Altered expression of constitutive type and inducible type heat shock proteins in response of D-galactosamine-sensitized mice to lipopolysaccharide as an experimental endotoxic shock model

The expression of heat shock proteins (HSPs) as stress-induced proteins was studied in mice injected with D-galactosamine (D-GalN) and lipopolysaccharide (LPS) as an experimental endotoxic shock model. The expression of constitutive type heat shock protein 70 (HSC70) was significantly reduced in livers of mice injected with D-galactosamine and lipopolysaccharide, while its expression was unaffected in livers of mice injected with D-galactosamine or lipopolysaccharide alone. The expression of other constitutive type heat shock proteins, namely HSP60, HSP32 and HSP25 was also reduced in mice injected with D-galactosamine and lipopolysaccharide. On the other hand, inducible type HSP70 was detected in livers from mice injected with D-galactosamine and lipopolysaccharide, but not in livers from mice injected with D-galactosamine or lipopolysaccharide alone. Simultaneous injection of anti-tumor necrosis factor (TNF)-α antibody prevented the liver from reduced expression of constitutive type HSC70, and lead to marked expression of inducible type HSP70 in the liver. Reduced expression of constitutive type HSC70 was also found when D-galactosamine and recombinant TNF-α was injected. Therefore, TNF-α was suggested to play a critical role on altered expression of constitutive HSC70 and inducible type HSP70 in response of D-galactosamine-sensitized mice to lipopolysaccharide.