Logo image
A neuroglobin-based high-affinity ligand trap reverses carbon monoxide–induced mitochondrial poisoning
Journal article   Open access   Peer reviewed

A neuroglobin-based high-affinity ligand trap reverses carbon monoxide–induced mitochondrial poisoning

Jason J. Rose, Kaitlin A. Bocian, Qinzi Xu, Ling Wang, Anthony W. DeMartino, Xiukai Chen, Catherine G. Corey, Danielle A. Guimarães, Ivan Azarov, Xueyin N. Huang, …
The Journal of biological chemistry, Vol.295(19), pp.6357-6371
05/08/2020
DOI: 10.1074/jbc.RA119.010593
PMCID: PMC7212636
PMID: 32205448
url
https://doi.org/10.1074/jbc.RA119.010593View
Published (Version of record) Open Access

Abstract

Carbon monoxide (CO) remains the most common cause of human poisoning. The consequences of CO poisoning include cardiac dysfunction, brain injury, and death. CO causes toxicity by binding to hemoglobin and by inhibiting mitochondrial cytochrome c oxidase (CcO), thereby decreasing oxygen delivery and inhibiting oxidative phosphorylation. We have recently developed a CO antidote based on human neuroglobin (Ngb-H64Q-CCC). This molecule enhances clearance of CO from red blood cells in vitro and in vivo. Herein, we tested whether Ngb-H64Q-CCC can also scavenge CO from CcO and attenuate CO-induced inhibition of mitochondrial respiration. Heart tissue from mice exposed to 3% CO exhibited a 42 ± 19% reduction in tissue respiration rate and a 33 ± 38% reduction in CcO activity compared with unexposed mice. Intravenous infusion of Ngb-H64Q-CCC restored respiration rates to that of control mice correlating with higher electron transport chain CcO activity in Ngb-H64Q-CCC–treated compared with PBS-treated, CO-poisoned mice. Further, using a Clark-type oxygen electrode, we measured isolated rat liver mitochondrial respiration in the presence and absence of saturating solutions of CO (160 μm) and nitric oxide (100 μm). Both CO and NO inhibited respiration, and treatment with Ngb-H64Q-CCC (100 and 50 μm, respectively) significantly reversed this inhibition. These results suggest that Ngb-H64Q-CCC mitigates CO toxicity by scavenging CO from carboxyhemoglobin, improving systemic oxygen delivery and reversing the inhibitory effects of CO on mitochondria. We conclude that Ngb-H64Q-CCC or other CO scavengers demonstrate potential as antidotes that reverse the clinical and molecular effects of CO poisoning.
antidotes carbon monoxide CO poisoning hemoglobin hypoxia hypoxia-inducible factor (HIF) medical toxicology mitochondria mitochondrial disease mitochondrial respiratory chain complex neuroglobin nitric oxide

Details

Logo image