TY - JOUR
T1 - JP-8 induces immune suppression via a reactive oxygen species NF-κβ-Dependent mechanism
AU - Ramos, Gerardo
AU - Limon-Flores, Alberto Y.
AU - Ullrich, Stephen E.
N1 - Funding Information:
U.S. Air Force Office of Scientific Research grant (FA9550-05-1-402); National Cancer Institute grants (CA131207 and CA112660); USAF Institute of Technology scholarship supported G.R.; and Cancer Center Support Grant from the National Cancer Institute (CA 16672) supported animal and histology facilities at the University of Texas, MD Anderson Cancer Center.
PY - 2009
Y1 - 2009
N2 - Applying jet fuel (JP-8) to the skin of mice induces immune suppression. JP-8-treated keratinocytes secrete prostaglandin E2, which is essential for activating immune suppressive pathways. The molecular pathway leading to the upregulation of the enzyme that controls prostaglandin synthesis, cyclooxygenase (COX)-2, is unclear. Because JP-8 activates oxidative stress and because reactive oxygen species (ROS) turn on nuclear factor kappa B (NF-κβ), which regulates the activity of COX-2, we asked if JP-8-induced ROS and NF-κβ contributes to COX-2 upregulation and immune suppression in vivo. JP-8 induced the production of ROS in keratinocytes as measured with the ROS indicator dye, aminophenyl fluorescein. Fluorescence was diminished in JP-8-treated keratinocytes overexpressing catalase or superoxide dismutase (SOD) genes. JP-8-induced COX-2 expression was also reduced to background in the catalase and SOD transfected cells, or in cultures treated with N-acetylcysteine (NAC). When NAC was injected into JP-8-treated mice, dermal COX-2 expression, and JP-8-induced immune suppression was inhibited. Because ROS activates NF-κβ, we asked if this transcriptional activator played a role in the enhanced COX-2 expression and JP-8-induced immune suppression. When JP-8-treated mice, or JP-8-treated keratinocytes were treated with a selective NF-κβ inhibitor, parthenolide, COX-2 expression, and immune suppression were abrogated. Similarly, when JP-8-treated keratinocytes were treated with small interfering RNA specific for the p65 subunit of NF-κβ, COX-2 upregulation was blocked. These data indicate that ROS and NF-κβ are activated by JP-8, and these pathways are involved in COX-2 expression and the induction of immune suppression by jet fuel.
AB - Applying jet fuel (JP-8) to the skin of mice induces immune suppression. JP-8-treated keratinocytes secrete prostaglandin E2, which is essential for activating immune suppressive pathways. The molecular pathway leading to the upregulation of the enzyme that controls prostaglandin synthesis, cyclooxygenase (COX)-2, is unclear. Because JP-8 activates oxidative stress and because reactive oxygen species (ROS) turn on nuclear factor kappa B (NF-κβ), which regulates the activity of COX-2, we asked if JP-8-induced ROS and NF-κβ contributes to COX-2 upregulation and immune suppression in vivo. JP-8 induced the production of ROS in keratinocytes as measured with the ROS indicator dye, aminophenyl fluorescein. Fluorescence was diminished in JP-8-treated keratinocytes overexpressing catalase or superoxide dismutase (SOD) genes. JP-8-induced COX-2 expression was also reduced to background in the catalase and SOD transfected cells, or in cultures treated with N-acetylcysteine (NAC). When NAC was injected into JP-8-treated mice, dermal COX-2 expression, and JP-8-induced immune suppression was inhibited. Because ROS activates NF-κβ, we asked if this transcriptional activator played a role in the enhanced COX-2 expression and JP-8-induced immune suppression. When JP-8-treated mice, or JP-8-treated keratinocytes were treated with a selective NF-κβ inhibitor, parthenolide, COX-2 expression, and immune suppression were abrogated. Similarly, when JP-8-treated keratinocytes were treated with small interfering RNA specific for the p65 subunit of NF-κβ, COX-2 upregulation was blocked. These data indicate that ROS and NF-κβ are activated by JP-8, and these pathways are involved in COX-2 expression and the induction of immune suppression by jet fuel.
KW - Cutaneous
KW - Cytokines
KW - Volatile organic compounds
KW - siRNA
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U2 - 10.1093/toxsci/kfn262
DO - 10.1093/toxsci/kfn262
M3 - Article
C2 - 19095747
AN - SCOPUS:61349108217
VL - 108
SP - 100
EP - 109
JO - Toxicological Sciences
JF - Toxicological Sciences
SN - 1096-6080
IS - 1
ER -