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Hydrogen Gas Inhalation Alleviates Airway Inflammation and Oxidative Stress on Ovalbumin-Induced Asthmatic BALB/c Mouse Model.

卵白アルブミン誘発喘息マウスモデルにおける水素ガス吸入による気道炎症および酸化ストレスの軽減

animal study inhalation positive 3%

Abstract

Allergic asthma, characterized by chronic airway inflammation, poses a significant global health burden. This animal study investigated the effects of 3% hydrogen gas inhalation in a BALB/c mouse model of ovalbumin (OVA)-induced allergic asthma. Thirty female mice were allocated to five groups: non-treatment, hydrogen-only, OVA-only negative control, OVA plus intranasal salbutamol positive control, and OVA plus inhaled hydrogen. Endpoints included differential white blood cell counts, lung histology, pro-inflammatory cytokines (IL-4, IL-5, IL-13, TNF-α, IFN-γ, GM-CSF, IL-10), oxidative stress markers (ROS, NO), antioxidant enzymes (GPx, catalase), and serum IgE. Hydrogen inhalation significantly reduced inflammatory cell infiltration, suppressed pro-inflammatory cytokine levels, enhanced antioxidant enzyme activity, and lowered serum IgE concentrations compared with the OVA-only control group.

Mechanism

Inhaled H2 scavenges reactive oxygen species and nitric oxide while upregulating glutathione peroxidase and catalase activity, thereby suppressing pro-inflammatory cytokines (IL-4, IL-5, IL-13, TNF-α) and reducing IgE-mediated allergic airway inflammation.

Bibliographic

Authors
He W, Rahman MH, Bajgai J, Abdul-Nasir S, Mo C, Ma HY, et al.
Journal
Antioxidants (Basel)
Year
2024 (2024-10-30)
PMID
39594470
DOI
10.3390/antiox13111328
PMC
PMC11591407

Tags

Disease:COPD / asthma (15) Delivery:inhalation delivery (196) Mechanism:antioxidant enzymes (423) hydroxyl radical scavenging (352) immune modulation (180) anti-inflammatory (743) oxidative stress (899) reactive oxygen species (774)

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.

→ Evidence by delivery route

Safety notes

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.

See also:

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