BENEFICIAL EFFECTS OF HYDROGEN IN THE CNS AND A NEW BRAIN-STOMACH INTERACTION

Abstract

A new medical gas, molecular hydrogen (H2), has been reported to be effective for a variety of disorders and clinical trials have shown promising results. Though the precise mechanism is still unknown, it is obvious that H2 has multiple effects. The first prominent effect of H2 was as antioxidant or reactive oxygen species (ROS)-scavenger, though it blocks only hydroxyl radicals (•OH), which are the most toxic ROS, but not others. Then the possibility as a signal modulator was proposed and it became obvious that many protective effects of H2 were not simply explained by antioxidant. Blocking reactive oxygen species (ROS) would be a rather direct anti-oxidative effect and if so, H2 need to encounter ROS. However, long-term consumption of H2 makes some unknown biological change which subsequently reveals resistance to ROS without any presence of H2 itself. One of the ROS-resistant mechanisms of H2 is due to brain-stomach interaction via ghrelin. The action of H2 in the stomach seems to be quite specific; it activates β1 but not β2 adrenoceptor to increase the production and the release of ghrelin. Whether ghrelin secretion is a universal mechanism in all other protective effects induced by drinking H2 water needs to be elucidated.

Study details

Article type

Review

Disease / injury model

MPTP-induced Parkinson’s disease model, Type I allergy, LPS-induced inflammation, traumatic brain injury, anti-type II collagen antibody-induced arthritis, amyloid-β-induced Alzheimer’s disease

Duration

7 days

Dose comparison

No explicit dose/concentration comparison; only one concentration of H2 water was used in the main animal studies.

Dose-dependent effect

No

Outcome

Positive

Findings

Molecular hydrogen (H2) shows protective effects in various diseases, especially neurodegenerative diseases, through multiple mechanisms including antioxidant activity and modulation of signaling pathways. Notably, drinking H2 water induces neuroprotective effects in Parkinson’s disease models via a brain-stomach interaction involving β1-adrenergic receptor-mediated ghrelin release. The effect is blocked by β1-adrenergic antagonists and ghrelin receptor inhibitors, indicating a specific signaling cascade. H2 water also modulates inflammatory and oxidative stress markers in various models.