# Molecular hydrogen ameliorates lipopolysaccharide-induced acute lung injury in mice through reducing inflammation and apoptosis.
> リポ多糖誘発急性肺傷害マウスモデルにおける水素ガスの炎症・アポトーシス抑制効果


## Abstract

Acute lung injury (ALI) remains a critical contributor to mortality in intensive care settings. This mouse study examined the effects of 2% H2 gas inhalation (administered for 1 hour at 1 and 6 hours post-LPS challenge) and intraperitoneal hydrogen-rich saline (10 mL/kg) in an intratracheal LPS-induced ALI model. Both delivery routes improved histopathological scores, wet-to-dry weight ratio, oxygenation index (PaO2/FiO2), and total protein levels in bronchoalveolar lavage fluid (BALF). H2 suppressed both early and late pulmonary NF-κB activation. Apoptosis was reduced, as indicated by fewer TUNEL-positive cells and lower caspase-3 activity. Neutrophil infiltration, myeloperoxidase activity, and concentrations of proinflammatory cytokines (TNF-α, IL-1β, IL-6, HMGB1) and chemokines (KC, MIP-1α, MIP-2, MCP-1) in BALF were all markedly decreased. These findings indicate that molecular hydrogen mitigates LPS-induced ALI by attenuating NF-κB-mediated inflammatory and apoptotic responses.

### Mechanism

H2 suppresses both early and late NF-κB activation in lung tissue, thereby reducing proinflammatory cytokine and chemokine production, neutrophil recruitment, and caspase-3-dependent apoptosis in LPS-challenged mice.

## Bibliographic

- **Authors**: Xie K, Yu Y, Huang Y, Zheng L, Li J, Chen H, et al.
- **Journal**: Shock
- **Year**: 2012
- **PMID**: [22508291](https://pubmed.ncbi.nlm.nih.gov/22508291/)
- **DOI**: [10.1097/SHK.0b013e31824ddc81](https://doi.org/10.1097/SHK.0b013e31824ddc81)
- **Study type**: animal study
- **Delivery route**: mixed routes
- **Effect reported**: positive
- **H2 concentration**: 2%

## Delivery context

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

## Safety notes

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

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> **Cite as**: H2 Papers — PMID 22508291. https://h2-papers.org/en/papers/22508291
> **Source**: PubMed PMID [22508291](https://pubmed.ncbi.nlm.nih.gov/22508291/)