水素ガス吸入がマウスのストレス耐性に与える影響：うつ・不安様行動および神経内分泌応答の検討
Failure to adapt to stress can precipitate depressive and anxiety disorders. This animal study examined whether repeated inhalation of a hydrogen-oxygen mixed gas (67% H2 : 33% O2 by volume) could modify stress-related behavioral and neuroendocrine responses in mice. Across multiple behavioral assays—tail suspension, forced swimming, novelty-suppressed feeding, and open-field tests—hydrogen-oxygen inhalation significantly reduced both acute and chronic mild stress (CMS)-induced depressive- and anxiety-like behaviors. ELISA measurements revealed that the gas mixture prevented CMS-associated rises in serum corticosterone, adrenocorticotropic hormone, interleukin-6, and tumor necrosis factor-α. Notably, hydrogen exposure during adolescence produced lasting improvements in stress resilience that persisted into early adulthood. The authors propose that suppression of hypothalamic-pituitary-adrenal axis hyperactivation and attenuation of inflammatory signaling underlie these effects.
Hydrogen gas is proposed to enhance stress resilience by suppressing hypothalamic-pituitary-adrenal axis hyperactivation and reducing pro-inflammatory cytokine levels (IL-6 and TNF-α), thereby dampening both neuroendocrine and inflammatory responses to stress.
For inhalation applications of molecular hydrogen, the lower flammability limit (LFL) deserves careful handling. The classical 4% figure applies to closed-system mixtures; the practical inhalation-environment threshold is 10%. Even pure-hydrogen output (the UFL 75% paradox) passes through the flammable range at the air–gas boundary. High-concentration (66% / 100%) inhalers are documented in the Japanese Consumer Affairs Agency accident-information database and are not recommended.
See also:
https://h2-papers.org/en/papers/28852144