碱性成纤维细胞生长因子对大鼠肾小球系膜细胞原癌基因c—fos和c—…

在建立大鼠肾小球系膜细胞体外培养方法的基础上,通过＾３Ｈ－ＴｄＲ参入实验,ＲＮＡ印迹分析和斑点杂交观察ｂＦＧＦ对ＭＣ ＤＮＡ合成及原癌基因ｃ－ｆｏｓ和ｃ－ｍｙｃ表达的影响。     

大黄素对肾小球系膜细胞PCNA的影响

本文应用体外肾小球系膜细胞培养和免疫组化染色技术,以增殖细胞核抗原(PCNA)为标志抗原,观察了大黄素对肾小球系膜细胞周期调控的影响。发现大黄素能明显抑制系膜细胞从G_1期进入S期,同时对已进入S期细胞的进一步过渡也有影响。     

前列腺素F2α对大鼠肾小球系膜细胞DNA合成的影响

本实验应用（＾３Ｈ）胸腺嘧啶核苷（＾３Ｈ－ＴｄＲ）掺入法测定前列腺素Ｆ２α（ＰＧＦ２α）对大鼠肾小球系膜细胞ＤＮＡ合成的作用,测定系膜细胞合成的二脂酰甘油（ＤＡＧ）及磷酸肌醇（ＩＰ）。结果表明,ＰＧＦ２α促进系膜细胞的ＤＮＡ合成、ＤＡＧ及ＩＰ的生成。提示ＰＧＦ２α使系膜细胞的磷脂酶Ｃ活化,产生ＩＰ及ＤＡＧ,激活蛋白激酶Ｃ,从而促进ＤＮＡ合成及细胞增殖。     

高氨基酸血症对肾小球系膜细胞结缔组织生长因子表达的影响及与氧化应激的关系

目的研究高氨基酸血症对肾小球系膜细胞结缔组织生长因子（connective tissue growth factor,CTGF）表达的影响,探讨氧化应激在其中的作用。方法大鼠肾小球系膜细胞分为不同培养环境下的对照组（C组）、高氨基酸组（HA组）、维生素E组（HA。组）。培养24h后用荧光染料2’,7’-Dichloroluorescin diacetate（20μmoL／L）测定各组细胞内活性氧产物（reactive oxygen specie,ROS）的生成情况从而反应细胞内氧化应激水平,培养24h后采用RT-PCR检测各组CTGFmRNA表达,培养48h后采用Western印迹检测各组CTGF蛋白的表达。结果HA组氧化应激水平、CTGFmRNA及蛋白的表达均明显高于C组（P〈0.05）;HA。组其氧化应激水平、CTGFmRNA及蛋白表达较HA组明显降低（P〈0．05）,且与C组比较差异无统计学意义（P〉0．05）。结论高氨基酸血症可使肾小球系膜细胞氧化应激水平升高并产生过多的CTGF,抗氧化剂维生素E可减轻系膜细胞氧化应激及CTGF的表达,提示高氨基酸诱导的CTGF表达增多可能与氧化应激有关。     

缬沙坦对人肾小球系膜细胞糖基化终产物受体表达的影响

目的：本实验探讨缬沙坦对糖基化终产物诱导的人肾小球系膜细胞氧化应激水平及糖基化终产物受体（RAGE）表达的影响。方法：体外常规培养人肾小球系膜细胞,运用糖基化修饰的牛血清白蛋白（AGE-BSA）和缬沙坦进行干预,流式细胞术检测细胞内活性氧（ROS）,RT-PCR法检测NADPH氧化酶的亚基p47^phox的mRNA表达,RT-PCR和细胞免疫化学法检测RAGE的表达量。结果：缬沙坦干预组人肾小球系膜细胞的ROS产生量、NADPH氧化酶的亚基p47^phox mRNA表达量、RAGE表达量均低于AGE-BSA组（P〈0．05）,且缬沙坦的抑制作用呈浓度和时间依赖性。结论：缬沙坦可能通过降低氧化应激水平来抑制RAGE的表达。     

人肾小球系膜细胞葡萄糖转运蛋白的研究

本文采用了RT-PCR,细胞免疫荧光染色及流式细胞仪分析技术证实人肾小球系膜细胞有GLUT1(glucose transportorl)mRNA和蛋白质的表达。用2-Deoxy[~3H]-D-Glucose摄入法与根皮素抑制实验肯定了系膜细胞上GLUT1的功能及其在系膜细胞葡萄糖摄入中的作用。本项研究为进一步研究系膜细胞GLUT1在糖尿病肾病发病机理中的作用奠定了基础。     

Tolrestat对高糖所致肾小球系膜细胞肌动蛋白去组装的影响

研究了醛糖还原酶抑制剂Tolrestat对高浓度葡萄糖(HG)所致肾小球系膜细胞(MC)肌动蛋白(actin)组装的影响。结果证明,与正常浓度葡萄糖(NG)相比,在HG培养的MC,F-actin失去束状外观呈不规则网状,显示F-actin部分去组装;F-actin荧光强度降低,G-actin荧光强度升高和F-/G-actin荧光强度比值下降。Tolrestat加入培养后,明显防止HG引起的F-actin去组装及F-和G-actin荧光强度的变化。提示多元醇通路激活在HG引起的MCactin去组装改变中起一定作用。     

转化生长因子-β蛋白及mRNA基因在人类系膜增生性肾小球肾炎中的表达

目的：探讨转化生长因子－β（TGF－β）蛋白及mRNA基因在系膜增生性肾小球肾炎中的表达及其在发病中的作用。方法：采用常规病理,免疫组织化学及原位杂交方法对人系膜增生性肾小球肾炎组织进行染色,并经医学图像分析系统进行分析,结果：在正常对照组,TGF－β蛋白及TGF－β1mRNA小肾小管上皮细胞呈极弱表达,肾小球内TGF－β蛋白及mRNA未见阳性表达,在系膜增生肾小球肾炎组织中,TGF－β蛋白在肾近曲小管上皮细胞胞浆内呈强阳性表达,肾小球球囊壁及系膜区呈阳性,肾小球与肾小管阳性表达与正常对照组相比均具有显性差异（P＜0．01）,TGF－β1mRNA阳性表达位于肾近曲小管上皮细胞胞浆内和肾小球系膜区,肾小球和肾小管上皮细胞TGF－β1mRNA阳性表达与正常对照组相比差异也有显性（P＜0．01）。结论：系膜增生性肾小球炎时TGF－β蛋白及TGF－β1mRNARNA阳性表达与正常对照组相比差异也有显性（P＜0．01）。结论：系膜增生性肾小球肾炎时TGF－β蛋白及TGF－β1mRNA在肾小球与肾小管表达均显增高,进一步显示TGF－β在肾小球系膜细胞增生及肾小管间质纤维化中所起的重要作用。     

高糖刺激下大鼠肾小球系膜细胞CTGF和MT1-MMP的表达

目的观察高糖刺激的大鼠肾小球系膜细胞结缔组织生长因子(CTGF)和膜型基质金属蛋白酶-1(MT1-MMP)的动态变化,探讨糖尿病肾病(DN)的发病机制。方法体外培养的大鼠HBZY-1肾小球系膜细胞分为正常糖对照组,高糖组和甘露醇高渗对照组,采用RT-PCR及Western印迹法分别检测CTGF和MT1-MMP的mRNA及蛋白的表达,用酶联免疫吸附法(ELISA)检测培养上清中IV型胶原的含量。结果与对照组相比,高糖组各时间点系膜细胞CT-GF表达明显上调,IV型胶原的分泌增加,且二者随时间持续增高;而MT1-MMP的表达则随时间呈明显下降趋势。结论高糖可诱导肾小球系膜细胞CTGF表达增加,同时抑制MT1-MMP的表达,二者可能参与DN中细胞外基质(ECM)代谢失衡过程。     

Opposite Regulation of Basic Fibroblast Growth Factor and Nerve Growth Factor Gene Expression in Rat Cortical Astrocytes Following Dexamethasone Treatment

Abstract: Growth factors are peptides that exert different activities in the CNS, supporting the survival of different cell populations and playing an important role in the maintenance of cell homeostasis. Much evidence has suggested that these molecules can protect neurons from degeneration induced by mechanical injury or excitotoxic stimuli. Different factors can contribute to the regulation of neurotrophic factor expression in the brain. Such mechanisms may therefore be important in the manipulation of the levels of these peptides in specific brain areas as a therapeutic intervention in acute and chronic neurodegenerative diseases. We have used a primary culture of rat cortical astrocytes to investigate the regulation of basic fibroblast growth factor (bFGF) gene expression in comparison with other neurotrophic molecules. Our results indicate that the glucocorticoid analogue dexamethasone markedly elevates bFGF mRNA levels but reduces the expression of nerve growth factor. The induction of bFGF was transient, as it peaked after 6 h and returned to basal levels within 24 h and was not blocked by coincubation of cycloheximide, thus indicating that it did not require de novo protein synthesis. This effect was also observed in vivo, as systemic injection of dexamethasone (1 or 10 mg/kg) produced a significant increase in the amount of bFGF mRNA in cerebral cortex and hippocampus. The effect we describe can contribute to the regulation of bFGF expression in the brain and may be important in relation to the protective effect exerted by this growth factor in different models of neuronal injury.     

重组人碱性成纤维细胞生长因子(bFGF)融合蛋白的高效表达及鉴定

碱性成纤维细胞生长因子（ｂＦＧＦ）参与了许多细胞生长和分化的调控过程。本文采用重组ＤＮＡ技术在大肠杆菌中高效表达了人ｂＦＧＦ。首先将编码人ｂＦＧＦ基因克隆到ｐＸＴ表达载体中与其上游的一短Ｓ导肽共一阅读框架,ｂＦＧＦ基因的表达受强的Ｔ７启动子调控。采用ＢＬ２１（ＤＥ３）大肠杆菌作为宿主菌,用ＩＰＴＧ诱导ＢＬ２１（ＤＥ３）细菌合成的Ｔ７ＲＮＡ聚合酶,后者可催化高水平的ｂＦＧＦ基因表达,其ｂＦＧＦ产量可占总菌体蛋白的４２.５％。采用肝素Ｓｅｐｈａｒｏｓｅ一步亲和层析法直接从诱导后的细菌裂解产物中得到纯化的重组人ｂＦＧＦ蛋白。经Ｗｅｓｔｅｒｎ印迹分析证明该蛋白可被人ｂＦＧＦ特异性单克隆抗体所识别。进一步研究证明该蛋白具有刺激ＮＲ６Ｒ－３Ｔ３成纤维细胞增殖的生物学活性,并且这一活性可被人ｂＦＧＦ特异性中和抗体所中和。     

Regulation of Tyrosine Hydroxylase Gene Expression in IMR-32 Neuroblastoma Cells by Basic Fibroblast Growth Factor and Ciliary Neurotrophic Factor

Abstract: The actions of basic fibroblast growth factor (bFGF) and ciliary neurotrophic factor (CNTF) on tyrosine hydroxylase (TH) gene expression were studied using IMR-32 neuroblastoma cells. Treatment of these cells with bFGF for 3 days induced the expression of detectable levels of immunoreactive TH protein and TH mRNA. In contrast, CNTF did not affect TH expression unless bFGF was present. In the presence of saturating amounts of bFGF, CNTF increased TH protein and mRNA levels of TH two- to threefold over those found in bFGF-treated cultures. The effects of CNTF on TH expression diminished with increasing culture time, and after 6 days of incubation CNTF no longer enhanced TH levels. The requirement for bFGF as cofactor in the effects of CNTF on TH was specific, as CNTF did not affect TH when it was coadministered with 8-(4-chlorophenylthio)-cyclic AMP, another agent that stimulates TH development in this cell line, and bFGF was not required for CNTF to stimulate the development of choline acetyltransferase. Moreover, cotreatment with bFGF reduced the ability of CNTF to enhance choline acetyltransferase. These results demonstrate that bFGF and CNTF can enhance expression of TH and that bFGF can modify the effects of CNTF on neurotransmitter phenotype.     

Expression of Biologically Active Basic Fibroblast Growth Factor by Genetically Modified Rat Primary Skin Fibroblasts

Abstract: Basic fibroblast growth factor (FGF-2) is normally expressed as a cell-associated protein, and accordingly it is not clear how it exerts its action on target cells in vivo. It has been proposed that cells release, by death or other mechanisms, small amounts of FGF-2 that then acts in an autocrine manner. To address the question of whether it is necessary that FGF-2 remain cell associated or needs to be secreted from cells to have biological activity, we expressed the 18-kDa form of FGF-2 in primary fibroblasts as a cell-associated (FGF-2-B) or as a secreted (FGF-2-S) protein. FGF-2 protein is detected in cell lysates and membrane fractions of both cell types, whereas it is present in significant amounts only in the conditioned medium of FGF-2-S cells. No FGF-2 is detected in control (untransfected) cells. FGF-2-S cells also grow faster than the control or FGF-2-B cells. Yet, when evaluated for their ability to promote the survival of embryonic hippocampal neurons in vitro, both the cell types are active, establishing the activity of the transgene product. We conclude that FGF-2 is active when engineered to be expressed as a cell-associated form or secreted from cells.     

Deposition of Basic Fibroblast Growth Factor on Surface of Epidermal Melanocytes Suggesting the Stromal Control of Epidermal Pigmentation

Scanning electron microscopy with immunogold labeling was used to demonstrate the in vivo distribution of molecules of basic fibroblast growth factor (bFGF) that were expressed and/or present on the surface of the cells of the normal epidermis and dermal connective tissue of humans. We found that molecules of bFGF, seen as deposits of gold particles, were present densely on the surfaces of the melanocytes but not the epidermal keratinocytes. In connective tissue, these molecules were present exclusively on the surfaces of the fibroblasts, macrophages, vascular endothelial cells, and the basement membrane surrounding the endothelial tube. The selective deposition of bFGF molecules on the melanocytes suggests that the dermal connective tissue may be involved in controlling the proliferation of melanocytes by means of bFGF molecules in vivo, since these melanocytes require bFGF to proliferate in vitro. The latter is synthesized and stored exclusively in the connective tissue.     

Localization of Basic Fibroblast Growth Factor in Bovine Adrenal Chromaffin Cells

Abstract: We have investigated basic fibroblast growth factor (FGF-2) localization in and release from isolated bovine adrenal chromaffin cells. In contrast to previous reports, we found no evidence of fibroblast growth factor (FGF) storage in catecholamine-containing chromaffin granules. Subcellular fractionation studies did not show enrichment of FGF-2 immunoreactivity in granules, and cholinergic stimulation failed to release FGF-2 into the medium. Our results suggest that adrenal chromaffin cells resemble other FGF-2-synthesizing cell types with respect to FGF storage and secretion.     

碱性成纤维细胞生长因子对牙周膜细胞内核心蛋白多糖基因表达的影响

利用外源性碱性成纤维细胞生长因子(Basic Fibroblast Growth Factor,bFGF)刺激体外培养的人正常牙周膜细胞.采用逆转录-聚合酶链式反应(RT-PCR)检测细胞内decorin的基因表达的变化,研究bFGF对体外培养的人牙周膜细胞内核心蛋白多糖(decorin)的作用,进一步探讨bFGF抑制Ⅰ型胶原的作用机制.发现bFGF刺激牙周膜细胞后能促进牙周膜细胞的增殖,bFGF抑制decorin的合成是bFGF促进牙周膜细胞增殖的重要调节因素之一.     

Effects of Nerve Growth Factor and Basic Fibroblast Growth Factor Promote Human Dental Pulp Stem Cells to Neural Differentiation

Dental pulp stem cells (DPSCs) were the most widely used seed cells in the field of neural regeneration and bone tissue engineering, due to their easily isolation, lack of ethical controversy, low immunogenicity and low rates of transplantation rejection. The purpose of this study was to investigate the role of basic fibroblast growth factor (bFGF) and nerve growth factor (NGF) on neural differentiation of DPSCs in vitro. DPSCs were cultured in neural differentiation medium containing NGF and bFGF alone or combination for 7 days. Then neural genes and protein markers were analyzed using western blot and RT-PCR. Our study revealed that bFGF and NGF increased neural differentiation of DPSCs synergistically, compared with bFGF and NGF alone. The levels of Nestin, MAP-2, βIII-tubulin and GFAP were the most highest in the DPSCs?+?bFGF?+?NGF group. Our results suggested that bFGF and NGF signifiantly up-regulated the levels of Sirt1. After treatment with Sirt1 inhibitor, western blot, RT-PCR and immunofluorescence staining showed that neural genes and protein markers had markedly decreased. Additionally, the ERK and AKT signaling pathway played a key role in the neural differentiation of DPSCs stimulated with bFGF?+?NGF. These results suggested that manipulation of the ERK and AKT signaling pathway may be associated with the differentiation of bFGF and NGF treated DPSCs. Our date provided theoretical basis for DPSCs to treat neurological diseases and repair neuronal damage.