To elucidate the mechanisms underlying the toxicities of nivalenol (NIV) and deoxynivalenol (DON), their potencies on cell proliferation in cultured cells were investigated. Assays were performed after 24 h of treatment. Both toxins retarded proliferation of all 4 cell lines tested. NIV was more potent than DON in the human promyelocytic leukemia cell line HL60, the human lymphoblastic leukemia cell line MOLT-4, and the rat aortic myoblast cell line A-10. In contrast, both toxins exhibited almost the same potencies in the human hepatoblastoma cell line HepG2. If both toxins exert their toxicities through the same mechanism, ratios of the 50 % inhibitory concentration (IC_<50>) of DON to NIV are expected to be constant regardless of the types of cells used in the assays. However, the ratios of each IC_<50> varied, indicating differences in the mechanism of action of these toxins.
ニバレノール(NIV)とデオキシニバレノール(DON)の毒性発現機構を解明するために,培養細胞の増殖に対する両毒素の阻害効果を検討した.毒素処理24時間後に試験を行った.両毒素は試験に供した4つの培養細胞の増殖を遅らせた.ヒト前骨髄球白血病細胞HL60とヒトリンパ芽球白血病細胞MOLT-4,ラット大動脈筋芽細胞A-10においては,DON よりもNIV の方が効果が強かった.これに対し,ヒト肝芽腫細胞HepG2では両毒素ともほぼ同じ効果を示した.もし両毒素が同一の毒性発現機構で毒性を発揮しているのであれば,細胞の種類にかかわらずDON とNIV の50% 阻害濃度(IC_<50>)の比は一定になると考えられるが,各々の細胞のIC_<50>の比は一様でないことから,両毒素の毒性発現機構には違いがあると考えられた.