Artemisolide is a typical inhibitor of IkappaB kinase beta targeting cysteine-179 residue and down-regulates NF-kappaB-dependent TNF-alpha expression in LPS-activated macrophages.
Nuclear factor (NF)-kappaB regulates a central common signaling for immunity and cell survival. Artemisolide (ATM) was previously isolated as a NF-kappaB inhibitor from a plant of Artemisia asiatica. However, molecular basis of ATM on NF-kappaB activation remains to be defined. Here, we demonstrate that ATM is a typical inhibitor of IkappaB kinase beta (IKKbeta), resulting in inhibition of lipopolysaccharide (LPS)-induced NF-kappaB activation in RAW 264.7 macrophages. ATM inhibited the kinase activity of highly purified IKKbeta and also LPS-induced IKK activity in the cells. Moreover, the effect of ATM on IKKbeta activity was completely abolished by substitution of Cys-179 residue of IKKbeta to Ala residue, indicating direct targeting site of ATM. ATM could inhibit IkappaBalpha phosphorylation in LPS-activated RAW 264.7 cells and subsequently prevent NF-kappaB activation. Further, we demonstrate that ATM down-regulates NF-kappaB-dependent TNF-alpha expression. Taken together, this study provides a pharmacological potential of ATM in NF-kappaB-dependent inflammatory disorders.
College of Pharmacy, Chungbuk National University, Cheongju 361-763, Republic of Korea.
Byung Hak
BH
Kim
Jun-Young
JY
Lee
Jee Hee
JH
Seo
Hwa Young
HY
Lee
Shi Yong
SY
Ryu
Byung Woo
BW
Ahn
Chong-Kil
CK
Lee
Bang Yeon
BY
Hwang
Sang-Bae
SB
Han
Youngsoo
Y
Kim
D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D003545:Cysteine / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D051550:I-kappa B Kinase / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D010766:Phosphorylation; D015398:Signal Transduction; D014315:Triterpenes / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*
D000893:Anti-Inflammatory Agents; D004791:Enzyme Inhibitors; D008070:Lipopolysaccharides; D016328:NF-kappa B; D014315:Triterpenes; D014409:Tumor Necrosis Factor-alpha; C513233:artemisolide; D051550:I-kappa B Kinase; D003545:Cysteine