Heat shock proteins were involved in the adaptive cytoprotection of H_2O_2 preconditioning mediated by nuclear factor-κB

Objective To investigate whether heat shock proteins (HSPs) were involved in the cytoprotection of H2O2 preconditioning mediated by Nuclear factor-κB (NF-κB). Methods The percent of apoptotic cells was measured by propidium iodide stain flow cytometry (FCM), the level of NF-κB expression was detected by Western blot assay, and the nuclear translocation of NF-κB p65 was assessed by immuno-cytochemical staining. Results The preconditioning of H2O2 at 100 μM markedly reduced PC 12 cells apoptosis induced by 300 μmol / L H2O2, and significantly enhanced expression and nuclear translocation of NF-κB p65. Furthermore, 100 μmol / L H2O2 preconditioning also up-regulated expression of HSP70 and HSP90. N-tosyl-L-phenylalanine chloromethyl ketone (TPCK), an inhibitor of NF-κB blocked the overexpression of NF-κB, HSP70 and HSP90 induced by H2O2 preconditioning, accompanied with attenuation of H2O2 preconditioning-induced cytoprotectioin. Conclusion HSP70 and HSP90 participated in the adaptive cytoprotection of H2O2 preconditioning mediated by NF-κB pathway.