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Fungal contribution to reactive oxygen species (ROS) production exploits the host oxidative burst on its own benefit
E. Chiaradia et al. / Free Radical Biology and Medicine 96 (2016) S32–S69
accumulation), but only in the case of PA this effect was linearly correlated with cytotoxicity data measures as cell viability. Slight but significant lipogenic activity was observed also for vitamin E treatments that was not associated with any significant toxicity. CYP4F2 expression decreased in the liver of mice fed with a high-fat diet (HFD) and even more in CCl4 injected mice, a model of severe free radical-dependent steatohepatitis. In the NASH of choline deficient diet (CDAA), liver CYP4F2 expression increased in the earliest phases (1 to 3 months) of the dietary protocol to return to baseline in the latest time points, i.e. 6 to 9 months. PPAR-g levels showed a consensual change with CYP4F2 expression in both the HepG2 and HFD models. The same results were obtained for other detoxification genes relevant to vitamin E metabolism and lipotoxicity such as ALDH1A1 and GSTP. Preliminary analytical data demonstrate that α-TOH transformation to LCM, and particularly a-13’-OH, can be used as a reliable biomarker of CYP4F2 activity in both the in vivo and in vitro fatty liver models investigated in this study. Conclusions: The results suggest that lipotoxicity and inflammatory cues associated with fatty liver influence CYP4F2 expression together with other lipid metabolism and detoxification genes such as PPAR-g, ALDH1A1 and GSTP. Up- or down-regulation of can be observed in different in vivo models of NAFLD, such as HFD vs CDAA, suggesting diverse lipotoxicity patterns and mechanistic association with gene regulation effects. LCM analysis can be used as a surrogate biomarker to assess such molecular changes and the response to dietary vitamin E in NAFLD. http://dx.doi.org/10.1016/j.freeradbiomed.2016.04.130 P-68
Atheroprotective potentials of various plants Ozcan Erel 1, Zübeyde Ünlü 2 1
Yildirim Beyazit University, Faculty of Medicine, Department of Biochemistry, Ankara, Turkey 2 Harran University, Faculty of Medicine, Department of Biochemistry, Sanliurfa, Turkey Aims: Lipid peroxidation has the major role in the pathogenesis of atherosclerosis. In this study protective powers of 109 plants against in vitro lipid peroxidation were determined.
Methods: Peroxidation of LDL- cholesterol was occurred by free cupper ions. Protective powers of aquase and methanolic extracts of 109 plants were measured by Rel Assay TOS kit, based on the formation of ferric –xylenol orange complex. Total antioxidant capacities of the plants were measured by Rel Assay TAS kit, which is based on the decolorization of ABTS* radical cation and FRAP assay. Total phenolic contents were measured by Folin Ciocalteu assay. Total protective power, which reflects lag phase inhibition and suppression of the dien bound formation was calculated using area under curve of the monitored peroxidation reaction. Results: Thymus sp, Rhus coriaria, Caryophyllus Thymbra spicata and green tea plants have the most potent protective power against in vitro lipid peroxidation. These plants inhibited/prolonged the lag phase of the peroxidation periods. The plants also suppressed the dien bound formation. There were more significant
S61
positive correlations among protective power, total antioxidant capacity and total phenol levels. Conclusions: The mentioned plants, which have more potent protective effect against in vitro lipid peroxidation, may show atheroprotective effect as in vivo. http://dx.doi.org/10.1016/j.freeradbiomed.2016.04.131
P-69
Fungal contribution to reactive oxygen species (ROS) production exploits the host oxidative burst on its own benefit Jaime López-Cruz 1, Óscar Crespo-Salvador 1, Emma Fernández-Crespo 2, Pilar García-Agustín 2, Carmen González-Bosch 1 1
Departamento de Bioquímica y Biología Molecular, Universitat de Valencia, Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Valencia, Spain 2 Grupo de Bioquímica y Biotecnología, Área de Fisiología Vegetal, Departamento de Ciencias Agrarias y del Medio Natural, Escola Superior de Tecnologia i Ciències Experimentals, Universitat Jaume I, Castellón, Spain
Plants activate responses against pathogens, including oxidative burst. These reactive oxygen species (ROS) play a protective role and act as signals in plants. Necrotrophic pathogens can produce ROS to contribute to the oxidative imbalance in plants that benefits the colonization process. In a previous work, we demonstrated that tomato plants challenged with Botrytis cinerea accumulated ROS and callose, along with the induction of genes involved in defense, signaling and oxidative metabolism. Our results highlighted the relevance of oxylipin 12-oxo-phytodienoic acid (OPDA) in the response to this pathogen. OPDA is part of jasmonates, acting as key plant signals under oxidative stress conditions. Recently it was demonstrated that OPDA suppressed oxidative stress-induced death of human neuroblastoma cells, via activation of the Nrf2 pathway. Aims: Here, we studied the infection phenotype of the Δbcsod1 strain in both tomato and Arabidopsis plants. This mutant lacks bcsod1, which encodes the superoxide dismutase Cu-Zn-SOD. This enzyme catalyzes the conversion of superoxide ion (O2-) into hydrogen peroxide (H2O2). Results: Δbcsod1 displayed reduced virulence compared to wildtype B05.10 in both species. Plants infected with Δbcsod1 accumulated less H2O2 and higher O2- than those infected with B05.10, which is associated with an increase in defensive polymer callose. Our results demonstrate the relevance of OPDA in the response to changes in the oxidative environment. Although it is difficult to discriminate between fungal and host contributions to ROS production, our results support that BCSOD1 would alter the O2-/H2O2 rate contributing to the H2O2 level, which damages the plant tissue and reduces the activation of plant defense, increasing the susceptibility to B. cinerea. http://dx.doi.org/10.1016/j.freeradbiomed.2016.04.132
accumulation), but only in the case of PA this effect was linearly correlated with cytotoxicity data measures as cell viability. Slight but significant lipogenic activity was observed also for vitamin E treatments that was not associated with any significant toxicity. CYP4F2 expression decreased in the liver of mice fed with a high-fat diet (HFD) and even more in CCl4 injected mice, a model of severe free radical-dependent steatohepatitis. In the NASH of choline deficient diet (CDAA), liver CYP4F2 expression increased in the earliest phases (1 to 3 months) of the dietary protocol to return to baseline in the latest time points, i.e. 6 to 9 months. PPAR-g levels showed a consensual change with CYP4F2 expression in both the HepG2 and HFD models. The same results were obtained for other detoxification genes relevant to vitamin E metabolism and lipotoxicity such as ALDH1A1 and GSTP. Preliminary analytical data demonstrate that α-TOH transformation to LCM, and particularly a-13’-OH, can be used as a reliable biomarker of CYP4F2 activity in both the in vivo and in vitro fatty liver models investigated in this study. Conclusions: The results suggest that lipotoxicity and inflammatory cues associated with fatty liver influence CYP4F2 expression together with other lipid metabolism and detoxification genes such as PPAR-g, ALDH1A1 and GSTP. Up- or down-regulation of can be observed in different in vivo models of NAFLD, such as HFD vs CDAA, suggesting diverse lipotoxicity patterns and mechanistic association with gene regulation effects. LCM analysis can be used as a surrogate biomarker to assess such molecular changes and the response to dietary vitamin E in NAFLD. http://dx.doi.org/10.1016/j.freeradbiomed.2016.04.130 P-68
Atheroprotective potentials of various plants Ozcan Erel 1, Zübeyde Ünlü 2 1
Yildirim Beyazit University, Faculty of Medicine, Department of Biochemistry, Ankara, Turkey 2 Harran University, Faculty of Medicine, Department of Biochemistry, Sanliurfa, Turkey Aims: Lipid peroxidation has the major role in the pathogenesis of atherosclerosis. In this study protective powers of 109 plants against in vitro lipid peroxidation were determined.
Methods: Peroxidation of LDL- cholesterol was occurred by free cupper ions. Protective powers of aquase and methanolic extracts of 109 plants were measured by Rel Assay TOS kit, based on the formation of ferric –xylenol orange complex. Total antioxidant capacities of the plants were measured by Rel Assay TAS kit, which is based on the decolorization of ABTS* radical cation and FRAP assay. Total phenolic contents were measured by Folin Ciocalteu assay. Total protective power, which reflects lag phase inhibition and suppression of the dien bound formation was calculated using area under curve of the monitored peroxidation reaction. Results: Thymus sp, Rhus coriaria, Caryophyllus Thymbra spicata and green tea plants have the most potent protective power against in vitro lipid peroxidation. These plants inhibited/prolonged the lag phase of the peroxidation periods. The plants also suppressed the dien bound formation. There were more significant
S61
positive correlations among protective power, total antioxidant capacity and total phenol levels. Conclusions: The mentioned plants, which have more potent protective effect against in vitro lipid peroxidation, may show atheroprotective effect as in vivo. http://dx.doi.org/10.1016/j.freeradbiomed.2016.04.131
P-69
Fungal contribution to reactive oxygen species (ROS) production exploits the host oxidative burst on its own benefit Jaime López-Cruz 1, Óscar Crespo-Salvador 1, Emma Fernández-Crespo 2, Pilar García-Agustín 2, Carmen González-Bosch 1 1
Departamento de Bioquímica y Biología Molecular, Universitat de Valencia, Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Valencia, Spain 2 Grupo de Bioquímica y Biotecnología, Área de Fisiología Vegetal, Departamento de Ciencias Agrarias y del Medio Natural, Escola Superior de Tecnologia i Ciències Experimentals, Universitat Jaume I, Castellón, Spain
Plants activate responses against pathogens, including oxidative burst. These reactive oxygen species (ROS) play a protective role and act as signals in plants. Necrotrophic pathogens can produce ROS to contribute to the oxidative imbalance in plants that benefits the colonization process. In a previous work, we demonstrated that tomato plants challenged with Botrytis cinerea accumulated ROS and callose, along with the induction of genes involved in defense, signaling and oxidative metabolism. Our results highlighted the relevance of oxylipin 12-oxo-phytodienoic acid (OPDA) in the response to this pathogen. OPDA is part of jasmonates, acting as key plant signals under oxidative stress conditions. Recently it was demonstrated that OPDA suppressed oxidative stress-induced death of human neuroblastoma cells, via activation of the Nrf2 pathway. Aims: Here, we studied the infection phenotype of the Δbcsod1 strain in both tomato and Arabidopsis plants. This mutant lacks bcsod1, which encodes the superoxide dismutase Cu-Zn-SOD. This enzyme catalyzes the conversion of superoxide ion (O2-) into hydrogen peroxide (H2O2). Results: Δbcsod1 displayed reduced virulence compared to wildtype B05.10 in both species. Plants infected with Δbcsod1 accumulated less H2O2 and higher O2- than those infected with B05.10, which is associated with an increase in defensive polymer callose. Our results demonstrate the relevance of OPDA in the response to changes in the oxidative environment. Although it is difficult to discriminate between fungal and host contributions to ROS production, our results support that BCSOD1 would alter the O2-/H2O2 rate contributing to the H2O2 level, which damages the plant tissue and reduces the activation of plant defense, increasing the susceptibility to B. cinerea. http://dx.doi.org/10.1016/j.freeradbiomed.2016.04.132