title: Asymmetric dimethylarginine regulates the lipopolysaccharide-induced nitric oxide production in macrophages by suppressing the activation of NF-kappaB and iNOS expression.
abstract: Two major effector systems are frequently implicated in the immune and endothelial cell alternations associated with inflammation. They include the enhanced production of reactive oxygen species and diminished bioavailability of nitric oxide (NO). Importantly, these processes can be regulated by endogenously produced methylarginines, inhibitors for NO derived from macrophages and endothelial cells. Therefore, the aim of this study was to show the potential pharmacological intervention of methylarginines (N(G)-methyl-L-arginine, L-NMMA; N(G), N(G)'-dimethyl-L-arginine-symmetric dimethylarginine, SDMA; and N(G), N(G)-dimethyl-L-arginine-asymmetric dimethylarginine, ADMA) in activation of murine peritoneal (RAW 264.7) and alveolar (MHS) macrophages with lipopolysaccharide from Gram-negative bacteria (LPS). The data presented in this study clearly declare that L-NMMA (1-50μM) and ADMA (10-50 μM) significantly inhibited the LPS-induced NO production from macrophages in a concentration-dependent manner. It was demonstrated, for the first time, that the ADMA- and L-NMMA-induced down regulation of NO production was accompanied by reduced expression of mRNA and protein for inducible NO synthase as well as decreased activation of nuclear factor-κB. Importantly, we found a negative correlation between the ADMA-dependent reduction of NO production and ADMA-increased superoxide formation, which indicates that ADMA can negatively affect the balance in LPS-induced macrophage-derived production of reactive mediators. The only effect of SDMA was observed for LPS-triggered superoxide production, which was significantly decreased in its highest concentration (50 μM). In summary, L-NMMA and ADMA can mediate their effects on macrophage activation via regulation of intracellular signaling pathways, which can affect critical functions in activated macrophages.
authors.affiliation: Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic. pekarovam@ibp.cz
authors.forename: Michaela
authors.initials: M
authors.lastname: Pekarova
authors.forename: Lukas
authors.initials: L
authors.lastname: Kubala
authors.forename: Hana
authors.initials: H
authors.lastname: Martiskova
authors.forename: Lucia
authors.initials: L
authors.lastname: Bino
authors.forename: Michaela
authors.initials: M
authors.lastname: Twarogova
authors.forename: Anna
authors.initials: A
authors.lastname: Klinke
authors.forename: Tanja K
authors.initials: TK
authors.lastname: Rudolph
authors.forename: Zdenka
authors.initials: Z
authors.lastname: Kuchtova
authors.forename: Hana
authors.initials: H
authors.lastname: Kolarova
authors.forename: Gabriela
authors.initials: G
authors.lastname: Ambrozova
authors.forename: Radek
authors.initials: R
authors.lastname: Kuchta
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Kadlec
authors.forename: Antonin
authors.initials: A
authors.lastname: Lojek
mesh_terms: D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D015153:Blotting, Western; D018929:Cell Culture Techniques; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D015870:Gene Expression / Q000187:drug effects; D008070:Lipopolysaccharides / Q000633:toxicity*; D016676:Macrophages, Alveolar / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D009569:Nitric Oxide / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013481:Superoxides / Q000378:metabolism
chemical_list: D008070:Lipopolysaccharides; D016328:NF-kappa B; C487735:dimethylarginine; C433788:lipopolysaccharide, E. coli O26-B6; D013481:Superoxides; D009569:Nitric Oxide; D001120:Arginine; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse