PROTECTION FROM PHOTOAGING BY P. EMBLICA EXTRACT 55 increases ROS production, which induces the synthesis of matrix metalloproteinases (MMPs) that degrade collagen, causing skin photoaging. Collagen fi ber is primarily syn- thesized by fi broblasts as a pro-collagen protein, which is secreted and further processed to be a collagen fi ber in the extracellular matrix (15,16). Among collagens, type I is the most abundant and comprises between 85% and 90% of the total collagen in skin (9). Type 1 collagen damage by UVB irradiation results in photoaging. Strategies to prevent or at least minimize ROS-induced photoaging and intrinsic aging of the skin necessarily include protection against UV irradiation and antioxidant homeostasis (8). Due to their potent antioxidant activity, emblica extracts appear to have benefi ts as anti- aging actives. The level of procollagen type I protein in photoaged skin is lower than that in naturally aged skin. The level of matrix metalloproteinase-1 protein and the activity of matrix metalloproteinase-2 were higher in the dermis of photoaged skin than in naturally aged skin (10). Emblica extract stimulated proliferation of fi broblasts and also induced production of procollagen in human skin fi broblasts (17). It is known that ascorbic acid increases the photostability of collagen and that the colla- gen becomes less sensitive to UV radiation (18). The present study found that emblica extract signifi cantly protected normal human dermal fi broblasts from UVB-induced ROS generation and subsequent collagen damage. In addition, our results show that emblica has a greater potency than ascorbic acid. Moreover, only trace amounts of ascorbic acid have been recently reported in emblica fruits, suggesting that the antioxidant effects ex- hibited by emblica fruits are due to gallic acid esters (2). Our results suggest that the effi cacy of emblica extract in preventing UV-induced ROS generation and collagen dam- age may not be associated with its ascorbic acid content. The UV-protection effi cacy of a product depends signifi cantly either on its UV absor- bance/blocking effi cacy or its effi cacy in inhibiting UV-induced adversaries (ROS gener- ation, MMP generation, etc.) or both. Also, not all the antioxidants or MMP inhibitors are effective sunscreens and vice-versa. For example, octyl methoxycinnamate, zinc oxide, titanium dioxide, etc., are potential sunscreens but not potential antioxidants. Similarly, green tea (containing fl avonoid antioxidants), butylated hydroxytoluene, trolox, etc., are potential antioxidants but are not used as sunscreens. This may be because many of the antioxidants may not be stable under UV exposure to provide UV protection benefi ts. Ascorbic acid and emblica extract are potential antioxidants and are also used as sunscreens. Although there is enough literature on the antioxidant, MMP-inhibitory, and collagen- promoting properties of emblica extract that contribute to its UV-protection effi cacy, there was no signifi cant emphasis on the active constituents that contribute to its unique UVB-protection effi cacy. Earlier, it was thought that emblica fruits were rich in ascorbic acid (1), and it is obvious that ascorbic acid could have contributed signifi cantly to the UVB-protection effi cacy of emblica fruit extract. However, recent work on the character- ization of the emblica fruit extract indicates only trace amounts of ascorbic acid in the extract (2), and our work on its UVB-protection effi cacy in comparison to ascorbic acid indi- cates that the combination of various gallates (1-O-galloyl-β-D-glucose (β-glucogallin)) and mucic acid (1,4-lactone 5-O-gallate in the emblica extract) contributes to its UVB- protection effi cacy, making it a natural cosmetic, superior to a much-used cosmetic active, ascorbic acid. This composition is more stable under UV exposure and hence it could render its antioxidant and anti-infl ammatory benefi ts against UV-induced adversaries, unlike other antioxidants that may not be stable under UV exposure to provide UV-protection benefi ts.
JOURNAL OF COSMETIC SCIENCE 56 ACKNOWLEDGMENTS The authors thank Sami Labs Limited, Bangalore, India, for its fi nancial support. The authors thank all the scientists of the Biological Research Department of Sami Labs Limited for their support and cooperation. REFERENCES (1) P. Scartezzini, F. Antognoni, M. A. Raggi, F. Poli, and C. Sabbioni, Vitamin C content and antioxidant activity of the fruit and of the Ayurvedic preparation of Emblica offi cinalis Gaertn., J. Ethnopharmacol., 104, 113–118 (2006). (2) M. Majeed, B. Bhat, A. N. Jadhav, J. S. Srivastava, and K. Nagabhushanam, Ascorbic acid and tannins from Emblica offi cinalis Gaertn. Fruits—A revisit, J. Agric. Food Chem., 57, 220–225 (2009). (3) O. Bossi, M. Gartsbein, M. Leitges, T. Kuroki, S. Grossman, and T. Tennenbaum, UV irradiation in- creases ROS production via PKCdelta signaling in primary murine fi broblasts, J. Cell Biochem., 105, 194–207 (2008). (4) J. N. Ho, Y. H. Lee, J. S. Park, W. J. Jun, H. K. Kim, B. S. Hong, D. H. Shin, and H. Y. Cho, Protective effects of aucubin isolated from Eucommia ulmoides against UVB-induced oxidative stress in human skin fi broblasts, Biol. Pharm. Bull., 28, 1244–1248 (2005). (5) A. Oba and C. Edwards, Relationships between changes in mechanical properties of the skin, wrinkling, and destruction of dermal collagen fi ber bundles caused by photoaging, Skin Res. Technol., 12, 283–288 (2006). (6) Y. Xu and G. J. Fisher, Ultraviolet (UV) light irradiation induced signal transduction in skin photoag- ing, J. Dermatolog. Sci., Suppl. 1, S1–S8 (2005). (7) H. Masaki, Role of antioxidants in the skin: Anti-aging effects, J. Dermatol. Sci., 58, 85–90 (2010). (8) W. Ma, M. Wlaschek, I. Tantcheva-Poor, L. A. Schneider, L. Naderi, Z. Razi-Wolf, J. Schuller, and K. Scharffetter-Kochanek, Chronological ageing and photoageing of the fi broblasts and the dermal connective tissue, Clin. Exp. Dermatol., 26, 592–599 (2001). (9) J. H. Chung, H. R. Seo, H. R. Choi, M. K. Lee, C. S. Youn, G. Rhie, K. H. Cho, K. H. Kim, K. C. Park, and H. C. Eun, Modulation of skin collagen metabolism in aged and photoaged human skin in vivo, J. Invest. Dermatol., 117, 1218–1224 (2001). (10) P. Chanvorachote, V. Pongrakhananon, S. Luanpitpong, B. Chanvorachote, S. Wannachaiyasit, and U. Nimmannit, Type 1 pro-collagen promoting and anti-collagenase activities of Phyllanthus emblica extract in mouse fi broblasts, J. Cosmet. Sci., 60, 395–403 (2009). (11) R. S. Davidson and M. M. Hilchenbach, The use of fl uorescent probes in immunochemistry, Photochem. Photobiol., 52, 431–438 (1990). (12) M. Bergman, A. Perelman, Z. Dubinsky, and S. Grossman, Scavenging of reactive oxygen species by a novel glucurinated fl avonoid antioxidant isolated and purifi ed from spinach, Phytochemistry, 62, 753– 762 (2003). (13) A. R. Rosenkranz, S. Schmaldienst, K. M. Stuhlmeier, W. Chen, W. Knapp, and G. J. Zlabinger, A microplate assay for the detection of oxidative products using 2′,7′-dichlorofl uorescin-diacetate, J. Immunol. Methods, 156, 39–45 (1992). (14) R. W. Gracy, J. M. Talent, Y. Kong, and C. C. Conrad, Reactive oxygen species: The unavoidable envi- ronmental insult, Mutat. Res., 428, 17–22 (1999). (15) D. S. Greenspan, Biosynthetic processing of collagen molecules, Topics Curr. Chem., 247, 149–183 (2005). (16) E. G. Canty and K. E. Kadler, Procollagen traffi cking, processing and fi brillogenesis, J. Cell Sci., 118, 1341–1353 (2005). (17) T. Fujii, M. Wakaizumi, T. Ikami, and M. Saito, Amla (Emblica offi cinalis Gaertn.) extract promotes procollagen production and inhibits matrix metalloproteinase-1 in human skin fi broblasts, J. Ethnophar- macol., 119, 53–57 (2008). (18) N. O. Metreveli, K. K. Jariashvili, L. O. Namicheishvili, D. V. Svintradze, E. N. Chikvaidze, A. Sionkowska, and J. Skopinska, UV-vis and FT-IR spectra of ultraviolet irradiated collagen in the presence of antioxi- dant ascorbic acid, Ecotoxicol. Environ. Saf., 73, 448–555 (2010).
Previous Page Next Page