Cardiac contractility modulation improves left ventricular systolic function partially via miR-25 mediated SERCA2A expression in rabbit trans aortic constriction heart failure model

The purpose of this study was to investigate the underlying mechanism of cardiac contractility modulation (CCM) in improving trans aortic constriction (TAC)-induced heart failure (HF) left ventricular (LV) systolic function. A total of 25 New Zealand white rabbits were randomly divided into 5 groups: sham operation group (SHM), TAC-induced HF group (HF), TAC-induced HF followed by CCM stimulation group (HF + CCM), TAC-induced HF followed by injection of anti-miR-25 group (HF + anti-miR-25), TAC-induced HF followed by CCM stimulation and AAV9-miR-25 injection group (HF + CCM + miR-25). CCM current was performed 6 hours a day for 4 weeks. The left ventricle ejection fraction (LVEF) was measured by ultrasound. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used for measuring RNA and protein levels. The sarcoplasmic reticulum calcium ATPase (SERCA2A) and LVEF were reduced, while the miR-25 expression was improved in HF group compared to SHM group. Conversely, the SERCA2A and LVEF were improved, and the miR-25 reduced in the HF + CCM and the HF + anti-miR-25 groups compared to the HF group. Moreover, the SERCA2A and LVEF were reduced, while the miR-25 was improved in the HF + CCM + miR-25 group compared to the HF + CCM group. CCM is a potentially effective procedure for improving LV systolic function, which might partially by inhibiting miR-25 expression, further improved SERCA2A expression in TAC HF models.