Iron and Oxidative Damage in Antarctic Molluscs.

GONZALEZ P.M. Y PUNTARULO S.

Buenos Aires

Conferencia; Scientific Committee on Antarctic Research (SCAR) XXXI & Open Science Conference; 2010

SETAC

Gills are contact tissues with the surrounding environment. King George Island is characterized by a high Fe level in its volcanic coast. Since natural exposure to this Fe concentrations may affect oxidative metabolism, gills from two molluscs species, Laternula elliptica and Nacella concinna (both intertidal and subtidal populations), were analyzed. In L. elliptica, total Fe content and labile Fe pool (LIP) were 3.81 ± 0.40 nmol Fe/mg FW, and 437 ± 60 pmol LIP/mg FW, respectively. Both N. concinna populations showed lower values for each parameter. However, the thiobarbituric reactive substances content was 383 ± 33, 321 ± 70 and 371 ± 31 pmol/mg FW for L. elliptica, N. concinna subtidal and N. concinna intertidal, respectively. This lack of difference in the oxidative damage to lipids suggested that other factors could affect Fe-dependent oxidative metabolism. The nitrite and nitrate content showed significantly higher values in N. concinna (101 ± 10, 99 ± 15 pmol/mg FW for subtidal and intertidal populations, respectively), as compared to L. elliptica (40 ± 6 pmol/mg FW). These results showed the influence of Fe content in the environment on the tissue metabolism, and suggested that nitrogen derivatives could be implicated in limiting Fe damage to lipids. Thus, information on nitrosative metabolism is crucial in these aquatic communities.