Intravenous AAV8 Encoding Urocortin-2 Increases Function of the Failing Heart in Mice.

Abstract

Urocortin-2 (UCn2) peptide infusion increases cardiac function in patients with heart failure, but chronic peptide infusion is cumbersome, is costly, and provides only short-term benefits. Gene transfer would circumvent these shortcomings. We previously showed that a single intravenous (IV) injection of AAV8.UCn2 increases plasma UCn2 and left ventricular (LV) systolic and diastolic function for at least 7 months in normal mice. Here we test the hypothesis that IV delivery of AAV8.UCn2 increases function of the failing heart. Myocardial infarction (MI, by coronary ligation) was used to induce heart failure, which was assessed by echocardiography 3 weeks after MI. Mice with LV ejection fraction (EF) <25% received IV delivery of AAV8.UCn2 (5×10(11) gc) or saline, and 5 weeks later echocardiography showed increased LV EF in mice that received UCn2 gene transfer (p=0.01). In vivo physiological studies showed a 2-fold increase in peak rate of LV pressure development (LV +dP/dt; p<0.0001) and a 1.6-fold increase in peak rate of LV pressure decay (LV -dP/dt; p=0.0007), indicating increased LV systolic and diastolic function in treated mice. UCn2 gene transfer was associated with increased peak systolic Ca(2+) transient amplitude and rate of Ca(2+) decline and increased SERCA2a expression. In addition, UCn2 gene transfer reduced Thr286 phosphorylation of Cam kinase II, and increased expression of cardiac myosin light chain kinase, findings that would be anticipated to increase function of the failing heart. We conclude that a single IV injection of AAV8.UCn2 increases function of the failing heart. The simplicity of IV injection of a vector encoding a gene with beneficial paracrine effects to increase cardiac function is an attractive potential clinical strategy.

• Authors: N Chin Lai, Mei Hua Gao, Dimosthenis Giamouridis, Jorge Suarez, Atsushi Miyanohara, Jay Parikh, Stephen Hightower, Tracy Guo, Wolfgang Dillmann, Young-Chul Kim, Julieta Diaz-Juarez, H Kirk Hammond
• Journal: Human gene therapy (Hum Gene Ther) Vol. 26 Issue 6 Pg. 347-56 (Jun 2015) ISSN: 1557-7422 [Electronic] United States
• PMID: 25760560 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Urocortins
• urocortin 2, mouse
• Corticotropin-Releasing Hormone
• Cyclic AMP
• Cyclic AMP-Dependent Protein Kinases
• Calcium

Topics

• Animals
• Blood Pressure (genetics)
• Calcium (metabolism)
• Corticotropin-Releasing Hormone (administration & dosage, genetics, metabolism)
• Cyclic AMP (metabolism)
• Cyclic AMP-Dependent Protein Kinases (metabolism)
• Dependovirus (genetics)
• Electrocardiography
• Genetic Therapy (methods)
• Genetic Vectors (administration & dosage, genetics)
• Heart Failure (physiopathology, therapy)
• Heart Rate (genetics)
• Humans
• Injections, Intravenous
• Liver (pathology)
• Male
• Mice, Inbred C57BL
• Urocortins (administration & dosage, genetics, metabolism)
• Ventricular Function, Left (genetics)