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Hydrogen sulfide (H 2 S) is an endogenous gasotransmitter with potential therapeutic value for treating a range of disorders, such as ischemia-reperfusion injury resulting from a myocardial infarction or stroke. However, the medicinal delivery of H 2 S is hindered by its corrosive and toxic nature. In addition, small molecule H 2 S donors often generate other reactive and sulfur-containing species upon H 2 S release, leading to unwanted side effects. Here, we demonstrate that H 2 S release from biocompatible porous solids, namely metal–organic frameworks (MOFs), is a promising alternative strategy for H 2 S delivery under physiologically relevant conditions. In particular, through gas adsorption measurements and density functional theory calculations we establish that H 2 S binds strongly and reversibly within the tetrahedral pockets of the fumaric acid-derived framework MOF-801 and the mesaconic acid-derived framework Zr-mes, as well as the new itaconic acid-derived framework CORN-MOF-2. These features make all three frameworks among the best materials identified to date for the capture, storage, and delivery of H 2 S. In addition, these frameworks are non-toxic to HeLa cells and capable of releasing H 2 S under aqueous conditions, as confirmed by fluorescence assays. Last, a cellular ischemia-reperfusion injury model using H9c2 rat cardiomyoblast cells corroborates that H 2 S-loaded MOF-801 is capable of mitigating hypoxia-reoxygenation injury, likely due to the release of H 2 S. Overall, our findings suggest that H 2 S-loaded MOFs represent a new family of easily-handled solid sources of H 2 S that merit further investigation as therapeutic agents. In addition, our findings add Zr-mes and CORN-MOF-2 to the growing lexicon of biocompatible MOFs suitable for drug delivery.
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A Dinuclear Persulfide‐Bridged Ruthenium Compound is a Hypoxia‐Selective Hydrogen Sulfide (H 2 S) Donor
Abstract Hydrogen sulfide (H2S) is a gaseous molecule that has received attention for its role in biological processes and therapeutic potential in diseases, such as ischemic reperfusion injury. Despite its clinical relevance, delivery of H2S to biological systems is hampered by its toxicity at high concentrations. Herein, we report the first metal‐based H2S donor that delivers this gas selectively to hypoxic cells. We further show that H2S release from this compound protects H9c2 rat cardiomyoblasts from an in vitro model of ischemic reperfusion injury. These results validate the utility of redox‐activated metal complexes as hypoxia‐selective H2S‐releasing agents for use as tools to study the role of this gaseous molecule in complex biological systems.
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- Award ID(s):
- 1750295
- PAR ID:
- 10231342
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 3
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 1588-1592
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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