title: Integrated assessment of biochemical markers in premetamorphic tadpoles of three amphibian species exposed to glyphosate- and methidathion-based pesticides in single and combination forms.
abstract: In this study, we evaluated the toxic effects of a glyphosate-based herbicide (GBH) and a methidathion-based insecticide (MBI), individually and in combination, on premetamorphic tadpoles of three anuran species: Pelophylax ridibundus, Xenopus laevis, and Bufotes viridis. Based on the determined 96-h LC50 values of each species, the effects of a series of sublethal concentrations of single pesticides and their mixtures after 96-h exposure and also the time-related effects of a high sublethal concentration of each pesticide were evaluated, with determination of changes in selected biomarkers: glutathione S-transferase (GST), glutathione reductase (GR), acetylcholinesterase (AChE), carboxylesterase (CaE), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH). Also, the integrated biomarker response (IBR) was used to assess biomarker responses and quantitatively evaluate toxicological effects. Isozyme differences in CaE inhibition were assessed using native page electrophoresis; results showed that GBH to cause structural changes in the enzyme but not CaE inhibition in P. ridibundus. In general, single MBI and pesticide mixture exposures increased GST activity, while single GBH exposures decreased GST activity in exposed tadpoles. The AChE and CaE activities were inhibited after exposure to all single MBI and pesticide mixtures. Also, higher IBR values and GST, GR, AST, and LDH activities were determined for pesticide mixtures compared with single-pesticide exposure. This situation may be indicative of a synergistic interaction between pesticides and a sign of a more stressful condition.
authors.affiliation: Laboratory of Environmental Toxicology, Department of Biology, Faculty of Arts and Science, Inonu University, 44280, Malatya, Turkey. Electronic address: abbas.gungordu@inonu.edu.tr.
authors.forename: Abbas
authors.initials: A
authors.lastname: Güngördü
authors.affiliation: Department of Food Engineering, Faculty of Engineering, Adiyaman University, 02040, Adiyaman, Turkey.
authors.forename: Miraç
authors.initials: M
authors.lastname: Uçkun
authors.affiliation: Department of Science Education, Faculty of Education, Adiyaman University, 02040, Adiyaman, Turkey.
authors.forename: Ertan
authors.initials: E
authors.lastname: Yoloğlu
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D001219:Aspartate Aminotransferases / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D002025:Bufonidae; D043182:Carboxylesterase / Q000037:antagonists & inhibitors / Q000378:metabolism; D002800:Cholinesterase Inhibitors / Q000633:toxicity*; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D005998:Glycine / Q000031:analogs & derivatives* / Q000633:toxicity; D006540:Herbicides / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D007814:Larva / Q000187:drug effects / Q000201:enzymology; D009946:Organothiophosphorus Compounds / Q000633:toxicity*; D011898:Ranidae; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D014982:Xenopus laevis; D000097797:Glyphosate
chemical_list: D000110:Acetylcholinesterase; D001219:Aspartate Aminotransferases; D015415:Biomarkers; D043182:Carboxylesterase; D002800:Cholinesterase Inhibitors; D005980:Glutathione Reductase; D005982:Glutathione Transferase; D005998:Glycine; D006540:Herbicides; D007306:Insecticides; D007770:L-Lactate Dehydrogenase; D009946:Organothiophosphorus Compounds; D014874:Water Pollutants, Chemical; D000097797:Glyphosate; C005828:methidathion
keywords: Amphibia; Biochemical markers; Glyphosate; Methidathion; Pesticide mixture