抄録
T-2 toxin is a cytotoxic fungal secondary metabolite produced by various species of Fusarium. This paper reviews the reported data about the development and/or mechanisms of T-2 toxin-induced apoptosis in the hematopoietic, lymphoid and gastrointestinal tissues, dorsal skin and fetal tissues of mice and rats. Apoptosis occurs earlier in hematopoietic tissues than in lymphoid tissues, and moreover there is a difference among lymphocyte populations in the susceptibility to T-2 toxin. C-fos plays an important role in the early phase of T-2 toxin-induced apoptosis in hematopoietic and lymphoid tissues through mobilization of [Ca2+]i and the PKC-dependent pathway, but not through Fas/Fasligand or p53-related pathways. In the gastrointestinal tract, apoptosis develops earlier in the small intestine than in the stomach, and is more prominent in the small intestine than in the large intestine. In the dorsal skin topically treated with T-2 toxin, epidermal basal cell proliferating activity is first suppressed due to the elevated TGF-β1 expression, and then basal cell apoptosis develops concomitantly with the elevation of c-fos, c-jun and TNF- α mRNAs expression. In the fetuses, T-2 toxin-induced apoptosis is mainly observed in the central nervous and skeletal systems. In the fetal brain, T-2 toxin induces oxidative stress, followed by activation of the MAPK-JNK-c-Jun pathway, finally resulting in apoptosis. The TNF receptor pathway may also be involved in T-2 toxin-induced apoptosis in the fetal brain. Thus, the development and mechanisms of T-2 toxin-induced apoptosis differ somewhat depending on the tissues affected.
