Uncaria rhynchophylla inhibits the production of nitric oxide and interleukin-1β through blocking nuclear factor κB, Akt, and mitogen-activated protein kinase activation in macrophages.
The stems with hook of Uncaria rhynchophylla have been used in traditional medicine as an antipyretic, antihypertensive, and anticonvulsant in China and Korea. In this study, we investigated the mechanism responsible for anti-inflammatory effects of U. rhynchophylla in RAW 264.7 macrophages. The aqueous extract of U. rhynchophylla inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and interleukin (IL)-1β secretion as well as inducible NO synthase (iNOS) expression, without affecting cell viability. Furthermore, U. rhynchophylla suppressed LPS-induced nuclear factor κB (NF-κB) activation, phosphorylation, and degradation of inhibitory protein IκB (IκB)-α, phosphorylation of Akt, extracellular signal-regulated kinase 1/2, p38 kinase, and c-Jun N-terminal kinase. These results suggest that U. rhynchophylla has the inhibitory effects on LPS-induced NO and IL-1β production in macrophages through blockade in the phosphorylation of Akt and mitogen-activated protein kinases, following IκB-α degradation and NF-κB activation.
Kim
Ji-Hee
JH
Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan, Republic of Korea.
Bae
Chang Hwan
CH
Park
Sun Young
SY
Lee
Sang Joon
SJ
Kim
YoungHee
Y
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects; D020672:I-kappa B Proteins / Q000378:metabolism; D053583:Interleukin-1beta / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D009569:Nitric Oxide / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors; D010936:Plant Extracts / Q000494:pharmacology*; D018547:Plant Stems / Q000737:chemistry; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors; D032070:Uncaria / Q000737:chemistry*
D000893:Anti-Inflammatory Agents; D020672:I-kappa B Proteins; D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D016328:NF-kappa B; C000606205:Nfkbia protein, mouse; D010936:Plant Extracts; D000072000:NF-KappaB Inhibitor alpha; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases