Hydrogen Gas Protects Brain from Stroke Damage in Mouse Study

Authors
Journal
Medical Gas Research
Year
DOI
10.4103/2045-9912.229596
Study Type
Mouse
Outcome
Positive
Peer Reviewed
Yes
Country
China
Health Condition
Ischemic Stroke
Body System
Nervous System

TL;DR

Breathing in a high concentration of hydrogen gas helps to reduce brain damage and improve recovery in mice after a stroke, but it does not affect a specific cell death pathway known as necroptosis.

Key Finding

Hydrogen inhalation significantly reduced brain damage, decreased brain swelling, and improved neurological function in mice after stroke-like injury, but this protection did not involve blocking a cell death process called necroptosis.

Summary

Researchers gave mice a mixture of hydrogen and oxygen to breathe after inducing a stroke-like injury (blocking blood flow to the brain and then restoring it). Mice that inhaled hydrogen had smaller brain damage areas, less brain swelling, and better neurological function compared to control mice. Surprisingly, the protective effect did not work through a mechanism called necroptosis (a type of cell death), suggesting hydrogen protects the brain through a different biological pathway.

Practical Takeaway

This mouse study suggests hydrogen gas may have neuroprotective effects after stroke through a previously unknown mechanism. However, this is early-stage animal research, and it remains unclear whether these results would apply to humans or what the optimal hydrogen dose and delivery method would be for clinical use.

Abstract

This study aimed to investigate the role of necroptosis in the neuroprotection of hydrogen in a mouse model of cerebral ischemia/reperfusion (I/R) injury. C57BL mice were randomly divided into sham group, I/R group, hydrogen/oxygen group (HO), nitrogen/oxygen group (NO). Middle cerebral artery occlusion (MCAO) for 1 hour followed by reperfusion was introduced to animals which were allowed to inhale 66.7% hydrogen/33.3% oxygen for 90 minutes since the beginning of reperfusion. Mice in NO group inhaled 66.7% nitrogen/33.3% oxygen. 24 hours after MCAO, brain infarction, brain water content and neurological function were evaluated. The protein expression of mixed lineage kinase domain like protein (MLKL) was detected at 3, 6, 12, 24 and 72 hours after reperfusion in HO group and the protein and mRNA expression of MLKL at 24 hours after MCAO in four groups. Hydrogen inhalation significantly reduced infarct volume, attenuated brain edema and improved neurobehavioral deficit in MCAO mice. The MLKL expression increased after MCAO and peaked at 6-24 hours after reperfusion. However, hydrogen inhalation had no significant effect on the MLKL expression at transcriptional and translational levels after MCAO. This study indicates high concentration hydrogen improves mouse neurological outcome after cerebral I/R injury independent of anti-necroptosis. © 2018 Medical Gas Research Published by Wolters Kluwer-Medknow.