Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Farnesyl-L-cysteine analogs can inhibit or initiate superoxide release by human neutrophils
Ist Teil von
The Journal of biological chemistry, 1994-06, Vol.269 (24), p.16837-16844
Ort / Verlag
Bethesda, MD: American Society for Biochemistry and Molecular Biology
Erscheinungsjahr
1994
Quelle
MEDLINE
Beschreibungen/Notizen
A series of farnesylcysteine analogs was studied with respect to their abilities to interfere with fMet-Leu-Phe (fMLP)-stimulated
superoxide (O2-.) release by human neutrophils. Simple acyl derivatives of farnesyl-L-cysteine, such as the N-acetyl (L-AFC)
and N-isobutyryl derivatives (L-iBFC), which are substrates for the isoprenylated protein methyltransferase, can block O2-.
release. The N-butyryl analog (L-BFC), which is an isomer of L-iBFC and also a substrate for the methyltransferase, does not
inhibit O2-. release but actually stimulates it in the absence of fMLP. Other analogs, including the N-pivaloyl derivative,
which has been found to be neither a substrate nor an inhibitor of methyltransferase, also stimulate very large quantities
of O2-. production. The stimulatory effects of these derivatives are saturable and exquisitively sensitive to small structural
changes in the analogs. The signal transduction pathway(s) utilized by pivaloyl derivatives for triggering O2-. generation
is very similar to that employed by fMLP. These data make it clear that farnesyl-L-cysteine analogs do not produce their pharmacological
effects in neutrophils via methyltransferase blockade. This could be further demonstrated by showing that sinefungin and S-adenosylhomocysteine,
both powerful and general methyltransferase inhibitors which bind at the S-adenosylmethionine site, had no effect in preventing
the increased oxygen consumption associated with O2-. production in permeabilized neutrophils. These studies reveal that farnesyl-L-cysteine
analogs interact with a hitherto undefined target in neutrophils that may be exploited for inhibiting or stimulating the inflammatory
or antimicrobial responses of these cells.