NZ237771A - Cosmetic compositions, particularly for acne treatment, containing an extract of zygophyllaceae of the genus larrea - Google Patents

Abstract

A cosmetic composition for combatting, in particular, the formation of acne papulopustules and cutaneous redness, characterized in that it contains an extract which can be obtained from the leaves and stems of at least one zygophyllaceae of the genus Larrea, in a concentration of 0.01 to 0.10 % expressed in polyphenols, in a suitable cosmetic base.

Description

New Zealand Paient Spedficaiion for Paient Number £37771 237 7 7 Priority Date(s): Complete Specification Filed: iQftptiI CIrrs: 2B"hAR'i993' Publication Date: P.O. Journal, No : ..J&feh MO DRAWINGS r N-Z-PA-reMTOFPtCE,,. J [0 APR 19'3 Patents Form No. 5 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION COSMETIC COMPOSITIONS CONTAINING AN EXTRACT OF A ZYGOPHYLLACEAE BELONGING TO THE GENUS LARREA WE, CLAUDE BONNE, a French citizen of 316 Avenue d'Occitanie - 34000 Montpellier France, DANIEL SINCHOLLE, a French citizen of 343 Avenue de la Tremoulette - St Clement Mie-WEi- La Riviere 34270 St Mathieu De Treviers, France, and ^MIGHAk DIOT, a French citizen of 2 Allee des Dimanches - 78430 Louveciennes France hereby declare the invention, for which We pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: (followed by page la) 2 3 7 7 7 1 a The present invention relates to a cosmetic composition which in particular prevents the formation of the papules and pustules characteristic of acne.

The present invention relates more particularly to a cosmetic composition containing as active ingredient an extract of the leaves and stems of at least one member of Zygophyllaceae belonging to the genus Larrea.

It is reported in the literature that Larrea extracts were used by the American Indians for the treatment of cancer as well as tubercolosis and renal infections. These empirical indications may have some foundation because recent scientific work has in fact shown that extracts of plants belonging to the Zygophyllaceae family do show an antitumor activity (KATO, R et al. Chemical Abstracts, vol. 100, 1984, N* 29365:3) as well as an antibacterial effect (KIMURA, M et al. Chemical Abstracts, vol. 101, 1984, N° 51606 p). Moreover, advantage is taken of the latter activity in various commercial preparations intended for the disinfection of the skin (LEWIS, W.H. in Medical botany plants affecting man's health. John Wiley and Sons, New York, 1977, p. 363, 366).

The applicants have discovered that, in addition to its known pharmacological effects, the Larrea extract exhibits a remarkable inhibitory activity towards the migration of leucocytes and that topical compositions containing from 0.01 to 0.1 % of polyphenols derived from the extract can prevent pustulation of the lesions in an experimental model of acne.

Acne vulgaris is a follicular dermatosis which affects adolescents and young adults with high frequency. It affects some pilosebaceous units of the O' / do/ / / 2 face and trunk called sebaceous follicles-. This disease manifests itself through polymorphic lesions : the primary lesion is the comedo from which inflammatory and cicatricial lesions may develop. The disorder may be reduced to a two-step sequence.

The first consists in the formation of a comedo : under the influence of various factors, principally that of androgens, the sebaceous gland secretes sebum, the triglycerides of which are hydrolysed by the lipases produced by the follicular flora. The free fatty acids formed and other metabolites produced by the flora then stimulate the formation of cohesive keratinized cells by the follicular infundibulum, thus forming a closed comedo.

The second step is characterized by the induction of an inflammatory papule or pustule : the closed comedo may either be transformed into an open comedo or cause the rupture of the follicular sac and the inflammatory lesions. Several factors combine to lead to the rupture of the epithelium, including : mechanical compression of the epithelial wall by the comedo and the release of lytic enzymes by the follicular flora. The passage of the contents of the comedo into the adjacent dermis induces the migration of leucocytes which, by sustaining the inflammation in their turn, create the papules and pustules characteristic of acne.

As a consequence of its inhibitory activity towards _ the migration of leucocytes,' the Larrea extract makes it possible to prevent the progression from comedones to unsightly papules and pustules.

Consequently, the present invention relates to cosmetic composition suitable for preventing the transformation of the comedones into papules and 237 7 7 3 pustules and the formation of cutaneous redness and comprises an extract obtainable from leaves and stems of at least one member of Zygophyllaceae belonging to the genus Larrea, at concentrations varying from 0.01 5 to 0.1 % as expressed in terms of the polyphenol content, in an appropriate cosmetic base.

The cosmetic composition according to the invention may also be used against minor cutaneous irritations such as those induced by insect stings and 10 superficial burns.

The present invention relates also to a method for preventing the formation of papules and pustules characteristic of acne, which comprises applying to the skin an extract obtainable from the 15 leaves and stems of at least one member of Zygophylla ceae belonging to the genus Larrea at a concentration from 0.01 to 0.10 % expressed in terms of the polyphenol content, in an appropriate cosmetic base.

The present invention relates also to a 20 process for the preparation of a composition according to the invention, comprising incorporating an extract obtainable from the leaves and stems of at least one member of Zygophyllaceae belonging to the genus Larrea at a concentration from 0.01 to 0.10 % expressed in 25 terms of the polyphenol content, in an appropriate cosmetic base.

In the present invention one of the three species of Larrea may be used : .Larrea divaricata Cav. 30 Larrea cuneifolia Cav.

Larrea tridentata Coult.

The extract of the leaves and stems may be obtained by maceration of powdered vegetal organs in propylene glycol, in particular with 3 to 10 parts by 2 3 7 7 71 4 weight of propylene glycol for one part of vegetal organs, in alcaline medium, for 24 to 48 hours at ambient temperature (15 to 25' C) . After filtration the extract has a polyphenol content of 0.5 to 5 %.

For example: the dry plant is pulverized so as to obtain a powder having an oversize with the screen of 1 mm mesh below 5 %.

To 1 kg of powder is added 1 liter of sodium hydroxide 0.1 N and 9 liters of propylene glycol. The mixture is maintained under low stirring (150 to 200 r p m) for 24 hours. The mixture is filtered so as to obtain a clear liquid extract. Seven liters of extract are thus obtained.

The polyphenol content is checked by titration with the Arnow reagent. The polyphenol content should not be lower than 0.5 %, expressed as nor-dihydroguaiaretic acid.

Hereafter "Larrea extract" will designate such an extract obtained by maceration with propylene glycol.

The following studies demonstrate the anti-acne activity of the active ingredient used in the present invention. 1 - Inhibitory activity towards the migration of leucocytes The migration of the neutrophilic leucocytes towards a sub-cutaneous site was triggered in the rat by the subcutaneous injection of 5 ml of a 1 % solution of carboxymethylcellulose in a sterile isotonic solution of sodium chloride.

Simultaneously, control rats received an injection of 0.1 ml of propylene glycol at the same site and treated rats received 0.1 ml 2 3 7 7 7 1 of Larrea extract containing 0.5 % of polyphenols. Six hours after these treatments, the inflammatory exudates were tapped by puncture and the leucocytes were counted in a Thomas cell after staining.

The results are presented in Table I. These results show that the Larrea extract inhibits the migration of the leucocytes towards the subcutaneous inflammatory site.

Table I Inhibitory activity towards the migration of leucocytes Larrea extract Leucocyte concentration x 10^/mm^ 0 40 - 2 + 21 - 1.5 2 - Inhibition of the pustulation of experimental acne lesions Experimental acne lesions were induced in the dorsal skin of rabbits. After shaving, scarifications were made with a scalpel and a homogenate of human epidermis was applied to the cutaneous incisions (the homogenate of epidermis, the model for comedo matter, was prepared from skin removed during the course of surgical operations for mammaplasty; the epidermis was collected by means of a cryomicrotome and homogenized in isotonic phosphate buffer).

Some scarifications were also treated topically with 0.05 ml of either propylene glycol or Larrea extract containing 0.5 % of polyphenols, used neat or after dilution. After 24 hours, the cutaneous lesions were examined "blind" by two observers and the clinical appearance of the lesion was used to evaluate the reaction on a scale of + 1 to + 4.

The results are presented in Table II. These results show that the Larrea extract prevents the inflammatory reaction induced by the comedo-mimetic matter. 2 3 7 7 71 6 Table II 2 - Inhibition of the pustulation of experimental acne lesions Larrea extract Comedo-mimetic Pustulation matter reaction 0 0 + 0 + ++++ 1/10 dilution + ++ neat + + The cosmetic compositions according to the invention may also contain, if necessary, any other substances known to have beneficial properties for the integument and, in particular, to have cosmetic activity in the care of skins with a tendency to acne. They may contain antiseptic, comedolytic and antiseborrheic agents, perfumes, preservatives and dyestuffs.

The cosmetic compositions according to the invention may be presented in all of the forms used in beauty care, creams or gels in jars or tubes, milks, lotions in glass or plastic bottles, ampoules or sprays.

Suitable excipients nay be used for each particular form. These excipients must meet all of the necessary requirements. As examples, mention may be made of : propylene glycol, glycerol, cetyl alcohol, polyols, phospholipids in the form of liposomes or as such, vegetable, animal and mineral oils, wetting agents, thickeners, stabilizing and emulsifying agents commonly used.

The various cosmetic forms mentioned above are prepared according to the methods used in this domain.

Examples of cosmetic compositions (in parts by weight) are given below : 3 s 7 1 - Aqueous-alcoholic lotion Larrea extract, 0.5 % polyphenols Cetyl alcohol Stearic acid Glycerol Na alginate Triethanolamine 95° Alcohol Water qs 2 - 0/W Milk Larrea extract, 0.5 % polyphenols Polyethoxyether phosphate of oleyl alcohol Cetyl alcohol Anhydrous lanolin Liquid silicone Wheat germ oil Juniper oil Stearic acid Triethanolamine Magnesium aluminium silicate Aromatic composition Preservatives Water qs 3 - Alcoholic hydrogel Larrea extract, 0.5 % polyphenols Antiseptic ingredients Triethylamine Carbopol 940 Alcohol qs 2 3 7 7 7 8 0 ' 4 - Glycerated hydrogel Larrea extract, 0.5 % polyphenols 7 Sodium alginate 8 Glycerol 25 % Borax solution in glycerol 20 Thymol 2 Water qs 100 - 0/W Cream Larrea extract, 0.5 % polyphenols 10 Wheat germ oil 7 Glycerol stearate 5 Propylene glycol 3 Triethanolamine 0.5 Soya lecithin 1 Preservatives qs Water qs 100 6 - W/0 Cream Larrea extract, 0.5 % polyphenols 8 Salicylic acid 0.5 Aluminium silicate 2 Titanium oxide 2 White beeswax 20 Paraffin oil 60 Water qs 100 23 7 7 7 9

Claims (6)

WHAT WE CLAIM IS:-

1. Cosmetic composition suitable for preventing in particular the formation of papules and pustules characteristic of acne and of cutaneous redness, comprising an extract obtainable from the leaves and stems of at least one member of Zygophyllaceae belonging to the genus Larrea at a concentration from 0.01 to 0.10 % expressed in terms of the polyphenol content, in an appropriate cosmetic base.

2. Composition as claimed in claim 1, in which the extract is an extract obtainable by maceration of the leaves and stems of Larrea in propylene glycol.

3. Process for the preparation of a composition as claimed in claim 1, comprising incorporating an extract obtainable from the leaves and stems of at least one member of Zygophyllaceae belonging to the genus Larrea at a concentration from 0.01 to 0.10 % expressed in terms of the polyphenol content, in an appropriate cosmetic base.

4. Process as claimed in claim 3, in which the extract is an extract obtained by maceration of the leaves and stems of Larrea in propylene glycol.

5. A cosmetic composition as claimed in claim 1 substantially as herein described with reference to any one of the examples.

6. A process as claimed in claim 3 substantially as herein described with reference to any one of the examples. CLAUDE BONNE, DANIEL SINCHOLLE AND MICHEL DIOT b srneys B & CAREY tr/specs/667072