Apoptosis plays a crucial role in maintenance of intestinal epithelial integrity and is highly regulated by numerous factors, including cellular polyamines. We recently showed that polyamines regulate nuclear factor (NF)-kappaB activity in normal intestinal epithelial (IEC-6) cells and that polyamine depletion activates NF-kappaB and promotes resistance to apoptosis. The current study went furt...

We previously showed that polyamines are required for proliferation and migration both in vivo and in a cultured intestinal epithelial cell (IEC-6) model. Wounding of the IEC-6 monolayer induced transient ERK activation, which was further enhanced by EGF. EGF stimulated migration in control and polyamine-depleted cells, but the degree of stimulation was significantly less in polyamine-depleted ...

This study was performed to determine if an alteration in vascular polyamine contents is associated with the development of deoxycorticosterone acetate-salt hypertension. The effects of chronic administration of alpha-difluoromethylornithine, a specific irreversible inhibitor of ornithine decarboxylase and thus polyamine biosynthesis, on vascular polyamine contents, structure, and function as w...

New drugs are urgently needed for the treatment of tropical and subtropical parasitic diseases, such as African sleeping sickness, Chagas' disease, leishmaniasis and malaria. Enzymes in polyamine biosynthesis and thiol metabolism, as well as polyamine transporters, are potential drug targets within these organisms. In the present review, the current knowledge of unique properties of polyamine m...

The polyamine-biosynthetic pathway represents an inviting target for the development of agents inhibiting carcinogenesis and tumor growth. Polyamines play an essential role in the proliferation and development of mammalian cells. Deranged polyamine metabolism may be an impor tant factor in carcinogenesis. Depletion of polyamines inhibits growth of neoplastic cells in vitro and in animal models....

The topoisomerase II inhibitor etoposide induced apoptosis in HL-60 cells within 4 h of exposure to the drug, as measured by changes in morphology, DNA fragmentation and cytotoxicity assays. Etoposide-induced apoptosis was accompanied by an increase in polyamine efflux from the cells and a decrease in total polyamine content during the first 24 h of exposure to the drug. Although both enzyme ac...

Receptor binding assays have shown that diaminodecane (DA-10) reduced binding of open channel blockers to the N-methyl-D-aspartate (NMDA) subtype of postsynaptic glutamate receptor through an interaction with the polyamine regulatory site. Because the action of DA-10 was opposite to that of the polyamine agonist spermine and was reversed by polyamine antagonists, DA-10 has been classified as an...

A selection of 21 rice cultivars (Oryza sativa L. ssp. indica and japonica) was characterized under moderate long-term drought stress by comprehensive physiological analyses and determination of the contents of polyamines and selected metabolites directly related to polyamine metabolism. To investigate the potential regulation of polyamine biosynthesis at the transcriptional level, the expressi...

The recently cloned and characterized human polyamine oxidase (PAOh1) potentially represents a new class of catabolic enzymes in the mammalian polyamine metabolic pathway capable of the efficient oxidation of polyamines. Here the discovery of three additional human PAO splice variants is reported, and the data support the fact that the human PAO gene codes for at least four isoenzymes, each of ...