Nitric oxide and MCP-1 regulation in LPS activated rat Kupffer cells.
Nitric oxide (NO) and Monocyte Chemoattractant Protein (MCP)-1 co-regulation has been found in endotoxin-activated macrophages. Kupffer cells (KC) are a main source of soluble-mediators production in liver abnormalities. We investigated in vitro similar co-regulation of NO and MCP-1 production in rat activated KC. Isolated rat KC were cultured in the presence of 1 microg/ml LPS and various concentrations of Wortmannin (0-300 nM), L-NAME (0-500 microM) or MCP-1 (0-100 ng/ml). Production of MCP-1 and NO were measured in supernatants, by ELISA and a modification of the Griess reaction, respectively. Growth arrested KC, stimulated with vehicle, produced a basal amount of NO and MCP-1. In the presence of LPS, cultured KC secreted significantly (P < 0.01) increased amounts of MCP-1 and NO. Pre-treatment of KC with various concentrations of L-NAME significantly (P < 0.05) reduced the LPS-induced secretion of NO in a concentration dependent manner, but the MCP-1 production remained unaffected. Pre-treatment with Wortmannin significantly (P < 0.05) inhibited LPS-induced secretion of MCP-1 and NO in a concentration dependent manner. Linear regression analysis revealed a positive correlation between MCP-1 and NO in the LPS (r = 0.59171, P < 0.0001) and Wortmannin (r = 0.9215, P = 0.009) treated groups, but not in the L-NAME (r = -0.08513, P = 0.873). Incubation of KC with various concentrations of MCP-1 did not increase the NO production. These results indicate that KC might be the main source of NO and MCP-1 production in liver disorders, probably through the induction of PI3-kinase(s) and without any co-regulation between these molecules, which might represent two independent immunoregulatory pathways in the role of KC in hepatic disorders.
Kolios
George
G
Department of Gastroenterology, University of Crete, Greece. gkolios@med.uoc.gr
Valatas
Vassilis
V
Manousou
Pinelopi
P
Xidakis
Costas
C
Notas
George
G
Kouroumalis
Elias
E
D000730:Androstadienes / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000276:immunology / Q000378:metabolism* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D007728:Kupffer Cells / Q000276:immunology / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008107:Liver Diseases / Q000276:immunology / Q000378:metabolism; D008262:Macrophage Activation / Q000187:drug effects* / Q000276:immunology; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis* / Q000276:immunology; D019869:Phosphatidylinositol 3-Kinases / Q000276:immunology / Q000378:metabolism; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077191:Wortmannin
D000730:Androstadienes; C491766:Ccl2 protein, rat; D018932:Chemokine CCL2; D008070:Lipopolysaccharides; D010726:Phosphodiesterase Inhibitors; D009569:Nitric Oxide; D019869:Phosphatidylinositol 3-Kinases; D019331:NG-Nitroarginine Methyl Ester; D000077191:Wortmannin