Inactivation of Notch1-TGF-β-Smads Signaling Pathway by Atorvastatin Improves Cardiac Function and Hemodynamic Performance in Acute Myocardial Infarction Rats.

Introduction: The aim of this study was to determine the effects of atorvastatin on cardiac function and hemodynamics and to investigate its functional mechanism on cardiac fibrosis in acute myocardial infarction (AMI) rats.

Methods: Cardiac functions and hemodynamic changes were evaluated in each group on day 28. Quantitative reverse transcription-polymerase chain reaction, Western blot, and immunohistochemistry were performed to detect the expression of notch1, transforming growth factor-β (TGF-β), Smad2, Smad7, as well as myocardial fibrosis factors (i.e., collagen I, collagen III, and galectin-3) in the myocardial tissues of AMI rats. The changes of myocardial cell structure and myocardial collagen fibers of AMI rats were observed with hematoxylin and eosin staining and Masson staining.

Results: Atorvastatin improved the cardiac function and hemodynamic performance. Atorvastatin downregulated the expression of notch1, smad2, collagen I, and collagen III in AMI rats. Atorvastatin treatment decreased the transcription of notch1, TGF-β, and smad2, while it increased smad7 in AMI rats. Atorvastatin induced the downregulation of collagen I, collagen III, and galectin-3. Myocardial immunohistochemical analysis showed atorvastatin inhibited the expression of notch1, TGF-β, and smad2 in myocardial tissues.

Conclusion: Atorvastatin inhibited myocardial fibrosis by interfering with notch1-TGF-β-smads signal pathways. In addition, it could mitigate myocardial remodeling and improve cardiac functions and hemodynamics.