Tumor necrosis factor and interleukin 1 activate phospholipase in rat chondrocytes.
Tumor necrosis factor (TNF) and interleukin 1 (IL-1) are both cytokines of macrophage origin with similar activity on several cell types. We investigated whether TNF can, analogously to IL-1, stimulate phospholipase activity of chondrocytes. Addition of each of these cytokines to cells, isolated from the xiphisternum of adult rats, resulted in a time- and dose-dependent increase in phospholipase activity in both secreted and membrane-associated form. Moreover, TNF and IL-1 both induce a transformation of chondrocyte morphology. In conclusion, TNF stimulates chondrocyte phospholipase activity and extends the long list of actions shared by IL-1 and TNF in a diversity of cellular systems.
Suffys
P
P
Laboratory of Molecular Biology, State University of Ghent, Belgium.
Van Roy
F
F
Fiers
W
W
D000818:Animals; D002356:Cartilage / Q000166:cytology / Q000201:enzymology*; D002478:Cells, Cultured; D004789:Enzyme Activation / Q000187:drug effects; D007375:Interleukin-1 / Q000494:pharmacology*; D010740:Phospholipases / Q000378:metabolism*; D010741:Phospholipases A / Q000378:metabolism; D051381:Rats; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D007375:Interleukin-1; D014409:Tumor Necrosis Factor-alpha; D010740:Phospholipases; D010741:Phospholipases A