Abstract
Heat shock cognate protein 70 (HSC70), a molecular chaperone, is constitutively expressed by mammalian cells to regulate various cellular functions. It is associated with many diseases and is a potential therapeutic target. Although HSC70 also possesses an anti-inflammatory action, the mechanism of this action remains unclear. This current study aimed to assess the anti-inflammatory effects of HSC70 in murine macrophages RAW 264.7 exposed to lipopolysaccharides (LPS) and to explain its pathways. Mouse macrophages (RAW 264.7) in 0.1 µg/mL LPS incubation were pretreated with recombinant HSC70 (rHSC70) and different assays (Griess assay, enzyme-linked immune assay/ELISA, electrophoretic mobility shift assay/EMSA, gelatin zymography, and Western blotting) were performed to determine whether rHSC70 blocks pro-inflammatory mediators. The findings showed that rHSC70 attenuated the nitric oxide (NO) generation, tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) expressions in LPS-stimulated RAW264.7 cells. In addition, rHSC70 preconditioning suppressed the activities and expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9. Finally, rHSC70 diminished the nuclear translocation of nuclear factor-κB (NF-κB) and reduced the phosphorylation of extracellular-signal regulated kinases 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinases (MAPK), and phosphatidylinositol-3-kinase (PI3K/Akt). We demonstrate that rHSC70 preconditioning exerts its anti-inflammatory effects through NO production constriction; TNF-α, and IL-6 suppression following down-regulation of inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), and MMP-2/MMP-9. Accordingly, it ameliorated the signal transduction of MAPKs, Akt/IκBα, and NF-κB pathways. Therefore, extracellular HSC70 plays a critical role in the innate immunity modulation and mechanisms of endogenous protective stimulation.
Highlights
Heat shock cognate protein 70 (HSC70) (73 kDa) is one of the four major members of the heat shock proteins (HSPs), which is a constitutively expressed molecular chaperone located in various cellular locations such as the nucleus and cytoplasm [1]
Effects of recombinant HSC70 (rHSC70) on LPS-Induced inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) Expression of COX-2 was attenuated in the pretreatment with rHSC70 at 1 and 5 μg/mL as a comparison with depicted in Figure 1A, iNOS was upregulated following LPS treatment (0.1 μg/mL) alone theAs control group
Our findings provided a novel evidence suggesting that p38 mitogen-activated protein kinases (MAPK) and extracellular-signal regulated kinases 1/2 (ERK1/2) are involve in the pathways of HSC70-induced macrophages stimulated by LPS
Summary
HSC70 (73 kDa) is one of the four major members of the heat shock proteins (HSPs), which is a constitutively expressed molecular chaperone located in various cellular locations such as the nucleus and cytoplasm [1]. HSC70 is a well-defined ATP binding chaperone and displays intrinsic ATPase activity which can hydrolyze ATP into ADP [5]. HSC70 is abundantly expressed and comprises approximately 1% of the total protein. HSC70 can transverse out of and return to the nucleus to and from the cytoplasm. Cellular stress such as heat shock or oxidative stress produced by H2 O2 stimulate
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
