2-甲氧基雌二醇联合硼替佐米对多发性骨髓瘤细胞凋亡的影响

目的 探讨2-甲氧基雌二醇(2-ME2)联合硼替佐米的抗多发性骨髓瘤(MM)效应及与聚集小体(aggresome)形成之间的相关性.方法 以MM细胞系RPMI 8226、NCI-H929、U266、SKO-007细胞作为研究对象,采用硼替佐米单药或联合2-ME2处理,通过等效应线图法分析两者是否具有抗MM协同效应;通过免疫荧光技术在同一组细胞群中研究聚集小体阳性和阴性细胞的凋亡情况.结果 ①硼替佐米呈浓度和时间依赖性地显著提高聚集小体阳性细胞比例,且聚集小体几乎全部出现于非凋亡细胞中.②等效应线图法分析显示一定浓度范围的硼替佐米与2-ME2联合具有显著的协同作用.③硼替佐米与2-ME2联合应用后聚集小体阴性的凋亡细胞显著增多而聚集小体阳性的非凋亡细胞明显减少.在RPMI 8226及U266细胞中,硼替佐米单药与联合用药组相比,聚集小体阴性的凋亡细胞分别由(14.5±2.6)%及(20.1±2.9)%增加至(80.7±6.9)%及(71.6±6.2)%;聚集小体阳性的非凋亡细胞分别由(75.3±5.7)%及(69.1±8.6)%减少到(13.8±3.8)%及(19.5±4.2)%.结论 硼替佐米诱导生成的聚集小体对MM细胞具有保护作用;2-ME2通过抑制聚集小体途径可以显著增强硼替佐米的抗MM效应.     

ADMA通过引起脐静脉内皮细胞内质网应激而诱导细胞凋亡

目的探讨非对称性二甲基精氨酸(ADMA)是否通过内质网应激引起人脐静脉内皮细胞(HUVEC)凋亡。方法对HUVEC进行体外培养,通过流式细胞仪检测细胞凋亡水平,用RT-PCT检测CHOP mRNA和ATF4 mRNA水平,用Western blot检测RNA蛋白激酶的内质网类似激酶(PERK)、转录激活因子-4(ATF4)、转录因子C/EBP同源蛋白(CHOP)的蛋白水平。结果流式细胞仪结果表明ADMA引起HUVEC凋亡,RT-PCR结果表明ADMA引起CHOP mRNA和ATF4 mRNA表达增加,Western blot结果表明ADMA引起PERK、ATF4、CHOP蛋白表达明显增高。结论ADMA通过内质网应激而引起HUVEC凋亡,从而加快动脉硬化的进展。     

Endogenous hydrogen sulfide alleviates methotrexate-induced cognitive impairment by attenuating endoplasmic reticulum stress-induced apoptosis via CHOP and caspase-12

The aim of this study was to estimate whether methotrexate (MTX) promotes cognitive impairment via increased ER stress and disrupted H₂S signaling in the hippocampus and whether H₂S may alleviate MTX-induced cognitive impairment by inhibiting ER stress through CHOP and caspase-12. Cognitive impairment behaviors were observed by Morris water maze test, and the apoptosis of neurons was assessed by TUNEL assay. The production of neurons was analyzed by DCX and Ki67 immunohistochemistry. The expressions of CHOP and caspase-12 in the hippocampus were determined by Western blot and immunohistochemistry. MTX increased the expression of CHOP and caspase-12 and the number of TUNEL-positive cells in the hippocampus by inhibiting endogenous H₂S-induced neuronal pyknosis in the hippocampal CA1 region. MTX decreased the number of DCX- and Ki67-positive cells in the hippocampal DG region. The results of Morris water maze showed that MTX could damage the spatial memory of rats. The changes of MTX-induced Morris water maze test in mice and H₂S levels in serum and hippocampus, as well as the expression of CHOP and caspase-12 and the number of CHOP and caspase-12-positive neurons in the hippocampus, indicated that H₂S could alleviate the cognitive impairment induced by methotrexate through CHOP and caspase-12.     

Tanshinone IIA reduces palmitate-induced apoptosis via inhibition of endoplasmic reticulum stress in HepG2 liver cells

Research has indicated that stress on the endoplasmic reticulum (ER) of a cell affects the pathogenesis of metabolic disorders such as obesity, type 2 diabetes mellitus, and non-alcoholic fatty liver disease (NAFLD). Palmitate, a saturated fatty acid, is known to induce toxicity and cell death in various types of cells. Tanshinone IIA (Tan IIA), one of the effective components of the traditional Chinese medicine Danshen, was reported to exhibit a variety of biochemical activities, including amelioration of ER stress-mediated apoptosis in renal preservation. To address the hypothesis that tan IIA attenuates apoptosis and triglycerides (TG) accumulation via reducing ER stress, we studied the effect of tan IIA on experimentally induced ER stress using palmitate in HepG2 cells. Palmitate led to cytotoxicity, TG accumulation, and apoptosis in HepG2 cells and also strongly induced ER stress indicated by increased GRP78, phosphorylation of eIF2α, ATF6, and CHOP. Pretreatment with tan IIA (10 μm ) significantly increased cell viability, decreased apoptotic cell death, and reduced the activity of caspase-3. Meanwhile, tan IIA significantly decreased palmitate-induced TG accumulation. Moreover, tan IIA significantly suppressed the phosphorylation of eIF2α, and inhibited GRP78, ATF6, and CHOP expression. In conclusion, tan IIA protects the HepG2 cells exposed to palmitate partially by inhibiting excessive ER stress, ER stress-induced apoptosis, and hepatic steatosis. Therefore, tan IIA has therapeutic potential in the treatment of NAFLD.     

Ritonavir induces endoplasmic reticulum stress and sensitizes sarcoma cells toward bortezomib-induced apoptosis

The biosynthesis of immunoglobulin leads to constitutive endoplasmic reticulum (ER) stress in myeloma cells, which activates the unfolded protein response (UPR). The UPR promotes protein folding by chaperones and increases proteasomal degradation of misfolded protein. Excessive ER stress induces apoptosis and represents a molecular basis for the bortezomib sensitivity of myeloma. Most solid malignancies such as sarcoma, by contrast, are poorly bortezomib sensitive and display low levels of ER stress. We hypothesized that pharmacologic induction of ER stress might sensitize malignancies to bortezomib treatment. We show that the HIV protease inhibitor ritonavir induces ER stress in bortezomib-resistant sarcoma cells. Ritonavir triggered the UPR, decreased the degradation of newly synthesized protein, but did not directly inhibit proteasomal active sites in the therapeutic dose range in contrast to bortezomib. Whereas neither bortezomib nor ritonavir monotherapy translated into significant apoptosis at therapeutic drug levels, the combination strongly increased the level of ER stress and activated PERK, IRE1, and ATF6, synergistically induced CHOP, JNK, caspase-4, and caspase-9, and resulted in >90% apoptosis. In summary, ritonavir increases the level of ER stress induced by bortezomib, which sensitizes bortezomib-resistant cells to bortezomib-induced apoptosis. Ritonavir may therefore be tested clinically to improve the sensitivity of solid malignancies toward bortezomib treatment.     

滋补脾阴方药含药血清对内质网应激致神经元凋亡的影响

目的 运用中药血清药理学方法研究滋补脾阴方药含药血清对内质网应激致神经元凋亡作用及其机制.方法 实验中体内实验于辽宁省SPF动物重点实验室完成,体外实验于辽宁省脑疾病研究重点实验室完成.SPF级健康雄性SD大鼠(220～250 g)12只,随机分为对照组和滋补脾阴方药(ZBPYR)组,每组6只,制备空白及ZBPYR含药血清.以N-糖链抑制剂农霉素(tunicamycin,Tm,5压计μml)刺激小鼠神经瘤母细胞(Neuro2a)建立内质网应激模型,各浓度滋补脾阴方药含药血清(5%,10%,15%)为干预组,空白血清组为对照组,采用四甲基偶氮唑盐(MTT)方法观察Neuro2a细胞牛存率;流式细胞技术观察Neuro2a细胞凋亡;蛋白质免疫印迹(Western blotting)法观察葡萄糖调节蛋白78(GRP78)、凋亡促进因子CCAAT/增强子结合蛋白同源蛋白(CHOP)的蛋白表达.统计结果行SNK-q检验.结果 各浓度ZBPYR含药血清预处理组(生存率:5%0.5295±0.0373,10%0.5843±0.0428,15%0.6274±0.0324;凋亡率:5%47.8733±2.8166,10%46.3366±1.2748,15%39.8833±1.0524)与Tm组(牛存率:0.1673±0.0213;凋亡率:62.7050±1.4056)相比,细胞牛存率明显升高(P<0.05);细胞凋亡率显著降低(P<0.05);各浓度ZBPYR含药血清预处理组GRP 78(5%2.1228±0.2251,10%1.3293±0.9443.15%;15%0.0931±0.1168)及CHOP(5%1.1776±0.2927,10%0.7290±0.1708,15%0.6577±0.1883)蛋白表达与Tm组(GRP 78 2.9149±0.5355;CHOP 1.6611±0.2913)相比,表达水平明显下调(P<0.05).结论 ZBPYR能提高Tm刺激后的Neuro2a细胞生存率,抑制细胞凋亡,具有神经保护作用,其机制可能是减轻内质网应激及抑制内质网应激凋亡通路.     

内质网应激相关蛋白1对衣霉素诱导HepG2细胞内质网应激的影响

目的研究过表达内质网应激相关蛋白1(SERP1)对衣霉素诱导肝癌HepG2细胞内质网应激的影响。 方法以衣霉素诱导HepG2细胞发生内质网应激,将细胞分为以下5组：正常对照组、衣霉素组、衣霉素＋0.25μg SERP1转染组、衣霉素＋0. 5μg SERP1转染组和衣霉素＋1.0μg SERP1转染组,每组实验重复3次;采用MTT法检测不同浓度与作用时间的衣霉素对HepG2细胞存活率的影响,以吸光度(A)值表示。Western blot法检测各组细胞内内质网应激标志蛋白葡萄糖调节蛋白(GRP78)、C/EBP同源蛋白(CHOP)以及钙联蛋白的表达水平。采用SPSS 15.0统计软件进行统计学分析,比较蛋白表达水平。 结果与对照组相比,衣霉素处理组HepG2细胞中内质网应激标志性蛋白GRP78、CHOP及Calnexin蛋白表达量显著升高,分别为对照处理组的3.8倍(t＝11.5,P<0.05)、1.3倍(t＝3.498,P<0.05)和1.4倍(t＝4.1,P<0.05),差异均有统计学意义;随着SERP1过表达量的逐渐升高,变化呈现剂量依赖性。随着SERP1转染剂量的增加,各组GRP78蛋白的表达较单独衣霉素处理组分别下降了12%[(1.83±0.29)A值,(1.61±0.13)A值,t＝2.36,P>0.05]、24%和30%[(1.83±0.29)A值,(1.40±0.11)A值,(1.27±0.21)A值;F＝50.56,P<0.05],CHOP蛋白的表达水平分别下降了23%, 29%和34%[(1.0±0.15)A值,(0.79±0.07)A值,(0.72±0.55)A值,(0.67±0.14)A值;F＝9.532,P<0.05],Calnexin蛋白的表达水平分别下降了5%[(1.20±0.18)A值,(1.15±0.13)A值;P>0.05]、24%和28%[(1.20±0.18)A值,(0.92±0.07)A值,(0.87±0.18)A值;F＝8.116,P<0.05]。 结论外源性过表达SERP1蛋白通过下调内质网应激蛋白的表达,降低HepG2细胞内质网应激水平,缓解内质网应激介导的细胞损伤。     

间充质干细胞对多发性骨髓瘤细胞生长及硼替佐米诱导其凋亡的影响研究

目的 探讨间充质干细胞在多发性骨髓瘤细胞生长以及硼替佐米诱导骨髓瘤细胞凋亡中的作用.方法 取15例临床确诊的多发性骨髓瘤(MM)患者以及3名正常供者的骨髓标本,分离其间充质干细胞(MM-BMSC和ND-BMSC);测定细胞生长曲线、免疫表型和细胞因子分泌水平.将骨髓瘤细胞(NCI-H929)与BMSC细胞共培养,并加入蛋白酶体抑制剂硼替佐米,观察BMSC对NCI-H929细胞生长增殖的影响;进一步通过Annexin V-FITC/PI双染法流式细胞术(FCM)检测BMSC对硼替佐米诱导NCI-H929细胞凋亡的影响.结果 成功分离得到MM患者以及正常供者骨髓间充质干细胞,FCM检测显示两者均高表达CD73和CD105(＞95%),表达CD44和CD29,不表达CD31、CD34、CD45和HLA-DR(＜1%)等表面分子.生长曲线测定显示MM-BMSC增殖较为缓慢,倍增时间(82 h)较ND-BMSC(62 h)略有延长(P＜0.05).与ND-BMSC比较,MM-BMSC分泌高水平的细胞因子IL-6和VEGF,分别为(188.8±9.4)pg/ml对(115.0±15.1)pg/ml和(1497.2±39.7)pg/ml对(1329.0±21.1)pg/ml.将BMSC与骨髓瘤细胞NCI-H929共培养,MM-BMSC可促进骨髓瘤细胞的生存,降低NCI-H929细胞对硼替佐米的敏感性,明显抑制硼替佐米诱导的瘤细胞凋亡.结论 MM-BMSC可促进骨髓瘤细胞的生长,明显减少蛋白酶体抑制剂硼替佐米诱导的细胞凋亡.     

内质网应激介导成骨细胞凋亡在骨溶解骨组织中的作用及机制

背景：磨损微粒能够在体外诱导成骨细胞凋亡,但是发生骨溶解的骨组织中是否也存在成骨细胞的凋亡以及骨组织中的成骨细胞凋亡信号通过何种途径进行传导目前尚不清楚。目的：分析内质网应激反应在骨溶解骨组织中成骨细胞凋亡和骨溶解发生发展中的作用。方法：制备磨损微粒诱导骨溶解动物模型。实验分为4组：空白对照组只接受PBS的刺激;磨损微粒组只接受纳米合金粉末悬液的刺激;内质网应激阳性对照组接受纳米合金粉末＋毒胡萝卜素的刺激;内质网应激抑制组接受纳米合金粉末悬液及造模后当时、造模后1,2,3和5 d分别腹腔注射4-苯基丁酸。通过甲苯胺蓝染色、苏木精-伊红染色和碱性磷酸酶染色观察骨溶解的病理变化;分析骨溶解颅骨组织中成骨细胞分化成熟情况;Western Blot 方法检测骨溶解颅骨组织内内质网应激反应标志蛋白的表达变化;TUNEL 和 Caspase-3免疫组织化学方法检测骨溶解颅骨组织内成骨细胞的凋亡情况。结果与结论：磨损微粒能够在体外诱导小鼠颅骨骨溶解的发生、加重炎症细胞的浸润以及抑制成骨细胞分化成熟,同时磨损微粒还可以上调成骨细胞内质网应激反应标志蛋白以及促进骨溶解骨组织中成骨细胞的凋亡。经内质网应激抑制剂（4-苯基丁酸）的治疗后,骨溶解症状明显缓解,骨侵蚀和炎症浸润显著降低,成骨细胞的分化成熟得到改善,凋亡的成骨细胞急剧减少,内质网应激标志蛋白的表达逐渐减弱。表明内质网应激反应参与骨溶解的形成并在骨溶解的发生发展中发挥重要作用。提示内质网应激可作为一种新的治疗靶点,为临床逆转或治疗骨溶解和无菌性松动提供新的思路和方法。     

2-甲氧基雌二醇增强骨髓瘤细胞U266对硼替佐米敏感性的相关机制研究

本研究旨在探索2-甲氧基雌二醇(2-ME2)联合硼替佐米对人骨髓瘤细胞株U266的协同抑制增殖和诱导凋亡作用及其可能机制。2-ME2、硼替佐米单用以及二者联合分别处理U266细胞,用CCK8方法检测细胞增殖活力,caspase3/7活性法检测细胞凋亡,流式细胞术分析细胞周期的变化,荧光实时定量PCR检测P21、BAX、BCL-2等mRNA水平变化。结果表明:相比于2-ME2和硼替佐米单用,2-ME2联合硼替佐米处理U266细胞后,细胞增殖明显抑制(p<0.05),细胞凋亡增加(p<0.05),细胞周期阻滞于G1-S期;在mRNA水平,P21及BAX表达上调,BCL-2表达下调。结论:2-ME2联合硼替佐米能更有效地抑制U266细胞增殖和诱导凋亡,具有协同作用,其机制可能与其诱导P21及BAX表达上调有关。     

Homocysteine induces human mesangial cell apoptosis via the involvement of autophagy and endoplasmic reticulum stress

Homocysteine (Hcy) level characterizes a progressive increase in chronic kidney disease (CKD). In fact, Hcy accumulation is considered to be a crucial biochemical culprit in CKD progression, but the mechanism underlying this remains poorly understood. This study investigated the role of Hcy in glomerular mesangial cell (MC) apoptosis and the potential involvement of autophagy and endoplasmic reticulum (ER) stress in this process, shedding light on Hcy toxicity in kidney disease. Human mesangial cells (HMCs) were incubated with different concentrations of Hcy for different times. Flow cytometry was used to determine the proportion of apoptotic cells and western blotting was used to analyze protein levels after the administration of Hcy, endoplasmic reticulum inhibitor 4-phenylbutyric acid (4-PBA), and Atg5 siRNA. The results demonstrated that the cell viability gradually decreased and the proportion of HMCs undergoing apoptosis increased with increasing Hcy concentration and prolonged incubation time. Meanwhile, levels of the apoptosis-related proteins Bax and cleaved caspase-3 were significantly increased, while ER stress-related proteins such as ATF4, CHOP, GRP78, and phospho-eIF2α significantly increased. Levels of cleaved LC3, and beclin1 and Atg5 proteins also increased, accompanied by p62 degradation, indicating autophagy activation. 4-PBA effectively inhibited ER stress and reversed Hcy-induced apoptosis and autophagy. Moreover, Atg5 siRNA alleviated Hcy-induced apoptosis. Taken together, these results suggest that Hcy induces HMC apoptosis in a dose- and time-dependent manner via the activation of Atg5-dependent autophagy triggered by ER stress. This study suggests a novel strategy against Hcy toxicity in kidney injury and should help in clarifying the pathogenesis of CKD.

Homocysteine (Hcy) level characterizes a progressive increase in chronic kidney disease (CKD).     

Role of an endoplasmic reticulum Ca2+-independent phospholipase A2 in cisplatin-induced renal cell apoptosis

It has been demonstrated recently that rabbit renal proximal tubule cells (RPTC) express a novel Ca(2+)-independent phospholipase A(2) (iPLA(2)) whose activity localizes to the endoplasmic reticulum (ER-iPLA(2)) and is similar to group VIB PLA(2). In this study, the expression of group VIB PLA(2) was examined and the role of ER-iPLA(2) in cisplatin-induced apoptosis was determined. Cisplatin induced both time- and concentration-dependent RPTC apoptosis as determined by p53 nuclear localization, annexin V staining, caspase 3 activity, and chromatin condensation. Inhibition of ER-iPLA(2) with bromoenol lactone (5 microM) reduced cisplatin-induced annexin V binding 40%, chromatin condensation 55%, and caspase 3 activity 42%, but had no effect on p53 nuclear localization. Treatment of RPTC with the protein kinase C stimulator phorbol 12-myristate 13-acetate increased the activity of ER-iPLA(2) 2-fold and increased cisplatin-induced RPTC apoptosis. These studies demonstrate that group VIB PLA(2) is expressed in RPTC and suggest that RPTC ER-iPLA(2) is the rabbit homolog of group VIB PLA(2). These data also demonstrate that ER-iPLA(2) acts downstream of p53 and upstream of caspase 3 to mediate cisplatin-induced RPTC apoptosis. Finally, ER-iPLA(2) seems to be regulated by protein kinase C.     

Involvement of endoplasmic reticulum stress in myocardial apoptosis of streptozocin-induced diabetic rats

Apoptosis plays critical role in diabetic cardiomyopathy and endoplasmic reticulum stress (ERS) is one of intrinsic apoptosis pathways. For previous studies have shown that endoplasmic reticulum become swell in diabetic myocardium and ERS was involved in diabetes mellitus and heart failure, this study aimed to demonstrate whether ERS was induced in myocardium of streptozocin (STZ)-induced diabetic rats. We established type 1 diabetic rat model with STZ intraperitoneal injection, used echocardiographic evaluation, hematoxylin-eosin staining and the terminal deoxynucleotidyl transferase-mediated DNA nick-end labeling staining to identify the existence of diabetic cardiomyopathy and enhanced apoptosis in the diabetic heart. We performed immunohistochemistry, Western blot and real time PCR to analysis two hallmarks of ERS, glucose regulated protein78 (Grp78) and Caspase12. We found both Grp78 and Caspase12 had enhanced expression in protein and mRNA levels in diabetic myocardium than normal rat's, and Caspase12 was activated in diabetic heart. Those results suggested that ERS was induced in STZ-induced diabetic rats' myocardium, and ERS-associated apoptosis took part in the pathophysiology of diabetic cardiomyopathy.     

Protective effect of recombinant human erythropoietin in type II Gaucher disease patient cells by scavenging endoplasmic reticulum stress

Gaucher disease (GD) is an inherited disorder characterized by excessive accumulation of glucocerebroside in cells due to a non-functional glucocerebrosidase that is linked to programmed cell death pathways. Although clinical manifestations vary, type II GD is the most severe phenotype characterized by endoplasmic reticulum (ER) stress, neurological dysfunction, and anemia. Recombinant human erythropoietin (EPO) has been very popular for treating renal anemia and recently was shown to have extra-hematopoietic effects including neuroprotective properties. EPO's hematopoietic and neuroprotective effects prompted us to test EPO's beneficial action on type II GD patient cells. Initially, to examine the responsiveness of type II GD cells to EPO, the expression of the EPO receptor was determined at mRNA and protein levels. EPO effects on signaling pathways and ER stress in GD cells were also investigated. Finally, the proliferative effect of EPO on GD cells was verified. We found that EPO stimulated signaling pathways, enhanced the expression of glucocerebrosidase, reduced ER stress marker protein levels, and enhanced the proliferation rate of type II GD patient cells. This novel approach involving a beneficial role of EPO in GD should provide insights into new concepts for treating GD.     

Hyperthermia-induced cell death by apoptosis in myeloma cells.

We have analyzed by morphological (TEM) and histochemical (TUNEL reaction) criteria the type of cell death occurring in one case of human multiple myeloma after hyperthermia. Samples of cells examined immediately at the end of two treatments with a 15-day interval showed a significant degeneration, mostly demonstrating features of apoptosis (cell shrinkage, DNA fragmentation, karyorrhexis). The possible causes of the lag period between heating and apoptosis onset-expression are discussed.     

内质网应激凋亡信号途径在脓毒症脾淋巴细胞凋亡中的作用研究

目的 研究内质网应激凋亡信号途径在脓毒症脾淋巴细胞凋亡中的作用.方法 24只C57BL/6小鼠被随机分为模型组和假手术(sham)组,每组12只.用盲肠结扎穿孔术(CLP)制备脓毒症动物模型,术后24 h处死动物后取脾脏,用原位末端缺刻标记法(TUNEL)检测脾淋巴细胞凋亡,用逆转录一聚合酶链反应(RT-PCR)和蛋白质免疫印迹法(Western blotting)检测葡萄糖调节蛋白78(GRP78)和C/EBP同源蛋白(CHOP)的mRNA和蛋白表达.结果 CLP组脾淋巴细胞凋亡指数较sham组明显增加(52±17比5±3,P＜0.01);且CLP组GRP78和CHOP的mRNA和蛋白表达亦较sham组明显增加(GRP78 mRNA:0.807±0.122比0.314±0.107,CHOP mRNA:0.923±0.085比0.221±0.074;GRP78蛋白:5.216±1.351比2.733±0.421,CHOP蛋白:3.170±1.227比0.403±0.142,P均＜0.01).结论 脓毒症时脾淋巴细胞中存在内质网应激反应,并通过上调CHOP表达的机制诱导凋亡.     

Modulation of endoplasmic reticulum stress and cardiomyocyte apoptosis by mulberry leaf diet in experimental autoimmune myocarditis rats

Mulberry is commonly used as silkworm diet and an alternative medicine in Japan and China, has recently reported to contain many antioxidative flavanoid compounds and having the free radical scavenging effects. Antioxidants reduce cardiac oxidative stress and attenuate cardiac dysfunction in animals with pacing-induced congestive heart failure. Hence we investigated the cardioprotective effect of mulberry leaf powder in rats with experimental autoimmune myocarditis. Eight-week-old Lewis rats immunized with cardiac myosin were fed with either normal chow or a diet containing 5% mulberry leaf powder and were examined on day 21. ML significantly decreased oxidative stress, myocyte apoptosis, cellular infiltration, cardiac fibrosis, mast cell density, myocardial levels of sarco/endo-plasmic reticulum Ca(2+) ATPase2, p22(phox), receptor for advanced glycation end products, phospho-p38 mitogen activated protein kinase, phospho-c-Jun NH(2)-terminal protein kinase, glucose regulated protein78, caspase12 and osteopontin levels in EAM rats. These results may suggest that mulberry diet can preserve the cardiac function in experimental autoimmune myocarditis by modulating oxidative stress induced MAPK activation and further afford protection against endoplasmic reticulum stress mediated apoptosis.     

缬沙坦对内质网应激介导的高血压大鼠心肌细胞凋亡的影响

目的探讨缬沙坦对内质网应激介导的高血压大鼠心肌细胞凋亡的影响。方法选用10只WKY大鼠和20只自发性高血压大鼠为研究对象,并随机将后者分为两组:其中一组行缬沙坦药物干预,余所有大鼠给予等量生理盐水。16周后全部处死并留取标本行TUNEL法检测心肌细胞凋亡情况,免疫组织化学法检测GRP78蛋白的表达水平。结果高血压组大鼠心肌可见大量凋亡细胞且GRP78蛋白表达水平显著升高,缬沙坦干预组两组指标均明显降低。结论缬沙坦可有效抑制内质网应激介导的心肌细胞凋亡。     

Combination therapy with IFN-alpha plus bortezomib induces apoptosis and inhibits angiogenesis in human bladder cancer cells

In a recent study, we showed that the proteasome inhibitor bortezomib sensitizes human bladder cancer cells to IFN-induced cell death. Here, we characterized the molecular mechanisms underlying the antitumoral effects of the combination in more detail. Bortezomib synergized with IFN-alpha to promote apoptosis via a tumor necrosis factor-related apoptosis-inducing ligand-associated mechanism but did not inhibit production of proangiogenic factors (vascular endothelial growth factor, basic fibroblast growth factor, and interleukin-8) in human UM-UC-5 cells. In contrast, exposure to the combination did not increase the levels of apoptosis in human UM-UC-3 cells but did inhibit the production of basic fibroblast growth factor and vascular endothelial growth factor. Studies with tumor xenografts confirmed that combination therapy with bortezomib plus IFN-alpha was effective in both models but that the effects were associated with differential effects on tumor necrosis factor-related apoptosis-inducing ligand-associated apoptosis (predominant in UM-UC-5) versus inhibition of angiogenesis (predominant in UM-UC-3). Together, our results show that combination therapy with IFN-alpha plus bortezomib is effective but can work via different mechanisms (apoptosis versus angiogenesis inhibition) in preclinical models of human bladder cancer.     

姜黄素联合硼替佐米对骨髓瘤H929细胞增殖抑制与凋亡诱导作用及其机理

本研究旨在探讨姜黄素(curcumin)联合硼替佐米(bortezomib)对人多发性骨髓瘤(multiple myeloma,MM)细胞系H929细胞增殖和凋亡的影响,并进一步探讨其作用的相关机理。采用MTT法检测不同浓度的姜黄素和硼替佐米单用或联合应用对H929细胞的增殖抑制作用;采用流式细胞术(FCM)分析单用和联合用药时细胞的凋亡比率;采用RT-PCR法分析凋亡相关基因BCL-2、BAX及细胞周期相关蛋白cyclin D1的表达变化;采用免疫荧光染色法测定不同处理组NF-κB P65蛋白的分布变化。结果表明:姜黄素和硼替佐米单用及联合应用时均可抑制H929细胞的生长,呈剂量依赖性,联合用药在一定浓度范围内有协同效应;联用组细胞凋亡的比例明显高于单用组及对照组;与单用组相比,联用组cyclin D1,BCL-2基因表达下降,BAX升高。核因子NF-κB P65在单用组的胞核内的表达减弱,联合应用组NF-κB P65蛋白分布于胞浆。结论 :姜黄素与硼替佐米均可抑制H929细胞的生长增殖、促进凋亡,联合应用有协同效应。抑制核因子NF-κB的转录及影响其调节凋亡相关基因可能是作用机制之一。