Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0038358 (
gastric ulcer
)
5,179
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Helicobacter pylori infection is associated with the local production of chemokines and cytokines, of which IL-6 is overexpressed at the margin of
gastric ulcer
in H. pylori-positive gastritis. Cells of the monocytic lineage are the major sources of IL-6, and mononuclear cell infiltration in the lamina propria is characteristic of H. pylori-induced chronic infection. Our study shows for the first time that a secreted peptidyl prolyl cis-, trans-isomerase, HP0175 elicits IL-6 gene expression and IL-6 release from macrophages. An isogenic strain inactivated in the HP0175 gene (knockout) was attenuated in its IL-6-inducing ability, which was restored after complementation with the HP0175 gene. The specificity of the HP0175-induced effect was confirmed by the fact that rHP0175 purified from HEK293 cells could also induce IL-6 release, ruling out the possibility that the observed effect was due to bacterial contaminants. HP0175 was capable of interacting directly with the extracellular domain of TLR4. HP0175-induced IL-6 gene expression was critically dependent on TLR4-dependent NF-kappaB and MAPK activation. TLR4/PI3K-dependent ERK1/2 and p38 MAPK signaling converged upon activation of
mitogen- and stress-activated protein kinase 1
(
MSK1
). The central role of
MSK1
was borne out by the fact that silencing of
MSK1
expression abrogated HP0175-mediated NF-kappaB-dependent IL-6 gene transcription.
MSK1
regulated the recruitment of p65 and phopho-Ser(10)-histone H3 to the IL-6 promoter. HP0175 therefore regulated IL-6 gene transcription through chromatin modification at the IL-6 promoter.
...
PMID:TLR4-dependent NF-kappaB activation and mitogen- and stress-activated protein kinase 1-triggered phosphorylation events are central to Helicobacter pylori peptidyl prolyl cis-, trans-isomerase (HP0175)-mediated induction of IL-6 release from macrophages. 2647