Augmentation of tumor necrosis factor-alpha-induced priming of fMet-Leu-Phe-stimulated neutrophils by pentoxifylline.
Tumor necrosis factor-alpha (TNF) is reported to cause tissue damage via enhanced neutrophil (PMNL) degranulation, superoxide production and altered PMNL migration. We investigated the effect of pentoxifylline (PTX) on TNF-induced respiratory burst activity of the PMNL. Since PTX has been reported to influence TNF-induced PMNL functions, our studies focused on the effects of timing and duration of the presence of PTX on superoxide anion production by PMNL exposed to TNF. When PMNL are exposed to PTX prior to priming with TNF and triggering with fMLP, respiratory burst activity was significantly enhanced by PTX, whereas the stimulatory effect of TNF was completely blunted by the continuous presence of PTX. Since free radical-scavenging properties of PTX have only recently been identified and may explain inhibitory effects on TNF-induced respiratory burst reported in the literature, our data for the first time suggests additive priming actions of PTX and TNF on PMNL respiratory burst activity.
Dunzendorfer
S
S
Department of Internal Medicine, University of Innsbruck, Austria.
Schratzberger
P
P
Reinisch
N
N
Kähler
C M
CM
Wiedermann
C J
CJ
D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D003594:Cytoplasmic Granules / Q000378:metabolism; D004357:Drug Synergism; D006801:Humans; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology*; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology; D010431:Pentoxifylline / Q000494:pharmacology*; D016897:Respiratory Burst / Q000187:drug effects; D013481:Superoxides / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D014409:Tumor Necrosis Factor-alpha; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; D010431:Pentoxifylline