Effect of ultraviolet radiation on the expression of pp38MAPK and furin in human keratinocyte‐derived cell lines

Abstract

SummaryBackground: Ultraviolet radiation (UVR) is known to induce the activation of stressinflammation signal transduction pathways, and to induce the activity of many proteases in skin cells. It is unknown whether the activation of proteases such as furin is related to changes in the phosphorylation status of p38MAPK. Methods: The effect of UVR on immortalized keratinocyte (HaCaT) and squamous cell carcinoma (Colo16) cells was investigated with respect to cell survival, phosphorylation of p38MAPK, and the proprotein convertase, furin. The cells were exposed to either a low or a high dose of UVA and/or UVB and the viability was monitored over 48 h, along with changes in the intracellular expression of p38MAPK and furin. Results: Low-dose UVA (2 kJ/m 2 ) and/or UVB (0.2 kJ/m 2 ) radiation had no effect on cell

UVB-Stimulated TNFα Release from Human Melanocyte and Melanoma Cells Is Mediated by p38 MAPK

“…When the cells were exposed to both UVA and UVB radiation, as it was not possible to simultaneously irradiate with both UV types they were exposed initially first to either UVA (denoted UVA + B) or UVB (denoted UVB + A). The irradiation protocol was performed as described by Huynh et al [61]. …”

“…The cells were harvested 0–120 min post-irradiation as previously described [17,61]. The nylon membranes were incubated with the relevant antibody [1:1000 phospho-p38 rabbit polyclonal antibody, 1:1000 phospho-JNK rabbit polyclonal antibody, 1:1000 phospho-IκBα mouse monoclonal antibody, 1:1000 β-actin (loading control)] overnight at 4 °C.…”

Effect of Novel Marine Nutraceuticals on IL-1α-Mediated TNF-αRelease from UVB-Irradiated Human Melanocyte-Derived Cells

“…As it is estimated that the UVB component of sunlight is 5%, we chose a dose of 2 kJ/m 2 which represents the UVB component of 1 MED of solar sunlight (40 kJ/m 2 ). The irradiation protocol was performed as described by Huynh et al [5]. …”

“…Cell viability was determined 24 h after-UV radiation using the Trypan Blue exclusion method as previously described [5]. …”

“…It is also involved in the release of pro-inflammatory cytokines, of which tumour necrosis factor α (TNF- α ) has been implicated in tumorigenic activities [4]. In order to mediate its effects, UV radiation is known to activate multiple signalling cascades such as the p38 mitogen-activated protein kinase (MAPK), c-Jun terminal kinase (JNK), extracellular signal-regulated kinase 1/2 (ERK1/2), and nuclear factor- κ B (NF κ B) pathways in skin cells [1, 5–7]. The role each of these pathways plays in mediating the release of cytokines such as TNF- α remains to be fully characterised.…”