TY  - CONF
AU  - Nikolic, Ljiljana
AU  - Savic, Danijela
AU  - Korać Jačić, Jelena
AU  - Petkovic, Branka
AU  - Stojadinovic, Gordana
AU  - Martac, Ljiljana
AU  - Bogdanović Pristov, Jelena
PY  - 2022
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2010
AB  - Living cells exhibit multiple ion channel proteins and malfunction of these channels underlies 
numerous diseases. Channelopathies include diseases of the nervous, cardiovascular, respiratory, 
endocrine, urinary, and immune system. Currently, ion channels represent the second-largest target for existing drugs. Here, using the whole-cell patch-clamp technique, we explored the epinephrine effect on membrane ionic currents in glioma C6 cells. We demonstrate that epinephrine specifically evokes an increase of C6 cells outward ionic currents that is stable within 10 min, while it does not affect inward currents. Our results thus provide fine resolution and time frame for targeting ion channel activity that is crucial in pharmacological investigations.
PB  - Society of Physical Chemists of Serbia
C3  - PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects  of Physical Chemistry (Proceedings)
T1  - MEMBRANE CURRENTS OF C6 CELLS IN PHARMACOLOGICAL  INVESTIGATION
EP  - 592
SP  - 589
VL  - 2
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2010
ER  - 

@conference{
author = "Nikolic, Ljiljana and Savic, Danijela and Korać Jačić, Jelena and Petkovic, Branka and Stojadinovic, Gordana and Martac, Ljiljana and Bogdanović Pristov, Jelena",
year = "2022",
abstract = "Living cells exhibit multiple ion channel proteins and malfunction of these channels underlies 
numerous diseases. Channelopathies include diseases of the nervous, cardiovascular, respiratory, 
endocrine, urinary, and immune system. Currently, ion channels represent the second-largest target for existing drugs. Here, using the whole-cell patch-clamp technique, we explored the epinephrine effect on membrane ionic currents in glioma C6 cells. We demonstrate that epinephrine specifically evokes an increase of C6 cells outward ionic currents that is stable within 10 min, while it does not affect inward currents. Our results thus provide fine resolution and time frame for targeting ion channel activity that is crucial in pharmacological investigations.",
publisher = "Society of Physical Chemists of Serbia",
journal = "PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects  of Physical Chemistry (Proceedings)",
title = "MEMBRANE CURRENTS OF C6 CELLS IN PHARMACOLOGICAL  INVESTIGATION",
pages = "592-589",
volume = "2",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2010"
}

Nikolic, L., Savic, D., Korać Jačić, J., Petkovic, B., Stojadinovic, G., Martac, L.,& Bogdanović Pristov, J.. (2022). MEMBRANE CURRENTS OF C6 CELLS IN PHARMACOLOGICAL  INVESTIGATION. in PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects  of Physical Chemistry (Proceedings)
Society of Physical Chemists of Serbia., 2, 589-592.
https://hdl.handle.net/21.15107/rcub_rimsi_2010

Nikolic L, Savic D, Korać Jačić J, Petkovic B, Stojadinovic G, Martac L, Bogdanović Pristov J. MEMBRANE CURRENTS OF C6 CELLS IN PHARMACOLOGICAL  INVESTIGATION. in PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects  of Physical Chemistry (Proceedings). 2022;2:589-592.
https://hdl.handle.net/21.15107/rcub_rimsi_2010 .

Nikolic, Ljiljana, Savic, Danijela, Korać Jačić, Jelena, Petkovic, Branka, Stojadinovic, Gordana, Martac, Ljiljana, Bogdanović Pristov, Jelena, "MEMBRANE CURRENTS OF C6 CELLS IN PHARMACOLOGICAL  INVESTIGATION" in PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects  of Physical Chemistry (Proceedings), 2 (2022):589-592,
https://hdl.handle.net/21.15107/rcub_rimsi_2010 .

TY  - JOUR
AU  - Korać Jačić, Jelena
AU  - Nikolić, Ljiljana M.
AU  - Stanković, Dalibor M.
AU  - Opačić, Miloš
AU  - Dimitrijević, Milena
AU  - Savić, Danijela Z
AU  - Grguric-Sipka, Sanja
AU  - Spasojević, Ivan
AU  - Bogdanović Pristov, Jelena
PY  - 2020
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1344
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 O-2, 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.
PB  - Elsevier Science Inc, New York
T2  - Free Radical Biology and Medicine
T1  - Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors
EP  - 127
SP  - 123
VL  - 148
DO  - 10.1016/j.freeradbiomed.2020.01.001
ER  - 

@article{
author = "Korać Jačić, Jelena and Nikolić, Ljiljana M. and Stanković, Dalibor M. and Opačić, Miloš and Dimitrijević, Milena and Savić, Danijela Z and Grguric-Sipka, 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 O-2, 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.",
publisher = "Elsevier Science Inc, New York",
journal = "Free Radical Biology and Medicine",
title = "Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors",
pages = "127-123",
volume = "148",
doi = "10.1016/j.freeradbiomed.2020.01.001"
}

Korać Jačić, J., Nikolić, L. M., Stanković, D. M., Opačić, M., Dimitrijević, M., Savić, D. Z., Grguric-Sipka, 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
Elsevier Science Inc, New York., 148, 123-127.
https://doi.org/10.1016/j.freeradbiomed.2020.01.001

Korać Jačić J, Nikolić LM, Stanković DM, Opačić M, Dimitrijević M, Savić DZ, Grguric-Sipka 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 M., Stanković, Dalibor M., Opačić, Miloš, Dimitrijević, Milena, Savić, Danijela Z, Grguric-Sipka, 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  - CONF
AU  - Bozic Cvijan, Bojana
AU  - Korać Jačić, Jelena
AU  - Stanković, Dalibor
AU  - Stanić, Marina
AU  - Popovic Bijelic, Ana
AU  - Bogdanović Pristov, Jelena
AU  - Spasojević, Ivan
AU  - Bajcetic, Milica
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2847
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 O2 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.
PB  - Srpsko farmakološko društvo Beograd, Novi Sad
C3  - 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation
T1  - Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper
EP  - 242
SP  - 240
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2847
ER  - 

@conference{
author = "Bozic Cvijan, Bojana and Korać Jačić, Jelena and Stanković, Dalibor and Stanić, Marina and Popovic Bijelic, Ana and Bogdanović Pristov, Jelena and Spasojević, Ivan and Bajcetic, Milica",
year = "2019",
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 O2 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.",
publisher = "Srpsko farmakološko društvo Beograd, Novi Sad",
journal = "14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation",
title = "Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper",
pages = "242-240",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2847"
}

Bozic Cvijan, B., Korać Jačić, J., Stanković, D., Stanić, M., Popovic Bijelic, A., Bogdanović Pristov, J., Spasojević, I.,& Bajcetic, M.. (2019). Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper. in 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation
Srpsko farmakološko društvo Beograd, Novi Sad., 240-242.
https://hdl.handle.net/21.15107/rcub_rimsi_2847

Bozic Cvijan B, Korać Jačić J, Stanković D, Stanić M, Popovic Bijelic A, Bogdanović Pristov J, Spasojević I, Bajcetic M. Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper. in 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation. 2019;:240-242.
https://hdl.handle.net/21.15107/rcub_rimsi_2847 .

Bozic Cvijan, Bojana, Korać Jačić, Jelena, Stanković, Dalibor, Stanić, Marina, Popovic Bijelic, Ana, Bogdanović Pristov, Jelena, Spasojević, Ivan, Bajcetic, Milica, "Penicillamine prevents damaging redox in vitro interactions of bilirubin and copper" in 14th Serbian Congress of Farmacologists and 4th Serbian Congress of Clinical Pharmacology with international participation (2019):240-242,
https://hdl.handle.net/21.15107/rcub_rimsi_2847 .

TY  - CONF
AU  - Nikolic, Ljiljana
AU  - Korać Jačić, Jelena
AU  - Bijelic, Dunja
AU  - Spasojević, Ivan
AU  - Bogdanović Pristov, Jelena
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2020
AB  - Iron, an essential element for living organisms, participates in a wide range of metabolic processes. It appears predominantly firmly bound to proteins, but can also be loosely bound to low-affinity ligands, referred as labile iron pool (LIP). The composition and amount of LIP can vary considerably under different physiological conditions, playing a beneficial role in iron economy and homeostasis or contributing to the generation of reactive oxygen species. It is still not known if bioactivity of low-affinity ligands can be modulated by iron binding. Catecholamine neurotransmitters including norepinephrine (NE) can chelate iron. In the close vicinity of synaptic cleft, astrocytes are direct target of norepinephrine. Here we show on cultured rat cortical astrocytes that iron bound to NE completely blocks neurotransmitter activity of NE. However, how astrocyte activity changes when norepinephrine binds iron remains unknown. We show, using spectrophotometry that NE and Fe3+ form complex in the 1:1 stoichiometry, at pH 7.4. Iron effect on astrocyte response to NE was examined by the whole-cell patch-clamp technique. NE alone evokes changes in the membrane currents of astrocytes, but such effects were not observed for the NE- Fe3+ complex. Our results demonstrating that iron in the complex with norepinephrine inhibits alpha-adrenergic receptors and modulates astrocyte activity, imply a novel neuromodulatory role for LIP.
PB  - COST Action CA15133
C3  - Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland
T1  - Iron modulates norepinephrine effect on astrocytes
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2020
ER  - 

@conference{
author = "Nikolic, Ljiljana and Korać Jačić, Jelena and Bijelic, Dunja and Spasojević, Ivan and Bogdanović Pristov, Jelena",
year = "2019",
abstract = "Iron, an essential element for living organisms, participates in a wide range of metabolic processes. It appears predominantly firmly bound to proteins, but can also be loosely bound to low-affinity ligands, referred as labile iron pool (LIP). The composition and amount of LIP can vary considerably under different physiological conditions, playing a beneficial role in iron economy and homeostasis or contributing to the generation of reactive oxygen species. It is still not known if bioactivity of low-affinity ligands can be modulated by iron binding. Catecholamine neurotransmitters including norepinephrine (NE) can chelate iron. In the close vicinity of synaptic cleft, astrocytes are direct target of norepinephrine. Here we show on cultured rat cortical astrocytes that iron bound to NE completely blocks neurotransmitter activity of NE. However, how astrocyte activity changes when norepinephrine binds iron remains unknown. We show, using spectrophotometry that NE and Fe3+ form complex in the 1:1 stoichiometry, at pH 7.4. Iron effect on astrocyte response to NE was examined by the whole-cell patch-clamp technique. NE alone evokes changes in the membrane currents of astrocytes, but such effects were not observed for the NE- Fe3+ complex. Our results demonstrating that iron in the complex with norepinephrine inhibits alpha-adrenergic receptors and modulates astrocyte activity, imply a novel neuromodulatory role for LIP.",
publisher = "COST Action CA15133",
journal = "Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland",
title = "Iron modulates norepinephrine effect on astrocytes",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2020"
}

Nikolic, L., Korać Jačić, J., Bijelic, D., Spasojević, I.,& Bogdanović Pristov, J.. (2019). Iron modulates norepinephrine effect on astrocytes. in Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland
COST Action CA15133..
https://hdl.handle.net/21.15107/rcub_rimsi_2020

Nikolic L, Korać Jačić J, Bijelic D, Spasojević I, Bogdanović Pristov J. Iron modulates norepinephrine effect on astrocytes. in Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland. 2019;.
https://hdl.handle.net/21.15107/rcub_rimsi_2020 .

Nikolic, Ljiljana, Korać Jačić, Jelena, Bijelic, Dunja, Spasojević, Ivan, Bogdanović Pristov, Jelena, "Iron modulates norepinephrine effect on astrocytes" in Book of abstracts: 4th FeSBioNet Meeting: COST Action CA15133; 2019 Sep 16-19; Gdansk, Poland (2019),
https://hdl.handle.net/21.15107/rcub_rimsi_2020 .

TY  - CONF
AU  - Korać Jačić, Jelena
AU  - Nikolic, Ljiljana
AU  - Bijelic, Dunja
AU  - Spasojević, Ivan
AU  - Bogdanović Pristov, Jelena
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2016
AB  - Aims: Astrocyte position between synapses and blood vessels allows them to ful l crucial functions such as regulation of synaptic activity and potassium bu ering. Well positioned in the close vicinity of synaptic cleft astrocytes are considered to be a direct target of norepinephrine (NE). Synaptic activity and neurotransmitter actions can be in uenced by extracellular iron. Here we investigated whether iron interacts with NE and if this interaction can modulate astrocyte response to NE. Methods: To investigate the interaction between iron and norepinephrine we used spectrophotometry approach. Iron e ect on astrocyte response to NE was examined by the whole-cell patch-clamp technique. Membrane currents were recorded from cultured cortical astrocytes prepared from WT rats. Results: Using spectrophotometry we observed that iron interacts with NE which leads to the formation of a stable complex in the 1:1 stoichiometry. We also found that iron bound to NE completely blocks NE-induced increase of large-conductance calcium sensitive potassium current in astrocytes. Conclusions: Astrocyte response to NE is modi ed when this neurotransmitter forms a complex with iron. This implies that NE binding to astrocytic noradrenergic receptors may be prevented by iron. Our ndings point toward compromised astrocyte functions related to the potassium bu ering when NE action is modified by iron.
PB  - Serbian Neuroscience Society, Belgrade
C3  - Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia.
T1  - IRON MODULATES NOREPINEPHRINE EFFECT ON ASTROCYTES
SP  - 370
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2016
ER  - 

@conference{
author = "Korać Jačić, Jelena and Nikolic, Ljiljana and Bijelic, Dunja and Spasojević, Ivan and Bogdanović Pristov, Jelena",
year = "2019",
abstract = "Aims: Astrocyte position between synapses and blood vessels allows them to ful l crucial functions such as regulation of synaptic activity and potassium bu ering. Well positioned in the close vicinity of synaptic cleft astrocytes are considered to be a direct target of norepinephrine (NE). Synaptic activity and neurotransmitter actions can be in uenced by extracellular iron. Here we investigated whether iron interacts with NE and if this interaction can modulate astrocyte response to NE. Methods: To investigate the interaction between iron and norepinephrine we used spectrophotometry approach. Iron e ect on astrocyte response to NE was examined by the whole-cell patch-clamp technique. Membrane currents were recorded from cultured cortical astrocytes prepared from WT rats. Results: Using spectrophotometry we observed that iron interacts with NE which leads to the formation of a stable complex in the 1:1 stoichiometry. We also found that iron bound to NE completely blocks NE-induced increase of large-conductance calcium sensitive potassium current in astrocytes. Conclusions: Astrocyte response to NE is modi ed when this neurotransmitter forms a complex with iron. This implies that NE binding to astrocytic noradrenergic receptors may be prevented by iron. Our ndings point toward compromised astrocyte functions related to the potassium bu ering when NE action is modified by iron.",
publisher = "Serbian Neuroscience Society, Belgrade",
journal = "Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia.",
title = "IRON MODULATES NOREPINEPHRINE EFFECT ON ASTROCYTES",
pages = "370",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2016"
}

Korać Jačić, J., Nikolic, L., Bijelic, D., Spasojević, I.,& Bogdanović Pristov, J.. (2019). IRON MODULATES NOREPINEPHRINE EFFECT ON ASTROCYTES. in Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia.
Serbian Neuroscience Society, Belgrade., 370.
https://hdl.handle.net/21.15107/rcub_rimsi_2016

Korać Jačić J, Nikolic L, Bijelic D, Spasojević I, Bogdanović Pristov J. IRON MODULATES NOREPINEPHRINE EFFECT ON ASTROCYTES. in Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia.. 2019;:370.
https://hdl.handle.net/21.15107/rcub_rimsi_2016 .

Korać Jačić, Jelena, Nikolic, Ljiljana, Bijelic, Dunja, Spasojević, Ivan, Bogdanović Pristov, Jelena, "IRON MODULATES NOREPINEPHRINE EFFECT ON ASTROCYTES" in Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia. (2019):370,
https://hdl.handle.net/21.15107/rcub_rimsi_2016 .

TY  - CONF
AU  - Korać Jačić, Jelena
AU  - Stanković, Dalibor
AU  - Bogdanović Pristov, Jelena
AU  - Nikolic, Ljiljana
AU  - Spasojević, Ivan
PY  - 2018
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2844
AB  - Epinephrine ((R)-4-(1-hydroxy-2-(methylamino)ethyl)-benzene-1,2-diol (Epi) is catecholamine that is released by the sympathetic nervous system and adrenal medulla. It is a physiologically important molecule that acts as a hormone, neurotransmitter, and medication with a broad range of effects 1-3 . Coordinate and redox interaction of Epi with iron affects the interactions with other molecules and its biological effects 4 . In this study, we reported details of redox interactions of Epi with Fe 2+ at pH 7.4, which correspond to the pH value of human plasma Epi and Fe 2+ form a complex that acts as a strong reducing agent. Cyclic voltammetry showed that the positions of E pa and E pc potentials were at approximately -480 and -1100 mV. This implies that Epi and Fe 2+ build a complex with unique redox properties. E1/2 was significantly lower compared to E0' for O 2 /O 2•- (-350 mV). It is important to point out this because superoxide radical anion is produced via spontaneous Fe 2+ reaction with O 2. In other words, Epi-Fe 2+ complex should be capable of reducing transition metals in (patho)physiologicaly relevant complexes that are not susceptible to reduction by O 2. Our results confirmed that Epi-Fe 2+ is capable of reducing the S-S group of glutathione disulfide. On the other hand, Epi acted in a catalyst-like fashion to promote Fe 2+ oxidation by molecular oxygen, and to a facilitated formation of the Epi–Fe 3+ complexes, at physiological pH. In addition, we examined the effects of epinepfrine and Epi/Fe3+ system on glioma cells. Epinephrine alone evokes changes in the membrane currents of glioma cells, but such effects were not observed for the complex with Fe 3+ . This implies that Epi-Fe 3+ might modulate neural activity of Epi in CNS.
PB  - Biohemijsko drustvo Srbije
C3  - Proceedings: Serbian Biochemical Society Eigth Conference with international participation: Coordination in Biochemistry and Life; 2018 Nov 16; Novi Sad, Serbia
T1  - Redox interactions of epinephrine with iron at physiological pH
EP  - 142
SP  - 141
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2844
ER  - 

@conference{
author = "Korać Jačić, Jelena and Stanković, Dalibor and Bogdanović Pristov, Jelena and Nikolic, Ljiljana and Spasojević, Ivan",
year = "2018",
abstract = "Epinephrine ((R)-4-(1-hydroxy-2-(methylamino)ethyl)-benzene-1,2-diol (Epi) is catecholamine that is released by the sympathetic nervous system and adrenal medulla. It is a physiologically important molecule that acts as a hormone, neurotransmitter, and medication with a broad range of effects 1-3 . Coordinate and redox interaction of Epi with iron affects the interactions with other molecules and its biological effects 4 . In this study, we reported details of redox interactions of Epi with Fe 2+ at pH 7.4, which correspond to the pH value of human plasma Epi and Fe 2+ form a complex that acts as a strong reducing agent. Cyclic voltammetry showed that the positions of E pa and E pc potentials were at approximately -480 and -1100 mV. This implies that Epi and Fe 2+ build a complex with unique redox properties. E1/2 was significantly lower compared to E0' for O 2 /O 2•- (-350 mV). It is important to point out this because superoxide radical anion is produced via spontaneous Fe 2+ reaction with O 2. In other words, Epi-Fe 2+ complex should be capable of reducing transition metals in (patho)physiologicaly relevant complexes that are not susceptible to reduction by O 2. Our results confirmed that Epi-Fe 2+ is capable of reducing the S-S group of glutathione disulfide. On the other hand, Epi acted in a catalyst-like fashion to promote Fe 2+ oxidation by molecular oxygen, and to a facilitated formation of the Epi–Fe 3+ complexes, at physiological pH. In addition, we examined the effects of epinepfrine and Epi/Fe3+ system on glioma cells. Epinephrine alone evokes changes in the membrane currents of glioma cells, but such effects were not observed for the complex with Fe 3+ . This implies that Epi-Fe 3+ might modulate neural activity of Epi in CNS.",
publisher = "Biohemijsko drustvo Srbije",
journal = "Proceedings: Serbian Biochemical Society Eigth Conference with international participation: Coordination in Biochemistry and Life; 2018 Nov 16; Novi Sad, Serbia",
title = "Redox interactions of epinephrine with iron at physiological pH",
pages = "142-141",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2844"
}

Korać Jačić, J., Stanković, D., Bogdanović Pristov, J., Nikolic, L.,& Spasojević, I.. (2018). Redox interactions of epinephrine with iron at physiological pH. in Proceedings: Serbian Biochemical Society Eigth Conference with international participation: Coordination in Biochemistry and Life; 2018 Nov 16; Novi Sad, Serbia
Biohemijsko drustvo Srbije., 141-142.
https://hdl.handle.net/21.15107/rcub_rimsi_2844

Korać Jačić J, Stanković D, Bogdanović Pristov J, Nikolic L, Spasojević I. Redox interactions of epinephrine with iron at physiological pH. in Proceedings: Serbian Biochemical Society Eigth Conference with international participation: Coordination in Biochemistry and Life; 2018 Nov 16; Novi Sad, Serbia. 2018;:141-142.
https://hdl.handle.net/21.15107/rcub_rimsi_2844 .

Korać Jačić, Jelena, Stanković, Dalibor, Bogdanović Pristov, Jelena, Nikolic, Ljiljana, Spasojević, Ivan, "Redox interactions of epinephrine with iron at physiological pH" in Proceedings: Serbian Biochemical Society Eigth Conference with international participation: Coordination in Biochemistry and Life; 2018 Nov 16; Novi Sad, Serbia (2018):141-142,
https://hdl.handle.net/21.15107/rcub_rimsi_2844 .

TY  - JOUR
AU  - Korać Jačić, Jelena
AU  - Todorović, Nina
AU  - Zakrzewska, Joanna
AU  - Žižić, Milan
AU  - Spasojević, Ivan
PY  - 2018
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1161
AB  - Epinephrine (Epi) is a physiologically important catecholamine. Molecular conformation of Epi controls the interactions with other molecules and its biological effects. There have been a number of theoretical studies addressing conformation and hydrogen bonding of Epi in different solvents, but experimental data are scarce. Herein, we applied H-1 NMR, H-1-H-1 COSY, H-1-N-15 HSQC, and NOESY to examine and compare the conformation of Epi in polar solvents-dimethyl sulfoxide (DMSO) and water. The main differences were observed for NH2 and CH2 groups. Both showed chemical nonequivalence of protons in DMSO that was not present in water. The analysis of the effects of increasing temperature and solvent substitution on NMR signals showed that one of the protons in amine group forms a strong intramolecular hydrogen bond with aliphatic OH group, which is H-donor in another hydrogen bond with DMSO. NOESY provided data on the spatial positions of protons in the side chain, allowing for 3D model of the structure of Epi in DMSO to be built. In close, Epi molecule forms an additional 5-membered ring that encompasses bifurcate intra-/intermolecular hydrogen bonds, and acquires conformation that resembles the shape of a "scorpion"-the catechol ring representing the body and the side chain being a forward-curved tail. The conformation of Epi in water lacks the intramolecular hydrogen bond and most likely largely depends on hydrogen bonds with water molecules.
PB  - Springer/Plenum Publishers, New York
T2  - Structural Chemistry
T1  - The conformation of epinephrine in polar solvents: an NMR study
EP  - 1541
IS  - 5
SP  - 1533
VL  - 29
DO  - 10.1007/s11224-018-1144-y
ER  - 

@article{
author = "Korać Jačić, Jelena and Todorović, Nina and Zakrzewska, Joanna and Žižić, Milan and Spasojević, Ivan",
year = "2018",
abstract = "Epinephrine (Epi) is a physiologically important catecholamine. Molecular conformation of Epi controls the interactions with other molecules and its biological effects. There have been a number of theoretical studies addressing conformation and hydrogen bonding of Epi in different solvents, but experimental data are scarce. Herein, we applied H-1 NMR, H-1-H-1 COSY, H-1-N-15 HSQC, and NOESY to examine and compare the conformation of Epi in polar solvents-dimethyl sulfoxide (DMSO) and water. The main differences were observed for NH2 and CH2 groups. Both showed chemical nonequivalence of protons in DMSO that was not present in water. The analysis of the effects of increasing temperature and solvent substitution on NMR signals showed that one of the protons in amine group forms a strong intramolecular hydrogen bond with aliphatic OH group, which is H-donor in another hydrogen bond with DMSO. NOESY provided data on the spatial positions of protons in the side chain, allowing for 3D model of the structure of Epi in DMSO to be built. In close, Epi molecule forms an additional 5-membered ring that encompasses bifurcate intra-/intermolecular hydrogen bonds, and acquires conformation that resembles the shape of a "scorpion"-the catechol ring representing the body and the side chain being a forward-curved tail. The conformation of Epi in water lacks the intramolecular hydrogen bond and most likely largely depends on hydrogen bonds with water molecules.",
publisher = "Springer/Plenum Publishers, New York",
journal = "Structural Chemistry",
title = "The conformation of epinephrine in polar solvents: an NMR study",
pages = "1541-1533",
number = "5",
volume = "29",
doi = "10.1007/s11224-018-1144-y"
}

Korać Jačić, J., Todorović, N., Zakrzewska, J., Žižić, M.,& Spasojević, I.. (2018). The conformation of epinephrine in polar solvents: an NMR study. in Structural Chemistry
Springer/Plenum Publishers, New York., 29(5), 1533-1541.
https://doi.org/10.1007/s11224-018-1144-y

Korać Jačić J, Todorović N, Zakrzewska J, Žižić M, Spasojević I. The conformation of epinephrine in polar solvents: an NMR study. in Structural Chemistry. 2018;29(5):1533-1541.
doi:10.1007/s11224-018-1144-y .

Korać Jačić, Jelena, Todorović, Nina, Zakrzewska, Joanna, Žižić, Milan, Spasojević, Ivan, "The conformation of epinephrine in polar solvents: an NMR study" in Structural Chemistry, 29, no. 5 (2018):1533-1541,
https://doi.org/10.1007/s11224-018-1144-y . .

TY  - JOUR
AU  - Korać Jačić, Jelena
AU  - Stanković, Dalibor M.
AU  - Stanić, Marina
AU  - Bajuk-Bogdanović, Danica
AU  - Žižić, Milan
AU  - Bogdanović Pristov, Jelena
AU  - Grguric-Sipka, Sanja
AU  - Popovic-Bijelic, Ana
AU  - Spasojević, Ivan
PY  - 2018
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1138
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.
PB  - Nature Publishing Group, London
T2  - Scientific Reports
T1  - Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH
VL  - 8
DO  - 10.1038/s41598-018-21940-7
ER  - 

@article{
author = "Korać Jačić, Jelena and Stanković, Dalibor M. and Stanić, Marina and Bajuk-Bogdanović, Danica and Žižić, Milan and Bogdanović Pristov, Jelena and Grguric-Sipka, Sanja and Popovic-Bijelic, Ana 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.",
publisher = "Nature Publishing Group, London",
journal = "Scientific Reports",
title = "Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH",
volume = "8",
doi = "10.1038/s41598-018-21940-7"
}

Korać Jačić, J., Stanković, D. M., Stanić, M., Bajuk-Bogdanović, D., Žižić, M., Bogdanović Pristov, J., Grguric-Sipka, S., Popovic-Bijelic, A.,& Spasojević, I.. (2018). Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH. in Scientific Reports
Nature Publishing Group, London., 8.
https://doi.org/10.1038/s41598-018-21940-7

Korać Jačić J, Stanković DM, Stanić M, Bajuk-Bogdanović D, Žižić M, Bogdanović Pristov J, Grguric-Sipka S, Popovic-Bijelic A, Spasojević I. Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH. in Scientific Reports. 2018;8.
doi:10.1038/s41598-018-21940-7 .

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

TY  - JOUR
AU  - Bozic, Bojana
AU  - Korać Jačić, Jelena
AU  - Stanković, Dalibor M.
AU  - Stanić, Marina
AU  - Romanović, Mima
AU  - Bogdanović Pristov, Jelena
AU  - Spasic, Snežana
AU  - Popovic-Bijelic, Ana
AU  - Spasojević, Ivan
AU  - Bajčetić, Milica
PY  - 2018
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1111
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 beta-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 beta-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.
PB  - Elsevier Science Inc, New York
T2  - Free Radical Biology and Medicine
T1  - Coordination and redox interactions of beta-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity
EP  - 285
SP  - 279
VL  - 129
DO  - 10.1016/j.freeradbiomed.2018.09.038
ER  - 

@article{
author = "Bozic, Bojana and Korać Jačić, Jelena and Stanković, Dalibor M. and Stanić, Marina and Romanović, Mima and Bogdanović Pristov, Jelena and Spasic, Snežana and Popovic-Bijelic, Ana 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 beta-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 beta-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.",
publisher = "Elsevier Science Inc, New York",
journal = "Free Radical Biology and Medicine",
title = "Coordination and redox interactions of beta-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity",
pages = "285-279",
volume = "129",
doi = "10.1016/j.freeradbiomed.2018.09.038"
}

Bozic, B., Korać Jačić, J., Stanković, D. M., Stanić, M., Romanović, M., Bogdanović Pristov, J., Spasic, S., Popovic-Bijelic, A., Spasojević, I.,& Bajčetić, M.. (2018). Coordination and redox interactions of beta-lactam antibiotics with Cu2+ in physiological settings and the impact on antibacterial activity. in Free Radical Biology and Medicine
Elsevier Science Inc, New York., 129, 279-285.
https://doi.org/10.1016/j.freeradbiomed.2018.09.038

Bozic B, Korać Jačić J, Stanković DM, Stanić M, Romanović M, Bogdanović Pristov J, Spasic S, Popovic-Bijelic A, Spasojević I, Bajčetić M. Coordination and redox interactions of beta-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 .

Bozic, Bojana, Korać Jačić, Jelena, Stanković, Dalibor M., Stanić, Marina, Romanović, Mima, Bogdanović Pristov, Jelena, Spasic, Snežana, Popovic-Bijelic, Ana, Spasojević, Ivan, Bajčetić, Milica, "Coordination and redox interactions of beta-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  - CONF
AU  - Korać Jačić, Jelena
AU  - Stanković, Dalibor
AU  - Stanić, Marina
AU  - Bajuk-Bogdanovic, Danica
AU  - Žižić, Milan
AU  - Bogdanović Pristov, Jelena
AU  - Popovic Bijelic, Ana
AU  - Spasojević, Ivan
PY  - 2017
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2838
AB  - Adrenaline (Adr) is catecholamine that is released by the sympathetic nervous system and
adrenal medulla. It is involved in several physiological functions, including regulation of
blood pressure, vasoconstriction, cardiac stimulation, and regulation of the blood glucose
levels 1
. Transients of high levels of Adr in the bloodstream have been recognized for a
long time as a cause of cardiovascular problems that develop under chronic exposure to
psychosocial and physical stress 2,3. A number of studies have found a connection between
the excess of Adr, cardiotoxic effects, and oxidative stress, that is irrespective of
adrenergic receptors stimulation 2-4. The mechanism behind this involves Adr (coordinate
and redox) interactions with iron, which are still not clear. Two main concepts have been
proposed - Adr autooxidation and redox interactions with iron, the most abundant
transition metal in human plasma 5
. Fe3+ is known to build complexes with catechols 6
, but
data on Fe3+ coordinate interactions with Adr at physiological pH are missing. In addition
to its (patho)physiological role, Adr is of interest from the aspect of development of
catecholamine-rich biopolymers with adhesive properties and metelloorganic frameworks
7,8. The adhesion and other properties materials are based on the cross-linking via
coordinate bonds with Fe3+ at pH > 7. Finally, ligands might dramatically alter the redox
potential of Fe3+/Fe2+ couple 9
. It has been shown that specific ligands with high affinity
for Fe3+, including some catechols, might promote the oxidation and increase the reactivity
of Fe2+ with molecular oxygen 10.
The aim of our study was to examine the nature of Adr interactions with Fe3+ and Fe2+:
stoichiometry, sites of coordinate bonds formation and structure of complex(es), and redox
activity, at pH 7.4 and different concentration ratios. The coordinate and redox interactions
were investigated using UV/Vis spectrophotometry, low temperature EPR, Raman
143
spectroscopy, cyclic voltammetry, and oximetry. The stability of Adr in the studied
reactions was monitored by HPLC.
At pH 7.4, Adr forms complexes with Fe3+, in the 1:1, and 3:1 stoichiometry, depending on
(high or low) Adr/Fe3+ concentration ratio. The high-spin Fe3+ 1:1 and 3:1 complexes show
different symmetries, with the 3:1 complex displaying higher EPR spectral anisotropy.
Raman spectroscopy showed that oxygen atoms on the catechol ring represent the sites of
coordinate bond formation in the bidentate Adr-Fe3+ complex. The bonds appear to be
stronger in the 1:1 complex, and not to share the same plane with the ring. On the other
hand, Adr and Fe2+ build a complex that acts as a strong reducing agent. In the presence of
O2, this leads to the production of H2O2, and to a facilitated formation of Adr/Fe3+
complexes. Adr is not oxidized in this process, i.e. iron is not an electron shuttle but
electron donor. Catalyzed oxidation of Fe2+ in the presence of Adr represents a plausible
chemical basis of stress-related damage of heart cells. In addition, our results imply that
the application/pre-binding of Fe2+ followed by oxidation at pH > 7 might be a simple
alternative strategy for promotion of cross-linking in catecholamine-rich biopolymers
frameworks.
PB  - Biohemijsko društvo Srbije
C3  - Serbian Biochemical Society, Seventh Conference. "Biochemistry of Control in Life and Technology"
T1  - Ligand and redox - interactions of adrenaline with iron at physiological pH
EP  - 144
SP  - 143
UR  - https://hdl.handle.net/21.15107/rcub_rimsi_2838
ER  - 

@conference{
author = "Korać Jačić, Jelena and Stanković, Dalibor and Stanić, Marina and Bajuk-Bogdanovic, Danica and Žižić, Milan and Bogdanović Pristov, Jelena and Popovic Bijelic, Ana and Spasojević, Ivan",
year = "2017",
abstract = "Adrenaline (Adr) is catecholamine that is released by the sympathetic nervous system and
adrenal medulla. It is involved in several physiological functions, including regulation of
blood pressure, vasoconstriction, cardiac stimulation, and regulation of the blood glucose
levels 1
. Transients of high levels of Adr in the bloodstream have been recognized for a
long time as a cause of cardiovascular problems that develop under chronic exposure to
psychosocial and physical stress 2,3. A number of studies have found a connection between
the excess of Adr, cardiotoxic effects, and oxidative stress, that is irrespective of
adrenergic receptors stimulation 2-4. The mechanism behind this involves Adr (coordinate
and redox) interactions with iron, which are still not clear. Two main concepts have been
proposed - Adr autooxidation and redox interactions with iron, the most abundant
transition metal in human plasma 5
. Fe3+ is known to build complexes with catechols 6
, but
data on Fe3+ coordinate interactions with Adr at physiological pH are missing. In addition
to its (patho)physiological role, Adr is of interest from the aspect of development of
catecholamine-rich biopolymers with adhesive properties and metelloorganic frameworks
7,8. The adhesion and other properties materials are based on the cross-linking via
coordinate bonds with Fe3+ at pH > 7. Finally, ligands might dramatically alter the redox
potential of Fe3+/Fe2+ couple 9
. It has been shown that specific ligands with high affinity
for Fe3+, including some catechols, might promote the oxidation and increase the reactivity
of Fe2+ with molecular oxygen 10.
The aim of our study was to examine the nature of Adr interactions with Fe3+ and Fe2+:
stoichiometry, sites of coordinate bonds formation and structure of complex(es), and redox
activity, at pH 7.4 and different concentration ratios. The coordinate and redox interactions
were investigated using UV/Vis spectrophotometry, low temperature EPR, Raman
143
spectroscopy, cyclic voltammetry, and oximetry. The stability of Adr in the studied
reactions was monitored by HPLC.
At pH 7.4, Adr forms complexes with Fe3+, in the 1:1, and 3:1 stoichiometry, depending on
(high or low) Adr/Fe3+ concentration ratio. The high-spin Fe3+ 1:1 and 3:1 complexes show
different symmetries, with the 3:1 complex displaying higher EPR spectral anisotropy.
Raman spectroscopy showed that oxygen atoms on the catechol ring represent the sites of
coordinate bond formation in the bidentate Adr-Fe3+ complex. The bonds appear to be
stronger in the 1:1 complex, and not to share the same plane with the ring. On the other
hand, Adr and Fe2+ build a complex that acts as a strong reducing agent. In the presence of
O2, this leads to the production of H2O2, and to a facilitated formation of Adr/Fe3+
complexes. Adr is not oxidized in this process, i.e. iron is not an electron shuttle but
electron donor. Catalyzed oxidation of Fe2+ in the presence of Adr represents a plausible
chemical basis of stress-related damage of heart cells. In addition, our results imply that
the application/pre-binding of Fe2+ followed by oxidation at pH > 7 might be a simple
alternative strategy for promotion of cross-linking in catecholamine-rich biopolymers
frameworks.",
publisher = "Biohemijsko društvo Srbije",
journal = "Serbian Biochemical Society, Seventh Conference. "Biochemistry of Control in Life and Technology"",
title = "Ligand and redox - interactions of adrenaline with iron at physiological pH",
pages = "144-143",
url = "https://hdl.handle.net/21.15107/rcub_rimsi_2838"
}

Korać Jačić, J., Stanković, D., Stanić, M., Bajuk-Bogdanovic, D., Žižić, M., Bogdanović Pristov, J., Popovic Bijelic, A.,& Spasojević, I.. (2017). Ligand and redox - interactions of adrenaline with iron at physiological pH. in Serbian Biochemical Society, Seventh Conference. "Biochemistry of Control in Life and Technology"
Biohemijsko društvo Srbije., 143-144.
https://hdl.handle.net/21.15107/rcub_rimsi_2838

Korać Jačić J, Stanković D, Stanić M, Bajuk-Bogdanovic D, Žižić M, Bogdanović Pristov J, Popovic Bijelic A, Spasojević I. Ligand and redox - interactions of adrenaline with iron at physiological pH. in Serbian Biochemical Society, Seventh Conference. "Biochemistry of Control in Life and Technology". 2017;:143-144.
https://hdl.handle.net/21.15107/rcub_rimsi_2838 .

Korać Jačić, Jelena, Stanković, Dalibor, Stanić, Marina, Bajuk-Bogdanovic, Danica, Žižić, Milan, Bogdanović Pristov, Jelena, Popovic Bijelic, Ana, Spasojević, Ivan, "Ligand and redox - interactions of adrenaline with iron at physiological pH" in Serbian Biochemical Society, Seventh Conference. "Biochemistry of Control in Life and Technology" (2017):143-144,
https://hdl.handle.net/21.15107/rcub_rimsi_2838 .

TY  - JOUR
AU  - Bozic, Bojana
AU  - Korać Jačić, Jelena
AU  - Stanković, Dalibor M.
AU  - Stanić, Marina
AU  - Popovic-Bijelic, Ana
AU  - Bogdanović Pristov, Jelena
AU  - Spasojević, Ivan
AU  - Bajčetić, Milica
PY  - 2017
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1044
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.
PB  - Elsevier Ireland Ltd, Clare
T2  - Chemico-Biological Interactions
T1  - Mechanisms of redox interactions of bilirubin with copper and the effects of penicillamine
EP  - 134
SP  - 129
VL  - 278
DO  - 10.1016/j.cbi.2017.10.022
ER  - 

@article{
author = "Bozic, Bojana and Korać Jačić, Jelena and Stanković, Dalibor M. and Stanić, Marina and Popovic-Bijelic, Ana 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.",
publisher = "Elsevier Ireland Ltd, Clare",
journal = "Chemico-Biological Interactions",
title = "Mechanisms of redox interactions of bilirubin with copper and the effects of penicillamine",
pages = "134-129",
volume = "278",
doi = "10.1016/j.cbi.2017.10.022"
}

Bozic, B., Korać Jačić, J., Stanković, D. M., Stanić, M., Popovic-Bijelic, A., 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
Elsevier Ireland Ltd, Clare., 278, 129-134.
https://doi.org/10.1016/j.cbi.2017.10.022

Bozic B, Korać Jačić J, Stanković DM, Stanić M, Popovic-Bijelic A, 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 .

Bozic, Bojana, Korać Jačić, Jelena, Stanković, Dalibor M., Stanić, Marina, Popovic-Bijelic, Ana, 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 . .

TY  - JOUR
AU  - Stević, Nenad
AU  - Korać Jačić, Jelena
AU  - Pavlović, Jelena
AU  - Nikolic, Miroslav
PY  - 2016
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1008
AB  - The supplementation of monosilicic acid [Si(OH)(4)] to the root growing medium is known to protect plants from toxic levels of iron (Fe), copper (Cu) and manganese (Mn), but also to mitigate deficiency of Fe and Mn. However, the physicochemical bases of these alleviating mechanisms are not fully understood. Here we applied low-T electron paramagnetic resonance (EPR) spectroscopy to examine the formation of complexes of Si(OH)(4) with Mn2+, Fe3+, and Cu2+ in water and in xylem sap of cucumber (Cucumis sativus L.) grown without or with supply of Si(OH)(4). EPR, which is also useful in establishing the redox state of these metals, was combined with measurements of total concentrations of metals in xylem sap by inductive coupled plasma. Our results show that Si(OH)(4) forms coordination bonds with all three metals. The strongest interactions of Si(OH)(4) appear to be with Cu2+ (1/1 stoichiometry) which might lead to Cu precipitation. In line with this in vitro findings, Si(OH)(4) supply to cucumber resulted in dramatically lower concentration of this metal in the xylem sap. Further, it was demonstrated that Si(OH)(4) supplementation causes pro-reductive changes that contribute to the maintenance of Fe and, in particular, Mn in the xylem sap in bioavailable 2+ form. Our results shed more light on the intertwined reactions between Si(OH)(4) and transition metals in plant fluids (e.g. xylem sap).
PB  - Springer, Dordrecht
T2  - Biometals
T1  - Binding of transition metals to monosilicic acid in aqueous and xylem (Cucumis sativus L.) solutions: a low-T electron paramagnetic resonance study
EP  - 951
IS  - 5
SP  - 945
VL  - 29
DO  - 10.1007/s10534-016-9966-9
ER  - 

@article{
author = "Stević, Nenad and Korać Jačić, Jelena and Pavlović, Jelena and Nikolic, Miroslav",
year = "2016",
abstract = "The supplementation of monosilicic acid [Si(OH)(4)] to the root growing medium is known to protect plants from toxic levels of iron (Fe), copper (Cu) and manganese (Mn), but also to mitigate deficiency of Fe and Mn. However, the physicochemical bases of these alleviating mechanisms are not fully understood. Here we applied low-T electron paramagnetic resonance (EPR) spectroscopy to examine the formation of complexes of Si(OH)(4) with Mn2+, Fe3+, and Cu2+ in water and in xylem sap of cucumber (Cucumis sativus L.) grown without or with supply of Si(OH)(4). EPR, which is also useful in establishing the redox state of these metals, was combined with measurements of total concentrations of metals in xylem sap by inductive coupled plasma. Our results show that Si(OH)(4) forms coordination bonds with all three metals. The strongest interactions of Si(OH)(4) appear to be with Cu2+ (1/1 stoichiometry) which might lead to Cu precipitation. In line with this in vitro findings, Si(OH)(4) supply to cucumber resulted in dramatically lower concentration of this metal in the xylem sap. Further, it was demonstrated that Si(OH)(4) supplementation causes pro-reductive changes that contribute to the maintenance of Fe and, in particular, Mn in the xylem sap in bioavailable 2+ form. Our results shed more light on the intertwined reactions between Si(OH)(4) and transition metals in plant fluids (e.g. xylem sap).",
publisher = "Springer, Dordrecht",
journal = "Biometals",
title = "Binding of transition metals to monosilicic acid in aqueous and xylem (Cucumis sativus L.) solutions: a low-T electron paramagnetic resonance study",
pages = "951-945",
number = "5",
volume = "29",
doi = "10.1007/s10534-016-9966-9"
}

Stević, N., Korać Jačić, J., Pavlović, J.,& Nikolic, M.. (2016). Binding of transition metals to monosilicic acid in aqueous and xylem (Cucumis sativus L.) solutions: a low-T electron paramagnetic resonance study. in Biometals
Springer, Dordrecht., 29(5), 945-951.
https://doi.org/10.1007/s10534-016-9966-9

Stević N, Korać Jačić J, Pavlović J, Nikolic M. Binding of transition metals to monosilicic acid in aqueous and xylem (Cucumis sativus L.) solutions: a low-T electron paramagnetic resonance study. in Biometals. 2016;29(5):945-951.
doi:10.1007/s10534-016-9966-9 .

Stević, Nenad, Korać Jačić, Jelena, Pavlović, Jelena, Nikolic, Miroslav, "Binding of transition metals to monosilicic acid in aqueous and xylem (Cucumis sativus L.) solutions: a low-T electron paramagnetic resonance study" in Biometals, 29, no. 5 (2016):945-951,
https://doi.org/10.1007/s10534-016-9966-9 . .