地塞米松诱导红系细胞凋亡的观察

以ＦＶＡ病毒诱导ＢＡＬＢ／ｃ小鼠脾细胞形成的红系细胞（ｅｒｙｔｈｒｏｉｄｃｅｌ）为研究对象，在红系细胞凋亡抑制剂——红细胞生成素（ＥＰＯ）存在情况下，观察了地塞米松（Ｄｅｘ）对上述细胞凋亡的诱导作用。结果表明，在一定浓度范围内，随着Ｄｅｘ作用时间的延长，细胞逐步凋亡并出现特有的ＤＮＡ梯形（ＤＮＡｌａｄｄｅｒ），而且其ＤＮＡ断裂程度与Ｄｅｘ的作用浓度呈正相关。透射电镜的结果证实，经最适浓度（５×１０－５ｍｏｌ／Ｌ）Ｄｅｘ处理后，红系细胞出现核固缩，染色质凝聚，核周隙扩大，核破裂，胞浆近膜处出现空泡以及细胞破碎等程度不同的细胞凋亡特征。说明Ｄｅｘ可拮抗ＥＰＯ的作用，有效地诱导红系细胞凋亡     

ACTH-producing cells of 21-day-old rat fetuses after maternal dexamethasone exposure

Adrenocorticotrophic hormone (ACTH) is essential for developmental maturation of numerous organ systems during the fetal period and for adaptation to environmental challenges. Immunocytochemical and stereological methods were used in the present study to examine the effects of dexamethasone (Dx) administration during pregnancy on fetal rat pituitary ACTH-producing cells. Doses of 0.5, 0.5 and 1.0 mg Dx/kg body weight/day were given to the dams on 3 consecutive days starting on day 16 of gestation. Morphometric analysis of the ACTH-producing cells of fetuses at 21 days of gestation revealed significant inhibition by 24% and 27%, respectively, of cell volume and cell number after maternal Dx administration, whereas the volume of cell nuclei and volume density of ACTH-stained cells were insignificantly decreased. Immunocytochemical analysis showed reduced numbers, sizes and immunopositivity of ACTH cells of 21-day-old fetuses from Dx-treated dams as compared with the control group. Maternal Dx treatment in the period of intense differentiation of the hypothalamo-hypophyseal-adrenal system had an inhibitory effect on fetal function and proliferative activity of ACTH-producing cells at 21 days of gestation. Thus, inhibition of activity of fetal ACTH-producing cells may lead to adrenal suppression, modified activity of the hypothalamo-pituitary-adrenal axis and reduced body weight possibly causing lasting functional abnormalities.     

地塞米松诱导大鼠免疫细胞凋亡机制初探

报道了地塞米松诱导大鼠胸腺、脾细胞凋亡机制的初探。结果表明，地塞米松与这些器官的细胞共同培养不同时间，其糖皮质激素受体（ＧＣＲ）量发生变化，胸腺细胞ＧＣＲ量在培养１．５ｈ组为６７．７２±１５．２１（ｆｍｏｌ／１０６细胞），显著高于对照组３０．５７±８．２５及５ｈ组３６．９１±９．１７（Ｐ＜０．０５），脾细胞ＧＣＲ量各组差异不显著（Ｐ＞０．０５）。在细胞周期蛋白依赖抑制因子（ρ１６）实验中，观察到Ｐ１６阳性细胞数在１．５ｈ组多于对照组及５ｈ组。在形态学及生化实验中，对照组及１．５ｈ组，胸腺、脾细胞Ｇｉｅｍｓａ染色形态一致，其ＤＮＡ未见断裂带；而５ｈ组，胸腺：脾细胞可见核固缩、深染、核碎裂、体积小的凋亡细胞，其ＤＮＡ电泳可见典型“梯状”条带。由此，推测地塞米松通过ＧＣＲ的作用，影响细胞周期相关蛋白，进而诱导免疫细胞凋亡。     

Progesterone and dexamethasone differentially regulate the IGF-system in glial cells

IGF-1 is an important factor for myelin synthesis and hence possesses therapeutic potential in treating demyelinating disease such as multiple sclerosis. However, IGF-1 poorly crosses the blood–brain barrier. In this study, we investigated the effects of the sex steroid progesterone and the glucocorticoid dexamethasone on regulation of the IGF-system in glial cells. By means of quantitative PCR analysis, we demonstrate that progesterone upregulates IGF-1, the type 1 IGF receptor and IGFBP-2 in primary rat astrocytes and both IGF-1 and IGFBP-6 in OLN-93 oligodendroglial progenitor cells. In contrast, dexamethasone showed a negative effect on expression of IGF-1, the type 1 IGF receptor and the respective IGF binding proteins in both cell types. In oligodendrocytes, the differentiation marker CNPase was positively regulated by progesterone and negatively regulated by dexamethasone. Further, oligodendroglial cell migration was enhanced approximately 4-fold by progesterone. This study implicates progesterone as a positive regulator of IGF-system in glial cells and demonstrates a further biological function of progesterone in oligodendrocyte biology, namely stimulation of progenitor cell migration. Dexamethasone, on the other hand, is a negative regulator of the IGF-system in glial cells.     

人外周血树突状细胞培养和地塞米松对其分化的影响作用

目的分离培养和鉴定人外周血树突状细胞（DC）,以及探讨地塞米松对其分化的影响作用。方法密度梯度离心法分离人外周血单个核细胞,贴壁后加入GM-CSF、IL-4和LPS培养,部分组另加入地塞米松,观察细胞形态学、流式标志和DC与T淋巴细胞共培养后的增殖变化。结果外周血单核细胞诱导培养后具有DC形态学特征,CD83表达上调,CD14表达下调,DC与T淋巴细胞共培养后呈增殖反应。培养液中加入地塞米松后CD83表达下调,CD14表达上调,DC与T淋巴细胞共培养后增殖反应减弱。结论外周血单核细胞经联合细胞因子可诱导为DC;地塞米松可使DC在功能上处于不成熟状态。     

人外周血T淋巴细胞自噬现象的观察

目的：观察分离培养的人外周血T淋巴细胞的自噬现象。方法：密度梯度离心法及尼龙棉柱法分离健康成年人外周血T淋巴细胞，分空白组及地塞米松（DXM）组，培养72小时后观察细胞光镜及电镜形态学、MDC荧光染色，并用流式细胞仪检测自噬细胞比例变化。结果：①通过自然培养后人外周血T淋巴细胞可出现典型自噬细胞形态学改变。②空白组及DXM组72小时自噬细胞发生率与0小时比较有显著性差异。③DXM组与空白组72小时自噬细胞发生率有显著性差异。结论：人外周血T淋巴细胞存在自噬现象，DXM可诱导人外周血T淋巴细胞自噬。     

p63 - Key molecule in the early phase of epithelial abnormality in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is the most common lung disease predisposing lung cancer. To clarify the early phase of epithelial abnormalities in IPF, we used an in vitro squamous metaplasia model, transforming growth factor beta1 (TGF beta1)-treated airway epithelial cells (BEAS-2B). The model repeated the expression of squamous epithelial character, such as involucrin, and keratin 6 and 14. DNA microarray analysis disclosed a unique expression signature in TGF beta1-treated airway epithelial cells, 20 specifically up-regulated genes including p63, jagged 1 (jag1) and the genes of structure proteins. Western blotting and RT-PCR analysis revealed that DeltaNp63alpha was the dominant isoform of p63 in our experimental model. Immunohistochemical analysis demonstrated the expression of p63 and jag1 in lung tissues of IPF. Inhibition of p63 with siRNA caused the down-regulation of jag1 expression, but not of involucrin, or keratin 6 and 14. Interestingly, the up-regulation of p63 was totally suppressed by N-acetyl-l-cysteine (NAC), but not by dexamethasone or pirfenidone. Thus, the p63-jag1 pathway may be up-regulated at an early phase of epithelial abnormalities in IPF, which can be overcome by NAC even in the TGF beta1-rich milieu.     

地塞米松对癫痫大鼠脑组织内IgG免疫反应阳性细胞分布的影响

目的：研究地塞米松对大鼠脑免疫反应的影响,探讨其对某些类型癫痫的治疗机理。方法：美解眠致痫及致痫前后分别给予地塞米松的大鼠用免疫细胞化学法观察ＩｇＧ免疫反应阳性（ＩｇＧＩＲ）细胞在大鼠脑组织内分布。结果：致痫前给予地塞米松大鼠脑皮层和海马ＩｇＧＩＲ细胞数比单纯致痫组减少（Ｐ＜００１,Ｐ＜００５）;致痫后给予地塞米松组大鼠,只有海马ＩｇＧＩＲ细胞数比单纯致痫组增多（Ｐ＜００１）。结论：地塞米松对脑免疫反应的调节在某些类型癫痫的治疗中可能有一定意义。     

Preparation of an anti-dexamethasone monoclonal antibody and its use in development of a colloidal gold immunoassay

A lateral flow colloidal gold (CG) immunoassay strip has been developed for detection of dexamethasone (DEX) residues in milk samples. For this purpose, an anti-DEX monoclonal antibody (McAb), based on a DEX succinic anhydride derivative hapten, was prepared and characterized. The McAb showed a high specificity to DEX, the half inhibitory concentration of the antibody was 0.095?ng/mL, its limit of detection (LOD) was 0.017?ng/mL, and its linear range of detection was 0.034–0.265?ng/mL. The developed CG immunoassay had a visual cut-off value of 0.3?ng/mL in phosphate buffered saline (PBS) and 0.5?ng/mL in milk samples. Each test requires 10 min. Analysis of DEX in milk indicated that the results of strip assay had a strong agreement with indirect competitive enzyme-linked immunosorbent assay. Therefore, the CG immunoassay is a sensitive screening method for semi-quantitative and qualitative detection of DEX residues in milk samples.     

羧胺三唑与小剂量地塞米松合用对A549肺癌移植瘤生长抑制作用的研究

目的观察羧胺三唑（CAI）对A549肺癌移植瘤生长及肿瘤环境中肿瘤坏死因予-α含量和血管生成的影响,研究小剂量地塞米松（DEX）是否能通过降低肿瘤环境中肿瘤坏死因子-α含量和抑制血管生成增强CAI对移植瘤生长的抑制作用。方法向裸鼠腋下接种A549肺癌细胞,建立A549肺癌移植瘤模型,接种第2天随机分5组,并开始给药,分别是PEG400溶剂对照组（每天一次灌胃给药,0．1ml／10g体重）、CAI组（每天一次灌胃给药,20mg／kg）、DEX组（每周两次背部皮下注射给药,1mg／kg）、CAI与DEX合用组（CAI,每大一次灌胃给药,20mg／kg;DEX,每周两次背部皮下注射给药,1mg／kg）及英夫利昔单抗组（每周两次腹腔注射给药,10mg／kg）。40d后剥离瘤组织,拍照并称重;将部分新鲜肿瘤组织速冻后制作冰冻切片,进行CD31荧光染色;另一部分新鲜瘤组织制各匀浆后用ELISA方法对其TNF—α含量进行检测。结果CAI、DEX和TNF—α抗体（英夫利昔单抗）对移植瘤生长均有抑制作用,而CAI与DEX的联合应用抑癌作用最强,PEG、CAI、DEX、COM和TAB组瘤重分别为（0．23±0．04）、（0．21±0．02）、（0．17±0．04）、（0．12±0．03）和（0．17±0．04）g。CD31血管染色显示,CAI和DEX均能减少肿瘤组织内的血管数目,两者合用在极大程度上抑制了血管的生成;CAI能够降低肿瘤组织内TNF-α含量,与DEX合用使TNF-α含量降至更低水平,PEG、CAI、DEX、COM和TAB组肿瘤组织匀浆中TNF-α的含量分别为（933．9±286．8）、（636．1±157．4）、（684．9±170．1）、（364．7±50．1）和（606．8±190．3）pg／mg蛋白。结论CAI不仅能够直接影响肿瘤细胞的增殖和凋亡,还能通过调控肿瘤环境中的TNF-α抑制血管的生成,从而减缓肿瘤的生长,这可能是CAI发挥抗肿瘤作用一个新的机制。小剂量DEX与CAI联合用药对移植瘤生长的抑制作用明显增强,优化了CAI的抗肿瘤作用,可能成为一种新的联合用药方案。