Conjugated linoleic acids produced by Lactobacillus dissociates IKK-gamma and Hsp90 complex in Helicobacter pylori-infected gastric epithelial cells.
Although probiotics have been reported to reduce the gastric inflammatory response to Helicobacter pylori infection, little information is available regarding the molecular mechanisms behind this reduction. This study investigates the role of conjugated linoleic acids (CLA) produced by probiotics in interactions of IkappaB kinase (IKK) and heat shock protein 90 (Hsp90) to activate the nuclear factor-kappaB (NF-kappaB) signaling pathway in human gastric epithelial cells infected with H. pylori. Conditioned medium (CM) containing Lactobacillus acidophilus-producing CLA significantly inhibited the activated NF-kappaB signals and the upregulated expression of interleukin-8 (IL-8) in MKN-45 cells infected with H. pylori. Pretreatment with CM with CLA attenuated the increased IKK activity induced by H. pylori. Transfection of siRNA for IKK-beta dramatically reduced H. pylori-induced IkappaBalpha phosphorylation, but siRNA for IKK-alpha had little effect on IkappaBalpha phosphorylation, although the siRNA for IKK-alpha significantly decreased IL-8 production. Furthermore, Hsp90 was associated with IKK-alpha and IKK-gamma in H. pylori-infected cells, and CM with CLA dissociated the complex between Hsp90 and IKK-gamma. These results suggest that CLA produced by probiotics has anti-inflammatory activity in gastric epithelial cells infected with H. pylori via dissociation of the IKK-gamma and Hsp90 complex.
Kim
Jung M
JM
Department of Microbiology, Hanyang University College of Medicine, Seoul, South Korea. jungmogg@hanyang.ac.kr
Kim
Joo S
JS
Kim
Yeong J
YJ
Oh
Yu K
YK
Kim
In Y
IY
Chee
Young J
YJ
Han
Joong S
JS
Jung
Hyun C
HC
D002460:Cell Line; D004789:Enzyme Activation / Q000187:drug effects; D005753:Gastric Mucosa / Q000378:metabolism* / Q000473:pathology; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism*; D016481:Helicobacter Infections / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D051550:I-kappa B Kinase / Q000235:genetics / Q000378:metabolism*; D016209:Interleukin-8 / Q000037:antagonists & inhibitors; D007778:Lactobacillus / Q000378:metabolism*; D044243:Linoleic Acids, Conjugated / Q000096:biosynthesis / Q000494:pharmacology*; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D034741:RNA, Small Interfering / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects
D018841:HSP90 Heat-Shock Proteins; D016209:Interleukin-8; D044243:Linoleic Acids, Conjugated; D016328:NF-kappa B; D034741:RNA, Small Interfering; D051550:I-kappa B Kinase