530 Soy isoflavones and nicotinamide down-regulate pro-inflammatory mediators in vitro

Abstract

530 Soy isoflavones and nicotinamide down-regulate pro-inflammatory mediators in vitro R Di Caprio, S Lembo, A Balato, F Gasparri and G Monfrecola 1 Deparment of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy, 2 Department of Medicine and Surgery, University of Salerno, Salerno, Italy, 3 Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy and 4 Department of Pharmacy (DIFARMA), University of Salerno, Salerno, Italy The aim of this study was to evaluate, in vitro, the anti-inflammatory and antioxidant properties of soy isoflavones and nicotinamide (NCT), singularly or in combination, in UVBirradiated keratinocytes. Soy isoflavones were used in two different forms: ISOSOY and Lo ISO-3s. The first, is a standardized glycine soy extract titrated to 90% in isoflavone aglycones (with genistein:daidzein1⁄41:4), soluble in dimethylsulfoxide. The second, consists in microencapsulated soy extracts, enriched in daidzein and genistein, obtained by spray-drying technique using a sodium-carboxymethylcellulose based matrix, soluble in water. Immortalized human keratinocytes were pre-incubated for 2h with ISOSOYand NCTor with Lo ISO3s and NCT, singularly or in combination, and irradiated with UVB 60 mJ/cm. Substances toxicity was assessed through cell viability and their possible anti-inflammatory effect was explored analyzing IL-6, TNF-a and COX-2 gene expression (qRT-PCR) 24h after UVB irradiation. None of the tested substances resulted toxic to cells. All of them showed anti-inflammatory properties alone or in combination with NCT. In detail, Lo ISO-3s was more effective than ISOSOY in down-regulating IL-6 and COX-2 increases (p<0.01), while ISOSOY was more effective than Lo ISO-3s in down-regulating TNF-a increases (p<0.01). A part from TNF-a, Lo ISO-3s was more effective than NCT in reducing UVB-induced inflammation, while ISOSOY, generally, resulted less effective. In conclusion, soy isoflavones and NCT, used alone or in combination, have demonstrated a potential immuno-modulatory and cytoprotective effect representing an interesting option to improve or prevent UV-induced/aggravated clinical conditions. 531 Human skin mast cells express photoreceptors H Siiskonen, S Buscone, I Castellano Pellicena, A Smorodchenko, NE Uzunbajakava, NV Botchkareva, M Maurer and J Scheffel 1 Faculty of Life Sciences, Centre for Skin Sciences, Bradford, United Kingdom, 2 Dermatology, Kuopio University Hospital, Kuopio, Finland, 3 Department of Dermatology and Allergy, Charite Universitatsmedizin Berlin, Berlin, Germany and 4 Philips Research Eindhoven, Eindhoven, Netherlands Circadian clocks critically influence mast cell (MC) functions and drive the daily rhythms in IgE/MCemediated allergic reactions. In the skin, these clocks may be regulated by photoreceptors (PRs) such as cryptochromes (CRY) and opsins (OPN), which have recently been shown to be expressed in keratinocytes. Whether skin MCs express PRs has not been investigated yet. Therefore, we studied the expression of selected PRs in human MCs using qRT-PCR. To this end, we used freshly isolated cutaneous MCs from breast (n1⁄43), eyelid (n1⁄41) and abdominal skin (n1⁄41); cultured MCs from breast (n1⁄42) and foreskin (n1⁄42); cultured CD34-positive peripheral blood stem cell-derived MCs (PSCMCs); and LAD2-MCs. We identified that freshly isolated MCs from breast skin, cultured MCs from breastand foreskin and LAD2-MCs express CRY1, OPN1 medium-wave-length, OPN2 and OPN3. Expression of CRY1, OPN1 medium-wave-length and OPN3 was also detected in freshly isolated MCs from eyelid skin. Of the PRs assessed, CRY1 was the most prominently expressed, and we also found CRY1 expression at the protein level in cultured MCs from breast skin and foreskin and from freshly isolated MCs from breast skin. The expression levels of PRs varied between different donors and skin areas. MCs freshly isolated from abdominal skin and PSCMCs were negative for the investigated PRs, suggesting that expression of CRYs and OPNs might be connected to MC differentiation and functionality. Our results show, for the first time, that human skin MCs express several PRs. We will next investigate a potential role of these PRs in MCs by studying their involvement in circadian oscillation of MC function and in MCmediated skin responses.