Anti-osteoarthritis effect of a combination treatment with human adipose tissue-derived mesenchymal stem cells and thrombospondin 2 in rabbits

BACKGROUND Osteoarthritis(OA),a chronic age-related disease characterized by the slowly progressive destruction of articular cartilage,is one of the leading causes of disability.As a new strategy for treatment of OA,mesenchymal stem cells(MSCs)have the potential for articular cartilage regeneration.Meanwhile,thrombospondin 2(TSP2)promotes the chondrogenic differentiation of MSCs.AIM To investigate whether TSP2 induces chondrogenic differentiation of human adipose-derived MSCs(hADMSCs)and potentiates the therapeutic effects of hADMSCs in OA rabbits.METHODS We investigated the chondrogenic potential of TSP2 in hADMSCs by analyzing the expression of chondrogenic markers as well as NOTCH signaling genes in normal and TSP2 small interfering RNA(siRNA)-treated stem cells.Anterior cruciate ligament transection surgery was performed in male New Zealand white rabbits,and 8 wk later,hADMSCs(1.7×10^6 or 1.7×10^7 cells)were injected into the injured knees alone or in combination with intra-articular injection of TSP2(100 ng/knee)at 2-d intervals.OA progression was monitored by gross,radiological,and histological examinations.RESULTS In hADMSC culture,treatment with TSP2 increased the expression of chondrogenic markers(SOX9 and collagen Ⅱ)as well as NOTCH signaling genes(JAGGED1 and NOTCH3),which were inhibited by TSP2 siRNA treatment.In vivo,OA rabbits treated with hADMSCs or TSP2 alone exhibited lower degree of cartilage degeneration,osteophyte formation,and extracellular matrix loss 8 wk after cell transplantation.Notably,such cartilage damage was further alleviated by the combination of hADMSCs and TSP2.In addition,synovial inflammatory cytokines,especially tumor-necrosis factor-α,markedly decreased following the combination treatment.CONCLUSION The results indicate that TSP2 enhances chondrogenic differentiation of hADMSCs via JAGGED1/NOTCH3 signaling,and that combination therapy with hADMSCs and TSP2 exerts synergistic effects in the cartilage regeneration of OA joints.

Differentiation of human adipose-derived stem cells into neuron-like cells by Radix Angelicae Sinensis

Human adipose tissues are an ideal source of stem cells. It is important to find inducers that can safely and effectively differentiate stem cells into functional neurons for clinical use. In this study, we investigate the use of Radix Angelicae Sinensis as an inducer of neuronal differentiation. Primary human adipose-derived stem cells were obtained from adult subcutaneous fatty tissue, then pre-induced with 10% Radix Angelicae Sinensis injection for 24 hours, and incubated in serum-free Dulbecco＇s modified Eagle＇s medium/Nutrient Mixture F-12 containing 40% Radix Angelicae Sinensis to induce its differentiation into neuron-like cells. Butylated hydroxyanisole, a common in- ducer for neuronal differentiation, was used as the control. After human adipose-derived stem cells differentiated into neuron-like cells under the induction of Radix Angelicae Sinensis for 24 hours, the positive expression of neuron-specific enolase was lower than that of the butylated hydroxyani- sole-induced group, and the expression of glial fibrillary acidic protein was negative. Alter they were induced for 48 hours, the positive expression of neuron specific enolase in human adipose-derived stem cells was significantly higher than that of the butylated hydroxyanisole-induced group. Our experimental findings indicate that Radix Angelicae Sinensis can induce human adipose-derived stem cell differentiation into neuron-like cells and produce less cytotoxicity.

In vivo tracking of human adipose-derived stem cells labeled with ferumoxytol in rats with middle cerebral artery occlusion by magnetic resonance imaging

Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except I day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem ceils compared with T2-weighted imaging in routine MRI.

Ameliorative effects of human adipose tissue-derived mesenchymal stem cells on myelin basic protein-induced experimental autoimmune encephalomyelitis in Lewis rats

Mesenchymal stem cells have been previously shown to exert an immunomodulatory function. The present study sought to investigate the effects of multipotential human adipose tissue-derived mesenchymal stem cells （hAdMSCs） on disease progression and cytokine expression in Lewis rats with experimental autoimmune encephalomyelitis （EAE） induced by myelin basic protein. The duration of EAE paralysis in the group treated on day 7 posfimmunization with 5 × 10^6 hAdMSCs was significantly reduced compared with the vehicle-treated controls and the 1 x 106 hAdMSC- treated group. The duration of EAE paralysis in the groups treated with 5 × 10^6 hAdMSCs on both day 1 and day 7 postimmunization was significantly reduced compared with the vehicle-treated controls and the groups treated with 5 × 10^6 hAdMSCs on both day 7 and day 10 postimmunization. The mRNA expression of interleukin-10 and indoleamine 2, 3-dioxygenase was significantly decreased in the hAdMSC-treated group compared with the vehicle-treated group. These findings suggest that the ameliorative effects of hAdMSCs on EAE symptoms operate in a dose- and time-dependent manner and can be mediated in part by the ample production of anti-inflammatory cytokines.

Human adipose tissue-derived stem cells in breast reconstruction following surgery for cancer: A controversial issue

Breast cancer is the most common cancer in women. Patients, in particular young women, after surgical removal of the tumor have a poorer quality of life and psychological problems. Plastic surgery procedures for breast reconstruction, including autologous fat grafting, concur to reduce cosmetic and psychological problems. The maintenance of the transplanted fat is partially due to the presence of resident adipose derived-stem cells (ASCs). The latter can be isolated by digestion and centrifugation from the stromal vascular fraction (SVF) of subcutaneous adipose tissue. Intraoperatory SVF/ASC enrichment has been proposed to stabilize and optimalize autologous fat engraftment for breast reconstructive surgery after mastectomy, but the safety of these procedures is still uncertain. Although the literature offers contrasting opinions concerning the effects of ASCs on cancer growth according to the tumor type, at the present time ASC implementation for regenerative medicine therapies should be carefully considered in patients previously treated for breast cancer. At the present, reconstructive therapy utilizing ASC-enriched fat grafting should be postponed until there is no evidence of active disease.

Long-term phenotypic characterization of human bone marrow and adipose tissue derived mesenchymal stromal cells

We present methods to characterize mesenchymal stromal cells (MSC) over long time periods in vitro. The methods entail passaging cells multiple times and performing differentiation studies with the cells at each passage. Using an array of surface markers and flow cytometric quantification, the data can be correlated to traditional measures of differentiation such as PCR and staining. Using these methods to quantify the amount of differentiation, we concluded that many common MSC markers do not specifically define MSCs with true stem cell properties. Additionally, adipose-derived as opposed to bone marrow-derived MSCs show long-term CD34+ labeling. The methods described can be used to help identify stem cell markers and to characterize the state of stem cells in vitro. Compiling these data from multiple laboratories would be helpful to determine source, extraction and culture methods needed to obtain high yields of useful stem cells.

Ultrastructure of neuronal-like cells differentiated from adult adipose-derived stromal cells

β-mercaptoethanol induces in vitro adult adipose-derived stromal cells （ADSCs） to differentiate into neurons. However, the ultrastructural features of the differentiated neuronal-like cells remain unknown. In the present study, inverted phase contrast microscopy was utilized to observe β-mercaptoethanol-induced differentiation of neuronal-like cells from human ADSCs, and immunocytochemistry and real-time polymerase chain reaction were employed to detect expression of a neural stem cells marker （nestin）, a neuronal marker （neuron-specific enolase）, and a glial marker （glial fibrillary acidic protein）. In addition, ultrastructure of neuronal-like cells was observed by transmission election microscopy. Results revealed highest expression rate of nestin and neuron-specific enolase at 3 and 5 hours following induced differentiation; cells in the 5-hour induction group exhibited a neuronal-specific structure, i.e., Nissl bodies. However, when induction solution was replaced by complete culture medium after 8-hour induction, the differentiated cells reverted to the fibroblast-like morphology from day 1. These results demonstrate that β-mercaptoethanol-induced ADSCs induced differentiation into neural stem cells, followed by morphology of neuronal-like cells. However, this differentiation state was not stable.

Human pluripotent stem cells:Towards therapeutic development for the treatment of lifestyle diseases

There are two types of human pluripotent stem cells: Embryonic stem cells(ESCs) and induced pluripotent stem cells(iPSCs),both of which launched themselves on clinical trials after having taken measures to overcome problems: Blocking rejections by immunosuppressants regarding ESCs and minimizing the risk of tumorigenicity by depleting exogenous gene components regarding iP SCs.It is generally assumed that clinical applications of human pluripotent stem cells should be limited to those cases where there are no alternative measures for treatments because of the risk in transplanting those cells to living bodies.Regarding lifestyle diseases,we have already several therapeutic options,and thus,development of human pluripotent stem cell-based therapeutics tends to be avoided.Nevertheless,human pluripotent stem cells can contribute to the development of new therapeutics in this field.As we will show,there is a case where only a short-term presence of human pluripotent stem-derived cells can exert long-term therapeutic effects even after they are rejected.In those cases,immunologically rejections of ESC-or allogenic iP SC-derived cells may produce beneficial outcomes by nullifying the risk of tumorigenesis without deterioration of therapeutic effects.Another utility of human pluripotent stem cells is the provision of an innovative tool for drug discovery that are otherwise unavailable.For example,clinical specimens of human classical brown adipocytes(BAs),which has been attracting a great deal of attention as a new target of drug discovery for the treatment of metabolic disorders,are unobtainable from living individuals due to scarcity,fragility and ethical problems.However,BA can easily be produced from human pluripotent stem cells.In this review,we will contemplate potential contribution of human pluripotent stem cells to therapeutic development for lifestyle diseases.

Effects of Human Insulin Gene Transfection on the Adipogenic Differentiation of Human Umbilical Cord Mesenchymal Stem Cells in Silk Fibroin Scaffolds <i>in Vitro</i>

The resorption of the transplanted fat over time limited the use of autologous fat for the reconstruction of soft tissue defect. Tissue engineering (TE) adipose with silk fibroin scaffold could be a promising substitute for soft tissue filling. In this study, we try to develop a tissue engineering adipose in vitro by seeding silk fibroin scaffold with human umbilical cord mesenchymal stem cells (hUCMSCs) after transfected with recombinant human insulin gene lentivirus. Our aim was to observe the effects of the insulin gene transfection on the adipogenesis of hUCMSCs when cultured with silk fibroin scaffolds. The hUCMSCs infected with recombinant lentiviral pLenti6.3-insulin-IRES-EGFP were seeded on silk fibroin scaffolds and cultured in adipogenic differentiation medium for 5 - 7 days. The expression of adipogenic gene PPARγ-2 was tested by RT-PCR after 7 days culture of adipogenic induction. The accumulation of cytoplasmic droplets of neutral lipids was assessed by Oil Red O staining. The RNA and protein expression of transfected insulin gene in hUCMSCs were detected by QPCR and western blot. The effect of recombinant lentivirus transfection on the growth and proliferation of hUCMSCs was observed by MTT test. We observed that the 2-ΔΔCt value of insulin gene expression of hUCMSCs in the transfected group was 300.25 times higher than that in the untransfected group. The western blot showed that a positive band was discerned at the site of a relative molecular mass of 8 × 103 Dalton in transfected group. After adipogenic culture for 7 days, under the fluorescent inverted phase-contrast microscope, after Oil Red O staining, a lot of adipocytes appeared in silk fibroin scaffold;round adipose droplets showed intracellularly;the size of the adipocytes was not homogenous, and the density of adipocytes in transfected group was significantly higher than that in untransfected group (P = 0.007, P < 0.01). RT-PCR results showed that the expression of adipogenic gene PPARγ-2 in transfected group was much stronger than that in untransfected group. MTT test showed that there was no significant difference in optical density (A) at each time point between transfected group and nontransfected group (P = 0.056, P > 0.05). And there was also no significant difference in optical density (A) between cell group and cell-scalffold group (P = 0.066, P > 0.05). We concluded that insulin gene could obviously promote the adipogenic differentiation of hUCMSCs, and a tissue engineering adipose could be constructed by the silk fibroin scaffolds seeded with human insulin gene-modified hUCMSCs effectively in vitro.

Insulin producing cells established using non-integrated lentiviral vector harboring PDX1 gene

AIM: To investigate reprogramming of human adipose tissue derived stem cells into insulin producing cells using non-integrated lentivirus harboring PDX1 gene.METHODS: In this study, human adipose tissue derived stem cells(hADSCs) were obtained from abdominal adipose tissues by liposuction, selected by plastic adhesion, and characterized by flow cytometric analysis.Human ADSCs were differentiated into adipocytes and osteocytes using differentiating medium to confirm their multipotency. Non-integrated lentiviruses harboring PDX1(Non-integrated LV-PDX1) were constructed using specific plasmids(pLV-HELP, pMD2G, LV-105-PDX1-1).Then, hADSCs were transduced with non-integrated LVPDX1. After transduction, ADSCsPDX1+were cultured in high glucose DMEM medium supplement by B27, nicotinamide and βFGF for 21 d. Expressions of PDX1 andinsulin were detected at protein level by immunofluorescence analysis. Expressions of PDX1, neurogenin3(Ngn3), glucagon, glucose transporter2(Glut2) and somatostatin as specific marker genes were investigated at mRNA level by quantitative RT-PCR. Insulin secretion of hADSCsPDX1+in the high-glucose medium was detected by electrochemiluminescence test. Human ADSCsPDX1+were implanted into hyperglycemic rats.RESULTS: Human ADSCs exhibited their fibroblast-like morphology and made colonies after 7-10 d of culture.Determination of hADSCs identified by FACS analysis showed that hADSCs were positive for mesenchymal cell markers and negative for hematopoietic cell markers that guaranteed the lack of hematopoietic contamination. In vitro differentiation of hADSCs into osteocytes and adipocytes were detected by Alizarin red and Oil red O staining and confirmed their multilineage differentiation ability. Transduced hADSCs+PDX1became round and clusters in the differentiation medium. The appropriate expression of PDX1 and insulin proteins was confirmed using immunocytochemistry analysis.Significant expressions of PDX1, Ngn3, glucagon, Glut2and somatostatin were detected by quantitative RTPCR. hADSCsPDX1+revealed the glucose sensing ability by expressing Glut2 when they were cultured in the medium containing high glucose concentration. The insulin secretion of hADSCsPDX1+in the high glucose medium was 2.32 μU/mL. hADSCsPDX1+implantation into hyperglycemic rats cured it two days after injection by reducing blood glucose levels from 485 mg/dL to the normal level.CONCLUSION: Human ADSCs can differentiate into IPCs by non-integrated LV-PDX1 transduction and have the potential to be used as a resource in type 1 diabetes cell therapy.

miR-205促进hASCs细胞系向软骨细胞方向分化的作用及机制研究

目的探讨微小RNA(miR)-205通过调控核心结合因子α-1(Cbfα-1)表达促进人脂肪干细胞(hASCs)细胞系向软骨细胞方向分化的作用及机制。方法慢病毒转染法将Lenti-miR-205、Lenti-control慢病毒液分别转染至hASCs细胞,命名为miR-205过表达组、miR-NC组,另取未处理细胞为对照组;RT-qPCR法检测转染后miR-205基因表达量,MTT比色法检测细胞增殖;用甲苯胺蓝染色、免疫细胞染色及免疫荧光染色观察转染后第3代hASCs细胞诱导分化情况,RT-qPCR、Western blot法检测诱导分化2周后各组Cbfα-1、Smad3、TGF-β1、ColⅡmRNA和蛋白表达。结果转染后miR-205过表达组miR-205基因相对表达量高于miR-NC组和对照组(P<0.001)。miR-205过表达组转染后hASCs细胞培养3、7 d MTT试验吸光度(A)值高于对照组和miR-NC组(P<0.05)。诱导分化2周后,甲苯胺蓝染色显示,miR-205过表达组细胞染色呈强阳性深蓝染色,对照组和miR-NC组为微弱浅蓝色;免疫细胞化学染色显示,miR-205过表达组细胞及胞外基质强阳性棕黄染色,对照组和miR-NC组为弱阳性淡黄染色;免疫荧光染色显示,miR-205过表达组红色荧光强度较强,对照组和miR-NC组红色荧光强度较暗淡。miR-205过表达组诱导分化后Cbfα-1 mRNA和蛋白相对表达量低于对照组和miR-NC组,Smad3、TGF-β1、ColⅡmRNA和蛋白相对表达量高于对照组和miR-NC组(P<0.05)。结论miR-205过表达可促进hASCs细胞增殖、促进细胞向软骨细胞方向分化,可能通过抑制Cbfα-1、激活TGF-β1/Smad3信号通路发挥调控作用。

Enzymatic and non-enzymatic isolationsystems for adipose tissue-derived cells:current state of the art

In the past decade, adipose tissue became a highly interesting source of adult stem cells for plastic surgery andregenerative medicine. The isolated stromal vascular fraction (SVF) is a heterogeneous cell population including theadipose-derived stromal/stem cells (ASC), which showed regenerative potential in several clinical studies and trials.SVF should be provided in a safe and reproducible manner in accordance with current good manufacturing practices(cGMP). To ensure highest possible safety for patients, a precisely defined procedure with a high-quality control isrequired. Hence, an increasing number of adipose tissue-derived cell isolation systems have been developed.These systems aim for a closed, sterile, and safe isolation process limiting donor variations, risk for contaminations,and unpredictability of the cell material. To isolate SVF from adipose tissue, enzymes such as collagenase are used.Alternatively, in order to avoid enzymes, isolation systems using physical forces are available. Here, we provide anoverview of known existing enzymatic and non-enzymatic adipose tissue-derived cell isolation systems, which arepatented, published, or already on the market.

Metformin promotes angiogenesis by enhancing VEGFa secretion by adipose-derived stem cells via the autophagy pathway

Human adipose tissue-derived stem cell(ADSC)derivatives are cell-free,with low immunogenicity and no potential tumourigenicity,making them ideal for aiding wound healing.However,variable quality has impeded their clinical application.Metformin(MET)is a 5′adenosine monophosphate-activated protein kinase activator associated with autophagic activation.In this study,we assessed the potential applicability and underlying mechanisms of MET-treated ADSC derivatives in enhancing angiogenesis.We employed various scientific techniques to evaluate the influence of MET on ADSC,assess angiogenesis and autophagy in MET-treated ADSC in vitro,and examine whether MET-treated ADSC increase angiogenesis.We found that low MET concentrations exerted no appreciable effect on ADSC proliferation.However,MET was observed to enhance the angiogenic capacity and autophagy of ADSC.MET-induced autophagy was associated with increased vascular endothelial growth factor A production and release,which contributed to promoting the therapeutic efficacy of ADSC.In vivo experiments confirmed that in contrast to untreated ADSC,MET-treated ADSC promoted angiogenesis.Our findings thus indicate that the application of MET-treated ADSC would be an effective approach to accelerate wound healing by promoting angiogenesis at wound sites.

黑枸杞花青素联合人脂肪源性血管外膜细胞支持脐血造血干/祖细胞的增殖

背景:黑枸杞花青素(Anthocyanins in Lycium ruthenicum Murr,ALRM)是黑枸杞中重要的活性成分之一,具有抗氧化、免疫调节等功效。人脂肪源性血管外膜细胞(CD146^(+)hAD-PCs)是骨髓间充质干细胞的前体细胞,在体外具有促进造血干/祖细胞增殖与分化的功能。ALRM联合CD146^(+)hAD-PCs对脐血造血干/组细胞的体外支持作用有待于研究。目的:探讨ALRM联合CD146^(+)hAD-PCs对脐血CD34^(+)造血干/祖细胞体外扩增的支持作用。方法:CCK-8法检测不同质量浓度ALRM(0,200,400,600,800,1000 mg/L)对CD146^(+)hAD-PCs增殖的影响;流式细胞术检测ALRM对CD146^(+)hAD-PCs细胞周期的影响。共培养实验分为空白组、ALRM组、CD146^(+)hAD-PCs组、ALRM+CD146^(+)hAD-PCs组,分析ALRM联合CD146^(+)hAD-PCs对脐血CD34^(+)造血干/祖细胞的体外支持作用。共培养1,2,4周,比较扩增后细胞数量、集落形成单位数量,流式细胞仪检测细胞免疫表型,ELISA检测细胞因子水平。结果与结论:(1)ALRM质量浓度为200 mg/L时,CD146^(+)hAD-PCs活力最高,CD146^(+)hAD-PCs的G_(0)/G_(1)期细胞比例下降,S期、G_(2)/M期细胞比例上升(P<0.01)。(2)脐血CD34^(+)造血干/祖细胞数量变化:在共培养1,2,4周时ALRM+CD146^(+)hAD-PCs组高于ALRM组(P均<0.05),在共培养2,4周时ALRM+CD146^(+)hAD-PCs组高于CD146^(+)hAD-PCs组(P均<0.05),ALRM组与空白组随着共培养时间延长细胞数量逐渐减少。(3)集落形成能力及免疫表型分析:在共培养1,2周时ALRM+CD146^(+)hAD-PCs组的集落形成单位数量高于CD146^(+)hAD-PCs组和ALRM组(P均<0.05);在共培养1,2,4周时ALRM+CD146^(+)hAD-PCs组CD45^(+)、CD34^(+)CD33^(-)细胞比例高于CD146^(+)hAD-PCs组(P均<0.01)。(4)细胞因子变化:在共培养4周时ALRM+CD146^(+)hAD-PCs组的白细胞介素2水平高于ALRM组、CD146^(+)hAD-PCs组(P<0.05);在共培养2,4周时ALRM+CD146^(+)hAD-PCs组白细胞介素3水平高于CD146^(+)hAD-PCs组(P<0.05);在共培养1周时ALRM+CD146^(+)h AD-PCs组的粒细胞集落刺激因子水平高于CD146^(+)hAD-PCs组,在共培养2周时高于ALRM组、CD146^(+)hAD-PCs组(P<0.01);在共培养1,2,4周时ALRM组、ALRM+CD146^(+)hAD-PCs组的干扰素γ水平低于CD146^(+)hAD-PCs组(P<0.05)。(5)由于空白组无基质细胞,脐血CD34^(+)造血干/祖细胞在共培养1周之后就无法计数,未进行免疫表型、集落分析和细胞因子检测。(6)结果表明:ALRM可以通过促进CD146^(+)hAD-PCs增殖和细胞周期转化进而促进脐血CD34^(+)造血干/祖细胞的体外扩增,在造血干细胞移植研究方面具有重要价值。

泛素特异性蛋白酶42调节人脂肪干细胞成骨向分化

目的:探索泛素特异性蛋白酶42(ubiquitin-specific protease 42,USP42)在人脂肪干细胞(human adipose-derived stem cells,hASCs)体内外成骨向分化中的作用。方法:用慢病毒转染hASCs,构建敲低和过表达USP42的稳定转染细胞系,通过碱性磷酸酶(alkaline phosphatase,ALP)染色及活性定量、茜素红S矿化结节染色及定量,检测实验组(敲低组和过表达组)及对照组在成骨诱导下hASCs成骨向分化能力的差异,通过定量逆转录聚合酶链反应(quantitative reverse transcription polymerase chain reaction,qRT-PCR)检测实验组及对照组成骨相关基因的表达水平,通过蛋白免疫印迹实验检测实验组及对照组成骨相关蛋白的表达水平,通过裸鼠异位成骨实验评价USP42在hASCs体内成骨向分化中的作用。结果:敲低组USP42的mRNA和蛋白表达显著低于对照组,过表达组显著高于对照组。成骨诱导7 d后,敲低组的ALP活性显著高于对照组,过表达组显著低于对照组;成骨诱导14 d后,敲低组茜素红S染色显著深于对照组,过表达组显著浅于对照组。qRT-PCR结果显示,成骨诱导14 d时,敲低组ALP、成骨细胞特异性转录因子(osterix,OSX)和Ⅰ型胶原(collagen typeⅠ,COLⅠ)的mRNA表达水平显著高于对照组,过表达组显著低于对照组。蛋白免疫印迹实验结果显示,成骨诱导14 d时敲低组runt相关转录因子2(runt-related transcription factor 2,RUNX2)、OSX和COLⅠ蛋白表达水平显著高于对照组,过表达组显著低于对照组。裸鼠皮下移植物苏木精-伊红染色结果显示,敲低组类骨组织百分比较对照组显著增高。结论:敲低USP42显著促进hASCs的体内外成骨向分化,过表达USP42显著抑制hASCs的体内成骨向分化,USP42可作为骨组织工程学潜在治疗靶点。

过表达或沉默lncRNA SNHG8的脂肪干细胞对血管内皮细胞功能障碍的影响

目的:研究过表达或沉默长链非编码RNA(lncRNA)SNHG8的脂肪干细胞(ADSCs)对人脐静脉内皮细胞(HUVECs)活力、迁移、成管及表达血管活性因子的影响。方法:(1)流式细胞术及成脂、成骨诱导实验鉴定病态肥胖患者来源的脂肪干细胞(O-ADSCs);RT-qPCR检测健康人群来源的脂肪干细胞(H-ADSCs)及O-ADSCs内lncRNA SNHG8的表达。(2)Transwell建立ADSCs与HUVECs间接共培养48 h体系,设置O-ADSCs+HUVECs组、HADSCs+HUVECs组和HUVECs组,通过RT-qPCR和Western blot检测HUVECs内血管紧张素Ⅱ(AngⅡ)、内皮素1(ET-1)和内皮型一氧化氮合酶(eNOS)的mRNA及蛋白表达水平。(3)进一步构建lncRNA SNHG8过表达或沉默慢病毒并感染O-ADSCs,设置O-ADSCs-OE-SNHG8+HUVECs组、O-ADSCs-OE-NC+HUVECs组、O-ADSCs-sh-SNHG8+HUVECs组和O-ADSCs-sh-NC+HUVECs组,共培养48 h后,通过CCK-8实验、划痕实验和小管形成实验分别检测HUVECs活力、迁移能力和成管能力;RT-qPCR和Western blot检测HUVECs内AngⅡ、ET-1和eNOS的mRNA及蛋白表达水平;硝酸还原酶法检测HUVECs内NO含量。结果:(1)所培养细胞经鉴定符合ADSCs特征;(2)与H-ADSCs比较,lncRNA SNHG8在O-ADSCs中显著高表达(P<0.01);(3)与H-ADSCs+HUVECs和HUVECs组相比,O-ADSCs+HUVECs组中HUVECs内AngⅡ和ET-1的mRNA及蛋白表达水平上调(P<0.01);(4)过表达lncRNA SNHG8的OADSCs可增强HUVECs的活力、迁移能力及成管能力,上调HUVECs中AngⅡ和ET-1的mRNA及蛋白表达水平,下调eNOS的mRNA及蛋白表达水平,减少HUVECs内NO含量(P<0.05);而沉默O-ADSCs中lncRNA SNHG8的表达则呈现相反的结果(P<0.05)。结论:(1)O-ADSCs可通过旁分泌作用增强内皮细胞活力、迁移能力及成管能力;(2)过表达lncRNA SNHG8的O-ADSCs促使内皮细胞分泌舒张-收缩因子失衡,导致血管内皮细胞功能障碍。

三维动静态培养软骨源性微组织的细胞行为及软骨形成能力

背景:与传统二维培养相比,三维培养软骨微组织具有更大的优势,但仍需进一步探索更有利的三维培养方式。目的:评价2种三维培养方式下微组织的细胞行为及促软骨形成能力。方法:通过化学脱细胞方法和组织粉碎方法制备软骨源性微载体,采用DNA定量和核染色验证脱细胞是否成功,通过组织学染色观察脱细胞前后基质保留情况,采用扫描电子显微镜和CCK-8方法对微载体进行表征;通过三维静态培养法和三维动态培养法将软骨源性微载体与人脂肪间充质干细胞结合构建软骨源性微组织,利用扫描电子显微镜、活死染色、RT-qPCR等手段检测两组微组织的细胞活力及成软骨能力。结果与结论:①成功制备软骨源性微载体,与脱细胞前相比,脱细胞后DNA含量显著降低(P<0.001);扫描电子显微镜观察微载体表面有胶原包绕,保持天然软骨细胞外基质特征;CCK-8法检测表明微载体无细胞毒性且能够促进细胞增殖;②扫描电子显微镜及活死染色结果显示,相比三维静态组,三维动态组微组织细胞具有更舒展的形态,细胞与细胞间、细胞与基质间、基质与基质间形成广泛的连接;③RT-qPCR结果表明两组微组织SOX9、蛋白聚糖、Ⅱ型胶原表达在培养7 d或14 d时均增高;14 d时三维动态组各基因相对表达量均显著高于三维静态组(P<0.05);21 d时三维静态组各基因表达均显著高于三维动态组(P<0.001);④结果表明,与三维静态培养微组织相比,三维动态培养微组织可在更短时间实现软骨相关基因的高表达,显示出更好的细胞活性和成软骨能力。

不同转染方式用于modRNA转染人脂肪干细胞的初步研究

目的筛选更优的转染方式,探讨其用于modRNA转染人脂肪干细胞(Human adipose-derived stem cell,hADSC)并表达特定蛋白的可行性。方法分别采用2种电转染方式Optimization4及Optimization6和脂质体转染试剂RNAiMAX,将modGFP转染到hADSC中去。应用流式细胞分析仪和荧光显微镜分析,比较不同转染方式的转染效率和蛋白表达情况;通过细胞死活染色,评估转染后24 h细胞的存活情况;将更优的电转方式与RNAiMAX用于modVEGFA转染hADSC,收集其培养24 h的上清用于人脐静脉内皮细胞(Human umbilical vein endothelial cells,hUVECs)成管和transwell迁移实验,并与基质胶混合后注射于裸鼠皮下,通过大体观、HE染色及免疫荧光染色,分析其在体内促进血管再生的情况。结果Optimization6电转转染hADSC的效率为87.75%±1.52%,高于Optimization4转染组(80.85%±1.48%)和RNAiMAX转染组(81.80%±1.08%),且荧光显微镜观察及流式分析均表明电转染方式的蛋白表达优于RNAiMAX脂质体转染。3种转染方式对细胞的毒性均较小,无统计学差异。与RNAiMAX相比,Optimization6电转能更高效地介导modVEGFA转染hADSC,能更好地促进体外hUVECs成管和迁移,皮下血管再生的效果也更佳。结论相比于RNAiMAX和Optimization4电转染,Optimization6电转方式转染hADSC的效率更高,蛋白表达高效,且能在体内外快速高效促进血管再生。

和厚朴酚抑制人脂肪间充质干细胞增殖

目的 研究厚朴酚对人脂肪间充质干细胞(hADSCs)增殖和凋亡的影响,以此细胞模型初探该药物对肿瘤微环境的影响。方法 用不同浓度的和厚朴酚处理hADSCs,分别采用MTS法和台盼蓝染色法检测细胞的增殖能力,annexin V/PI双染法检测细胞凋亡的改变,qPCR和Western blot检测细胞增殖、凋亡相关基因的mRNA和蛋白质表达,Western blot检测MEK-ERK1/2信号通路中总MEK、磷酸化MEK、总ERK和磷酸化ERK蛋白的表达水平。结果 随着浓度增加,和厚朴酚抑制hADSCs增殖、促进其凋亡的作用显著增强。增殖相关基因CCND1、MKI67和PCNA表达下调,促凋亡相关基因BAX和TP53表达上调,抗凋亡基因BCL2表达下调。和厚朴酚呈浓度依赖性抑制MEK和ERK1/2的磷酸化。结论 和厚朴酚抑制hADSCs增殖,促进其凋亡,作用机制可能与抑制MEK-ERK1/2通路活性有关。

经LED黄光照射的人间充质干细胞旁分泌效应对成纤维细胞光老化的作用研究

目的研究经LED黄光照射的人脂肪间充质干细胞(hADSCs)旁分泌效应对人真皮成纤维细胞(HDFs)光老化的影响。方法利用中波紫外线(UVB)照射HDFs构建光老化模型,并进行细胞增殖、细胞衰老、细胞迁移实验。使用不同能量梯度(2.5、5.0、7.5、10.0 J/cm^(2))LED黄光照射hADSCs进行细胞增殖实验,确定最佳照射能量(10 J/cm^(2))。实验组用LED黄光10 J/cm^(2)照射的hADSCs上清液培养光老化HDFs,对照组用未经照射的hADSCs上清液培养光老化HDFs,用CCK-8法检测2组细胞增殖能力,用β-半乳糖苷酶染色检测2组细胞衰老水平,用微丝绿色荧光探针标记细胞骨架,用流式细胞仪检测细胞活性氧(ROS)含量,并进行转录组测序,对测序发现的显著差异基因进行实时荧光定量聚合酶链反应(qRTPCR)验证、京都基因与基因组百科全书(KEGG)通路富集分析。结果与未照射组比较,UVB照射组HDFs增殖能力下降,衰老细胞(蓝染细胞)明显增多,HDFs迁移受到抑制,差异均有统计学意义(P<0.05)。与对照组比较,经LED黄光照射的hADSCs上清液干预的实验组光老化HDFs增殖能力较强、蓝染细胞较少、细胞形态较为细长、ROS含量较低,差异均有统计学意义(P<0.05)。转录组测序发现6个有意义的差异表达基因:驱动蛋白家族成员20B(KIF20B)、异常纺锤体样小头畸形相关蛋白(ASPM)、A型激酶锚定蛋白9(AKAP9)、着丝粒蛋白F(CENPF)、着丝粒蛋白E(CENPE)、RB1的诱导卷曲蛋白1(RB1CC1)。qRTPCR结果显示,实验组KIF20B、ASPM、AKAP9、CENPF、CENPE、RB1CC1 mRNA表达高于对照组,差异均有统计学意义(P<0.05),与转录组测序结果一致。KEGG通路富集分析显示,显著差异基因富集在长寿调节通路(longevity regulating pathway)。结论经LED黄光照射的hADSCs旁分泌效应对HDFs的光老化具有抑制作用,可能与激活长寿调节通路有关。