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Objective To explore the expression changes of HSP90αin cardiac muscles and survival rates in rats by using the different fluids to resuscitate the severs hemorrhagic shocked rats ,and provide reference for the clinical treatment of hemorrhagic shock with different resuscitation fluids .Methods Uncontrolled hemorrhagic shock rats model was established ,using lactic acid salinger liquid ,poly peptide injection gelatin ,hypertonic sodium chloride dextran for fluid resuscitation respectively ,and then checked the HSP90αexpression changes and survival rates in rats .Results the expressions of HSP90αin myocardial tissue and the mortality in rats were different after using different resuscitation fluids in severe hemorrhagic shock rats ,difference was statistically significant(P<0 .05) .Conclusion the expression of HSP90α in cardiac muscles of rats could be induced by severe hemorrhagic shock ,the HSP90αexpressed differently and regularly after using different resuscitating fluids ,it implied that the HSP90α played an important role in the hemorrhagic rats cardiac as a regulating fator .
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AIM: To explore the roles of heat shock protein 90 (HSP90) in the blockage of hydrogen sulfide (H2S) against chemical hypoxia-mimetic agent (cobalt chloride, CoCl_2)-induced oxidative stress injuries in H9c2 cardiac cell. METHODS: H9c2 cells were treated with CoCl_2 to set up the chemical hypoxia-induced the model of cardiomyocyte injury. Sodium hydrosulfide (NaHS, a H2S donor) was added into medium for 30 min before CoCl_2 treatment. ATP content was detected by high performance liquid chromatogram (HPLC). Mitochondrial membrane potential (MMP) was measured by rhodamine123 (Rh123) staining and photofluorography. The activity of superoxide dismutase (SOD) was observed using a SOD kit. The expression of heme oxygenase-1 (HO-1) was evaluated by Western blotting. RESULTS: CoCl_2 at concentration of 600 μmol/L significantly reduced SOD activity, ATP level and MMP, and enhanced the expression of HO-1 in H9c2 cells. Pretreatment with 400 μmol/L NaHS dramatically inhibited the cytotoxicity induced by CoCl_2, increased SOD activity, ATP level and MMP, decreased HO-1 expression. 17-allylamino-17 demethoxygeldanamycine(17AAG), an inhibitor of HSP90, obviously blocked the inhibitory effect of H2S on the CoCl_2-induced cytotoxicity, reduced the levels of ATP and MMP, increased HO-1 expression. However, no significantly influence on SOD activity was observed. CONCLUSION: HSP90 may mediate the cardioprotection of H2S via inhibiting the oxidative stress induced by chemical hypoxia.
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Objective To investigate the effects of macmphage migration inhibitory factor (MIF) on glucocorticoid (GC) re]ease and glucocorticoid recer (GR) in mts.Methods Test Ⅰ Thirty-two male SD rats weighing 250-300 g were randomly divided into 4 groups(n=8 each):control group(C),low dose recombinant MIF (rMIF) group (rMIF-L),middle dose rMIF group (rMIF-M) and high dose rMIF group (rMIF-H).The animals received l ml normal saline via the right femoral vein in group C.The animals received rMIF50.100 and 200 ng in l ml normal saline though right femoral vein in group rMIF-L,rMIF-M or rMIF-H respectively.Blood samples were taken from left femoral artery immediately before inection(T0,baseline),and at 5 min,3 h,6 h.12 h and 24 h after injection of rMIF(T1-5) for determination of serum concentration of corticosterone.Test Ⅱ Primary cultured neonate rat(2-3 days)myocardial ceils were randomly divided into 3 groups(n=24 each):group C,group rMIF-L and group rMIF-M.The ceUs in group C,rMIF-L and rMIF-M wefe incubated with DMEM.rMIF 50 ng+DMEM and rMIF 100 ng+DMEM for 3 h respectively.The expression of GR and HsPg0 wag determined by Western blot.ResuBs Test Ⅰ The serum concentration of corticosterone was signifieemily higher in the other 3 groups than in group C at T1-5(P<0.05).The sertlm concentration of corticostemne was significantly increased at T1-5 in group rMIF-L,rMIF-M and rMIF-H compared with the baseline values(P<0.05).Test Ⅱ HSP90 expresion was significantly lower in the other two groups than in group C(P<0.05).Them was rio signifieanf difference in HSP90 expression between group rMIF-L and group rMIF-M(P>0.05).There was no significant difference in GR expression among the 3 groups ( P > 0.05). Conclusion MIF druing sepsis can weaken GR function through down-regulating HSP9O expression, resulting in CC resistance.
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Objective: To study the immunotherapeutic effect on the esopgageal adenocarcinoma mediated by gp96-peptide complexes isolated from the same kind of tumor. Methods: gp96- peptide complexes were purified from nude mice tumors burdened by subcutaneous injection of human esophageal adenocarcinoma cell line SEG-1 . gp96-peptide complexes were carried by the dendritic cells(DC) induced from human peripheral blood mononuclear cells to prepare gp96-DC vaccine. The proliferation of lymphocytes was tested with trypan-blue stain. The quantity of interferon-?(IFN-?) released from cytotoxic T lymphocytes (CTL) was detected with ELISA method. The killing effect of CTL on target cell SEG-1 was measured with MTT. Results: We obtained 120 ?g gp96 from 55 g tumor tissue. DC, gp96, and gp96-DC all could elicit the proliferation of lymphocytes and make them becoming into CTL which released IFN-? and showed different degrees of killing effect on target cell SEG-1. gp96-DC has the strongest eliciting effect among them. At the ratio of E(effect) to T(target) as 40∶1,the killing rate was 68%.No significant difference between the effects of CTL induced by DC alone and of lymphocytes without specific antigen on SEG-1 and K562 cells. Conclusion: The gp96-peptide complexes from tumors can improve the effect of eliciting lymphocyte proliferation of DC and make the lymphocyte becoming into CTL more effectively.These CTLs show prominent killing effect on the target tumor cells.
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AIM: To find the role of heat shock protein 90(HSP90) and tubulin in oxidative stress preconditioning in HepG2 cells.METHODS: The different doses of H2O2 were used to induce cell injury in HepG2 cells.MTT assay,Western blotting and confocal laser microscopy were also used.RESULTS: MTT colorimetry showed that preconditioning(50 mmo1/L H2O2) provided a temporary resistance against subsequent oxidative stress(500 mmol/L H2O2).Western blotting demonstrated that preconditioning increased the levels of HSP90 and tubulin in HepG2 cells,and lessen the declining of HSP90 and tubulin after stress.Tubulin and HSP90's colocalizations in cells with different doses of H2O2 were also observed under laser scanning confocal microscope.CONCLUSION: Tubulin might play important role in oxidative stress preconditioning in HepG2 cells by combining with HSP90.
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AIM: To establish a HSP90 highly expressing cell line and study the effect of high level of HSP90 on cell stress response. METHODS: The recombined plasimid pSmycHSP, which contains the full length DNA coding for human HSP90?, was introduced into mouse fibroblast cell line NIH-3T3 by electroporation after being subcloned, purified and identified by limited enzyme digestion. Screened by G418, the positive clones were selected and identified by immunofluorescence, immunocytochemistry and Western-blotting. NIH-3T3 cells transfected with empty plasmid served as control, hyperthermia(44 ℃, 20 min, 40 min)was used to simulate oxidative stress. The activity of lactate dehydrogenase (LDH) in supernatant and damage of DNA were detected by automatic biochemistry analyzer and flow cytometer separately to analyze the effect of high-level HSP90 on cell membrane and DNA injuries under stress condition. RESULTS: The rising level of HSP90 was shown by immunofluorescence, immunocytochemistry and Western-blotting in HSP90 overexpressing cell line. There was no difference in the leakage of LDH between HSP90 overexpressing cell line and control, but the damage of DNA was more severe at 44 ℃for 20 min in HSP90 overexpressing cell line than control. Compared with control, the above indices were relieved at 44 ℃ for 40 min in HSP90 overexpressing cell line. CONCLUSION: The NIH-3T3 derived cell line, which stably expressed high level of HSP90, was established. The effect of high-level HSP90 on cells is complex at different intensity of stress, and the protection may be shown at more severe stress circumstance.