FR2811226A1 - Cosmetic composition for treatment of aging or dehydrated skin contains vegetable protein having trypsin inhibiting activity or vegetable extract rich in such protein - Google Patents

Abstract

Cosmetic composition for skin treatment, containing vegetable protein or vegetable extract with trypsin-inhibiting activity, is new. Independent claims are also included for: (1) use of vegetable trypsin inhibitor or plant extract containing such inhibitor as active agent for protection or regeneration of skin collagen; and (2) a process of cosmetic treatment of aging or dehydrated skin comprising topical application of sufficient quantity of vegetable trypsin inhibitor or plant extract containing such inhibitor.

Description

MOISTURIZING COSMETIC COMPOSITION COMPRISING A

PLANT TRYPSIN INHIBITOR.

  The present invention relates to cosmetic compositions, possibly dermatological, for skin care, in particular for combating aging or for moisturizing the skin based on plant extract. More particularly, the compositions of the invention are based on an understanding of the role of skin collagen, in particular because of its ability to fix water and

  the impact of its degradation during aging (C.

  Durandeau et al., S.T.P. Pharma 5 (89), 541-547, 1989). Numerous cosmetic preparations based on collagen have thus been proposed in the prior art for their

hydrating power.

  The Applicant is now interested in the phenomenon of destruction of skin fibers by proteases and more particularly skin collagen

  by collagenases (L. Robert and A.M Robert, J. Med. Est.

  And Chir. Derm., Vol. XX, 80, December 93, 211-217). However, the cutaneous maturation of collagenases requires the intervention of another proteolytic enzyme which is trypsin. Indeed, this protease plays a particular role in the skin where fibroblasts synthesize many enzymes, collagenase, whose essential function is known in the renewal of the extracellular matrix and the aging of the skin. Like many enzymes, it is produced in the form of an inactive pro-collagenase which is cleaved by trypsin

to be active.

  The present invention therefore relates to a cosmetic composition for the skin, characterized in that it comprises a vegetable protein or an extract

  plant with trypsin inhibiting activity.

  The invention naturally envisages a cosmetically acceptable vegetable protein and preferably a vegetable extract rich in such a protein. A cosmetic composition according to the invention is therefore remarkable in that it makes it possible to control the collagenase activity in the tissues by lowering the level of trypsin or by inhibiting it so as to block the cascade of activation of the matrix proteases

  extracellular and thus regenerate the collagen in the skin.

  The invention thus provides novel methods of cosmetic treatment of aging or dehydration of the skin by topical application to a subject of an effective amount of a plant trypsin inhibitor or a plant extract containing such a

  inhibitor, and especially those described below.

  The Applicant is particularly interested in a class of protease inhibitors, designated Bowman-Birk inhibitors. These inhibitors have

  previously described as exhibiting anti

  elastic, anti-inflammatory. Inhibitors of this class also have two active sites capable of each inhibiting a protease. Thus in the presence of Bowman-Birk inhibitor, trypsin and chymotrypsin lose their lytic activity. The subject of the invention is therefore the use of a plant trypsin inhibitor, in particular a Bowman-Birk type inhibitor or a plant extract rich in one of these inhibitors as active agent in the protection or regeneration of the skin collagen and therefore useful for the preparation of a composition

  cosmetic, in particular anti-aging or moisturizing.

  Among the Bowman-Birk inhibitors, the invention specifically targets a plant protein called prohibin, the presence of which has been described in several legumes such as soybeans, peas and faba beans, all sharing a great sequence homology. The invention relates very preferably to the prohibin of Phaseolus lunatus whose common name is Lima bean. Phaseolus lunatus is widespread in Central America and South America. It is a bushy plant reaching 50 cm at maturity and producing pods from which beans are accommodated in various culinary preparations. The bean is rich in protein (21%), carbohydrates (63%) and mineral salts (2.4%) but contains very little lipid (0.6%). The prohibin is a protein synthesized by the plant probably as a stabilizing system of the seed awaiting germination or is used as defense against the attacks of insects which produce proteinases. The present invention therefore relates very specifically to a cosmetic composition comprising a plant protein inhibiting trypsin belonging to the class of Bowman-Birk inhibitors or a plant extract rich in this protein. Advantageously, the invention relates to a composition comprising an extract of legumes such as soybeans, peas, faba beans, or very preferably, of Phaseolus lunatus. It is a protein extract or an extract rich in protein having a trypsin inhibiting activity which can be obtained by extraction and isolation, or even more or less thorough purification, according to techniques

known to those skilled in the art.

  It has been shown in the context of the present invention that the enzymatic activities of trypsin and chymotrypsin decrease in a dose-dependent manner, the inhibition being total at 0.01% and already significant at 0.0005%. A cosmetic composition according to the invention therefore comprises from 0.05 to 10% and preferably from 0.1 to 5% by weight of the total composition of vegetable protein or

  plant extract rich in this protein.

  Prohibin is a protein of about 8000 daltons which does not have direct enzymatic activity, but its three-dimensional structure gives it a conformation in space which makes it affine for the two proteolytic enzymes which are trypsin and chymotrypsin. Consequently, to be active, the prohibin must be advantageously dissolved in a medium allowing it to maintain its conformation. However, the solubilization of prohibin in a medium compatible with a cosmetic formulation poses difficulties which the present invention specifically intends to solve. Indeed, prohibin is a water-soluble product which is hardly compatible with surfactants which constitute an unfavorable environment by deformation of the structure.

  tertiary and lead to inactivation of the protein.

  The invention relates to this effect most preferably to a cosmetic composition comprising an aqueous phase containing a plant protein or a plant extract having a trypsin inhibiting activity. It may then be a lotion, but advantageously, a cosmetic composition according to the invention comprises two distinct phases, said aqueous phase and an oily phase, which are mixed by

shaking before use.

  The oily phase or fatty phase makes it possible to give the composition of the invention more "glide" and "richness". Preferably, the weight ratio between the oily phase and the aqueous phase is of the order of 20/80. A composition according to the invention may comprise other active agents, in particular hydrating agents such as: - An alga extract, for example an extract of Himanthalia elongata, which is a brown alga from the fucales family from which one extracts and purifies the intracellular content. Such an extract is rich in proteins, trace elements, mannitol and vitamins which gives it moisturizing properties. A composition according to the invention can comprise of the order of 0.1 to 5% of such an extract. - An extract of Pinus Lambertiana or Pinus Sylvestris, which is a New Zealand pine, an extract of the trunk and leaves of which is very rich in cyclidol (D-pintol). It is a sugar constituting a major oligosaccharide which contributes to the survival of certain species subjected to saline stress. This sugar also has stabilizing properties on the membranes, which give this extract moisturizing properties on the skin. A composition according to the invention can

  comprise of the order of 0.1 to 5% of such an extract.

  - An extract of cactus flower, more particularly of Cereus gandiflorus originating from the Antilles and Central America. It is a glycolic extract from cactus flowers that contains phenolic compounds and softening and moisturizing alkaloids for the skin. A composition according to the invention can

  comprise of the order of 0.1 to 5% of such an extract.

  - An extract of white lupine. It is a protein extract of lupinus albus rich in low molecular weight glutamine peptides and in oligosaccharides. It strengthens the skin barrier by stimulating the synthesis of lipids and proteins specific to the epidermis, thus limiting water loss and therefore allowing better hydration of the stratum corneum. A composition according to the invention can

  comprise of the order of 0.1 to 5% of such an extract.

  Other advantages and characteristics of the invention will appear from the following examples concerning the anti-trypsin and antichymotrypsin activity

  prohibin and compositions according to the invention.

  1) Anti-trypsin and anti-chymotrypsin activity

prohibin.

  The ability to inhibit trypsin and

  prohibin chymotrypsin has been demonstrated in vitro.

  Two substituted amine esters, N-x-benzoyl-arginine

  ethyl ester (BAE) for trypsin and N-X-benzoyl-

  tyrosine ethyl ester (BTEE) for chymotrypsin, were used as specific substrates. After hydrolysis of the ester function, the appearance of the released amine-benzoyl

  is followed by optical density at 256 nm.

  The protein was tested at 6 different concentrations and the trypsin and chymotrypsin activities were evaluated by their capacity to release the specific amine. Figure 1 in the appendix represents the percentage of hydrolysis rates in the presence of increasing concentrations of prohibin relative to the maximum rate

  hydrolysis of enzymes without prohibin.

  For chymotrypsin, which is the most strongly inhibited enzyme, the decrease in activity measured by the rate of hydrolysis of the amino substrate is given in the

table 1 below.

  Table 1 Protein (prohibin) (%) Chymotrypsin (%)

10-4 - 38

1.2. 10-3 - 62

2.5. 10-3 - 90

10-3 - 96

-2 - 100

  2) Example of a two-phase hydrating serum according to

1 invention.

  Aqueous phase Purified water QSP 100,000 Synthetic hydrating film-forming polymer 10,000 Glycerin 10,000 PCANa 9,000 Dipropylene glycol 5,000 Prohibin 1,000 Himanthalia elongata 2,000 Cactus flower extract 1,000 White lupine extract 1,000 Pinus sylvestris extract 1,000 Triethanolamine 0.300 Sodium chloride 0.300 Xanthan gum 0.200 Preservatives 0.500 Sequestering agent 0.100 Coloring solution 0.200 Oily phase Perhydrosqualene 40,000 Isohexadecane 37,000 Fatty acid ester 20,000 Perfume 1,800 Vitamin E derivative 1,000 Anti-oxidant 0.200

Claims (8)

  1) Cosmetic composition for the skin, characterized in that it comprises a plant protein or a plant extract having an inhibitory activity trypsin.   2) Cosmetic composition according to claim 1, characterized in that it comprises a plant protein inhibiting trypsin belonging to the class of Bowman-Birk inhibitors or a plant extract rich in this protein.   3) Cosmetic composition according to one of   Claims 1 or 2, characterized in that it comprises   a protein or legume extract such as soy,   pea, faba bean, or Phaseolus lunatus.   4) Cosmetic composition according to one of   Claims 1 to 3, characterized in that it comprises   a Phaseolus lunatus protein with a molecular weight of approximately 8000 having a trypsin and chymotrypsin inhibiting activity or a protein extract of   Phaseolus lunatus containing this protein.   ) Cosmetic composition according to one of   Claims 1 to 3, characterized in that it comprises   from 0.05 to 10% and preferably from 0.1 to 5% by weight of the total composition, of a vegetable protein or of an extract vegetable rich in this protein.   6) Cosmetic composition according to one   any of the preceding claims, characterized in   what it comprises an aqueous phase containing a plant protein or a plant extract having a trypsin inhibiting activity.   7) Cosmetic composition according to one   any of the preceding claims, characterized in   that it comprises two distinct phases, an aqueous phase and an oily phase, said aqueous phase containing a vegetable protein or a plant extract   exhibiting trypsin inhibiting activity.   8) Cosmetic composition according to one   any of the preceding claims, characterized in   what it includes one or more active agents chosen from: an algae extract, for example an extract of Himanthalia elongata, an extract of Pinus Lambertiana or Pinus Sylvestris, an extract of cactus flower, a white lupine extract.   9) Use of a plant trypsin inhibitor or a plant extract containing such an inhibitor as an active agent in the protection or   regeneration of skin collagen.   ) Method of cosmetic treatment of aging or dehydration of the skin by topical application to a subject of an effective amount of a plant trypsin inhibitor or an extract of plant containing such an inhibitor.