<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><bold>Background.</bold> Microcystins (MCs) are cyclic heptapeptides that are considered to be liver specific toxins. They are potent tumour promoters and recent studies indicate that they are also genotoxic. In this study we measured DNA damage in lymphocytes, liver, kidney (cortex and medulla), lung, spleen and brain cells of male Fisher F344 rats that were exposed to sublethal dose (every second day 10 μg/kg b.w.; i.p) of micro-cystin-YR (MCYR) for one month.<bold>Methods.</bold> At the end of exposure the animals were sacrificed, the lymphocytes were isolated from blood taken from jugular vein, liver cells were obtained by perfusion with collagenase A and the cells from other organs were isolated by incubating small tissue pieces with collagenase A. The DNA damage in isolated cells was measured with the single cells gel electrophoresis (SCGE) also called the comet assay.<bold>Results.</bold> A significant increase of the % tail DNA in MCYR-exposed animals compared to the nonexposed control ones was observed in brain (2.5 fold), liver (2.1 fold), kidney medulla (1.9 fold), kidney cortex (1.8 fold) and lung (1.7 fold) cells, while the DNA from lymphocytes and spleen cells was not affected.<bold>Conclusion.</bold> This study demonstrated that subchronic exposure to sublethal doses of MCs can induce systemic genotoxicity in mammals, and it affects not only the liver but also other vital organs.</abstract>

Background. Microcystins (MCs) are cyclic heptapeptides that are considered to be liver specific toxins. They are potent tumour promoters and recent studies indicate that they are also genotoxic. In this study we measured DNA damage in lymphocytes, liver, kidney (cortex and medulla), lung, spleen and brain cells of male Fisher F344 rats that were exposed to sublethal dose (every second day 10 μg/kg b.w.; i.p) of micro-cystin-YR (MCYR) for one month.Methods. At the end of exposure the animals were sacrificed, the lymphocytes were isolated from blood taken from jugular vein, liver cells were obtained by perfusion with collagenase A and the cells from other organs were isolated by incubating small tissue pieces with collagenase A. The DNA damage in isolated cells was measured with the single cells gel electrophoresis (SCGE) also called the comet assay.Results. A significant increase of the % tail DNA in MCYR-exposed animals compared to the nonexposed control ones was observed in brain (2.5 fold), liver (2.1 fold), kidney medulla (1.9 fold), kidney cortex (1.8 fold) and lung (1.7 fold) cells, while the DNA from lymphocytes and spleen cells was not affected.Conclusion. This study demonstrated that subchronic exposure to sublethal doses of MCs can induce systemic genotoxicity in mammals, and it affects not only the liver but also other vital organs.

Subchronic exposure of rats to sublethal dose of microcystin-YR induces DNA damage in multiple organs

Department for Genetic Toxicology and Cancer Biology, National Institute of Biology, Ljubljana, Slovenia

Medical Faculty, Institute of Pathophysiology, University of Ljubljana, Ljubljana, Slovenia

Radiology and Oncology

Background. Microcystins (MCs) are cyclic heptapeptides that are considered to be liver specific toxins. They are potent tumour promoters and recent studies...

Subchronic exposure of rats to sublethal dose of microcystin-YR induces DNA damage in multiple organs

Published Online: Apr 30, 2007

Page range: 15 - 22

DOI: https://doi.org/10.2478/v10019-007-0003-z

Keywords
DNA damage, comet assay, cyanobacteria, bacterial toxins, rats, inbred F344

This content is open access.

Subchronic exposure of rats to sublethal dose of microcystin-YR induces DNA damage in multiple organs

Published Online: Apr 30, 2007

Page range: 15 - 22

DOI: https://doi.org/10.2478/v10019-007-0003-z

KeywordsDNA damage, comet assay, cyanobacteria, bacterial toxins, rats, inbred F344

This content is open access.

Keywords
DNA damage, comet assay, cyanobacteria, bacterial toxins, rats, inbred F344