ORIGINAL PAPER Rhodiola rosea ability to enrich cellular antioxidant defences of cultured human keratinocytes Cinzia Calcabrini Æ Roberta De Bellis Æ Umberto Mancini Æ Luigi Cucchiarini Æ Lucia Potenza Æ Roberta De Sanctis Æ Vania Patrone Æ Carla Scesa Æ Marina Dacha ` Received: 6 May 2009 / Revised: 27 July 2009 / Accepted: 4 August 2009 / Published online: 25 August 2009 Ó Springer-Verlag 2009 Abstract Keratinocytes are cells strongly exposed to oxidative stress, but normally good equipped for antioxi- dant responses. However, it has long been suggested that exogenous antioxidants could play a useful role in mini- mizing the adverse skin responses associated with such oxidant species. In this work it was paid attention to the extract of Rhodiola rosea L. roots by using the phyto- complex as a whole because of the important activity of its composition and mutual distribution of its components. We have measured the protection afforded by the extract to reduced glutathione levels, glyceraldehyde-3-phosphate dehydrogenase activity, and thiobarbituric acid reactive substances levels in cultured human keratinocytes (NCTC 2544) exposed to different oxidative insults: Fe(II)/ascor- bate, Fe(II)/H 2 O 2 , and tert-butyl-hydroperoxide. We also have investigated the influence of the R. rosea extract on the production of intracellular reactive oxygen species and on the activity of antioxidant enzymes (catalase, superox- ide dismutase, glutathione peroxidase, and glutathione reductase). Furthermore, we have demonstrated that R. rosea extract was able to increase in a time- and dose- dependent manner the activity of the trans plasma mem- brane oxido reductase activity as an indirect evaluation of the intracellular redox status and this effect was already evident with small concentration of the extract and in a long time. As a result, NCTC 2544 are able to better counteract to several oxidative insults if incubated with R. rosea extract demonstrating a very good antioxidant activity of this phytocomplex. Keywords Antioxidant enzymes Á Human keratinocytes Á Oxidative stress Á Plasma membrane oxidoreductase Á Reduced glutathione Á Rhodiola rosea L. Introduction The relationship between oxidative stress and aging is up to now well-established. The skin, being exposed to high oxygen tension, UV light, electromagnetic fields and occasionally to oxidizing chemicals, is frequently exposed to radical species and, therefore, to oxidative stress [16, 18, 30, 40]. The ability of cells to protect themselves from oxidative damage is dependent upon their antioxidant capacity. Moreover, situations that cause impairment of cellular antioxidant capacity, such as depletion of intra- cellular reduced glutathione (GSH), inactivation of anti- oxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) are very dangerous for the maintaining of the correct redox state of the cells; for this reason the use of exogenous antioxidants could be advisable [16, 30]. In this work we herein investigate the protective effect of an aqueous extract of Rhodiola rosea L. (Crassulaceae) C. Calcabrini Á R. De Bellis (&) Á U. Mancini Á L. Cucchiarini Á L. Potenza Á R. De Sanctis Istituto di Chimica Biologica ‘‘Giorgio Fornaini’’, Universita ` degli Studi di Urbino ‘‘Carlo Bo’’, Via A. Saffi, 2, 61029 Urbino, PU, Italy e-mail: roberta.debellis@uniurb.it V. Patrone Istituto di Igiene, Universita ` degli Studi di Urbino ‘‘Carlo Bo’’, Urbino, PU, Italy C. Scesa Facolta ` di Medicina e Chirurgia, Universita ` Cattolica del Sacro Cuore, Rome, Italy M. Dacha ` Universita ` Campus Bio-Medico, Rome, Italy 123 Arch Dermatol Res (2010) 302:191–200 DOI 10.1007/s00403-009-0985-z