Hydrogen Gas Protects Lungs During Transplant Surgery in Rats
- Authors
- Jiahang Zhang, Huacheng Zhou, Jinfeng Liu, Chao Meng, Lin Deng, Wenzhi Li
- Journal
- Microvascular Research
- Year
- 2019
- DOI
- 10.1016/j.mvr.2019.103885
- Study Type
- Rat
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- China
- Health Condition
- Ischemia-Reperfusion Injury
- Body System
- Respiratory
TL;DR
Breathing in hydrogen gas helps protect rat lungs from damage after the heart has stopped beating, potentially improving the success of lung transplants.
Key Finding
Lungs treated with 3% hydrogen gas during the warm ischemia phase (the period after cardiac death but before transplant) showed significantly better function, less inflammation, and reduced cell damage compared to untreated lungs in this rat model.
Summary
This rat study tested whether breathing hydrogen gas could protect donor lungs from damage during the time between cardiac death and transplantation. Researchers gave one group of rats hydrogen gas to breathe during this critical period, while a control group breathed regular air. After transplanting the lungs into recipient rats, the hydrogen-treated lungs showed better function, less fluid buildup, less inflammation, and less cell damage compared to control lungs.
Practical Takeaway
This is early-stage research in rats only, so it cannot yet be applied to human lung transplants. The results suggest hydrogen gas inhalation may help protect donor lungs during the critical period after cardiac death, but human clinical trials would be needed to determine if this approach is safe and effective in actual transplant patients.
Abstract
Background: Successful amelioration of long-term warm ischemia lung injury in donors after cardiac death (DCDs) can remarkably improve outcomes. Hydrogen gas provides potent anti-inflammatory and antioxidant effects against ischemia-reperfusion injury (IRI). This study observed the effects of hydrogen inhalation on lung grafts during the warm ischemia phase in cardiac death donors. Methods: After cardiac death, rat donor lungs (n = 8) underwent mechanical ventilation with 40% oxygen plus 60% nitrogen (control group) or 3% hydrogen and 40% oxygen plus 57% nitrogen (hydrogen group) for 2 h during the warm ischemia phase in situ. Then, lung transplantation was performed after 2 h of cold storage and 3 h of recipient reperfusion prior to lung graft assessment. Rats that underwent left thoracotomy without transplantation served as the sham group (n = 8). The results of static compliance and arterial blood gas analysis were assessed in the recipients. The wet-to-dry weight ratio (W/D), inflammation, oxidative stress, cell apoptosis and histologic changes were evaluated after 3 h of reperfusion. Nuclear factor kappa B (NF-κB) protein expression in the graft was analyzed by Western blotting. Results: Compared with the sham group, lung function, W/D, inflammatory reaction, oxidative stress and histological changes were decreased in both transplant groups (control and hydrogen groups). However, compared with the control group, exposure to 3% hydrogen significantly improved lung graft static compliance and oxygenation and remarkably decreased the wet-to-dry weight ratio, inflammatory reactions, and lipid peroxidation. Furthermore, hydrogen improved the lung graft histological changes, decreased the lung injury score and apoptotic index and reduced NF-κB nuclear accumulation in the lung grafts. Conclusion: Lung inhalation with 3% hydrogen during the warm ischemia phase attenuated lung graft IRI via NF-κB-dependent anti-inflammatory and antioxidative effects in rat donors after cardiac death.