In vitro metabolism and toxicity assessment of toxin T-514 (Peroxisomicine A1) of Karwinskia humboldtiana in microsomes and primary cultured hepatocytes

Toxicity and Anticancer Potential of Karwinskia: A Review

Karwinskia genus consists of shrubs and small trees. Four toxic compounds have been isolated from Karwinskia plants, which were typified as dimeric anthracenones and named T496, T514, T516, and T544. Moreover, several related compounds have been isolated and characterized. Here we review the toxicity of the fruit of Karwinskia plants when ingested (accidentally or experimentally), as well as the toxicity of its isolated compounds. Additionally, we analyze the probable antineoplastic effect of T514. Toxins cause damage mainly to nervous system, liver, lung, and kidney. The pathophysiological mechanism has not been fully understood but includes metabolic and structural alterations that can lead cells to apoptosis or necrosis. T514 has shown selective toxicity in vitro against human cancer cells. T514 causes selective and irreversible damage to peroxisomes; for this reason, it was renamed peroxisomicine A1 (PA1). Since a significant number of malignant cell types contain fewer peroxisomes than normal cells, tumor cells would be more easily destroyed by PA1 than healthy cells. Inhibition of topoisomerase II has also been suggested to play a role in the effect of PA1 on malignant cells. More research is needed, but the evidence obtained so far indicates that PA1 could be an effective anticancer agent.

Synthesis, crystal structures and cytotoxicities of some transition metal complexes with N-[2-{(pyridin-2-ylmethylidene)amino}ethyl]acetamide

The synthesis and spectroscopic (IR, (1)H and (13)C NMR) characterization of new complexes of Pt(II), Pd(II), Cu(II), and Hg(II) with the Schiff base ligand MeCONHCH(2)CH(2)N=CHPy (L) (Py=pyridine) are reported, together with studies on the cytotoxicities of these complexes, L and [ReBr(CO)(3)(L)] against human leukemia (MOLT-4), breast cancer (MCF-7) and Chang Liver (non-cancerous) cells. The crystal structures of [Pt(L)Cl(2)] (2), [Cu(L)Cl(2)] (4) and [Hg(L)Cl(2)](2) (5) are also reported. Of the complexes studied, [Cu(L)Cl(2)] (4) was identified as the most cytotoxic active derivative against cells of neoplastic origin (MOLT-4, and MCF-7), while having low toxicity on cells of benign origin (Chang Liver).