title: ROS Production and Scavenging under Anoxia and Re-Oxygenation inArabidopsisCells: A Balance between Redox Signaling and Impairment.
abstract: Plants can frequently experience low oxygen concentrations due to environmental factors such as flooding or waterlogging. It has been reported that both anoxia and the transition from anoxia to re-oxygenation determine a strong imbalance in the cellular redox state involving the production of reactive oxygen species (ROS) and nitric oxide (NO). Plant cell cultures can be a suitable system to study the response to oxygen deprivation stress since a close control of physicochemical parameters is available when using bioreactors. For this purpose,Arabidopsiscell suspension cultures grown in a stirred bioreactor were subjected to a severe anoxic stress and analyzed during anoxia and re-oxygenation for alteration in ROS and NO as well as in antioxidant enzymes and metabolites. The results obtained by confocal microscopy showed the dramatic increase of ROS, H2O2, and NO during the anoxic shock. All the ascorbate-glutathione related parameters were altered during anoxia but restored during re-oxygenation. Anoxia also induced a slight but significant increase of α-tocopherol levels measured at the end of the treatment. Overall, the evaluation of cell defenses during anoxia and re-oxygenation inArabidopsiscell cultures revealed that the immediate response involving the overproduction of reactive species activated the antioxidant machinery including ascorbate-glutathione system, α-tocopherol and the ROS-scavenging enzymes ascorbate peroxidase, catalase, and peroxidase making cells able to counteract the stress toward cell survival.
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Bari Aldo Moro Bari, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Paradiso
authors.affiliation: Consiglio Nazionale delle Ricerche, Istituto di Scienze delle Produzioni Alimentari Lecce, Italy.
authors.forename: Sofia
authors.initials: S
authors.lastname: Caretto
authors.affiliation: Consiglio Nazionale delle Ricerche, Istituto di Scienze delle Produzioni Alimentari Lecce, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Leone
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Bari Aldo Moro Bari, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Bove
authors.affiliation: Consiglio Nazionale delle Ricerche, Istituto di Scienze delle Produzioni Alimentari Lecce, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: Nisi
authors.affiliation: Food Science and Nutrition Unit, Department of Medicine, Università Campus Bio-Medico di Roma Roma, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: De Gara
keywords: anoxic stress; antioxidant defenses; bioreactor; hydrogen peroxide; nitric oxide; reactive oxygen species