Oral Intake of Hydrogen Water Improves Retinal Blood Flow Dysregulation in Response to Flicker Stimulation and Systemic Hyperoxia in Diabetic Mice.

PURPOSE: To examine the effects of hydrogen water on retinal blood flow (RBF) dysregulation in diabetes, we evaluated changes in RBF in response to flicker stimulation and systemic hyperoxia in diabetic mice.

METHODS

Twelve type 2 diabetic mice were divided into a group that received non-hydrogen water (n = 6, control group) and the other that received hydrogen-rich water (0.6-0.8 mM) (n = 6, HRW group) from six weeks of age. Body weight, blood glucose, intraocular pressure, and blood pressure were evaluated from eight to 14 weeks of age. RBF was measured in the vascular area of the optic disc as mean blur rate using laser speckle flowgraphy in the resting state and response to flicker stimulation and hyperoxia. We evaluated glial activation and oxidative stress based on immunofluorescence expression.

RESULTS

At 14 weeks, blood glucose level was significantly lower in the HRW group, though still elevated. RBF changes improved significantly in the HRW group compared with the control group from eight weeks of age and persisted throughout the study. Immunofluorescent expression of glial fibrillary acidic protein, particularly in the outer plexiform layer, was significantly decreased in the HRW group. Among oxidative stress markers, 3-nitrotyrosine was significantly suppressed in the HRW group.

CONCLUSIONS

Hydrogen-rich water intake significantly improved RBF dysregulation in diabetic mice. Hydrogen may improve impaired neurovascular coupling function in diabetic mice by suppressing gliosis and oxidative stress in the retina.

TRANSLATIONAL RELEVANCE: This study highlights the potential of oral intake of hydrogen-rich water to mitigate retinal dysfunction in diabetic mice.