title: Stress-related phenomena and detoxification mechanisms induced by common pharmaceuticals in alfalfa (Medicago sativa L.) plants.
abstract: Pharmaceutically active compounds (PhACs) have been recently shown to exert phytotoxic effects. The present study explores the uptake, systemic translocation, and abiotic stress responses and detoxification mechanisms induced by the exposure of alfalfa plants grown in sand under greenhouse conditions to four common, individually applied PhACs (10μgL(-1)) (diclofenac, sulfamethoxazole, trimethoprim, 17a-ethinylestradiol) and their mixture. Stress physiology markers (lipid peroxidation, proline, H2O2 and NO content, antioxidant activity assays) and gene expression levels of key plant detoxification components (including glutathione S-transferases, GST7, GST17; superoxide dismutases, CuZnSOD, FeSOD; proton pump, H(+)-ATP, and cytochrome c oxidase, CytcOx), were evaluated. PhACs were detected in significantly higher concentrations in roots compared with leaves. Stress related effects, manifested via membrane lipid peroxidation and oxidative burst, were local (roots) rather than systemic (leaves), and exacerbated when the tested PhACs were applied in mixture. Systemic accumulation of H2O2 in leaves suggests its involvement in signal transduction and detoxification responses. Increased antioxidant enzymatic activities, as well as upregulated transcript levels of GST7, GST17, H(+)-ATPase and CytcOx, propose their role in the detoxification of the selected PhACs in plants. The current findings provide novel biochemical and molecular evidence highlighting the studied PhACs as an emerging abiotic stress factor, and point the need for further research on wastewater flows under natural agricultural environments.
authors.affiliation: Agricultural Research Institute, P.O. Box 22016, 1516 Nicosia, Cyprus.
authors.forename: Anastasis
authors.initials: A
authors.lastname: Christou
authors.affiliation: Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, 3603 Lemesos, Cyprus.
authors.forename: Chrystalla
authors.initials: C
authors.lastname: Antoniou
authors.affiliation: Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, 3603 Lemesos, Cyprus.
authors.forename: Charalampia
authors.initials: C
authors.lastname: Christodoulou
authors.affiliation: NIREAS-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
authors.forename: Evroula
authors.initials: E
authors.lastname: Hapeshi
authors.affiliation: NIREAS-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Stavrou
authors.affiliation: NIREAS-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
authors.forename: Costas
authors.initials: C
authors.lastname: Michael
authors.affiliation: Department of Civil and Environmental Engineering, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus; NIREAS-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
authors.forename: Despo
authors.initials: D
authors.lastname: Fatta-Kassinos
authors.affiliation: Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, 3603 Lemesos, Cyprus. Electronic address: vassilis.fotopoulos@cut.ac.cy.
authors.forename: Vasileios
authors.initials: V
authors.lastname: Fotopoulos
mesh_terms: D006861:Hydrogen Peroxide / Q000378:metabolism; D015227:Lipid Peroxidation; D000455:Medicago sativa / Q000187:drug effects / Q000502:physiology*; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D012989:Soil Pollutants / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D012989:Soil Pollutants; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase
keywords: Cytochrome c oxidase; Glutathione S-transferase; Medicago sativa L.; Oxidative stress; Pharmaceutically active compounds; Proton pump