Cardioprotection during myocardial infarction in diabetic cardiomyopathy
Diabetic patients are at an increased risk of diabetic cardiomyopathy (DCM) and acute myocardial infarction (AMI). Protecting the heart against AMI is more challenging in DCM than non-diabetic hearts. We investigated whether intravenous atorvastatin administration during AMI exerts cardioprotection in DCM as seen in non-diabetic hearts.
Sprague-Dawley rats were divided into streptozotocin-induced DCM and normoglycemic-control groups. Our model of DCM rats exhibited interstitial fibrosis and cardiac dysfunction at 5 weeks. At this time point, all animals underwent AMI-induction (coronary ligation for 45min), receiving intravenous atorvastatin or vehicle during ischemia. Animals were reperfused and sacrificed 24h later for myocardial infarct size analysis and cardiac tissue sampling. Echocardiography was performed.
DCM vehicle rats had larger infarcts than normoglycemic vehicle-treated animals at comparable area-at-risk. Intravenous atorvastatin reduced infarct size and preserved systolic function in both groups. In comparison to vehicle animals, intravenous atorvastatin inhibited RhoA membrane translocation, induced AMPK phosphorylation, prevented apoptosis execution and improved cardiac remodelling in the infarcted heart of both groups whereas innate immune cell infiltration was further reduced in intravenous atorvastatin-treated DCM animals.
The proven cardioprotective effectiveness of this intravenous statin formulation in the presence of DCM warrants its further development into a clinically therapeutic option.
