糖皮质激素对人卵巢癌细胞系3A0增殖分化及对糖皮质激素受体表达的影响(英文)

目的:观察不同浓度地塞米松(Dex)对人卵巢癌细胞系(3AO)增殖及分化的影响及其对糖皮质激素受体(GR)的调节作用.方法:以不同浓度Dex处理3AO细胞,采用活细胞计数法观察细胞增殖,用氨基安替比林法测定碱性磷酸酶(AKP)活性;用酶联免疫法测定细胞标志抗原CA125水平的变化;用放射配体结合法测定GR的表达.结果:Dex对3AO细胞的增殖有抑制作用,同时伴有细胞形态的变化及AKP活性增高和CA125的表达下降.Dex对3AO细胞AKP活性的诱导作用可被RU486所阻断.在3AO细胞中存在糖皮质激素受体(GR),Dex对GR结合活性有下调作用.结论:Dex对3AO细胞有增殖抑制和诱导分化作用,这种作用是通过GR来介导的.     

银杏内酯B调控PAX6基因表达对人骨髓间充质干细胞增殖和成骨分化能力的影响

摘要：目的:探讨银杏内酯B（GB）对人骨髓间充质干细胞（hBMSCs）增殖和成骨分化的影响及可能机制。方法:不同浓度(10,20,40 mg·L-1)的GB作用hBMSCs细胞后,四甲基噻唑蓝染色法（MTT）检测细胞增殖,实时定量聚合酶链式反应PCR（RT-qPCR）检测细胞中配对盒基因6（PAX6）的mRNA表达,蛋白印迹（Western Blot）法检测细胞中PAX6蛋白表达。不同浓度(10,20,40 mg·L-1)的GB作用成骨诱导的hBMSCs细胞14 d后,RT-qPCR检测细胞中碱性磷酸酶（AKP）、骨钙素（OCN）和骨桥蛋白（OPN）的mRNA表达,Western Blot法检测细胞中AKP、OCN和OPN的蛋白表达。转染PAX6过表达载体至hBMSCs,上述相同方法观察过表达PAX6对hBMSCs增殖及AKP、OCN和OPN的mRNA和蛋白表达的影响。结果:GB作用hBMSCs后,细胞活性显著升高（P<0.05）,PAX6的mRNA和蛋白表达水平均显著升高（P<0.05）。GB作用成骨诱导的hBMSCs细胞14 d后,细胞中AKP、OCN和OPN的mRNA和蛋白表达水平均显著升高（P<0.05）。过表达PAX6后,hBMSCs活性显著升高（P<0.05）,成骨诱导的细胞中AKP、OCN和OPN的mRNA和蛋白表达水平均显著升高（P<0.05）。抑制PAX6表达且同时使用GB作用时（GB+si-PAX6）,hBMSCs活性及成骨诱导后细胞中AKP、OCN和OPN的mRNA和蛋白表达水平均显著低于只使用GB作用（GB+si-NC）（P<0.05）。结论:GB可促进hBMSCs增殖和成骨分化,其作用机制与上调PAX6表达有关。     

苔黑酚葡萄糖苷通过抑制糖皮质激素受体入核保护地塞米松诱导成骨细胞损伤作用北大核心CSCD

目的 考察苔黑酚葡萄糖苷对地塞米松(dexamethasone,DEX)诱导成骨细胞损伤的保护作用,并探讨其调控机制。方法 从新生小鼠颅盖骨提取并培养原代成骨细胞(osteoblast,OB),用DEX(1μmol·L^(-1))诱导成骨细胞损伤为模型。采用CCK-8法测定不同浓度苔黑酚葡萄糖苷及有无DEX干预下对成骨细胞增殖的影响;采用试剂盒进行成骨细胞碱性磷酸酶(ALP)染色和ALP活性测定;采用茜素红S染色观察骨矿化结节的形成;采用Annexin V-FITC法检测细胞凋亡情况;采用免疫荧光结合激光共聚焦显微镜观察细胞内糖皮质激素受体(glucocorticoid receptor,GR)的入核情况;采用Western blot法检测GR在细胞核、细胞质和全细胞中的蛋白表达,以及细胞中成骨特征蛋白CollagenⅠ、Runx2、Osterix(Osx)和Dlx5的表达。结果 与对照组相比,DEX组成骨细胞增殖、分化和矿化均明显降低(P<0.05、0.01),细胞凋亡明显升高(P<0.01);与模型组相比,苔黑酚葡萄糖苷组成骨细胞增殖、分化和矿化均明显升高(P<0.01),细胞凋亡明显降低(P<0.05)。与对照组相比,DEX组成骨细胞中GR在核内的表达明显升高(P<0.01),而GR在全细胞和细胞质中的表达明显降低(P<0.01),同时成骨特征蛋白表达也明显降低(P<0.01);与模型组相比,苔黑酚葡萄糖苷组GR在成骨细胞核内的表达明显降低(P<0.01),而GR在全细胞和细胞质中的表达明显升高(P<0.01),成骨特征蛋白的表达均明显升高(P<0.01),且呈剂量依赖关系。结论 苔黑酚葡萄糖苷能够改善DEX诱导的成骨细胞增殖、分化和矿化的抑制作用,并减少其凋亡,其作用机制与苔黑酚葡萄糖苷抑制GR入核,从而调控成骨相关蛋白表达有关。     

糖皮质激素受体介导的胰岛素抵抗及其拮抗剂研究进展

糖皮质激素（GC）是维持机体能量代谢平衡的重要激素之一：GC作用于靶组织，不仅有赖于循环中的GC浓度，还与糖皮质激素受体（GR）的表达相关：外源性及内源性的GC水平升高均会导致机体出现胰岛素抵抗以及与之紧密相关的多种代谢综合征症候，如血脂障碍、内脏性肥胖和高血压。本文对近年来GR介导的胰岛素抵抗及其受体拮抗剂的研究进展进行综述。     

地塞米松衍生物对K562细胞增殖的抑制作用及机制

目的：研究地塞米松衍生物对K562细胞的增殖抑制作用，并对其作用机制进行初步的探讨。方法：以地塞米松为原料合成并纯化得到新的衍生物。用不同浓度的地塞米松衍生物对K562细胞进行处理，通过MTT比色法检测细胞增殖抑制率，电镜法观察细胞凋亡的形态学变化，免疫细胞化学法测定细胞Bcl-2，Fas表达，比色法检测Caspase-3的活性变化。结果：地基米松衍生物能抑制K562细胞的增殖，使Bcl-2表达降低，Fas表达上调，Caspase-3活性增强，诱导K562细胞凋亡。结论：地塞米松衍生物可能通过诱导K562细胞凋亡而抑制细胞增殖。其诱导细胞凋亡的机制可能与抑制Bcl-2蛋白的表达，上调Fas受体，进而激活细胞内的Caspase-3有关。     

新型维甲酸衍生物ATPR对肿瘤细胞株SKOV3增殖及分化的影响

目的：探讨新型维甲酸衍生物4-氨基-2-三氟甲基苯基维甲酸酯（4-amino-2-trifluorometh—yl—phenylretinate,ATPR）对卵巢癌SKOV3细胞的增殖及分化作用。方法：ATPR作用于细胞株SKOV3后,MTT法检测细胞的增殖;吉姆萨染色法在倒置相差显微镜下观察加药处理前后细胞形态学变化;ELISA法检测卵巢癌标志物糖链抗原125（CAl25）;流式细胞术检测细胞周期的变化情况。结果：ATPR呈浓度依赖性抑制SK—OV3细胞增殖,明显抑制作用出现在药物作用48h,但在72h后则更显著;倒置显微镜下观察发现细胞形态学趋于成熟分化;SKOV3中CAl25水平下降;流式细胞仪测定G0／G1期细胞表达量增加,S期细胞表达量减少,细胞周期进程受影响,细胞阻滞在G0／G1期。结论：ATPR对SKOV3细胞具有抑制增殖和-定的诱导分化作用。     

对多发性骨髓瘤细胞株KM_3的糖皮质激素受体的研究

笔者用放射配体结合测定法对培养的人骨髓瘤细胞株KM_3的糖皮质激素受体(GR)进行了检测,数量为(24674±1631)位点/细胞,平衡解离常数(d)为(3.82±1.21)nmol/L。研究发现地塞米松抑制KM_3细胞株的增殖,起着直接的杀伤作用。     

马钱子碱对乳腺癌细胞MDA-MB-231作用的实验研究

目的本研究旨在观察马钱子碱（Brucine）对人乳腺癌细胞MDA-MB-231的增殖抑制和诱导凋亡作用,并分析Brucine在诱导细胞凋亡过程中对Bcl-2、Bax和Caspase-3蛋白表达的调控作用。方法人乳腺癌细胞株MDA-MB-231（雌激素受体阴性）细胞以L-15培养基体外培养,用MTT法测定Brucine对细胞的增殖抑制作用;倒置显微镜观察细胞形态;以碘化丙啶（PI）单染流式细胞仪检测细胞凋亡;AnnexinV-FITC/PI双染流式细胞术检测Brucine对MDA-MB-231的诱导凋亡作用;Western蛋白印迹法检测凋亡相关蛋白Bcl-2、Bax和Caspase3的表达。结果Brucine对MDA-MB-231细胞有明显的增殖抑制作用;观察到典型的细胞凋亡形态学特征性改变;流式细胞术PI染色结果显示随着Brucine浓度的增加细胞凋亡率逐渐增高并呈明显的浓度依赖,与对照组相比差异有显著性（P〈0.05）;早期凋亡率和晚期凋亡率先增加后降低,但死亡细胞逐渐增加;且随着Brucine浓度的增加抗凋亡基因Bcl-2表达水平明显降低,而促凋亡基因Bax和Caspase-3表达明显增高。结论Brucine能够诱导乳腺癌MDA-MB-231细胞凋亡,其分子机制可能与激活Bax、Caspase-3和抑制Bcl-2等凋亡调控基因有关。     

COPD患者氧化应激与糖皮质激素受体水平的相关性

目的探讨不同时期COPD患者全身氧化应激水平的变化及其与糖皮质激素受体的相关性。方法测定40例急性加重期COPD患者（A组）、30例稳定期COPD患者（B组）、15例健康吸烟者（C组）血浆中MDA、GSH含量,SOD活性,及外周血有核细胞糖皮质激素受体水平。结果①A组、B组、C组间：①血浆MDA含量呈下降趋势;②血浆GSH含量、SOD活性呈上升趋势;②外周血有核细胞GR水平呈递增趋势;③GR与血SOD、MDA、GSH的相关系数分别为0.593、-0.561、0.663,P〈0.05。结论①COPD患者在全身水平存在氧化/抗氧化失衡,尤以急性加重期患者更为明显;②COPD患者氧化应激增加是导致外周血有核细胞糖皮质激素受体水平下降的原因之一。     

右美托咪定调控miR-526b-3p/S100A4表达影响胰腺癌细胞增殖及凋亡的机制研究

摘要：目的:探讨右美托咪定（Dex）对胰腺癌细胞增殖、凋亡的影响及其可能作用机制。方法:应用MTT法检测Dex对人胰腺癌Capan-1细胞增殖的抑制作用;采用流式细胞术检测细胞凋亡率;实时荧光定量聚合酶链反应（qRT-PCR）与蛋白免疫印迹法检测Dex对微小RNA-526b-3p（miR-526b-3p）和钙结合蛋白A4（S100A4）表达的影响;检测miR-526b-3p过表达与干扰S100A4表达对Capan-1细胞增殖及凋亡的影响;双荧光素酶报告实验验证miR-526b-3p与S100A4的靶向作用关系;抑制miR-526b-3p表达验证Dex对Capan-1细胞增殖和凋亡的作用机制; Western blot法检测细胞周期蛋白1（CyclinD1）、B淋巴细胞瘤-2（Bcl-2）、p21、B淋巴细胞瘤-2相关蛋白（Bax）蛋白表达。结果:用不同浓度的Dex处理后,细胞抑制率、细胞凋亡率与miR-526b-3p、p21、Bax的表达水平显著高于对照组（P<0.05）,S100A4、CyclinD1、Bcl-2的表达水平显著降低（P<0.05）,且呈明显的浓度依赖性（P<0.05）;双荧光素酶报告实验与Western blot实验证实miR-526b-3p与S100A4存在靶向结合关系,且miR-526b-3p可负性调控S100A4的表达; miR-526b-3p过表达或干扰S100A4表达后细胞抑制率、细胞凋亡率与p21、Bax的表达水平显著升高（P<0.05）,CyclinD1、Bcl-2的表达水平显著降低（P<0.05）;抑制miR-526b-3p表达可逆转Dex对Capan-1细胞增殖与凋亡的作用。结论:Dex可通过调控miR-526b-3p/S100A4表达抑制胰腺癌细胞增殖并诱导细胞凋亡。     

Ursodeoxycholic acid amides as novel glucocorticoid receptor modulators

Ursodeoxycholic acid (UDCA) is used for the treatment of hepatic inflammatory diseases. Recent studies have shown that UDCA's biological effects are partly glucocorticoid receptor (GR) mediated. UDCA derivatives were synthesized and screened for ability to induce GR translocation in a high content analysis assay using the esophageal cancer SKGT-4 cell line. UDCA derivatives induced GR translocation in a time dependent manner with equal efficacy to that of dexamethasone (Dex) and with greatly increased potency relative to UDCA. The cyclopropylamide 1a suppressed TNF-α induced NF-κB activity and it induced GRE transactivation. 1a was unable to displace Dex from the GR ligand binding domain (LBD) in a competition experiment but was capable of coactivator recruitment in a time-resolved fluorescence energy transfer assay (TR-FRET). This represents a novel mechanism of action for a GR modulator. These derivatives could result in a new class of GR modulators.     

Effects of arsenic trioxide, all-trans-retinoic acid and dexamethasone on NB4 cell line

Background and the purpose of the study

Experimental and preclinical observations have indicated that combination therapy with all-trans-retinoic acid (ATRA) and arsenic trioxide (ATO) may strongly enhance their therapeutic effects in the treatment of acute promyelocytic leukemia (APL). Whilst dexamethasone (Dex) is routinely used for the control of APL- differentiation syndrome, its effect on the pharmacodynamics of ATO is not clear. Therefore, in this study, effects of therapeutic concentrations of ATO, ATRA and Dex and their sequential usages on the proliferation, differentiation and apoptosis in t(15;17)-positive NB4 cells was investigated.

Methods

Cells were treated with therapeutic concentrations of ATO, ATRA and Dex either as single or in combination and cell proliferation was assessed by XTT assay. Expression of CD11b as an indicator of cell differentiation and the percentage of 7-AAD positive cells as a marker of apoptosis were determined by flow cytometry.

Results

ATO, but not ATRA and Dex, decreased proliferation of the cells dose-dependently. Pre-treatment of the cells with any of the drugs did not alter the effects of other drugs on the proliferation. Pre-treatments with Dex blocked the apoptotic effect of ATO (1 µM).

Conclusion

No improvement or antagonistic effects was observed with the pretreatment/ combination of the ATO and ATRA on the differentiation and apoptosis of the cells. It is possible that concomitant usage of Dex with apoptotic doses of ATO in APL patients counteract therapeutic effects of ATO.     

Inhibition of Jun N-terminal kinase (JNK) enhances glucocorticoid receptor-mediated function in mouse hippocampal HT22 cells.

Mitogen-activated protein kinases (MAPKs), including Jun N-terminal kinase (JNK), promote inflammatory and proliferative responses to infection and other environmental stimuli including stress. Relevant to negative regulation of inflammatory pathways by glucocorticoids and the development of glucocorticoid resistance (observed in inflammatory disorders as well as certain neuropsychiatric disorders such as major depression), activation of JNK has been reported to inhibit glucocorticoid receptor (GR) function. In this study, the role of JNK pathways in modulating GR function was further investigated. Treatment of mouse hippocampal (HT22) cells with the selective JNK inhibitor, SP-600125 (0.1-10 microM), resulted in dose-dependent induction of GR-mediated MMTV-luciferase activity. SP-600125 also significantly enhanced dexamethasone-induced MMTV-luciferase activity, while increasing GR binding to the glucocorticoid responsive element, both in the presence and absence of Dex. Similar effects were observed in mouse fibroblast cells (LMCAT), and in HT22 cells treated with a JNK specific antisense oligonucleotide. The induction of GR-mediated function by SP-600125 was not due to altered cytosolic GR binding or GR protein expression or enhancement of GR nuclear translocation as determined by Western blot. Taken together, the data indicate that constitutive expression of JNK plays a tonic inhibitory role in GR function, which is consistent with findings that activation of JNK pathways inhibits GR. The data also identify potential pathways involved in the pathogenesis of the glucocorticoid resistance found in certain chronic immune/inflammatory diseases and subgroups of patients with major depression. Moreover, JNK pathways may represent a therapeutic target for normalization of GR function in these disorders.     

Crosstalk between activated forms of the aryl hydrocarbon receptor and glucocorticoid receptor

Pyrene, benzo[a]pyrene (BaP), and indeno[1,2,3-cd]pyrene (IND) are poly cyclic aromatic hydrocarbons (PAHs) with four to six annealed phenyl rings. Dexamethasone (Dex) is a synthetic agonist of glucocorticoids. The aryl hydrocarbon receptor (AhR) ligands, BaP and IND, did not directly activate the glucocorticoid receptor (GR), and Dex did not activate the AhR either. Whenever BaP and IND were added to Dex-treated cultures, they were present with Dex for longer periods, and higher enhancement of Dex-induced transactivation of the GR was found, which indicates that the freshly activated AhR is essential for synergistic interactions with the activated GR. The degree of enhancement of Dex-induced transactivation of the GR by PAHs, BaP ≈ IND > pyrene, paralleled the potency of PAHs in activating the AhR. This synergistic interaction was more distinct in ovarian granulosa cells (HO23) than in HepG2, 293T, or HeLa cells. In contrast, Dex suppressed AhR-mediated expressions, including AhR and cytochrome P450 (CYP) 1 A1 expressions. Dex also counteracted the BaP-induced decrease in cell viability. Crosstalk between the AhR and GR was independent of their expression levels. We concluded that the AhR functionally cross-reacts with the GR, through which transactivation activity of the GR is further enhanced, and in contrast, transactivation activity of the AhR is inhibited. This report shows the significance of in vitro endocrine-related results, which provide a clue for molecular studies of an interactive mechanism between the AhR and GR, and should be confirmed by future in vivo studies.     

Glucocorticoids decrease astrocyte numbers by reducing glucocorticoid receptor expression in vitro and in vivo

Glucocorticoids are stress hormones released from the adrenal cortex and their concentration is controlled by the hypothalamic-pituitary-adrenal axis. In this study, we investigated the effect of glucocorticoids on the number of astrocytes and glucocorticoid receptor (GR) expression in vitro and in vivo. Proliferation of cultured astrocytes was reduced following treatment with corticosterone and dexamethasone for 72 h. Corticosterone and dexamethasone also reduced GR expression in astrocytes. RU486, a GR antagonist, inhibited the reduction in both astrocyte proliferation and GR expression. Furthermore, GR knockdown by siRNA inhibited astrocyte proliferation. We also examined the effect of excessive glucocorticoid release on GR expression and the number of astrocytes in vivo by administering adrenocorticotropic hormone to rats for 14 days. GR expression was reduced in the prefrontal cortex and hippocampus and the number of astrocytes was reduced in the frontal cortex. Overall, our results suggest that glucocorticoids decrease the number of astrocytes by reducing GR expression.     

Escin enhances anti-rheumatoid arthritis effects of low dose glucocorticoids through up-regulation of glucocorticoid receptor

OBJECTIVE To investigate the anti-rheumatoid arthritis(RA) effect of Escin combined with low dose of GCs(dexamethasone, Dex) and its underlying mechanism. METHODS Adjuvant-induced rheumatoid arthritis rats and LPS-injured RAW 264.7 were used to investigate the anti-RA effects of Escin combined with low dose Dex in vivo and in vitro. In vivo experiment: rats were randomly divided into model group(AIA), dexamethasone high dose(Dex, 0.2 mg·kg~(-1)) group, dexamethasone low dose(Dex, 0.05 mg·kg~(-1))group, Escin 10 mg·kg~(-1) group, Dex 0.05+Escin group, 10 rats in each group, another 10 were used as normal control group. The vehicle and the corresponding drug were administered intragastrically(ig) daily for 14 d. In vitro experiment: LPS was used to stimulate RAW264.7 macrophages for inflammatory models, which were divided into control group, LPS group, Dex with high dose(50 nmol·L~(-1))group, and Dex with low dose(12.5 nmol·L~(-1)) group. In the Escin 10 μmol·L~(-1) group and the Dex+Escin(12.5 nmol·L~(-1)+10 μmol·L~(-1))group, the corresponding drugs were added to each well. After 2 h, LPS was added to induce inflammation. RESULTS Escin combined with low dose Dex significantly decreased arthritic index, serum IL-6 and TNF-α, improved paw swelling, and ameliorated the joint pathology immune organ pathology significantly. Gene chip results revealed that Nr3 c1(GR) altered significantly. And that GR activation by Escin and low dose Dex was confirmed both in vivo and in vitro. Furthermore, Escin combined with low dose Dex also significant increase GR mRNA expression. However, when suppression of GR by its specific inhibitor, the anti-RA effect of Escin combined with low dose Dex was abolished. CONCLUSION Escin combined with Dex reduces the dose of Dex, and exerts significant anti-RA effects,which could also reduce the adverse effects of Dex. This combination might be attributed to GR activation. This study might provide a new combination drugs for the treatment of RA.