Breathing Hydrogen Gas Prevents Blood Vessel Damage in Mice
- Authors
- Takeshi Kiyoi, Shuang Liu, Erika Takemasa, Hirotomo Nakaoka, Naohito Hato, Masaki Mogi
- Journal
- PLoS One
- Year
- 2020
- DOI
- 10.1371/journal.pone.0227582
- Study Type
- Mouse
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- Japan
- Health Condition
- Atherosclerosis
- Body System
- Cardiovascular
TL;DR
Breathing in hydrogen gas can help reduce blood vessel damage and slow down related diseases by lowering oxidative stress in mice.
Key Finding
Mice that continuously inhaled hydrogen gas at safe environmental levels showed significantly reduced blood vessel thickening and damage after injury, with protection linked to decreased production of harmful reactive oxygen species like hydroxyl radicals.
Summary
Researchers studied whether breathing hydrogen gas could prevent blood vessel damage in mice. They exposed mice to a mixture containing 1.3% hydrogen gas for 2 weeks, then injured blood vessels in their legs to simulate disease. Mice breathing hydrogen gas showed significantly less vessel thickening and damage compared to control mice, and this protection appeared to work by reducing harmful molecules called reactive oxygen species (unstable molecules that damage cells).
Practical Takeaway
This early-stage animal study suggests hydrogen gas inhalation may help protect blood vessels from damage, but results are from mice only and cannot be directly applied to humans. Much more research, including human studies, would be needed before hydrogen gas inhalation could be recommended as a preventive strategy for vascular disease.
Abstract
Molecular hydrogen is thought to have an inhibitory effect on oxidative stress, thereby attenuating the onset and progression of various diseases including cardiovascular disease; however, few reports have assessed the preventive effect of constitutive inhalation of hydrogen gas on of vascular remodeling. Here, we investigated the effect of constitutive inhalation of hydrogen gas on vascular neointima formation using a cuff-induced vascular injury mouse model. After constitutive inhalation of compressed hydrogen gas (O2 21%, N2 77.7%, hydrogen 1.3%) or compressed air only (O2 21%, N2 79%) by C57BL/6 mice for 2 weeks from 8 weeks of age in a closed chamber, inflammatory cuff injury was induced by polyethylene cuff placement around the femoral artery under anesthesia, and hydrogen gas administration was continued until sampling of the femoral artery. Neointima formation, accompanied by an increase in cell proliferation, was significantly attenuated in the hydrogen group compared with the control group. NADPH oxidase NOX1 downregulation in response to cuff injury was shown in the hydrogen group, but the expression levels of NADPH oxidase subunits, p40phox and p47phox, did not differ significantly between the hydrogen and control groups. Although the increase in superoxide anion production did not significantly differ between the hydrogen and control groups, DNA damage was decreased as a result of reduction of reactive oxygen species such as hydroxyl radical (⋅OH) and peroxynitrite (ONOO-) in the hydrogen group. These results demonstrate that constitutive inhalation of hydrogen gas attenuates vascular remodeling partly via reduction of oxidative stress, suggesting that constitutive inhalation of hydrogen gas at a safe concentration in the living environment could be an effective strategy for prevention of vascular diseases such as atherosclerosis.