Dataset related to the article: "Cyclooxygenase-2 Glycosylation Is Affected by Peroxynitrite in Endothelial Cells: Impact on Enzyme Activity and Degradation"

This record containsraw data related to the article: "Cyclooxygenase-2 Glycosylation Is Affected by Peroxynitrite in Endothelial Cells: Impact on Enzyme Activity and Degradation"

Abstract: The exposure of human endothelial cells to 3-morpholinosydnonimine (SIN-1) induced the
expression of cyclooxygenase-2 (COX-2) in a dose- and time-dependent manner. Interestingly, after a
prolonged incubation (>8 h) several proteoforms were visualized by Western blot, corresponding
to different states of glycosylation of the protein. This effect was specific for SIN-1 that generates
peroxynitrite and it was not detected with other nitric oxide-donors. Metabolic labeling experiments
using 35S or cycloheximide suggested that the formation of hypoglycosylated COX-2 was dependent
on de novo synthesis of the protein rather than the deglycosylation of the native protein. Moreover,
SIN-1 reduced the activity of the hexokinase, the enzyme responsible for the first step of glycolysis.
The hypoglycosylated COX-2 induced by SIN-1 showed a reduced capacity to generate prostaglandins
and the activity was only partially recovered after immunoprecipitation. Finally, hypoglycosylated
COX-2 showed a more rapid rate of degradation compared to COX-2 induced by IL-1a and an
alteration in the localization with an accumulation mainly detected in the nuclear membrane. Our
results have important implication to understand the effect of peroxynitrite on COX-2 expression
and activity, and they may help to identify new pharmacological tools direct to increase COX-2
degradation or to inhibit its activity.