensure the processes of restoration of the structure of the skin, to exert a protective role on the skin and to give it active resistance in aggressive outdoor conditions (sun, cold, prolonged exposure to water, etc.), to improve properties mechanical skin, giving it a youthful and dynamic appearance, thanks to a newly formed structure on the surface.

The powder formed of mother-of-pearl and aragonite is constituted such that the mixture contains mother-of-pearl in a proportion ranging from 0.1% to 98% in the total mixture, and preferably in a proportion ranging from 5 to 20% in the total mixture.

The tests described below were preferably carried out with a preparation consisting of 10% mother-of-pearl and 90% aragonite. The present invention also relates to pharmaceutical and / or cosmetic compositions ensuring the improvement of the qualities and appearance of the skin, characterized in that they consist of mother-of-pearl, optionally added with aragonite, in combination or in mixture with an inert, non-toxic, powdery excipient or diluent.

If mother-of-pearl makes it possible to develop a dermo-protective effect, it is in the synthesis of the constituents of the Stratum corneum that we find the most modifications. Since the stratum corneum is formed by the condensation of cytokeratins, the Applicant has directed its analyzes towards this material. The possible consequences are essentially in the quality of the response of cells to the stress of an aggression (synthesis of interleukin 1: IL-1). In addition, the skin is subjected to an important photoluminous activity to which it responds by the synthesis of a photoprotective element: melanin. There is therefore a decrease in the synthesis of melanin or a better distribution of the latter in keratinocytes.

Role of mother-of-pearl in the synthesis of cytokeratins

Cytokeratins are distinguished by their molecular weight and for most of them there is a specific antibody. In order to study the whole phenomenon, an antibody was used against all of the cytokeratins. Because of this, it is called anti-pan cytokeratins.

A cell culture of keratinocytes obtained from surgical skin samples was therefore carried out. The skin is treated by enzymatic digestion and incubation in a specific medium (modified Mac Koy or of the KBM-Basai Medium Keratinocyte type): culture medium containing no serum.

10 ⁵ cells are incubated for 24 hours in the presence of 50 mg of nacre per ml of medium devoid of fetal calf serum or similar protein serum. The cells are rinsed, the supernatant eliminated, the cells are separated from the mother-of-pearl, lysed, then a "Western Blot" is carried out on the cell fraction. The “Western Blot” technique is an analytical technique based on the separation of proteins according to their molecular weight by electrophoresis followed by immunological detection. A second layer antibody grafted to an enzyme reveals the first antibody when contacted with a chromogenic substrate. To obtain interpretable results, several dilutions are tested and the quantification of the substance to be assayed, here pan cytokeratins, is done by simple absorption spectrophotometry or by image analysis of the revelation plate. Under these conditions, it was found that the basic hypothesis was verified and that the nacre was capable of doubling the quantity of cytokeratins synthesized by the keratinocytes. The results are studied taking into account the total protein synthesis over several dilutions, because on the one hand the number of cells is not strictly constant, and on the other hand their activity is not necessarily coordinated.

Total proteins (in μg) volume tested in μl: 10 20 40 control (without mother-of-pearl) 8 9.3 18.3 mother-of-pearl 3 7.5 12

Cytokeratin signal volume tested in μl: 10 20 40 control (without mother-of-pearl) 62.8 70.9 178 mother-of-pearl 18.4 108,275

Cytokeratin signal (X 10) / Total proteins volume tested in μl: 10 20 40 control (without mother-of-pearl) 78 76 97 mother-of-pearl 61 130 230 Mother-of-pearl / volume control ratio tested in μl: 10 20 40 ratio 0.78 1.89 2.36

We therefore note that mother-of-pearl increases the synthesis of pan cytokeratins by a multiplicative factor of the order of 2.

Figure 1 is a graphical representation of the evolution of the synthesis of pan cytokeratins as a function of the volume tested. There was shown the signal cytokeratin X 10 / μg total protein ratio for the control and for mother-of-pearl preparations.

It will be noted that the analysis takes on all of its sensitivity during the electrophoresis of at least 20 μl.

If the synthesis of cytokeratins improves the mechanical properties of the skin, it is possible to consider a protective role for mother-of-pearl during attacks. Two types of response to aggression can be considered: responses to chemical or biological aggressions involving interleukin in first intention and responses involving melanin.

Role of mother-of-pearl on the synthesis of interleukin 1 (IL-1):

FIG. 2 represents the results obtained during the culture of the cell line

HL 60 in the presence of mother-of-pearl.

There is a significant decrease in the secretion of IL-1 when the cells are cultured in the presence of nacre.

Protective reaction involving melanin

The culture of melanocytes (ECACC line) line G 361 in the presence of mother-of-pearl only slightly modifies the secretion of melanin.

Average control 0.150 0.149 0.148 0.149 mother-of-pearl 0.5% 0.150 0.132 0.140 0.141 mother-of-pearl 1% 0.139 0.137 0.143 0.141 However, it is noted that the number of melanocyte dendrites is increased during the melanocyte-keratinocyte coculture originating from skin explants.

(number of dendrites) witness 5 mother-of-pearl 0.2% 12 mother-of-pearl 1% 15

We deduce a better distribution of melanin.

Claims

1 Use of a powder formed of mother-of-pearl and optionally of aragonite, for the production of pharmaceutical and / or cosmetic compositions intended to improve the synthesis of new cytokeratins.

2. Use of a powder formed of mother-of-pearl and possibly aragonite, with a view to its application in cell culture media in order to improve the synthesis of new cytokeratins.

3. Use of a powder formed of mother-of-pearl and optionally aragonite according to claims 1 and 2, in which the powder is constituted such that the mixture contains mother-of-pearl in a proportion ranging from 0.1% to 98% in the total mixture.

4. Use of a powder formed of mother-of-pearl and optionally aragonite according to claim 3, in which the powder is constituted such that the mixture contains ia mother-of-pearl in a proportion ranging from 5% to 20% in the total mixture. , and preferably 10% in the total mixture.

5. Use of a powder formed of mother-of-pearl and optionally aragonite according to claim 2, in finely pulverulent form and mixed with suitable excipients, with a view to its application in a culture of keratinocytes.

6 Use of a powder formed of mother-of-pearl and optionally aragonite according to claim 1, in finely pulverulent form and mixed with suitable excipients, for the production of pharmaceutical compositions ensuring the improvement of the qualities of the skin.

7 Use of a powder formed of mother-of-pearl and optionally aragonite according to claims 1 and 6, for the production of compositions pharmaceuticals ensuring the processes of restoring the structure of the skin.

8. Use of a powder formed of mother-of-pearl and optionally aragonite according to claims 1 and 6, for the production of pharmaceutical compositions exerting a protective role on the skin, and giving it active resistance under aggressive external conditions.

9. Use of a powder formed of mother-of-pearl and optionally aragonite according to claim 1, in finely pulverulent form and mixed with suitable excipients, for the production of cosmetic compositions ensuring the improvement of the appearance of the skin. .

10. Use of a powder formed of mother-of-pearl and optionally of aragonite according to claims 1 and 9, for the production of cosmetic compositions ensuring the improvement of the mechanical properties of the skin.

11. Use of a powder formed of mother-of-pearl and optionally aragonite according to at least one of claims 1, 6 and 9, with a view to producing compositions which give a young and dynamic appearance to the skin, thanks to a structure neoformed on the surface.

12. Pharmaceutical and / or cosmetic compositions ensuring the improvement of the qualities and appearance of the skin, characterized in that they consist of mother-of-pearl, optionally added with aragonite, in combination or in mixture with an excipient or a inert thinner, non-toxic, powdery.