Horizontal transfer of mitochondria and dihydroorotate ...

A. Stepanova et al. / Free Radical Biology and Medicine 120 (2018) S45–S166

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Oxidazed proteins in blood of patients with nephropathies of various origins Larissa Muravlyova, Vilen Molotov-Luchanskiy, Ryszhan Bakirova, Dmitriy Klyuvev, Ludmila Demidchik, Dinara Omertayeva, Valentina Lee, Irina Beinikova

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deficiency in inducing oxidative stress resulting from acrolein-induced disruption of mitochondrial redox status in the lung.

E-mail address: [email protected] http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.175

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Karaganda State Medical University, Karaganda, Kazakhstan

Unbiased identification of anthracycline-mediated disease protection mechanisms The main purpose of our study was to investigate the oxidative modifications of proteins in blood of patients with nephropathies of various origins. There were 80 patients divided into 4 groups depending on the type of nephropathy. 1st group was represented by patients with acute alcoholic nephropathy; the 2nd group - by patients with nephropathy caused by acute poisoning with alcohol surrogates; in the 3th group pregnant women with gestosis were included; the 4th group – was represented by patients with acute medication nephropathy (acute drug poisoning). The control group consisted of 15 healthy subjects. The reactive protein carbonyl derivatives were detected in plasma and erythrocytes (Levine et.al, 1990), advanced oxidation protein products (AOPP) were detected in serum (Witko-Sarsat et al., 1996). In blood plasma of patients of 1–4 groups the concentration of reactive protein carbonyl derivatives was lower in comparison with control ones (po 0.001). AOPP level was highest in serum of 1-st group patients (po 0.001). In erythrocytes of patients of 1–3 groups the reactive protein carbonyl derivatives were increased (p o0.01). Our results demonstrated that in blood of patients the patterns of oxidized proteins to be varied depending on the type of nephropathy.


Dora Pedroso, Ana Neves-Costa, André Barros, Luis F Moita Instituto Gulbenkian de Ciência, Oeiras, Portugal

Anthracyclines, a class of chemotherapeutic drugs that includes epirubicin, doxorubicin and daunorubicin, induce inflammatory cytokines in an in vitro model of inflammation. In vivo, these drugs are strongly protective in the cecal ligation and puncture (CLP) mouse model of sepsis. Moreover, the DNA damage effector kinase Ataxia Telangiectasia Mutated (ATM) was shown to be activated during anthracycline-mediated protection, which suggested that DNA damage response (DDR) mechanisms are required for disease protection. To identify mechanisms whereby anthracyclines mediate cellular protection we performed RNA sequencing (RNAseq) in immune-responsive primary cells (mouse bone marrow-derived macrophages) stimulated with a pro-inflammatory stimulus. We compared cells pre-treated with two members of the anthracycline family that differed in their capacity to generate DNA damage; we also included etoposide, a DNA damaging drug that, unlike anthracyclines, also generates reactive oxygen species (ROS). An expression profile associated with anthracycline treatment in inflammation was identified and pointed to an NF-kb signature. Other unbiased approaches are currently being explored, including RNAseq in target organs of sepsis and whole genome in vivo targeting of infected model organisms.

E-mail address: [email protected] P-28 http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.176

Idh2 deficiency exacerbates acrolein-induced lung injury through mitochondrial redox environment deterioration P-30 Jung Hyun Park, Hyeong Jun Ku, Jin Hyup Lee, Jeen-Woo Park Kyungpook National University, Daegu, Republic of Korea

Acrolein is known to be involved in acute lung injury and other pulmonary diseases. A number of studies have suggested that acrolein-induced toxic effects are associated with depletion of antioxidants and production of reactive oxygen species. Mitochondrial NADP þ-dependent isocitrate dehydrogenase (IDH2) regulates mitochondrial redox balance and reduces oxidative stress-induced cell injury via generation of NADPH. Therefore, we evaluated the role of IDH2 in acrolein-induced lung injury using idh2 short hairpin RNA (shRNA)-transfected Lewis lung carcinoma (LLC) cells and idh2-deficient (idh2–/–) mice. Downregulation of idh2 expression increased susceptibility to acrolein via induction of apoptotic cell death due to elevated mitochondrial oxidative stress. Idh2 deficiency also promoted acrolein-induced lung injury in idh2 knockout mice through the disruption of mitochondrial redox status. In conclusion, idh2 deficiency leads to mitochondrial redox environment deterioration, which causes acrolein-mediated apoptosis of LLC cells and acrolein-induced lung injury in idh2–/– mice. The present study supports the central role of idh2

Horizontal transfer of mitochondria and dihydroorotate dehydrogenase function in respiration recovery of mtDNA deficient cancer cells Lan-Feng Dong 1, Jaromira Kovarova 2, Martina Bajzikova 2, Ana Coelho 2, Stepana Boukalova 2, Jakub Rohlena 2, Michael V. Berridge 3, Jiri Neuzil 1,2 1

School of Medical Science, Griffith University, Southport, Qld, Australia 2 Institute of Biotechnology, Czech Academy of Sciences, Prague, Czech Republic 3 Malaghan Institute of Medical Research, Wellington, New Zealand

Recently, we showed that ρ0 cancer cells devoid of mitochondrial DNA (mtDNA) recover tumour formation ability only after acquisition of host mtDNA. In order to restore respiration, mtDNA moves between cells in whole

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A. Stepanova et al. / Free Radical Biology and Medicine 120 (2018) S45–S166

mitochondria. While it is now clear that recovery respiration is essential for tumour formation, its functional link to the process is unclear. It includes gradual increase in mtDNA level of homoplasmic host polymorphism, followed by binding of mtDNA-processing enzymes to its regulatory domain, replication and transcription of mtDNA, increased expression of components of respiratory complexes, resulting in full restoration of respiration. We found that pyrimidine biosynthesis, supported by the respiration-linked enzyme dihydroorotate dehydrogenase (DHODH), is critically required to overcome cell cycle arrest. We further confirmed that efficient de novo pyrimidine synthesis, necessary for tumour cell proliferation, is the key event for triggering tumour growth. Moreover, respiration recovery, which is necessary for tumour formation, is associated with efficient de novo pyrimidine synthesis. In conclusion, we propose that DHODH is a critical link between de novo pyrimidine synthesis and respiration, and that it is a promising target for broad-spectrum cancer therapy.

E-mail address: l.dong@griffith.edu.au http://dx.doi.org/10.1016/j.freeradbiomed.2018.04.177

lead to the appearance of biochemical markers of cell death compatible with MPT-driven necrosis


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The tumor environment stabilizes c-Myc oncoprotein through its sustained phosphorylation at serine 62, which promotes its oncogenic activity Deepika Raman 1, Shazib Pervaiz 1,2,3 1

National University of Singapore, Singapore National University Cancer Institute, Singapore 3 NUS Graduate School for Integrative Sciences and Engineering, Singapore 2

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Impact of peroxynitrite-mediated nitrosative stress on human sperm cells Pamela Uribe 1,2, Juana V. Villegas 2,3, María E. Cabrillana 4,5, Rodrigo Boguen 3, Raúl Sánchez 1,6, Miguel W. Fornés 4,5, Vladimir Isachenko 7, Evgenia Isachenko 7 1

Center of Excellence in Translational Medicine, Universidad de La Frontera, Temuco, Chile 2 Department of Internal Medicine, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile 3 Center of Reproductive Biotechnology - Scientific and Technological Bioresource Nucleus (CEBIOR – BIOREN), Universidad de La Frontera, Temuco, Chile 4 Laboratory of Andrology Research of Mendoza (LIAM) Institute of Histology and Embriology of Mendoza (IHEM) Histology and Embryology Area, Department of Morphology and Physiology, School of Medicine, National University of Cuyo & CCT-Mendoza, CONICET, Mendoza, Argentina 5 Research Institute (CIUDA), Medicine Faculty, Universidad del Aconcagua. Mendoza, Argentina 6 Department of Preclinical Sciences, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile 7 Research Group for Reproductive Medicine, Cologne University, Cologne, Germany

We have previously demonstrated that redox homeostasis is governed by two key ROS – superoxide anion (O2-) and hydrogen peroxide (H2O2). Tilting the balance to O2- contributes to engaging cancers onto a prosurvival trajectory. Here, we present a singular event wherein redox modulation of c-Myc attributes cancer cells with survival advantages and elevates their chemoresistance potential. Phosphorylation of c-Myc correlates with its stabilization in cancers. While S62 phosphorylation increases c-Myc stability, T58 phosphorylation destabilizes it. Of particular interest is phosphatase PP2A, as we have shown that it is amenable to redox insults. We have now elucidated that B56α regulatory subunit of PP2A is amenable to redox modification preventing interaction of c-Myc bound B56α with PP2A-AC core enzyme. As assembly of PP2A holoenzyme is disrupted, c-Myc remains phosphorylated at S62. Hyperphosphorylated c-Myc cannot be recognized and engaged by the proteasome leading to increased protein stability and a moderate rise in activation of c-Myc targets. Thus, we have established a novel mechanism wherein the balance between O2-:H2O2 ratio stimulates a pro-survival milieu and reinforces chemoresistance through redox modification of PP2A-B56α, consequentially resulting in stabilization of c-Myc.


P-33 Nitrosative stress is caused by high levels of reactive nitrogen species (RNS) and among the most toxic RNS is peroxynitrite. In infertile men there is an association between high levels of peroxynitrite and decreased sperm quality; however, less is known about the specific cellular impairment caused by peroxynitrite in sperm cells. The aim here was to characterize the in vitro effect of peroxynitrite on human sperm. For this, spermatozoa were exposed to 3-morpholinosydnonimine, a compound that generates peroxynitrite, and several parameters of sperm quality and biochemical markers of cell death were assessed. Untreated sperm were included as controls. At early incubation times peroxynitrite exposure caused a decrease in mitochondrial membrane potential, ATP level and motility while thiol oxidation and tyrosine nitration increased. At prolonged incubation time viability decreased and DNA oxidation, DNA fragmentation and ultrastructural damage increased. Mitochondrial permeability transition (MPT) was induced while caspase activation and phosphatidylserine externalization were not evidenced. These results indicate that peroxynitrite exposure impairs sperm function and ultrastructure and

The comparison of vitamin E and vitamin C levels in type 2 diabetic patients under monotherapy Ayse C. Hamamcioglu 1, Zehra Safi-Oz 2, Yasin Hazer 3, Taner Bayraktaroglu 4 1

Biochemistry Department, Faculty of Pharmacy, Bulent Ecevit University, Zonguldak, Turkey 2 Medical Biology Department, Faculty of Medicine, Bulent Ecevit University, Zonguldak, Turkey 3 Pharmaceutical Botany Department, Faculty of Pharmacy, Bulent Ecevit University, Zonguldak, Turkey 4 Endocrinology and Metabolism Department, Faculty of Medicine, Bulent Ecevit University, Zonguldak, Turkey