Hirsutine ameliorates myocardial ischemia-reperfusion injury through improving mitochondrial function via CaMKII pathway

ABSTRACT

Acute myocardial infarction (AMI) is the leading cause of death worldwide. Ischemia-reperfusion (I/R) injury is considered the most common contributor to AMI. Hirsutine has been shown to protect cardiomyocytes against hypoxic injury. The present study investigated whether hirsutine improved AMI induced by I/R injury and the underlying mechanisms. In our study, we used a rat model of myocardial I/R injury. The rats were given hirsutine daily (5, 10, 20 mg/kg) by gavage for 15 days before the myocardial I/R injury. Detectable changes were observed in myocardial infarct size, mitochondrial function, histological damage, and cardiac cell apoptosis. According to our findings, hirsutine pre-treatment reduced the myocardial infarct size, enhanced cardiac function, inhibited cell apoptosis, reduced the tissue lactate dehydrogenase (LDH) and reactive oxygen species (ROS) content, as well as enhanced myocardial ATP content and mitochondrial complex activity. In addition, hirsutine balanced mitochondrial dynamics by increasing Mitofusin2 (Mfn2) expression while decreasing dynamin-related protein 1 phosphorylation (p-Drp1), which was partially regulated by ROS and calmodulin-dependent protein kinase II phosphorylation (p-CaMKII). Mechanistically, hirsutine inhibited mitochondrial-mediated apoptosis during I/R injury by blocking the AKT/ASK-1/p38 MAPK pathway. This present study provides a promising therapeutic intervention for myocardial I/R injury.

KEYWORDS:

• Hirsutine
• myocardial ischemia-reperfusion injury
• mitochondria
• apoptosis

Acknowledgments

The authors acknowledge that the Central Laboratory of Xinjiang Medical University has provided the professional assistance in ultrasound imaging system.

Author contributions

WJ, YZ and JC designed the study. WJ, YZ, WZ and JC wrote the manuscript. WJ and JC acquired funding for the study. WJ, YZ, WZ, XP, JL and QC acquired and analyzed the data.

Disclosure statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Availability of data and materials

The data sets used and/or analyzed during this study are available from the corresponding author on reasonable request.

Additional information

Funding

The National Natural Science Foundation: Mechanisms of the Protective Effects of Tilianin Against Myocardium Ischemia/Reperfusion Injury Through Ox-CaMKII-mediated Mitochondrial Regulating Pathway (No. 81760045).