Title |
Lysosomal exocytosis and caspase-8-mediated apoptosis in UVA-irradiated keratinocytes
|
---|---|
Published in |
Journal of Cell Science, January 2013
|
DOI | 10.1242/jcs.130633 |
Pubmed ID | |
Authors |
Hanna Appelqvist, Petra Wäster, Ida Eriksson, Inger Rosdahl, Karin Öllinger |
Abstract |
Ultraviolet (UV) irradiation is a major environmental carcinogen involved in the development of skin cancer. To elucidate the initial signaling during UV-induced damage in human keratinocytes, we investigated lysosomal exocytosis and apoptosis induction. UVA, but not UVB, induced plasma membrane damage, which was repaired by Ca(2+)-dependent lysosomal exocytosis. The lysosomal exocytosis resulted in extracellular release of cathepsin D and acid sphingomyelinase (aSMase). Two hours after UVA irradiation, we detected activation of caspase-8, which was reduced by addition of anti-aSMAse. Furthermore, caspase-8 activation and apoptosis was reduced by prevention of endocytosis and by the use of cathepsin inhibitors. We conclude that lysosomal exocytosis is part of the keratinocyte response to UVA and is followed by cathepsin-dependent activation of caspase-8. The findings have implications for the understanding of UV-induced skin damage and emphasize that UVA and UVB initiate apoptosis through different signaling pathways in keratinocytes. |
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United Kingdom | 1 | 100% |
Demographic breakdown
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Science communicators (journalists, bloggers, editors) | 1 | 100% |
Mendeley readers
Geographical breakdown
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France | 1 | 3% |
Unknown | 35 | 97% |
Demographic breakdown
Readers by professional status | Count | As % |
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Researcher | 7 | 19% |
Student > Bachelor | 7 | 19% |
Student > Ph. D. Student | 6 | 17% |
Student > Doctoral Student | 4 | 11% |
Professor | 3 | 8% |
Other | 8 | 22% |
Unknown | 1 | 3% |
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Medicine and Dentistry | 5 | 14% |
Immunology and Microbiology | 2 | 6% |
Neuroscience | 1 | 3% |
Other | 0 | 0% |
Unknown | 4 | 11% |