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Oxidation of protein kinase a regulatory subunit PKARIα protects against myocardial ischemia-reperfusion injury by inhibiting lysosomal-triggered calcium release

Oxidation of protein kinase a regulatory subunit PKARIα protects against myocardial ischemia-reperfusion injury by inhibiting lysosomal-triggered calcium release

Authors :
Gerard A Marchal
Keith M. Channon
Oliver Lomas
Raja Jayaram
Besarte Vrellaku
Parag R Gajendragadkar
Nadiia Rawlings
Barbara Casadei
Pawel Swietach
Jillian N. Simon
Larissa Fabritz
Philip Eaton
Dominic Waithe
Sandy Chu
Rana Sayeed
Stefania Monterisi
Fahima Syeda
Manuela Zaccolo
Source :
Circulation
Publication Year :
2020
Publisher :
Lippincott, Williams & Wilkins, 2020.

Abstract

Supplemental Digital Content is available in the text.<br />Background: Kinase oxidation is a critical signaling mechanism through which changes in the intracellular redox state alter cardiac function. In the myocardium, PKARIα (type-1 protein kinase A) can be reversibly oxidized, forming interprotein disulfide bonds in the holoenzyme complex. However, the effect of PKARIα disulfide formation on downstream signaling in the heart, particularly under states of oxidative stress such as ischemia and reperfusion (I/R), remains unexplored. Methods: Atrial tissue obtained from patients before and after cardiopulmonary bypass and reperfusion and left ventricular (LV) tissue from mice subjected to I/R or sham surgery were used to assess PKARIα disulfide formation by immunoblot. To determine the effect of disulfide formation on PKARIα catalytic activity and subcellular localization, live-cell fluorescence imaging and stimulated emission depletion super-resolution microscopy were performed in prkar1 knock-out mouse embryonic fibroblasts, neonatal myocytes, or adult LV myocytes isolated from “redox dead” (Cys17Ser) PKARIα knock-in mice and their wild-type littermates. Comparison of intracellular calcium dynamics between genotypes was assessed in fura2-loaded LV myocytes, whereas I/R-injury was assessed ex vivo. Results: In both humans and mice, myocardial PKARIα disulfide formation was found to be significantly increased (2-fold in humans, P=0.023; 2.4-fold in mice, P

Details

Language :
English
Database :
OpenAIRE
Journal :
Circulation
Accession number :
edsair.doi.dedup.....4f7540b3bf718697aae0ed5bff330e19
Full Text :
https://doi.org/10.1161/circulationaha.120.046761