Increased expression of HSP27 protects canine myocytes from simulated ischemia-reperfusion injury.

Previous studies have shown that adult rat myocytes can be protected from simulated ischemia-reperfusion (I/R) injury by small heat shock proteins (sHSPs). However, to date the cardioprotective effect of sHSPs has not been confirmed in adult myocytes from a large animal species. Left ventricular myocytes from adult dogs were cultured and infected with a replication-deficient adenovirus designed to increase expression of the human form of HSP27. The response to simulated I/R injury was compared using morphologic criteria. Virus-infected myocytes expressed two- to threefold more HSP27 and sustained less injury in response to simulated I/R than control cells (P < 0.001; paired t-test). Canine myocytes can be isolated, cultured, and induced to increase the expression of a foreign protein without significant effects on differentiation and/or viability. Increased expression of HSP27 provides significant protection from simulated I/R injury in adult canine myocytes. Determining the mechanism by which sHSPs protect from lethal cell injury will provide important new insights into the mechanism of irreversible cell injury in adult myocardium.