MiR-181c protects cardiomyocyte injury by preventing cell apoptosis through PI3K/Akt signaling pathway

Area of Science:

• Cardiology
• Molecular Biology
• Biochemistry

Background:

• Cardiomyocyte apoptosis is a key factor in heart failure development and associated mortality.
• Doxorubicin (DOX) and hypoxia/reoxygenation (H/R) are common inducers of cardiomyocyte injury and apoptosis.
• Understanding the regulatory mechanisms of apoptosis is crucial for treating cardiovascular diseases.

Purpose of the Study:

• To investigate the role of microRNA-181c (miR-181c) in regulating myocardial apoptosis.
• To determine the effect of miR-181c on cardiomyocyte injury induced by DOX or H/R.
• To elucidate the molecular pathway involved in miR-181c-mediated cardioprotection.

Main Methods:

• Establishment of a doxorubicin-induced heart failure mouse model.
• Induction of apoptosis in H9c2 cardiomyocytes using hypoxia/reoxygenation (H/R) or doxorubicin (DOX).
• Quantification of apoptosis using TUNEL assay and flow cytometry (Annexin V-PI staining).
• Assessment of miR-181c expression and its effect on target proteins (Fas, IL-6, TNF-α, Bcl2, p-Akt) via RT-PCR and Western blot analysis.

Main Results:

• miR-181c expression was significantly suppressed in DOX-induced heart failure.
• Overexpression of miR-181c reduced cardiomyocyte apoptosis in both animal models and in vitro cell cultures.
• miR-181c downregulated pro-apoptotic factors (Fas, IL-6, TNF-α) and upregulated anti-apoptotic factors (Bcl2) and Akt phosphorylation.
• These effects were mediated through the PI3K/Akt signaling pathway.

Conclusions:

• miR-181c exhibits a protective effect against heart failure by inhibiting cardiomyocyte apoptosis.
• The PI3K/Akt pathway is a key mediator of miR-181c's cardioprotective function.
• miR-181c represents a potential therapeutic target for managing cardiovascular disease exacerbation.