Hydrogen Gas Shows Mixed Results for Eye Inflammation in Rats
- Authors
- Wei-Ming Yan, Tao Chen, Pan Long, Zhe Zhang, Qian Liu, Xiaocheng Wang, Jing An, Zuo-Ming Zhang
- Journal
- Medical Science Monitor
- Year
- 2018
- DOI
- 10.12659/MSM.907269
- Study Type
- Rat
- Outcome
- Neutral
- Peer Reviewed
- Yes
- Country
- China
- Health Condition
- Uveitis
- Body System
- Ocular
TL;DR
Breathing in hydrogen gas did not reduce the visible symptoms or cell infiltration in rat eye inflammation, but it did lower protein levels in eye fluid and slightly calm immune cells in the eye.
Key Finding
Hydrogen gas inhalation did not reduce clinical signs of eye inflammation or immune cell infiltration in rats, but it did lower aqueous humor protein concentration and reduce microglia activation.
Summary
Researchers induced eye inflammation in rats and then had some rats breathe hydrogen gas mixed with oxygen. While hydrogen gas did not reduce visible signs of inflammation or the number of immune cells in the eye, it did lower protein levels in the fluid inside the eye and reduced activation of a type of immune cell called microglia (which contribute to inflammation). This suggests hydrogen may have some anti-inflammatory effects at the cellular level, even though the overall clinical symptoms did not improve.
Practical Takeaway
This rat study suggests hydrogen gas may have some cellular anti-inflammatory effects, but these did not translate into visible clinical improvement. Because this is an animal study with a specific type of eye inflammation, it's unclear whether these findings would apply to humans or other conditions. More research would be needed before drawing conclusions about hydrogen's usefulness for inflammatory eye disease in people.
Abstract
BACKGROUND Molecular hydrogen (H2) has been widely reported to have benefiicial effects in diverse animal models and human disease through reduction of oxidative stress and inflammation. The aim of this study was to investigate whether hydrogen gas could ameliorate endotoxin-induced uveitis (EIU) in rats. MATERIAL AND METHODS Male Sprague-Dawley rats were divided into a normal group, a model group, a nitrogen-oxygen (N-O) group, and a hydrogen-oxygen (H-O) group. EIU was induced in rats of the latter 3 groups by injection of lipopolysaccharide (LPS). After that, rats in the N-O group inhaled a gas mixture of 67% N2 and 33% O2, while those in the H-O group inhaled a gas mixture of 67% H2 and 33% O2. All rats were graded according to the signs of uveitis after electroretinography (ERG) examination. Protein concentration in the aqueous humor (AqH) was measured. Furthermore, hematoxylin-eosin staining and immunostaining of anti-ionized calcium-binding adapter molecule 1 (Iba1) in the iris and ciliary body (ICB) were carried out. RESULTS No statistically significant differences existed in the graded score of uveitis and the b-wave peak time in the Dark-adapted 3.0 ERG among the model, N-O, and H-O groups (P>0.05), while rats of the H-O group showed a lower concentration of AqH protein than that of the model or N-O group (P0.05), while the activation of microglia cells in the H-O group was somewhat reduced (P<0.05). CONCLUSIONS Post-treatment hydrogen gas inhalation did not ameliorate the clinical signs, or reduce the infiltrating cells of EIU. However, it inhibited the elevation of protein in the AqH and reduced the microglia activation.