Expression of heat shock protein 27 correlates with actin cytoskeletal dynamics and contractility of cultured human bladder smooth muscle cells

Heat shock protein 27 (HSP27) is one of the most important chaperone proteins that modulates smooth muscle contraction. Here we investigated the effects of HSP27 expression on cytoskeleton dynamics and contractile function of human bladder smooth muscle cells (BSMCs) in vitro. Cultured human BSMCs were transfected with lentiviral vectors expressing either HSP27 or HSP27-siRNAs. Normal BSMCs cells and cells transfected with the empty lentivirus were used as control. Cells were then cultured on Flexcell flexible membrane dishes and mechanical stretch (14.8% elongation) was applied. The stretch caused significant disruption of actin cytoskeletal structure and decrease in F/G-actin ratio in BSMCs with HSP27 over-expression, knock-down and control groups (P