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Abstract Gaseous signaling molecules such as nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S) have recently been recognized as essential signal mediators that regulate diverse physiological and pathological processes in the human body. With the evolution of gaseous signaling molecule biology, their therapeutic applications have attracted growing attention. One of the challenges in translational research of gaseous signaling molecules is the lack of efficient and safe delivery systems. To tackle this issue, researchers developed a library of gas donors, which are low molecular weight compounds that can release gaseous signaling molecules upon decomposition under physiological conditions. Despite the significant efforts to control gaseous signaling molecule release from gas donors, the therapeutic potential of gaseous signaling molecules cannot be fully explored due to their unfavorable pharmacokinetics and toxic side effects. Recently, the use of nanoparticle‐based gas donors, especially self‐assembled polymeric gas donors, have emerged as a promising approach. In this review, we describe the development of conventional small gas donors and the challenges in their therapeutic applications. We then illustrate the concepts and critical aspects for designing self‐assembled polymeric gas donors and discuss the advantages of this approach in gasotransmistter delivery. We also highlight recent efforts to develop the delivery systems for those molecules based on self‐assembled polymeric nanostructures. This article is categorized under:Therapeutic Approaches and Drug Discovery > Emerging Technologies
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Electrochemical Modulation of Carbon Monoxide‐Mediated Cell Signaling
Abstract Despite the critical role played by carbon monoxide (CO) in physiological and pathological signaling events, current approaches to deliver this messenger molecule are often accompanied by off‐target effects and offer limited control over release kinetics. To address these challenges, we develop an electrochemical approach that affords on‐demand release of CO through reduction of carbon dioxide (CO2) dissolved in the extracellular space. Electrocatalytic generation of CO by cobalt phthalocyanine molecular catalysts modulates signaling pathways mediated by a CO receptor soluble guanylyl cyclase. Furthermore, by tuning the applied voltage during electrocatalysis, we explore the effect of the CO release kinetics on CO‐dependent neuronal signaling. Finally, we integrate components of our electrochemical platform into microscale fibers to produce CO in a spatially‐restricted manner and to activate signaling cascades in the targeted cells. By offering on‐demand local synthesis of CO, our approach may facilitate the studies of physiological processes affected by this gaseous molecular messenger.
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- Award ID(s):
- 2204757
- PAR ID:
- 10286217
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 37
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 20325-20330
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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