title: Manganese-induced oxidative stress in two ontogenetic stages of chamomile and amelioration by nitric oxide.
abstract: Impact of manganese (Mn(2+)) excess (100, 500 and 1000 μM over 7 days) on two ontogenetic stages (7-week-old plants and 7-day-old seedlings) of Matricaria chamomilla was compared. Mn excess depressed growth of seedlings (but not germination) and stimulated oxidative stress (ROS and lipid peroxidation) in both plants and seedlings. Growth inhibition could be evoked by higher Mn uptake and higher translocation factor in seedlings than in plants. Total thiols staining revealed elevation in almost all treatments. In 7-week-old plants, activity of peroxidases increased slightly and rather decreased under high Mn doses. Superoxide rather than hydrogen peroxide contributed to visualized ROS presence. Fluorescence of nitric oxide (NO) showed stimulation in plants but decrease in seedlings. Impact of exogenous nitric oxide donor (sodium nitroprusside/SNP) was therefore tested and results showed amelioration of 1000 μM Mn-induced oxidative stress in seedlings (decrease in H2O2 and increase in NO content while antioxidative enzyme activities were variably affected) concomitantly with depleted Mn accumulation. It is concluded that NO participates in tolerance to Mn excess but negative effects of the highest SNP dose were also observed. Extensive fluorescence microscopy is also explanatively discussed.
authors.affiliation: Institute of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic. Electronic address: jozkovacik@yahoo.com.
authors.forename: Jozef
authors.initials: J
authors.lastname: Kováčik
authors.affiliation: Department of Natural Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42 Brno, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Babula
authors.affiliation: Institute of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic.
authors.forename: Josef
authors.initials: J
authors.lastname: Hedbavny
authors.affiliation: Institute of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Švec
mesh_terms: D000222:Adaptation, Physiological; D000975:Antioxidants / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D008345:Manganese / Q000009:adverse effects* / Q000378:metabolism; D031168:Matricaria / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D008856:Microscopy, Fluorescence / Q000379:methods; D009569:Nitric Oxide / Q000378:metabolism* / Q000494:pharmacology; D020030:Nitric Oxide Donors / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D018384:Oxidative Stress; D010544:Peroxidases / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism
chemical_list: D000975:Antioxidants; D020030:Nitric Oxide Donors; D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds; D013481:Superoxides; D009599:Nitroprusside; D009569:Nitric Oxide; D008345:Manganese; D006861:Hydrogen Peroxide; D010544:Peroxidases
keywords: Fluorescence microscopy; Heavy metals; Mineral nutrients; Ontogenesis; Reactive oxygen species