Anti-inflammatory activity of c-phycocyanin in lipopolysaccharide-stimulated RAW 264.7 macrophages.
C-phycocyanin (C-PC), found in blue green algae, is often used as a dietary nutritional supplement. C-PC has been found to have an anti-inflammatory activity and exert beneficial effect in various diseases. However, little is known about its mechanism of action. Overproduction of nitric oxide (NO) derived from inducible nitric oxide synthase (iNOS) plays an important role in the pathogenesis of inflammation. The aim of this study was to determine whether C-PC inhibits production of nitrite, an index of NO, and iNOS expression in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. Our results indicated that C-PC significantly inhibited the LPS-induced nitrite production and iNOS protein expression accompanied by an attenuation of tumor necrosis factor-alpha (TNF-alpha) formation but had no effect on interleukin-10 production in macrophages. Furthermore, C-PC also suppressed the activation of nuclear factor-kappaB (NF-kappaB) through preventing degradation of cytosolic IkappaB-alpha in LPS-stimulated RAW 264.7 macrophages. Thus, the inhibitory activity of C-PC on LPS-induced NO release and iNOS expression is probably associated with suppressing TNF-alpha formation and nuclear NF-kappaB activation, which may provide an additional explanation for its anti-inflammatory activity and therapeutic effect.
Cherng
Shiou-Chi
SC
Department of Nuclear Medicine, Tri-Service General Hospital, Taipei, Taiwan, ROC.
Cheng
Shin-Nan
SN
Tarn
Andrew
A
Chou
Tz-Chong
TC
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D015153:Blotting, Western; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D020672:I-kappa B Proteins / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism*; D010798:Phycocyanin / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D000893:Anti-Inflammatory Agents; D020672:I-kappa B Proteins; D008070:Lipopolysaccharides; D016328:NF-kappa B; D009573:Nitrites; D014409:Tumor Necrosis Factor-alpha; D010798:Phycocyanin; D000072000:NF-KappaB Inhibitor alpha; D052247:Nitric Oxide Synthase Type II