Hydrogen-Releasing Bacteria Gel Injected Into the Heart Repairs Damage After Heart Attack

Authors
Journal
Nature Biomedical Engineering
Year
DOI
10.1038/s41551-026-01700-z
Study Type
Pig
Outcome
Positive
Peer Reviewed
Yes
Country
China
Health Condition
Myocardial Ischemia-Reperfusion Injury
Body System
Cardiovascular

TL;DR

An injectable hydrogel containing hydrogen-producing photosynthetic bacteria reduced heart ischemia-reperfusion injury in a porcine model.

Key Finding

An injectable gel containing hydrogen-producing bacteria reduced heart damage from ischemia-reperfusion injury in rodent and pig models by sustaining hydrogen production and protecting mitochondrial function.

Summary

Researchers developed an injectable gel containing hydrogen-producing bacteria that could be injected into heart tissue damaged by lack of blood flow followed by blood flow restoration (a condition called ischemia-reperfusion injury). When exposed to light, the bacteria produced hydrogen gas, which reduced harmful oxygen molecules and protected the heart's energy-producing structures (mitochondria). The treatment reduced heart damage in both rodents and pigs.

Practical Takeaway

This is early-stage research in animal models only, with no human testing yet. While the results suggest a novel approach to delivering hydrogen therapy for heart injury, it remains unclear whether this bacterial gel method would be safe or effective in humans, and it requires light exposure to work—a significant practical limitation for clinical use.

Abstract

Cardioprotective effects of current therapies for mitigating ischaemia/reperfusion (I/R) injury have had limited success. The major challenge is to effectively control oxidative stress while preserving mitochondrial function in a timely manner. Hydrogen (H2) selectively reduces cytotoxic oxygen radicals, aiding in the regulation of physiological and pathological functions. However, the efficacy of H2 therapy is highly dependent on the amount and rate of H2 release, making it critically important to develop rapid, simple and efficient techniques for evolving therapeutic H2. Here we encapsulate H2-producing photosynthetic bacteria (PSB) in an injectable porcine dermal extracellular matrix (ECM) hydrogel to facilitate cardiac I/R injury repair. Upon light exposure, sustained and high H2 production from PSB hydrogel preserves mitochondrial homeostasis and essential functions. In a porcine model of cardiac I/R injury, PSB hydrogel treatment effectively mitigates myocardial damage and salvages jeopardized myocardium. We anticipate that this bacterial therapy for photosynthetic H2 production could provide an improved treatment for I/R-related diseases.