Cellular Signaling and Polyamines in the Control of Apoptosis in Intestinal Epithelial Cells

Abstract

A recent review article by Jänne et al. (1) begins with, “The polyamines, putrescine, spermidine, and spermine, are organic cations shown to participate in a bewildering number of cellular reactions, yet their exact functions in intermediary metabolism and specific interactions with cellular components remain largely elusive.” As documented by Schipper et al. (2) in their article entitled “Involvement of polyamines in apoptosis. Facts and controversies: effectors or protectors?” apoptosis or programmed cell death certainly belongs on the list. As the title of the Schipper et al. review indicates, the role of polyamines in apoptosis is anything but clear. In most, but not all instances, ornithine decarboxylase (ODC) activity increased with the induction of apoptosis, but there was no clear cut change in polyamine levels as they increased, decreased, or stayed the same depending on the system (2). Most experiments examining the effect of blocking ODC with α-difluoromethylornithine (DFMO) reported protection from apoptosis, whereas a few found no effect (2). The effects of polyamine analogs on apoptosis were also variable (2).KeywordsIntestinal Epithelial CellOkadaic AcidCrypt CellExecutioner CaspasesPolyamine AnalogThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.