Science and Technology Production
Congress
Authorship
Cáceres L
;
PAZ, MARIELA LAURA
;
Contin M
;
Garcés M
;
Calabró V
;
Magnani ND
;
Tasat D
;
Tripodi V
;
Alvarez S
;
González Maglio DH
;
Marchini T
;
Evelson PA
Date
2018
Publishing House and Editing Place
Estudio Sigma SRL
Summary
Information provided by the agent in
SIGEVA
The exposure to environmental particulate matter (PM) induces pulmonary oxidative stress and inflammation. Alveolar macrophages are suggested to play a central role in this scenario, since they produce inflammatory mediators and reactive oxygen species (ROS) following PM uptake. The aim of our work was to characterize this inflammatory response and to address the main targets of the redox imbalance observed in macrophages after the exposure to Residual Oil Fly Ash (ROFA), a PM surrogate rich in...
The exposure to environmental particulate matter (PM) induces pulmonary oxidative stress and inflammation. Alveolar macrophages are suggested to play a central role in this scenario, since they produce inflammatory mediators and reactive oxygen species (ROS) following PM uptake. The aim of our work was to characterize this inflammatory response and to address the main targets of the redox imbalance observed in macrophages after the exposure to Residual Oil Fly Ash (ROFA), a PM surrogate rich in transition metals. The murine cell line RAW 264.7 was exposed to ROFA at 25, 50, or 100 μg/mL for 24 h. Cell viability was not significantly affected under these experimental conditions. Cell culture supernatants showed increased TNF-α levels after incubation with ROFA 100 μg/mL (control: 480±140 pg/mL TNF-α, p<0.01). Consistently, we observed increased CD80 expression and a 2-fold increase in MHC class II levels (control: 29±3 MHC class II+ cells, p<0.05) when exposed to the highest ROFA dose, assessed as mean fluorescence intensity (MFI) by flow cytometry. Intracellular redox status was evaluated as GSH and GSSG content by HPLC-MS, resulting in increased GSSG levels after incubation with ROFA 50 and 100 μg/mL (control: 0.50±0.06 nmol/mg protein, p<0.01), which led to a decrease in the GSH/GSSG ratio. Given that NADPH oxidase (NOX) is a major source of ROS production, we studied its activity and found a 2-fold increase after incubation with ROFA 100 μg/mL (control: 340±70 AU/min mg protein, p<0.05). These findings suggest that exposure to ROFA leads to inflammatory activation and intracellular redox imbalance in RAW 264.7 cells, which could be attributed to increased NOX activity. Taken together, these results contribute to the understanding of the molecular pathways triggered by air pollution derived PM exposure.
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Key Words
ROFAMACROPHAGESNADPH OXIDASEREDOX