In vitro effects of Helicobacter pylori-induced infection in gastric epithelial AGS cells on microglia-mediated toxicity in neuroblastoma SH-SY5Y cells.
OBJECTIVE
To investigate the in vitro effects of H. pylori-conditioned medium (HCM) from gastric epithelial AGS cell cultures on microglia and neuronal cells.


METHODS
H. pylori, human gastric epithelial AGS cells, microglia-like BV-2 cells and human neuroblastoma SH-SY5Y cells.


METHODS
Treated AGS cells with H. pylori at ratios from 1:100 to 1:900 for 24 h. Cultured BV-2 cells and SH-SY5Y cells were treated with HCM from AGS cell cultures.


METHODS
Cell viability was measured by a quantitative colorimetric assay with MTT. Nitric oxide (NO) was determined by using Griess reagent. IL-8 was measured by an enzyme-linked immunosorbent assay. Protein expressions were revealed by western blot analysis.


RESULTS
H. pylori increased IL-8, NO, COX-2 and gp91(phox) in AGS cell cultures. When BV-2 cells were cocultured with AGS cells, HCM increased COX-2, gp91(phox), iNOS and NO of BV-2 cells. HCM also enhanced the degradation of I kappaB alpha in BV-2 cells. HCM up-regulated expression of nNOS, COX-2, and gp91(phox) of SH-SY5Y cells co-cultured with BV-2 cells. Particularly, the decrease of cell viability of SH-SY5Y induced by HCM was dependent on the presence of BV-2 cells.


CONCLUSIONS
H. pylori-induced infection induces microglia-mediated inflammation and neurotoxicity. The present results suggest that microglia play a critical role in HCM-induced toxicity of neuronal SH-SY5Y cells.
Lo
Yi-Ching
YC
Department of Pharmacology, Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung, 807, Taiwan. yichlo@kmu.edu.tw
Shih
Yu-Tzu
YT
Wu
Deng-Chyang
DC
Lee
Yi-Chern
YC
D002460:Cell Line; D002470:Cell Survival; D017077:Culture Media, Conditioned; D051546:Cyclooxygenase 2 / Q000378:metabolism; D004847:Epithelial Cells / Q000276:immunology; D005753:Gastric Mucosa / Q000276:immunology* / Q000382:microbiology; D016480:Helicobacter pylori / Q000276:immunology / Q000502:physiology*; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D017628:Microglia / Q000166:cytology / Q000276:immunology*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000276:immunology; D009569:Nitric Oxide / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism
C508606:CXCL8 protein, human; D017077:Culture Media, Conditioned; D016209:Interleukin-8; D008562:Membrane Glycoproteins; D009569:Nitric Oxide; C496320:NOS1 protein, human; D052248:Nitric Oxide Synthase Type I; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases