Hydrogen gas alleviates oxygen toxicity by reducing hydroxyl radical levels in PC12 cells
Yu J, Yu Q, Liu Y, Zhang R, Xue L. · PLOS ONE. 2017;12(3):e0173645.
What kind of evidence is this?
Preclinical
Randomized four-condition PC12-cell normobaric/hyperbaric gas-exposure experiment
Other neurological conditions
Other forms
Not reported in this record.
Not reported in this record.
Methods at a glance
Rat pheochromocytoma PC12 cells exposed to normobaric air or five-atmosphere hyperbaric oxygen conditions.
Most assays report n=6 per condition and representative results from at least three experimental repeats; a single consolidated number of culture wells/cells is not given.
Three-hour total gas procedure; hyperbaric pressure held for two hours at 5 ATA.
Three-hour chamber exposure to 2% H₂ added either to normobaric air or to 98% O₂ at five atmospheres absolute.
Two H₂ mixtures: 2% H₂/20% O₂/78% N₂ at 1 ATA and 2% H₂/98% O₂ at 5 ATA — neither is Brown's gas.
Total chamber gas flow was 3 L/min. The hyperbaric protocol included slow compression/decompression and two hours at 5 ATA within a three-hour course.
60 mL/min H₂ in both H₂ groups, calculated from 3,000 mL/min × 2% H₂.
Normobaric H₂ group: 600 mL/min O₂ (20%); hyperbaric H₂ group: 2,940 mL/min O₂ (98%), both calculated from the reported 3 L/min total flow.
Normobaric air and 100% O₂ at 5 ATA, matched to the respective H₂ mixtures.
Outcomes and reported result
Cell viability, LDH, lipid and DNA oxidation, mitochondrial membrane measures and hydroxyl radical, superoxide, hydrogen peroxide and nitric-oxide fluorescence.
Under hyperbaric oxygen, H₂ favored viability, LDH, MDA, 8-OHdG and hydroxyl-radical measures. It did not significantly change superoxide, hydrogen peroxide or nitric oxide versus hyperbaric oxygen, and did not change viability/LDH/MDA/8-OHdG under normobaric air; one mitochondrial fluorescence measure did not differ.
The complete free PMC article, methods and figures were checked for exact gas mixtures, total flow and calculated component flows, pressure/timing, positive and null ROS/cell findings, funding and conflicts.
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
Cancer-derived cell line, nonclinical extreme hyperbaric exposure, many fluorescence endpoints, small laboratory replicates and no animal or human safety assessment. The National Natural Science Foundation of China funded the work; authors declared no competing interests.
PC12 cells exposed to hyperbaric oxygen; it does not establish an antioxidant adjunct for hyperbaric-oxygen 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: 28362819 · DOI: 10.1371/journal.pone.0173645
Free full article in PubMed Central.
Complete PMC article and PubMed metadata; full-text extraction checked 9 August 2026.
2026-08-10