An Immunohistochemical Study of the Increase in Antioxidant Capacity of Corneal Epithelial Cells by Molecular Hydrogen, Leading to the Suppression of Alkali-Induced Oxidative Stress.
Cejka C, Kossl J, Holan V, Zhang JH, Cejkova J. · Oxidative Medicine and Cellular Longevity. 2020;2020:7435260.
What kind of evidence is this?
Preclinical
Controlled rabbit study
Eye health
Other forms
Positive preclinical signal.
Animal eye tissue and biomarker outcomes.
Methods at a glance
Rabbit corneas exposed to an alkali-burn protocol.
30 rabbits initially; five per group were assessed after pretreatment and ten per group continued to alkali injury.
Three-day pretreatment with post-injury assessment.
Hydrogen-saturated phosphate-buffered saline applied to the cornea four times daily for three days before injury.
H2 dissolved in buffered saline; not Brown's gas.
1.5±0.2 ppm at preparation and approximately 0.8 ppm at corneal application.
Not applicable — topical solution.
No oxygen was co-delivered.
Phosphate-buffered saline without added hydrogen.
Outcomes and reported result
Corneal hydration, epithelial integrity, histology and oxidative-stress immunostaining.
Hydrogen-saline pretreatment was associated with less corneal damage and lower selected oxidative-stress markers after alkali injury.
The full article, methods, group flow, histology and immunostaining outcomes were checked.
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
Pretreatment animal model; it does not establish prevention or treatment effects in human eye injury.
The reported rabbit alkali-burn model.
SYRCLE animal-study tool — preliminary
Some concerns
Allocation and assessor blinding were not clearly reported.
Randomization/allocation reporting is limited · Blinding of personnel is unclear · Attrition is incompletely reported in places · Blinding of outcome assessors is unclear · No prospectively registered analysis plan identified
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: 32655773 · DOI: 10.1155/2020/7435260
Free full article in PubMed Central.
PubMed record and PubMed Central full text; extraction checked 9 August 2026.
2026-08-10