CircRNA Larp4b/miR-298-5p/Mef2c Regulates Cardiac Hypertrophy Induced by Angiotensin II

Area of Science:

• Cardiovascular Biology
• Molecular Biology
• Genetics

Background:

• Cardiac hypertrophy (CH) is a key indicator of heart failure progression.
• Circular RNAs (circRNAs) are implicated in various human diseases.
• The specific role of circ_Larp4b in myocardial hypertrophy remains uninvestigated.

Purpose of the Study:

• To investigate the function of circ_Larp4b in Angiotensin II-induced cardiac hypertrophy.
• To elucidate the molecular mechanism involving circ_Larp4b, microRNA-298-5p, and myocyte enhancer factor 2 (Mef2c) in CH.

Main Methods:

• Established a cell model of CH using Angiotensin II (Ang II) treatment in HL-1 cells.
• Quantified gene expression of circ_Larp4b, miR-298-5p, and Mef2c using qRT-PCR.
• Assessed protein levels of CH markers (ACTN2, β-MHC, ANP) and Mef2c via Western blot.
• Validated molecular interactions using dual-luciferase reporter and RNA pull-down assays.

Main Results:

• Circ_Larp4b and Mef2c expression were elevated in Ang II-treated HL-1 cells.
• Downregulation of circ_Larp4b attenuated Ang II-induced CH.
• Circ_Larp4b acts as a sponge for miR-298-5p, which in turn targets Mef2c.
• Overexpression of Mef2c counteracted the effects of miR-298-5p on cell size in the CH model.

Conclusions:

• Circ_Larp4b promotes cardiac hypertrophy by modulating the miR-298-5p/Mef2c pathway.
• Circ_Larp4b represents a potential therapeutic target for managing cardiac hypertrophy and heart failure.