TY  - JOUR
AU  - Korać Jačić, Jelena
AU  - Nikolić, Ljiljana
AU  - Stanković, Dalibor M.
AU  - Opačić, Miloš
AU  - Dimitrijević, Milena S.
AU  - Savić, Danijela
AU  - Grgurić-Šipka, Sanja
AU  - Spasojević, Ivan
AU  - Bogdanović-Pristov, Jelena
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8801
AB  - Upon release in response to stress, epinephrine (Epi) may interact with labile iron pool in human plasma with potentially important (patho)physiological consequences. We have shown that Epi and Fe3+ build stable 1:1 high-spin bidentate complex at physiological pH, and that Epi does not undergo degradation in the presence of iron. However, the interactions of Epi with the more soluble Fe2+, and the impact of iron on biological activity of Epi are still not known. Herein we showed that Epi and Fe2+ build colorless complex which is stable under anaerobic conditions. In the presence of O2, Epi promoted the oxidation of Fe2+ and the formation of Epi-Fe3+ complex. Cyclic voltammetry showed that mid-point potential of Epi-Fe2+ complex is very low (-582 mV vs. standard hydrogen electrode), which explains catalyzed oxidation of Fe2+. Next, we examined the impact of iron binding on biological performance of Epi using patch clamping in cell culture with constitutive expression of adrenergic receptors. Epi alone evoked an increase of outward currents, whereas Epi in the complex with Fe3+ did not. This implies that the binding of Epi to adrenergic receptors and their activation is prevented by the formation of complex with iron. Pro-oxidative activity of Epi-Fe2+ complex may represent a link between chronic stress and cardiovascular problems. On the other hand, labile iron could serve as a modulator of biological activity of ligands. Such interactions may be important in human pathologies that are related to iron overload or deficiency.
T2  - Free Radical Biology and Medicine
T1  - Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors.
VL  - 148
SP  - 123
EP  - 127
DO  - 10.1016/j.freeradbiomed.2020.01.001
ER  - 

@article{
author = "Korać Jačić, Jelena and Nikolić, Ljiljana and Stanković, Dalibor M. and Opačić, Miloš and Dimitrijević, Milena S. and Savić, Danijela and Grgurić-Šipka, Sanja and Spasojević, Ivan and Bogdanović-Pristov, Jelena",
year = "2020",
abstract = "Upon release in response to stress, epinephrine (Epi) may interact with labile iron pool in human plasma with potentially important (patho)physiological consequences. We have shown that Epi and Fe3+ build stable 1:1 high-spin bidentate complex at physiological pH, and that Epi does not undergo degradation in the presence of iron. However, the interactions of Epi with the more soluble Fe2+, and the impact of iron on biological activity of Epi are still not known. Herein we showed that Epi and Fe2+ build colorless complex which is stable under anaerobic conditions. In the presence of O2, Epi promoted the oxidation of Fe2+ and the formation of Epi-Fe3+ complex. Cyclic voltammetry showed that mid-point potential of Epi-Fe2+ complex is very low (-582 mV vs. standard hydrogen electrode), which explains catalyzed oxidation of Fe2+. Next, we examined the impact of iron binding on biological performance of Epi using patch clamping in cell culture with constitutive expression of adrenergic receptors. Epi alone evoked an increase of outward currents, whereas Epi in the complex with Fe3+ did not. This implies that the binding of Epi to adrenergic receptors and their activation is prevented by the formation of complex with iron. Pro-oxidative activity of Epi-Fe2+ complex may represent a link between chronic stress and cardiovascular problems. On the other hand, labile iron could serve as a modulator of biological activity of ligands. Such interactions may be important in human pathologies that are related to iron overload or deficiency.",
journal = "Free Radical Biology and Medicine",
title = "Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors.",
volume = "148",
pages = "123-127",
doi = "10.1016/j.freeradbiomed.2020.01.001"
}

Korać Jačić, J., Nikolić, L., Stanković, D. M., Opačić, M., Dimitrijević, M. S., Savić, D., Grgurić-Šipka, S., Spasojević, I.,& Bogdanović-Pristov, J.. (2020). Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors.. in Free Radical Biology and Medicine, 148, 123-127.
https://doi.org/10.1016/j.freeradbiomed.2020.01.001

Korać Jačić J, Nikolić L, Stanković DM, Opačić M, Dimitrijević MS, Savić D, Grgurić-Šipka S, Spasojević I, Bogdanović-Pristov J. Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors.. in Free Radical Biology and Medicine. 2020;148:123-127.
doi:10.1016/j.freeradbiomed.2020.01.001 .

Korać Jačić, Jelena, Nikolić, Ljiljana, Stanković, Dalibor M., Opačić, Miloš, Dimitrijević, Milena S., Savić, Danijela, Grgurić-Šipka, Sanja, Spasojević, Ivan, Bogdanović-Pristov, Jelena, "Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors." in Free Radical Biology and Medicine, 148 (2020):123-127,
https://doi.org/10.1016/j.freeradbiomed.2020.01.001 . .

TY  - JOUR
AU  - Korać, Jelena
AU  - Stanković, Dalibor M.
AU  - Stanić, Marina
AU  - Bajuk-Bogdanović, Danica V.
AU  - Žižić, Milan
AU  - Bogdanović-Pristov, Jelena
AU  - Grgurić-Šipka, Sanja
AU  - Popović-Bijelić, Ana D.
AU  - Spasojević, Ivan
PY  - 2018
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7582
AB  - Coordinate and redox interactions of epinephrine (Epi) with iron at physiological pH are essential for understanding two very different phenomena - the detrimental effects of chronic stress on the cardiovascular system and the cross-linking of catecholamine-rich biopolymers and frameworks. Here we show that Epi and Fe3+ form stable high-spin complexes in the 1:1 or 3:1 stoichiometry, depending on the Epi/Fe3+ concentration ratio (low or high). Oxygen atoms on the catechol ring represent the sites of coordinate bond formation within physiologically relevant bidentate 1:1 complex. Redox properties of Epi are slightly impacted by Fe3+. On the other hand, Epi and Fe2+ form a complex that acts as a strong reducing agent, which leads to the production of hydrogen peroxide via O-2 reduction, and to a facilitated formation of the Epi-Fe3+ complexes. Epi is not oxidized in this process, i.e. Fe2+ is not an electron shuttle, but the electron donor. Epi-catalyzed oxidation of Fe2+ represents a plausible chemical basis of stress-related damage to heart cells. In addition, our results support the previous findings on the interactions of catecholamine moieties in polymers with iron and provide a novel strategy for improving the efficiency of cross-linking.
T2  - Scientific Reports
T1  - Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH
VL  - 8
SP  - 3530
DO  - 10.1038/s41598-018-21940-7
ER  - 

@article{
author = "Korać, Jelena and Stanković, Dalibor M. and Stanić, Marina and Bajuk-Bogdanović, Danica V. and Žižić, Milan and Bogdanović-Pristov, Jelena and Grgurić-Šipka, Sanja and Popović-Bijelić, Ana D. and Spasojević, Ivan",
year = "2018",
abstract = "Coordinate and redox interactions of epinephrine (Epi) with iron at physiological pH are essential for understanding two very different phenomena - the detrimental effects of chronic stress on the cardiovascular system and the cross-linking of catecholamine-rich biopolymers and frameworks. Here we show that Epi and Fe3+ form stable high-spin complexes in the 1:1 or 3:1 stoichiometry, depending on the Epi/Fe3+ concentration ratio (low or high). Oxygen atoms on the catechol ring represent the sites of coordinate bond formation within physiologically relevant bidentate 1:1 complex. Redox properties of Epi are slightly impacted by Fe3+. On the other hand, Epi and Fe2+ form a complex that acts as a strong reducing agent, which leads to the production of hydrogen peroxide via O-2 reduction, and to a facilitated formation of the Epi-Fe3+ complexes. Epi is not oxidized in this process, i.e. Fe2+ is not an electron shuttle, but the electron donor. Epi-catalyzed oxidation of Fe2+ represents a plausible chemical basis of stress-related damage to heart cells. In addition, our results support the previous findings on the interactions of catecholamine moieties in polymers with iron and provide a novel strategy for improving the efficiency of cross-linking.",
journal = "Scientific Reports",
title = "Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH",
volume = "8",
pages = "3530",
doi = "10.1038/s41598-018-21940-7"
}

Korać, J., Stanković, D. M., Stanić, M., Bajuk-Bogdanović, D. V., Žižić, M., Bogdanović-Pristov, J., Grgurić-Šipka, S., Popović-Bijelić, A. D.,& Spasojević, I.. (2018). Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH. in Scientific Reports, 8, 3530.
https://doi.org/10.1038/s41598-018-21940-7

Korać J, Stanković DM, Stanić M, Bajuk-Bogdanović DV, Žižić M, Bogdanović-Pristov J, Grgurić-Šipka S, Popović-Bijelić AD, Spasojević I. Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH. in Scientific Reports. 2018;8:3530.
doi:10.1038/s41598-018-21940-7 .

Korać, Jelena, Stanković, Dalibor M., Stanić, Marina, Bajuk-Bogdanović, Danica V., Žižić, Milan, Bogdanović-Pristov, Jelena, Grgurić-Šipka, Sanja, Popović-Bijelić, Ana D., Spasojević, Ivan, "Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH" in Scientific Reports, 8 (2018):3530,
https://doi.org/10.1038/s41598-018-21940-7 . .

TY  - JOUR
AU  - Božić, Bojana
AU  - Korać, Jelena
AU  - Stanković, Dalibor M.
AU  - Stanić, Marina
AU  - Romanović, Mima Č.
AU  - Bogdanović-Pristov, Jelena
AU  - Spasić, Snežana D.
AU  - Popović-Bijelić, Ana D.
AU  - Spasojević, Ivan
AU  - Bajčetić, Milica
PY  - 2018
UR  - https://linkinghub.elsevier.com/retrieve/pii/S0891584918311213
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7896
AB  - An increase in the copper pool in body fluids has been related to a number of pathological conditions, including infections. Copper ions may affect antibiotics via the formation of coordination bonds and/or redox reactions. Herein, we analyzed the interactions of Cu2+ with eight β-lactam antibiotics using UV–Vis spectrophotometry, EPR spectroscopy, and electrochemical methods. Penicillin G did not show any detectable interactions with Cu2+. Ampicillin, amoxicillin and cephalexin formed stable colored complexes with octahedral coordination environment of Cu2+ with tetragonal distortion, and primary amine group as the site of coordinate bond formation. These β-lactams increased the solubility of Cu2+ in the phosphate buffer. Ceftazidime and Cu2+ formed a complex with a similar geometry and gave rise to an organic radical. Ceftriaxone-Cu2+ complex appears to exhibit different geometry. All complexes showed 1:1 stoichiometry. Cefaclor reduced Cu2+ to Cu1+ that further reacted with molecular oxygen to produce hydrogen peroxide. Finally, meropenem underwent degradation in the presence of copper. The analysis of activity against Escherichia coli and Staphylococcus aureus showed that the effects of meropenem, amoxicillin, ampicillin, and ceftriaxone were significantly hindered in the presence of copper ions. The interactions with copper ions should be taken into account regarding the problem of antibiotic resistance and in the selection of the most efficient antimicrobial therapy for patients with altered copper homeostasis. © 2018 Elsevier Inc.
T2  - Free Radical Biology and Medicine
T1  - Coordination and redox interactions of β-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity
VL  - 129
SP  - 279
EP  - 285
DO  - 10.1016/j.freeradbiomed.2018.09.038
ER  - 

@article{
author = "Božić, Bojana and Korać, Jelena and Stanković, Dalibor M. and Stanić, Marina and Romanović, Mima Č. and Bogdanović-Pristov, Jelena and Spasić, Snežana D. and Popović-Bijelić, Ana D. and Spasojević, Ivan and Bajčetić, Milica",
year = "2018",
abstract = "An increase in the copper pool in body fluids has been related to a number of pathological conditions, including infections. Copper ions may affect antibiotics via the formation of coordination bonds and/or redox reactions. Herein, we analyzed the interactions of Cu2+ with eight β-lactam antibiotics using UV–Vis spectrophotometry, EPR spectroscopy, and electrochemical methods. Penicillin G did not show any detectable interactions with Cu2+. Ampicillin, amoxicillin and cephalexin formed stable colored complexes with octahedral coordination environment of Cu2+ with tetragonal distortion, and primary amine group as the site of coordinate bond formation. These β-lactams increased the solubility of Cu2+ in the phosphate buffer. Ceftazidime and Cu2+ formed a complex with a similar geometry and gave rise to an organic radical. Ceftriaxone-Cu2+ complex appears to exhibit different geometry. All complexes showed 1:1 stoichiometry. Cefaclor reduced Cu2+ to Cu1+ that further reacted with molecular oxygen to produce hydrogen peroxide. Finally, meropenem underwent degradation in the presence of copper. The analysis of activity against Escherichia coli and Staphylococcus aureus showed that the effects of meropenem, amoxicillin, ampicillin, and ceftriaxone were significantly hindered in the presence of copper ions. The interactions with copper ions should be taken into account regarding the problem of antibiotic resistance and in the selection of the most efficient antimicrobial therapy for patients with altered copper homeostasis. © 2018 Elsevier Inc.",
journal = "Free Radical Biology and Medicine",
title = "Coordination and redox interactions of β-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity",
volume = "129",
pages = "279-285",
doi = "10.1016/j.freeradbiomed.2018.09.038"
}

Božić, B., Korać, J., Stanković, D. M., Stanić, M., Romanović, M. Č., Bogdanović-Pristov, J., Spasić, S. D., Popović-Bijelić, A. D., Spasojević, I.,& Bajčetić, M.. (2018). Coordination and redox interactions of β-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity. in Free Radical Biology and Medicine, 129, 279-285.
https://doi.org/10.1016/j.freeradbiomed.2018.09.038

Božić B, Korać J, Stanković DM, Stanić M, Romanović MČ, Bogdanović-Pristov J, Spasić SD, Popović-Bijelić AD, Spasojević I, Bajčetić M. Coordination and redox interactions of β-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity. in Free Radical Biology and Medicine. 2018;129:279-285.
doi:10.1016/j.freeradbiomed.2018.09.038 .

Božić, Bojana, Korać, Jelena, Stanković, Dalibor M., Stanić, Marina, Romanović, Mima Č., Bogdanović-Pristov, Jelena, Spasić, Snežana D., Popović-Bijelić, Ana D., Spasojević, Ivan, Bajčetić, Milica, "Coordination and redox interactions of β-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity" in Free Radical Biology and Medicine, 129 (2018):279-285,
https://doi.org/10.1016/j.freeradbiomed.2018.09.038 . .

TY  - JOUR
AU  - Božić, Bojana
AU  - Korać, Jelena
AU  - Stanković, Dalibor M.
AU  - Stanić, Marina
AU  - Popović-Bijelić, Ana D.
AU  - Bogdanović-Pristov, Jelena
AU  - Spasojević, Ivan
AU  - Bajčetić, Milica
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1878
AB  - Toxic effects of unconjugated bilirubin (BR) in neonatal hyperbilirubinemia have been related to redox and/or coordinate interactions with Cu2+. However, the development and mechanisms of such interactions at physiological pH have not been resolved. This study shows that BR reduces Cu2+ to Cu1+ in 1:1 stoichiometry. Apparently, BR undergoes degradation, i.e. BR and Cu2+ do not form stable complexes. The binding of Cu2+ to inorganic phosphates, liposomal phosphate groups, or to chelating drug penicillamine, impedes redox interactions with BR. Cu1+ undergoes spontaneous oxidation by O-2 resulting in hydrogen peroxide accumulation and hydroxyl radical production. In relation to this, copper and BR induced synergistic oxidative/damaging effects on erythrocytes membrane, which were alleviated by penicillamine. The production of reactive oxygen species by BR and copper represents a plausible cause of BR toxic effects and cell damage in hyperbilirubinemia. Further examination of therapeutic potentials of copper chelators in the treatment of severe neonatal hyperbilirubinemia is needed.
T2  - Chemico-Biological Interactions
T1  - Mechanisms of redox interactions of bilirubin with copper and the effects of penicillamine
VL  - 278
SP  - 129
EP  - 134
DO  - 10.1016/j.cbi.2017.10.022
ER  - 

@article{
author = "Božić, Bojana and Korać, Jelena and Stanković, Dalibor M. and Stanić, Marina and Popović-Bijelić, Ana D. and Bogdanović-Pristov, Jelena and Spasojević, Ivan and Bajčetić, Milica",
year = "2017",
abstract = "Toxic effects of unconjugated bilirubin (BR) in neonatal hyperbilirubinemia have been related to redox and/or coordinate interactions with Cu2+. However, the development and mechanisms of such interactions at physiological pH have not been resolved. This study shows that BR reduces Cu2+ to Cu1+ in 1:1 stoichiometry. Apparently, BR undergoes degradation, i.e. BR and Cu2+ do not form stable complexes. The binding of Cu2+ to inorganic phosphates, liposomal phosphate groups, or to chelating drug penicillamine, impedes redox interactions with BR. Cu1+ undergoes spontaneous oxidation by O-2 resulting in hydrogen peroxide accumulation and hydroxyl radical production. In relation to this, copper and BR induced synergistic oxidative/damaging effects on erythrocytes membrane, which were alleviated by penicillamine. The production of reactive oxygen species by BR and copper represents a plausible cause of BR toxic effects and cell damage in hyperbilirubinemia. Further examination of therapeutic potentials of copper chelators in the treatment of severe neonatal hyperbilirubinemia is needed.",
journal = "Chemico-Biological Interactions",
title = "Mechanisms of redox interactions of bilirubin with copper and the effects of penicillamine",
volume = "278",
pages = "129-134",
doi = "10.1016/j.cbi.2017.10.022"
}

Božić, B., Korać, J., Stanković, D. M., Stanić, M., Popović-Bijelić, A. D., Bogdanović-Pristov, J., Spasojević, I.,& Bajčetić, M.. (2017). Mechanisms of redox interactions of bilirubin with copper and the effects of penicillamine. in Chemico-Biological Interactions, 278, 129-134.
https://doi.org/10.1016/j.cbi.2017.10.022

Božić B, Korać J, Stanković DM, Stanić M, Popović-Bijelić AD, Bogdanović-Pristov J, Spasojević I, Bajčetić M. Mechanisms of redox interactions of bilirubin with copper and the effects of penicillamine. in Chemico-Biological Interactions. 2017;278:129-134.
doi:10.1016/j.cbi.2017.10.022 .

Božić, Bojana, Korać, Jelena, Stanković, Dalibor M., Stanić, Marina, Popović-Bijelić, Ana D., Bogdanović-Pristov, Jelena, Spasojević, Ivan, Bajčetić, Milica, "Mechanisms of redox interactions of bilirubin with copper and the effects of penicillamine" in Chemico-Biological Interactions, 278 (2017):129-134,
https://doi.org/10.1016/j.cbi.2017.10.022 . .