Wg. Jiang et al., REGULATION OF TIGHT JUNCTION PERMEABILITY AND OCCLUDIN EXPRESSION BY POLYUNSATURATED FATTY-ACIDS, Biochemical and biophysical research communications, 244(2), 1998, pp. 414-420
Tight junctions (TJ) are the topical most structure in epithelial and
endothelial cells and play a key role in the control of permeability a
nd prevention of tumour cell invasion of endothelium. In this study we
examined the effects of a range of polyunsaturated fatty acids on the
function of TJs and the expression of occludin, a key molecule in the
TJs of the human vascular endothelial cell line, ECV304. Treatment of
the endothelial cells with gamma linolenic acid, an anti-cancer PUFA,
increased the transendothelial cell resistance (TER) and reduced the
paracellular permeability to large molecules. The effects were seen wi
thout any changes in the viability of the endothelial cells. Occludin,
a recently identified molecule, which plays a major role in tight jun
ctions was up-regulated by this fatty acid as revealed by both Western
blotting and immunofluorescence. Other fatty acids were also tested.
Eicosapentaenoic acid (EPA) also exerted an up regulatory effect, but
LA and AA down-regulated the expression. We conclude that GLA and EPA
which also have other anti-cancer effects, regulate the expression of
occludin in endothelial cells and thus contribute to the modification
of the TER of these cells. (C) 1998 Academic Press.