Fumonisin B1-induced apoptosis in neuroblastoma, glioblastoma and hypothalamic cell lines

Fumonisin B-1 (FB1) is a mycotoxin produced by Fusarium verticilliodes, which commonly infects corn across the world. Fusarium fungi may also be found in moisture-damaged buildings. In this study, we investigated the role of apoptosis in the toxicity of FBI in four different cell lines. Activation of caspase-3-like protease, DNA fragmentation and expression of p53 and Bcl-2 family proteins were studied in mouse GT1-7 hypothalamic, rat C6 glioblastoma, human U-118MG glioblastoma, and human SH-SY5Y neuroblastoma cells exposed to 0.1-100 mu M FBI for 0-144h. Caspase-3-like protease activity increased in all cell lines, except SH-SY5Y, at 48-144 h, and internucleosomal DNA fragmentation occurred in all of the cell lines, pointing to a role for apoptosis in the toxicity of FB1. However, the expressions of p53 or pro- or antiapoptotic Bcl-2 family proteins (Bax, Bcl-2, Bcl-X-L and Mcl-1) were not affected in any of the cell lines even after prolonged exposure to FBI at high doses. The results of this study, together with the results of our previous studies, provide evidence that FB1 is a potential neurotoxin, but that the toxicity of FB1 varies between different cell lines. The sensitivity of these cell lines towards FB1 is as follows: U-118MG > GT1-7 > C6 > SH-SY5Y cells. These results are consistent with the assumption that cells of glial origin may be more sensitive towards FB1 than cells of neural origin. (c) 2006 Elsevier Ireland Ltd. All rights reserved.