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<p><b>BACKGROUND</b>Nucleolin (NCL) is the most abundant RNA-binding protein in the cell nucleolus and plays an important role in chromatin stability, ribosome assembly, ribosomal RNA maturation, ribosomal DNA transcription, nucleocytoplasmic transport, and regulation of RNA stability and translation efficiency. In addition to its anti-apoptotic properties, the underlying mechanisms associated with NCL-related roles in different cellular processes remain unclear. In this study, the effect of NCL on microRNA (miRNA) expression was evaluated by generating transgenic mice with myocardial overexpression of NCL and by analyzing microarrays of mature and precursor miRNAs from mice.</p><p><b>METHODS</b>Using microinjection of alpha-MyHc clone 26-NCL plasmids, we generated transgenic mice with myocardial overexpression of NCL firstly, and then mature and precursor miRNAs expression profiles were analyzed in NCL transgenic mice (n = 3) and wild-type (WT) mice (n = 3) by miRNA microarrays. Statistical Package for the Social Sciences version 16.0 software (SPSS, Inc., Chicago, IL, USA) was used to perform Student's t-test, and statistical significance was determined at P < 0.05.</p><p><b>RESULTS</b>Several miRNAs were found to be differentially expressed, of which 11 were upregulated and 4 were downregulated in transgenic mice with myocardial overexpression of NCL compared to those in WT mice. Several differentially expressed miRNAs were subsequently confirmed and quantified by real-time quantitative reverse transcription-polymerase chain reaction. Bioinformatics analysis was used for the prediction of miRNA targets. Furthermore, in vitro experiments showed that NCL regulated miR-21 expression following hydrogen peroxide preconditioning.</p><p><b>CONCLUSIONS</b>Myocardial-protection mechanisms exerted by NCL might be mediated by the miRNAs identified in this study.</p>
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AIM:To observe the expression of microRNA-126-5p during myocardial injury and its role in myo-cardial cell injury induced by adriamycin(also called doxorubicin, DOX).METHODS: The BALB/c mouse model of DOX-induced acute and chronic myocardial injury was established via intraperitoneal injection of DOX.HE staining was applied to observe the morphological changes of myocardial tissues.Lactate dehydrogenase(LDH)in serum was detected and PowerLab system was used to detect the influence of DOX on the changes of ±dp/dtmax.The expression of microRNA-126-5p in injured myocardial tissues and the H 9c2 cells exposed to DOX was detected by real-time PCR.Gain-and loss-of-function experiments were conducted to detect the role of microRNA-126-5p in H9c2 cells treated with DOX on LDH release and caspase-3 activation.RESULTS:In acute and chronic DOX myocardial damage models in mice,HE staining showed disarranged myocardial fibers, dissolved myofibril and inflammatory cell infiltration.Higher serum LDH level and lower ±dp/dtmaxin DOX-treated mice than those in normal mice were found.Compared with the normal mice, the expression level of microRNA-126-5p was significant increased in the myocardium with DOX-induced injury.Similarly,the expression level of microRNA-126-5p was significant increased in the H9c2 cells treated with DOX.In addition, over-expression of microRNA-126-5p decreased cell viability and promoted apoptosis,while microRNA-126-5p ablation promoted the viability and inhibited the apoptosis of H9c2 cells.CONCLUSION:The microRNA-126-5p expression is up-regulated in myocar-dial injury induced by DOX,and microRNA-126-5p inhibits cell viability and promotes apoptosis induced by DOX.
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Cardiomyocytes can resist ischemia/reperfusion (I/R) injury through ischemic postconditioning (IPoC) which is repetitive ischemia induced during the onset of reperfusion. Myocardial ischemic preconditioning up-regulated protein 2 (MIP2) is a member of the WD-40 family proteins, we previously showed that MIP2 was up-regulated during ischemic preconditioning (IPC). As IPC and IPoC engaged similar molecular mechanisms in cardioprotection, this study aimed to elucidate whether MIP2 was up-regulated during IPoC and contributed to IPoC-mediated protection against I/R injury. The experiment was conducted on two models, an in vivo open chest rat coronary artery occlusion model and an in vitro model with H9c2 myogenic cells. In both models, 3 groups were constituted and randomly designated as the sham, I/R and IPoC/hypoxia postconditioning (HPoC) groups. In the IPoC group, after 45 min of ischemia, hearts were allowed three cycles of reperfusion/ischemia phases (each of 30 s duration) followed by reperfusion. In the HPoC group, after 6 h of hypoxia, H9c2 cells were subjected to three cycles of 10 minute reoxygenation and 10 minute hypoxia followed by reoxygenation. IPoC significantly reduced the infarct size, plasma level of Lactate dehydrogenase and creatine kinase MB in rats. 12 h after the reperfusion, MIP2 mRNA levels in the IPoC group were 10 folds that of the sham group and 1.4 folds that of the I/R group. Increased expression of MIP2 mRNA and attenuation of apoptosis were similarly observed in the HPoC group in the in vitro model. These effects were blunted by transfection with MIP2 siRNA in the H9c2 cells. This study demonstrated that IPoC induced protection was associated with increased expression of MIP2. Both MIP2 overexpression and MIP2 suppression can influence the IPoC induced protection.
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Animales , Masculino , Ratas , Western Blotting , Hipoxia de la Célula/genética , Línea Celular , Supervivencia Celular/genética , Citometría de Flujo , Precondicionamiento Isquémico Miocárdico/métodos , Miocitos Cardíacos/metabolismo , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Daño por Reperfusión/metabolismoRESUMEN
OBJECTIVE@#To explore the role of cell-surface nucleolin in lipopolysaccharide (LPS)-stimulated expression and secretion of TNF-alpha and IL-1beta in human THP-1 monocytes.@*METHODS@#Immuno-fluorescence assay and Western blot were used to identify the expression of nucleolin on the surface of THP-1 monocytes. Inactivation of nucleolin was induced by anti-nucleolin monoclonal antibody blockage, and the expression and secretion of TNF-alpha and IL-1beta were observed by using reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immuno-sorbent assay (ELISA)respectively in LPS-mediated human THP-1 monocyte inflammatory model.@*RESULTS@#Immuno-fluorescence showed that nucleolin was localized on the cell surface of THP-1 monocytes as indicated by dotted red fluorescence. Western blot assay indicated that nucleolin existed in the cell membrane fractions. RT-PCR assay showed that the expressions of TNF-alpha and IL-1beta mRNA significantly increased at 2 h and 3 h after the treatment with 1000 microg/L LPS. After 1 h pretreatment with anti-nucleolin antibody, the levels of TNF-alpha and IL-1beta mRNA decreased compared with an anti-nucleolin antibody untreated group and an irrelevant IgG+LPS group (P<0.05). ELISA assay showed that the pretreatment with anti-nucleolin antibody inhibited significantly the secretion of LPS-induced levels of TNF-alpha and IL-1beta after 4, 12 and 24 h treatment with 1000 microg/L LPS.@*CONCLUSION@#Nucleolin expresses on the cell surface of THP-1 monocytes and involves in the LPS-mediated expression and secretion of TNF-alpha and IL-1beta.
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Humanos , Línea Celular , Membrana Celular , Metabolismo , Interleucina-1beta , Metabolismo , Lipopolisacáridos , Farmacología , Monocitos , Biología Celular , Metabolismo , Fosfoproteínas , Metabolismo , Fisiología , Proteínas de Unión al ARN , Metabolismo , Fisiología , Factor de Necrosis Tumoral alfa , MetabolismoRESUMEN
Since the findings of Murry and Currie et al. that ischemic preconditioning (IPC) and heat shock response (HSR) could protect evidently myocardium against ischemia-reperfusion injury in the middle of 1980s, endogenous myocardial protection has drawn widespread attentions. A great quantity of studies completed during the past 25 years made much progress in endogenous myocardial protection. Abundant research experiences have been accumulated and a basic theoretical framework has been established in this field. However, there are still many questions need to be solved. In this review, we focused on clarifying some hot questions and important future directions in IPC, heat shock proteins (HSPs), research models and strategies in endogenous myocardial protection.
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Animales , Humanos , Proteínas de Choque Térmico , Fisiología , Precondicionamiento Isquémico , Precondicionamiento Isquémico Miocárdico , Daño por Reperfusión Miocárdica , Miocardio , Daño por Reperfusión , Factores de TiempoRESUMEN
OBJECTIVE@#To observe the effect of Krüppel-like factor 4 (KLF4) overexpression on heat stress-induced apoptosis of Raw264.7 macrophages.@*METHODS@#The fragment containing full length mouse KLF4 cDNA coding sequence was inserted into the pcDNA3.1 vector and Raw264.7 macrophages were transfected with pcDNA3.1-KLF4 plasmids using lipofectamine.The expression of KLF4 was examined by Western blot in the Raw264.7 macrophages stably transfected with pcDNA3.1- KLF4 plasmids. Raw264.7 cells transfected with pcDNA3.1 and pcDNA3.1-KLF4 were exposed to heat stress (42 degrees C) for 1h and recovered at 37 degrees C for 12h. Flow cytometry, Hoechest 33258 staining assay, and DNA ladder assays were performed to assess the apoptosis.@*RESULTS@#The KLF4 overexpressed Raw264.7 macrophages were established. After the heat stress, flow cytometry showed that apoptotic cells increased significantly in KLF4 overexpressed cells compared with the vector control; Hoechest 33258 staining was characterized with classical changes including apoptotic body, and nuclear condensation. Agarose gel electrophoresis showed that "DNA ladder" could be observed clearly.@*CONCLUSION@#KLF4 overexpression can increase heat stress-induced apoptosis of Raw264.7 macrophages.
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Animales , Ratones , Apoptosis , Genética , Línea Celular , Vectores Genéticos , Respuesta al Choque Térmico , Factores de Transcripción de Tipo Kruppel , Genética , Macrófagos , Biología Celular , Plásmidos , TransfecciónRESUMEN
<p><b>OBJECTIVE</b>Cytokine mediated cell immunity is the main mode of anti-tumor immunity in organism, and the disequilibrium of cytokine network is the main cause of tumor cells escaping immunologic surveillance. High mobility group box 1 (HMGB1), a nuclear protein, has recently been identified as an important mediator of local and systemic inflammatory diseases when released into the extracellular milieu. In the present study, the investigators explored the clinical significance of alteration in the serum levels of HMGB1 in childhood acute lymphocytic leukemia (ALL) and the mechanism of HMGB1-induced tumor necrosis factor (TNF)-alpha secretion in leukemic cells.</p><p><b>METHODS</b>The serum levels of HMGB1 in healthy children and childhood ALL were assayed by Western blotting. K562 leukemic cells were stimulated with recombinant HMGB1 protein in vitro, and the secretion of TNF-alpha was determined by using ELISA. The effects of HMGB1 on activation of p38, c-Jun amino-terminal kinase (JNK), and extracellular-signal regulated protein kinase (ERK) and mitogen-activated protein kinase (MAPK) in K562 cells were assayed by using Western blotting. The effects of inhibitors specific for the MAPK on HMGB1-induced TNF-alpha secretion were assayed by using ELISA.</p><p><b>RESULTS</b>The serum levels of HMGB1 were significantly higher in ALL initial treatment group (n = 15, 43.78 +/- 4.62 microg/ml) than those in healthy control group (n = 15, 0.60 +/- 0.48 microg/ml, P < 0.01) and ALL complete remission group (n = 15, 0.89 +/- 0.62 microg/ml, P < 0.01). No significant difference was found between the healthy control group and ALL complete remission group in HMGB1 levels (P > 0.05). TNF-alpha started to become detectable at 2 h and was still increasing at 16 h after HMGB1 (1 microg/ml) treatment in K562 cell culture. TNF-alpha was also secreted from K562 cells in a dose-dependent manner after HMGB1 (1 ng/ml-1 microg/ml) exposure. HMGB1 induced the phosphorylation of p38, JNK and ERK in k562 cells. Inhibitors specific for the JNK (SP600125), MEK (PD98059), and p38 MAPK (SB203580), abrogated HMGB1-induced TNF-alpha secretion.</p><p><b>CONCLUSIONS</b>The measurement of serum HMGB1 is helpful to evaluate the prognosis of the childhood ALL. HMGB1 stimulates leukemic cells to secrete TNF-alpha through a MAPK-dependent mechanism.</p>
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Niño , Humanos , Línea Celular Tumoral , Citocinas , Metabolismo , Proteína HMGB1 , Metabolismo , Imidazoles , Farmacología , Proteínas Quinasas JNK Activadas por Mitógenos , Metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos , Metabolismo , Proteínas Quinasas Activadas por Mitógenos , Metabolismo , Fosforilación , Leucemia-Linfoma Linfoblástico de Células Precursoras , Metabolismo , Inhibidores de Proteínas Quinasas , Farmacología , Piridinas , Farmacología , Transducción de Señal , Factor de Necrosis Tumoral alfa , MetabolismoRESUMEN
OBJECTIVE@#To observe the proliferation of SW480 cells exposed to different concentrations of CoCl2, and to examine the expression of hypoxiainducible factor-1 alpha (HIF-1alpha) and heme oxygenase-1 (HO-1) during hypoxia to explore the chemotherapy resistance effect and role of HIF-1alpha and HO-1.@*METHODS@#Methyl thiazolyl tetrazolium (MTF) method was used to detect the proliferation of SW480 cells in the presence of fluorouracil (FU). RT-PCR was applied to examine the expression of HIF-1alpha and HO-1 mRNA in hypoxia.@*RESULTS@#SW480 cells were proliferated at a slow rate, and had a strong resistance to FU with the increase of CoCl2. RT-PCR showed that the up-regulated expression of HIF-1alpha and HO-1 mRNA was consistent with the dose-effect curve and time-effect curve.@*CONCLUSION@#The hypoxia induced by CoCl2 can inhibit the proliferation of SW480, and it can also decrease the sensitivity of the cell to FU. The mechanism is probably related to the up-regulated expression of HIF-1alpha and HO-1 mRNA.
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Humanos , Antimutagênicos , Farmacología , Hipoxia de la Célula , Línea Celular Tumoral , Proliferación Celular , Cobalto , Farmacología , Neoplasias del Colon , Patología , Resistencia a Antineoplásicos , Fluorouracilo , Farmacología , Hemo-Oxigenasa 1 , Genética , Factor 1 Inducible por Hipoxia , Genética , ARN Mensajero , Genética , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
OBJECTIVE@#To investigate the killing effects of VP(3) on nasopharyngeal carcinoma cell line CNE-2.@*METHODS@#Plasmid expression vector pcDNA3.1(-) CMV.VP(3)-His was constructed and identified by Kpn I/EcoR I endonuclease analysis, and then sequenced to verify successful insertion in the sense direction of VP(3) gene. pcDNA3.1(-) CMV.VP(3)-His and pcDNA3.1(-)-His expression plasmid was transiently transfected into nasopharyngeal carcinoma cell line CNE-2 . VP(3) protein expression was detected by Western blotting. MTT assay was used to determine the killing effects of VP(3) gene on nasopharyngeal carcinoma cell line CNE-2.@*RESULTS@#Endonuclease analysis and sequencing confirmed the recombinant plasmid contained the complete VP(3) CDS sequence. Western blotting detected a 14.03 kD protein expression from the transfected cells, which was the expecting band of VP(3) gene. The growth of CNE-2 cells that expressed VP(3) gene was inhibited,while the growth of CNE-2 cells that did not express VP(3) gene was not inhibited.@*CONCLUSION@#VP(3) gene can kill nasopharyngeal carcinoma cell CNE-2.
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Humanos , Antineoplásicos , Farmacología , Secuencia de Bases , Proteínas de la Cápside , Genética , Fisiología , Línea Celular Tumoral , Terapia Genética , Datos de Secuencia Molecular , Neoplasias Nasofaríngeas , Patología , TransfecciónRESUMEN
OBJECTIVE@#To explore the protective effect of HSP72 on the acute injury of cardiomyocyte induced by oxidative stress.@*METHODS@#Cardiomyocytes of neonatal rats treated with heat shock (42 degrees C, 30 min, recovery for 6 h) to induce the expression of HSP72 and HSP72 antisense oligonucleotide was transformed to block the expression of HSP72. 0.5 mmol/L (final concentration) H2O2 was added into the culture medium to mimic oxidative stress, and to induce the acute injury of neonatal cardiomyocytes. The release of LDH and the total protein synthesis were applied to evaluate the injury of cardiomyocyte of neonatal rats.@*RESULTS@#Oxidative stress could significantly increase the release of LDH, and inhibit the total protein synthesis. By inducing the expression of HSPs, heat shock pretreatment significantly reduced the release of LDH and relieved the oxidative stress-mediated inhibition of total protein synthesis. Moreover, HSP7-2 anti-sense oligonucleotide could remarkably block the protective effect of heat shock pretreatment on the cellular injuries induced by H2O2.@*CONCLUSION@#HSP72 plays a most important role in the acute injury of cardiomyocyte mediated by oxidative stress.
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Animales , Ratas , Animales Recién Nacidos , Células Cultivadas , Proteínas del Choque Térmico HSP72 , Farmacología , L-Lactato Deshidrogenasa , Metabolismo , Miocitos Cardíacos , Patología , Oligonucleótidos Antisentido , Farmacología , Estrés Oxidativo , Biosíntesis de Proteínas , Distribución Aleatoria , Ratas WistarRESUMEN
OBJECTIVE@#To observe the effect of heat shock factor 1 (HSF1) on heat stress-induced apoptosis in Raw264.7 macrophages.@*METHODS@#Raw264.7 cells transfected with pcDNA3.1 and pcDNA3.1-HSF1 were exposed to heat stress (42.5 degrees C +/- 0.5 degrees C) for 1 h and recovered at 37 degrees C for 6, 9, 12, and 24 h respectively. Flow cytometry (FCM), Hoechst 33258 staining and DNA ladder assays were performed to assess the apoptosis.@*RESULTS@#After heat stress, FCM showed that apoptotic cells were increased significantly and reached the peak at 9 h in Raw 264.7 cells transfected with pcDNA3.1, and were characterized with classical morphologic changes including apoptotic body and nuclear condensation. Agarose gel electrophoresis showed that "DNA ladder" could be observed clearly at 6, 9, and 12 h after the heat stress. But the overexpression of HSF1 could reduce the number of apoptotic cells and inhibit DNA fragmentation.@*CONCLUSION@#HSF1 can inhibit heat stress-induced apoptosis in Raw264.7 macrophages.
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Animales , Ratones , Ratas , Apoptosis , Células Cultivadas , Proteínas de Unión al ADN , Farmacología , Factores de Transcripción del Choque Térmico , Respuesta al Choque Térmico , Macrófagos , Biología Celular , Factores de Transcripción , Farmacología , TransfecciónRESUMEN
OBJECTIVE@#To establish immortalized embryonic fibroblast lines in heat shock transcription factor 1 (HSF1) HSF1-/- and HSF1+/+ mice and to provide experimental models to study the function of HSF1.@*METHODS@#A mammalian expression vector (pSV3neo) containing the SV40 large T antigen was used to transfect the HSF1-/- and HSF1+/+ mouse embryonic fibroblast using Lipofectamine 2000. Colonies were screened by G418 and expanded to immortalized cell lines. PCR was used to detect the integration of the large T antigen with genome in the mouse embryonic fibroblast. Expression of SV40 large T antigen gene in expanded cells was identified by RT-PCR. HSP70 expression was examined by Western blot in the embryonic fibroblast lines.@*RESULTS@#The stable growth and serial propagation were observed in the HSF1-/- and HSF1+/+ cell lines for six months. The mRNA of SV40 T antigen gene expressed in the two cell lines. HSP70 expression could not be induced in the heat-treated HSF1-/- mouse embryo fibroblasts.@*CONCLUSION@#The immortalized cells of HSF1+/+ and HSF1-/- mouse embryo fibroblasts are successfully established.
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Animales , Femenino , Masculino , Ratones , Antígenos Transformadores de Poliomavirus , Farmacología , Línea Celular , Proteínas de Unión al ADN , Genética , Embrión de Mamíferos , Fibroblastos , Biología Celular , Factores de Transcripción del Choque Térmico , Ratones Noqueados , Factores de Transcripción , GenéticaRESUMEN
OBJECTIVE@#To screen the inflammatory mediators genes regulated by HSF1, and explore the mechanism of downstream genes regulated by HSF1.@*METHODS@#HSF-/- and HSF1+/+ mice were injected with 15 mg/kg LPS intraperitoneally (ip), respectively, and were treated as previous after HSR. The total RNA of lung tissues were extracted and filtrated by SuperArray gene Microarry. The promoter of candidate genes were analyzed by transcription element search software to search for heat shock element (HSE). Select the suppressor of cytokine signaling 3 (SOCS3) with HSE. Macrophage cells were stimulated with 400 ng/mL LPS, and were treated as previous after HSR, then the total RNA was extracted respectively. RT-PCR and northern blot assay were performed to detect the expression levels of SOCS3 mRNA.@*RESULTS@#Fifteen genes were repressed by HSF1, including 9 genes with complete HSE. Eleven genes were accelerated by HSF1 possibly, including 8 genes with complete HSE. The promoter of SOCS3 gene contained one complete HSE. LPS stimulation obviously increased the levels of SOCS3 mRNA in macrophages of RAW264.7 mice, which was inhibited by HSR and over-expression of HSF1.@*CONCLUSION@#HSR or HSF1 inhibits LPS induced expression of SOCS3 mRNA; HSF1 might inhibit LPS-induced expression of SOCS3 mRNA by binding to HSE in the promoter of SOCS3 gene.
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Animales , Ratones , Proteínas de Unión al ADN , Genética , Farmacología , Endotoxemia , Genética , Factores de Transcripción del Choque Térmico , Proteínas de Choque Térmico , Genética , Inflamación , Genética , Lipopolisacáridos , Macrófagos , Metabolismo , Ratones Endogámicos BALB C , Ratones Noqueados , Mutación , ARN Mensajero , Genética , Transducción de Señal , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas , Genética , Factores de Transcripción , Genética , FarmacologíaRESUMEN
OBJECTIVE@#To observe whether HSP70 could protect against H2O2-induced apoptosis in C2C12 myogenic cells by inhibiting Smac release from the mitochondria.@*METHODS@#HSP70 gene and full length Smac gene was transiently transfected in C2C12 myogenic cells by lipofectamine and the protein levels of HSP70 and Smac were analysed by Western blotting. Hoechst 33 258 staining was used to examine cell morphological changes and to calculate percentage of apoptotic nuclei. DNA ladder pattern on agarose gel electrophoresis was used to observe the DNA fragmentation. Activities of caspase-3 and caspase-9 were assayed with Western blotting. The release of Smac from the mitochondria to the cytoplasm was observed by immunofluorescence.@*RESULTS@#H2O2 ( 0.5 mmol/L ) activated caspase-3, caspase-9 8 h after the treatment and specific morphological changes of apoptosis 12 h after the treatment, and overexpression of Smac significantly promoted H2O2-induced activation of caspase-3, caspase-9 and apoptosis in C2C12 myogenic cells. HSP70 overexpression significantly inhibited H2O2-induced and Smac-promoted apoptosis, as shown by no specific DNA ladder pattern in agarose gel electrophoresis, decrease of percentage of apoptotic nuclei, and marked inactivation of caspase-3 and caspase-9. HSP70 could inhibit the release of Smac from the mitochondria to the cytoplasm 2 h after the treatment by H2O2.@*CONCLUSION@#HSP70 inhibits Smac release from the mitochondria and protects against H2O2-induced apoptosis in C2C12 myogenic cells.
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Humanos , Apoptosis , Proteínas Reguladoras de la Apoptosis , Células Cultivadas , Proteínas HSP70 de Choque Térmico , Farmacología , Peróxido de Hidrógeno , Péptidos y Proteínas de Señalización Intracelular , Metabolismo , Mitocondrias Cardíacas , Metabolismo , Proteínas Mitocondriales , Metabolismo , Mioblastos , Metabolismo , Miocitos Cardíacos , MetabolismoRESUMEN
OBJECTIVE@#To investigate the effect of oxidative stress on the accumulation of heat shock protein 70 (HSP70) within C2C12 myogenic cells.@*METHODS@#Heat shock response (42 degrees C for 1 h and recovery for 12 h at 37 degrees C) was used to induce the expression of heat shock protein 70. We constructed a recombinant plasmid of HSP70 with enhanced green fluorescent protein (EGFP). After being transfected transiently into C2C12 cells, immunoblotting was used to detect the expression of HSP70 induced by heat shock response and transfection. Immunocytochemistry, fluorescent microscopy and immunoblotting were used to detect the translocation of HSP70.@*RESULTS@#Immunoblotting showed that the overexpression of HSP70 was induced by heat shock response and transient transfenction. HSP70 localized within the cytoplasm of the normal cells, but HSP70 translocated from the cytoplasm to the nucleus and the nucleolus at 1 h after the treatment of oxidative stress (0.5 mmol/L H2O2) by using immunocytochemistry, fluorescent microscopy and immunoblotting for cellular partial proteins.@*CONCLUSION@#Oxidative stress may induce the accumulation of heat shock protein 70 within the nucleolus.
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Humanos , Nucléolo Celular , Metabolismo , Células Cultivadas , Proteínas HSP70 de Choque Térmico , Metabolismo , Mioblastos , Biología Celular , Metabolismo , Miocitos Cardíacos , Biología Celular , Metabolismo , Estrés Oxidativo , FisiologíaRESUMEN
OBJECTIVE@#To clarify the effect of nucleolin on the proliferation and apoptosis in C2C12 cells.@*METHODS@#After inhibiting the expression of nucleolin using antisense oligonucleotides, the cellular proliferation was determined by MTT, and the apoptosis was detected by flow cytometry (FCM) assays and DNA ladder assays.@*RESULTS@#After being transfected with antisense oligonucleotides for 24 hours, Western blotting showed that the expression of nucleolin was repressed significantly. In cells treated with antisense oligonucleotides, the cellular proliferation was obviously inhibited; the apoptotic cell increased significantly; and the "DNA ladder" was clearly observed. But the sense and random oligonucleotides had no effect on the cellular proliferation and apoptosis.@*CONCLUSION@#The down-regulation of nucleolin can inhibit the cellular proliferation and initiate the apoptosis in C2C12cells.
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Animales , Ratones , Apoptosis , Fisiología , Proliferación Celular , Células Cultivadas , Regulación hacia Abajo , Mioblastos , Biología Celular , Miocitos Cardíacos , Biología Celular , Oligonucleótidos Antisentido , Fosfoproteínas , Genética , Proteínas de Unión al ARN , Genética , TransfecciónRESUMEN
OBJECTIVE@#To determine the characteristics of a novel gene Mip5 (GenBank accession number AY553870) and its expression under physiological and pathological conditions.@*METHODS@#The characteristics of Mip5 were analyzed by bioinformatic programs including BLAST, spidey, psort, ClustalW and so on. RT-PCR was performed to detect Mip5 expression.@*RESULTS@#Bioinformatic analysis showed that Mip5 gene lied in the 13th chromosome and contained 8 exons and 7 introns, its open reading frame contained 909 bp and its protein production was 302 amino acid residues including 6 kelth domains. Under normal conditions, MIP5 expressed abundantly in the heart, brain and kidney, but its expression could not be detected in the liver and muscle. Expression of Mip5 gene was increased significantly after ischemia-reperfusion compared with the sham groups, and reached its peak at 3 h and recovered at 12 h after the reperfusion. Conclusion Mip5 gene is a novel gene containing a putative open reading frame of 302 amino acids residues and may play an important role in rat cardiomyocytes suffering ischemia processing.
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Animales , Humanos , Masculino , Ratas , Secuencia de Aminoácidos , Secuencia de Bases , Cromosomas Humanos Par 13 , Genética , ADN Complementario , Genética , Datos de Secuencia Molecular , Isquemia Miocárdica , Genética , Daño por Reperfusión Miocárdica , Genética , Sistemas de Lectura Abierta , GenéticaRESUMEN
Objective To examine the expression of toll-like receptor 2(TLR2)in peripheral blood monocytes and explore its association with disease stages and clinical manifestations and to explore the patho- genesis of rheumatoid arthritis(RA).Methods The expression of toll-like receptor 2 in peripheral blood monocytes from 47 RA patientis(27 in active stage and 20 in stable stage)and 18 normal individuals were de- tected by flowcytometry and RT-PCR.Results The expression of toll-like receptor 2 in peripheral blood monocytes in patients with active disease was significantly increased compared to non-active patients and nor- mal individuals,The expression was found to correlate with the Disease Active Score(DAS),serum C-reactive protein(CRP)level and the erythrocyte sedimentation rate(ESR),but not correlate with rheumatoid factor (RF)and the anti-cyclic citrullinated peptide(CCP)antibody.Conclusion The expression of toll-like recep- tor 2 in peripheral blood monocytes of patients with active RA is significantly increased.And the expression is correlated with disease activity index.The innate immune system is activated in patients with active disease. And the increased expression may promote the activities of monocytes.
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Objective To demonstrate high mobility group box chromosomal protein 1(HMGBI) expression in synovium and joint,and to identify the role of HMGB1 in the pathogenesis of synovitis and joint destruction in adjuvant-induced arthritis(AA).Methods AA of 15 male rats were induced in SD rats by intradermal injection of 100?l Freud's complete adjuvant in the foot pad of the left hind paw.All rats were killed at the 18th day.Synovium and joints were collected for histopathology studies and determining the expression of HMGB1 by immunohistochemistry,and serum was collected for determining the expression of HMGB1 by western blotting analysis.Results Immunostaining of specimens from normal rats showed that HMGB1 was primarily confined to the nucleus of synoviocytes with occasional cytoplasmic staining.In contrast, inflammatory synovial tissues from AA rats showed a distinctly different HMGB1 staining pattern.Nuclear HMGBI expression was accompanied by a cytoplasmic staining in many mononuclear cells.The cytoplasmic HMGB1 expression in synovium of AA rats is significantly higher than that of normal rats.Additionally,HMGBI was highly expressed in the nuclei and cytoplasm of the subchondral chondrocytes and inflammatory cells in bone erosion in AA rats(P<0.01),while fewer positive cytoplasmic staining of HMGB1 was found in chondrocytes and fewer positive nuclear staining was found in bone cells in normal rats.HMGB1 concentration was significantly higher in serum of AA rats than that in normal rats(P<0.001).Conclusion The cytoplasmic HMGBI expression in synovium and joints is greatly upregulated;the level of HMGB1 in serum is increased in AA rats which suggests a patbogenetic role of HMGB1 in synovitis and bone destruction of adjuvant-induced arthritis.
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Objective To determine the effects of~(99)Tc-MDP on joint inflammation and bone destruc- tion in collagen-induced arthritis(CIA)rats model and its effect on tumor necrosis factor alpha(TNF-?). Methods CIA was induced by immunization of male SD rats with an emulsion of collagen.~(99)Tc-MDP or placebo was intravenous infused to rats for 20 days.Joint inflammation was assessed by arthritis index.Lesions of bone were assessed based on the histological changes in ankle joints,radiographic analysis in hind paw with Larsen score.Systemic TNF-?level was measured by radioimmune assay.Results~(99)Tc-MDP suppressed joint swelling(P