Modulation of intercellular communication mediated at the cell surface and on extracellular, plasma membrane-derived vesicles by ionizing radiation
Document Type
Article
Publication Title
Experimental hematology
Abstract
The plasma membrane is a dynamic organelle whose function includes receptor-mediated signal transduction into the cell. Conversely, the plasma membrane is the origin of inter-cellular signaling. In addition to expressing and releasing growth factors in a soluble form(through exocytosis) and via proteolysis of cell surface components, membrane ligands may signal nearby cells through juxtacrine stimulation or by the exfoliation or shedding of plasma membrane-derived vesicles. Ionizing radiation (IR) has a profound effect on plasma membrane structure and function. IR-induced ultrastructural alterations are mediated via lipid interaction with water radiolysis products (e.g., hydroxyl radicals, hydrogen radicals, and hydrated electrons). Ionizing radicals act directly on lipid molecules to promote lipid hydro-peroxides and lipid hydroperoxide breakdown products (e.g., alpha, beta unsaturated aldehydes) that contribute to altered plasma membrane lipid composition. A change in lipid composition increases membrane lipid microviscosity and results in membrane fenestrations that enhance permeability to small molecules and ions. Reactive ionizing species also stimulate sphingomyelinase activity, leading to sphingomyelin hydrolysis and ceramide generation that further contributes to altered membrane lipid composition and cellular apoptosis. In addition, exposure to IR results in impaired rate of and cumulative shedding of plasma membrane-associated growth factors. Mechanisms of exfoliation are reviewed for normal cells and the impact of radiation on modulating signal transduction mediated by exfoliation is summarized.
First Page
455
Last Page
64
DOI
10.1016/s0301-472x(03)00050-x
Publication Date
6-1-2003
Recommended Citation
Albanese, Joseph and Dainiak, Nicholas, "Modulation of intercellular communication mediated at the cell surface and on extracellular, plasma membrane-derived vesicles by ionizing radiation" (2003). All Research. 373.
https://scholar.bridgeporthospital.org/all_research/373
Identifier
12829020 (pubmed); 10.1016/s0301-472x(03)00050-x (doi); S0301472X0300050X (pii)