Effects of heat shock protein 70 activator SW02 on lipopolysaccharide-induced expression of inducible nitric oxide synthase in macrophages / 中国药理学通报

ABSTRACT

Aim To observe the effects of heat shock protein 70 ( Hsp70 ) activator SW02 on lipopolysaccha-ride( LPS)-induced expression of inducible nitric oxide synthase ( iNOS ) and LPS-induced production of nitric oxide ( NO ) in macrophages. Methods RAW264. 7 cells were stimulated by LPS, and were divided into DMSO,DMSO+LPS(1 mg·L-1),SW02,and SW02+LPS ( 1 mg · L-1 ) groups. The protein expression was detected by Western blot. NO concentration was measured by Griess kit. The iNOS mRNA was detected by real-time PCR. The NF-κB binding to iNOS promot-ers was measured by chromatin immunoprecipitation ( ChIP ) assays. Results SW02 significantly blocked the protein and mRNA expression of iNOS as well as the production of NO in LPS-stimulated RAW264 . 7 cells(P0. 05 , SW02 +LPS group vs DMSO+LPS group ) and nuclear translocation of NF-κB ( P > 0. 05 , SW02 + LPS group vs DMSO + LPS group) . However,SW02 reduced the NF-κB binding to iNOS promoters inside the cell( P<0. 05,SW02+LPS group vs DMSO+LPS group) . Conclusion These re-sults show that SW02 prevents iNOS expression and NO induction likely through attenuation of the NF-κB bind-ing to iNOS promoters in macrophages.