AU2003264697B2 - Cosmetic composition for fighting against skin ageing - Google Patents

Abstract

The invention concerns a cosmetic composition containing a Diospyros kaki extract and a Pueraria lobata extract. The invention also concerns the use of said composition for preventing and/or for fighting against skin ageing.

Description

Dec 18 04 10:17a ICR Translations 2159221789 p.

2 For: COSMETIC COMPOSITION CAPABLE OF FIGHTING AGAINST SKIN AGING VERIFICATION OF TRANSLATION Arthur C. Haines, residing at 614 South 8' Street, Philadelphia, PA 19147, declares: that he knows well both the French and English languages; that he translated the above-identified Application from French to English; that the attached English translation is a true and correct translation of the aboveidentified Application to the best of his knowledge and belief; and that all statements made of his own knowledge are true and that all statements made of information and belief are believed to be true, and further that these statements are made with the knowledge that willful false statements and the like may jeopardize the validity of the Application or any patent issuing thereon.

Date:)tC-ev' a Lr\ 2.00 Han Name: Arthur C. Haines -PHILl:36!7076,vI WO 2004/004680 PCT/FR2003/002124

I

COSMETIC COMPOSITION CAPABLE OF FIGHTING AGAINST SKIN AGING The present invention pertains to a new cosmetic composition capable of fighting against skin aging containing two plant extracts: Diospyros kaki and Pueraria lobata.

The term "cosmetic composition capable of fighting against skin aging" is understood to mean any cosmetic composition capable of preventing or limiting the consequences of chronological and/or actinic aging at the level of the cutaneous collagen and consequently to prevent or limit the cutaneous appearance of visible signs of aging on the skin surface: wrinkles and lines.

Skin aging is characterized among other factors by a global decrease in the thickness of the skin (loss of 6% every ten years starting at birth), a decrease in cell renewal and a decrease in collagen at the level of the dermis associated with an increase in the glycation of the cutaneous proteins.

For women, there is added to this chronological process an aging which can be characterized as hormonal aging subsequent to the drop in the production of estrogens at menopause. This deficiency in estrogens affects the fibroblasts at the dermal level and consequently all of the components of the extracellular matrix, collagen in particular.

Nonenzymatic glycation of proteins represents the first cause of modification of the cutaneous collagen. Different types of collagen exist and represent 70 to 80% of the dry weight of the dermis. These collagens are constituted by a characteristic triple helix and are organized in fibers.

Enzyme-dependent natural couplings normally stabilize the collagen fibrils.

But the glycation phenomenon itself can be responsible for another type of coupling due to a nonenzymatic fixation of the glucose. The collagen fibers then become more rigid, more resistant to pressure and more resistant to collagenases; the renewal of the collagen no longer takes place, the tissues WO 2004/004680 PCT/FR2003/002124 2 are altered, rigid and fragile. This becomes an issue of a true process of reticulation with the creation of abnormal and irreversible cross-links. This reticulation is one of the major expressions of skin aging.

The glycated collagens coupled in this manner lose their biological functionality; the tissues become rigid and sclerotic. Glycation is dependent on the possibilities of contact between the circulating glucose molecules and the free amine groups existing either at the N-terminal ends of polypeptide chains or on the lateral lysine chains.

The biochemical mechanism of this reaction is well known and comprises two phases: 1. An early phase (initiation): reaction of reducing sugars (glucose, fructose) with the terminal or lateral amine functional groups of the constitutive proteins of the tissues so as to produce compounds called Schiff bases.

These compounds are subsequently stabilized by Amadori rearrangement into ketoamine.

2. A late phase (propagation and termination): the ketoamine functional groups are oxidized into deoxysone in the presence of oxygen and reaction with other basic amino acids such as arginine and lysine belonging to the other proteins (albumin, lipoproteins, immunoglobulins). The result is the formation of complexes with final couplings of the type of pentosidine rings or 6,3-furoyl-1,4-furanyl-imidazole.

One of the important consequences of the glycation of proteins is the creation of free radicals. In effect, when proteins are glycated, they react with oxygen and cause the formation of superoxide type radical groups. These radical groups are capable of initiating the degradation of proteins, of altering membrane structures and finally disorganizing the extracellular matrix as well as all of its components.

The cutaneous collagen, as well as all of the other components of the extracellular matrix, is also affected by the decrease in estrogens during WO 2004/004680 PCT/FR2003/002124 3 menopause. In fact, the drop in the estrogen levels causes a decrease in the synthesis of collagen by the fibroblasts as well as an increase in its degradation. This collapse occurs quickly and can reach 30% in the first five years of menopause. The production of finer type III fibers contributes to the annual loss of 1% of dermal thickness. Finally, there is also a deterioration in the structural glycoproteins which has the consequence of disturbing the three-dimensional organization of the extracellular matrix.

A cosmetic composition useful for fighting against skin aging must therefore contain active ingredients capable of restraining the glycation of proteins and compensating for the estrogen deficit. In this manner, the collagen would be protected; collagen is the major molecule of the skin and confers on the skin its mechanical properties. The appearance of wrinkles and the decrease in the cutaneous tonicity are the reflection of the aging of the dermis and notably the aging of its mechanical properties (quantitative diminishment of the collagen network as well as its rigidification).

The applicant's research has demonstrated that the combination of two plant extracts Diospyros kaki and Pueraria lobata presents a protective action on the cutaneous collagen, respectively an anti-glycation activity and a hormone-like activity, which make these two extracts a useful composition for fighting against skin aging.

The invention pertains most particularly to a composition containing an extract of Diospyros kaki and an extract of Pueraria lobata.

Diospyros kaki, also called Japanese or Oriental persimmon, is a tree originating from hot regions, principally Indonesia. It can be grown in the same regions where olive and fig trees thrive. After the falling of the deciduous leaves, there can be seen yellow fruits that subsequently turn orange. Local patterns of use have demonstrated the properties of different parts of the tree: the bark of the stems is astringent; the fruit is used in WO 2004/004680 PCTIFR20031002124 4 traditional medicine for its antitussive, laxative and nutritive properties; the fresh fruit juice is used against hypertension.

The cosmetic composition which is the object of the present invention contains an extract of Diospyros kaki.

This extract is advantageously obtained from the calyxes of Diospyros kaki. The extract is preferably water soluble and, more particularly, it is a hydroglycolic extract. This extract is advantageously obtained according to the following protocol: the Diospyros kaki calyxes are dissolved in butylene glycol, (ii) the soluble and insoluble phases are separating by filtration, (iii) sterilizing filtration.

The water-soluble, and more particularly hydroglycolic, extract of Diospyros kaki used in the composition according to the invention has a clear liquid appearance, an amber color and a characteristic odor. It presents the following analytical characteristics: dry matter 9-16 g/l.

total polyphenols 2-4 g/I (flavanol, hydroxycinnamic acid, protocatechuic acid and abscissic acid).

pH 5-6.

Pueraria lobata, also called kudzu, is a woody vine or liana of the legume family, originating from southern and tropical Asia. This plant bears very fragrant flowers flowing in long clusters and producing brown pods containing 3 to 10 seeds with thick integuments. Its roots are thick or tuberous, its alternating leaves are covered by a very dense brown down. Pueraria lobata contains natural molecules which have an activity similar to that of estrogens.

These nonsteroidal substances are isoflavones such as genisteine, daidzeine, coumestrol and pratensein.

The cosmetic composition which is the object of the present invention contains an extract of Pueraria lobata, advantageously obtained from the WO 2004/004680 PCTIFR200310021 24 roots of the plant. This extract is preferably water soluble and, more particularly, hydroglycolic. This extract is advantageously obtained according to the following protocol: grinding to 2 mm, 1 weight unit, addition of ethanol, 5 volume units, extraction at reflux for 4 hours, filtration-concentration-evaporation to dryness then addition of glycerinwater, filtration at 0.2 pm.

The water soluble, more particularly hydroglycolic, extract of Pueraria lobata used in the composition according to the invention has a clear liquid appearance of an orangish yellow color and a characteristic odor. It presents the following analytical characteristics: Refraction index (at 25°C) 1.385-1.405.

Density (at 20°C) 1.0-1.2.

Isoflavone content (HPLC) 0.3-0.6%.

pH 4.5-6.5.

The composition according to the invention contains: on the order of 0.1 to 10% by weight, preferably 0.5 to 5% by weight, of Diospyros kaki extract and on the order of 0.1 to 10% by weight, preferably 0.5 to 5% by weight, of Pueraria lobata extract.

The composition which is the object of the present invention can also contain any plant extracts rich in flavonoids and/or tannins. In fact, the flavonoids interact with the collagen fibers and very effectively protect them from the proteolytic degradation present upon skin aging. Moreover, the rich content of tannins of the plant extracts confer stimulating, antioxidant and protective activities. An antioxidant activity is particularly useful for fighting against skin aging. As a nonexhaustive example of a tannin-rich plant extract WO 2004/004680 PCT/FR2003002124 6 that can be used in the framework of the present invention we can cite an extract of wild teasel (Dipsacus sylvestris). Wild teasel, also called wolfs comb and Venus' basin, is a biannual herbaceous plant of 60 to 150 cm that it is found everywhere in Europe along roads and ditches.

The extract of wild teasel that can be used in the framework of the invention is, more particularly, obtained by digestion in a hydroglycolic mixture from the finely ground aerial parts of the plant; it is then decolored, clarified, standardized and stored.

The plant extracts rich in flavonoids that can be used are advantageously selected from the group constituted by an extract of rosemary (Rosmarinus officinalis), an extract of galangal (Alpina officinarum) and an extract of buddleia (Buddleia davidii).

An extract of rosemary (Rosmarinus officinalis) that can be used in the framework of the invention is advantageously a water-soluble extract obtained from the leaves of this common plant of the Mediterranean region. This extract contains flavonoids, ursolic acid and rosmarinic acid. The extract is obtained according to the method described in the French patent application published as number FR 9815394.

Galangal (Alpina officinarum) from the ginger family is a shrub originating from East Asia. Its black, gnarled rhizome resembles that of ginger. The galangal extract that can be used in the composition of the invention is a water-soluble extraction of galangal rhizomes obtained by controlled extraction by a water/propylene glycol mixture followed by a centrifugation/filtration step. This galangal extract is rich in phytosterols and flavonoids (1.5 g/l rutin equivalent) such as galangin and kaemferol and in essential oils such as bomeol, cineol, caryophylene and geraniol.

The extract of buddleia (Buddleia davidii) that can be used in the framework of the present invention is advantageously a water-soluble extract of buddleia obtained from the dried plants and more particularly from the dried WO 20041004680 PCT/FR2003/002124 7 flowers and leaves. The dried flowers and leaves are ground then an ethanol/water extraction is performed. The resultant extract is concentrated after a filtration step and, optionally, a formulation step in glycerin. The watersoluble extract of buddleia that can be used in the composition of the invention contains iridoids, flavonoids (antioxidant agents), esters of caffeic acid (antioxidant agents) and triterpenoids.

The compositions according to the invention can also comprise one or more formulation agents or additives of known and conventional use in cosmetic and dermatological compositions such as, in the form of nonlimitative examples, softeners, coloring agents, film-forming agents, surface-active agents, perfumes, preservatives, emulsifiers, oils, glycols, vitamins such as vitamin B, UV filters, etc. Based on his knowledge of cosmetics, the expert in the field would know which formulation agents to add to the compositions of the invention and in what amounts in relation to the desired properties.

It should be noted that the addition of UV filters to the cosmetic composition according to the invention enables fighting against the actinic aging induced by UV radiation. The UV filters that can be used in the cosmetic composition according to the invention can be chemical or mineral filters. The UV filters that can be used in the cosmetic composition according to the invention are advantageously the filters described in the French patent application published as number FR 2811224.

The compositions according to the invention can be presented in any form known by the expert in the field of cosmetology and dermatology without other pharmaceutical restriction than that of application on the face and on the body. The compositions according to the invention are advantageously presented in the form of a gel, lotion, cream, emulsion, milk, spray, etc.

The present invention also pertains to the use of a composition according to the invention for preventing skin aging and/or for fighting against it.

WO 2004/004680 PCTIFR2003/0021 24 8 The present invention also pertains to the use of extracts of Diospyros kaki and of Pueraria lobata for the preparation of a cosmetic or dermatological composition for preventing skin aging and/or fighting against it.

Other advantages and characteristics of the invention will become apparent from the examples below which pertain to the effect of the extract of Diospyros kaki and of Pueraria Iobata on the cutaneous collagen and the examples of formulation which are presented for illustrative purposes and should not be interpreted as limiting the scope of the invention.

I. Effect of the extract of Diospyros kaki on the glycation of proteins The effect of the extract of Diospyros kaki was studied in vitro on a model based on the measurement of the formation of the derivatives of the glycation reaction between lysine and glucose 6-phosphate. Certain of these derivatives (AGE) are fluorescent. The reaction was measured after 15 days of incubation.

Operating mode: A reference molecule was tested in parallel: aminoguanidine.

Test system: The test system is the reaction mixture containing bovine albumin g/ml) and glucose (500 mM) in a phosphate buffer (0.2 M, pH Incubation products test system: The products were mixed with the test system in sterile tubes; the tubes were covered with aluminum foil (the reaction must take place shielded from light).

For the experimental conditions in which certain reagents or products are not present, the volume of the QSP tube should be completed with MilliQ water.

WO 20041004680 PCT/FR2003/002124 9 After having sealed the openings of the tubes with parafilm (the reaction must take place without oxygen), the different reaction media were placed in a dry oven at 370C for 8 days.

Evaluation of the effects: After 8 days of incubation, 100 pl was collected from each tube and transferred to a 96-well black plate.

The fluorescence was then read using FLUOstar (BMG) (excitation at 355 nm, emission at 460 nm). The results are expressed in arbitrary fluorescence units.

The relative fluorescence for the "product bovine albumin" interference) is to be subtracted from the "product bovine albumin glucose" data.

Results: After 8 days of incubation of bovine albumin with an overcharge of glucose, the formation of glycation cross-linking was seen. It was evaluated by taking advantage of the fluorescence properties of the bovine albuminglucose adduct.

The kaki extract present in the test system prevented the cross-linking between the bovine albumin and the glucose in a quite effective manner (see table I below).

Table 1. An-glycation activity of the Diosp TUS kaki extract.

Product Intensity of Interference Intensity of real inhibition of the fluorescence (without glucose) fluorescence glycation (arbitrary units) (arbitrary units) (arbitrary units) Control 50,229.5 291 49,938.5 1 (BSA glucose) Aminoguanidine 13,011.5 17,537 0 100

MM)

Diospyroskaki 34,131.5 21,093.5 13,038 73.9 Diospyros kaki 34,282 24,883 9,399 81.2 1% Diospyros kaki 9,869 33,893 5,976 88.0 3%11 Diospyros kaki 43,052.5 37,550.5 5,502 89.0 WO 2004/004680 PCTIFR0030021 24 II. Effect of the extract of Pueraria lobata on the synthesis of proteins The effect of the extract of Pueraria lobata was studied in vitro on fibroblast cultures: measurement of the stimulation of the cell metabolism and the synthesis of proteins.

Principle: Normal human fibroblasts were cultured in a conventional DMEM medium supplemented with fetal calf serum in the presence of Pueraria lobata extract.

After an optimal period of incubation, the total quantity of intracellular and extracellular proteins was determined according to the BCA method. The cell metabolism was quantified by the MTT method which indicates the level of mitochondrial respiration.

Results: The Pueraria lobata extract stimulated the metabolism and synthesis of proteins in a dose-dependent manner.

The MTT values (mitochondrial cellular respiration) and quantity of proteins per 1000 cells were determined in parallel but independently on the same cell cultures. The Pueraria lobata extract at 0.3% augmented the MTT conversion by 44%. This increase in the MTT conversion reached 66% for the 1% extract of Pueraria lobata. For the same time, the total quantity of proteins synthesized by the cells reached 99%.

ll. Examples of formulations according to the invention Cream Emulsifiers 7.000 Triglycerides 10.000 Shea butter 2.000 Silicon oils 1.500 Neutralized gelling agent 0.600 Glycerin 5.000 Sequestration agent 0.100 Teasel extract 2.000 Buddleia extract 1.000 Rosemary extract 1.000 Kaki extract 3.000 WO 2004/004680 Pueraria extract Pequi oil Perfume Preservatives Purified water PCTIFR2003/002124 Gel Butylene glycol Neutralized thickening agent Sequestration agent Ethyl alcohol Kaki extract Pueraria extract Teasel extract Rosemary extract Solubilizer Perfume Preservatives Purified water 3.000 2.000 0.500 1.000 QSP 100 2.000 1.000 0.100 5.000 3.000 3.000 2.000 2.000 1.000 0.500 0.700 QSP 100 0.600 2.000 3.000 0.100 1.000 2.000 2.000 1.000 4.000 4.000 2.000 7.000 0.600 0.400 QSP 100 Serum Gelling agent Glycerin Butylene glycol Sequestration agent Rosemary extract Teasel extract Buddleia extract Galangal extract Kaki extract Pueraria extract Triglycerides Silicon oils Preservatives Perfumes Purified water

Claims (8)

1. Cosmetic composition, characterized in that it contains: an extract of Diospyros kaki and an extract of Pueraria lobata, and one or more formulation agents or additives of known and conventional usage in cosmetic and dermatological compositions.

2. Cosmetic composition according to claim 1, characterized in that the extract of Diospyros kaki is an extract derived from the calyxes of the plant and the total polyphenol concentration of which is from 2 to 4 g/l.

3. Cosmetic composition according to either claim 1 or 2, characterized in that the extract of Pueraria lobata is an extract derived from the roots of the plant and the total isoflavone content of which is from 0.3 to 0.6%.

4. Cosmetic composition according to any one of claims 1 to 3, characterized in that it contains: on the order of from 0.1 to 10% by weight, preferably 0.5 to 5% by weight, of Diospyros kaki extract and on the order of from 0.1 to 10% by weight, preferably 0.5 to 5% by weight, of Pueraria lobata extract.

Cosmetic composition according to any one of claims 1 to 4, characterized in that it moreover contains at least one active plant ingredient rich in flavonoids and/or in tannins selected from among the groups constituted by an extract of wild teasel (Dipsacus sylvestris), an extract of rosemary (Rosmarinus officinalis), an extract of galangal (Alpina officinarum) and an extract of buddleia (Buddleia davidi). 13

6. Cosmetic composition according to any one of the preceding claims characterized in that it moreover comprises one or more formulation agents or additives such as softeners, coloring agents, film-forming agents, surface-active agents, perfumes, preservatives, oils, glycols, vitamins and UV filters.

7. Use of a composition according to claims 1 to 6 to prevent skin aging and/or to fight against it.

8. Use of extracts of Diospyros kaki and of Pueraria lobata as defined according to any one of claims 1 to 4 for the preparation of a cosmetic or dermatological composition for preventing skin aging and/or fighting against it.