Hydrogen Gas Therapy Attenuates Inflammatory Pathway Signaling in Septic Mice.
敗血症マウスにおける水素ガス吸入による炎症シグナル経路の抑制
Abstract
Using a cecal ligation and puncture (CLP) sepsis model in 9-week-old male C57BL/6 mice, this study examined the effects of continuous 7% H2 gas inhalation on survival, systemic inflammation, and multi-organ gene expression. The 7-day survival rate reached 75% in H2-inhaled mice versus 40% in controls (P < 0.05). Serum interleukin-6 and tumor necrosis factor-α concentrations were reduced at 24 hours post-CLP, and blood glucose levels were better maintained in H2-exposed animals. RNA sequencing of liver, intestine, and lung tissue, analyzed via Ingenuity Pathway Analysis, revealed suppression of acute phase response signaling and STAT3 pathways in the liver and intestine. Upstream regulator genes including CD14 in the liver and multiple cytokine receptor genes in the intestine and lungs showed significantly decreased expression following H2 inhalation, providing mechanistic insight into how molecular hydrogen modulates the inflammatory cascade in sepsis.
Mechanism
H2 inhalation downregulates CD14 gene expression in the liver and cytokine receptor genes in the intestine and lungs, leading to inactivation of acute phase response signaling and the STAT3 pathway, thereby attenuating systemic inflammatory responses in septic mice.
Bibliographic
- Authors
- Matsuura H, Matsumoto H, Okuzaki D, Shimizu K, Ogura H, Ebihara T, et al.
- Journal
- J Surg Res
- Year
- 2021
- PMID
- 33639371
- DOI
- 10.1016/j.jss.2021.01.022
Tags
Delivery context
In air, molecular hydrogen is reported to be combustible across approximately **4% (LFL, lower flammability limit) to 75% (UFL, upper flammability limit)**. Among high-concentration hydrogen inhalers, 66% output sits inside this range, and even pure-hydrogen (100%) output forms a 4–75% concentration-gradient layer at the device–air boundary (the UFL 75% paradox). Engineering principle would therefore call for operation below LFL (the classical 4%); that figure, however, was measured under closed, pre-mixed, static conditions. For the open, dynamic inhalation environment, the empirical value reported in the literature is **10%**, which is the figure referenced in practice as the operating ceiling. The 66% / 100% output devices are recorded in the Japanese Consumer Affairs Agency accident-information database, and from these considerations are not recommended.
Safety notes
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