Detection of key enzymes, free radical reaction products and activated signaling molecules as biomarkers of cell damage induced by benzo[a]pyrene in human keratinocytes.
Toxicol In Vitro
; 28(5): 875-84, 2014 Aug.
Article
en En
| MEDLINE
| ID: mdl-24685774
ABSTRACT
Benzo[a]pyrene (BaP) is a known carcinogenic and cell damaging agent. The underlying cell damaging pathomechanisms have not been totally revealed. Especially BaP-related induction of oxidative and nitrosative stress has not been previously investigated in detail. The presented study investigated these effects in order to elucidate the pathomechanism and as well to identify potential biological markers that may indicate a BaP exposure. Human immortalized keratinocytes (HaCaT cells) were exposed to BaP (1 µM) for either 5 min or 6 h, respectively. BaP-induced cellular damage was evaluated by immunocytochemistry analysis of multiple signaling cascades (e.g. apoptosis, Akt, MAPK, NOS, nitrotyrosine and 8-isoprostane formation), detection of nitrosative stress using diaminofluorescein (DAF-FM) and oxidative stress using 3' -(p-aminophenyl)fluorescein (APF). Our results show that BaP exposure significantly enhanced NO and ROS productions in HaCaT cells. BaP led to eNOS-phosphorylation at Ser(1177), Thr(495) and Ser(116) residues. Using specific inhibitors, we found that the Erk1/2 pathways seemed to have strong impact on eNOS phosphorylation. In addition, BaP-induced apoptosis was observed by caspase-3 activation and PARP cleavage. Our results suggest that BaP mediates its toxic effect in keratinocytes through oxidative and nitrosative stress which is accompanied by complex changes of eNOS phosphorylation and changes of Akt and MAPK pathways.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Benzo(a)pireno
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Carcinógenos
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Queratinocitos
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Proteínas Quinasas Activadas por Mitógenos
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Óxido Nítrico Sintasa de Tipo III
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Proteínas Proto-Oncogénicas c-akt
Tipo de estudio:
Diagnostic_studies
Límite:
Humans
Idioma:
En
Revista:
Toxicol In Vitro
Asunto de la revista:
TOXICOLOGIA
Año:
2014
Tipo del documento:
Article