ANEUPLOIDOGENIC AND CLASTOGENIC POTENTIAL OF THE MYCOTOXINS CITRININ AND PATULIN

The aneuploidogenic and clastogenic potentials of the mycotoxins citri nin (CIT) and patulin (PAT) were studied by determining inhibition of microtubule assembly under cell-free conditions and by measuring induc tion of mitotic arrest and micronuclei in cultured Chinese hamster V79 cells. Both CIT and PAT inhibited cell-free microtubule polymerizatio n in a concentration-dependent manner. PAT, but not CIT, bound covalen tly to reactive thiol groups of microtubule proteins. At concentration s without gross cytotoxicity, mitotic arrest and CREST-positive micron uclei, i.e. micronuclei containing whole chromosomes/chromatids, were induced by CIT and PAT in V79 cells. The time course of micronucleus i nduction and positive CREST staining indicate the aneuploidogenic pote ntial of CIT and PAT. CREST-negative micronuclei, i.e. micronuclei con taining acentric chromosomal fragments, were induced by PAT but not by CIT, implying a clastogenic potential of PAT. The aneuploidogenic and clastogenic potential of PAT and the aneuploidogenic potential of CIT may well contribute to the putative carcinogenicity of these mycotoxi ns in long-term animal studies.