title: Inhibition of Helicobacter pylori CagA-Induced Pathogenesis by Methylantcinate B from Antrodia camphorata.
abstract: The bacterial pathogen Helicobacter pylori (Hp) is the leading risk factor for the development of gastric cancer. Hp virulence factor, cytotoxin-associated gene A (CagA) interacted with cholesterol-enriched microdomains and leads to induction of inflammation in gastric epithelial cells (AGS). In this study, we identified a triterpenoid methylantcinate B (MAB) from the medicinal mushroom Antrodia camphorata which inhibited the translocation and phosphorylation of CagA and caused a reduction in hummingbird phenotype in HP-infected AGS cells. Additionally, MAB suppressed the Hp-induced inflammatory response by attenuation of NF-κB activation, translocation of p65 NF-κB, and phosphorylation of IκB-α, indicating that MAB modulates CagA-mediated signaling pathway. Additionally, MAB also suppressed the IL-8 luciferase activity and its secretion in HP-infected AGS cells. On the other hand, molecular structure simulations revealed that MAB interacts with CagA similarly to that of cholesterol. Moreover, binding of cholesterol to the immobilized CagA was inhibited by increased levels of MAB. Our results demonstrate that MAB is the first natural triterpenoid which competes with cholesterol bound to CagA leading to attenuation of Hp-induced pathogenesis of epithelial cells. Thus, this study indicates that MAB may have a scope to develop as a therapeutic candidate against Hp CagA-induced inflammation.
authors: Graduate Institute of Clinical Medical Science, China Medical University, Taichung 40402, Taiwan.
authors: Chun-Jung
authors: CJ
authors: Lin
authors: Yerra Koteswara
authors: YK
authors: Rao
authors: Chiu-Lien
authors: CL
authors: Hung
authors: Chun-Lung
authors: CL
authors: Feng
authors: Hsien-Yuan
authors: HY
authors: Lane
authors: David T W
authors: DT
authors: Tzeng
authors: Ping-Ning
authors: PN
authors: Hsu
authors: Chih-Ho
authors: CH
authors: Lai
authors: Yew-Min
authors: YM
authors: Tzeng