Patent Application
20050100534
Subject of the invention is the use of one or more chemical compounds selected from the compounds of formulas Ia (firoin) and Ib (firoin-A) in cosmetic and dermatological formulations. The invention, for example, relates to the manufacture of a cosmetic or dermatological formulation for the protection and stabilization of human skin cells as well as their organic constituents such as, for example, proteins, enzymes, membranes, nucleic acids or antioxidants.
The invention embraces the use of physiologically compatible salts of the Ia and Ib compounds, the stereoisomeric forms of the compounds of formulas Ia and Ib and derivatives of these compounds (e.g. esters) for the use in cosmetic and dermatological formulations.
Since they originate from extremophilic microorganisms that by producing novel compatible solutes such as firoin und firoin-A protect themselves effectively against environmentally induced stress factors as UV radiation, heat, radicals, cold, dryness or osmotic or chemical stresses and, only in this way, are capable of surviving, these substances stand for a completely new approach to the protection of organisms and their components from harmful environmental influences.
The cell's inherent repair mechanism (DNA repair after UV damage, induction and stabilization of the chaperon proteins to newly form (partially) denaturized proteins and enzymes) can, for the first time, be stabilized and activated for the first time by firoin (β-mannosylglycerate) and firoin-A (β-mannosylglyceramide). Firoins, for the first time, enable the antioxidative potential of the cell (protein and DNA damage through free radicals, lipid oxidation of the cell membranes) to be maintained.
Due to their low molecular weight firoins penetrating through several skin layers enter the interior of the target cell and—acting as co-solvents or penetration intensifiers—are thus capable of carrying along other agents of cosmetic formulations (e.g. proteins, enzymes, vitamins, antioxidants) bringing them to the desired destination.
As a result of their chemical structure firoins are compatible with the majority of the customary cosmetic basic formulations and further adjustments to the desired and suitable form of application can be achieved by appropriately modifying the functional side chains. In this process and due to numerous hydroxy groups firoins feature moisturizing properties and are very pleasant to the skin.
Compatible solutes act as natural solvents in extremophilic microorganisms and stabilize enzymes, proteins and other cell constituents by generating a more native, globular state that not only protects proteins against proteolysis but moreover keeps them in a more compact and active condition. As co-solvents or penetration intensifiers for cosmetic agents firoins can be beneficially and broadly used for various applications particularly in view of a possible derivatization of individual functional groups.
Subject of the invention is thus the use of firoin and firoin-A as additives and agents offering a completely novel functioning principle in cosmetic and dermatological preparations and products.
Sunscreens
Today's skin and sun-protective agents comprise two classes of UV blocking filters. Physically active UV blocking filters consist of inorganic compounds (e.g. titanium dioxide) that reflect the light rays before hitting the skin's surface. Chemically acting organic molecules absorb the UV radiation of such wave lengths as are responsible for the formation of erythema (sunburn) (primarily between 295 and 323 nm with a maximum at 308 nm).
For that reason, all previous sunscreen preparations must be seen as mere “sunburn diminishers” that only guard against or prevent the dramatic effect of skin damage easily evident to the human eye. However, it has already been reported in literature that the even more dangerous damage to the cell caused well before the development of erythema may involve massive DNA damage that may even give rise to the formation of melanoma.
Protection Against Oxidative Stress, Radicals and Environmental Chemicals
In the field of cosmetics a multitude of free radical scavengers and antioxidants has been employed as additives of cosmetic preparations to protect against oxidative stress caused by environmental influences (UV radiation, smoke, chemical substances) as well as by cell-inherent activities. The broad range of agents embraces not only water-soluble free radical scavengers (e.g. ascorbic acid) acting in the liquid inner cell but also fat-soluble antioxidants (e.g. Retionol palmitate or cc-tocopherol) that have an effect on the membrane structures. In this context it is rarely mentioned that when these agents are applied topically not more than 3% of them reach deeper skin layers while the rest remains on the skin surface without having any effect.
Co-Solvents
Offering protection against harmful environmental influences human skin consists of several layers (stratum corneum, subdermis, dermis, epidermis) forming a barrier practically impenetrable to foreign substances. Potential routes of penetration open to cosmetic agents are intercellular (only for small polar and non-polar substances by lateral diffusion through the highly organized intercellular lipid layers), intracellular or transfollicular (liposome technology). There is evidence, however, that even when employing the innovative liposome encapsulation in nano-particles cosmetic agents are only capable of penetrating the upper skin layers at an extremely low percentage (<3%) to reach their targeted location where they are intended to take beneficial effect. Larger molecules such as enzymes promising in terms of potential effectiveness (e.g sericin, kollytin, glutathion-S-transferase or the groups of cytokines) can be introduced into living cells to a minute extent only due to steric hindrance, even by applying the most modern methods available.
Compatible Solutes and Hyperthermophiles
Hyperthermophiles are rather extraordinary microorganisms because they grow optimally at temperatures (60-110° C.) that in the event of mesophilic (,,normal”) organisms would lead to an extensive damage of cellular structures. In recent years comprehensive research efforts have been made to identify the biochemical components that bring about the remarkable thermal, chemical and physical stabilization of the cell structures. The focus of the research work in this context was on the isolation of thermally stable enzymes due to the fact that numerous enzymatically catalyzed industrial processes are carried out in extreme environments and suitable biocatalysts are required for these applications.
Although many enzymes from hyperthermophilic microorganisms are stable even under elevated temperatures this cannot be generally said of the cellular structures of thermophilic and hyperthermophilic organisms. The high temperature stability of cell structures is—to a remarkable extent—due to low-molecular organic substances (compatible solutes, ,,hypersolutes”) present in the intracellular environment. In recent years various new hypersolutes could be identified in hyperthermophilic microorganisms for the first time. In some cases it could be clearly shown that these compounds effectively contributed to the protection of cellular structures—first of all enzymes—against heat and dryness. bitop has developed technological solutions for the production of solutes from thermophilic microorganisms.
As interface and surface of the human body the skin is exposed to numerous external stresses. The human skin is an organ that consists of different, specialized cell types—the keratinozytes, melanozytes, Langerhans cells, Merkel cells as well as embedded sensory cells—and protects the body against external influences. In this context a distinction must be made between external physical, chemical and biological factors affecting the human skin. External physical influences are, inter alia, thermal and mechanical influences as well as the effects of radiation such as, for example, UV, VIS and IR radiation. External chemical influences particularly involve, inter alia, the effects of toxins, allergens and substances that attach to desoxyribonucleic acid. External biological influences mean the effects caused by foreign organisms and their metabolic products.
An excessive sun radiation leads to both acute skin damage such as for example sunburns and chronic changes such as, for example, skin aging or skin cancer. Sunburns (erythema solare) primarily develop when the skin is exposed to UV-B radiation. On the other hand, UV-A radiation by comparison has only a minor effect on the occurrence of sunburns. Sunburns of varying degree may develop ranging from a slight reddening to severe burns with blisters. Since these consequences will occur 4-6 h after exposure to radiation at the earliest, it will be too late to take countermeasures. Several sunburns—especially suffered during childhood—will increase the risk of skin cancer significantly. This is due to damage caused particularly to the nucleic acids of human skin cells and a faulty repair of the damaged desoxyribonucleic acid within the nucleus as well as possibly the immunosuppressive effect of UV radiation, i.e. a diminishing of the immune reaction as a result of the exposure to UV rays. An excessive exposure to UV-A and UV-B rays will increase the risk of a premature aging or light aging of the skin, for example in the form of structural changes of the connective tissue (actinic elastosis). An excessive exposure to UV-B rays is viewed as the main cause of chronic skin changes.
Due to changed recreational activities as, for instance, prolonged sunbathing or long-distance holidays in countries where the sun radiation is strong, dangers associated with skin cell damage due to UV exposure have increased severely in recent years which in turn entails a higher skin cancer risk. Moreover, the skin cancer risk has considerably increased lately as a result of the higher UV radiation present on the earth's surface on account of the stratospheric ozone depletion and also the higher live expectancy of mankind.
Aside from the still very topical problem of the lasting damage caused to cells due to UV radiation which by the use of customary sunscreens has hitherto been resolved only inadequately, the long underestimated influence of IR radiation damaging the skin cells thermally (thermal stress denaturizes cell proteins and enzymes) is being the subject of current discussions in research cycles. In the cosmetics industry no agents are known that offer protection against cell stresses caused by elevated temperatures.
Every tissue has an antioxidative potential (AOP) stemming from enzymatic and non-enzymatic antioxidants that in the unstressed cells keep the content of pro-oxidants below a limit that does not mean harm to the healthy cell. In the event these natural antioxidants become deactivated or denaturized the resistance as well as regenerative properties of the skin will decrease significantly.
Hitherto only a few natural substances have been known in preventive cosmetics and dermatology that actively promote the cell-inherent repair mechanisms of the cell and in this manner safeguard the cell “from within” (in vivo) against, for example, elevated UV radiation, IR radiation, heat, free radicals, cold, dryness, osmotic stress or chemical stress. Therefore, the objective was to provide cosmetic and dermatological formulations whose application eliminates or at least alleviates the above described skin problems and which, in particular, are suited to protect and stabilize human skin cells and their organic components.
It is thus a general problem of cosmetics and dermatology that there are no clearly chemically defined and harmless agents and additives of natural origin available to satisfactorily resolve the above mentioned important objectives within the fields of application indicated. The present invention proposes a solution of this problem.
Extremophilic microorganisms (thermophiles and hyperthermophiles) protect themselves against thermal stress by the formation of firoin and firoin-A. In the presence of these substances these microbial living organisms are capable of existing under extreme environmental conditions because firoin and firoin-A serve to stabilize and protect the metabolism and the essential organic components against damage.
Surprisingly, it has now been ascertained that firoin and firoin-A also exhibit their stabilizing effects when applied to the human skin and thus must be seen as ideal agents and additives for cosmetic and dermatological preparations. Firoin und firoin-A thus represent a universally applicable and completely novel protective principle in the field of cosmetics and dermatology. Therefore, according to the invention the above mentioned problem can be resolved by making use of one or more chemical compounds selected from the compounds of formulas Ia (firoin) and Ib (firoin-A) in cosmetic and dermatological formulations. The invention relates to the use of one or more compounds selected from the compounds of formulas Ia (firoin) and Ib (firoin-A),
the physiologically compatible salts of compounds Ia and Ib, the stereoisomeric forms of the compounds of formulas Ia and Ib as well as of derivatives for the production of a cosmetic or dermatological formulation aimed at the protection and stabilization of human skin cells and their organic constituents such as, for example, proteins, enzymes, membranes, nucleic acids or antioxidants. As salts of compound Ia the alkaline and alkaline-earth salts are suited, in particular the Na and the K salt. As derivatives of compound Ia their esters with physiologically compatible alcohols, especially the C1-C4 alcohols, are considered suitable.
The invention relates, in particular, to the use of one or more compounds selected from the compounds of formulas Ia and b, the physiologically compatible salts of the compounds of formulas Ia and Ib and the stereoisomeric forms of the compounds of formulas Ia and Ib for the production of a cosmetic or dermatological formulation aimed at the protection and stabilization of human skin cells and their organic constituents such as, for example, proteins, enzymes, membranes, nucleic acids, antioxidants etc. to guard against physical, chemical and biological influences such as radiation (UV, IR, VIS rays), denaturizing substances, temperature or cold.
The present invention describes this protective principle for the first time. Possible fields of application are versatile and can only be described by way of examples within the framework of the invention. However, the invention shall not be limited in whatever way by giving or describing such examples.
Firoin of very high concentration is present as compatible solute in microorganisms. For example, the intracellular concentration in P. furiosus comes to 250 mM=67 g/l. As a result of these findings and in all application investigations carried out so far the compound has proved to be fully compatible with biological structures. These characteristics alone must be considered an ideal prerequisite for the use of firoin as cosmetic and dermatological agent.
Firoins show structural motives of classical stabilizers (OH groups of mannose, glycerine, amino function) and thus ideally combine two important stabilization mechanisms: stabilization of OH groups (e.g. trehalose, saccharose, hydroxyectoine) and preferential exclusion (e.g. ectoine):
Furthermore, firoin has the following properties:
Finally, the solubilizing effect of firoin substituting the water inside the cell must not be forgotten. Same as the other compatible solutes firoin is to be seen as the natural solvent of the cell. To actually take effect within the cell biogenic substances have to be solubilized.
Further chemical properties of firoins have been summarized and shown in the following table.
Firoin for the Stabilization of Liposomes and Membranes
Liposomes gain more and more importance as skin-penetrating vehicles, e.g. also for agents not solely used in the field of cosmetics. Liposomes are artificial lipid bilayers—artificial membranes—whose stability is limited, however, so that there is a need for stabilizing liposome preparations to withstand, for example, temperature and osmotic stresses and enhance their storage and transportation properties. This is the only way to make sure agents are effectively applied via liposomes.
Membranes constitute the natural barriers of cells and cell organellae at the surrounding medium. It is the membranes that make sure a constant inner environment prevails within the individual cells and cell constituents. Biological membranes are multi-component systems. The exact composition of individual membranes varies to a greater or lesser extent depending the origin of the membranes. However, lipids and proteins are elementary constituents of membranes.
Lipids can be subdivided into so-called ,,simple” lipids such as fats and waxes and “complex” lipids. Aside from phospholipids derived from sn-glycerine-3-phosphoric acid phosphate-free lipids such as glycolipids are present in the cell. Glycolipids contain covalently bonded carbohydrate residues. The carbohydrates are glycosidically attached to the primary hydroxygroup of the alcohol component. Apart from the glycoproteins glycolipids play an important role in the interaction between the cells proper and with biologically active molecules (e.g. as part of receptors).
A multitude of glycolipids is present in the membranes in the form of glyceroglycolipids. These compounds are characterized by a gycerine residue being glycosidically linked with a carbohydrate residue. An example of a group of these compounds is shown in the following figure in which a mannose residue represents the carbohydrate residue of the lipid. The organic residues R1 and R2 are usually fatty acids, carbohydrates or sulfonic acid groups esterified with the alcohol groups of the gycerine residue.
The compatible solute firoin represents the condensation product of mannose and gycerine acid. A comparison of the structure of this compound with that of the above mentioned glycolipids indicates a significant structural analogy between both components.
This structural analogy to the membrane-forming glycolipids of cells and cell organellae and the experimentally proved protective potential as a guard against osmotic stress and protein stabilizer makes firoin an ideal stabilizing substance for liposome preparations, membranes, membrane proteins or microemulsions. The growing importance of microemulsions in the cosmetics industry has, for example, been described by Schwuger and Stickdorn (1998).
Cosmetically relevant fields of application for firoin are, inter alia:
In addition to the above described application possibilities firoin also performs a moisture regulating function for the skin. Due to the presence of numerous hydroxygroups within the molecule and high stability firoin is especially suitable as heat resistant moisture regulator with depot effect. This has particular significance for the regulation and balancing of the skin's moisture characteristics.
Finally, the solubilizing effect of firoin substituting the water inside the cell must not be forgotten. Same as the other compatible solutes firoin is to be seen as the natural solvent of the cell. To actually take effect within the cell biogenic substances have to be solubilized.
Desiccation/dehydration processes impair and damage skin constituents irreversibly in that cells, membranes and proteins are destroyed. Both the resistance and the regenerative capability of the skin diminish. Furthermore, skin aging processes accelerate in the end. Basically, the desiccation process the skin is subjected to is identical to a freeze-drying process, only the pertinent stress conditions are much more severe. Based on the protective potential of firoin in the area of freeze drying it can thus be plausibly deducted that firoin in conjunction with drying processes may act not only as a moisturizing agent but also as an actively functioning protective substance.
Using the invention in trade and industry encompasses the entire field of cosmetic and dermatological products as well as its application as research reagents in cosmetic and dermatological development work. Moreover, an application in trade and industry also involves the post-operative treatment of the skin (e.g. tending wounds in order to promote healing processes) and the addition of the compounds to plasters, masks and bandages as they are applied to the skin.
Further conceivable applications of compound Ia in cosmetic and dermatological fields are, for example:
The cosmetic and dermatological formulations are manufactured in that one or several compounds of formulas Ia and Ib (firoin and/or firoin-A), the physiologically compatible salts of compounds of formulas Ia and Ib, the stereoisomeric forms of the compounds of formulas Ia and Ib or derivatives, if expedient with the aid of auxiliary and/or carrier substances, are appropriately dealt with so as to bring about a suitable formulation.
The auxiliary and carrier substances stem from the group of carrier agents, preservative agents and other customary auxiliary agents. The compounds of formulas Ia and Ib (firoin and/or firoin-A), the physiologically compatible salts of the compounds of formulas Ia and Ib and the stereoisomeric forms of the compounds of formulas Ia and Ib as contained in cosmetic and dermatological formulations are for external application. They may for example be used in the form of solutions, suspensions, emulsions, pastes, ointments, gels, creams, lotions, powder, soaps, surfactant-containing cleaning preparations, oils and sprays. Moreover, customary carrier substances, auxiliary substances of any kind and, if thought expedient, further agents may be added to the formulations. Preferable auxiliary substances stem from the group of preservative agents, antioxidants, stabilizers, solutizers, vitamins, coloring agents and de-odorizers.
Aside from one or several compounds selected from the compounds of formulas Ia and Ib ointments, pastes, creams and gels may contain the customary carrier substances such as, for example, animal and vegetable fats, waxes, paraffins, starch, traganth, cellulose derivatives, polyethylene glycols, silicones, bentonites, silicic acid, talcum and zinc oxide or mixtures/blends of these substances.
Aside from one or several compounds selected from the compounds of formulas Ia and Ib powders and sprays may contain in addition to the customary carrier substances the customary propellants, e.g. chlorofluorohydrocarbons, propane/butane or dimethyl ether.
Aside from one or several compounds selected from the compounds of formulas Ia and Ib solutions and emulsions may additionally contain the customary carrier substances such as solvents, solutizers and emulgators or oils.
Aside from one or several compounds selected from the compounds of formulas Ia and Ib suspensions may contain additional carrier substances such as, for example, water or ethanol.
Further forms of application are, for instance, soaps, surfactant-containing cleansing agents, face and body oils, lipsticks, lip-care sticks, mascara, eyeliners, eye shadowing, rouge, powder, emulsion and wax make-up, as well as sunscreen, pre-sun and after-sun preparations.
The proportion of the compounds of formulas Ia (firoin) and Ib (Firoin-A), the physiologically compatible salts of the compounds Ia and IB and the stereoisomeric forms of the compounds of formulas Ia and Ib in cosmetic and dermatological formulations preferably amounts to 0.0001 to 50% by weight, especially preferred is 0.001 to 10% by weight based on the entire cosmetic formulation.
The cell-inherent antioxidative potential is promoted by the application of firoins, for example, through their proven stabilizing effect to prevent thermal protein denaturation and deactivation. In this way, an impairment as a result of free radicals is counteracted. As a result of the proven DNA protection of compatible solutes and their protein stabilizing effect the application of firoins according to the invention is to be regarded as a novel type of active sun protection (e.g. UV and IR radiation) in cosmetics and dermatology.
The following examples are meant to provide elucidation on the present invention but shall by no means limit its scope.
According to the invention a firoin-containing lotion (O/W) is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
According to the invention a firoin-containing cream (O/W) is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
According to the invention a liposome-containing gel that contains firoin is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
According to the invention a firoin-containing gel (O/W) is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
According to the invention a firoin-containing sunscreen emulsion is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
According to the invention an emulgator-free firoin-containing sunscreen lotion SPF 30 (O/W) is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
According to the invention a firoin-containing hair tonic is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
According to the invention a firoin-containing spray formulation is made from the following components:
As preservative agent 0.05% propylhydroxybenzoate or 0.15% methyl-4-hydroxybenzoate may be used.
| Number | Date | Country | Kind |
|---|---|---|---|
| 100 40 933.4 | Aug 2000 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP01/09445 | 8/16/2001 | WO |
