SPI1 Regulates Autophagy by Promoting ATG7 Transcription to Enhance Ferroptosis in Myocardial Ischemia/Reperfusion

Wu-Lin Li1,2, Xiao Han2,3, Wei-Long Pan1

  • 1Department of Emergency and Critical Care Medicine, Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Sciences, Shanghai, China.

PubMed

Insights

Myocardial ischemia/reperfusion injury (MIRI) involves autophagy-dependent ferroptosis. Targeting SPI1 to inhibit ATG7 transcription alleviates MIRI by suppressing ferroptosis and autophagy.

Area of Science:

  • Cardiovascular Research
  • Cellular Biology
  • Molecular Medicine

Background:

  • Myocardial ischemia/reperfusion injury (MIRI) is a significant complication of coronary artery disease (CAD).
  • Autophagy-dependent ferroptosis is a key mechanism in MIRI, but its regulation is not fully understood.
  • Targeting this pathway offers a potential therapeutic strategy for MIRI.

Purpose of the Study:

  • To investigate the precise mechanisms of autophagy-dependent ferroptosis in MIRI.
  • To identify key regulatory factors involved in this process.
  • To explore the therapeutic potential of targeting these regulators.

Main Methods:

  • Murine model of myocardial ischemia/reperfusion (I/R) and hypoxia/reoxygenation (H/R) in cardiac myocytes.
  • Biochemical assays (CK, LDH, ROS, MDA, Fe2+, GSH), cell viability (CCK-8), and tissue staining (Evans blue/TTC, HE, TUNEL).
  • Molecular analyses including ChIP, immunohistochemistry, immunofluorescence, qRT-PCR, and western blot to assess autophagy and ferroptosis markers (ATG7, SPI1).

Main Results:

  • Autophagy-dependent ferroptosis was confirmed in MIRI models, with elevated ATG7 expression.
  • Knockdown of ATG7 alleviated MIRI and inhibited ferroptosis and autophagy.
  • SPI1 was identified as a key regulator that binds to the ATG7 promoter, enhancing its transcription during myocardial I/R.

Conclusions:

  • SPI1 promotes ATG7 transcription, exacerbating ferroptosis and autophagy in MIRI.
  • SPI1 knockdown mitigates MIRI by suppressing ferroptosis and autophagy.
  • Targeting SPI1 and its downstream effects on ATG7 presents a promising therapeutic avenue for MIRI and related cardiovascular diseases.

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