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MicroRNA-133 modulates the β1-adrenergic receptor transduction cascade.

Authors :: Castaldi A
Zaglia T
Di Mauro V
Carullo P
Viggiani G
Borile G
Di Stefano B
Schiattarella GG
Gualazzi MG
Elia L
Stirparo GG
Colorito ML
Pironti G
Kunderfranco P
Esposito G
Bang ML
Mongillo M
Condorelli G
Catalucci D
Source :: Circulation research [Circ Res] 2014 Jul 07; Vol. 115 (2), pp. 273-83. Date of Electronic Publication: 2014 May 07.
Publication Year :: 2014
Abstract: Rationale: The sympathetic nervous system plays a fundamental role in the regulation of myocardial function. During chronic pressure overload, overactivation of the sympathetic nervous system induces the release of catecholamines, which activate β-adrenergic receptors in cardiomyocytes and lead to increased heart rate and cardiac contractility. However, chronic stimulation of β-adrenergic receptors leads to impaired cardiac function, and β-blockers are widely used as therapeutic agents for the treatment of cardiac disease. MicroRNA-133 (miR-133) is highly expressed in the myocardium and is involved in controlling cardiac function through regulation of messenger RNA translation/stability.<br />Objective: To determine whether miR-133 affects β-adrenergic receptor signaling during progression to heart failure.<br />Methods and Results: Based on bioinformatic analysis, β1-adrenergic receptor (β1AR) and other components of the β1AR signal transduction cascade, including adenylate cyclase VI and the catalytic subunit of the cAMP-dependent protein kinase A, were predicted as direct targets of miR-133 and subsequently validated by experimental studies. Consistently, cAMP accumulation and activation of downstream targets were repressed by miR-133 overexpression in both neonatal and adult cardiomyocytes following selective β1AR stimulation. Furthermore, gain-of-function and loss-of-function studies of miR-133 revealed its role in counteracting the deleterious apoptotic effects caused by chronic β1AR stimulation. This was confirmed in vivo using a novel cardiac-specific TetON-miR-133 inducible transgenic mouse model. When subjected to transaortic constriction, TetON-miR-133 inducible transgenic mice maintained cardiac performance and showed attenuated apoptosis and reduced fibrosis compared with control mice.<br />Conclusions: miR-133 controls multiple components of the β1AR transduction cascade and is cardioprotective during heart failure.<br /> (© 2014 American Heart Association, Inc.)