Annelie Gutsch1,2, Sophie Hendrix2,3, Gea Guerriero1, Jenny Renaut1, Stanley Lutts4, Saleh Alseekh5,6, Alisdair R Fernie5,6, Jean-Francois Hausman1, Jaco Vangronsveld2, Ann Cuypers2, Kjell Sergeant1. 1. GreenTech Innovation Center, Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, 5, Avenue des Hauts-Fourneaux, 4362 Esch-sur-Alzette, Luxembourg. 2. Centre for Environmental Sciences, Campus Diepenbeek, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium. 3. Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Friedrich-Ebert-Allee 144, 53113 Bonn, Germany. 4. Groupe de Recherche en Physiologie Végétale, Earth and Life Institute-Agronomy, Université Catholique de Louvain, 5, Place Croix du Sud, 1348 Louvain-la-Neuve, Belgium. 5. Max-Planck-Institute of Plant Molecular Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany. 6. Centre of Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria.
Abstract
As a common pollutant, cadmium (Cd) is one of the most toxic heavy metals accumulating in agricultural soils through anthropogenic activities. The uptake of Cd by plants is the main entry route into the human food chain, whilst in plants it elicits oxidative stress by unbalancing the cellular redox status. Medicago sativa was subjected to chronic Cd stress for five months. Targeted and untargeted metabolic analyses were performed. Long-term Cd exposure altered the amino acid composition with levels of asparagine, histidine and proline decreasing in stems but increasing in leaves. This suggests tissue-specific metabolic stress responses, which are often not considered in environmental studies focused on leaves. In stem tissue, profiles of secondary metabolites were clearly separated between control and Cd-exposed plants. Fifty-one secondary metabolites were identified that changed significantly upon Cd exposure, of which the majority are (iso)flavonoid conjugates. Cadmium exposure stimulated the phenylpropanoid pathway that led to the accumulation of secondary metabolites in stems rather than cell wall lignification. Those metabolites are antioxidants mitigating oxidative stress and preventing cellular damage. By an adequate adjustment of its metabolic composition, M. sativa reaches a new steady state, which enables the plant to acclimate under chronic Cd stress.
As a common pollutant, n class="Chemical">cadmium (Cd) is one of the most toxic heavy metals accumulating in agricultural soils through anthropogenic activities. The uptake of Cd by plants is the main entry route into the human food chain, whilst in plants it elicits oxidative stress by unbalancing the cellular redox status. Medicago sativa was subjected to chronic Cd stress for five months. Targeted and untargeted metabolic analyses were performed. Long-term Cd exposure altered the amino acid composition with levels of asparagine, histidine and proline decreasing in stems but increasing in leaves. This suggests tissue-specific metabolic stress responses, which are often not considered in environmental studies focused on leaves. In stem tissue, profiles of secondary metabolites were clearly separated between control and Cd-exposed plants. Fifty-one secondary metabolites were identified that changed significantly upon Cd exposure, of which the majority are (iso)flavonoid conjugates. Cadmium exposure stimulated the phenylpropanoid pathway that led to the accumulation of secondary metabolites in stems rather than cell wall lignification. Those metabolites are antioxidants mitigating oxidative stress and preventing cellular damage. By an adequate adjustment of its metabolic composition, M. sativa reaches a new steady state, which enables the plant to acclimate under chronic Cd stress.
Authors: Stephen A Bustin; Vladimir Benes; Jeremy A Garson; Jan Hellemans; Jim Huggett; Mikael Kubista; Reinhold Mueller; Tania Nolan; Michael W Pfaffl; Gregory L Shipley; Jo Vandesompele; Carl T Wittwer Journal: Clin Chem Date: 2009-02-26 Impact factor: 8.327
Authors: Ann Cuypers; Karen Smeets; Jos Ruytinx; Kelly Opdenakker; Els Keunen; Tony Remans; Nele Horemans; Nathalie Vanhoudt; Suzy Van Sanden; Frank Van Belleghem; Yves Guisez; Jan Colpaert; Jaco Vangronsveld Journal: J Plant Physiol Date: 2010-09-15 Impact factor: 3.549