Metallothionein levels in Algerian mice (Mus spretus) exposed to elemental pollution: An ecophysiological approach

Centro de Biologia Ambiental, Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Edificio C2, 1749-016 Lisboa, Portugal. <>
Chemosphere (Impact Factor: 3.34). 05/2008; 71(7):1340-7. DOI: 10.1016/j.chemosphere.2007.11.024
Source: PubMed


The potential use of metallothioneins (MTs) as biomarkers of trace metal contamination was evaluated for the first time in the Algerian mouse (Mus spretus). Mice were collected seasonally in an abandoned mining area (Aljustrel) and in a reference area, both located in southern Portugal. MT levels were quantified in liver and kidney by differential pulse polarography and hepatic elemental concentrations (Mn, Fe, Cu, Zn, Se) were determined by particle-induced X-ray emission. Hepatic iron and selenium concentrations were elevated in mice from Aljustrel mine when compared to reference animals. MTs levels were averagely higher in mice from Aljustrel than those originated from the reference area. A season-dependent significant effect was found on the hepatic and renal MT concentrations, characterized by higher levels in winter and lower in autumn. In contaminated mice positive relationship between liver elemental contents (Cu in autumn and Fe in winter) and MTs were found. The seasonal variation of MT suggests that probably physiological and environmental factors could influence hepatic and renal MT induction. Results seem to imply that some environmental disturbance occur in the vicinity of the Aljustrel mine. Therefore, for the management purposes MT levels should be followed in liver of M. spretus, especially in winter. Furthermore, other physiological factors that could influence MT expression and turnover in Algerian mouse should also be monitored.

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Available from: Ana Maria Viegas-Crespo
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    • "The relationships between exposure to metals and MT levels have been well studied in the laboratory for certain mammal species, mainly rodents used as animal models (mouse and rat) and also for a wild small mammal, the bank vole Myodes (ex-Clethrionomys ) glareolus (Wlostowski, 1992b; Wlostowski and Krasowska, 1999; Klaassen et al., 2009). However, few field studies investigated the relationships between metal accumulation and MT levels in wild terrestrial vertebrates except in recent biomonitoring studies using MTs as exposure biomarkers (Rogival et al., 2007a; Marques et al., 2008; Vanparys et al., 2008). For small mammals, some studies showed that MT levels were more elevated in individuals coming from contaminated areas (Damek-Poprawa, 2002; Rogival et al., 2007a; Swiergosz-Kowalewska et al., 2007; Marques et al., 2008). "
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