Effect of Irisin on Pressure Overload-Induced Cardiac Remodeling.

BACKGROUND: Irisin has been considered a prognostic factor in several cardiovascular diseases. Nevertheless, no data are available on the role of irisin in cardiac remodeling. AIM OF THE STUDY: This study aimed to determine the potential role of irisin in cardiac remodeling and explore potential mechanisms. METHODS: A total of 40 rats that underwent transverse abdominal aortic constriction (TAC) surgery or sham operation were divided into four groups: sham + saline (NS), sham + irisin, TAC + NS, and TAC + irisin. After 6 weeks of treatment, echocardiography was performed to assess in vivo cardiac morphology. The left ventricular myocardium was prepared and observed by pathological examination. The effect of irisin on cardiomyocyte apoptosis and the expression of oxidative stress and cardiac hypertrophy markers were observed. Then, the effect of irisin on the Akt signaling system was also detected. RESULTS: The rats in the TAC group displayed obvious signs of cardiac dysfunction and cardiac hypertrophy, and irisin treatment could reverse these changes. Irisin could inhibit the expression of nicotinamide adenine dinucleotide phosphate oxidase 2 and xanthine oxidase in TAC rats and increase the expression of antioxidant enzymes. Furthermore, the expression of phosphorylated protein kinase B (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), and phosphorylated glycogen synthase kinase 3ß (p-GSK3ß) was much higher in the cardiac remodeling groups (p <0.05 vs. sham rats). Irisin could relieve the inhibition effect and reduce the expression level of these three proteins. CONCLUSIONS: Irisin treatment could significantly improve cardiac remodeling by inhibiting oxidative stress via attenuating the Akt signaling activation.