How H. pylori Uses Hydrogen Gas to Spread Cancer-Causing Toxins in the Stomach
Hydrogen Metabolism in Helicobacter pylori Plays a Role in Gastric Carcinogenesis through Facilitating CagA Translocation
- Authors
- Ge Wang, Judith Romero-Gallo, Stéphane L. Benoit, M. Blanca Piazuelo, Ricardo L. Dominguez, Douglas R. Morgan, Richard M. Peek, Robert J. Maier
- Journal
- mBio
- Year
- 2016
- DOI
- 10.1128/mbio.01022-16
- Study Type
- Cell Culture
- Outcome
- Negative
- Peer Reviewed
- Yes
- Country
- United States
- Health Condition
- Gastric Cancer
- Body System
- Gastrointestinal
TL;DR
H. pylori hydrogenase activity promotes CagA toxin delivery and gastric carcinogenesis. Hydrogenase deletion eliminated gastric cancer development in infected gerbils (0% versus 50% in controls).
Key Finding
H. pylori strains with active hydrogenase enzymes were able to cause gastric cancer in 50% of infected gerbils, while strains with the hydrogenase genes removed caused cancer in none — and clinical strains from cancer patients showed significantly higher hydrogenase activity than those from gastritis patients.
Summary
This study examined how the stomach bacterium Helicobacter pylori uses hydrogen gas as an energy source and whether that process affects its ability to cause stomach cancer. Researchers found that a protein called hydrogenase — which allows H. pylori to 'burn' hydrogen for energy — helps the bacterium inject a cancer-promoting toxin (CagA) into stomach cells. When the hydrogenase genes were removed from the bacteria, the bacteria lost much of their ability to cause inflammation and cancer in gerbils. Importantly, this study is about hydrogen produced by bacteria inside the stomach, not hydrogen water consumed as a supplement.
Practical Takeaway
This research is about hydrogen metabolism by a disease-causing bacterium, not about drinking hydrogen water. It does not suggest any benefit or harm from hydrogen water consumption. People interested in hydrogen water should note this study is entirely unrelated to supplemental hydrogen intake and involves bacterial biology in cell cultures and animal models.
Abstract (excerpt)
A known virulence factor of Helicobacter pylori that augments gastric cancer risk is the CagA cytotoxin. A carcinogenic derivative strain, 7.13, that has a greater ability to translocate CagA exhibits much higher hydrogenase activity than its parent noncarcinogenic strain, B128. A Δhyd mutant…