Essential oil of achillea as anti-ageing agent

Abstract

The present invention relates to the cosmetic use of an essential oil of Achillea, as an active agent for preventing and/or treating the signs of skin ageing, characterized in that this essential oil of Achillea comprises the following compounds, each present at more than 5% by weight relative to the total weight of the essential oil: artemisia ketone, chrysanthenone (two combined isomers), and ascaridole. It also relates to the associated cosmetic process.

Claims

1. Cosmetic method for preventing and/or treating the signs of skin ageing, comprising applying a composition to a subject in need thereof comprising from 0.05% to 0.8% by weight relative to the total weight of the cosmetic composition of an essential oil of Achillea, as an active agent, wherein this essential oil of Achillea comprises the following compounds, each present at more than 5% by weight relative of the total weight of the essential oil: artemisia ketone, chrysanthenone (two combined isomers), and ascaridole.

2. Cosmetic method according to claim 1, of an essential oil of Achillea also comprising the following compounds: para-cymene, 1,8-cineole and beta-phellandrene, and camphor.

3. Cosmetic method according to claim 1, of an essential oil of Achillea comprising the following compounds, each present at more than 6% by weight relative to the total weight of the essential oil: artemisia ketone, chrysanthenone (two combined isomers), and ascaridole.

4. Cosmetic method according to claim 1, of an essential oil, in which the following compounds are each present at concentrations of greater than 1% by weight relative to the total weight of the essential oil: camphene, yomogi alcohol, alpha-thujone, artemisyl acetate, and isoascaridole.

5. Cosmetic method according to claim 1, wherein the essential oil of Achillea is obtained from the aerial part of Achillea.

6. Cosmetic method according to claim 1, said signs of skin ageing being chosen from wrinkles and/or fine lines, dull and lifeless skin, thinning of the skin, loss of firmness and/or of elasticity and/or of tonicity and/or of suppleness of the skin and/or slackening of the skin.

7. Cosmetic method according to claim 1, said signs of skin ageing being induced by extrinsic ageing, or induced by chronological ageing.

8. Cosmetic method according to claim 1, in which said essential oil of Achillea is present in a cosmetic composition.

9. Cosmetic method according to claim 8, wherein said composition is intended for topical or oral administration.

10. Cosmetic method according to claim 8, in which the essential oil is formulated in an anti-ageing cream.

11. Cosmetic process for preventing and/or treating the signs of skin ageing, comprising at least one step of topical application to the skin of a composition comprising at least one essential oil of Achillea, as defined according to claim 1.

Description

EXAMPLES

Example 1: Production of an Essential Oil of Achillea

(1) An essential oil of Achillea was prepared by distillation of 300 g of fresh aerial part picked at the deblossomed stage, in an apparatus of Clevenger type, by dry distillation, for 1 h 30. An essential oil was obtained with a yield of about 0.25% to 0.50%. The essential oil thus obtained contains:

(2) TABLE-US-00001 Ascaridole 11.70% Artemisia ketone 33.4% Chrysanthenone 6.6% Camphene 1.2% Yomogi alcohol 1.3% Para-cymene 5.7% 1,8-Cineole and beta-phellandrene 6.3% Alpha-thujone 4.3% Camphor 5.3% Artemisyl acetate 1.3% Isoascaridole 1.0%

(3) The composition of the essential oil obtained was determined by GC and mass spectrometry.

Example 2: Effect of an Essential Oil of Achillea on Collagen IV Production by Primary Normal Human Keratinocytes

(4) The test which follows makes it possible to show that the essential oil of Achillea causes an increase in collagen IV production by primary normal human keratinocytes. This demonstration is carried out by in situ immunolabelling and image analysis.

(5) Procedure:

(6) The keratinocytes were seeded into and cultured in culture medium for 24 hours.

(7) The culture medium (2.5 ml) was then replaced: either with test medium containing TGF- (Transforming Growth Factor ) at 10 ng/ml (positive control), or with test medium containing the essential oil of Example 1 at 0.003% by volume, or with the same culture medium (control).

(8) The cells were then incubated for 72 hours at 37 C.

(9) The culture medium was removed and the cells were rinsed, fixed and permeabilized. They were then labelled with an Anti-Collagen IV primary antibody sold by Abcam (reference: Ab6586) directed against the protein of interest (collagen IV). This antibody was visualized with an Alexa Fluor 488 Goat Anti-Rabbit IgG (H+L) secondary antibody sold by Invitrogen (reference: A11008) coupled to a fluorochrome (GAR-Alexa 488). In parallel, the nuclei of the cells were stained with Hoechst 33258 (bisbenzimide).

(10) The image acquisition was carried out with an INCellAnalyzer1000 (GE Healthcare) high-resolution imaging system. For each well, 5 digitized images were acquired.

(11) The labellings were quantified by measuring the fluorescence intensity of the proteins relative to the number of nuclei identified by the Hoechst product (integration of the digital data using the Developer Toolbox 1.5 software, GE Healthcare).

(12) ResultsConclusion

(13) FIGS. 1 to 3 represent the fluorescence microscopy images obtained after collagen IV-immunolabelling of keratinocytes according to the protocol described above.

(14) FIG. 1 represents the collagen IV produced by the control keratinocytes.

(15) FIG. 2 represents the collagen IV produced by the keratinocytes treated with TGF- (tested at 10 ng/ml). This is the positive control of the experiment.

(16) FIG. 3 represents the collagen IV produced by the keratinocytes treated with the essential oil of Achillea (tested at 0.003%).

(17) TGF- (tested at 10 ng/ml) very strongly and significantly stimulated collagen IV production by the keratinocytes (594% relative to the control). This effect was expected and validates the test.

(18) Under the experimental conditions of this study, the essential oil of Achillea (tested at 0.003%) significantly stimulated collagen IV expression (171% relative to the control) by the keratinocytes.

(19) Thus, the essential oil of Achillea in accordance with the invention makes it possible to increase collagen IV production by keratinocytes and, consequently, to prevent and/or treat the signs of skin ageing.

Example 3: Effect of an Essential Oil of Achillea on Intra-Tissue Glutathione Concentration

(20) The present example aims to show that the essential oil of Achillea makes it possible to increase the intra-tissue glutathione concentration.

(21) For this, the GSH level was measured in the epidermis of a Realskin reconstructed skin which was: nontreated (control), treated with essential oil of Achillea at 0.01% by volume, or treated with lipoic acid at 250 mol.Math.l.sup.1 (positive control).

(22) Procedure:

(23) The reconstructed tissue model kits are conditioned for transport on agar medium. Upon arrival, the tissues were reconditioned in a maintenance medium for a minimum of 16 h at 37 C. in a moisture-saturated atmosphere enriched with 5% CO.sub.2. The same medium was used for the incubations in the presence of the substrate.

(24) The various solutions (2 ml) (of essential oil of Achillea at 0.01% by volume and of lipoic acid at 250 mmol.Math.l.sup.1) were deposited in the wells underneath the skins in order to diffuse through said skins more easily by capillary action. The tissues were then incubated in an incubator at 37 C. for 16 h.

(25) The tissues were ground by means of a Potter grinder in 250 ml of a solution of N-ethylmaleimide (NEM) at 2.5 mmol.Math.l.sup.1 (excess of NEM). The Potter grinder was then washed with 250 ml of ultrapure water, and 500 l of 2% formic acid were added. The samples were then centrifuged for 15 minutes at 6000 rpm and at 4 C.

(26) In order to assay the glutathione coupled to the NEM (GS-NEM), 25 ml of the supernatant is diluted in 975 l of 1% formic acid (1/40) in a 1 ml vial. It is then assayed relative to a range of increasing concentrations of GS-NEM (50-100-200-300-400-500-600 nmol.Math.l.sup.1) prepared from a stock solution of GS-NEM at 1 mmol.Math.l.sup.1 (3.1 mg of GSH, i.e. 10 mol in 10 ml of a solution of NEM at 2.5 mmol.Math.l.sup.1). All of the analyses were carried out by LC/MS (Thermo Fisher Quantum ultra AM triple quadrupole mass spectrometer).

(27) ResultsConclusion:

(28) It was observed that the treatment of the tissues with solutions of oil of Achillea (0.01% by volume) and of lipoic acid (250 mmol.Math.l.sup.1) results respectively in an increase in the GSH level of 26.8+/6.1% and 52.0+/12.7% relative to the nontreated tissues.

(29) Since lipoic acid is known to increase the GSH level, this test makes it possible to validate the experiment.

(30) Thus, the essential oil of Achillea in accordance with the invention makes it possible to increase the intra-tissue glutathione concentration and, consequently, to prevent and/or treat the signs of skin ageing.

Example 4: Composition

(31) Face Cream

(32) TABLE-US-00002 Percentage by weight relative to the total weight Ingredients of the composition Powdered potassium sorbate 0.1 Xanthan: polysaccharides: 0.3 glucose/mannose/glucuronic acid (40/30/30) Mixture of plant origin of lecithin, fatty acids 5 and alcohols Essential oil of Achillea according to Example 1 0.5 First cold-pressed bio sunflower oil 20 Glyceryl stearate citric ester 2 Benzyl alcohol (and) dehydroacetic acid (and) 0.8 water Fragrance 0.45 Citric acid 0.1 Water qs 100