TY - JOUR
T1 - Effects of Helicobacter pylori and Nitrate-Reducing Bacteria Coculture on Cells
AU - Ojima, Hinako
AU - Kuraoka, Sakiko
AU - Okanoue, Shyoutarou
AU - Okada, Hiroyuki
AU - Goto, Kazuyoshi
AU - Matsushita, Osamu
AU - Watanabe, Akari
AU - Yokota, Kenji
N1 - Funding Information:
This study is supported by Japan society for the promotion of science, Grant-in Aid for Scientic Reserch ©, Grant Number 21K07336 to K. Yokota.
Publisher Copyright:
© 2022 by the authors.
PY - 2022/12
Y1 - 2022/12
N2 - Helicobacter pylori infection is an important risk factor for developing gastric cancer. However, only a few H. pylori-infected people develop gastric cancer. Thus, other risk factors aside from H. pylori infection may be involved in gastric cancer development. This study aimed to investigate whether the nitrate-reducing bacteria isolated from patients with atrophic gastritis caused by H. pylori infection are risk factors for developing atrophic gastritis and gastric neoplasia. Nitrate-reducing bacteria were isolated from patients with atrophic gastritis caused by H. pylori infection. Among the isolated bacteria, Actinomyces oris, Actinomyces odontolyticus, Rothia dentocariosa, and Rothia mucilaginosa were used in the subsequent experiments. Cytokine inducibility was evaluated in monocytic cells, and mitogen-activated protein kinase (MAPK) activity and cell cycle were assessed in the gastric epithelial cells. The cytotoxicities and neutrophil-inducing abilities of the Actinomyces and Rothia species were enhanced when cocultured with H. pylori. Th1/Th2-related cytokines were also expressed, but their expression levels differed depending on the bacterial species. Moreover, H. pylori and Actinomyces activated MAPK (ERK and p38) and affected cell cycle progression. Some nitrate-reducing bacteria cocultured with H. pylori may promote inflammation and atrophy by inducing cytokine production. In addition, the MAPK activation and cell cycle progression caused by these bacteria can contribute to gastric cancer development.
AB - Helicobacter pylori infection is an important risk factor for developing gastric cancer. However, only a few H. pylori-infected people develop gastric cancer. Thus, other risk factors aside from H. pylori infection may be involved in gastric cancer development. This study aimed to investigate whether the nitrate-reducing bacteria isolated from patients with atrophic gastritis caused by H. pylori infection are risk factors for developing atrophic gastritis and gastric neoplasia. Nitrate-reducing bacteria were isolated from patients with atrophic gastritis caused by H. pylori infection. Among the isolated bacteria, Actinomyces oris, Actinomyces odontolyticus, Rothia dentocariosa, and Rothia mucilaginosa were used in the subsequent experiments. Cytokine inducibility was evaluated in monocytic cells, and mitogen-activated protein kinase (MAPK) activity and cell cycle were assessed in the gastric epithelial cells. The cytotoxicities and neutrophil-inducing abilities of the Actinomyces and Rothia species were enhanced when cocultured with H. pylori. Th1/Th2-related cytokines were also expressed, but their expression levels differed depending on the bacterial species. Moreover, H. pylori and Actinomyces activated MAPK (ERK and p38) and affected cell cycle progression. Some nitrate-reducing bacteria cocultured with H. pylori may promote inflammation and atrophy by inducing cytokine production. In addition, the MAPK activation and cell cycle progression caused by these bacteria can contribute to gastric cancer development.
KW - cell cycle
KW - Helicobacter pylori
KW - IL-8
KW - nitrate-reducing bacteria
KW - TNF-α
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U2 - 10.3390/microorganisms10122495
DO - 10.3390/microorganisms10122495
M3 - Article
AN - SCOPUS:85144645416
SN - 2076-2607
VL - 10
JO - Microorganisms
JF - Microorganisms
IS - 12
M1 - 2495
ER -
