title: 20-Hydroxyecdysone protects wheat seedlings (Triticum aestivum L.) against lead stress.
abstract: 20-Hydroxyecdysone (20E) is the most abundant phytoecdysteroid (PE) produced by plants, where it represents a protective molecule against insect attack. The aim of the present study was to assess the effects of 20E on the growth, metabolic enzymes and antioxidant systems of wheat seedlings under lead stress induced by Pb(NO3)2 (3 mM). Pre-treatment concentrations (0, 1, 3 and 5 μM) of 20E were applied for two days, then wheat seedlings were transferred for 5 days to a treatment solution containing lead nitrate. When plants were grown without pre-treatment, germination and growth were impaired, while signs of oxidative stress were observed. 20E pre-treatment (3 or 5 μM) was able to efficiently protect seedlings from Pb toxicity by reducing Pb uptake and Pb-induced oxidative stress, as well by enhancing Pb excretion. Thus, 20E pre-treatment maintains normal germination, elongation, biomass, and metabolism in spite of the presence of Pb. Our results show that 20E protects oxidative balance and enhances the anti-oxidative systems, and more specifically the ascorbate-glutathione system. To our knowledge, this study shows for the first time that 20E treatment induces metabolic changes that allow the plants to resist heavy metal stress.
authors.affiliation: PER-Centre des Etudes Environnementales Méditerranéennes, équipe de recherche Biotechnologies et Génie des Biomolécules, Faculté des Sciences et Techniques, Université Abdelmalek Essaadi, BP 416, Tangier, Morocco. Electronic address: mohamadi03@yahoo.fr.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Lamhamdi
authors.affiliation: Sorbonne Universités, UPMC, IBPS-BIOSIPE, Case 29, 7 Quai Saint Bernard, 75005, Paris, France.
authors.forename: René
authors.initials: R
authors.lastname: Lafont
authors.affiliation: Université Abdelmalek Essaâdi, Faculté Polydisciplinaire de Larache, BP 745, Larache, Morocco.
authors.forename: Kacem
authors.initials: K
authors.lastname: Rharrabe
authors.affiliation: PER-Centre des Etudes Environnementales Méditerranéennes, équipe de recherche Biotechnologies et Génie des Biomolécules, Faculté des Sciences et Techniques, Université Abdelmalek Essaadi, BP 416, Tangier, Morocco.
authors.forename: Fouad
authors.initials: F
authors.lastname: Sayah
authors.affiliation: PER-Centre des Etudes Environnementales Méditerranéennes, équipe de recherche Biotechnologies et Génie des Biomolécules, Faculté des Sciences et Techniques, Université Abdelmalek Essaadi, BP 416, Tangier, Morocco.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Aarab
authors.affiliation: Université Hassan I, Faculté Polydisciplinaire de Khouribga, BP 145, Khouribga, Morocco.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Bakrim
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D001205:Ascorbic Acid / Q000378:metabolism; D001673:Biodegradation, Environmental; D002374:Catalase / Q000378:metabolism; D004441:Ecdysterone / Q000494:pharmacology*; D018525:Germination / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D007854:Lead / Q000378:metabolism / Q000633:toxicity*; D008315:Malondialdehyde / Q000378:metabolism; D019216:Metals, Heavy / Q000378:metabolism / Q000633:toxicity; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress; D020011:Protective Agents / Q000494:pharmacology*; D036226:Seedlings / Q000187:drug effects* / Q000502:physiology; D012989:Soil Pollutants / Q000378:metabolism / Q000633:toxicity; D013312:Stress, Physiological; D013482:Superoxide Dismutase / Q000378:metabolism; D014908:Triticum / Q000187:drug effects* / Q000502:physiology
chemical_list: D000975:Antioxidants; D019216:Metals, Heavy; D020011:Protective Agents; D012989:Soil Pollutants; D007854:Lead; D008315:Malondialdehyde; D004441:Ecdysterone; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione; D001205:Ascorbic Acid
keywords: Abiotic stress; Antioxidant activity; Ascorbate-glutathione; Bioremediation; Pb phytotoxicity; Phytoecdysteroids; Wheat germination