P-143 Disruption of protein homeostasis: a potential bio- marker of exposure to three metal oxide nanoparticles Zahra M. Doumandji, Bertrand Rihn, Olivier Joubert UMR 7198, Institut Jean Lamour, Université de Lorraine, Nancy, France Introduction: The paucity of biomarkers to predict nanoparticle (NP) toxicity makes important the identification of key cellular pathways linked to a toxic exposure to NP. In this study, we used a lung macrophage cellular model (NR8383) to evaluate modifications in gene expression profiles after exposure to NPs of ZnO, ZnFe 2 O 4 and Fe 2 O 3 . Methods: The cytotoxic potency of NP was evaluated by WST1 assay and extracellular LDH measurement. Cellular pathway and relevant gene ex- pression were analyzed by a transcriptomic approach and real-time PCR. Results: WST-1 assay showed a significant reduction of NR8383 viability after exposure to the NP. Genomic study showed 985,1216, 4593 differ- entially expressed genes (DEGs) of cells exposed to ZnO, ZnFe 2 O 4 , and Fe 2 O 3 .NP, respectively. The major altered pathways were protein synth- esis, cellular metabolism, inflammatory and stress responses. The main affected pathways were eukaryotic Initiation Factor2 (eIF2) signaling, mTOR signaling and protein ubiquitination. Conclusions: The overall results indicate that the three NP are largely in- volved in the disruption of protein homeostasis. Some of the pathways altered have direct or indirect links to adverse outcomes. The eIF2 sig- naling for e.g. has been implicated in pro-inflammation responses. E-mail address: zahra-manel.doumandji@univ-lorraine.fr http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.290 P-144 The redox regulation of damage-associated mole- cular pattern molecule HMGB1 in pulmonary disease Alex Gauthier 1 , Ravi Sitapara 1 , Mao Wang 1 , Dan Antoine 2 , Lin Mantell 1 1 St. John's University, New York, NY, USA 2 Edinburgh Medical School, Edinburgh, UK HMGB1 is an endogenous molecule that can initiate and perpetuate inflammation. Previously, we have shown that airway HMGB1 mediates hyperoxia-induced acute lung injury and compromised innate immunity in cystic fibrosis and ventilator-associated pneumonia. To determine the redox state of HMGB1 and its effects on acute lung injury and innate immunity under hyperoxic conditions, LC-MS/MS was used to analyze HMGB1 in either bronchoalveolar lavage fluid (BAL) of mice or media of cultured macrophages exposed to 95–99% O 2 . MS/MS analysis indicated nuclear HMGB1 in both 95% and 21% O 2 groups was in its reduced form, but in BAL or culture media, all three critical redox forms of HMGB1 were present. Extracellular HMGB1 was not detected in BAL or cultured mac- rophages that remained at 21% O 2 . GTS -21, a drug which can improve macrophage functions and alleviate hyperoxia-induced acute lung injury, kept extracellular HMGB1 in the reduced form. These data suggest that hyperoxia-induced oxidative modifications of HMGB1 occurred after its release into the airways. Strategies to prevent HMGB1 from oxidation may provide an effective approach to treat patients on ventilation with either lung injury and/or compromised host defense against bacterial infections. E-mail address: alex.gauthier15@stjohns.edu http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.291 P-145 Hyperoxia-induced macrophage dysfunction and acute lung injury are attenuated by modulation of α7nAChR via reduced HMGB1 hyperacetylation and release Alex Gauthier 1 , Ravi Sitapara 1 , Ganesh S. Thakur 2 , Lin Mantell 1 1 St. John's University, New York, NY, USA 2 Northeastern University, Boston, MA, USA Prolonged exposure to hyperoxia during mechanical ventilation (MV) can result in acute lung injury (ALI) and is associated with HMGB1 ac- cumulation in the airways. The aim of this study was to determine whether modulation of α7 nicotinic acetylcholine receptor (α7nAChR) with either GTS-21 (partial agonist) or GAT107 (ago-PAM) could inhibit hyperoxia-induced HMGB1 accumulation in the airways and improve innate immunity and clinical outcomes. RAW 264.7 cells, treated with either GTS-21 or GAT107 in the presence of 95% O 2 exhibited decreased levels of HMGB1 in culture media and enhanced phagocytic ability. Hy- peracetylation of nuclear HMGB1 can lead to its release into the extra- cellular milieu and is observed in cells exposed to hyperoxia. Activation of α7nAChR is effective in reducing both hyperoxia-induced HMGB1 accu- mulation and hyperacetylation. To determine whether activation of α7nAChR-mediated macrophage function can be translated into clinical outcomes, mice were exposed to 499% O 2 for 3 d with GTS-21 treatment. GTS-21 significantly decreased both the accumulation of airway levels and hyperacetylation of HMGB1, protein content and neutrophil infiltration. Therefore, α7nAChRs represent a possible pharmacological target for the treatment of HALI in patients receiving MV. E-mail address: alex.gauthier15@stjohns.edu http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.292 P-146 Effects of paraquat in the reproductive function and on redox state of adult male rats Eduardo Benedetti Parisotto, Nícolas Gabriel Martins Silva, Carolinne Sayury Wajima, Barbara Rahn, Juliana Tonietto Domingues, Vitória Hayduck Cenci, Patrícia Acordi Cesconetto, Daiane Cattani, Carla Elise Heinz Rieg, Alessandra Hellbrugge, Karina Bettega Felipe, Rozangela Curi Pedrosa, Ariane Zamoner Depto. de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis-SC, Brasil; Depto. de Análises Clínicas, Universidade Federal do Paraná, Paraná, Curitiba-PR, Brasil A. Stepanova et al. / Free Radical Biology and Medicine 120 (2018) S45–S166 S88