Cruciferous phytoalexins:: antiproliferative effects in T-Jurkat leukemic cells

We tested antiproliferative activity of selected cruciferous phytoalexins including brassinin, 1-methoxybrassinin, (+/-)-spirobrassin, (+/-)1-methoxyspirobrassinin and (+/-)-1-methoxyspirobrassinol, in leukemic Jurkat cell. The most effective of the tested phytoalexins was Imethoxybrassinin with IC50 10 mu mol 1(-1). However, significant effect of all phytoalexines was also determined at concentration 1 mu mol 1(-1). In 1-methoxybrassinin-treated Jurkat cells, we found significant increase in the fraction of cells with a sub-G(0)/G(1) DNA content, which is considered to be a marker of cell death by apoptosis. Apoptosis was also confirmed by the annexin V staining. In summary, 1-methoxybrassinin exerted potent antiproliferative activity probably due to cell cycle arrest and apoptosis induction. (c) 2004 Elsevier Ltd. All rights reserved.