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A. Stepanova et al. / Free Radical Biology and Medicine 120 (2018) S45–S166 without modulated TRP14 levels. Our preliminary results suggest that TRP14 is an unusual member of the Trx system, in that TRP14 may act as a repressor of NRF2, modulate HIF activation under hypoxia as well as acting as a weak repressor of NFκB activation. Further analyses are needed to fully evaluate the pTRAF readout also including additional methodologies Our results point towards the role of TRP14 as a dedicated fine-tuning modulator of redox regulated signaling pathways. E-mail address: belen.espinosa@ki.se http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.153 P-7 Reactive Oxygen Species Generating Photosynthesized Ferromagnetic Iron Oxide Nanoparticle as Promising Anti-Leishmanial Agent Akhtar Nadhman 1, Qurat-ul-Ain 2, Amna Munawar 2, Masoom Yasinzai 2 1 Institute of Integrative Biosciences, CECOS University of IT and Emerging Sciences, Peshawar, Pakistan 2 Sulaiman Bin Abdullah Aba Al Khail Centre for Interdisciplinary Research in Basic Sciences, International Islamic University, Islamabad, Pakistan S47 1 Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark 2 Department of Food Science, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark Oxidation of dairy products, and especially infant formulas (IFs), is a major concern to the dairy industry and consumers. Thermal treatment is required for microbiological safety but may contribute to oxidative damage. Such modification may be a health risk for infants with IF as the sole source of nutrition. This study quantifies the extent of modification in commercial IFs. Protein modification in commercial IFs was examined by multiple analytical techniques. Aggregated proteins containing both reducible (disulfide) and non-reducible (di-tyrosine, lanthionine and lysinoalanine) cross-links were detected. Protein carbonyls (o 3.3 nmoles mg-1 protein) were detected, which mainly present on high-molecular-mass materials. UPLC analysis indicated the presence of oxidation products of phenylalanine (m-tyrosine), tryptophan (N-formylkynurenine, kynurenine and 3-hydroxykynurenine), tyrosine (di-tyrosine) and methionine (methionine sulfoxide), consistent with the loss of parent amino acids, and high levels were present in a hypoallergenic brand. Enantiospecific UPLC analysis showed the presence of (non-natural) D-amino acids. These data indicate that amino acids present in proteins in IFs can be modified during manufacturing, with hydrolyzed IF being particularly prone. E-mail address: alex@sund.ku.dk http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.155 P-9 The current study is based on bio-inspired synthesis of visible light responsive ferromagnetic iron oxide nanoparticles (FIONs) using Trigonella foenum-graecum plant and its efficacy as anti-leishmanial agents. Preliminary findings about time- and dose-dependent effectiveness of FIONs on different biological parameters of Leishmania tropica have been investigated. Synthesized FIONs (40 nm) were found more effective against Leishmania upon 15 minutes exposure to LED light (84 lm/W) thus, generating reactive oxygen species (ROS) in comparison dark conditions. Quantum yield of ROS by FIONs was 0.26. Interestingly, hydroxyl radicals and singlet oxygen were found as main ROS moieties involved in cell death via apoptosis. Anti-leishmanial activity of LED exposed FIONs was maximum after 72 h, with an IC50 of 0.02270.001 and 0.07370.002 jig/ ml on promastigotes and amastigotes respectively. FIONs were found biocompatible on human red blood cells, exhibiting LC50 values of 779732 and 2537721 jig/ml for light and dark conditions respectively. These data suggest that the cell killing ability of FIONs was facilitated via ROS generation and oxidative stress upon excitation in visible light hence, were in accordance with previous findings. E-mail address: nadhman@cecos.edu.pk http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.154 P-8 Characterization and quantification of protein oxidative modifications and amino acid racemization in powdered infant milk formula 1 1 2 Bcl-2 phosphorylation at serine-70 protects cancer cells from ROS-induced DNA damage and cell death by engaging the mitochondrial respiratory system Stephen Jun Fei Chong, Shazib Pervaiz National University of Singapore, Singapore Chemotherapeutics target cancer cells by inducing DNA damage. The mechanism of these drugs in damaging DNA relies partly in the elevation of ROS, which in turn causes DNA oxidation, strand breaks and cell death. Although cancer cells are capable of resisting drug-induced cell death by various protective means, the mechanism that specifically rely on modulating the redox milieu, in favor of survival, is not fully elucidated. We now show that phosphorylation of the anti-apoptotic Bcl2 at Serine70 (S70pBcl2), could alleviate drug-induced DNA damage to prevent cancer cell death. This is due to its ability in preventing drug-induced intracellular ROS production. Mechanistically, S70pBcl2 resulted in a diminished interaction between Bcl2 and cytochrome c oxidase subunit Vα (COX5α), a mitochondrial complex VI subunit, as well as Bcl2-dependent shuttling of COX5α to the mitochondria. This in turn reduces complex IV activity, mitochondrial oxygen consumption and ultimately mitochondrial O2- production. Importantly, the inverse correlation between S70pBcl2 and Bcl2/COX5α interaction as well as DNA damage were recapitulated in clinical lymphomas. These data underscore the oncogenic and antioxidant roles of Bcl2 phosphorylation in protecting cancer cells from DNA damage-induced cell death. E-mail address: phsscjf@nus.edu.sg 2 Zhifei Chen , Fabian Leinisch , Ines Greco , Wei Zhang , Nan Shu 1, Christine Y. Chuang 1, Marianne N. Lund 1,2, Michael J. Davies 1 http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.156