Phosphoglycerate mutase 5 exacerbates cardiac ischemia-reperfusion injury through disrupting mitochondrial quality control

Hang Zhu; Ying Tan; Wenjun Du; Yang Li; Sam Toan; David Mui; Feng Tian; Hao Zhou

doi:10.1016/j.redox.2020.101777

Phosphoglycerate mutase 5 exacerbates cardiac ischemia-reperfusion injury through disrupting mitochondrial quality control

Redox Biol. 2021 Jan:38:101777. doi: 10.1016/j.redox.2020.101777. Epub 2020 Nov 1.

Authors

Hang Zhu¹, Ying Tan², Wenjun Du³, Yang Li⁴, Sam Toan⁴, David Mui⁵, Feng Tian⁶, Hao Zhou⁷

Affiliations

¹ Department of Cardiology, Chinese PLA General Hospital, Beijing, 100853, China.
² Department of Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
³ Medical School of Chinese PLA, Chinese PLA General Hospital, Beijing, 100853, China.
⁴ Department of Chemical Engineering, University of Minnesota-Duluth, Duluth, MN, 55812, USA.
⁵ Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
⁶ Department of Cardiology, Chinese PLA General Hospital, Beijing, 100853, China. Electronic address: tianfeng@126.com.
⁷ Department of Cardiology, Chinese PLA General Hospital, Beijing, 100853, China. Electronic address: zhouhao301@outlook.com.

Abstract

The death of cardiomyocytes either through apoptosis or necroptosis is the pathological feature of cardiac ischemia-reperfusion (I/R) injury. Phosphoglycerate mutase 5 (PGAM5), a mitochondrially-localized serine/threonine-protein phosphatase, functions as a novel inducer of necroptosis. However, intense debate exists regarding the effect of PGAM5 on I/R-related cardiomyocyte death. Using cardiac-specific PGAM5 knockout (PGAM5^CKO) mice, we comprehensively investigated the precise contribution and molecular mechanism of PGAM5 in cardiomyocyte death. Our data showed that both PGAM5 transcription and expression were upregulated in reperfused myocardium. Genetic ablation of PGAM5 suppressed I/R-mediated necroptosis but failed to prevent apoptosis activation, a result that went along with improved heart function and decreased inflammation response. Regardless of PGAM5 status, mitophagy-related cell death was not apparent following I/R. Under physiological conditions, PGAM5 overexpression in primary cardiomyocytes was sufficient to induce cardiomyocyte necroptosis rather than apoptosis. At the sub-cellular levels, PGAM5 deficiency increased mitochondrial DNA copy number and transcript levels, normalized mitochondrial respiration, repressed mitochondrial ROS production, and prevented abnormal mPTP opening upon I/R. Molecular investigation demonstrated that PGAM5 deletion interrupted I/R-mediated Drp^S637 dephosphorylation but failed to abolish I/R-induce Drp1^S616 phosphorylation, resulting in partial inhibition of mitochondrial fission. In addition, declining Mfn2 and OPA1 levels were restored in PGAM5^CKO cardiomyocytes following I/R. Nevertheless, PGAM5 depletion did not rescue suppressed mitophagy upon I/R injury. In conclusion, our results provide an insight into the specific role and working mechanism of PGAM5 in driving cardiomyocyte necroptosis through imposing mitochondrial quality control in cardiac I/R injury.

Keywords: Cardiac I/R injury; Death; Mitochondrial fission; Mitochondrial quality control; Mitophagy; Necroptosis; PGAM5.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Heart / physiopathology*
Mice
Mice, Knockout
Mitochondria
Mitochondrial Dynamics*
Mitophagy
Phosphoprotein Phosphatases / genetics*
Reperfusion Injury*

Substances

PGAM5 protein, mouse
Phosphoprotein Phosphatases