Induction of nitric oxide synthase in macrophages: inhibition by fructose-1,6-diphosphate.
Intravenous fructose-1,6-diphosphate (FDP) is reported to reverse shock and improves survival in animals given systemic lipopolysaccharide (LPS), although the mechanism is incompletely understood. Since endotoxin-related shock is associated with increased nitric oxide (NO) production, LPS-stimulated macrophages were treated with FDP, and the NO metabolite, nitrite, was measured 24 h later. Treatment of LPS-stimulated macrophages with 1, 5, or 10 mM FDP caused a dose-dependent reduction in mRNA expression for inducible NO synthase by Northern analysis and decreased the micromolar concentrations of nitrite produced by 17, 42, and 68%, respectively. Neither fructose nor sodium phosphate had these effects in LPS-exposed macrophages. Electrophoretic mobility shift assays revealed that FDP did not inhibit LPS-mediated activation of nuclear factor kappa B. Viability analysis showed that the FDP effect was not caused by cytotoxicity. Overall, these results suggest that fructose-1,6-diphosphate, a glycolytic intermediate with potential clinical use, may mitigate the adverse effects of LPS by regulating the generation of NO.
Edde
L
L
Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA.
Zhou
X
X
Eaton
J W
JW
Sherman
M P
MP
D000818:Animals; D015152:Blotting, Northern; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival; D002614:Chelating Agents / Q000494:pharmacology; D004396:Coloring Agents; D004790:Enzyme Induction; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005635:Fructosediphosphates / Q000494:pharmacology*; D015870:Gene Expression; D008070:Lipopolysaccharides / Q000494:pharmacology; D016676:Macrophages, Alveolar / Q000201:enzymology*; D016328:NF-kappa B / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites / Q000378:metabolism; D010710:Phosphates / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D014343:Trypan Blue
D002614:Chelating Agents; D004396:Coloring Agents; D004791:Enzyme Inhibitors; D005635:Fructosediphosphates; D008070:Lipopolysaccharides; D016328:NF-kappa B; D009573:Nitrites; D010710:Phosphates; D012333:RNA, Messenger; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D014343:Trypan Blue; C029063:fructose-1,6-diphosphate; D002118:Calcium