β-Carotene Interferes with Ultraviolet Light A-Induced Gene Expression by Multiple Pathways  Karin Wertz, Petra Buchwald Hunziker, Nicole Seifert, Georges Riss, Martin Neeb, Guido Steiner, Willi Hunziker, Regina Goralczyk  Journal of Investigative Dermatology  Volume 124, Issue 2, Pages 428-434 (February 2005) DOI: 10.1111/j.0022-202X.2004.23593.x Copyright © 2005 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 1 Model of molecular events, as deduced from the array data. (a) β-carotene (βC) effects in unirradiated keratinocytes; (b) ultraviolet light A (UVA) effects in keratinocytes; (c) βC effects in UVA-irradiated keratinocytes. Genes labeled red were upregulated, genes labeled green were downregulated by the treatment. βC quenched the UVA effect for genes labeled blue. Journal of Investigative Dermatology 2005 124, 428-434DOI: (10.1111/j.0022-202X.2004.23593.x) Copyright © 2005 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 2 β-carotene downregulated (a) integrin α6 expression in irradiated and unirradiated HaCaT cells. βC enhanced ultraviolet light A (UVA)-induced (b) GADD34 and (c) GADD153 expression. Cells were supplemented with βC for 2 d and prior to UVA irradiation (270 kJ per m2) either in normal phosphate-buffered saline (PBS) or D2O-PBS. Gene expression 5 h after irradiation was determined by quantitative real-time RT-PCR. Values are geometric mean±standard error of three experiments. Journal of Investigative Dermatology 2005 124, 428-434DOI: (10.1111/j.0022-202X.2004.23593.x) Copyright © 2005 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 3 β-carotene (βC) concentration dependently induced caspase-3 activity in ultraviolet light A (UVA)-irradiated keratinocytes. Cells were supplemented with βC for 2 d and prior to UVA irradiation (270 kJ per m2). Caspase-3 activity was determined at 5 h after irradiation. Values are mean±standard error of an experiment with four replicates. Journal of Investigative Dermatology 2005 124, 428-434DOI: (10.1111/j.0022-202X.2004.23593.x) Copyright © 2005 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 4 Proposed relationship of the modes of action of β-carotene to its influence on ultraviolet light A-induced biological processes. Journal of Investigative Dermatology 2005 124, 428-434DOI: (10.1111/j.0022-202X.2004.23593.x) Copyright © 2005 The Society for Investigative Dermatology, Inc Terms and Conditions