Hydrogen Water Shows Limited Benefits for Eye Inflammation in Rats

Authors
Journal
Medical Gas Research
Year
DOI
10.4103/2045-9912.202905
Study Type
Rat
Outcome
Neutral
Peer Reviewed
Yes
Country
China
Health Condition
Uveitis
Body System
Ocular

TL;DR

Hydrogen-rich saline (HRS) was not very effective in reducing eye inflammation in rats, unlike dexamethasone, a standard anti-inflammatory drug.

Key Finding

Hydrogen-rich saline failed to significantly reduce clinical signs of inflammation or restore retinal function in rats with endotoxin-induced uveitis, though it showed modest effects in reducing protein accumulation in eye fluid during mild inflammation.

Summary

Researchers tested whether hydrogen-rich saline (a salt solution containing dissolved hydrogen) could reduce inflammation in rats with endotoxin-induced uveitis (eye inflammation caused by bacterial toxins). The treatment was compared to dexamethasone, a standard anti-inflammatory drug. While hydrogen-rich saline did not reduce visible signs of eye inflammation or restore retinal function as effectively as dexamethasone, it did show some ability to limit protein buildup in the eye's fluid, particularly in mild cases of inflammation.

Practical Takeaway

This rat study suggests hydrogen-rich saline has limited effectiveness as a treatment for uveitis compared to established medications like dexamethasone. While the compound showed some activity in reducing specific inflammatory markers in mild cases, the overall lack of clinical benefit in this animal model indicates more research is needed before considering it for eye inflammation. Results from animal studies do not always translate to humans.

Abstract

The therapeutic effects of hydrogen-rich saline (HRS) have been reported for a wide range of diseases mainly via selectively reducing the amount of reactive oxygen species. Oxidative stress plays an important role in the pathogenesis of uveitis and endotoxin-induced uveitis (EIU). In this study, we investigated whether HRS can mitigate EIU in rats. Sprague-Dawley rats were randomly divided into Norm group, Model group, HRS group, dexamethasone (DEX) group, and rats in the latter three groups were injected with equal amount of lipopolysaccharide (LPS) to induce EIU of different severities (by 1 mg/kg of LPS, or 1/8 mg/kg of LPS). Rats in HRS group were injected with HRS intraperitoneally at three different modes to purse an ameliorating effect of EIU (10 mL/kg of HRS immediately after injection of 1 mg/kg of LPS, 20 mL/kg of HRS once a day for 1 week before injection of 1 mg/kg of LPS and at 0, 0.5, 1, 2, 6, 8, 12 hours after LPS administration, or 20 mL/kg of HRS once a day for 1 week before injection of 1/8 mg/kg of LPS, and at 0, 0.5, 1, 2, 6, 8, 12, 24 hours and once a day for 3 weeks after LPS administration). Rats of DEX group were injected with 1 mL/kg of DEX solution intraperitoneally immediately after LPS administration. Rats in Norm and Model groups did not receive any treatment. All rats were examined under slit lamp microscope and graded according to the clinical signs of uveitis. Electroretinogram, quantitative analysis of protein in aqueous humor (AqH) and histological examination of iris and ciliary body were also carried out. Our results showed that HRS did not obviously ameliorate the signs of uveitis under slit lamp examination and the inflammatory cells infiltration around iris and cilliary body of EIU induced by 1 mg/kg or 1/8 mg/kg of LPS (P > 0.05), while DEX significantly reduced the inflammation reflected by the above two indicators (P 0.05), while DEX had an obvious therapeutic effect (P < 0.05). However, HRS exerted an inhibition trend on elevation of protein in AqH of EIU induced by 1 mg/kg of LPS, and significantly reduced the increasing amount of protein in AqH of mild EIU induced by 1/8 mg/kg of LPS (P < 0.05). In conclusion, HRS could not obviously mitigate EIU in rats, while it could inhibit the elevation of AqH protein.