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Differential antioxidant protection against oxidants by esculetin or quercetin in human leukemia NB4 cells
D. Rossin et al. / Free Radical Biology and Medicine 108 (2017) S18–S107
P-023
Differential antioxidant protection against oxidants by esculetin or quercetin in human leukemia NB4 cells Virginia Rubio, Ana I. García-Pérez, Angel Herráez, Carlos Ordóñez, Gema Herranz, M. Cristina Tejedor, José C. Diez Bioquímica y Biología Molecular. Universidad de Alcalá, Alcalá de Henares (Madrid) Spain Keywords: Esculetin; quercetin; leukemia; hydrogen peroxide; tert-butyl hydroperoxide
Esculetin (6,7-dihydrocoumarin) and the flavonoid quercetin (3,5,7,3',4' pentahydroxyflavone) show different pharmacological properties probably related to effects on redox homeostasis. Human leukemia NB4 cells were preincubated for 30 min or 2 h with either 100 μM esculetin or 25 μM quercetin. The cells were then treated with 1 mM H2O2 or 250 μM tert-butyl hydroperoxide (tBHP) for 1 h. Pretreatments with quercetin prevented loss of cell viability (impermeability to PI) induced by H2O2 or t-BHP. Treatment with 1 mM H2O2 for 1 h produced lower apoptotic cells (26%) than 250 μM t-BHP (38%). Pretreatments with esculetin increased the apoptosis induced by H2O2 but reduced significantly the apoptosis produced by t-BHP. Quercetin reduced apoptosis produced by H2O2 and wholly protects against apoptosis induced by t-BHP. Superoxide was increased by treatment with H2O2 or t-BHP. Esculetin or quercetin increased the levels of superoxide in cells treated with H2O2 but reduced them in cells treated with t-BHP. Esculetin but not quercetin almost prevented peroxide production by H2O2. Our results show different effects of antioxidant treatment on leukemia cells and possible differential applications for antitumor therapy with either of those antioxidant compounds used.
S25
NFkB p50 in the nucleus. This could suggest formation of inhibitory p50 homodimers possibly related with anti-inflammatory response. Lipoxygenase expression was reduced either by esculetin or quercetin. A significant increase of Nrf2 in the nucleus of NB4 cells treated with 100 μM esculetin for 19 hours was observed. Quercetin increased the levels of Nrf2 in the cytosol reducing them in the nucleus. Superoxide dismutase (SOD) expression increased in NB4 cells treated with esculetin in contrast with quercetin. All these data support a relevant differential role for NFkB and Nrf2 in antiinflamatory and redox response when apoptosis was induced by esculetin or quercetin in human leukemia NB4 cells. E-mail address: [email protected] (J.C. Diez) http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.109
P-025
Oxidative damage, antioxidant defense and DNA repair capacity in patients with Primary Dyslipidemia Nayade Pereira-Roche, Gretel Riverón-Forment, Reinaldo Gutiérrez-Gutiérrez, Alfredo Nasiff-Hadad, Judith Pupo-Balboa, Anamarys Pandolfi-Blanco National Center of Medical Genetics Cuba, Cuba
Bioquímica y Biología Molecular. Universidad de Alcalá, Alcalá de Henares (Madrid) Spain
Introduction: Primary Dyslipidemia is a group of genetic disorders of lipid metabolism. Biomolecules oxidative damage has been reported in those patients, although DNA repair capacity is less reported. The aim of this work is evaluate oxidative stress biomarkers and DNA repair capacity in dyslipidemic patients. Material and Methods: Plasma levels of malondialdehyde, advanced oxidation products of proteins and GSH, as well as the activities of SOD1, catalase, glutathione peroxidase and glutathione reductase were measured in patients from a Hospital in Havana. Comet assay was used to evaluate single strand breaks, oxidation-induced DNA damage, and repair capacity in isolated lymphocytes. Results: Levels of plasma MDA and GSH were higher in patients, as well as the enzymatic activity of GPx and GR. However, CAT and SOD1 activities did not significantly differ between patients and healthy controls. Additionally, no differences in DNA damage were observed between groups, but DNA repair capacity was significantly slower in patients, mainly in patients with Familiar Hypercholesterolemia (FH). Combined Hyperlipoproteinemia patients showed normal DNA repair. Conclusions: These findings show alterations in biomarkers of oxidative stress in patients. The deficiencies in the repair mechanisms could be related with the clinic evolution and the severity of complications in patients with FH.
Keywords: Esculetin; quercetin; leukemia; NFkB; Nrf2
E-mail address: [email protected] (N. Pereira-Roche)
E-mail address: [email protected] (J.C. Diez) http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.108
P-024
Nrf 2 and NFkB involvement in the antioxidant action of esculetin or quercetin in human leukemia NB4 cells Virginia Rubio, Ana I. García-Pérez, Angel Herráez, Carlos Ordóñez, Gema Herranz, M. Cristina Tejedor, José C. Diez
Esculetin (6,7-dihydrocoumarin) and the flavonoid quercetin (3,5,7,3',4' pentahydroxyflavone) are compounds that could change the balance of redox homeostasis. NB4 leukemia cells treated with 25 μM quercetin for 24 h and with esculetin at either 100 or 500 μM for different times. Quercetin increased the levels of pro-inflammatory NFkB p65 in the nucleus correspondingly reducing them in the cytosol. The levels of NFkB p65 decreased in the nucleus at high esculetin concentration treatments for long times (19 h), concomitantly, increasing the levels of anti-inflammatory
http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.110
P-023
Differential antioxidant protection against oxidants by esculetin or quercetin in human leukemia NB4 cells Virginia Rubio, Ana I. García-Pérez, Angel Herráez, Carlos Ordóñez, Gema Herranz, M. Cristina Tejedor, José C. Diez Bioquímica y Biología Molecular. Universidad de Alcalá, Alcalá de Henares (Madrid) Spain Keywords: Esculetin; quercetin; leukemia; hydrogen peroxide; tert-butyl hydroperoxide
Esculetin (6,7-dihydrocoumarin) and the flavonoid quercetin (3,5,7,3',4' pentahydroxyflavone) show different pharmacological properties probably related to effects on redox homeostasis. Human leukemia NB4 cells were preincubated for 30 min or 2 h with either 100 μM esculetin or 25 μM quercetin. The cells were then treated with 1 mM H2O2 or 250 μM tert-butyl hydroperoxide (tBHP) for 1 h. Pretreatments with quercetin prevented loss of cell viability (impermeability to PI) induced by H2O2 or t-BHP. Treatment with 1 mM H2O2 for 1 h produced lower apoptotic cells (26%) than 250 μM t-BHP (38%). Pretreatments with esculetin increased the apoptosis induced by H2O2 but reduced significantly the apoptosis produced by t-BHP. Quercetin reduced apoptosis produced by H2O2 and wholly protects against apoptosis induced by t-BHP. Superoxide was increased by treatment with H2O2 or t-BHP. Esculetin or quercetin increased the levels of superoxide in cells treated with H2O2 but reduced them in cells treated with t-BHP. Esculetin but not quercetin almost prevented peroxide production by H2O2. Our results show different effects of antioxidant treatment on leukemia cells and possible differential applications for antitumor therapy with either of those antioxidant compounds used.
S25
NFkB p50 in the nucleus. This could suggest formation of inhibitory p50 homodimers possibly related with anti-inflammatory response. Lipoxygenase expression was reduced either by esculetin or quercetin. A significant increase of Nrf2 in the nucleus of NB4 cells treated with 100 μM esculetin for 19 hours was observed. Quercetin increased the levels of Nrf2 in the cytosol reducing them in the nucleus. Superoxide dismutase (SOD) expression increased in NB4 cells treated with esculetin in contrast with quercetin. All these data support a relevant differential role for NFkB and Nrf2 in antiinflamatory and redox response when apoptosis was induced by esculetin or quercetin in human leukemia NB4 cells. E-mail address: [email protected] (J.C. Diez) http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.109
P-025
Oxidative damage, antioxidant defense and DNA repair capacity in patients with Primary Dyslipidemia Nayade Pereira-Roche, Gretel Riverón-Forment, Reinaldo Gutiérrez-Gutiérrez, Alfredo Nasiff-Hadad, Judith Pupo-Balboa, Anamarys Pandolfi-Blanco National Center of Medical Genetics Cuba, Cuba
Bioquímica y Biología Molecular. Universidad de Alcalá, Alcalá de Henares (Madrid) Spain
Introduction: Primary Dyslipidemia is a group of genetic disorders of lipid metabolism. Biomolecules oxidative damage has been reported in those patients, although DNA repair capacity is less reported. The aim of this work is evaluate oxidative stress biomarkers and DNA repair capacity in dyslipidemic patients. Material and Methods: Plasma levels of malondialdehyde, advanced oxidation products of proteins and GSH, as well as the activities of SOD1, catalase, glutathione peroxidase and glutathione reductase were measured in patients from a Hospital in Havana. Comet assay was used to evaluate single strand breaks, oxidation-induced DNA damage, and repair capacity in isolated lymphocytes. Results: Levels of plasma MDA and GSH were higher in patients, as well as the enzymatic activity of GPx and GR. However, CAT and SOD1 activities did not significantly differ between patients and healthy controls. Additionally, no differences in DNA damage were observed between groups, but DNA repair capacity was significantly slower in patients, mainly in patients with Familiar Hypercholesterolemia (FH). Combined Hyperlipoproteinemia patients showed normal DNA repair. Conclusions: These findings show alterations in biomarkers of oxidative stress in patients. The deficiencies in the repair mechanisms could be related with the clinic evolution and the severity of complications in patients with FH.
Keywords: Esculetin; quercetin; leukemia; NFkB; Nrf2
E-mail address: [email protected] (N. Pereira-Roche)
E-mail address: [email protected] (J.C. Diez) http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.108
P-024
Nrf 2 and NFkB involvement in the antioxidant action of esculetin or quercetin in human leukemia NB4 cells Virginia Rubio, Ana I. García-Pérez, Angel Herráez, Carlos Ordóñez, Gema Herranz, M. Cristina Tejedor, José C. Diez
Esculetin (6,7-dihydrocoumarin) and the flavonoid quercetin (3,5,7,3',4' pentahydroxyflavone) are compounds that could change the balance of redox homeostasis. NB4 leukemia cells treated with 25 μM quercetin for 24 h and with esculetin at either 100 or 500 μM for different times. Quercetin increased the levels of pro-inflammatory NFkB p65 in the nucleus correspondingly reducing them in the cytosol. The levels of NFkB p65 decreased in the nucleus at high esculetin concentration treatments for long times (19 h), concomitantly, increasing the levels of anti-inflammatory
http://dx.doi.org/10.1016/j.freeradbiomed.2017.04.110