bFGF促增殖后骨髓间充质干细胞向多巴胺能神经元样细胞的分化

目的探讨碱性成纤维细胞生长因子(Basic fibroblast growth factor,bFGF)体外作用于骨髓间充质干细胞(Mesen-chymal stem cells,MSCs)后,诱导其向神经元样细胞和多巴胺能神经元样细胞定向分化的情况。方法从鼠骨髓中获得MSCs,培养传代,用MTT法检测bFGF对骨髓MSCs生长的影响。10 ng/ml bFGF作用2 d后,通过IBMX、细胞因子bFGF、GDNFI、L-1β、中脑神经胶质细胞条件培养基和中脑神经细胞膜碎片等分组联合诱导骨髓MSCs向神经元样细胞、多巴胺能神经元样细胞分化,免疫细胞化学方法鉴定特异标志NSE、MAP-2a,b和TH的表达。结果在一定范围内,bFGF对骨髓MSCs具有明显的促增殖作用。分化的神经元样细胞表达NSE、MAP-2a,b和TH,联合应用GDNFI、L-1β、中脑条件培养基和中脑神经细胞膜碎片诱导7 d后,NSE阳性率为(27.774±2.747)%,MAP-2a,b为(28.006±3.080)%,TH为(3.098±0.352)%。结论体外骨髓MSCs被诱导分化成神经元样细胞和多巴胺能神经元样细胞,为帕金森等中枢神经系统疾病的细胞移植治疗奠定了基础。     

骨髓基质干细胞诱导分化滑膜样细胞移植预防屈肌腱粘连的实验研究

目的探讨移植的骨髓基质干细胞诱导分化的滑膜样细胞是否具有明显的防止屈肌腱粘连的功效。方法提取兔骨髓基质干细胞诱导下分化为滑膜样细胞。经鉴定后,将滑膜样细胞移植于大白兔损伤的跟腱处,术后l、2、4、8周取材,进行大体标本粘连等级评定、生物力学测试及组织学观察。结果对分化的滑膜样细胞鉴定,光镜下、电镜下均符合滑膜细胞结构特征,免疫组化Vimentin阳性,CD68阴性,符合成纤维细胞样滑膜细胞(B型滑膜细胞)的特征。滑膜样细胞移植术后,光镜及扫描电镜发现肌腱表面光滑,被覆大量滑膜样细胞。同一时相点实验组同对照组相比粘连明显减轻(P<0.05)。结论骨髓基质干细胞在一定条件下可以诱导分化为滑膜样细胞。滑膜样细胞移植可以有效的防止肌腱粘连。     

大鼠骨髓间充质干细胞向肝样细胞的定向诱导分化

目的 探讨肝细胞生长因子(Hepatocyte growth factor,HGF)和碱性成纤维细胞生长因子(Basic fibroblast growthfactor,bFGF)诱导大鼠骨髓间充质干细胞(Bone marrow mesenchymal stem cells,BM-MSCs)分化为肝样细胞的可行性。方法取SD大鼠股骨骨髓,直接贴壁法分离纯化BM-MSCs,并体外传代,流式细胞术和成骨诱导对其进行鉴定。取第3代BM-MSCs,分为2组:实验组用HGF(20 ng/ml)和bFGF(10 ng/ml)进行诱导,阴性对照组不加诱导剂,倒置显微镜下观察细胞形态变化;RT-PCR法检测诱导后细胞甲胎蛋白(Alpha fetoprotein,AFP)和白蛋白(Albumin,ALB)基因mRNA的转录水平;免疫细胞化学染色法检测诱导后细胞的AFP和ALB蛋白的表达。结果第3代BM-MSCs表型标志和功能特性均符合MSCs的特点。BM-MSCs经HGF和bFGF诱导后呈肝样细胞形态。实验组细胞可检测出AFP和ALB基因mRNA的表达。实验组细胞诱导后第7天,AFP蛋白开始表达,第14天时表达降低,第21天时不表达;ALB于诱导后第14天出现表达,并随诱导时间的延长表达逐渐增加。结论 HGF和bFGF具有体外诱导BM-MSCs向肝样细胞分化的作用。     

骨髓间充质干细胞向视网膜神经节样细胞的分化

目的探讨乳鼠视网膜细胞条件分化液诱导骨髓间充质干细胞(BMSCs)的神经分化情况,以期为视网膜退行性疾病提供治疗方案。方法体外分离培养Wistar大鼠乳鼠BMSCs,观察BMSCs的增殖情况并进行鉴定;制备乳鼠视网膜细胞条件分化液,以其诱导BMSCs,观察BMSCs的神经分化情况,并行免疫组化鉴定。结果体外培养获得了较纯的BMSCs;在乳鼠视网膜细胞条件分化液的环境中,诱导后72h,BMSCs胞体收缩成锥形或球形,细胞突起变细、变长,呈神经细胞的典型形态;免疫组化结果显示,部分细胞呈神经元特异性烯醇化酶(NSE)、巢蛋白(nestin)和Thy1.1阳性反应。结论乳鼠视网膜细胞条件分化液可诱导BMSCs分化成视网膜神经节样细胞。     

骨髓基质干细胞对大鼠肝纤维化细胞凋亡的影响

目的探讨骨髓基质干细胞(BMSCs)对大鼠肝纤维化细胞(CFSCs)凋亡的影响。方法常规培养BMSCs、CFSCs和大鼠肝细胞系BRL,并双层共培养CFSCs与BMSCs。用ELISA方法检测BMSCs培养上清中NGF、HGF和TGF-β1的浓度;RT-PCR检测与BMSCs共培养的CFSCs及BRL的p75表达;TUNEL法检测BMSCs分泌的细胞因子封闭后对CFSCs凋亡的影响。结果BMSCs可分泌NGF、HGF、TGF-β1等细胞因子,且随着培养时间的延长,其分泌量逐渐增多;BRL不表达p75,CFSCs表达p75,且与BMSCs共培养后,其表达量增高;分别用p75的阻断剂TAT-Pep5、HGF的中和抗体和JNK的阻滞剂sp600125作用后,BMSCs诱导CFSCs凋亡的比例均明显降低;封闭TGF-β1后,BMSCs诱导CFSCs凋亡的比例增高。结论BMSCs能够通过分泌NGF和HGF促进CFSCs的凋亡,这种凋亡诱导作用依赖于JNK的活性,并且在封闭TGF-β1后增强。     

白藜芦醇诱导Raji细胞死亡的自噬途径

目的探讨白藜芦醇对Burkitt B淋巴瘤Raji细胞的增殖抑制作用及诱导死亡途径。方法用白藜芦醇处理Raji细胞,透射电镜及MDC染色检测细胞死亡;Western blot法检测Caspase-3、细胞色素c及CathepsinD蛋白的表达。结果白藜芦醇可明显抑制Raji细胞增殖,电镜观察细胞内出现了大量的自噬小泡,MDC染色后细胞点块状荧光结构明显增加。Western blot分析显示,白藜芦醇可引起细胞色素c从线粒体释放,但释放量与Jurkat细胞相比明显减少,且不能导致Caspase-3的活化。Cathepsin D活性成分32kD片段随白藜芦醇处理时间的延长而减少。结论白藜芦醇可抑制Raji细胞增殖,并通过Caspase非依赖途径诱导细胞自噬死亡。     

白藜芦醇诱导人皮肤鳞状细胞癌凋亡的蛋白质组学研究

为了探讨白藜芦醇抗皮肤鳞状细胞癌生物效应和分子机制,采用MTT法测定细胞活性,细胞流式法检测细胞凋亡率;SILAC蛋白质组学方法鉴定白藜芦醇调控的蛋白质分子。白藜芦醇呈浓度依赖性抑制皮肤鳞状细胞癌细胞的活性,细胞的存活率从100%降为56.7%;50μg/mL白藜芦醇处理导致37.3%细胞发生凋亡;鉴定了11个受白藜芦醇调控的蛋白质分子,其中BAG1,PDCD11,BCLAF1,HSPA9,YWHAZ等5个细胞凋亡相关蛋白被发现受白藜芦醇调控。     

大鼠骨髓间充质干细胞体外向血管平滑肌样细胞诱导分化过程中Periostin的表达及其作用

目的探讨血小板源性生长因子(Platelet derived growth factor,PDGF)-BB诱导骨髓间充质干细胞(Bone marrow-derived mesenchymal stem cells,BMSCs)向血管平滑肌样细胞(Vascular smooth muscle-like cells,VSMLCs)分化过程中Periostin的表达及其在促VSMLCs分化中的作用。方法采用全骨髓贴壁培养法分离和培养大鼠BMSCs,取第2代BMSCs分为2组:诱导Ⅰ组(用50 ng/ml PDGF-BB单独向VSMLCs诱导)和诱导Ⅱ组(加入地塞米松1μmol/L、胰岛素1μmol/L、吲哚美辛1μmol/L、3-异丁基-1甲基黄嘌呤0.5 mmol/L,向脂肪样细胞诱导),以大鼠胸大动脉平滑肌细胞作为阳性对照。分别于诱导后7 d和14 d,采用RT-PCR检测细胞中平滑肌肌动蛋白(SMα-actin)、平滑肌肌球蛋白重链(SM MHC)、平滑肌肌钙结合蛋白(SM Calponin)和Periostin mRNA的转录水平,Western blot检测Periostin蛋白的表达水平。结果诱导Ⅰ组细胞的SMα-actin、SM MHC、SMCalponin和Periostin基因mRNA及Periostin蛋白的表达水平14 d比7 d显著增强,且差异有统计学意义(P<0.05);14 d与阳性细胞相比,差异无统计学意义(P>0.05);未诱导组及诱导Ⅱ组在14 d均无表达。结论 PDGF-BB(50 ng/ml)能够单独诱导BMSCs向VSMCs分化,Periostin在此过程中起重要作用。     

兔骨髓基质干细胞的分离培养及鉴定

目的探讨兔骨髓基质干细胞(MSC)体外分离培养及鉴定。方法自兔髂骨抽取骨髓,采用密度梯度离心法分离纯化出MSC,并增殖。观察MSC的生长情况及形态学特点,流式细胞仪检测第3代MSC表面抗原的表达情况。结果体外培养的兔MSC贴壁生长,呈长梭形,可增殖形成克隆;MSC阳性表达CD29,CD90,但CD34,CD45呈阴性。结论利用密度梯度离心法获取的MSC具有大量增殖的能力,表达CD29,CD90,不表达CD34,CD45。     

大鼠骨髓间充质干细胞的体外分离培养与鉴定

目的建立大鼠骨髓间充质干细胞(Mesenchymal stem cells,MSCs)体外分离培养及鉴定的方法 ,为MSCs的系列研究奠定基础。方法采用全骨髓直接贴壁筛选法分离培养MSCs并传代,倒置相差显微镜下观察细胞形态,以MTT法检测细胞增殖水平并绘制生长曲线。取第3代MSCs,流式细胞术检测细胞周期和细胞表型,应用成骨细胞诱导液和脂肪样细胞诱导液诱导MSCs定向分化,鉴定其分化能力。结果全骨髓细胞培养5d,镜下可见贴壁细胞增殖明显,细胞形态较均一,大部分呈梭形,7d左右可传代,经2～3次传代后细胞呈单一梭形的成纤维样细胞,即MSCs;细胞生长曲线呈S形;经流式细胞仪检测,MSCs细胞76.01%处于G0/G1期,7.13%处于G2/M期,16.86%处于S期;MSCs表面不表达CD34;在特定诱导液作用下,MSCs可分别向成骨样细胞及脂肪样细胞分化。结论已成功建立了分离培养及鉴定MSCs的方法 ,可用来评价体外培养的MSCs。     

白藜芦醇对脓毒症大鼠急性肺损伤的保护作用及对巨噬细胞炎症蛋白-2、IL-10、IL-18表达的影响

目的研究白藜芦醇(Resveratrol,Res)对脓毒症大鼠急性肺损伤(Acute lung injury,ALI)的保护作用及对ALI大鼠肺组织中巨噬细胞炎症蛋白-2(Macrophage inflammatory protein,MIP-2)、白细胞介素-10(Interleukin-10,IL-10)和白细胞介素-18(Interleukin-18,IL-18)表达的影响。方法将SD大鼠随机分为空白对照组(Con组)、假手术组(Sham组)、脓毒症组(Sep组)和白藜芦醇组(Res组)。采用盲肠结扎穿刺术(Cecal ligation and puncture,CLP)制备脓毒症相关性ALI大鼠模型,造模24 h后,Res组给予0.3 ml/100 g的Res液,Con、Sham和Sep组给予等量生理盐水,均经尾静脉注射。各组分别于0、6、12、24和48 h,取大鼠肺组织,HE染色观察病理形态学变化,计算肺湿重/干重比值(W/D);ELISA法检测各组大鼠血浆中MIP-2、IL-10和IL-18含量;Western blot法检测各组大鼠肺组织中MIP-2、IL-10和IL-18蛋白的表达水平。结果 Res组在造模后12 h,肺组织病理变化与Sep组相比有所减轻,48 h Res作用达到最强,各种病理改变明显减轻,部分肺组织开始接近正常形态;肺组织W/D比值与Sep组相比均明显降低(P<0.05);Res组在12、24和48 h MIP-2水平均明显低于同时间点Sep组(P<0.05),在24和48 h IL-10水平明显低于同时间点Sep组(P<0.05),12、24和48 h IL-18水平明显低于同时间点Sep组(P<0.05)。Western blot结果显示,造模后24 h,Res组MIP-2、IL-10和IL-18蛋白表达水平明显低于Sep组(P<0.05)。结论白藜芦醇能有效减轻脓毒症所致ALI,作用与抑制MIP-2、IL-10和IL-18的过度表达,实现内稳态有关。     

Stabilization of resveratrol immobilized in monodisperse cyano-functionalized porous polymeric microspheres

To preserve the high anti-oxidant activity of resveratrol for a long period of time, porous particles were utilized. The porosity of these substrate particles was controlled by DVB content and toluene/heptane ratios in the seeded polymerization. The influence of porosity on the anti-oxidant activity of the immobilized resveratrol was investigated. From SEM and CLSM analysis, it was confirmed that the resveratrol was stabilized in the porous particles after the immobilization process. The resveratrol has a crystalline structure, which was maintained even after immobilization; however, the resveratrol exhibited an amorphous form in the case of the smallest pore size and the highest specific surface area. Although the loading capacity of resveratrol was largely affected by the hydrophobicity and the specific surface area of porous particles, the anti-oxidant activity of immobilized resveratrol was preserved in over 93% in comparison to the raw resveratrol. In addition, the bioactivity of resveratrol immobilized in the porous particles was sustained for 5 weeks.     

Separation and purification of resveratrol from Polygonum cuspidatum by macroporous adsorption resin mixed-bed techology

ABSTRACT

This work is focused on separation and purification of resveratrol from Polygonum cuspidatum by macroporous adsorption resin (MAR) mixed-bed technology. Firstly, the optimal MAR mixed-bed was obtained according to the adsorption and desorption performance of 32 kinds of MAR. Then, operation conditions of adsorption and desorption were investigated and optimized, and optimal operation conditions were obtained. Under optimal conditions, the adsorption capacity and adsorption ratio arrived at 23.89 mg g^?1 and 98.53% separately, while the desorption ratio and purity would be 82.05% and 19.32%. The purity was increased by 5 times in the crude extraction after an adsorption/desorption circle. Finally, the adsorption kinetics and thermodynamics were discussed.     

Density-Dependent Differentiation of Tonsil-Derived Mesenchymal Stem Cells into Parathyroid-Hormone-Releasing Cells

Mesenchymal stem cells (MSCs) can differentiate into endoderm lineages, especially parathyroid-hormone (PTH)-releasing cells. We have previously reported that tonsil-derived MSC (T-MSC) can differentiate into PTH-releasing cells (T-MSC-PTHCs), which restored the parathyroid functions in parathyroidectomy (PTX) rats. In this study, we demonstrate quality optimization by standardizing the differentiation rate for a better clinical application of T-MSC-PTHCs to overcome donor-dependent variation of T-MSCs. Quantitation results of PTH mRNA copy number in the differentiated cells and the PTH concentration in the conditioned medium confirmed that the differentiation efficiency largely varied depending on the cells from each donor. In addition, the differentiation rate of the cells from all the donors greatly improved when differentiation was started at a high cell density (100% confluence). The large-scale expression profiling of T-MSC-PTHCs by RNA sequencing indicated that those genes involved in exiting the differentiation and the cell cycle were the major pathways for the differentiation of T-MSC-PTHCs. Furthermore, the implantation of the T-MSC-PTHCs, which were differentiated at a high cell density embedded in hyaluronic acid, resulted in a higher serum PTH in the PTX model. This standardized efficiency of differentiation into PTHC was achieved by initiating differentiation at a high cell density. Our findings provide a potential solution to overcome the limitations due to donor-dependent variation by establishing a standardized differentiation protocol for the clinical application of T-MSC therapy in treating hypoparathyroidism.     

Dietary induced alterations in the fatty acids of rat bone marrow

Weanling rats were fed fat free diets supplemented with 10% added fatty acids so that dietary effects on bone marrow fatty acids could be determined. The addition or deletion of linoleic acid from the fatty acid supplement resulted in alterations of the fatty acid patterns of bone marrow lipids but to a lesser degree than in erythrocyte lipids. With myristic acid supplementation, increased amounts of stearic acid were found in the lipid fractions, the difference between the bone marrow and erythrocyte lipids being less marked than when linoleic acid was fed. The activities of the bone marrow lipases varied with the dietary treatment. When linoleic acid was fed, higher rates of hydrolysis were observed with saturated fatty acid substrates. The reverse occurred when saturated fatty acids were fed.     

Effect of essential and nonessential amino acid compositions on the in vitro behavior of human mesenchymal stem cells

Mesenchymal stem cells (MSCs) from bone marrow appear to be an attractive tool for use in tissue engineering and cell-based therapies due to their multipotent capacity. The majority of studies on MSCs have been restricted to the roles of growth factors, cytokines, and hormones. Based on previous reports demonstrating the important roles of amino acids, we sought to evaluate the effect of essential amino acids (EAs) and nonessential amino acids (NEAs) on the proliferation and differentiation of MSCs. The results showed that the EA/NEA compositions during culture could significantly modulate MSC proliferation and differentiation and, especially, that EAs served as a potent positive modulator in the proliferation of MSCs without causing a deficit in the differentiation capacity of the cells. These results will be very useful in the production of MSC-based cell therapy products for use in the field of tissue engineering and regenerative medicine.     

非灌流法分离大鼠肝星形细胞及其鉴定

目的采用非灌流法分离大鼠肝星形细胞(Hepatic stellate cell,HSC),并进行鉴定。方法采用非灌流法结合酶消化法分离大鼠肝脏细胞,密度梯度离心进一步分离HSC,油红染色检测HSC胞质中的脂滴,免疫组化法检测细胞中α-平滑肌肌动蛋白(α-Smooth muscle actin,α-SMA)、结蛋白(Desmin)及神经胶质酸性蛋白(Glial fibrillary acidic protein,GFAP)的表达。结果非灌流法结合酶消化法可成功分离大鼠HSC;密度梯度离心纯化的HSC经油红染色,细胞核周围可见红色脂滴;该细胞中α-SMA、结蛋白及GFAP的免疫组化染色结果均呈阳性,细胞着色率可达90%以上。结论成功建立了大鼠HSC的非灌流分离模式,所获得的HSC纯度较高,该方法稳定简便,具有一定的推广应用价值。     

诱导性多能干细胞免疫原性的研究进展

2006年,研究人员将一系列转录因子导入小鼠成纤维细胞中,诱导出了一种类似于胚胎干细胞状态的细胞,称为"诱导性多能干细胞"(induced pluripotent stem cell,简称iPS细胞)。iPS细胞在具有高度自我更新和分化能力的同时,进一步避免了传统胚胎干细胞的伦理学问题,特别是该技术使干细胞自体化移植更易实现,在很大程度上推进了干细胞技术的临床应用。目前,在iPS细胞的诱导方式和诱导效率方面,已取得了较大进展,但在iPS细胞的诱导过程以及再分化过程中,细胞针对于自体的免疫原性是否发生改变,目前尚不明确。本文就近年来iPS细胞免疫原性的研究进展作一简要综述。