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1.
Objective  The aim of this study was to test the protective effect of mesenchymal stem cells (MSCs) on cardiomyocytes in vitro and to investigate the anti-apoptotic signaling pathway. Methods  MSCs from Sprague-Dawley (SD) rats were separated and cultured. MSC medium was collected from MSCs cultured in serum-free Dulbecco’s modified eagle medium (DMEM) under hypoxia. Cultured cardiomyocytes from neonatal SD rats were exposed to hypoxia/reoxygenation (H/R) and treated with MSC medium. The apoptotic cardiomyocytes were stained with Annexin-V-fluorescein isothiocyanate (FITC), Hoechst 33342 and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL). The mitochondrial transmembrane potential of cardiomyocytes was assessed using a fluorescence microscope. The expression of Bcl-2, Bax, cytochrome C, apoptosis-induced factor (AIF), and caspase-3 was tested by Western blot analysis. Results  Our data demonstrated that MSC medium reduced H/R-induced cardiomyocyte apoptosis, increased the Bcl-2/Bax ratio, and reduced the release of cytochrome C and AIF from mitochondria into the cytosol. Conclusion  MSCs protected the cardiomyocytes from H/R-induced apoptosis through a mitochondrial pathway in a paracrine manner. Project supported by the National Natural Science Foundation of China (No. 30670868) and the Natural Science Foundation of Zhejiang Province, China (No. R206007)  相似文献   

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4.
Background： Edaravone had been validated to effectively protect against ischemic injuries. In this study, we investigated the protective effect of edaravone by observing the effects on anti-apoptosis, regulation of Bcl-2/Bax protein expression and recovering from damage to mitochondria after OGD （oxygen-glucose deprivation）-reperfusion. Methods： Viability of PC 12 cells which were injured at different time of OGD injury, was quantified by measuring MTT （2-（4,5-dimethylthia-zol-2-yl）-2,5-diphenyltetrazolium bromide） staining. In addition, PC 12 cells＇ viability was also quantified after their preincubation in different concentration of edaravone for 30 min followed by （OGD）. Furthermore, apoptotic population of PC 12 cells that reinsulted from OGD-reperfusion with or without preincubation with edaravone was determined by flow cytometer analysis, electron microscope and Hoechst/Pl staining. Finally, change of Bcl-2/Bax protein expression was detected by Western blot. Results： （1） The viability of PC12 cells decreased with time （1-12 h） after OGD. We regarded the model of OGD 2 h, then replacing DMEM （Dulbecco＇s Modified Eagle＇s Medium） for another 24 h as an OGD-reperfusion in this research. Furthermore, most PC 12 cells were in the state of apoptosis after OGD-reperfusion. （2） The viability of PC 12 cells preincubated with edaravone at high concentrations （1, 0.1, 0.01 μmol/L） increased significantly with edaravone protecting PC 12 cells from apoptosis after OGD-reperfusion injury. （3） Furthermore, edaravone attenuates the damage of OGD-reperfusion on mitochondria and regulated Bcl-2/Bax protein imbalance expression after OGD-reperfusion. Conclusion： Neuroprotective effects of edaravone on ischemic or other brain injuries may be partly mediated through inhibition of Bcl-2/Bax apoptotic pathways by recovering from the damage of mitochondria.  相似文献   

5.
This paper aims to investigate the effects of artesunate (ART) on growth and apoptosis in human osteosarcoma HOS cell line in vitro and in vivo and to explore the possible underlying mechanisms. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The induction of apoptosis was detected by light and transmission electron microscopy and flow cytometry. Western blot analysis was used to investigate the related mechanisms. Nude mice were further employed to investigate the antitumour activity of ART in vivo. MTT assay results demonstrated that ART selectively inhibits the growth of HOS cells in a dose- and time-dependent manner. Based on the findings of light and transmission electron microscopy, Hoechst 33258 staining, and fluorescein isothiocyanate (FITC)-annexin V staining, the cytotoxicity of ART in HOS cells occurs through apoptosis. With ART treatment, cytosolic cytochrome c was increased, Bax expression was gradually upregulated, Bcl-2 expression was downregulated, and caspase-9 and caspase-3 were activated. Thus, the intrinsic apoptotic pathway may be involved in ART-induced apoptosis. Cell cycle analysis by flow cytometry indicated that ART may induce cell cycle arrest at G2/M phase. In nude mice bearing HOS xenograft tumours, ART inhibited tumour growth and regulated the expressions of cleaved caspase-3 and survivin, in agreement with in vitro observations. ART has a selective antitumour activity against human osteosarcoma HOS cells, which may be related to its effects on induction of apoptosis via the intrinsic pathway. The results suggest that ART is a promising candidate for the treatment of osteosarcoma.  相似文献   

6.
Human thioredoxin reductase (TrxR) system is associated with cancer cell growth and anti-apoptosis process. Effects of 1,2-[bis(1,2-benzisoselenazolone-3(2H)-ketone)]ethane (BBSKE), a novel TrxR inhibitor, were investigated on human leukemia cell lines HL-60 and K562. BBSKE treatment induced cell growth inhibition and apoptosis in both cell lines. Apoptosis induced by BBSKE is through Bcl-2/Bax and caspase-3 pathways. Ehrlich's ascites carcinoma-bearing mice were used to investigate the anti-tumor effect of BBSKE in vivo. Tumor-bearing mice treated with BBSKE showed an increase of life span with a comparable effect to cyclophosphamide (CTX). These results suggest a potential usage of BBSKE as a therapeutic agent against non-solid tumors.  相似文献   

7.

Objective

Mesenchymal stem cell (MSC) transplantation is a promising therapy for ischemic heart diseases. However, poor cell survival after transplantation greatly limits the therapeutic efficacy of MSCs. The purpose of this study was to investigate the protective effect of angiopoietin-1 (Ang1) preconditioning on MSC survival and subsequent heart function improvement after transplantation.

Methods

MSCs were cultured with or without 50 ng/ml Ang1 in complete medium for 24 h prior to experiments on cell survival and transplantation. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Hoechst staining were applied to evaluate MSC survival after serum deprivation in vitro, while cell survival in vivo was detected by terminal deoxynucleotidyl transferase biotin-dUPT nick end labeling (TUNEL) assay 24 and 72 h after transplantation. Heart function and infarct size were measured four weeks later by small animal echocardiography and Masson??s trichrome staining, respectively.

Results

Ang1 preconditioning induced Akt phosphorylation and increased expression of Bcl-2 and the ratio of Bcl-2/Bax. In comparison with non-preconditioned MSCs, Ang1-preconditioned cell survival was significantly increased while the apoptotic rate decreased in vitro. However, the PI3K/Akt pathway inhibitor, LY294002, abrogated the protective effect of Ang1 preconditioning. After transplantation, the Ang1-preconditioned-MSC group showed a lower death rate, smaller infarct size, and better heart functional recovery compared to the non-preconditioned-MSC group.

Conclusions

Ang1 preconditioning enhances MSC survival, contributing to further improvement of heart function.  相似文献   

8.
This study probed the protective effect of recombinant Lactobacillus plantarum against hydrogen peroxide(H_2O_2)-induced oxidative stress in human umbilical vein endothelial cells(HUVECs). We constructed a new functional L. plantarum(NC8-p SIP409-alr-angiotensin-converting enzyme inhibitory peptide(ACEIP)) with a double-gene-labeled non-resistant screen as an expression vector. A 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2 H-tetrazolium bromide(MTT) colorimetric assay was carried out to determine the cell viability of HUVEC cells following pretreatment with NC8-p SIP409-alr-ACEIP. Flow cytometry(FCM) was used to determine the apoptosis rate of HUVEC cells. Cysteinyl aspartate specific proteinase(caspase)-3/8/9 activity was also assayed and western blotting was used to determine protein expression of B-cell lymphoma 2(Bcl-2), Bcl-2-associated X protein(Bax), inducible nitric oxide synthase(i NOS), nicotinamide adenine dinucleotide phosphate oxidase 2(gp91 phox), angiotensin II(Ang II), and angiotensin-converting enzyme 2(ACE2), as well as corresponding indicators of oxidative stress, such as reactive oxygen species(ROS), mitochondrial membrane potential(MMP), malondialdehyde(MDA),and superoxide dismutase(SOD). NC8-p SIP409-alr-ACEIP attenuated H_2O_2-induced cell death, as determined by the MTT assay. NC8-p SIP409-alr-ACEIP reduced apoptosis of HUVEC cells by FCM. In addition, compared to the positive control, the oxidative stress index of the H_2O_2-induced HUVEC(Hy-HUVEC), which was pretreated by NC8-p SIP409-alr-ACEIP, i NOS,gp91 phox, MDA, and ROS, was decreased obviously; SOD expression level was increased; caspase-3 or-9 was decreased, but caspase-8 did not change; Bcl-2/Bax ratio was increased; permeability changes of mitochondria were inhibited; and loss of transmembrane potential was prevented. Expression of the hypertension-related protein(Ang II protein) in HUVEC cells protected by NC8-p SIP409-alr-ACEIP decreased and expression of ACE2 protein increased. These plantarum results suggested that NC8-p SIP409-alr-ACEIP protects against H_2O_2-induced injury in HUVEC cells. The mechanism for this effect is related to enhancement of antioxidant capacity and apoptosis.  相似文献   

9.
Objective: To determine whether spinal cord decompression plays a role in neural cell apoptosis after spinal cord injury. Study design: We used an animal model of compressive spinal cord injury with incomplete paraparesis to evaluate neural cell apoptosis after decompression. Apoptosis and cellular damage were assessed by staining with terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate nick-end labelling (TUNEL) and immunostaining for caspase-3, Bcl-2 and Bax. Methods: Experiments were conducted in male Spragne-Dawley rats (n=78) weighing 300-400 g. The spinal cord was compressed posteriorly at T10 level using a custom-made screw for 6 h, 24 h or continuously, followed by decompression by removal of the screw. The rats were sacrificed on Day 1 or 3 or in Week 1 or 4 post-decompression. The spinal cord was removed en bloc and examined at lesion site, rostral site and caudal site (7.5 mm away from the lesion). Results: The numbers of TUNEL-positive cells were significantly lower at the site of decompression on Day l, and also at the rostral and caudal sites between Day 3 and Week 4 post-decompression, compared with the persistently compressed group. The numbers of cells between Day 1 and Week 4 were immunoreactive to caspase-3 and B-cell lymphoma-2 (Bcl-2)-associated X-protein (Bax), but not to Bcl-2, correlated with those of TUNEL-positive cells. Conclusion: Our results suggest that decompression reduces neural cell apoptosis following spinal cord injury.  相似文献   

10.
The aim was to investigate how the PI3K/Akt pathway is involved in the protection of dexmedetomidine against propofol. The hippocampal neurons from fetal rats were separated and cultured in a neurobasal medium. Cell viability was assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Then neurons were pretreated with different concentrations of dexmedetomidine before 100 μmol/L propofol was added. Akt, phospho-Akt (p-Akt), Bad, phospho-Bad (p-Bad), and Bcl-xL were detected by Western blot. Also, neurons were pretreated with dexmedetomidine alone or given the inhibitor LY294002 before dexmedetomidine pretreatment, and then propofol was added for 3 h. The results demonstrated that propofol decreased the cell viability and the expression of p-Akt and p-Bad proteins, increased the level of Bad, and reduced the ratio of Bcl-xL/Bad. Dexmedetomidine pretreatment could reverse these effects. The enhancement of p-Akt and p-Bad induced by dexmedetomidine was prevented by LY294002. These results showed that dexmedetomidine potently protected the developing neuron and this protection may be partly mediated by the PI3K/Akt pathway.  相似文献   

11.
Background:Bone marrow mesenehymal stem cell(MSC)transplantation is a promising strategy in the treatment of myocardial infarction(MI).However,the time for transplanting cells remains controversial.The aim of this study was to find an optimal time point for cell transplantation.Methods:MSCs were isolated and cultured from Sprague-Dawley(SD) rats.MI model was set up in SD rats by permanent ligation of left anterior descending coronary artery.MSCs were directly injected into the infarct berder zone at 1 h,1 week and 2 weeks after MI,respectively.Sham-operated and MI centrel groups received equal volume of phosphate buffered saline(PBS).At 4 weeks after MI,cardiac function Was assessed by echocardiography;vessel density Was analyzed on hematoxylin-eosin stained slides by light microscopy;the apoptosis of cardiomyocytes Was evaluated by terminal deoxynucleotidy1 transferase-mediated dUTP nick end-labeling(TUNEL) assay;the expressions of proteins were analyzed by Western blot.Results:MSC transplantation improved cardiac function.reduced the apoptosis of cardiomyocytes and increased vessel density.These benefits were more obvious in l-week group than in 1-h and 2-week groups.There are more obvious increases in the ratio of bc1-2/bax and the expression of vascular endothelial growth factor(VEGF)and more obvious decreases in the expression of cleaved-caspase-3 in 1-week group than those in other two groups.Conclusion:MSC transplantation was beneficial for the recovery of cardiac function.MSC transplantation at l week post-MI exerted the best effects on increases of cardiac function,anti-apoptosis and angiogenesis.  相似文献   

12.
论文通过文献资料法、逻辑分析法等对骨髓间充质干细胞作用于心肌细胞凋亡应用,以及心肌细胞凋亡与Bcl-2和Bax蛋白表达的关系进行研究,旨在探讨骨髓间充质干细胞调控Bcl-2、Bax基因蛋白表达的方式对心肌细胞凋亡的作用机制。研究发现,心肌细胞凋亡与Bcl-2、Bax基因蛋白的表达存在高度相关性,通过调控Bcl-2、Bax的基因表达能够在一定程度上防止心肌细胞凋亡的发生与发展,而骨髓间充质干细胞则可以通过自身诱导分化的特性有效的调控Bcl-2和Bax蛋白的表达,使损伤后的心肌功能得到改善。  相似文献   

13.
探讨PFOS对雄性小鼠睾丸细胞凋亡以及相关基因表达的影响。40只雄性昆明系小鼠随机分成PFOS 0、1.25、2.5、5.0和10.0 mg/kg,共5组,通过饮水方法染毒35天。处死小鼠,取睾丸,流式细胞仪观察细胞凋亡RT-PCR观察Bax和Bcl-2基因表达。细胞凋亡率随着PFOS的浓度增加而增加,各剂量组与对照组比较均有显著性差异;10mg/kg/d PFOS实验组小鼠睾丸组织中Bax基因表达与对照组比较显著上升(p<0.05),其他剂量组变化与对照组比较差异无统计学意义(p>0.05)。随着染毒剂量的增加,Bcl-2基因表达下降,5.0、10.0 mg/kg/d PFOS实验组与对照组相比差异有统计学意义(分别为p<0.05,p<0.01)PFOS能够引起睾丸细胞凋亡增加,Bax和Bcl基因表达改变可能是其机制之一。  相似文献   

14.
通过用MTT法测定药物对MCF-7细胞的细胞毒作用,倒置显微镜观察细胞形态,LDH法测定凋亡和坏死的比率,Western blot方法分析药物作用后对MCF-7细胞中Bcl-2家族蛋白的表达,得出了在MCF-7细胞凋亡过程中,吴茱萸碱上调Bcl-2蛋白表达,下调Bax表达的结论。  相似文献   

15.
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16.
The aim of this study is to investigate the effects and possible mechanisms of sodium ferulate (SF) on anti-apoptosis in steroid-induced femoral head osteonecrosis in rabbits. Japanese white rabbits were randomly divided into three groups (control group, treatment group, and model group), each with 24 rabbits. The model and treatment groups were first injected with an intravenous dose of horse serum, 10 ml/kg, three weeks later with an intravenous dose of 7.5 ml/kg, and two weeks later with an intramuscular dose of methylprednisolone, 45 mg/kg, three times in order to establish rabbit models of osteonecrosis. Concurrently, the treatment group was injected with intravenous doses of SF 20 mg/kg for two weeks, once per day. Three time points, Weeks 2, 4, and 8, were selected after modeling was completed. Osteonecrosis was verified by histopathology with haematoxylin-eosin (HE) staining. The apoptosis rate of osteonecrosis was observed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The apoptosis expressions of caspase-3 and Bcl-2 were analyzed by immunohistochemistry and Western blot. The rabbit models of osteonecrosis were successfully established and observed by HE staining. SF was effective in intervening in apoptosis and decreasing the apoptosis rate in femoral head necrosis by the immunohistochemistry and TUNEL assay (P<0.01). Western blot analysis indicated that there were statistical significances in the protein levels of caspase-3 and Bcl-2 (P<0.01). SF has a protective effect by reducing the incidence of early steroid-induced femoral head necrosis in rabbits, effectively intervening in apoptosis through decreasing caspase-3 expression and up-regulating Bcl-2 expression.  相似文献   

17.
This article is to summarize the molecular and functional analysis of the gene “suppression of tumorigenicity 13” (ST13). ST13 is in fact the gene encoding Hsp70 interacting protein (Hip), a co-factor (co-chaperone) of the 70-kDa heat shock proteins (Hsc/Hsp70). By collaborating with other positive co-factors such as Hsp40 and the Hsp70-Hsp90 organizing protein (Hop), or competing with negative co-factors such as Bcl2-associated athanogen 1 (Bag1), Hip facilitates may facilitate the chaperone function of Hsc/Hsp70 in protein folding and repair, and in controlling the activity of regulatory proteins such as steroid receptors and regulators of proliferation or apoptosis. Although the nomenclature of ST13 implies a role in the suppression of tumorigenicity (ST), to date available experimental data are not sufficient to support its role in cancer development, except for the possible down-regulation of ST13 in gastric and colorectal cancers. Further investigation of this gene at the physiological level would benefit our understanding of diseases such as endocrinological disorders, cancer, and neurodegeneration commonly associated with protein misfolding.  相似文献   

18.
Objective: To determine the effects of albumin administration on lung injury and apoptosis in traumatic/hemorrhagic shock (T/HS) rats. Methods: Studies were performed on an in vivo model of spontaneously breathing rats with induced T/HS; the rats were subjected to femur fracture, ischemia for 30 min, and reperfusion for 20 min with Ringer’s lactate solution (RS) or 5% (w/v) albumin (ALB), and the left lower lobes of the lungs were resected. Results: Albumin administered during reperfusion markedly attenuate...  相似文献   

19.
目的:探讨人参皂苷Rg1对高血糖所致心肌损害的保护作用及其机制。创新点:使用糖尿病大鼠为实验对象,探讨三种浓度的人参皂苷Rg1对糖尿病心肌损伤的保护作用及其机制,检测其是否具有浓度依赖性。方法:将60只Wistar大鼠随机分组,其中空白对照组10只,另50只给予高脂高糖饲养,4周后腹腔注射40 mg/kg链脲佐菌素(STZ)。成功制备糖尿病大鼠模型40只,再随机分为糖尿病模型组,糖尿病大鼠+低剂量人参皂苷Rg1(10 mg/(kg·d)),糖尿病大鼠+中剂量人参皂苷Rg1(15 mg/(kg·d)),糖尿病大鼠+高剂量人参皂苷Rg1(20 mg/(kg·d))。12周后处死大鼠,取血测定空腹血糖、总胆固醇(TC)、甘油三酯(TG)、心肌酶及氧化应激水平,留取心肌组织使用透射电镜观察心肌细胞超微结构改变,应用TUNEL法检测心肌细胞凋亡,免疫组化检测细胞凋亡相关蛋白半胱氨酸天冬氨酸蛋白酶3(CASP3)和Bcl-x L的表达。结论:人参皂苷Rg1对糖尿病大鼠糖脂代谢无明显影响,人参皂苷Rg1可降低糖尿病大鼠血清肌钙蛋白(c Tn I)和肌酸激酶同工酶(CK-MB)水平,改善心肌细胞超微结构,减少心肌细胞凋亡,降低大鼠血清和心肌组织中丙二醛(MDA)含量,提高超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH)水平,降低凋亡蛋白CASP3的表达,同时提高Bcl-x L蛋白表达。总之,人参皂苷Rg1能显著保护糖尿病大鼠心肌损伤,其机制可能与其抗氧化及抗细胞凋亡作用有关。  相似文献   

20.
This article is to summarize the molecular and functional analysis of the gene "suppression of tumorigenicity 13"(ST13). ST13 is in fact the gene encoding Hsp70 interacting protein (Hip), a co-factor (co-chaperone) of the 70-kDa heat shock proteins (Hsc/Hsp70). By collaborating with other positive co-factors such as Hsp40 and the Hsp70-Hsp90 organizing protein (Hop), or competing with negative co-factors such as Bc12-associated athanogen 1 (Bag1), Hip facilitates may facilitate the chaperone function of Hsc/Hsp70 in protein folding and repair, and in controlling the activity of regulatory proteins such as steroid receptors and regulators of proliferation or apoptosis. Although the nomenclature of ST13 implies a role in the suppression of tumorigenicity (ST), to date available experimental data are not sufficient to support its role in cancer development, except for the possible down-regulation of ST13 in gastric and colorectal cancers. Further investigation of this gene at the physiological level would benefit our understanding of diseases such as endocrinological disorders, cancer, and neurodegeneration commonly associated with protein misfolding.  相似文献   

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