Antioxidant defences in the first life phases of the sturgeon Acipenser naccarii

A study has been made of the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR), as well as of lipid peroxidation and of glutathione, during the first stages of ontogenic development of the sturgeon Acipenser naccarii: the embryo within the egg, the free embryo (with vitellin reserves), and the juvenile. Also, the same determinations were made in Artemia nauplii to determine the possible influence of the presence of live food in the quantification of the antioxidant-enzyme pool of the sturgeon. Activity was found for the antioxidant enzymes SOD, CAT, and GPX in all the stages of ontogenic development corresponding to the first month of life of the sturgeon A. naccarii. Notable activity of these enzymes was found during the embryonic phase. On the contrary, the GR activity was not detected in this phase, coinciding with a greater proportion of oxidized glutathione. In the sturgeon A. naccarii, after the embryo phase of free life, the activity of all the antioxidant enzymes tended to increase with age as did the glutathione levels. The results are compared with those previously determined in the different organs of the adult. The marked activity of the antioxidant enzymes found in the sturgeon A. naccarii during the first month of life provides the sturgeon effective protection against oxidative damage.