Polyamine metabolism and function

Abstract

Polyamines are ubiquitous organic cations of low molecular weight. The content of these amines is closely regulated by the cell according to the state of growth. The reactions responsible for the biosynthesis and interconversion of the polyamines and their precursor putrescine are described and the means by which polyamine content can be varied in response to exogenous stimuli are discussed. The role of polyamines in the cell cycle, cell division, tissue growth, and differentiation is considered. Recent studies using highly specific inhibitors of polyamine biosynthesis such as alpha-difluoromethylornithine to prevent accumulation of polyamines have indicated that the synthesis of polyamines is intimately associated with these processes. Such inhibitors have great potential for investigation of the cellular role of polyamines.

Polyamine patterns in the cerebrospinal fluid of patients with Parkinson's disease and multiple system atrophy

“…The lower concentration of spermidine and the higher concentration of the ratio of putrescine to spermidine in the PD group may explain the accumulation of putrescine and the reduced metabolic rate for spermidine biosynthesis from putrescine as a precursor of a deregulated metabolic pattern. Although the biochemical mechanisms responsible for these peculiar CSF PA profiles are unclear, disturbances in PA metabolism may be useful as potential biochemical diagnostic markers in patients with PD and MSA [6,18].…”

Influence of polyamines on membrane functions

“…Their roles in the regulation of major functions in cell growth, cell differentiation and their intricate and exquisitely regulated biosynthetic pathways have attracted considerable attention during the last few decades. Authoritative reviews and books have dealt with these aspects, including the design of enzyme inhibitors which by depleting cells of their normal polyamine contents provoke cell growth arrest and other pharmacologically important phenomena (see, e.g., Heby, 1981;Pegg & McCann, 1982;Tabor & Tabor, 1984;Pegg, 1986Pegg, , 1988McCann, e al., 1987). Although the functions attributed to the polyamines are numerous, their modes of action at a molecular level remain a matter of speculation.…”

Prostanoids, ornithine decarboxylase, and polyamines in primary chemoprevention of familial adenomatous polyposis

“…18 Ornithine decarboxylase (ODC) is the first and is a ratelimiting enzyme in the polyamine biosynthetic pathway. 18 In murine models of colorectal tumorigenesis, carcinogens induce ODC activity in colonic mucosa, and inhibitors of ODC suppress cancer development.…”

“…18 Ornithine decarboxylase (ODC) is the first and is a ratelimiting enzyme in the polyamine biosynthetic pathway. 18 In murine models of colorectal tumorigenesis, carcinogens induce ODC activity in colonic mucosa, and inhibitors of ODC suppress cancer development. [19][20][21][22][23] In human beings, ODC and polyamine levels are elevated in neoplasms compared with normal-appearing adjoining mucosa.…”