TY  - CONF
AU  - Ristić, Biljana
AU  - Krunić, Matija
AU  - Bošnjak, Mihajlo
AU  - Mirčić, Aleksandar
AU  - Tovilović-Kovačević, Gordana
AU  - Zogović, Nevena
AU  - Paunović, Verica
AU  - Trajković, Vladimir
AU  - Harhaji-Trajković, Ljubica
PY  - 2019
UR  - https://nordicautophagy.org/
UR  - https://nordicautophagy.org/report-3rd-nordic-autophagy-society-conference-in-utrecht/
UR  - http://radar.ibiss.bg.ac.rs/handle/123456789/6718
AB  - We investigated the ability of nano-sized graphen layers graphen quantum dots (GQD) to protect human neuroblastoma SH-SY5Y cells from toxicity of NO donor sodium nitroprusside (SNP). GQD prevented SNP induced mitochondrial depolarization and caspase dependent apoptosis. GQD partly suppressed neurotoxicity of NO donor DEA-NONOate and reduced SNP induced NO release in cells and cell-free system, suggesting that neuroprotective effects of GQD were partly mediated by their NO-scavanging capacity. However, GQD significantly preserved SH-SY5Y cells from light exhausted SNP, which was unable to produce NO, implying the existence of protective mechanism independent of NO-scavenging. Unspecific antioxidant, as well as hydroxyl radical (.OH) scavengers DMSO, vitamin E and gluthatione mimicked neuroprotective activity of GQD, while GQD diminished concentration of reactive oxygen species (ROS), especially .OH, in cells and cell culture medium, suggesting important role of .OH scavenging in neuroprotective activity of GQD. However ability of GQD to protect SH-SY5Y cells from SNP was not exclusively mediated by their ability to scavenge NO and ROS from medium, since it persisted after washing of GQD preincubated cells. Interestingly, GQD were found to be present in autophagosome-like vacuoles. Both SNP and GQD, and especially their combination, increased intracellular acidity characteristic for presence of autophagosomes, concentration of proautophagic protein beclin-1, while deacreased level of specific substrate of autophagic proteolysis p62. Moreover, SNP and GQD, and above all their combination, increased concentration of autophagosome-associated protein LC3 II in the presence of inhibitor of autophagic proteolysis bafilomycin A1. Finally, autophagy inhibitors 3-methzladenine, wortmannin and NH4Cl prevented neuroprotective ability of GQD, implying that GQD stimulated prosurvival autophagy in SNP treated neurons. Therefore, by demonstrating ability of GQD to protect SH-SY5Y neurons from SNP induced apoptosis by scavenging NO/ROS and stimulation of cytoprotective autophagy, our results suggest that GQD could be valuable candidate for treatment of neurodegenerative disorders.
PB  - Nordic Autophagy Society
C3  - 3rd Nordic Autophagy Society (NAS) Conference; 2019 May 22-24; Utrecht, Netherlands
T1  - Neuroprotective activity of GQD against SNP-induced toxicity are mediated by ROS/RNS scavenging and protective autophagy induction
SP  - 40
EP  - 40
UR  - https://hdl.handle.net/21.15107/rcub_ibiss_6718
ER  - 

@conference{
author = "Ristić, Biljana and Krunić, Matija and Bošnjak, Mihajlo and Mirčić, Aleksandar and Tovilović-Kovačević, Gordana and Zogović, Nevena and Paunović, Verica and Trajković, Vladimir and Harhaji-Trajković, Ljubica",
year = "2019",
abstract = "We investigated the ability of nano-sized graphen layers graphen quantum dots (GQD) to protect human neuroblastoma SH-SY5Y cells from toxicity of NO donor sodium nitroprusside (SNP). GQD prevented SNP induced mitochondrial depolarization and caspase dependent apoptosis. GQD partly suppressed neurotoxicity of NO donor DEA-NONOate and reduced SNP induced NO release in cells and cell-free system, suggesting that neuroprotective effects of GQD were partly mediated by their NO-scavanging capacity. However, GQD significantly preserved SH-SY5Y cells from light exhausted SNP, which was unable to produce NO, implying the existence of protective mechanism independent of NO-scavenging. Unspecific antioxidant, as well as hydroxyl radical (.OH) scavengers DMSO, vitamin E and gluthatione mimicked neuroprotective activity of GQD, while GQD diminished concentration of reactive oxygen species (ROS), especially .OH, in cells and cell culture medium, suggesting important role of .OH scavenging in neuroprotective activity of GQD. However ability of GQD to protect SH-SY5Y cells from SNP was not exclusively mediated by their ability to scavenge NO and ROS from medium, since it persisted after washing of GQD preincubated cells. Interestingly, GQD were found to be present in autophagosome-like vacuoles. Both SNP and GQD, and especially their combination, increased intracellular acidity characteristic for presence of autophagosomes, concentration of proautophagic protein beclin-1, while deacreased level of specific substrate of autophagic proteolysis p62. Moreover, SNP and GQD, and above all their combination, increased concentration of autophagosome-associated protein LC3 II in the presence of inhibitor of autophagic proteolysis bafilomycin A1. Finally, autophagy inhibitors 3-methzladenine, wortmannin and NH4Cl prevented neuroprotective ability of GQD, implying that GQD stimulated prosurvival autophagy in SNP treated neurons. Therefore, by demonstrating ability of GQD to protect SH-SY5Y neurons from SNP induced apoptosis by scavenging NO/ROS and stimulation of cytoprotective autophagy, our results suggest that GQD could be valuable candidate for treatment of neurodegenerative disorders.",
publisher = "Nordic Autophagy Society",
journal = "3rd Nordic Autophagy Society (NAS) Conference; 2019 May 22-24; Utrecht, Netherlands",
title = "Neuroprotective activity of GQD against SNP-induced toxicity are mediated by ROS/RNS scavenging and protective autophagy induction",
pages = "40-40",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_6718"
}

Ristić, B., Krunić, M., Bošnjak, M., Mirčić, A., Tovilović-Kovačević, G., Zogović, N., Paunović, V., Trajković, V.,& Harhaji-Trajković, L.. (2019). Neuroprotective activity of GQD against SNP-induced toxicity are mediated by ROS/RNS scavenging and protective autophagy induction. in 3rd Nordic Autophagy Society (NAS) Conference; 2019 May 22-24; Utrecht, Netherlands
Nordic Autophagy Society., 40-40.
https://hdl.handle.net/21.15107/rcub_ibiss_6718

Ristić B, Krunić M, Bošnjak M, Mirčić A, Tovilović-Kovačević G, Zogović N, Paunović V, Trajković V, Harhaji-Trajković L. Neuroprotective activity of GQD against SNP-induced toxicity are mediated by ROS/RNS scavenging and protective autophagy induction. in 3rd Nordic Autophagy Society (NAS) Conference; 2019 May 22-24; Utrecht, Netherlands. 2019;:40-40.
https://hdl.handle.net/21.15107/rcub_ibiss_6718 .

Ristić, Biljana, Krunić, Matija, Bošnjak, Mihajlo, Mirčić, Aleksandar, Tovilović-Kovačević, Gordana, Zogović, Nevena, Paunović, Verica, Trajković, Vladimir, Harhaji-Trajković, Ljubica, "Neuroprotective activity of GQD against SNP-induced toxicity are mediated by ROS/RNS scavenging and protective autophagy induction" in 3rd Nordic Autophagy Society (NAS) Conference; 2019 May 22-24; Utrecht, Netherlands (2019):40-40,
https://hdl.handle.net/21.15107/rcub_ibiss_6718 .

TY  - CONF
AU  - Bošnjak, Mihajlo
AU  - Ristić, Biljana
AU  - Krunić, Matija
AU  - Mirčić, Aleksandar
AU  - Zogović, Nevena
AU  - Tovilović-Kovačević, Gordana
AU  - Paunović, Verica
AU  - Trajković, Vladimir
AU  - Harhaji-Trajković, Ljubica
PY  - 2019
UR  - http://radar.ibiss.bg.ac.rs/handle/123456789/6341
AB  - We here investigated protective potential of nanoparticles graphene quantum dots
(GQD) against neurotoxicity of sodium nitroprusside (SNP), NO-donor and
antihypertensive drug widely used in studies of nitrosative stress-induced
neurotoxicity. GQD prevented SNP-induced apoptosis, caspase activation and
mitochondrial depolarization in SH-SY5Y neuroblastoma cells. GQD decreased SNP
generated nitrite accumulation in supernatants, as well as NO/ONOO- concentrations
in cells and cell-free medium. However, ONOO- and NO scavengers only slightly
suppressed SNP neurotoxicity. Moreover, light exhausted SNP, incapable of producing
NO, was toxic to SH-SY5Y cells, while GQD strongly reduced its neurotoxicity,
suggesting that defensive effect of GQD far exceeded their NO scavenging activity.
FeSO4 increased death of SH-SY5Y cells, while iron chelators decreased toxicity of
iron-containing SNP. GQD neutralized SNP generated reactive oxygen species (ROS)
production, particularly O2•− and •OH in both cells and cell-free condition.
Neurotoxicity of SNP was suppressed in the presence of unspecific antioxidants,
scavengers of •OH and lipid hydroperoxyl radicals, while it was increased with •OH
generating superoxide dismutase (SOD). Intracellular localization of GQD was
confirmed by transmission electron microscopy (TEM), while extensive washing of
cells preincubated with GQD, only partly reduced their protective activity, suggesting
that GQD exerted neuroprotective effect both intra- and extracellularly. Taken together,
these results suggested that GQD protected neuroblastoma cells by neutralizing reactive
nitrogen species (RNS) and ROS, predominantly •OH formed in Fenton reaction
catalyzed by iron derived from SNP. Therefore, GQD might be promising choice for
treatment of ROS/RNS-mediated neurodegenerative diseases.
PB  - Belgrade: Institute for Biological Research "Siniša Stanković"– National Institute of Republic of Serbia, University of Belgrade
C3  - Immunology at the Confluence of Multidisciplinary Approaches: abstract book: 2019 Dec 6-8; Belgrade, Serbia
T1  - Graphene quantum dots protect SH-SY5Y cells from SNP induced apoptosis by scavenging reactive oxygen and nitrogen species
SP  - 37
EP  - 37
UR  - https://hdl.handle.net/21.15107/rcub_ibiss_6341
ER  - 

@conference{
author = "Bošnjak, Mihajlo and Ristić, Biljana and Krunić, Matija and Mirčić, Aleksandar and Zogović, Nevena and Tovilović-Kovačević, Gordana and Paunović, Verica and Trajković, Vladimir and Harhaji-Trajković, Ljubica",
year = "2019",
abstract = "We here investigated protective potential of nanoparticles graphene quantum dots
(GQD) against neurotoxicity of sodium nitroprusside (SNP), NO-donor and
antihypertensive drug widely used in studies of nitrosative stress-induced
neurotoxicity. GQD prevented SNP-induced apoptosis, caspase activation and
mitochondrial depolarization in SH-SY5Y neuroblastoma cells. GQD decreased SNP
generated nitrite accumulation in supernatants, as well as NO/ONOO- concentrations
in cells and cell-free medium. However, ONOO- and NO scavengers only slightly
suppressed SNP neurotoxicity. Moreover, light exhausted SNP, incapable of producing
NO, was toxic to SH-SY5Y cells, while GQD strongly reduced its neurotoxicity,
suggesting that defensive effect of GQD far exceeded their NO scavenging activity.
FeSO4 increased death of SH-SY5Y cells, while iron chelators decreased toxicity of
iron-containing SNP. GQD neutralized SNP generated reactive oxygen species (ROS)
production, particularly O2•− and •OH in both cells and cell-free condition.
Neurotoxicity of SNP was suppressed in the presence of unspecific antioxidants,
scavengers of •OH and lipid hydroperoxyl radicals, while it was increased with •OH
generating superoxide dismutase (SOD). Intracellular localization of GQD was
confirmed by transmission electron microscopy (TEM), while extensive washing of
cells preincubated with GQD, only partly reduced their protective activity, suggesting
that GQD exerted neuroprotective effect both intra- and extracellularly. Taken together,
these results suggested that GQD protected neuroblastoma cells by neutralizing reactive
nitrogen species (RNS) and ROS, predominantly •OH formed in Fenton reaction
catalyzed by iron derived from SNP. Therefore, GQD might be promising choice for
treatment of ROS/RNS-mediated neurodegenerative diseases.",
publisher = "Belgrade: Institute for Biological Research "Siniša Stanković"– National Institute of Republic of Serbia, University of Belgrade",
journal = "Immunology at the Confluence of Multidisciplinary Approaches: abstract book: 2019 Dec 6-8; Belgrade, Serbia",
title = "Graphene quantum dots protect SH-SY5Y cells from SNP induced apoptosis by scavenging reactive oxygen and nitrogen species",
pages = "37-37",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_6341"
}

Bošnjak, M., Ristić, B., Krunić, M., Mirčić, A., Zogović, N., Tovilović-Kovačević, G., Paunović, V., Trajković, V.,& Harhaji-Trajković, L.. (2019). Graphene quantum dots protect SH-SY5Y cells from SNP induced apoptosis by scavenging reactive oxygen and nitrogen species. in Immunology at the Confluence of Multidisciplinary Approaches: abstract book: 2019 Dec 6-8; Belgrade, Serbia
Belgrade: Institute for Biological Research "Siniša Stanković"– National Institute of Republic of Serbia, University of Belgrade., 37-37.
https://hdl.handle.net/21.15107/rcub_ibiss_6341

Bošnjak M, Ristić B, Krunić M, Mirčić A, Zogović N, Tovilović-Kovačević G, Paunović V, Trajković V, Harhaji-Trajković L. Graphene quantum dots protect SH-SY5Y cells from SNP induced apoptosis by scavenging reactive oxygen and nitrogen species. in Immunology at the Confluence of Multidisciplinary Approaches: abstract book: 2019 Dec 6-8; Belgrade, Serbia. 2019;:37-37.
https://hdl.handle.net/21.15107/rcub_ibiss_6341 .

Bošnjak, Mihajlo, Ristić, Biljana, Krunić, Matija, Mirčić, Aleksandar, Zogović, Nevena, Tovilović-Kovačević, Gordana, Paunović, Verica, Trajković, Vladimir, Harhaji-Trajković, Ljubica, "Graphene quantum dots protect SH-SY5Y cells from SNP induced apoptosis by scavenging reactive oxygen and nitrogen species" in Immunology at the Confluence of Multidisciplinary Approaches: abstract book: 2019 Dec 6-8; Belgrade, Serbia (2019):37-37,
https://hdl.handle.net/21.15107/rcub_ibiss_6341 .