N. Utoguchi et al., ASCORBIC-ACID STIMULATES BARRIER FUNCTION OF CULTURED ENDOTHELIAL-CELL MONOLAYER, Journal of cellular physiology, 163(2), 1995, pp. 393-399
The macromolecular permeability of cultured bovine aortic, bovine veno
us, and human umbilical vein endothelial cell monolayers was decreased
significantly in culture medium containing L-ascorbic acid (Asc Acid;
0.01-0.1 mM) and L-ascorbic acid 2-phosphate (Asc 2-P). Dithiothreito
l, which shows reducing activity equivalent to that of Asc Acid, did n
ot affect endothelial permeability. Asc Acid induced a sixfold increas
e in collagen synthesis by the endothelial cells. The coexistence of L
-azetidine 2-carboxylic acid, an inhibitor of collagen synthesis, atte
nuated the effect of Asc 2-P in a dose-dependent manner. Another colla
gen synthesis inhibitor, ethyl-3,4-dihydroxybenzoate, also inhibited c
ollagen synthesis and increased endothelial permeability. The decrease
in permeability of the endothelial monolayer was dependent on a reduc
tion of the permeability coefficient of the endothelial monolayer. The
se findings indicate that endothelial barrier function is stimulated b
y Asc Acid via an increase in collagen synthesis. (C) 1995 Wiley-Liss,
Inc.