Protective effect of heat shock proteins: potential for gene therapy

The heat shock proteins (hsps) are expressed in normal cells but their expression is enhanced by a number of different stresses including heat and ischaemia. They play important roles in chaperoning the folding of other proteins and in protein degradation. In the heart and the brain, a number of studies have shown that prior induction of the hsps by a mild stress has a protective effect against a more severe stress. Moreover, over-expression of an individual hsp in cardiac or neuronal cells in culture and in the intact heart or brain of either transgenic animals or using virus vectors, also produces a protective effect, directly demonstrating the ability of the hsps to produce protection. These findings indicate the potential importance of developing procedures for elevating hsp expression in a safe and efficient manner in human individuals using either pharmacological or gene therapy procedures.