title: Elucidation of lead-induced oxidative stress in Talinum triangulare roots by analysis of antioxidant responses and DNA damage at cellular level.
abstract: Hydroponic experiments were performed with Talinum triangulare (Jacq.) Willd. focusing the root cellular biochemistry with special emphasis on DNA damage, structural, and elemental analyses in Pb(NO3)2 exposed with 0, 0.25, 0.5, 0.75, 1.0, and 1.25 mM for 7 days. Lead (Pb) increased reactive oxygen species production, lipid peroxidation, protein oxidation, cell death, and DNA damage and decreased the protein content in a dose-dependent manner. Likewise, a dose-dependent induction of antioxidative enzymes superoxide dismutase and catalase by Pb was evident. Ascorbate peroxidase on the other hand responded biphasically to Pb treatments by showing induction at low (0.25 and 0.50) and repression at high (0.75-1.25 mM) concentrations. The estimation of proline content also indicated a similar biphasic trend. Scanning electron microscope and energy-dispersive X-ray spectroscopy analysis showed that 1.25 mM Pb treatment resulted in ultrastructural modifications in roots and stem tissue that was marked by the change in the elemental profile. The findings pointed to the role of oxidative stress in the underlying Pb phytotoxicity and genotoxicity in T. triangulare.
authors.affiliation: Department of Plant Sciences, University of Hyderabad, Hyderabad 500046, India.
authors.forename: Abhay
authors.initials: A
authors.lastname: Kumar
authors.forename: M N V
authors.initials: MN
authors.lastname: Prasad
authors.forename: V
authors.initials: V
authors.lastname: Mohan Murali Achary
authors.forename: Brahma B
authors.initials: BB
authors.lastname: Panda
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D060387:Ascorbate Peroxidases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D020552:Comet Assay; D004249:DNA Damage; D029624:Ferns / Q000166:cytology / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000378:metabolism; D018527:Hydroponics / Q000379:methods; D007854:Lead / Q000633:toxicity*; D015227:Lipid Peroxidation / Q000187:drug effects; D008084:Lipoxygenase / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects*; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects*; D018547:Plant Stems / Q000166:cytology / Q000187:drug effects; D011392:Proline / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D007854:Lead; D011392:Proline; D006861:Hydrogen Peroxide; D060387:Ascorbate Peroxidases; D002374:Catalase; D008084:Lipoxygenase; D013482:Superoxide Dismutase