Cardiac ischemia/reperfusion stress reduces inner mitochondrial membrane protein (mitofilin) levels during early reperfusion

Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved..

Mitochondrial inner membrane protein (Mitofilin or Mic60) is a mitochondria-shaping protein that plays a key role in maintaining mitochondrial cristae structure and remodeling. We recently showed that Mitofilin knockdown in H9c2 myoblasts induces mitochondrial structural damage resulting in mitochondrial dysfunction that is responsible for cell death via apoptosis. Here, we investigated the role of Mitofilin regulation in ischemia/reperfusion (I/R) injury and studied the relationship between Mitofilin and Cyclophilin (CypD), a key regulator of mitochondrial permeability transition pore (mPTP) opening. C57Bl6 male mice hearts were subjected to different ischemia times (15, 30, or 45 min) followed by a 2 h reperfusion period, or 45 min ischemia followed by 0, 15, 30, 60, or 120 min reperfusion to determine the impact of ischemia or reperfusion times on Mitofilin levels and its interaction with CypD. We found that the increase in myocardial infarct size and the reduction of mitochondrial calcium retention capacity were concomitant with Mitofilin reduction as a function of ischemic duration. We also found that 15 min reperfusion after 45 min ischemia was sufficient to cause a reduction of Mitofilin levels compared to sham, while 45 min ischemia alone was not enough to cause a significant decrease of Mitofilin. We revealed that the c-terminus coiled-coiled domain of Mitofilin is important for its interaction with CypD and the deletion of this identified sequence resulted in a loss of Mitofilin-CypD link, dissipation of mitochondrial membrane potential and increase in cell death. A decrease of the levels of Mitofilin was also associated with mitochondrial structural integrity damage, increased reactive oxygen species (ROS) production, and calpain activity. Our results indicate that Mitofilin physically binds to CypD in the inner mitochondrial membrane and the disruption of this interaction may play a critical role in the increase of mitochondrial dysfunction and initiation of myocytes' death after I/R injury.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:158

Enthalten in:

Free radical biology & medicine - 158(2020) vom: 15. Okt., Seite 181-194

Sprache:

Englisch

Beteiligte Personen:

Tombo, Nathalie [VerfasserIn]
Imam Aliagan, Abdulhafiz D [VerfasserIn]
Feng, Yansheng [VerfasserIn]
Singh, Harpreet [VerfasserIn]
Bopassa, Jean C [VerfasserIn]

Links:

Volltext

Themen:

And mitochondrial structural integrity and function
Cyclophilin D
Inner mitochondrial membrane (immt, mitofilin)
Ischemia/reperfusion injury
Journal Article
Membrane Proteins
Mitochondrial Membrane Transport Proteins
Mitochondrial dysfunction
Mitochondrial permeability transition pore (mPTP)
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 18.06.2021

Date Revised 29.01.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.freeradbiomed.2020.06.039

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM31302314X