Effect of 5-O-Methylhirsutanonol on nuclear factor-kappaB-dependent production of NO and expression of iNOS in lipopolysaccharide-induced RAW264.7 cells.
Diarylheptanoids are known to have anti-inflammatory and anti-atherosclerotic activities in various cell types, including macrophages. 5- O-Methylhirsutanonol (5-MH) isolated from the leaves of Alnus japonica Steud exhibited the antioxidant activities on Cu (2+)- and AAPH-mediated low-density lipoprotein (LDL) oxidation in the thiobarbituric acid-reactive substances (TBARS) assay as well as the macrophage-mediated LDL oxidation. In the main study, we examined anti-inflammatory activities of 5- O-methylhirsutanonol (5-MH) on nuclear factor kappaB (NF-kappaB)-dependent nitric oxide (NO) production and expression of inducible nitric oxide synthease (iNOS) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages. 5-MH inhibited NO production with an IC 50 value of 14.5 microM and expression of both iNOS protein and iNOS mRNA in a parallel dose-response manner. Then, expression of inflammation-associated genes, such as TNF-alpha, COX-2, and IL-1beta, was suppressed by 5-MH, as determined by reverse transcriptase polymerase chain reaction analysis. Moreover, 5-MH attenuated NF-kappaB activation by inhibition of hyperphosphorylation of IkappaB-alpha and its subsequent proteolytic degradation and p65 nuclear translocation, as well as preventing DNA-binding ability. In addition, 5-MH suppressed the mRNA expression of the gene reactive oxygen species (ROS) concerned in the regulation of NF-kappaB signaling.
Han
Jong-Min
JM
National Research Laboratory of Lipid Metabolism and Atherosclerosis, System Proteomics Research Center, and Molecular Cancer Research Center, Korea.
Lee
Woo Song
WS
Kim
Ju-Ryoung
JR
Son
Joonsok
J
Kwon
Oh-Hyung
OH
Lee
Hyun-Jun
HJ
Lee
Jung Joon
JJ
Jeong
Tae-Sook
TS
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002460:Cell Line; D036381:Diarylheptanoids / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D016328:NF-kappa B / Q000494:pharmacology*; D009569:Nitric Oxide / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis
C527046:5-O-methylhirsutanonol; D000893:Anti-Inflammatory Agents; D036381:Diarylheptanoids; D008070:Lipopolysaccharides; D016328:NF-kappa B; D012333:RNA, Messenger; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II