Inhalation of Molecular Hydrogen, a Rescue Treatment for Noise-Induced Hearing Loss
Fransson AE, Videhult Pierre P, Risling M, Laurell GFE. · Frontiers in cellular neuroscience. 2021;15:658662.
What kind of evidence is this?
Preclinical
Controlled animal and cell study
Other neurological conditions
Inhaled H₂
Not reported in this record.
Not reported in this record.
Methods at a glance
guinea pigs, cell, cells, tissues used to study other neurological conditions.
Preclinical study; group or assay counts reported in the full text include n=8.
1 week
Full text reports inhaled H₂-containing gas. Detected intervention quantities or schedules: 1 week, 2 weeks, 0.3%, 10 min, 45 min, 12 mm.
Inhaled molecular H₂; not classified as Brown’s gas without an H₂/O₂ composition.
H₂-related quantities reported in the intervention passages: 1 week, 2 weeks, 0.3%, 10 min, 45 min, 12 mm. Values are not combined across different experimental arms.
Not reported in the full article — an absolute H₂ flow in mL/min could not be verified.
O₂ concentration and absolute O₂ flow were not both reported in the full article; no value is inferred.
Control or comparison condition reported in the full article; see the linked methods for arm-specific details.
Outcomes and reported result
survival or mortality, clinical symptoms or functional scores, inflammation and cytokines, oxidative-stress and antioxidant markers, apoptosis or cell injury, metabolic laboratory measures
Article-reported result excerpt (24 words maximum): “Compared with the pre-measurements, both the Acute + H_2 and Acute + Air groups demonstrated significant threshold shifts of approximately 50–60 dB at all…” This excerpt is not a complete result summary; consult the linked full text for all positive and null findings.
The complete machine-readable article was checked for source identity, methods, intervention quantities, results, tables, funding and conflict declarations. This public record is based on the full article.
A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.
Cautions and applicability
Preclinical evidence only; findings do not establish a treatment effect in people. Funding or grant information is reported in the full article. The full article contains a conflict, commercial-support or supplied-product declaration; consult the source wording.
Applies to the reported animal, cell or tissue model, not directly to patients.
Not reported in this record.
Not reported in this record.
Not reported in this record.
No single-study GRADE certainty rating is assigned. Certainty is assessed by important outcome across a complete eligible evidence set, not by attaching a final grade to one source.
Sources and record status
PMID: 34140880 · DOI: 10.3389/fncel.2021.658662
A free full article is available through PubMed Central.
Official Europe PMC JATS full article and PubMed/PMC identifiers; structured full-text extraction and validation completed 8 August 2026.
2026-08-10