Cardioprotection of ischemic preconditioning in rats involves upregulating adiponectin

Area of Science:

• Cardiovascular Research
• Molecular Cardiology
• Cellular Signaling

Background:

• Ischemic preconditioning (IPC) and adiponectin (APN) are known cardioprotective agents.
• The precise mechanism by which IPC exerts its protective effects, particularly the role of APN, remains unclear.

Purpose of the Study:

• To investigate if IPC enhances myocardial protection by upregulating APN expression.
• To elucidate the role of APN in mediating the cardioprotective effects of IPC.

Main Methods:

• Male adult rats underwent IPC followed by myocardial infarction (MI).
• Cardiac APN and receptor knockdowns were induced using small-interfering RNA.
• Globular APN (gAd) was administered, and cardiac function, infarct size, APN levels, and AMPK phosphorylation were assessed.

Main Results:

• IPC significantly improved cardiac function and reduced infarct size in rats.
• APN and its receptors were upregulated post-IPC.
• The protective effects of IPC were diminished in APN-knockdown rats and restored by gAd treatment.
• IPC-induced cardioprotection involved the activation of the AMP-activated protein kinase (AMPK) pathway.

Conclusions:

• Cardioprotective effects of IPC are partly mediated by the upregulation of adiponectin.
• Adiponectin plays a crucial role in IPC-induced myocardial protection through the AMPK signaling pathway.