Anti-inflammatory activity of bark of Dioscorea batatas DECNE through the inhibition of iNOS and COX-2 expressions in RAW264.7 cells via NF-κB and ERK1/2 inactivation.
We identified a bioactive herbal medicine with anti-inflammatory activity from an ethanol extract derived from the bark of Dioscorea batatas DECNE (BDB) in RAW264.7 cells. We examined the effects of BDB on nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production in LPS-induced RAW264.7 cells. BDB consistently inhibited both NO and PGE(2) production in a dose-dependent manner, with an IC(50) of 87-71 μg/ml, respectively. The reduction of NO and PGE(2) production were accompanied by a reduction in iNOS and COX-2 protein expression, as evaluated by Western blotting. To evaluate the action mode of BDB and its ability to inhibit iNOS and COX-2 protein expression, we assessed the effects of BDB on nuclear factor-κB (NF-κB) DNA-binding activity, NF-κB-dependent reporter gene activity, inhibitory factor-κB (IκB) phosphorylation and degradation, and p65 nuclear translocation. BDB suppressed DNA-binding activity and reporter gene activity as well as translocation of the NF-κB p65 subunit. BDB also down-regulated IκB kinase (IKK), thus inhibiting LPS-induced both phosphorylation and the degradation of IκBα. In addition, BDB also inhibited the LPS-induced activation of ERK1/2.
Jin
Meihua
M
College of Pharmacy, Yeungnam University, Gyeongsan, Republic of Korea.
Suh
Seok-Jong
SJ
Yang
Ju Hye
JH
Lu
Yue
Y
Kim
Su Jeong
SJ
Kwon
Soonyoul
S
Jo
Tae Hyung
TH
Kim
Jin Wan
JW
Park
Young In
YI
Ahn
Ghe Whan
GW
Lee
Chong-Kil
CK
Kim
Cheorl-Ho
CH
Son
Jong-Keun
JK
Son
Kun Ho
KH
Chang
Hyeun Wook
HW
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000378:metabolism; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology*; D015232:Dinoprostone / Q000378:metabolism; D027742:Dioscorea / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects* / Q000201:enzymology; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010766:Phosphorylation; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology*
D052246:Cyclooxygenase 2 Inhibitors; D008070:Lipopolysaccharides; D016328:NF-kappa B; D010936:Plant Extracts; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D048049:Extracellular Signal-Regulated MAP Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D015232:Dinoprostone