Laboratório de Genética Toxicológica, Departamento de Genética e Morfologia, Instituto de Ciências Biológicas, Universidade de Brasília, 70910-900 Brasília - DF, Brazil.
Toxicon. 2011 Sep 1;58(3):259-64. doi: 10.1016/j.toxicon.2011.06.005. Epub 2011 Jun 16.
Studies of genotoxicity in fish caused by cyanobacterial extracts containing microcystins (MCs) can be useful in determining their carcinogenic risk due to a genotoxic mechanism. An extract of cyanobacterial Microcystis ssp, containing MC-LR and -LA from a bloom collected in a eutrophic lake, showed genotoxicity to Oreochromis niloticus. DNA damage (comet assay) was significantly induced in peripheral erythrocytes with both tested concentrations of 6.90 μg kg(-1) bw and 13.80 μg kg(-1) bw through intraperitoneal injection (ip). There was no micronucleus induction after ip injection at concentrations of 6.90 μg kg(-1) bw and 13.80 μg kg(-1) bw. Body exposure resulted in micronucleus induction and DNA damage only at the highest tested concentrations of 103.72 μg L(-1). Thus, comet assay and ip injection revealed the highest levels of the genotoxicity of MCs. Apoptosis-necrosis test carried out at concentrations of 6.90 μg kg(-1) bw and 13.80 μg kg(-1) bw revealed that at low concentrations more apoptosis than necrosis occurred. At higher concentrations more necrosis than apoptosis occurred.
含有微囊藻毒素（MCs）的蓝藻提取物对鱼类的遗传毒性研究，由于遗传毒性机制，可以用于确定其致癌风险。从富营养化湖泊中采集的微囊藻属蓝藻的提取物，含有 MC-LR 和 -LA，对奥利亚罗非鱼具有遗传毒性。通过腹腔注射（ip），两种测试浓度（6.90μgkg(-1)bw 和 13.80μgkg(-1)bw）均显著诱导外周血红细胞中的 DNA 损伤（彗星试验）。在浓度为 6.90μgkg(-1)bw 和 13.80μgkg(-1)bw 时，ip 注射后没有诱导微核。在最高测试浓度 103.72μgL(-1)时，仅暴露于体内会导致微核诱导和 DNA 损伤。因此，彗星试验和 ip 注射揭示了 MCs 的最高遗传毒性水平。在浓度为 6.90μgkg(-1)bw 和 13.80μgkg(-1)bw 时进行的凋亡-坏死试验表明，在低浓度下，凋亡比坏死发生更多。在更高的浓度下，坏死比凋亡发生更多。
