Biotransformation of genotoxic agents in marine sponges. Mechanisms and modulation.

Marine sponges do not appear to suffer from neoplastic diseases, in spite of possible high exposures resulting from their nature as sessile bottom filter feeders which pump large volumes of sea water. The assessment of several parameters related to the biotransformation of mutagens/carcinogens showed that the metabolic machinery of sponge medulla cells is mainly oriented towards detoxification, with some differences depending on species (Geodia cydonium or Tethya aurantium). Glutathione (GSH) levels were unexpectedly high in these cells, especially in Geodia, in which the concentration of this tripeptide was more than twice that measured in liver preparations from untreated rats, at least when related to the protein content.