Correlation between the level of the potential biomarker, heat-shock protein, and the occurrence of DNA damage in the dab, Limanda limanda: a field study in the North Sea and the English Channel

In the present study, heat-shock protein of M-r 70 kDa (HSP70), a marker of cellular stress response, was validated as a potential biomarker under fie ld conditions. The dab, Limanda limanda (female, size greater than or equal to 25 cm, spawning maturity stage 2) was used as the indicator organism. T he data on HSP level were correlated with the occurrence of DNA damage, mea sured in the same specimens of L. limanda, to prove the usefulness of the m ethod. The area under investigation was the North Sea. Four locations were selected: station N01, close to Heligoland, in the North Sea; station N04 a t the Dogger Bank; station N06 at the Firth of Forth; and station G08 in th e English Channel. Ten animals from each location were selected and their l ivers used for the experiments. The results show that the highest levels of HSP70 (consisting of two forms of M-r 75 and 73 kDa) were in fish from sta tion N04, while low values were measured in livers from L. limanda collecte d at station N01. Intermediate levels were seen in the animals the two othe r locations. By application of a novel technique, it was found that the ext ent of DNA damage (single-strand breaks and alkaline labile sites) in fish liver parallels the levels of both HSP70 forms. Our results suggest that L. limanda may be a useful bioindicator and heat-shock proteins, a useful bio marker for monitoring of environmental pollution. (C) 2000 Elsevier Science Ltd. All rights reserved.