Ellular ROS productionAAALAC ccredited facility maintained on a 12 h light/ dark cycle. Food and water were provided ad libitum except during the DEP exposures. Mice were acclimated to the facilities and nose-only exposure tubes prior to use. All procedures were approved by the Institutional Animal Care and Use Committee.Cytomix treatmentChanges in generic ROS production were evaluated by incubating LA-4 cells for 30 min with the non-specific UNC0642 site fluorescent probe, 2′,7′-dichloro-fluorescein diacetate (H2DCFDA; 10 M; Invitrogen, Carlsbad, CA) followed by exposure to DEP for 2 h. Fluorescence was quantified using a fluorescence plate reader. Changes in intracellular O2- levels were detected in LA-4 cells grown on chamber slides and incubated for 30 min with the probe, dihydroethidium (DHE; 10 M; Invitrogen, Carlsbad, CA) and then exposed to DEP for 2 h. Cells were imaged using a fluorescent microscope (Nikon Eclipse Ti; Nikon Elements software; Nikon Instruments, Inc.).SOD ActivityMice were briefly anesthetized with vaporized isoflurane (Webster Veterinary Supply Inc., Sterling, MA) to administer 50 L of either sterile PBS or cytomix into the lungs via oropharyngeal aspiration. Based on dose-range finding studies with these cytokines individually, and in combination (data not shown), the cytomix regimen used herein consisted of a single treatment with TNF (1.0 ng/g of body weight) + IL-1 (0.5 ng/g) + IFN (2.0 ng/g) R D Systems, Minneapolis, MN.DEP exposuresAfter probe sonication, cell lysates were placed in cold 20 mM HEPES buffering solution, centrifuged, and supernatants assayed for SOD activity as per the manufacturer’s instructions (RANSOD, RANDOX Laboratories Ltd, Co., Antrim, UK).GlutathioneAs described previously [25], dislodged LA-4 cells were treated with cold 10 perchloric acid containing 0.4 M boric acid (Sigma, St. Louis, MO). After centrifugation (20 min, 4 , 20,000 g), cell-free supernatants were treated with dansyl chloride (Sigma) to label the reduced (GSH) and disulfide (GSSG) glutathione fractions. After gradient HPLC separation (Discovery C18 columns; Sigma), the fluorescent products of dansylated GSH and GSSG, as well as GSH and GSSG standards, were acquired (excitation at 335 nm; emission at 515 nm) using a fluorescence detector PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/27872238 (Model 1100; Agilent Technologies, Santa Clara, CA) and quantified (ChomPerfect Chomatography Data System software; Justice Laboratory Software, Denville, NJ).DEP inhalation exposures MiceUsing the EPA string-generation particle exposure system, mice were placed in separate 24-port nose-only flow-by inhalation chambers and exposed to filtered air or resuspended DEP [81]. Particle concentration and size distribution were monitored and confirmed as previously described [82]. A pilot inhalation study in healthy mice was performed to determine a DEP exposure regimen that would induce mild, but detectable, lung inflammation. In the formal DEP inhalation study (Figure 1B), mice were pre-treated (Day 0) with phosphate-buffered saline (PBS) or cytomix as above, and 48 h later underwent nose-only inhalation exposure to filtered air or DEP (2.0 mg/m3) for two consecutive days (4 h/d ?2 d) (Day 2 and 3). Mice were euthanized (Day 4) via anesthetic overdose (Euthasol, 150?00 mg/kg, i.p.) followed by exsanguination. In a subset of mice, FeTMPyP was administered (10 mg/kg, i.p.) 24 h prior to cytokine treatment and daily until euthanasia (Day -1 to 4).In vivo assessmentsFemale BALB/c mice (Charles River Labs,.
