MOISTURIZING. Pronalen fruit acids.

Transcription

1 MOISTURIZING Pronalen fruit acids

2 Pronalen fruit acids Lemon Passion fruit Grape Pineapple Lemon (Citrus limonum), passion fruit (Passiflora edulis), grape (Vitis vinifera) and pineapple (Ananas sativus) fruits. -Hydroxyacids: Citric, Glycolic, Tartaric and Lactic acids. These organic acids diminish corneocyte cohesion, affecting the thickness of the stratum corneum. They increase the moisturizing level of the skin. The final result is to improve the flexibility of the stratum corneum. PRONALEN FRUIT ACIDS AHA-5 (49570) Concentrated from lemon and passion fruit. Contains an approximate 5% of total AHAs (standardized in lactic acid, citric acid and tartaric acid). PRONALEN FRUIT ACIDS AHA-20 (49560) Concentrated from passion fruit, grape and pineapple. Contains an approximate 20% of total AHAs (standardized in glycolic acid, lactic acid, citric acid and tartaric acid). V09-05/ ,49530,49540,49560,

3 PRONALEN FRUIT ACIDS AHA-21 (49540) Concentrated from pineapple, grape, and passion fruit. Contains an approximate 21% of total AHAs (standardized in glycolic acid, lactic acid, citric acid and tartaric acid). PRONALEN FRUIT ACIDS AHA-35 (49470) Concentrated from passion fruit and lemon. Contains an approximate 35% of total AHAs (standardized in lactic acid, citric acid and tartaric acid). PRONALEN FRUIT ACIDS AHA-50 (49530) Concentrated from passion fruit, lemon, grape and pineapple. Contains an approximate 50% of total AHAs (standardized in glycolic acid, lactic acid, citric acid and tartaric acid). INTRODUCTION Hyperkeratinization is identified both clinically and histopathologically by a thickened stratum corneum that is usually more compact than normal. Hyperkeratinization is principally due to decreased rates of desquamation, which are due to increased corneocyte cohesion. Diseases in which abnormal keratinization consistently contributes to pathogenesis include the ichthyoses, acne, verrucae and keratoses of all types, psoriasis, some eczemas and ordinary dry skin. There are several substances controlling corneocyte cohesion: Water, retinoids, -hydroxyacids (AHA) and what seem to be their antagonists, some -acetoxy acids (AAA). V09-05/ ,49530,49540,49560,

4 Water The presence or absence of water influences not only the physical properties of the stratum corneum but also desquamation. The stratum corneum of "dry skin" is substantially thickened and it can be easily discernible clinically and histologically. α-hydroxy acids and α-acetoxy acids The AHA are a special group of organic acids found to diminish corneocyte cohesion. The AHA were first found to have their particular influence on corneocyte cohesion when their therapeutic topical effectiveness on ichthyosis was identified. They have also been found to have similar therapeutic use in all conditions of keratinization, i.e., corneocyte cohesion. The AHA do not cause disaggregation of corneocytes of the mature upper levels of the stratum corneum, as occurs with other agents that properly should be categorized as keratolytics, i.e., strong acids, strong alkalis, thiols, or other denaturants such as urea and lithium salts in high concentrations. Unlike those true keratolytics, the AHA exert their influence on corneocyte cohesiveness at the lower, newly forming levels of stratum corneum. This effect is clinically detectable by sheetlike separation of the stratum corneum when the stratum corneum is sufficiently thick for this effect to be apparent. The therapeutic result of AHA' promoting a thinner stratum corneum is not only to improve the skin surface cosmetically but also to improve the flexibility of the stratum corneum. Thickness of the stratum corneum normally and pathologically must be the net result of two categories of opposing factors, i.e., those that diminish corneocyte cohesion and those that enhance corneocyte cohesion. Deficiencies of AHA are not possible since their endogenous synthesis occurs constantly. However, some studies suggest the possibility of endogenous synthesis of molecules competing in function with vitamin A or AHA, namely, AAA. V09-05/ ,49530,49540,49560,

5 Intercorneocyte chemical bonds and bonds influences thereon Several types of bonds possibly account for intercorneocyte attachments. These include covalent bonds (i.e., disulfide, peptide, and polysaccharide) and noncovalent bonds. The most common nonionic bond is the hydrogen bond in which the bonding force is due to a hydrogen atom. The bond is weakened or broken by agents such as lithium bromide, urea, and alkalis that by this action function as chemical denaturants. The bond is also diminished by water by a factor of dilution because water molecules always form hydrogen bonds among themselves. In ionic bonds the bonding force is due to a negatively charged group (i.e., carboxy, sulfate, phosphate) in apposition to a positively charged group (i.e., amino group of basic amino acids). Three factors affect such ionic bonds and hence corneocyte cohesion: o The distance between the positive and negative groups. o The medium occupying the space between the positive and negative groups. o The number (density) of positive and negative groups. The influence of water, AHA, and retinoids on corneocyte cohesion seems in large part due to their actions on ionic bonds, and therefore a consequence of their effects on one or more of the foregoing three factors. When the stratum corneum becomes hydrated, the distance between corneocytes, i.e., between apposing charged groups on outer cell walls of corneocytes, is increased, with a resultant decrease in cohesion force. Of the charged groups functioning in ionic bonds, amino and carboxy groups are not as readily removed or rendered nonfunctional as are sulfate and phosphate groups. This is because of widespread epidermal hydrolytic enzymes such as sulfatases and phosphatases, which can readily hydrolyze phosphate and sulfate groups, decreasing their number in glycoproteins, mucopolysaccharides, sterols, and lipid phosphatides present in the outer cell walls of keratinocytes. V09-05/ ,49530,49540,49560,

6 It has been found recently that in X-linked ichthyosis there is a deficiency of sulfatase activity in skin fibroblasts, in whole epidermis, in cultured keratinocytes, and in the stratum corneum, as well as in other tissues. These findings suggest that interkeratinocyte and intercorneocyte sulfate groups are not diminished (as presumably they are normally by the action of sulfatase), with the result that the density of sulfate groups on cell walls remains abnormally high. Therefore, it is conceivable that the intercorneocyte bonding forces remain undiminished, desquamation is diminished, and the stratum corneum is thicker and more compact than normal. When applied topically to patients with any form of hyperkeratosis, a large group of AHA diminish the thickness of the stratum corneum by diminishing corneocyte cohesion. Although the mechanism of this effect is still unknown, it could be speculated that it is due to inhibition of enzymes involved with formation of ionic bonds. For example, AHA might compete for sulfate and phosphate in the reactions of sulfate transferase, phosphotransferase, or kinases that are involved with formation of sulfated and phosphorylated mucopolysaccharides, glycoproteins, sterols, and lipid phosphatides.it is known that certain AHA inhibit enzymatic activities of phosphotransferase and kinases. For example, citric acid significantly inhibits glucose-6-phosphotransferase and the activity of phosphofructokinase. Additionally, AHA themselves are known substrates for accepting phosphate groups to form phosphorylated AHA in certain metabolic pathways. Therefore, from what it is known it may be speculated that the AHA act to diminish corneocyte cohesion by interference with formation of ionic bonds, and that this action is mediated by interference with the functions of enzymes that form O-S and O-P linkages of sulfate and phosphate bonds, respectively. COSMETIC PROPERTIES Hyperkeratinization and acne AHA act at the stratum corneum level. They act on the cohesion between corneocytes in the deepest layers, so that they make the stratum corneum thinner and improve skin flexibility. Therefore, they have an interesting exfoliating activity at a corporal, facial and even at a capillary level. These compounds eliminate the excesses of seborrhoeic and other non beneficial V09-05/ ,49530,49540,49560,

7 substances from the skin surface for its healthy state, being useful in dandruff and acne cases. Follicular hyperkeratinization of keratosis pilaris and acneiform blackheads responds well to tropical AHA. Treatment of the former is with cream formulations and concentrations as used for dry skin. Applications are continued twice daily until all follicular impactions are dislodged, and thereafter as needed to maintain follicular orifices open. For treatment of blackheads of acne, liquid or gel vehicles are preferable to creams. Concentration of AHA may be varied from 5% to 10%, depending upon skin tolerance. Activity on the hair Nojiri M. et al. (2004) developed a technology based on AHA and solvents to eliminate the inner pores observed in damaged hair, which are responsible for giving the hair the unhealthy appearance. They used bleached straight hair samples from Japanese volunteers. The hair shafts were immersed into an aqueous solution with 4% malic acid, 10% benzyloxyethanol (BOE), and 15% ethanol, at 40ºC for 20, 40 or 60 minutes, and subsequently cleared with water. Besides improving the appearance of the hair, this AHA-based technology allowed to keep the hairstyle for a long time, even under humidity conditions. The action mechanism was different from the habitual polymer-based technology. It has been proposed that the strong hydrogen bonds between the malic acid anion and the NH segments of hair proteins are the basis for the long lasting hairstyle duration attained with the AHA treatment. This novel technology allows for hair fixation without loosing the natural texture. Ichthyosis Salicylic acid was found to be less effective than most AHA. Optimum effectiveness is achieved with unneutralized formulations as follows: glycolic acid, mandelic acid, saccharic acid, tartaric acid, malic acid at 5% to 10%. Lactic acid formulations partially neutralized with ammonium hydroxide have provided equivalent effectiveness in 8% to 12% concentrations. V09-05/ ,49530,49540,49560,

8 Dry skin In many ways ordinary dry skin is quite similar to ichthyosis. To find that AHA provide benefits beyond those obtained with hydration alone is therefore not surprising. The particular usefulness of AHA on dry skin is most readily appreciated in most severe cases in which use of moisturizing preparations has provided inadequate benefits. The added benefit of AHA is clinically perceived with the return from a conspicuously thick stratum corneum to a thin, more normal stratum corneum. Most AHA are physiologic, natural, and nontoxic substances. All members of the group promote natural keratinization and desquamation. Those with multiple hydroxyl groups are moisturizing antioxidants, and are especially gentle for sensitive skin (Yu, RJ. & Van Scott, EJ., 2002). This activity can be useful at a corporal level but also to more concrete zones and structures as hair, the scalp and the facial area. RECOMMENDED DOSE Product Hydration Exfoliation Pronalen AHA % - Pronalen AHA % 20-30% Pronalen AHA % 20-30% Pronalen AHA % 15-25% Pronalen AHA % 10-20% V09-05/ ,49530,49540,49560,

9 BIBLIOGRAPHY Control of keratinization with alpha- hydroxy acids and related compounds. Arch. Dermatol. 110, , Flesh, P., Esoda, EC.Deficient waterbinding in pathological horny layer. J. Invest. Dermatol. 28, 5-12, Van Scott EJ, Yu RJ. Greaves, M.Topical alpha- hydroxy acid derivative for relieving dry itching skin. Cosmetics & Toiletries, 105, 61-64, Hermitte, R. Aged skin, retinoids and alpha-hydroxy acids. Cosm. & Toil, 63-67, Hill, JC., White, RH., Baratt, MD., Migini, E. The skin plasticization effect of the medium chain 2-hyroxy acid and use of potentiators. J. Appl. Cosmetol, 6, 53-68, Middleton, JD. Development of skin cream designed to reduce dry and flaky skin. J. Soc. Cosm. Chem., 25, , Nojiri, M. et al. A novel technology for improving hair setting ability and its mechanism. J. Cosmet. Sci., 2004; 55 (Supplement): Van Scott, EJ., Yu, RJ. Hyperkeratinization, corneocyte cohesion, and alpha- hydroxy acids.j. Am. Acad. Dermatol. 11, , Yu, RJ. & Van Scott, EJ. Hydroxycarboxylic acids, N-acetylamino sugars, and N-acetylamino acids. Skinmed, 2002; 1 (2): V09-05/ ,49530,49540,49560,

10 PROVITAL. S.A. Pol. Ind. Can Salvatella Gorgs Lladó, Barberà del Vallès Barcelona (España) Tel. (+34) V06-02/ ,12310,12340,12350,12710,