title: Nitric oxide alleviates arsenic toxicity by reducing oxidative damage in the roots of Oryza sativa (rice).
abstract: Nitric oxide (NO) is a bioactive gaseous, multifunctional molecule playing a central role and mediating a variety of physiological processes and responses to biotic and abiotic stresses including heavy metals. The present study investigated whether NO applied exogenously as sodium nitroprusside (SNP) has any protective role against arsenic (As) toxicity in Oryza sativa (rice). Treatment with 50 microM SNP (a NO donor) significantly ameliorated the As-induced (25 or 50 microM) decrease in root and coleoptile length of rice. Further, As-induced oxidative stress measured in terms of malondialdehyde (MDA), superoxide ion (O(2)(-)), root oxidizability and H2O2 content was lesser upon supplementation of NO. It indicated a reactive oxygen species (ROS) scavenging activity of NO. NO addition reversed (only partially) the As-induced increase in activities of antioxidant enzymes - superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, and catalase. The study concludes that exogenous NO provides resistance to rice against As-toxicity and has an ameliorating effect against As-induced stress.
authors.affiliation: Department of Environment and Vocational Studies, Panjab University, Chandigarh, India. hpsingh_01@yahoo.com
authors.forename: Harminder P
authors.initials: HP
authors.lastname: Singh
authors.forename: Shalinder
authors.initials: S
authors.lastname: Kaur
authors.forename: Daizy R
authors.initials: DR
authors.lastname: Batish
authors.forename: Ved P
authors.initials: VP
authors.lastname: Sharma
authors.forename: Nidhi
authors.initials: N
authors.lastname: Sharma
authors.forename: Ravinder K
authors.initials: RK
authors.lastname: Kohli
mesh_terms: D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology*; D001151:Arsenic / Q000633:toxicity*; D019216:Metals, Heavy / Q000633:toxicity; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology*; D012275:Oryza / Q000378:metabolism*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D018517:Plant Roots / Q000187:drug effects* / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D019216:Metals, Heavy; D017382:Reactive Oxygen Species; D009569:Nitric Oxide; D001151:Arsenic