Hydrogen Gas Inhalation Improves Survival in Heat Stroke
- Authors
- Sang Kien Truong, Takasumi Katoh, Soichiro Mimuro, Tsunehisa Sato, Kensuke Kobayashi, Yoshiki Nakajima
- Journal
- Shock
- Year
- 2021
- DOI
- 10.1097/SHK.0000000000001797
- Study Type
- Rat
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- Japan
- Health Condition
- Heat Stroke
- Body System
- Cardiovascular
TL;DR
Breathing in 2% hydrogen gas helped rats survive heat stroke better and protected their blood vessel linings.
Key Finding
Inhaling 2% hydrogen gas significantly improved survival rates in heat-stroked rats and reduced damage to the protective lining of blood vessels.
Summary
This study tested whether inhaling hydrogen gas could help rats survive heat stroke and protect their blood vessels. Researchers exposed rats to extreme heat and had them breathe air containing either no hydrogen, 2%, or 4% hydrogen gas. The rats that breathed 2% hydrogen had better survival rates and showed less damage to a protective layer inside their blood vessels called the endothelial glycocalyx. The hydrogen appeared to work by reducing harmful molecules (oxidative stress) and calming inflammatory responses in the body.
Practical Takeaway
This is an early-stage animal study showing potential benefits of hydrogen inhalation for heat stroke, but it was conducted only in rats and does not yet indicate whether the same effects would occur in humans. More research, including human trials, would be needed before hydrogen therapy could be considered a viable treatment for heat stroke in people.
Abstract
Heat stroke is characterized by excessive oxidative stress and inflammatory responses, both of which are implicated in vascular endothelial glycocalyx shedding and heat-stroke mortality. Although molecular hydrogen has antioxidation and anti-inflammatory potency, its effect on the vascular endothelial glycocalyx in heat stroke has not been examined. Therefore, the aim of this study was to investigate the influence of hydrogen inhalation on the survival and thickness of the vascular endothelial glycocalyx of rats subjected to heat stroke. Altogether, 98 Wistar rats were assigned to the experiments. A heat-controlled chamber set at 40°C temperature and 60% humidity was used to induce heat stroke. After preparation, the anesthetized rats that underwent the heating process were subjected to an hour of stabilization in which 0%, 2%, or 4% hydrogen gas was inhaled and maintained until the experiment ended. In addition to survival rate assessments, blood samples and left ventricles were collected to evaluate the thickness of the vascular endothelial glycocalyx and relevant biomarkers. The results showed that 2% hydrogen gas significantly improved survival in the heat-stroked rats and partially preserved the thickness of the endothelial glycocalyx. In addition, serum levels of endotoxin, syndecan-1, malondialdehyde, and tumor necrosis factor-α decreased, whereas superoxide dismutase levels increased, indicating that inhalation of 2% hydrogen attenuated the damage to the vascular endothelial glycocalyx through its antioxidative and anti-inflammatory effects.