# Stimulation of human damaged sperm motility with hydrogen molecule.
> 水素分子による損傷ヒト精子運動性の改善に関する研究


## Abstract

Sperm motility is a key determinant of male fertility, and its reduction can result from oxidative damage, abnormal spermatogenesis, or intracellular ATP depletion. This in vitro study examined the influence of molecular hydrogen (H2) on human sperm with experimentally impaired motility, using samples either stored at room temperature for more than 5 days or subjected to freeze-thaw cycles. H2 exposure significantly elevated the rate of forward motility, while nitrogen gas exposure produced no comparable effect. A 30-minute exposure was sufficient to achieve improvement, and re-exposure after 24 hours restored motility gains. Swimming speed was not altered by H2. Mitochondrial membrane potential was elevated following H2 exposure, suggesting involvement of mitochondrial energy metabolism. Frozen-thawed sperm cultured in H2-containing cleavage medium also showed significant motility recovery. These findings indicate that H2 may offer a useful approach for addressing low sperm motility associated with oxidative stress.

### Mechanism

H2 is thought to selectively neutralize harmful reactive oxygen species, thereby restoring mitochondrial membrane potential and improving forward motility in damaged sperm.

## Bibliographic

- **Authors**: Nakata K, Yamashita N, Noda Y, Ohsawa I
- **Journal**: Med Gas Res
- **Year**: 2015
- **PMID**: [25649433](https://pubmed.ncbi.nlm.nih.gov/25649433/)
- **DOI**: [10.1186/s13618-014-0023-x](https://doi.org/10.1186/s13618-014-0023-x)
- **PMC**: [PMC4300028](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4300028/)
- **Study type**: in vitro study
- **Delivery route**: in vitro
- **Effect reported**: positive

## Delivery context

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).

## Safety notes

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices 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 25649433. https://h2-papers.org/en/papers/25649433
> **Source**: PubMed PMID [25649433](https://pubmed.ncbi.nlm.nih.gov/25649433/)