title: Oxidative stress decreases with elevation in the lizard Psammodromus algirus.
abstract: Oxidative stress is considered one of the main ecological and evolutionary forces. Several environmental stressors vary geographically and thus organisms inhabiting different sites face different oxidant environments. Nevertheless, there is scarce information about how oxidative damage and antioxidant defences vary geographically in animals. Here we study how oxidative stress varies from lowlands (300-700 m asl) to highlands (2200-2500 m asl) in the lizard Psammodromus algirus. To accomplish this, antioxidant enzymatic activity (catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione transferase, DT-diaphorase) and lipid peroxidation were assayed in tissue samples from the lizards' tail. Lipid peroxidation was higher in individuals from lowlands than from highlands, indicating higher oxidative stress in lowland lizards. These results suggest that environmental conditions are less oxidant at high elevations with respect to low ones. Therefore, our study shows that oxidative stress varies geographically, which should have important consequences for our understanding of geographic variation in physiology and life-history of organisms.
authors.affiliation: Department of Zoology, University of Granada, Avda Fuentenueva s/n, E-18071 Granada, Spain. Electronic address: sreguera@ugr.es.
authors.forename: Senda
authors.initials: S
authors.lastname: Reguera
authors.affiliation: Department of Zoology, University of Granada, Avda Fuentenueva s/n, E-18071 Granada, Spain. Electronic address: zamcam@ugr.es.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Zamora-Camacho
authors.affiliation: Department of Zoology, University of Granada, Avda Fuentenueva s/n, E-18071 Granada, Spain; Department of Cell Biology, University of Granada, Avda Fuentenueva s/n, E-18071 Granada, Spain. Electronic address: ctrenzad@ugr.es.
authors.forename: Cristina E
authors.initials: CE
authors.lastname: Trenzado
authors.affiliation: Department of Zoology, University of Granada, Avda Fuentenueva s/n, E-18071 Granada, Spain. Electronic address: anasanz@ugr.es.
authors.forename: Ana
authors.initials: A
authors.lastname: Sanz
authors.affiliation: Department of Zoology, University of Granada, Avda Fuentenueva s/n, E-18071 Granada, Spain. Electronic address: gmr@ugr.es.
authors.forename: Gregorio
authors.initials: G
authors.lastname: Moreno-Rueda
mesh_terms: D000531:Altitude; D000818:Animals; D002374:Catalase / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D015227:Lipid Peroxidation; D008116:Lizards / Q000378:metabolism / Q000502:physiology*; D018384:Oxidative Stress / Q000235:genetics*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005982:Glutathione Transferase
keywords: Antioxidant enzymes; Antioxidant protection; Elevation gradient; Lipid peroxidation; Lizards; Ultraviolet radiation