Perinatal complications,such as asphyxia,can cause brain injuries that are often associated with subsequent neurological deficits,such as cerebral palsy or mental retardation.The mechanisms of perinatal brain injury a...Perinatal complications,such as asphyxia,can cause brain injuries that are often associated with subsequent neurological deficits,such as cerebral palsy or mental retardation.The mechanisms of perinatal brain injury are not fully understood,but mitochondria play a prominent role not only due to their central function in metabolism but also because many proteins with apoptosis-related functions are located in the mitochondrion.Among these proteins,apoptosis-inducing factor has already been shown to be an important factor involved in neuronal cell death upon hypoxia-ischemia,but a better understanding of the mechanisms behind these processes is required for the development of more effective treatments during the early stages of perinatal brain injury.In this review,we focus on the molecular mechanisms of hypoxic-ischemic encephalopathy,specifically on the importance of apoptosis-inducing factor.The relevance of apoptosis-inducing factor is based not only because it participates in the caspase-independent apoptotic pathway but also because it plays a crucial role in mitochondrial energetic functionality,especially with regard to the maintenance of electron transport during oxidative phosphorylation and in oxidative stress,acting as a free radical scavenger.We also discuss all the different apoptosis-inducing factor isoforms discovered,focusing especially on apoptosis-inducing factor 2,which is only expressed in the brain and the functions of which are starting now to be clarified.Finally,we summarized the interaction of apoptosis-inducing factor with several proteins that are crucial for both apoptosis-inducing factor functions(prosurvival and pro-apoptotic)and that are highly important in order to develop promising therapeutic targets for improving outcomes after perinatal brain injury.展开更多
BACKGROUND: Previous studies have reported that statins are less toxic to the human body and have greater antitumor activity; however, few studies have addressed the antitumor effect of statins combined with tumor ne...BACKGROUND: Previous studies have reported that statins are less toxic to the human body and have greater antitumor activity; however, few studies have addressed the antitumor effect of statins combined with tumor necrosis factor-related apoptosis inducing ligand (TRAIL). OBJECTIVE: To explore the effect of TRAIL combined with mevastatin on the proliferation and apoptotic cell death of a human glioma cell line SWO-38, and to study its mechanism of action. DESIGN, TIME AND SETTING: An in vitro control experiment was performed at the Central Laboratory of the Third Hospital Affiliated to Sun Yat-sen University, between January and April 2009. MATERIALS: The human SWO-38 cell line was provided by Cell Research, Department of Animal Experimental Center of Sun Yat-sen University; human recombinant soluble TRAIL by R&D, USA; and mevastatin by Sigma, USA. METHODS: SWO-38 cells were separately incubated in TRAIL (100, 200, 300, 400, and 500 tJg/L) and mevastatin (5, 10, 20, 30, and 40 pmol/L) for 72 hours. In addition, SWO-38 cells were incubated in TRAIL (300 μg/L), mevastatin (30 μmol/L), and a solution containing both TRAIL and mevastatin for 12, 24, 48 and 72 hours. MAIN OUTCOME MEASURES: Cell proliferation was detected using methyl thiazolyl tetrazolium assay; cell apoptosis was observed using Hoechst 33258 staining and fluorescence microscopy and was measured using Annexin V/propidium iodide flow cytometry; TRAIL R1/DR4 and TRAIL R2/DR5 protein expressions levels were measured using indirect immunofluorescence staining combined with flow cytometry in the recombinant soluble TRAIL (rsTRAIL, 300 tJg/L), mevastatin (30 IJmol/L) and combination groups; TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression was detected using real-time polymerase chain reaction. RESULTS: rsTRAIL, mevastatin and their combination inhibited tumor proliferation in a time- and dose-dependent manner. The proliferation inhibitory rate and apoptosis rate of human SWO-38 cells in the combined group were significantly greater than the rsTRAIL or mevastatin alone group (P 〈 0.01). TRAIL R1/DR4 and TRAIL R2/DR5 protein and mRNA expressions were increased in the combination group compared with mevastatin or rsTRAIL alone after 72 hours (P 〈 0.01). CONCLUSION: Both rsTRAIL and mevastatin inhibit the proliferation and apoptosis of the human glioma cell line SWO-38, while their combination enhances the anti-tumor effect. The mechanism of action possibly correlates to the upregulation of TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression by mevastatin, thereby enhancing the cell sensitivity to rsTRAIL.展开更多
Studies have shown that tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)exhibits strong induction of apoptosis in human glioma cells.It remains unclear whether the mitochondrion pathway,an important ap...Studies have shown that tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)exhibits strong induction of apoptosis in human glioma cells.It remains unclear whether the mitochondrion pathway,an important apoptosis signaling pathway,is involved in TRAIL-induced glioma cell apoptosis.In the present study,in vitro cultured human glioma U87 cells were treated with human recombinant soluble TRAIL.Apoptosis of glioma U87 cells,mitochondrial transmembrane potential(Δψm),cytoplasmic cytochrome c concentration and changes in caspase-3,-8 and-9 activity following human recombinant soluble TRAIL treatment were investigated to determine the mechanism of glioma U87 cell apoptosis induced by TRAIL.Additionally,blocking caspase-8resulted in TRAIL-induced mitochondrion pathway activation,suggesting that TRAIL,through activating caspase-8,initiated a series of mitochondrial events and resulted in apoptosis of glioma U87 cells.展开更多
Most of the ocular tumors have poor prognosis, and they remain a difficult problem in the area of ophthalmology. With the rapid development of molecular biology and immunologic techniques and the deep research on ocul...Most of the ocular tumors have poor prognosis, and they remain a difficult problem in the area of ophthalmology. With the rapid development of molecular biology and immunologic techniques and the deep research on ocular tumor related genes, it becomes possible to diagnose and treat malignant tumors from the molecular level. The tumor necrosis factor related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor (TNF) super family, is a promising candidate, either alone or in combination with established cancer therapies, since it can initiate apoptosis through the activation of their death receptors. The ability of TRAIL to selectively induce apoptosis of transformed, virus-infected or tumor cells but not normal cells promotes the development of TRAIL-based cancer therapy. Here, we will review TRAIL and its receptors' structure, function, mechanism of action and application in ocular tumors therapy.展开更多
BACKGROUND: Receptors for tumor necrosis factor related apoptosis inducing ligand (TRAIL) include death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2. Activation of death receptor 4 and 5 sel...BACKGROUND: Receptors for tumor necrosis factor related apoptosis inducing ligand (TRAIL) include death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2. Activation of death receptor 4 and 5 selectively kills tumor cells. OBJECTIVE: To detect TRAIL receptor expression in glioblastoma by immunohistochemistry and RT-PCR, and to compare this expression to that in normal brain tissue. DESIGN: Observational analysis. SETTING: Department of Pathology, the First Affiliated Hospital of Zhengzhou University; Henan Tumor Pathology Key Laboratory. PARTICIPANTS: Twenty-five patients (17 males and 8 females) who received glioblastoma resection were selected from the Fifth Affiliated Hospital of Zhengzhou University, between September 2003 to June 2004. All glioblastoma samples were diagnosed pathologically. Twenty patients (12 males and 8 females) with craniocerebral injury who received normal brain tissue resection were selected in the same time period. There were no significant differences in sex and age between glioblastoma patients or between craniocerebral injury patients (P 〉 0.05). All patients and appropriate relatives provided informed consent, and this study was approved by the local research ethics committee. METHODS: Polyclonal antibody against TRAIL receptors and an immunohistochemical kit (batch number: 200502) were purchased from Boster Company, Wuhan. Immunohistochemistry: Expression of death receptor 4, death receptor 5, decoy receptor l, and decoy receptor 2 were observed in both glioblastoma and normal brain tissue. The experiment was performed according to the kit instructions, and positive staining was brown-yellow. Assessment: There were no positive signals (-); weakly positive signals, positive cells 〈 25% (+); weakly positive signals, positive cells 25%-50% (++); strongly positive signals, positive cells 50%-75% (+++); strongly positive signals, positive cells 〉 75% (++++). Evaluation: Expression levels of TRAIL receptors were estimated in both normal brain tissue and glioblastoma. Expression of decoy receptor 1 and decoy receptor 2 mRNA in glioblastoma were detected by reverse transcription polymerase chain reaction, and expression of decoy receptor in glioblastoma was estimated. MAIN OUTCOME MEASURES: Comparison of death receptor and decoy receptor protein expression between glioblastoma and normal brain tissue; decoy receptor mRNA expression in glioblastoma. RESULTS: Death receptor protein expression was strongly positive (+++) in glioblastoma, while it was weakly positive (+, ++) in normal brain tissue. Therefore, expression rate of death receptor protein in the glioblastoma was significantly higher than that in the normal brain tissue (.~ 2 = 18.48, 23.03, P 〈 0.01). Decoy receptor protein expression in the glioblastoma was significantly lower than that in the normal brain tissue ( x2 = 6.65, 18.76, P 〈 0.01). The level of decoy receptor mRNA expression in glioblastoma was significantly higher than those of protein expression ( x 2 = 9.82, 10.09, P〈 0.01). CONCLUSION: High expression of death receptor and low expression of decoy receptor are frequently observed in glioblastoma, suggesting that TRAIL receptor genes show an anti-tumor and expressive response during the initiation and development of the tumor. There are significant differences in decoy receptor expression between normal brain tissue and glioblastoma, suggesting that the restricted expression of decoy receptor in glioblastoma is regulated at the post-transcriptional level.展开更多
AIM: To investigate the potential of pigment epitheliumderived factor(PEDF) to protect the immortalized rat retinal ganglion cells-5(RGC-5) exposed to Co Cl2-induced chemical hypoxia. METHODS: After being differ...AIM: To investigate the potential of pigment epitheliumderived factor(PEDF) to protect the immortalized rat retinal ganglion cells-5(RGC-5) exposed to Co Cl2-induced chemical hypoxia. METHODS: After being differentiated with staurosporine(SS), RGC-5 cells were cultured in four conditions: control group cells cultured in Dulbecco 's modified eagle medium(DMEM) supplemented with 10% fetal bovine serum, 100 μmol/m L streptomycin and penicillin(named as normal conditions); hypoxia group cells cultured in DMEM containing 300 μmol/m L Co Cl2; cells in the group protected by PEDF were first pretreated with 100 ng/m L PEDF for 2h and then cultured in the same condition as hypoxia group cells; and PEDF group cells that were cultured in the presence of 100 ng/m L PEDF under normal conditions. The cell viability was assessed by MTT assay, the percentage of apoptotic cells was quantified using Annexin V-FITC apoptosis kit, and intra-cellar reactive oxygen species(ROS) was measured by dichloro-dihydro-fluorescein diacetate(DCFH-DA) probe. The mitochondria-mediated apoptosis was also examined to further study the underlying mechanism of the protective effect of PEDF. The opening of mitochondrial permeability transition pores(m PTPs) and membrane potential(Δψm) were tested as cellular adenosine triphosphate(ATP) level and glutathione(GSH). Also, the expression and distribution of Cyt C and apoptosis inducing factor(AIF) were observed.RESULTS: SS induced differentiation of RGC-5 cells resulting in elongation of their neurites and establishing contacts between outgrowths. Exposure to 300 μmol/m L Co Cl2 triggered death of 30% of the total cells in cultures within 24 h. At the same time, pretreatment with 100 ng/m L PEDF significantly suppressed the cell death induced by hypoxia(P〈0.05). The apoptosis induced by treatment of Co Cl2 was that induced cell death accompanied with increasing intracellar ROS and decreasing GSH and ATP level. PEDF pretreatment suppressed these effects(P〈0.05). Additionally, PEDF treatment inhibited the opening of m PTPs and suppressed decreasing of Δψm in RGC-5 cells, resulting in blocking of the mitochondrial apoptotic pathway.CONCLUSION: Pretreatment of RGC-5 cells with 100 ng/m L PEDF significantly decreases the extent of apoptosis. PEDF inhibits the opening of m PTPs and suppresses decreasing of Δψm. Moreover, PEDF also reduces ROS production and inhibits cellular ATP level's reduction. Cyt C and AIF activation in PEDF-pretreated cultures are also reduced. These results demonstrate the potential for PEDF to protect RGCs against hypoxic damage in vitro by preventing mitochondrial dysfunction.展开更多
BACKGROUND: Recent studies have demonstrated that tumor necrosis factor-like weak inducer of apoptosis (TWEAK) participates in brain edema. However, it is unclear whether blood-brain barrier (BBB) disruption is a...BACKGROUND: Recent studies have demonstrated that tumor necrosis factor-like weak inducer of apoptosis (TWEAK) participates in brain edema. However, it is unclear whether blood-brain barrier (BBB) disruption is associated with TWEAK during the process of brain edema OBJECTIVE: To investigate the effects of TWEAK on BBB permeability in brain edema. DESIGN, TIME AND SETTING: An immunohistochemical observation, randomized, controlled animal experiment was performed at the Laboratory of Neurosurgical Anatomy, Xiangya Medical College, Central South University & Central Laboratory, Third Xiangya Hospital, Central South University between January 2006 and December 2007. MATERIALS: A total of 48 adult Wistar rats were randomly divided into three groups: normal control (n = 8), sham-operated (n = 8), and ischemia/reperfusion (n = 32). Rats from the ischemia/reperfusion group were randomly assigned to four subgroups according to different time points, i.e., 2 hours of ischemia followed by 6 hours (n = 8), 12 hours (n = 8), 1 day (n = 8), or 12 days (n = 8) of reperfusion. METHODS: Focal cerebral ischemia/reperfusion injury was induced by middle cerebral artery occlusion (MCAO) using the suture method in rats from the ischemia/reperfusion group. Thread was introduced at a depth of 17-19 mm. Rats in the sham-operated group were subjected to experimental procedures similar to the ischemia/reperfusion group; however, the introducing depth of thread was 10 mm. The normal control group was not given any intervention. MAIN OUTCOME MEASURES: TWEAK expression was examined by immunohistochemistry; brain water content on the ischemic side was calculated as the ratio of dry to wet tissue weight; BBB permeability was measured by Evans blue extravasation. RESULTS: A total of eight rats died prior to and after surgery and an additional eight rats were randomly entered into the study. Thus 48 rats were included in the final analysis. In the ischemia/reperfusion group, TWEAK-positive cells were present in the ischemic penumbra surrounding the lamellar necrotic region in the fight cerebral hemisphere at 6 hours reperfusion and increased thereafter; by 2 days reperfusion they had reached a peak level, which was significantly higher than the sham-operated and normal control groups (P 〈 0.05). At 6 hours reperfusion, both brain water content and Evans blue extravasation showed the same tendency for change as TWEAK expression. Pearson correlation analysis results revealed that the degree of TWEAK expression was positively correlated with brain water content (r = 0.892, P 〈 0.05). CONCLUSION: The present results confirmed that TWEAK was involved in BBB disruption and participated in brain edema following cerebral ischemia.展开更多
Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2'-disulfonic ...Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid. Results showed that the survival rate of neurons was significantly increased after treatment with 4,4-diisothiocyanatostilbene-2,2'-disulfonic acid, and the rate of apoptosis decreased. In addition, the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor were significantly reduced. Our experimental findings indicate that the chloride channel blocker 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid can antagonize apoptotic cell death of hippocampal neurons by inhibiting the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor.展开更多
Objective To study the effect of γ-interferon (IFNγ), tumor necrosis factor related apoptosis inducing ligand (TRAIL), and cisplatin or etoposide induced apoptosis in human neuroblastoma cell line SH-SY5Y and its po...Objective To study the effect of γ-interferon (IFNγ), tumor necrosis factor related apoptosis inducing ligand (TRAIL), and cisplatin or etoposide induced apoptosis in human neuroblastoma cell line SH-SY5Y and its possible molecular mechanisms.Methods The expressions of Caspase 8 mRNA and protein were detected with RT-PCR and Western blot analysis. The effects of IFNγ, TRAIL, IFNγ+TRAIL, IFNγ+Caspase 8 inhibitor+TRAIL, IFNγ+cisplatin+TRAIL, and IFNγ+etoposide+TRAIL on the growth and apoptosis of SH-SY5Y cells were detected with the methods of MTT and flow cytometry. The relative Caspase 8 activity was measured with colorimetric assay. Results Caspase 8 was undetectable in SH-SY5Y cells but an increased expression of Caspase 8 mRNA and protein was found after treatment with IFNγ. SH-SY5Y cells themselves were not sensitive to TRAIL, but those expressing Caspase 8 after treatment with IFNγ were. The killing effect of TRAIL on SH-SY5Y cells expressing Caspase 8 was depressed by Caspase 8 inhibitor. Cisplatin and etoposide could enhance the sensitivity of TRAIL on SH-SY5Y cells. The relative Caspase 8 activity of SH-SY5Y cells in IFNγ+TRAIL group was significantly higher than those of control group, IFNγ group, TRAIL group, and inhibitor group (P<0.01). There was no significant difference among IFNγ+TRAIL group, IFNγ+cisplatin+TRAIL group, and IFNγ+etoposide+TRAIL group.Conclusions IFNγ could sensitize SH-SY5Y cells to TRAIL-induced apoptosis and this may be realized by the upregulation of Caspase 8. Cisplatin and etoposide could enhance the killing effect of TRAIL on SH-SY5Y cells.展开更多
Apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) can be regulated by the epidermal growth factor(EGF) signaling pathway.In this study,recombinant adenoviral vectors that encode TRAIL...Apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) can be regulated by the epidermal growth factor(EGF) signaling pathway.In this study,recombinant adenoviral vectors that encode TRAIL gene from the hTERT/RGD promoter(AdTRAIL) was combined with drugs including gefitinib,elotinib,and cetuximab that inhibit EGFR and the EGF signaling pathway in non-small cell lung cancer(NSCLC) cell lines to investigate their antitumor activity.In vitro,compared to single reagent,AdTRAIL combined with EGFR inhibitors reduced proliferation and enhanced apoptosis in H460,A549,and SW1573 cell lines.Western blot results suggested that these effects were relative to up-regulation of pro-apoptosis protein BAX and down-regulation of p-AKT.In vivo,AdTRAIL combined with cetuximab resulted in a significant growth reduction in H460 xenografts without damage to the main organs of nude mice.Histological examination and TUNEL analyses of xenografts showed that cetuximab enhanced cell apoptosis induced by AdTRAIL.These results indicate that EGFR inhibitors enhanced AdTRAIL anti-tumor activity in NSCLC cell lines and that inhibiting the AKT pathway played an important role in this enhancement.展开更多
AIM:To analyze the effect of chemotherapeutic drugs and specific kinase inhibitors,in combination with the death receptor ligand tumor necrosis factor-related apoptosis inducing ligand(TRAIL),on overcoming TRAIL resis...AIM:To analyze the effect of chemotherapeutic drugs and specific kinase inhibitors,in combination with the death receptor ligand tumor necrosis factor-related apoptosis inducing ligand(TRAIL),on overcoming TRAIL resistance in hepatocellular carcinoma(HCC)and to study the efficacy of agonistic TRAIL antibodies,as well as the commitment of antiapoptotic BCL-2 proteins, in TRAIL-induced apoptosis. METHODS:Surface expression of TRAIL receptors (TRAIL-R1-4)and expression levels of the antiapoptotic BCL-2 proteins MCL-1 and BCL-xL were analyzed by flow cytometry and Western blotting,respectively. Knock-down of MCL-1 and BCL-xL was performed by transfecting specific small interfering RNAs.HCC cellswere treated with kinase inhibitors and chemotherapeutic drugs.Apoptosis induction and cell viability were analyzed via flow cytometry and 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. RESULTS:TRAIL-R1 and-R2 were profoundly expressed on the HCC cell lines Huh7 and Hep-G2. However,treatment of Huh7 and Hep-G2 with TRAIL and agonistic antibodies only induced minor apoptosis rates.Apoptosis resistance towards TRAIL could be considerably reduced by adding the chemotherapeutic drugs 5-fluorouracil and doxorubicin as well as the kinase inhibitors LY294002[inhibition of phosphoinositol- 3-kinase(PI3K)],AG1478(epidermal growth factor receptor kinase),PD98059(MEK1),rapamycin(mam- malian target of rapamycin)and the multi-kinase inhibitor Sorafenib.Furthermore,the antiapoptotic BCL-2 proteins MCL-1 and BCL-xL play a major role in TRAIL resistance:knock-down by RNA interference increased TRAIL-induced apoptosis of HCC cells.Additionally, knock-down of MCL-1 and BCL-xL led to a significant sensitization of HCC cells towards inhibition of both c-Jun N-terminal kinase and PI3K.CONCLUSION:Our data identify the blockage of survival kinases,combination with chemotherapeutic drugs and targeting of antiapoptotic BCL-2 proteins as promising ways to overcome TRAIL resistance in HCC.展开更多
Recent studies have demonstrated that Notch-1 expression is increased in the hippocampus of Alzheimer's disease patients. We speculate that Notch-1 signaling may be involved in PC12 cell apoptosis induced by amyloid ...Recent studies have demonstrated that Notch-1 expression is increased in the hippocampus of Alzheimer's disease patients. We speculate that Notch-1 signaling may be involved in PC12 cell apoptosis induced by amyloid beta-peptide (25-35) (Aβ25-35). In the present study, PC12 cells were cultured with different doses (0, 0.1, 1.0, 10 and 100 nmol/L) of N-[N-(3,5-Difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester, a Notch-1 signaling pathway inhibitor, for 30 minutes. Then cultured cells were induced with Aβ25-3s for 48 hours. Pretreatment of PC12 cells with high doses of N-[N-(3,5-Difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (〉 10 nmol/L) prolonged the survival of PC12 cells after Aβ25-35 induction, decreased the expression of apoptosis-related proteins caspase-3, -8, -9, increased the activity of oxidative stress-related superoxide dismutase and catalase, inhibited the production of active oxygen, and reduced nuclear factor kappa B expression. This study indicates that the Notch-1 signaling pathway plays a pivotal role in Aβ25-35-induced PC12 apoptosis.展开更多
Studies have demonstrated that DL-3-n-butylphthalide can significantly alleviate oxygen glucose deprivation-induced injury of human umbilical vein endothelial cells at least partly associated with its enhancement on o...Studies have demonstrated that DL-3-n-butylphthalide can significantly alleviate oxygen glucose deprivation-induced injury of human umbilical vein endothelial cells at least partly associated with its enhancement on oxygen glucose deprivation-induced hypoxia inducible factor-1α expression.In this study,we hypothesized that DL-3-n-butylphthalide can protect against oxygen glucose deprivation-induced injury of newborn rat brain microvascular endothelial cells by means of upregulating hypoxia inducible factor-1α expression.MTT assay and Hoechst staining results showed that DL-3-n-butylphthalide protected brain microvascular endothelial cells against oxygen glucose deprivation-induced injury in a dose-dependent manner.Western blot and immunofluorescent staining results further confirmed that the protective effect was related to upregulation of hypoxia inducible factor-1α.Real-time RT-PCR reaction results showed that DL-3-n-butylphthalide reduced apoptosis by inhibiting downregulation of pro-apoptotic gene caspase-3 mRNA expression and upregulation of apoptosis-executive protease bcl-2 mRNA expression;however,DL-3-n-butylphthalide had no protective effects on brain microvascular endothelial cells after knockdown of hypoxia inducible factor-1α by small interfering RNA.These findings suggest that DL-3-n-butylphthalide can protect brain microvascular endothelial cells against oxygen glucose deprivation-induced injury by upregulating bcl-2 expression and downregulating caspase-3 expression though hypoxia inducible factor-1α pathway.展开更多
The expression of hypoxia inducible factor-1 alpha (HIF-1α) and its relationship to apoptosis in tissues around cerebral bleeding loci was studied. The expression of HIF-1α and apoptosis in 37 samples of tissues aro...The expression of hypoxia inducible factor-1 alpha (HIF-1α) and its relationship to apoptosis in tissues around cerebral bleeding loci was studied. The expression of HIF-1α and apoptosis in 37 samples of tissues around cerebral bleeding loci and 9 samples of normal cerebral tissues was assessed by immunohistochemical straining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling methods. In 37 tissue samples around cerebral bleeding loci, the positive rate of the HIF-1α expression was 40.6 %. Especially in the patients with amount of bleeding>60 ml, the positive rate (88.9 %) of the HIF-1α expression was significantly higher than those with the amount of bleeding ranging from 30—45 ml or 45—60 ml (P<0.05). The expression of HIF-1α was increased as the amount of bleeding and operative time increased (P<0.05). There existed a positive correlation between HIF-1α labeling index and apoptosis index (n=12, r=0.56, P<0.01). These results suggested that the expression of HIF-1α was closely related with the time of hemorrhage and the amount of bleeding, and could induce the apoptosis of neurons.展开更多
Hypoxiainducible factor1 and its specific target gene heme oxygenase1, are involved in acute cerebral ischemia. However, very few studies have examined in detail the changes in the hy poxiainducible factor1/heme oxyge...Hypoxiainducible factor1 and its specific target gene heme oxygenase1, are involved in acute cerebral ischemia. However, very few studies have examined in detail the changes in the hy poxiainducible factor1/heme oxygenase1 signaling pathway in chronic cerebral ischemia. In this study, a rat model of chronic cerebral ischemia was established by permanent bilateral common carotid artery occlusion, and these rats were treated with intragastric cilostazol (30 mg/kg) for 9 weeks. Morris water maze results showed that cognitive impairment gradually worsened as the cerebral ischemia proceeded. Immunohistochemistry, semiquantitative PCR and western blot analysis showed that hypoxiainducible factorla and heme oxygenase1 expression levels in creased after chronic cerebral ischemia, with hypoxiainducible factorla expression peaking at 3 weeks and heme oxygenase1 expression peaking at 6 weeks. These results suggest that the elevated levels of hypoxiainducible factorla may upregulate heine oxygenase1 expression fol lowing chronic cerebral ischemia and that the hypoxiainducible factor1/heme oxygenase1 sig naling pathway is involved in the development of cognitive impairment induced by chronic cerebral ischemia. Cilostazol treatment alleviated the cognitive impairment in rats with chronic cerebral ischemia, decreased hypoxiainducible factorla and heme oxygenase1 expression levels, and reduced apoptosis in the frontal cortex. These findings demonstrate that cilostazol can protect against cognitive impairment induced by chronic cerebral ischemic injury through an antiapoptotic mechanism.展开更多
基金the Swedish Research Council(2018-02667)the National Natural Science Foundation of China(31761133015,U1704281,81901335)+3 种基金the Swedish Childhood Cancer Foundation(PR2018-0082)Swedish Governmental Grants to Scientists Working in Health Care(ALFGBG-717791)the Swedish Brain Foundation(FO2018-0034)the Chinese Scholarship Council to TL(201707040025)and to YX(201507040082)。
文摘Perinatal complications,such as asphyxia,can cause brain injuries that are often associated with subsequent neurological deficits,such as cerebral palsy or mental retardation.The mechanisms of perinatal brain injury are not fully understood,but mitochondria play a prominent role not only due to their central function in metabolism but also because many proteins with apoptosis-related functions are located in the mitochondrion.Among these proteins,apoptosis-inducing factor has already been shown to be an important factor involved in neuronal cell death upon hypoxia-ischemia,but a better understanding of the mechanisms behind these processes is required for the development of more effective treatments during the early stages of perinatal brain injury.In this review,we focus on the molecular mechanisms of hypoxic-ischemic encephalopathy,specifically on the importance of apoptosis-inducing factor.The relevance of apoptosis-inducing factor is based not only because it participates in the caspase-independent apoptotic pathway but also because it plays a crucial role in mitochondrial energetic functionality,especially with regard to the maintenance of electron transport during oxidative phosphorylation and in oxidative stress,acting as a free radical scavenger.We also discuss all the different apoptosis-inducing factor isoforms discovered,focusing especially on apoptosis-inducing factor 2,which is only expressed in the brain and the functions of which are starting now to be clarified.Finally,we summarized the interaction of apoptosis-inducing factor with several proteins that are crucial for both apoptosis-inducing factor functions(prosurvival and pro-apoptotic)and that are highly important in order to develop promising therapeutic targets for improving outcomes after perinatal brain injury.
基金the National Natural Science Foundation of China, No. 30772537
文摘BACKGROUND: Previous studies have reported that statins are less toxic to the human body and have greater antitumor activity; however, few studies have addressed the antitumor effect of statins combined with tumor necrosis factor-related apoptosis inducing ligand (TRAIL). OBJECTIVE: To explore the effect of TRAIL combined with mevastatin on the proliferation and apoptotic cell death of a human glioma cell line SWO-38, and to study its mechanism of action. DESIGN, TIME AND SETTING: An in vitro control experiment was performed at the Central Laboratory of the Third Hospital Affiliated to Sun Yat-sen University, between January and April 2009. MATERIALS: The human SWO-38 cell line was provided by Cell Research, Department of Animal Experimental Center of Sun Yat-sen University; human recombinant soluble TRAIL by R&D, USA; and mevastatin by Sigma, USA. METHODS: SWO-38 cells were separately incubated in TRAIL (100, 200, 300, 400, and 500 tJg/L) and mevastatin (5, 10, 20, 30, and 40 pmol/L) for 72 hours. In addition, SWO-38 cells were incubated in TRAIL (300 μg/L), mevastatin (30 μmol/L), and a solution containing both TRAIL and mevastatin for 12, 24, 48 and 72 hours. MAIN OUTCOME MEASURES: Cell proliferation was detected using methyl thiazolyl tetrazolium assay; cell apoptosis was observed using Hoechst 33258 staining and fluorescence microscopy and was measured using Annexin V/propidium iodide flow cytometry; TRAIL R1/DR4 and TRAIL R2/DR5 protein expressions levels were measured using indirect immunofluorescence staining combined with flow cytometry in the recombinant soluble TRAIL (rsTRAIL, 300 tJg/L), mevastatin (30 IJmol/L) and combination groups; TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression was detected using real-time polymerase chain reaction. RESULTS: rsTRAIL, mevastatin and their combination inhibited tumor proliferation in a time- and dose-dependent manner. The proliferation inhibitory rate and apoptosis rate of human SWO-38 cells in the combined group were significantly greater than the rsTRAIL or mevastatin alone group (P 〈 0.01). TRAIL R1/DR4 and TRAIL R2/DR5 protein and mRNA expressions were increased in the combination group compared with mevastatin or rsTRAIL alone after 72 hours (P 〈 0.01). CONCLUSION: Both rsTRAIL and mevastatin inhibit the proliferation and apoptosis of the human glioma cell line SWO-38, while their combination enhances the anti-tumor effect. The mechanism of action possibly correlates to the upregulation of TRAIL R1/DR4 and TRAIL R2/DR5 mRNA expression by mevastatin, thereby enhancing the cell sensitivity to rsTRAIL.
基金the National Natural Science Foundation of China, No. 30672409the Science and Technology Foundation Program of Guangdong Province, No. 2006B36003017
文摘Studies have shown that tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)exhibits strong induction of apoptosis in human glioma cells.It remains unclear whether the mitochondrion pathway,an important apoptosis signaling pathway,is involved in TRAIL-induced glioma cell apoptosis.In the present study,in vitro cultured human glioma U87 cells were treated with human recombinant soluble TRAIL.Apoptosis of glioma U87 cells,mitochondrial transmembrane potential(Δψm),cytoplasmic cytochrome c concentration and changes in caspase-3,-8 and-9 activity following human recombinant soluble TRAIL treatment were investigated to determine the mechanism of glioma U87 cell apoptosis induced by TRAIL.Additionally,blocking caspase-8resulted in TRAIL-induced mitochondrion pathway activation,suggesting that TRAIL,through activating caspase-8,initiated a series of mitochondrial events and resulted in apoptosis of glioma U87 cells.
文摘Most of the ocular tumors have poor prognosis, and they remain a difficult problem in the area of ophthalmology. With the rapid development of molecular biology and immunologic techniques and the deep research on ocular tumor related genes, it becomes possible to diagnose and treat malignant tumors from the molecular level. The tumor necrosis factor related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor (TNF) super family, is a promising candidate, either alone or in combination with established cancer therapies, since it can initiate apoptosis through the activation of their death receptors. The ability of TRAIL to selectively induce apoptosis of transformed, virus-infected or tumor cells but not normal cells promotes the development of TRAIL-based cancer therapy. Here, we will review TRAIL and its receptors' structure, function, mechanism of action and application in ocular tumors therapy.
基金Key Program of Tenth Five-Year Plan and the 211 Key Subject Construction Foundation, No. 2002-2
文摘BACKGROUND: Receptors for tumor necrosis factor related apoptosis inducing ligand (TRAIL) include death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2. Activation of death receptor 4 and 5 selectively kills tumor cells. OBJECTIVE: To detect TRAIL receptor expression in glioblastoma by immunohistochemistry and RT-PCR, and to compare this expression to that in normal brain tissue. DESIGN: Observational analysis. SETTING: Department of Pathology, the First Affiliated Hospital of Zhengzhou University; Henan Tumor Pathology Key Laboratory. PARTICIPANTS: Twenty-five patients (17 males and 8 females) who received glioblastoma resection were selected from the Fifth Affiliated Hospital of Zhengzhou University, between September 2003 to June 2004. All glioblastoma samples were diagnosed pathologically. Twenty patients (12 males and 8 females) with craniocerebral injury who received normal brain tissue resection were selected in the same time period. There were no significant differences in sex and age between glioblastoma patients or between craniocerebral injury patients (P 〉 0.05). All patients and appropriate relatives provided informed consent, and this study was approved by the local research ethics committee. METHODS: Polyclonal antibody against TRAIL receptors and an immunohistochemical kit (batch number: 200502) were purchased from Boster Company, Wuhan. Immunohistochemistry: Expression of death receptor 4, death receptor 5, decoy receptor l, and decoy receptor 2 were observed in both glioblastoma and normal brain tissue. The experiment was performed according to the kit instructions, and positive staining was brown-yellow. Assessment: There were no positive signals (-); weakly positive signals, positive cells 〈 25% (+); weakly positive signals, positive cells 25%-50% (++); strongly positive signals, positive cells 50%-75% (+++); strongly positive signals, positive cells 〉 75% (++++). Evaluation: Expression levels of TRAIL receptors were estimated in both normal brain tissue and glioblastoma. Expression of decoy receptor 1 and decoy receptor 2 mRNA in glioblastoma were detected by reverse transcription polymerase chain reaction, and expression of decoy receptor in glioblastoma was estimated. MAIN OUTCOME MEASURES: Comparison of death receptor and decoy receptor protein expression between glioblastoma and normal brain tissue; decoy receptor mRNA expression in glioblastoma. RESULTS: Death receptor protein expression was strongly positive (+++) in glioblastoma, while it was weakly positive (+, ++) in normal brain tissue. Therefore, expression rate of death receptor protein in the glioblastoma was significantly higher than that in the normal brain tissue (.~ 2 = 18.48, 23.03, P 〈 0.01). Decoy receptor protein expression in the glioblastoma was significantly lower than that in the normal brain tissue ( x2 = 6.65, 18.76, P 〈 0.01). The level of decoy receptor mRNA expression in glioblastoma was significantly higher than those of protein expression ( x 2 = 9.82, 10.09, P〈 0.01). CONCLUSION: High expression of death receptor and low expression of decoy receptor are frequently observed in glioblastoma, suggesting that TRAIL receptor genes show an anti-tumor and expressive response during the initiation and development of the tumor. There are significant differences in decoy receptor expression between normal brain tissue and glioblastoma, suggesting that the restricted expression of decoy receptor in glioblastoma is regulated at the post-transcriptional level.
基金Supported by National Natural Science Foundation of China(No.81100665)
文摘AIM: To investigate the potential of pigment epitheliumderived factor(PEDF) to protect the immortalized rat retinal ganglion cells-5(RGC-5) exposed to Co Cl2-induced chemical hypoxia. METHODS: After being differentiated with staurosporine(SS), RGC-5 cells were cultured in four conditions: control group cells cultured in Dulbecco 's modified eagle medium(DMEM) supplemented with 10% fetal bovine serum, 100 μmol/m L streptomycin and penicillin(named as normal conditions); hypoxia group cells cultured in DMEM containing 300 μmol/m L Co Cl2; cells in the group protected by PEDF were first pretreated with 100 ng/m L PEDF for 2h and then cultured in the same condition as hypoxia group cells; and PEDF group cells that were cultured in the presence of 100 ng/m L PEDF under normal conditions. The cell viability was assessed by MTT assay, the percentage of apoptotic cells was quantified using Annexin V-FITC apoptosis kit, and intra-cellar reactive oxygen species(ROS) was measured by dichloro-dihydro-fluorescein diacetate(DCFH-DA) probe. The mitochondria-mediated apoptosis was also examined to further study the underlying mechanism of the protective effect of PEDF. The opening of mitochondrial permeability transition pores(m PTPs) and membrane potential(Δψm) were tested as cellular adenosine triphosphate(ATP) level and glutathione(GSH). Also, the expression and distribution of Cyt C and apoptosis inducing factor(AIF) were observed.RESULTS: SS induced differentiation of RGC-5 cells resulting in elongation of their neurites and establishing contacts between outgrowths. Exposure to 300 μmol/m L Co Cl2 triggered death of 30% of the total cells in cultures within 24 h. At the same time, pretreatment with 100 ng/m L PEDF significantly suppressed the cell death induced by hypoxia(P〈0.05). The apoptosis induced by treatment of Co Cl2 was that induced cell death accompanied with increasing intracellar ROS and decreasing GSH and ATP level. PEDF pretreatment suppressed these effects(P〈0.05). Additionally, PEDF treatment inhibited the opening of m PTPs and suppressed decreasing of Δψm in RGC-5 cells, resulting in blocking of the mitochondrial apoptotic pathway.CONCLUSION: Pretreatment of RGC-5 cells with 100 ng/m L PEDF significantly decreases the extent of apoptosis. PEDF inhibits the opening of m PTPs and suppresses decreasing of Δψm. Moreover, PEDF also reduces ROS production and inhibits cellular ATP level's reduction. Cyt C and AIF activation in PEDF-pretreated cultures are also reduced. These results demonstrate the potential for PEDF to protect RGCs against hypoxic damage in vitro by preventing mitochondrial dysfunction.
文摘BACKGROUND: Recent studies have demonstrated that tumor necrosis factor-like weak inducer of apoptosis (TWEAK) participates in brain edema. However, it is unclear whether blood-brain barrier (BBB) disruption is associated with TWEAK during the process of brain edema OBJECTIVE: To investigate the effects of TWEAK on BBB permeability in brain edema. DESIGN, TIME AND SETTING: An immunohistochemical observation, randomized, controlled animal experiment was performed at the Laboratory of Neurosurgical Anatomy, Xiangya Medical College, Central South University & Central Laboratory, Third Xiangya Hospital, Central South University between January 2006 and December 2007. MATERIALS: A total of 48 adult Wistar rats were randomly divided into three groups: normal control (n = 8), sham-operated (n = 8), and ischemia/reperfusion (n = 32). Rats from the ischemia/reperfusion group were randomly assigned to four subgroups according to different time points, i.e., 2 hours of ischemia followed by 6 hours (n = 8), 12 hours (n = 8), 1 day (n = 8), or 12 days (n = 8) of reperfusion. METHODS: Focal cerebral ischemia/reperfusion injury was induced by middle cerebral artery occlusion (MCAO) using the suture method in rats from the ischemia/reperfusion group. Thread was introduced at a depth of 17-19 mm. Rats in the sham-operated group were subjected to experimental procedures similar to the ischemia/reperfusion group; however, the introducing depth of thread was 10 mm. The normal control group was not given any intervention. MAIN OUTCOME MEASURES: TWEAK expression was examined by immunohistochemistry; brain water content on the ischemic side was calculated as the ratio of dry to wet tissue weight; BBB permeability was measured by Evans blue extravasation. RESULTS: A total of eight rats died prior to and after surgery and an additional eight rats were randomly entered into the study. Thus 48 rats were included in the final analysis. In the ischemia/reperfusion group, TWEAK-positive cells were present in the ischemic penumbra surrounding the lamellar necrotic region in the fight cerebral hemisphere at 6 hours reperfusion and increased thereafter; by 2 days reperfusion they had reached a peak level, which was significantly higher than the sham-operated and normal control groups (P 〈 0.05). At 6 hours reperfusion, both brain water content and Evans blue extravasation showed the same tendency for change as TWEAK expression. Pearson correlation analysis results revealed that the degree of TWEAK expression was positively correlated with brain water content (r = 0.892, P 〈 0.05). CONCLUSION: The present results confirmed that TWEAK was involved in BBB disruption and participated in brain edema following cerebral ischemia.
基金supported by the National Natural Science Foundation of China, No. 81160157projects of Science and Technology Bureau of Guizhou Province, No.20093075, 20072127
文摘Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid. Results showed that the survival rate of neurons was significantly increased after treatment with 4,4-diisothiocyanatostilbene-2,2'-disulfonic acid, and the rate of apoptosis decreased. In addition, the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor were significantly reduced. Our experimental findings indicate that the chloride channel blocker 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid can antagonize apoptotic cell death of hippocampal neurons by inhibiting the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor.
基金the National Natural Sciences Foundation of China(39470739)the Ministry of Public Health Research Foundation(20122167)the Doctor Startup-Natural Science Foundation of Li-aoning Province (20041047)
文摘Objective To study the effect of γ-interferon (IFNγ), tumor necrosis factor related apoptosis inducing ligand (TRAIL), and cisplatin or etoposide induced apoptosis in human neuroblastoma cell line SH-SY5Y and its possible molecular mechanisms.Methods The expressions of Caspase 8 mRNA and protein were detected with RT-PCR and Western blot analysis. The effects of IFNγ, TRAIL, IFNγ+TRAIL, IFNγ+Caspase 8 inhibitor+TRAIL, IFNγ+cisplatin+TRAIL, and IFNγ+etoposide+TRAIL on the growth and apoptosis of SH-SY5Y cells were detected with the methods of MTT and flow cytometry. The relative Caspase 8 activity was measured with colorimetric assay. Results Caspase 8 was undetectable in SH-SY5Y cells but an increased expression of Caspase 8 mRNA and protein was found after treatment with IFNγ. SH-SY5Y cells themselves were not sensitive to TRAIL, but those expressing Caspase 8 after treatment with IFNγ were. The killing effect of TRAIL on SH-SY5Y cells expressing Caspase 8 was depressed by Caspase 8 inhibitor. Cisplatin and etoposide could enhance the sensitivity of TRAIL on SH-SY5Y cells. The relative Caspase 8 activity of SH-SY5Y cells in IFNγ+TRAIL group was significantly higher than those of control group, IFNγ group, TRAIL group, and inhibitor group (P<0.01). There was no significant difference among IFNγ+TRAIL group, IFNγ+cisplatin+TRAIL group, and IFNγ+etoposide+TRAIL group.Conclusions IFNγ could sensitize SH-SY5Y cells to TRAIL-induced apoptosis and this may be realized by the upregulation of Caspase 8. Cisplatin and etoposide could enhance the killing effect of TRAIL on SH-SY5Y cells.
文摘Apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) can be regulated by the epidermal growth factor(EGF) signaling pathway.In this study,recombinant adenoviral vectors that encode TRAIL gene from the hTERT/RGD promoter(AdTRAIL) was combined with drugs including gefitinib,elotinib,and cetuximab that inhibit EGFR and the EGF signaling pathway in non-small cell lung cancer(NSCLC) cell lines to investigate their antitumor activity.In vitro,compared to single reagent,AdTRAIL combined with EGFR inhibitors reduced proliferation and enhanced apoptosis in H460,A549,and SW1573 cell lines.Western blot results suggested that these effects were relative to up-regulation of pro-apoptosis protein BAX and down-regulation of p-AKT.In vivo,AdTRAIL combined with cetuximab resulted in a significant growth reduction in H460 xenografts without damage to the main organs of nude mice.Histological examination and TUNEL analyses of xenografts showed that cetuximab enhanced cell apoptosis induced by AdTRAIL.These results indicate that EGFR inhibitors enhanced AdTRAIL anti-tumor activity in NSCLC cell lines and that inhibiting the AKT pathway played an important role in this enhancement.
基金Supported by Research grants from Merck KGaA,Darmstadt,Germany,to Schulze-Bergkamen H
文摘AIM:To analyze the effect of chemotherapeutic drugs and specific kinase inhibitors,in combination with the death receptor ligand tumor necrosis factor-related apoptosis inducing ligand(TRAIL),on overcoming TRAIL resistance in hepatocellular carcinoma(HCC)and to study the efficacy of agonistic TRAIL antibodies,as well as the commitment of antiapoptotic BCL-2 proteins, in TRAIL-induced apoptosis. METHODS:Surface expression of TRAIL receptors (TRAIL-R1-4)and expression levels of the antiapoptotic BCL-2 proteins MCL-1 and BCL-xL were analyzed by flow cytometry and Western blotting,respectively. Knock-down of MCL-1 and BCL-xL was performed by transfecting specific small interfering RNAs.HCC cellswere treated with kinase inhibitors and chemotherapeutic drugs.Apoptosis induction and cell viability were analyzed via flow cytometry and 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. RESULTS:TRAIL-R1 and-R2 were profoundly expressed on the HCC cell lines Huh7 and Hep-G2. However,treatment of Huh7 and Hep-G2 with TRAIL and agonistic antibodies only induced minor apoptosis rates.Apoptosis resistance towards TRAIL could be considerably reduced by adding the chemotherapeutic drugs 5-fluorouracil and doxorubicin as well as the kinase inhibitors LY294002[inhibition of phosphoinositol- 3-kinase(PI3K)],AG1478(epidermal growth factor receptor kinase),PD98059(MEK1),rapamycin(mam- malian target of rapamycin)and the multi-kinase inhibitor Sorafenib.Furthermore,the antiapoptotic BCL-2 proteins MCL-1 and BCL-xL play a major role in TRAIL resistance:knock-down by RNA interference increased TRAIL-induced apoptosis of HCC cells.Additionally, knock-down of MCL-1 and BCL-xL led to a significant sensitization of HCC cells towards inhibition of both c-Jun N-terminal kinase and PI3K.CONCLUSION:Our data identify the blockage of survival kinases,combination with chemotherapeutic drugs and targeting of antiapoptotic BCL-2 proteins as promising ways to overcome TRAIL resistance in HCC.
文摘Recent studies have demonstrated that Notch-1 expression is increased in the hippocampus of Alzheimer's disease patients. We speculate that Notch-1 signaling may be involved in PC12 cell apoptosis induced by amyloid beta-peptide (25-35) (Aβ25-35). In the present study, PC12 cells were cultured with different doses (0, 0.1, 1.0, 10 and 100 nmol/L) of N-[N-(3,5-Difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester, a Notch-1 signaling pathway inhibitor, for 30 minutes. Then cultured cells were induced with Aβ25-3s for 48 hours. Pretreatment of PC12 cells with high doses of N-[N-(3,5-Difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (〉 10 nmol/L) prolonged the survival of PC12 cells after Aβ25-35 induction, decreased the expression of apoptosis-related proteins caspase-3, -8, -9, increased the activity of oxidative stress-related superoxide dismutase and catalase, inhibited the production of active oxygen, and reduced nuclear factor kappa B expression. This study indicates that the Notch-1 signaling pathway plays a pivotal role in Aβ25-35-induced PC12 apoptosis.
基金supported by the National Natural Science Foundation of China,No.30471917 and 30770766
文摘Studies have demonstrated that DL-3-n-butylphthalide can significantly alleviate oxygen glucose deprivation-induced injury of human umbilical vein endothelial cells at least partly associated with its enhancement on oxygen glucose deprivation-induced hypoxia inducible factor-1α expression.In this study,we hypothesized that DL-3-n-butylphthalide can protect against oxygen glucose deprivation-induced injury of newborn rat brain microvascular endothelial cells by means of upregulating hypoxia inducible factor-1α expression.MTT assay and Hoechst staining results showed that DL-3-n-butylphthalide protected brain microvascular endothelial cells against oxygen glucose deprivation-induced injury in a dose-dependent manner.Western blot and immunofluorescent staining results further confirmed that the protective effect was related to upregulation of hypoxia inducible factor-1α.Real-time RT-PCR reaction results showed that DL-3-n-butylphthalide reduced apoptosis by inhibiting downregulation of pro-apoptotic gene caspase-3 mRNA expression and upregulation of apoptosis-executive protease bcl-2 mRNA expression;however,DL-3-n-butylphthalide had no protective effects on brain microvascular endothelial cells after knockdown of hypoxia inducible factor-1α by small interfering RNA.These findings suggest that DL-3-n-butylphthalide can protect brain microvascular endothelial cells against oxygen glucose deprivation-induced injury by upregulating bcl-2 expression and downregulating caspase-3 expression though hypoxia inducible factor-1α pathway.
基金ThisprojectwassupportedbyagrantfromClinicalSubjectKeyProgramFoundationofMinistryofPublicHealth (No .970 70 2 4 1)
文摘The expression of hypoxia inducible factor-1 alpha (HIF-1α) and its relationship to apoptosis in tissues around cerebral bleeding loci was studied. The expression of HIF-1α and apoptosis in 37 samples of tissues around cerebral bleeding loci and 9 samples of normal cerebral tissues was assessed by immunohistochemical straining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling methods. In 37 tissue samples around cerebral bleeding loci, the positive rate of the HIF-1α expression was 40.6 %. Especially in the patients with amount of bleeding>60 ml, the positive rate (88.9 %) of the HIF-1α expression was significantly higher than those with the amount of bleeding ranging from 30—45 ml or 45—60 ml (P<0.05). The expression of HIF-1α was increased as the amount of bleeding and operative time increased (P<0.05). There existed a positive correlation between HIF-1α labeling index and apoptosis index (n=12, r=0.56, P<0.01). These results suggested that the expression of HIF-1α was closely related with the time of hemorrhage and the amount of bleeding, and could induce the apoptosis of neurons.
基金supported by the Natural Science Fundation of Jilin Province in China, No.200705272
文摘Hypoxiainducible factor1 and its specific target gene heme oxygenase1, are involved in acute cerebral ischemia. However, very few studies have examined in detail the changes in the hy poxiainducible factor1/heme oxygenase1 signaling pathway in chronic cerebral ischemia. In this study, a rat model of chronic cerebral ischemia was established by permanent bilateral common carotid artery occlusion, and these rats were treated with intragastric cilostazol (30 mg/kg) for 9 weeks. Morris water maze results showed that cognitive impairment gradually worsened as the cerebral ischemia proceeded. Immunohistochemistry, semiquantitative PCR and western blot analysis showed that hypoxiainducible factorla and heme oxygenase1 expression levels in creased after chronic cerebral ischemia, with hypoxiainducible factorla expression peaking at 3 weeks and heme oxygenase1 expression peaking at 6 weeks. These results suggest that the elevated levels of hypoxiainducible factorla may upregulate heine oxygenase1 expression fol lowing chronic cerebral ischemia and that the hypoxiainducible factor1/heme oxygenase1 sig naling pathway is involved in the development of cognitive impairment induced by chronic cerebral ischemia. Cilostazol treatment alleviated the cognitive impairment in rats with chronic cerebral ischemia, decreased hypoxiainducible factorla and heme oxygenase1 expression levels, and reduced apoptosis in the frontal cortex. These findings demonstrate that cilostazol can protect against cognitive impairment induced by chronic cerebral ischemic injury through an antiapoptotic mechanism.