Genotoxicity of microcystic cyanobacteria extract of a water source in China.
The water pollution of toxic cyanobacteria (blue-green algae) is a worldwide problem and worsens with industrialization. Microcystins are potent cyclic heptapeptidic hepatotoxins produced mainly by Microcystis aeruginosa, and their hepatotoxicity has been well-documented. In contrast, information on the genotoxic effects of microcystins is relatively scarce. In our present study, the genotoxicity of microcystic cyanobacteria extract (MCE) of a water source in China was studied using Salmonella typhimurium assay (Ames test), comet assay (Single cell gel electrophoresis) and mouse micronucleus test. Results from Ames test indicated that MCE had strong mutagenicity regardless of the presence of S9. Moreover, MCE was able to induce DNA damage in primary cultured rat hepatocytes examined by comet assay. In addition, MCE also enhanced bone marrow micronucleated polychromatic erythrocytes in mice. The analysis of HPLC showed that the main component of MCE was microcystin-LR. The understanding of the potent genotoxicity of MCE will help to establish the possible link between water cyanobacteria contamination and high risk of primary liver cancer found in some endemic areas.
Center for Environmental and Occupational Health, Department of Community, Occupational and Family Medicine, MD3, National University of Singapore, Singapore 119260, Singapore.
W X
WX
Ding
H M
HM
Shen
H G
HG
Zhu
B L
BL
Lee
C N
CN
Ong
D000818:Animals; D001427:Bacterial Toxins / Q000633:toxicity*; D001853:Bone Marrow / Q000187:drug effects; D002273:Carcinogens / Q000633:toxicity*; D002681:China; D002851:Chromatography, High Pressure Liquid; D000458:Cyanobacteria / Q000737:chemistry*; D004249:DNA Damage / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004587:Electrophoresis, Agar Gel; D008099:Liver / Q000187:drug effects; D008297:Male; D051379:Mice; D052998:Microcystins; D009152:Mutagenicity Tests; D010456:Peptides, Cyclic / Q000633:toxicity*; D051381:Rats; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics; D014871:Water Microbiology
D001427:Bacterial Toxins; D002273:Carcinogens; D052998:Microcystins; D010456:Peptides, Cyclic; C078588:microcystin