|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | | Glial Innate Immunity Generated by Non-Aggregated Alpha-Synuclein in Mouse: Differences between Wild-type and Parkinson's Disease-Linked Mutants. PLoS One. 2010;5(10):e13481 Authors: Roodveldt C, Labrador-Garrido A, Gonzalez-Rey E, Fernandez-Montesinos R, Caro M, Lachaud CC, Waudby CA, Delgado M, Dobson CM, Pozo D BACKGROUND: Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized pathologically by the presence in the brain of intracellular protein inclusions highly enriched in aggregated alpha-synuclein (α-Syn). Although it has been established that progression of the disease is accompanied by sustained activation of microglia, the underlying molecules and factors involved in these immune-triggered mechanisms remain largely unexplored. Lately, accumulating evidence has shown the presence of extracellular α-Syn both in its aggregated and monomeric forms in cerebrospinal fluid and blood plasma. However, the effect of extracellular α-Syn on cellular activation and immune mediators, as well as the impact of familial PD-linked α-Syn mutants on this stimulation, are still largely unknown. METHODS AND FINDINGS: In this work, we have compared the activation profiles of non-aggregated, extracellular wild-type and PD-linked mutant α-Syn variants on primary glial and microglial cell cultures. After stimulation of cells with α-Syn, we measured the release of Th1- and Th2- type cytokines as well as IP-10/CXCL10, RANTES/CCL5, MCP-1/CCL2 and MIP-1α/CCL3 chemokines. Contrary to what had been observed using cell lines or for the case of aggregated α-Syn, we found strong differences in the immune response generated by wild-type α-Syn and the familial PD mutants (A30P, E46K and A53T). CONCLUSIONS: These findings might contribute to explain the differences in the onset and progression of this highly debilitating disease, which could be of value in the development of rational approaches towards effective control of immune responses that are associated with PD. PMID: 21048992 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Dexamethasone treatment induces the reprogramming of pancreatic acinar cells to hepatocytes and ductal cells. PLoS One. 2010;5(10):e13650 Authors: Al-Adsani A, Burke ZD, Eberhard D, Lawrence KL, Shen CN, Rustgi AK, Sakaue H, Farrant JM, Tosh D BACKGROUND: The pancreatic exocrine cell line AR42J-B13 can be reprogrammed to hepatocytes following treatment with dexamethasone. The question arises whether dexamethasone also has the capacity to induce ductal cells as well as hepatocytes. METHODOLOGY/PRINCIPAL FINDINGS: AR42J-B13 cells were treated with and without dexamethasone and analyzed for the expression of pancreatic exocrine, hepatocyte and ductal markers. Addition of dexamethasone inhibited pancreatic amylase expression, induced expression of the hepatocyte marker transferrin as well as markers typical of ductal cells: cytokeratin 7 and 19 and the lectin peanut agglutinin. However, the number of ductal cells was low compared to hepatocytes. The proportion of ductal cells was enhanced by culture with dexamethasone and epidermal growth factor (EGF). We established several features of the mechanism underlying the transdifferentiation of pancreatic exocrine cells to ductal cells. Using a CK19 promoter reporter, we show that a proportion of the ductal cells arise from differentiated pancreatic exocrine-like cells. We also examined whether C/EBPβ (a transcription factor important in the conversion of pancreatic cells to hepatocytes) could alter the conversion from acinar cells to a ductal phenotype. Overexpression of an activated form of C/EBPβ in dexamethasone/EGF-treated cells provoked the expression of hepatocyte markers and inhibited the expression of ductal markers. Conversely, ectopic expression of a dominant-negative form of C/EBPβ, liver inhibitory protein, inhibited hepatocyte formation in dexamethasone-treated cultures and enhanced the ductal phenotype. CONCLUSIONS/SIGNIFICANCE: These results indicate that hepatocytes and ductal cells may be induced from pancreatic exocrine AR42J-B13 cells following treatment with dexamethasone. The conversion from pancreatic to hepatocyte or ductal cells is dependent upon the expression of C/EBPβ. PMID: 21048969 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Stem cell-based therapies for liver diseases: state of the art and new perspectives. Stem Cells Int. 2010;2010:259461 Authors: Piscaglia AC, Campanale M, Gasbarrini A, Gasbarrini G Millions of patients worldwide suffer from end-stage liver pathologies, whose only curative therapy is liver transplantation (OLT). Given the donor organ shortage, alternatives to OLT have been evaluated, including cell therapies. Hepatocyte transplantation has been attempted to cure metabolic liver disorders and end-stage liver diseases. The evaluation of its efficacy is complicated by the shortage of human hepatocytes and their difficult expansion and cryopreservation. Recent advances in cell biology have led to the concept of "regenerative medicine", based on the therapeutic potential of stem cells (SCs). Different types of SCs are theoretically eligible for liver cell replacement. These include embryonic and fetal SCs, induced pluripotent cells, annex SCs, endogenous liver SCs, and extrahepatic adult SCs. Aim of this paper is to critically analyze the possible sources of SCs suitable for liver repopulation and the results of the clinical trials that have been published until now. PMID: 21048845 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Generating Potential for Regenerative Medicine in Cuba: Porfirio Hernández MD DrSc. National Regenerative Medicine Group, Cuban Ministry of Public Health. MEDICC Rev. 2010 Oct;12(4):10-4 Authors: Vickery K Regenerative medicine has emerged over the last two decades as one of the most rapidly developing fields in medical science, demonstrating unprecedented potential to restore severely damaged or destroyed tissue and even "grow" new tissue in its place. Although the most advanced research, both laboratory and clinical, is taking place in well-financed high-tech settings, including centers in China, India and Brazil; Cuba is one of a handful of other developing countrie -along with Argentina, South Africa, Egypt, Iran, and Malaysia -producing regenerative therapies suited to the needs and capacity of their health care systems.[1] Dr Porfirio Hernández has been at the forefront of the field in Cuba, helping pioneer stem cell research at the Hematology and Immunology Institute in Havana, where he has worked in internal medicine and hematology as clinician and researcher since the 1970s. In this interview with MEDICC Review, he discusses Cuba's regenerative medicine program, particularly development of a simplified method of obtaining adult mononuclear stem cells using existing resources at moderate cost to the national public health system. PMID: 21048538 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Differentiation of Functional Cells from iPS Cells by Efficient Gene Transfer. Yakugaku Zasshi. 2010 Nov;130(11):1527-34 Authors: Kawabata K, Tashiro K, Mizuguchi H Induced pluripotent stem (iPS) cells, which are generated from somatic cells by transducing four genes, are expected to have broad application to regenerative medicine. Although establishment of an efficient gene transfer system for iPS cells is considered to be essential for differentiating them into functional cells, the detailed transduction characteristics of iPS cells have not been examined. By using an adenovirus (Ad) vector containing the cytomegalovirus enhancer/beta-actin (CA) promoters, we have developed an efficient transduction system for mouse mesenchymal stem cells and embryonic stem (ES) cells. Also, we applied our transduction system to mouse iPS cells and investigated whether efficient differentiation could be achieved by Ad vector-mediated transduction of a functional gene. As in the case of ES cells, the Ad vector could efficiently transduce transgenes into mouse iPS cells. We found that the CA promoter had potent transduction ability in iPS cells. Moreover, exogenous expression of a PPARγ gene or a Runx2 gene into mouse iPS cells by an optimized Ad vector enhanced adipocyte or osteoblast differentiation, respectively. These results suggest that Ad vector-mediated transient transduction is sufficient to promote cellular differentiation and that our transduction methods would be useful for therapeutic applications based on iPS cells. PMID: 21048413 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Biology and therapeutic potential of adult retinal stem cells. Can J Ophthalmol. 2010 Aug;45(4):342-51 Authors: Ballios BG, van der Kooy D Retinal degeneration encompasses a constellation of common pathologies for which there is no regenerative treatment. Vision loss has a devastating impact on quality of life and activities of daily living. Pharmacologic treatments serve to stave off disease progression but do not represent a restorative approach. Cellular transplantation is considered to be a promising approach for future therapy for retinal degeneration. There are, however, significant barriers that must be overcome if cell transplantation is to become a clinical reality. In this review, we focus on the need for a cellular replacement therapy for retinal disease and the promise of stem cells as candidate cellular therapeutics. In particular, we discuss the origins of stem cells in the retina, the discovery and characterization of retinal stem cells isolated from adult humans, and their transplantation potential and clinical implications. PMID: 20648091 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | THE FUTURE OF ERECTILE DYSFUNCTION (ED). Arch Esp Urol. 2010 Oct;63(8):740-747 Authors: Porst H About 30-40 % of ED patients are non-responders to PDE 5 inhibitor monotherapy. Lifestyle modifications and physical activity with weight loss enhance PDE 5 inhibitor responsiveness. The same applies for combination therapies such PDE 5 inhibitors + L-Arginine 3.000mg, PDE 5 inhibitors + statins and PDE 5 inhibitors + Yohimbine. Combination of daily dosing with Tadalafil 5 mg and on demand application of sildenafil or vardenafil can improve responsiveness and erection hardness (personal experiences). Guanylate cyclase activators or RhoA-kinase inhibitors, either as monotherapy or in combination with PDE 5 inhibitors have shown in preclinical settings the potential to improve erectile function and represent targets for new ED drugs in the future. Immunophilin ligands were able to ameliorate erectile function after cavernous nerve injury due to pelvic surgery. Although having shown convincing efficacy both in animals and humans the centrally acting Melanocortin Receptor (MCR) Agonists were given up for ED treatment because of unfavorable side-effects.Promising targets for ED therapy in the future is gene therapy with several targets as well as stem cell therapy with adipose-derived or muscle-derived stem cells. PMID: 21048284 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Rat adipose tissue-derived stem cells transplantation attenuates cardiac dysfunction post infarction and biopolymers enhance cell retention. PLoS One. 2010;5(8):e12077 Authors: Danoviz ME, Nakamuta JS, Marques FL, dos Santos L, Alvarenga EC, dos Santos AA, Antonio EL, Schettert IT, Tucci PJ, Krieger JE BACKGROUND: Cardiac cell transplantation is compromised by low cell retention and poor graft viability. Here, the effects of co-injecting adipose tissue-derived stem cells (ASCs) with biopolymers on cell cardiac retention, ventricular morphometry and performance were evaluated in a rat model of myocardial infarction (MI). METHODOLOGY/PRINCIPAL FINDINGS: 99mTc-labeled ASCs (1x10(6) cells) isolated from isogenic Lewis rats were injected 24 hours post-MI using fibrin a, collagen (ASC/C), or culture medium (ASC/M) as vehicle, and cell body distribution was assessed 24 hours later by gamma-emission counting of harvested organs. ASC/F and ASC/C groups retained significantly more cells in the myocardium than ASC/M (13.8+/-2.0 and 26.8+/-2.4% vs. 4.8+/-0.7%, respectively). Then, morphometric and direct cardiac functional parameters were evaluated 4 weeks post-MI cell injection. Left ventricle (LV) perimeter and percentage of interstitial collagen in the spare myocardium were significantly attenuated in all ASC-treated groups compared to the non-treated (NT) and control groups (culture medium, fibrin, or collagen alone). Direct hemodynamic assessment under pharmacological stress showed that stroke volume (SV) and left ventricle end-diastolic pressure were preserved in ASC-treated groups regardless of the vehicle used to deliver ASCs. Stroke work (SW), a global index of cardiac function, improved in ASC/M while it normalized when biopolymers were co-injected with ASCs. A positive correlation was observed between cardiac ASCs retention and preservation of SV and improvement in SW post-MI under hemodynamic stress. CONCLUSIONS: We provided direct evidence that intramyocardial injection of ASCs mitigates the negative cardiac remodeling and preserves ventricular function post-MI in rats and these beneficial effects can be further enhanced by administering co-injection of ASCs with biopolymers. PMID: 20711471 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | THE FUTURE OF ERECTILE DYSFUNCTION (ED). Arch Esp Urol. 2010 Oct;63(8):740-747 Authors: Porst H About 30-40 % of ED patients are non-responders to PDE 5 inhibitor monotherapy. Lifestyle modifications and physical activity with weight loss enhance PDE 5 inhibitor responsiveness. The same applies for combination therapies such PDE 5 inhibitors + L-Arginine 3.000mg, PDE 5 inhibitors + statins and PDE 5 inhibitors + Yohimbine. Combination of daily dosing with Tadalafil 5 mg and on demand application of sildenafil or vardenafil can improve responsiveness and erection hardness (personal experiences). Guanylate cyclase activators or RhoA-kinase inhibitors, either as monotherapy or in combination with PDE 5 inhibitors have shown in preclinical settings the potential to improve erectile function and represent targets for new ED drugs in the future. Immunophilin ligands were able to ameliorate erectile function after cavernous nerve injury due to pelvic surgery. Although having shown convincing efficacy both in animals and humans the centrally acting Melanocortin Receptor (MCR) Agonists were given up for ED treatment because of unfavorable side-effects.Promising targets for ED therapy in the future is gene therapy with several targets as well as stem cell therapy with adipose-derived or muscle-derived stem cells. PMID: 21048284 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Medical applications of organic-inorganic hybrid materials within the field of silica-based bioceramics. Chem Soc Rev. 2010 Nov 4; Authors: Vallet-Regí M, Colilla M, González B Research on bioceramics has evolved from the use of inert materials for mere substitution of living tissues towards the development of third-generation bioceramics aimed at inducing bone tissue regeneration. Within this context hybrid bioceramics have remarkable features resulting from the synergistic combination of both inorganic and organic components that make them suitable for a wide range of medical applications. Certain bioceramics, such as ordered mesoporous silicas, can exhibit different kind of interaction with organic molecules to develop different functions. The weak interaction of these host matrixes with drug molecules confined in the mesoporous channels allows these hybrid systems to be used as controlled delivery devices. Moreover, mesoporous silicas can be used to fabricate three (3D)-dimensional scaffolds for bone tissue engineering. In this last case, different osteoinductive agents (peptides, hormones and growth factors) can be strongly grafted to the bioceramic matrix to act as attracting signals for bone cells to promote bone regeneration process. Finally, recent research examples of organic-inorganic hybrid bioceramics, such as stimuli-responsive drug delivery systems and nanosystems for targeting of cancer cells and gene transfection, are also tackled in this tutorial review (64 references). PMID: 21049136 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Extracellular matrix-derived peptides and myocardial repair. Cell Adh Migr. 2011 Mar 1;5(2):5-7 Authors: Mihardja SS, Yu J, Lee RJ Repairing cardiac tissue remains one of the most challenging goals in tissue engineering. Here, we discuss ways whereby we sought to treat myocardial infarctions using extracellular-matrix derived peptides. Using an ischemia/reperfusion myocardial infarction rodent model, we targeted these extracellular matrix-derived peptides to the myocardial infarct site and were able to induce angiogenesis and alter the negative remodeling seen after an acute myocardial infarction. Our results indicate a potentially new strategy for repairing damaged tissue. PMID: 21048428 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Chitosan nanoparticles: a promising system in novel drug delivery. Chem Pharm Bull (Tokyo). 2010;58(11):1423-30 Authors: Nagpal K, Singh SK, Mishra DN The ability of nanoparticles to manipulate the molecules and their structures has revolutionized the conventional drug delivery system. The chitosan nanoparticles, because of their biodegradability, biocompatibility, better stability, low toxicity, simple and mild preparation methods, offer a valuable tool to novel drug delivery systems in the present scenario. Besides ionotropic gelation method, other methods such as microemulsion method, emulsification solvent diffusion method, polyelectrolyte complex method, emulsification cross-linking method, complex coacervation method and solvent evaporation method are also in use. The chitosan nanoparticles have also been reported to have key applications in parentral drug delivery, per-oral administration of drugs, in non-viral gene delivery, in vaccine delivery, in ocular drug delivery, in electrodeposition, in brain targeting drug delivery, in stability improvement, in mucosal drug delivery in controlled drug delivery of drugs, in tissue engineering and in the effective delivery of insulin. The present review describes origin and properties of chitosan and its nanoparticles along with the different methods of its preparation and the various areas of novel drug delivery where it has got its application. PMID: 21048331 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Preparation and evaluation of biodegradable films containing the potent osteogenic compound BFB0261 for localized delivery. Int J Pharm. 2010 Oct 31; Authors: Umeki N, Sato T, Harada M, Takeda J, Saito S, Iwao Y, Itai S To achieve sustained release of 3-ethyl-4-(4-methylisoxazol-5-yl)-5-(methylthio) thiophene-2-carboxamide (BFB0261), a new potent osteogenic compound for treating bone disorders, we prepared film formulations containing BFB0261 and the following newly synthesized biodegradable polymers by a solvent casting technique: poly(d,l-lactic acid) (PLA), poly(d,l-lactic acid-co-glycolic acid) (PLGA), poly(d,l-lactic acid)-block-poly(ethylene glycol) (PLA-PEG), and poly(d,l-lactic acid-co-trimethylene carbonate) (PLA-TMC) polymers or copolymers. Powder X-ray diffractometry (PXRD), differential thermal analysis (DTA), scanning electron microscopy (SEM), and tensile testing were performed to examine the physicochemical properties of these films. Almost all the films exhibited a smooth and homogeneous surface, as observed by SEM. In addition, PXRD and DTA analysis revealed that BFB0261 existed in an amorphous state in the films. The in vitro release of BFB0261 from PLA100 (M(w): 251kDa), PLAPEG9604H (PLA/PEG ratio: 96:4; M(w): 181kDa), PLAPEG8515H (PLA/PEG ratio: 85:15; M(w): 51.5kDa), or PLAPEG8020 (PLA/PEG ratio: 80:20; M(w): 33.7kDa) films followed zero-order kinetics with slow release up to 12 weeks following incubation. Although release of BFB0261 from PLA-TMC films followed first-order kinetics, sustained release of BFB0261 for 12 weeks was still observed for PLATMC8416 (PLA/TMC ratio: 84:16; M(w): 170kDa) films. Furthermore, when the BFB0261-loaded films constructed from various polymers were implanted subcutaneously on rat backs, the PLAPEG8515H and PLATMC8416 films were capable of achieving sustained release of BFB0261 at the administrated site for 12 weeks. Therefore, the present data indicate that films constructed from PLAPEG8515H or PLATMC8416 may be applicable to bone or tissue engineering. PMID: 21047548 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Self-Crimping, Biodegradable, Electrospun Polymer Microfibers. Biomacromolecules. 2010 Nov 3; Authors: Surrao DC, Hayami JW, Waldman SD, Amsden BG Semicrystalline poly(l-lactide-co-ε-caprolactone) (P(LLA-CL)) was used to produce electrospun fibers with diameters on the subcellular scale. P(LLA-CL) was chosen because it is biocompatible and its chemical and physical properties are easily tunable. The use of a rotating wire mandrel as a collection device in the electrospinning process, along with high collection speeds, was used to align electrospun fibers. Upon removal of the fibers from the mandrel, the fibers shrunk in length, producing a crimp pattern characteristic of collagen fibrils in soft connective tissues. The crimping effect was determined to be a result of the residual stresses resident in the fibers due to the fiber alignment process and the difference between the operating temperature (T(op)) and the glass-transition temperature (T(g)) of the polymer. The electrospun fibers could be induced to crimp by adjusting the operating temperature to be greater than that of the polymer glass-transition temperature. Moreover, the crimped fibers exhibited a toe region in their stress-strain profile that is characteristic of collagen present in tendons and ligaments. The crimp pattern was retained during in vitro degradation over 4 weeks. Primary bovine fibroblasts seeded onto these crimped fibers attached, proliferated, and deposited extracellular matrix (ECM) molecules on the surface of the fiber mats. These self-crimping fibers hold great promise for use in tissue engineering scaffolds for connective tissues that require fibers similar in structure to that of crimped collagen fibrils. PMID: 21047054 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [Research progress of cells and cell-transplantation methods for periodontal tissue engineering]. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Oct;24(10):1249-52 Authors: Li W, Meng X OBJECTIVE: To introduce the cells and cell-transplantation methods for periodontal tissue engineering. METHODS: Recent literature about application of cell-based therapy in periodontal tissue engineering was extensively reviewed, the cells and cell-transplantation methods were investigated. RESULTS: Mesenchymal stem cells were important cell resources for periodontal tissue engineering, among which peridontal ligament stem cells were preferred. Bone marrow mesenchymal stem cells had several disadvantages in clinical application, and adipose-derived stem cells might be a promising alternative; different transplantation methods could all promote periodontal regeneration to some extent. Single-cell suspension injection could only promote a little gingival regeneration, and tissue engineered scaffolds still needed some improvement to be used in periodontal regeneration, while cell sheet technique, with great cell loading ability and no need of scaffolds, could promote regeneration of cementum, periodontal ligament, and alveolar bone under different conditions. CONCLUSION: Multipotent stem cells are fit to be used in periodontal tissue engineering; improvement of cell-transplantation methods will further promote periodontal regeneration. PMID: 21046816 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [Effect of collagen type II on redifferentiation of dedifferentiated rabbit chondrocytes]. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Oct;24(10):1244-8 Authors: Sun M, Zhu L, Lv D OBJECTIVE: Collagen type II is a characteristic molecular of chondrocyte. With continuous subculture of chondrocytes, they progressively lose the ability to express collagen type II. To observe the effect of collagen type II on redifferentiation of dedifferentiated rabbit chondrocytes so as to lay a experimental foundation for use of chondrocytes in cartilage tissue engineering. METHODS: Cartilage was harvested under sterile conditions from tibio-femoral joints of 7-month-old New Zealand white rabbit. The rabbit articular chondrocytes were subcultured in vitro to the 7th generation (named P1-P7). Dedifferentiated rabbit chondrocytes were chosen by RT-PCR, real-time PCR, and 1, 9-dimethylmethylene blue (DMMB) assay. Then dedifferentiated rabbit chondrocytes were treated with various concentrations (0, 0.5%, 1.0%, and 1.5%) of exogenous collagen type II. The redifferentiation of dedifferentiated chondrocytes was measured by RT-PCR and real-time PCR, and the glycosaminoglycan content was determined by DMMB assay. RESULTS: The glycosaminoglycan content of P1-P7 chondrocytes were (12.20 +/- 0.17), (11.20 +/- 0.24), (11.18 +/- 0.16), (10.89 +/- 0.50), (8.73 +/- 0.19), (9.39 +/- 0.32), and (8.18 +/- 0.20) microg, respectively, showing no significant difference (P > 0.05) among P2, P3, and P4, and showing significant differences (P < 0.05) among other generations. The mRNA of collagen type I, collagen type II, and aggrecan expressed at P4-P7, showing no significant difference in the mRNA expression of collagen type I (P > 0.05) and significant differences in the mRNA expressions of collagen type II and aggrecan (P < 0.05) among P4-P7. The glycosaminoglycan content at concentrations of 0, 0.5%, 1.0%, and 1.5% were (8.20 +/- 0.16), (14.61 +/- 0.33), (13.93 +/- 0.25), and (19.59 +/- 0.46) microg, showing significant differences among different concentrations (P < 0.05). With exogenous collagen type II concentrations increased, the mRNA expressions of collagen type II and aggrecan gene were up-regulated gradually, but collagen type I gene was down-regulated, showing significant differences (P < 0.05). CONCLUSION: Collagen type II can promote redifferentiation and activation of dedifferentiated rabbit chondrocytes. PMID: 21046815 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [Comparison of myogenic differentiation ability of adipose-derived stem cells from different sites in rabbit]. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Oct;24(10):1228-32 Authors: Yuan Q, Zeng X, Chen L, Peng E, Ye Z OBJECTIVE: To compare the myogenic differentiation ability in vitro of rabbit adipose-derived stem cells (ADCSs) from different sites so as to provide ideal seed cells for repair and reconstruction of urinary tract. METHODS: Adipose tissues were obtained from the nape of the neck, post peritoneum, and vicinity of epididymis of a 4-month-old male New Zealand rabbit and ADSCs were harvested through collagenase digestion. ADSCs were purified by differential attachment method. The protein marker CD44 of rabbit ADSCs was used to identify the stem cells by immunocytochemistry, then the 5th generation of ADSCs were induced to differentiate into adipogenic, osteogenic, and myogenic cells. Multi-differentiation was confirmed by Oil red O staining, von Kossa staining, and RT-PCR. Myogenic differentiation abilities of ADSCs from 3 different sites were compared between the control group (L-DMEM medium containing 10%FBS) and the experimental group (myogenic medium) by RT-PCR method. RESULTS: ADSCs could be easily isolated from adipose tissues of the nape of the neck, post peritoneum, and vicinity of epididymis. ADSCs displayed a typical cobblestone morphology. Brown particles could be seen in ADSCs by CD44 immunocytochemistry staining. Oil red O staining showed red fat drops in ADSCs after 14 days of adipogenic culture. Black matrix could be seen in ADSCs by von Kossa staining after 28 days of osteogenic culture. RT-PCR detection showed moderate alpha-actin expression in the control group and strong alpha-actin expression in the experimental group after 42 days of myogenic culture. The growth rate of alpha-actin from the adipose tissue of post peritoneum (28.622% +/- 4.879%) was significantly lower (P < 0.05) than those from the adipose tissues of the nape of the neck (35.471% +/- 3.434%) and vicinity of epididymis (38.446% +/- 4.852%). CONCLUSION: The ADSCs from different sites show different myogenic differentiation abilities in vitro. ADSCs from the adipose tissues of the nape of the neck and vicinity of epididymis can be used as ideal seed cells for tissue engineering of lower urinary tract. PMID: 21046812 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | [Effect of cryopreservation on growth and osteogenesis of human adipose-derived stem cells]. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010 Oct;24(10):1224-7 Authors: Liu G, Li Y, Sun J, Zhou H, Cui L OBJECTIVE: As one of the adult stem cells, adipose-derived stem cells (ADSCs) have become an important seed cell source for tissue engineering recently. But whether the thawed cryopreserved ADSCs could be used to tissue engineered bone remains unknown. To investigate the effect of cryopreservation on the growth and osteogenesis of ADSCs in vitro. METHODS: The ADSCs were isolated from the adipose aspirates by collagenase digestion method. For the experimental group, the 2nd generation cells were stored with a simple method of cryopreservation by slow cooling with dimethyl sulphoxide as a cryoprotectant and rapid thawing. After cryopreserved in liquid nitrogen for 4 weeks, ADSCs were recovered and cultured in osteogenic media, with non-cryopreserved ADSCs as the control group. The osteogenic differentiation was evaluated by alkaline phosphatase (ALP) staining and Alizarin red O staining at 2 and 3 weeks respectively. The cell growth and osteogenesis of ADSCs were further determined using DNA assay and the ALP activity and calcium content were measured. RESULTS: The survival percentage of the cryopreserved cells was 90.44% +/- 2.62%. The cell numbers and ALP activity increased with osteogenic induction time, and reach plateaus at 7 days and 11 days, respectively. The ALP staining and Alizarin red O staining results were both positive at 2 weeks and 3 weeks after osteogenic induction, respectively. And no significant difference in the cells number, ALP activity, and calcium content were found between experimental group and control group (P > 0.05). CONCLUSION: Cryopreservation does not affect the growth and osteogenesis of ADSCs, and the cryopreserved ADSCs can be used as cell source for tissue engineered bone. PMID: 21046811 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Polarization and migration of hematopoietic stem and progenitor cells rely on the RhoA/ROCK I pathway and an active reorganization of the microtubule network. J Biol Chem. 2010 Oct 8;285(41):31661-71 Authors: Fonseca AV, Freund D, Bornhäuser M, Corbeil D Understanding the physiological migration of hematopoietic progenitors is important, not only for basic stem cell research, but also in view of their therapeutic relevance. Here, we investigated the role of the Rho kinase pathway in the morphology and migration of hematopoietic progenitors using an ex vivo co-culture consisting of human primary CD34(+) progenitors and mesenchymal stromal cells. The addition of the Rho kinase inhibitor Y-27632 led to the abolishment of the uropod and microvillar-like structures of hematopoietic progenitors, concomitant with a redistribution of proteins found therein (prominin-1 and ezrin). Y-27632-treated cells displayed a deficiency in migration. Time-lapse video microscopy revealed impairment of the rear pole retraction. Interestingly, the knockdown of ROCK I, but not ROCK II, using RNA interference (RNAi) was sufficient to cause the referred morphological and migrational changes. Unexpectedly, the addition of nocodazole to either Y-27632- or ROCK I RNAi-treated cells could restore their polarized morphology and migration suggesting an active role for the microtubule network in tail retraction. Finally, we could demonstrate using RNAi that RhoA, the upstream regulator of ROCK, is involved in these processes. Collectively, our data provide new insights regarding the role of RhoA/ROCK I and the microtubules in the migration of stem cells. PMID: 20682776 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Changes in the endogenous BMP expression during redifferentiation of chondrocytes in 3D cultures. Int J Mol Med. 2010 Sep;26(3):317-23 Authors: Albrecht C, Schlegel W, Bartko P, Eckl P, Jagersberger T, Vécsei V, Marlovits S Engineering cartilage tissue is challenging, mainly because chondrocytes lose their differentiated phenotype when cultured in monolayer. The aim of this study was to analyse the influence of 3D-culture conditions on the redifferentiation of chondrocytes, devoting special attention to BMPs. Dedifferentiated chondrocytes were seeded onto two different scaffolds (Bio-Gide and HYAFF-11) and were then cultured for 38 days. Every week, samples were taken for gene expression analysis and immunohistochemistry. In both scaffolds an increasing differentiation was observed caused by an increase in Col2 and a reduction in Col1 expression. The various BMPs were regulated, albeit differently by the changing culture conditions. While GDF-5 and BMP-4 expression increased in the monolayer culture in comparison with native cartilage and decreased again in the 3D culture, the BMP-2 and BMP-6 expression decreased dramatically in the monolayer as well as in the 3D culture. BMP-7 was not detectable in any probe. Scaffold cultivation appears to stimulate the induction of redifferentiation, but is not sufficient to induce expression of BMP-2 -6 or -7. Since, in comparison to cartilage development, there is a lack of surrounding signal centres, external stimuli seem to be required to obtain complete redifferentiation. Our data indicate that a combination of BMP-2, -6 and -7 may be promising for this purpose. PMID: 20664946 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Bladder reconstruction with adipose-derived stem cell-seeded bladder acellular matrix grafts improve morphology composition. World J Urol. 2010 Aug;28(4):493-8 Authors: Zhu WD, Xu YM, Feng C, Fu Q, Song LJ, Cui L PURPOSE: To assess the feasibility of seeding adipose-derived stem cells (ADSCs) onto bladder acellular matrix grafts (BAMGs) for bladder reconstruction in a rabbit model. METHODS: Autologous ADSCs were isolated, expanded and identified by flow cytometry. In the experimental group, ADSCs were seeded onto BAMGS for reconstructing bladder defects in 12 male rabbits. Unseeded BAMGs were used for bladder reconstruction in the control group of 12 rabbits. Cystography was performed at 4, 12 and 24 weeks after grafts implantation. Following cystography, the animals were killed and grafts were harvested; H&E and immunohistochemical staining were performed with cytokeratin AE1/AE3, smooth muscle alpha-actin and S-100 markers. RESULTS: Flow cytometry demonstrated that the ADSCs expressed CD90, CD44, CD105, CD166 and CD34, but not CD45 or CD106. The cells demonstrated good biocompatibility with BAMGs. At 24 weeks, in the experimental group, the reconstructed bladders reached a mean volume of 94.68 +/- 3.31% of the pre-cystectomy bladder capacity. Complete regeneration of smooth muscle and nerve tissue was evident. Regenerated SMCs, urothelium and nerve cells stained positively for alpha-smooth muscle actin, AE1/AE3 and S-100. In the control group, the mean bladder volume was 69.33 +/- 5.05% of the pre-cystectomy volume; histologically, the control group was characterized by multi-layered urothelium without evidence for organized muscle or nerve tissue. CONCLUSIONS: These data demonstrate that seeding ADSCs onto BAMGs promote regeneration of smooth muscle and nervous tissue regeneration in a rabbit model. This compound graft was more suitable for bladder reconstruction than BAMG alone. PMID: 20091038 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | [Xenogenic corneal acellular matrix as carrier for reconstruction of biological cornea epithelium-scaffold-endothelium compound]. Zhonghua Yan Ke Za Zhi. 2007 May;43(5):437-41 Authors: Fan XQ, Chen P, Fu Y OBJECTIVE: To investigate the method and feasibility of constructing biological cornea by culturing corneal epithelial and endothelial cells on the scaffold of xenogenic corneal acellular matrix (XCAM) in vitro. METHODS: Porcine cornea was prepared as XCAM by application of detergent 1% Triton X-100 and freeze-drying process. After the carrier has rehydrated, rabbit epithelial and endothelial cells were seeded on each side of XCAM. After 2 weeks of culture, the reconstructed tissue of epithelium-scaffold-endothelium compound was examined by histological studies by HE staining and scanning electron microscope (SEM). The epithelium was examined by immunohistochemical studies using antibodies to cytokeratin (CK3), and the endothelium was stained with trypan blue and alizarin red. RESULTS: Reconstructed biological cornea was composed of epithelium, acellular stroma and endothelium. Four to five layers of stratified flat cells were formed on the surface of XCAM, which were stained positively by CK3. Continuous monolayer cells located on the endothelial side, which were alive and showed honeycomb-like shape via dual staining with trypan blue and alizarin red, cells arranged tightly. Under SEM, epithelial cells showed several layers with the morphology of flat and spindle cells alternatively, endothelial cells showed polygonal shape with microvillus over the surface. CONCLUSIONS: The biological corneal tissue reconstructed in vitro possessed three layers: the epithelium, scaffold and the endothelium. XCAM provides ideal surface for corneal epithelial and endothelial cells' adhesion and proliferation, it is desired to be used as scaffold for reconstruction of cornea in vitro. PMID: 17706094 [PubMed - indexed for MEDLINE] | | | | | | | | | |  | |  | |  |
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