Oral Administration of Cyanobacterial Bloom Extract Induced the Altered Expression of the PP2A, Bax, and Bcl-2 in Mice

The frequent occurrences of the toxic cyanobacterial (specifically Microcystis aeruginosa) bloom are becoming a global environmental issue. Lots of researches have been focused on the pure cyanobacterial toxins, but little on the natural cyanobacterial bloom. This study was undertaken to investigate the effect of the natural cyanobacterial bloom extract on the expression of proteins, which have been shown to be affected by pure microcystins. In current study, the cyanobacterial bloom extract has been administered orally to ICR mice for 7 days with different dosages. The expression level of PP2A, Bcl-2, and Bax was measured via western blotting. The results showed that after 7 days of exposure to cyanobacteria extract, in mice liver tissue, the expression level of PP2A and Bax was increased significantly between the control and treatment groups, but there is no significant change on the Bcl-2 expression. This is the first report to describe the altered expression of PP2A in vivo when mice exposure to natural water blooms extract that means many cellular pathways would be interfered via the change of PP2A activity. (C) 2008 Wiley Periodicals, Inc. Environ Toxicol 23: 688-693, 2008.