Characterization of tumor necrosis factor alpha-induced alteration of glycosaminoglycans in cultured cells: comparison among vascular smooth-muscle cells, vascular endothelial cells, Chang liver cells and LLC-PK1 cells.

Abstract

We investigated the alteration of glycosaminoglycans (GAGs) induced by recombinant human tumor necrosis factor alpha (rhTNF alpha) using confluent cultures of bovine aortic smooth-muscle cells, bovine aortic endothelial cells, Chang liver cells and porcine kidney LLC-PK1 cells. It was found that the incorporation of both [35S]sulfate and [3H]glucosamine into GAGs in the trypsinate fraction of the cell layer was significantly decreased by rhTNF alpha in vascular smooth-muscle cells and vascular endothelial cells; the incorporation of [35S]sulfate was increased but that of [3H]glucosamine was unchanged in Chang liver cells; the incorporation of both [35S]sulfate and [3H]glucosamine was increased by rhTNF alpha in LLC-PK1 cells. In the conditioned medium, the incorporation of both [35S]sulfate and [3H]glucosamine was not greatly changed by rhTNF alpha in all tested cell types. Characterization of GAGs revealed that each cell type uniquely altered its GAGs after rhTNF alpha treatment; the cytokine-induced alteration of each GAG component was not necessarily the same among different cell types. It was therefore concluded that rhTNF alpha-induced alteration of GAGs is dependent upon cell type.