Heat shock proteins and their expression in primary murine cardiac cell populations during ischemia and reperfusion.

A tight quality control system over protein folding, turnover and synthesis, involving molecular chaperones and co-chaperones, maintains the balance of cardiac proteins. Various cardiac pathologies, including myocardial infarction, increase stresses and post-translational modifications favoring misfolding due to an overwhelmed quality control system. The toxic nature of accumulated misfolded proteins further worsens the condition. The important molecular chaperones which act as quality control proteins are involved in protecting the heart, these include heat shock protein70 (HSP70) and HSP90. Here, we review the emerging roles of heat shock proteins in the maintenance of cardiac cell populations in experimental models of ischemia/reperfusion (I/R) injury. Furthermore, we discuss the expression of HSP70 and HSP90 with therapeutic and diagnostic considerations. Although there is only a partial understanding of these important HSPs in I/R injury, there is an immense therapeutic potential of modulating these HSPs to counteract the imbalance between misfolding and endogenous protein quality control systems.