Effects of vitamin E on fibroblast fibronectin

Fibronectin is a glycoprotein found mainly on fibroblast cell surfaces. Cultured human skin fibroblasts grow as monolayers in regular linear and whorl-shaped patterns. Exposure to a certain vitamin E analogue, D-alpha-tocopheryl-polyethylene-glycol-1000-succinate, induces concentration-dependent morphological and pattern changes. Using indirect immunofluorescence techniques, fibronectin, a cell protein associated with cell structure and intercellular patterns, was identified within the cells and the intercellular spaces. At a low concentration, the vitamin E analogue caused inhibition of the intercellular distribution of fibronectin without changes in intracellular fibronectin or significant disruption of the morphological patterns. At higher concentrations morphological changes ensued. These data suggest that the mechanism of vitamin E-induced morphological and intercellular pattern changes may not be manifested through inhibition of fibronectin deposition or secretion.