Global Medical Discovery features paper: Different Effects of p52SHC1 and p52SHC3 on the Cell Cycle of Neurons and Neural Stem Cells

Significance Statement

Many studies clearly demonstrate the important roles of SHC1 and SHC3 in neuronal functions. However, the exact functional differences between SHC1 and SHC3, especially on the aspect of their isoforms, have not been revealed in primary neurons or neuronal precursor cells. In this study, we used

RNA interference to knock down the expression of p52SHC1and p52SHC3 in purified primary cortical neurons and neural stem cells, respectively. We also used adenovirus to overexpress p52SHC1 in primary neurons and p52SHC3 in neural stem cells to confirm their roles in neural cell cycle.

In the present study, p52SHC1 RNAi  resulted in significantly fewer percentage of G2-M phase cells in primary neural stem cells along with down-regulated cyclin A and cyclin E proteins. However, the exogenous expression of SHC1 in purified primary cortical neurons in this study did not seem to change the cell cycle distribution, although cyclin A, CDK2 and p-CDK2 were all up-regulated.

In Ning Tang and colleagues study, knockdown of p52SHC3 expression by RNAi significantly affected the cell cycle distribution and the expression levels of many cell cycle regulators. Specifically, RNAi of p52SHC3 decreased the percentage of G0/G1 phase neurons but increased the percentages of S phase and G2/M phase neurons, The changed cell cycle distribution may be caused by the changed levels of the following proteins: the upregulation of cyclin D1 which may cause reduction in the percentage of G0/G1 phase neurons; the up-regulation of cyclin E and CDK2 which may push cells to pass the G1/S boundary to enter S phase; and the up-regulation of cyclin A and CDK2 which may lead to the cells to enter G2/M phase. All these results clearly indicated that some of the neurons had reentered the cell cycle after p52SHC3 RNAi. Overexpression of exogenous p52SHC3 in neural stem cells increased the percentage of G0-G1 phase cells and decreased the percentage of G2-M phase cells by downregulating the protein levels of cyclin A, cyclin D1, and cyclin E, demonstrating a CDK2-independent cell cycle arrest.

Ning Tang and colleagues deminstrated that p52SHC1 plays an essential role in regulating cellular proliferation and p52SHC3 has crucial function in maintaining the mitotic quiescence of neurons. Controlling these domain-mediated signals could be a target in determining the fate of neural cells in the cell cycle.   

 

About The Author

Dr. Ning Tang received his Bachelor Degree in biology science from Shandong University, China, in 2003. He received his Ph. D from Institute of Basic Medical Sciences, Academy of Military Medical Sciences in 2010, majored in cell biology.

Currently, he works in Reproductive Medicine Center of Jinan Military General Hospital as an embryologist, Jinan, China. 

About The Author

Dr. Dan Lyu received her Bachelor Degree in 2005, from Chengdu Sport University, Chengdu, China. In 2008, she received her Master Degree from Hebei Medical University, Shijiazhuang, China and in 2011, she received her Ph,D from Capital Medical University, Beijing, China, majored in pain medicine.

She is now a clinical doctor in Tianjin First Central Hospital, Tianjin, China. Her research focuses on pain related neural pathological and physiological alteration. 

 

Reference

Tang N^1,2, Lyu D^1,3, Liu T¹, Chen F¹, Jing S¹, Hao T², Liu S¹. Different Effects of p52SHC1 and p52SHC3 on the Cell Cycle of Neurons and Neural Stem Cells. J Cell Physiol. 2016 ;231(1):172-80. doi: 10.1002/jcp.25069.

Show Affiliations

1 State Key Laboratory of Proteomics and, Department of Neurobiology, Institute of Basic Medical Sciences, Beijing, P. R. China.

2 Reproductive Medicine Center, Jinan Military General Hospital, Jinan, P. R. China.

3 Dan Lyu is currently working in Department of Pain Management, Tianjin First Center Hospital, Tianjin, P. R. China.  

 

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Abrogation of Age-Induced MicroRNA-195 Rejuvenates the Senescent Mesenchymal Stem Cells by Reactivating Telomerase

Journal Reference

Stem Cells. 2016 Jan;34(1):148-59.

Okada M, Kim HW, Matsu-Ura K, Wang YG, Xu M, Ashraf M.

Department of Pathology and Lab of Medicine, University of Cincinnati Medical Center, Cincinnati, Ohio, 45267, USA.

Abstract

Previously, we reported that a novel subpopulation of young mesenchymal stem cells (YMSCs) existed in old bone marrow, which possessed high antiaging properties as well as excellent efficacy for cardiac repair. MicroRNAs (miRNAs) have emerged as key regulators in post-transcriptional gene expression programs, and however, it is unknown whether miRNAs directly control stem cell senescence. Here we present the first evidence that miR-195 overexpressed in old MSCs (OMSCs) induces stem cell senescence deteriorating their regenerative ability by directly deactivating telomerase reverse transcriptase (Tert), and abrogation of miR-195 can reverse stem cell aging. MiRNAs profiling analysis in YMSCs and OMSCs by microarray showed that miR-140, miR-146a/b, and miR-195 were significantly upregulated in OMSCs, which led us to hypothesize that these are age-induced miRNAs involved in stem cell senescence. Of these miRNAs, we found miR-195 directly targeted 3′-untranslated region of Tert gene by computational target prediction analysis and luciferase assay, and knockdown of miR-195 significantly increased Tert expression in OMSCs. Strikingly, miR-195 inhibition significantly induced telomere relengthening in OMSCs along with reduced expression of senescence-associated β-galactosidase. Moreover, silencing miR-195 in OMSCs by transfection of miR-195 inhibitor significantly restored antiaging factors expression including Tert and Sirt1 as well as phosphorylation of Akt and FOXO1. Notably, abrogation of miR-195 markedly restored proliferative abilities in OMSCs. Transplantation of OMSCs with knocked out miR-195 reduced infarction size and improved LV function. In conclusion, rejuvenation of aged stem cells by miR-195 inhibition would be a promising autologous therapeutic strategy for cardiac repair in the elderly patients.

© 2015 AlphaMed Press.

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Vitronectin promotes the progress of the initial differentiation stage in cerebellar granule cells

Journal Reference

Mol Cell Neurosci. 2016 Jan;70:76-85.

Hashimoto K¹, Sakane F¹, Ikeda N¹, Akiyama A¹, Sugahara M¹, Miyamoto Y².

Show Affiliations

1. Graduate School of Humanities and Sciences, Ochanomizu University, Otsuka 2-1-1, Bunkyo-ku, Tokyo 112-8610, Japan.
2. Graduate School of Humanities and Sciences, Ochanomizu University, Otsuka 2-1-1, Bunkyo-ku, Tokyo 112-8610, Japan. Electronic address: miyamoto.yasunori@ocha.ac.jp.

Abstract

Vitronectin (VN), which is an extracellular matrix protein, is known to be involved in the proliferation and differentiation of primary cultured cerebellar granule cell precursors (CGCPs); however, the effect of Vitronectin is not fully understood. In this study, we analyzed the effects of Vitronectin loss on the proliferation and differentiation of CGCPs in Vitronectin knockout (VNKO) mice in vivo. First, immunohistochemistry showed that Vitronectin was distributed in the region from the inner external granule layer (iEGL) through the internal granule layer (IGL) in wild-type (WT) mice. Next, we observed the formation of the cerebellar cortex using sagittal sections of VNKO mice at postnatal days (P) 5, 8 and 11. Loss of Vitronectin suppressed the ratio of NeuN, a neuronal differentiation marker, to positive   cerebellar granule cells (CGCs) in the external granule layer (EGL) and the ratio of CGCs in the IGL at P8, indicating that the loss of Vitronectin suppresses the differentiation into CGCs. However, the loss of Vitronectin did not significantly affect the proliferation of CGCPs. Next, the effect of Vitronectin loss on the initial differentiation stage of CGCPs was examined. The loss of Vitronectin increased the expression levels of Transient axonal glycoprotein 1 (TAG1), a marker of neurons in the initial differentiation stage, in the cerebella of VNKO mice at P5 and 8 and increased the ratio of TAG1-positive cells in the primary culture of VNKO-derived CGCPs, indicating that the loss of VN accumulates the CGCPs in the initial differentiation stage. Taken together, these results demonstrate that Vitronectin promotes the progress of the initial differentiation stage of CGCPs.

Copyright © 2015 Elsevier Inc. All rights reserved.

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Modulation of the gene expression of annulus fibrosus-derived stem cells using poly(ether carbonateurethane)urea scaffolds of tunable elasticity

Significance Statement

Annulus fibrosus (AF) injuries lead to substantial intervertebral disc deterioration which characterizes degenerative disc diseases. Repair of AF, however, remains challenging due to the tremendous heterogeneity of Annulus fibrosus tissue. Since the differentiation of stem cells significantly relies on the elasticity of substrate, a series of biodegradable poly(ether carbonate urethane)urea (PECUU) materials whose elasticity resembled that of native Annulus fibrosus tissue were synthesized in this study. When Annulus fibrosus-derived stem cells (AFSCs) were cultured on electrospun PECUU fibrous scaffolds, the gene expression and protein production of major matrix components, including collagen-I, collagen-II and aggrecan, and cell traction forces gradually changed with the elasticity of PECUU. Such substrate elasticity-dependent modulation of Annulus fibrosus-derived stem cells was similar to the gradual transition in the genetic, biochemical, and biomechanical characteristics of cells from inner to outer regions of native Annulus fibrosus tissue. This work has, for the first time, revealed that Annulus fibrosus-derived stem cells are able to present different gene expression patterns simply as a result of the elasticity of scaffold material. Findings from this study will help develop adequate materials for Annulus fibrosus regeneration.

About The Author

Professor Bin Li is the director of the Biomaterials and Cell Mechanics Laboratory (BCML) of Orthopedic Institute at Soochow University, Suzhou, China. He received the bachelor degree in 1996 and PhD degree in Materials Science from Tsinghua University in 2001. He then joined the Institute of Materials Research and Engineering, Singapore as a Research Associate until 2004. After that he consecutively pursued research training at Carnegie Mellon University, University of Pittsburgh, and Harvard University until 2009, when he took the current position as a full professor at Soochow University. He is the recipient of the Orthopaedics Research Award (1st prize) from Chinese Orthopaedic Association, Xu Guangqi Program from the French Embassy in China, and France Talent Innovation from the Consulate General of France in Shanghai. He currently serves as the chair of China Development Committee of International Chinese Musculoskeletal Research Society (ICMRS). He is a fellow of Chinese Orthopaedic Research Society (CORS), Chinese Association of Orthopaedic Surgeons (CAOS), Chinese Association of Rehabilitation Medicine (CARM), and International Society of Orthopaedic Surgery and Traumatology (SICOT). He has delivered about 40 invited and is the author of over 70 publications and 9 book chapters. He now leads a multidisciplinary research group studying biomaterials for bone and cartilage repair, stem cells and tissue engineering, smart molecular recognition and controlled release, surface modification and functionalization, and cellular biomechanics and mechanobiology.

About The Author

Dr. Caihong Zhu is a research associate and a member of the Biomaterials and Cell Mechanics Laboratory (BCML) of Orthopedic Institute at Soochow University. She received the bachelor degree in Polymer Chemistry from Nanjing University in 2001 and PhD degree in Polymer Chemistry from Soochow University in 2010. She joined Soochow University in 2012. Her research interests include biomaterials for bone and intervertebral disc regeneration and controlled drug delivery.

  

About The Author

Dr. Jun Li is an orthopaedic surgeon who received his PhD degree at the Soochow University. Currently, he is a postdoctoral researcher at Shenzhen University. His major research interests include bone and cartilage regeneration via stem cell transplantation and osteoporosis.

Journal Reference

Acta Biomater. 2016;29:228-38.

Caihong Zhu, Jun Li, Chen Liu, Pinghui Zhou, Huilin Yang, Bin Li.

Department of Orthopaedics, The First Affiliated Hospital, Orthopaedic Institute, Soochow University, 188 Shizi St, Suzhou, Jiangsu 215006, China.

These authors contributed equally to this study. Email: binli@suda.edu.cn

Abstract

Annulus fibrosus (AF) injuries commonly lead to substantial deterioration of the intervertebral disc (IVD). While tissue engineering has recently evolved into a promising approach for AF regeneration, it remains challenging due to the cellular, biochemical, and mechanical heterogeneity of AF tissue. In this study, we explored the use of AF-derived stem cells (AFSCs) to achieve diversified differentiation of cells for AF tissue engineering. Since the differentiation of stem cells relies significantly on the elasticity of the substrate, we synthesized a series of biodegradable poly(ether carbonate urethane)urea (PECUU) materials whose elasticity approximated that of native AF tissue. When AFSCs were cultured on electrospun PECUU fibrous scaffolds, the gene expression of collagen-I in the cells increased with the elasticity of scaffold material, whereas the expression of collagen-II and aggrecan genes showed an opposite trend. At the protein level, the content of collagen-I gradually increased with substrate elasticity, while collagen-II and GAG contents decreased. In addition, the cell traction forces (CTFs) of AFSCs gradually decreased with scaffold elasticity. Such substrate elasticity-dependent changes of AFSCs were similar to the gradual transition in the genetic, biochemical, and biomechanical characteristics of cells from inner to outer regions of native AF tissue. Together, findings from this study indicate that AFSCs, depending on the substrate elasticity, have strong tendencies to differentiate into various types of AF-like cells, thereby providing a solid foundation for the tissue engineering applications of AFSCs.

Copyright © 2016. Published by Elsevier B.V.

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The development of statin-based therapy for patients with hepatitis C virus (HCV) infection using human induced pluripotent stem (iPS) cell technology

Significance Statement

Human induced pluripotent stem cells (hiPSCs) have been expected to transform drug discovery by providing physiologically relevant cells for toxic compound identification and compound screening. When Shimada M et al. (J Hepatol. 2012;56: 299-300) considered two reports (Moriguchi H et al.; Hepatology. 2010; 51: 344–345 and 351–352) published in 2010 investigating the antiviral efficacy of pitavastatin against hepatitis C virus (HCV) infection in vitro, they conducted a randomized controlled trial (J Hepatol. 2012;56: 299-300). As a result, the results of 2010 proof-of-concept studies of the antiviral efficacies and safety of pitavastatin against HCV infection using a replicon system and human hepatocyte-like cells from hiPSCs (Moriguchi H et al.; Hepatology. 2010; 51: 344–345 and 351–352) were confirmed in a randomized controlled trial published by Shimada M et al. in 2012 (J Hepatol. 2012;56: 299-300). Therefore, this series of studies (Moriguchi H et al.; Hepatology. 2010; 51: 344–345 and 351–352, Shimada M et al.; J Hepatol. 2012; 56: 299-300) would be the first to report clinical applications of hiPSCs. Furthermore, after the clinical trial by Shimada M et al. (J Hepatol. 2012; 56: 299-300), the antiviral efficacies and safeties of pitavastatin against HCV infection were more confirmed in the two clinical studies (Kohjima M et al.; J Med Virol. 2013: 85: 250-260 and Yokoyama S et al.; Aliment Pharmacol Ther. 2014; 39: 443-444). Therefore, to investigate the antiviral efficacies and safety of pitavastatin against HCV infection using a replicon system and human hepatocyte-like cells from hiPSCs (Moriguchi H et al.; Hepatology. 2010; 51: 344–345 and 351–352) would be a rational approach as new drug discovery. 

About The Author

Dr. Moriguchi H obtained his Ph.D. from the University of Tokyo in 2007. He was a visiting associate professor (full time) from 2000 to 2006 and a project professor from 2006 to 2009 at the University of Tokyo. He is currently at Oak Clinic company. His research focuses on clinical epidemiology (1996, Gut, etc), clinical decision analysis (2012, Hepatology, etc), stem cell research (2011, Cell Mol Life Sci, etc) and reproductive medicine (2012, Hum Reprod, etc) in Gastroenterology, Hepatology, cancers, stem cell research and reproductive medicine.

Journal Reference

Clin Res Hepatol Gastroenterol. 2015;39(5):541-3.

Moriguchi H.

Oak Clinic, 2-7-9, Tamade-Nishi, Nishinari-ku, 557-0045 Osaka, Japan. Electronic address: moriguchi_h@oakclinic-group.com.

Abstract

Human induced pluripotent stem (iPS) cells may transform drug discovery. Here I show an example of the development of statin (HMG-CoA reductase inhibitors)-based therapy for patients with hepatitis C virus (HCV) infection using human iPS cell technology. When Shimada et al. considered the two reports on the antiviral effects of pitavastatin for HCV infection in vitro by Moriguchi et al., they conducted a randomized controlled trial. As a result, a proof-of-concept for the antiviral effect of pitavastatin against HCV infection using human iPS cell technology by Moriguchi et al. was confirmed in the randomized controlled trial by Shimada et al. in 2012. Therefore, above-mentioned a series of studies became to the first to report the clinical application of human iPS cells. Furthermore, here I propose that new clinical research methods using human iPS cell technology will be able to circumvent the limitations of conventional randomized controlled trials (RCTs) for the purpose of personalized medicine in the clinical setting.

Copyright © 2015 Elsevier Masson SAS. All rights reserved.

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Apoptotic neurons induce proliferative responses of progenitor cells in the postnatal neocortex

Journal Reference

Exp Neurol. 2015 Nov;273:126-37.

Petrenko V¹, Mihhailova J¹, Salmon P¹, Kiss JZ².

Show Affiliations

1. Department of Neurosciences, University of Geneva Medical School, CH-1211 Geneva 4, Switzerland.
2. Department of Neurosciences, University of Geneva Medical School, CH-1211 Geneva 4, Switzerland. Electronic address: Jozsef.Kiss@unige.ch.

Abstract

Apoptotic cell death is the leading cause of neuronal loss after neonatal brain injury. Little is known about the intrinsic capacity of the immature cerebral cortex for replacing dead cells. Here we test the hypothesis that neuronal apoptosis is able to trigger compensatory proliferation in surrounding cells. In order to establish a “pure” apoptotic cell death model and to avoid the confounding effects of broken blood-brain barrier and inflammatory reactions, we used a diphtheria toxin (DT) and diphtheria toxin receptor (DTR) system to induce ablation of layer IV neurons in the rodent somatosensory cortex during the early postnatal period. We found that DT-triggered apoptosis is a slowly progressing event lasting about for 7days. While dying cells expressed the morphological features of apoptosis, we could not detect immunoreactivity for activated caspase-3 in these cells. Microglia activation and proliferation represented the earliest cellular responses to apoptotic cell death. In addition, we found that induced apoptosis triggered a massive proliferation of undifferentiated progenitor cell pool including Sox2 as well as NG2 cells. The default differentiation pattern of proliferating progenitors appears to be the glial phenotype; we could not find evidence for newly generated neurons in response to apoptotic neuronal death. These results suggest that mitotically active progenitor populations are intrinsically capable to contribute to the repair process of injured cortical tissue and may represent a potential target for neuronal replacement strategies.

Copyright © 2015. Published by Elsevier Inc.

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Electrospun Polycaprolactone 3D Nanofibrous Scaffold with Interconnected and Hierarchically Structured Pores for Bone Tissue Engineering.

Significance Statement

Ultrathin fibers (with diameters from tens to hundreds of nanometers, commonly known as electrospun nanofibers) prepared via the electrospinning method are of great interests for tissue engineering applications, because electrospun nanofibers have diameters similar to those of fibrous structures in natural extracellular matrix (ECM).  The major limitation of electrospun scaffolds is owing to their morphological structure of overlaid nanofiber mats with apparent/equivalent pore sizes in sub-micrometers; in other words, electrospun nanofibrous mats lack the needed macropores (with sizes from tens to hundreds of micrometers) for cell growth and tissue formation.

In the reported studies, novel electrospun three-dimensional (3D) nanofibrous scaffold has been developed by an innovative and convenient approach (i.e., thermally induced nanofiber self-agglomeration followed by freeze drying) from a biopolymer of polycaprolactone (PCL) for the first time, and the scaffold possesses interconnected and hierarchically structured pores (in specific, the macropores with sizes in hundreds of micrometers would maintain the structural stability of scaffold, support cell proliferation, ECM deposition, and tissue formation; the medium pores with sizes in tens of micrometers or smaller would facilitate the diffusion of nutrients and promote the formation of vascularization, while the small pores with sizes in micrometers or smaller would have impacts on some cell behaviors such as seeding and genes expressions).  The novel polycaprolactone 3D scaffold is soft and elastic with very high porosity of ~96.4%, thus it is morphologically/structurally similar to natural ECM and well-suited for cell functions (e.g., adhesion, proliferation, migration, and differentiation) and tissue formation.

The in vitro studies reveal that the novel scaffold can lead to high cell viability; more importantly, it is able to promote more potent bone morphogenetic protein 2 (BMP2) induced chondrogenic (rather than osteogenic) differentiation of mouse bone marrow mesenchymal stem cells (mBMSCs).  Consistent to the in vitro findings, the in vivo results indicate that electrospun polycaprolactone 3D scaffold acts as a favorable synthetic ECM for functional bone regeneration through the physiological endochondral ossification process (i.e., through formation of cartilage intermediate), which is a new strategy of “developmental tissue engineering” to mimic natural endochondral bone repair process.  Hence, it is envisioned that the developed electrospun polycaprolactone 3D nanofibrous scaffold would be very promising for tissue engineering applications including the regenerations of bone, cartilage, and their composite tissue of osteochondral (an especially challenged tissue repair in clinics).

About The Author

Dr. Hongli Sun is an Assistant Professor in the Biomedical Engineering program at the University of South Dakota (USD).  Prior to joining the faculty at the USD, he worked as a Research Fellow in the Department of Biologic and Materials Sciences at the University of Michigan.  Dr. Sun earned his Ph.D. in Cell Biology from the Chinese Academy of Sciences (Shanghai, China) in 2007.  Inspired by the fundamental findings in stem cell and developmental biology, Dr. Sun’s research has been focusing on the development of novel stem cell/nano-biomaterials based translational strategies for challenged bone regeneration.  Dr. Sun has authored many articles in peer-reviewed journals including Biomaterials, Stem Cells, and Tissue Engineering.  In addition, he has been serving as a manuscript/grant reviewer in the fields related to bone, stem cells, and tissue engineering.

 

About The Author

Dr. Hao Fong is one of the pioneers and renowned scientists worldwide in the field of “Electrospinning and Nanofibers”.  Presently, he is a tenured Full Professor in the Department of Chemistry and Applied Biological Sciences at the South Dakota School of Mines and Technology (SDSM&T); and he is also an important faculty member in the SDSM&T’s multidisciplinary graduate programs of Materials Engineering and Science (MES), Nanoscience and Nanoengineering (NANO), and Biomedical Engineering (BME).  His highest degree is a Ph.D. earned in 1999 from the Department of Polymer Science at the University of Akron (in Ohio, USA).  Prior to joining the faculty at the SDSM&T in 2003, he worked as a guest research scientist in the Polymer Branch of the Air Force Research Laboratory (AFRL) in the Wright-Patterson Air Force Base, and as a staff research scientist in the Paffenbarger Research Center of the American Dental Association (PRC-ADA) and/or the Polymer Division at the National Institute of Standards and Technology (NIST) in Maryland, for a total of three years.  In the recent years, Dr. Hao Fong’s research interests have been focused on “The Materials-processing Technique of Electrospinning and Various Applications of Electrospun Polymer, Ceramic, Carbon/Graphite, Metallic, Composite, and Hierarchically-structured Nanofibers and/or Nanofibrous Materials”.  The applications include, but not limited to, (1) filtration/separation applications (e.g., separation of biopharmaceutical therapeutics such as proteins, purification of air/water, microfiltration, ultrafiltration, nanofiltration, and reverse osmosis), (2) energy-related applications (e.g., solar cells, batteries, fuel cells, and supercapacitors), (3) biomedical applications (e.g., tissue engineering, drug delivery, and antimicrobial wound dressing), (4) microelectronics-related applications (e.g., sensors/detectors and transistors), (5) composite applications (e.g., hybrid multi-scale composites and dental restorative composites).

Journal Reference

Adv Healthc Mater. 2015;4(15):2238-46.

Xu T¹, Miszuk JM², Zhao Y¹, Sun H², Fong H¹.

Show Affiliations

1. Program of BiomedicalEngineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
2. Program of BiomedicalEngineering, University of South Dakota, Sioux Falls, SD, 57107, USA.

Abstract

For the first time, electrospun polycaprolactone (PCL) 3D nanofibrous scaffold has been developed by an innovative and convenient approach (i.e., thermally induced nanofiber self-agglomeration followed by freeze drying), and the scaffold possesses interconnected and hierarchically structured pores including macropores with sizes up to ≈300 μm. The novel polycaprolactone 3D scaffold is soft and elastic with very high porosity of ≈96.4%, thus it is morphologically/structurally similar to natural extracellular matrix and well suited for cell functions and tissue formation. The in vitro studies reveal that the scaffold can lead to high cell viability; more importantly, it is able to promote more potent BMP2-induced chondrogenic than osteogenic differentiation of mouse bone marrow mesenchymal stem cells. Consistent to the in vitro findings, the in vivo results indicate that the electrospun polycaprolactone 3D scaffold acts as a favorable synthetic extracellular matrix for functional bone regeneration through the physiological endochondral ossification process.

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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3D fibre deposition and stereolithography techniques for the design of multifunctional nanocomposite magnetic scaffolds

Significance Statement

 Osteochondral bone injuries beyond the self-repair threshold represent a great challenge. The combination of stereolithography and 3D fibre deposition modelling represent a valuable tool to manufacture complex scaffolds. Stereolithography allows to produce thin scaffold layer, finely structured, suitable to reproduce the thin cartilage layer. However, this technique prevents to process polymeric materials incorporating a significant particulate reinforcement phase. On the other hand, 3D fibre deposition prevents to finely structure a scaffold, as the stratification thickness depends on the needle diameter. However, this technique allows to process composite materials incorporating a significant particulate reinforcement phase. This requirement is important as bone scaffolds are concerned. Therefore, by combining stereolithography and 3D fibre deposition modelling it is possible to benefit from the advantages of each single technique, and complex multimaterial scaffolds, such as scaffolds for osteochondral tissue regeneration, can be manufactured.

Poly(ethylene glycol) and poly(caprolactone) based nano-composites have been processed through stereolithography and 3D fibre deposition, respectively. Results shows that dynamic mechanical properties (e.g. storage and loss moduli) of the region of the scaffold manufactured through 3D fibre deposition reproduce those of trabecular bone. Instead, dynamic mechanical properties in compression of poly(ethylene glycol) based nano-composite mimic those of the articular cartilage. Also, the Brazilian test suggests a stable interface between the differently processed scaffold regions, and adhesion between these regions relies at least on a micromechanical interlocking.

The incorporation of a superparamagnetic nano-reinforcement phase, based on iron oxide nanoparticles encapsulated in a polymeric shell, allows for further improving the scaffold material design by offering a unique opportunity. Poly(ethylene glycol) and poly(caprolactone) based superparamagnetic scaffolds become magnetised as an external magnetic field is applied, and magnetization goes to zero as the external field is turned off. This peculiarity of superparamagnetic nanocomposite scaffolds allows to attract magnetically functionalised bioaggregates using and external magnetic field, and to release these bioaggregates on demand. This opportunity represents an important tool to guide the regeneration process of complex tissues like the osteochondral defect.

Non-degradable prosthesis based on metals, polymers and ceramics, represent the available solution to restore joint disorders. However, the life span of such approach is very limited, especially when dealing with population aging. Of course, the possibility to regenerate ostechondral bone would be the best solution. By using the reverse engineering approach to define the osteochondral defect and implementing the combination of rapid prototyping techniques, in the future it would be probably possible to manufacture customized polymer based scaffold for joint disorders.

Journal Reference

J Mater Sci Mater Med. 2015;26(10):250.

De Santis R¹, D’Amora U², Russo T², Ronca A², Gloria A², Ambrosio L³.

Show Affiliations

1. Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, V. le J.F. Kennedy 54 – Pad. 20 Mostra d’Oltremare, 80125, Naples, Italy. rosantis@unina.it.
2. Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, V. le J.F. Kennedy 54 – Pad. 20 Mostra d’Oltremare, 80125, Naples, Italy.
3. Department of Chemical Science and Materials Technology, National Research Council of Italy, Piazzale Aldo Moro 7, 00185, Rome, Italy.

Abstract

Magnetic nanocomposite scaffolds based on poly(ε-caprolactone) and poly(ethylene glycol) were fabricated by 3D fibre deposition modelling (FDM) and stereolithography techniques. In addition, hybrid coaxial and bilayer magnetic scaffolds were produced by combining such techniques. The aim of the current research was to analyse some structural and functional features of 3D magnetic scaffolds obtained by the 3D fibre deposition technique and by stereolithography as well as features of multimaterial scaffolds in the form of coaxial and bilayer structures obtained by the proper integration of such methods. The compressive mechanical behaviour of these scaffolds was investigated in a wet environment at 37 °C, and the morphological features were analysed through scanning electron microscopy (SEM) and X-ray micro-computed tomography. The capability of amagnetic scaffold to absorb magnetic nanoparticles (MNPs) in water solution was also assessed. confocal laser scanning microscopy was used to assess the in vitro biological behaviour of human mesenchymal stem cells (hMSCs) seeded on 3D structures. Results showed that a wide range of mechanical properties, covering those spanning hard and soft tissues, can be obtained by 3D FDM and stereolithography techniques. 3D virtual reconstruction and SEM showed the precision with which the scaffolds were fabricated, and a good-quality interface between poly(ε-caprolactone) and poly(ethylene glycol) based scaffolds was observed for bilayer and coaxial scaffolds. Magnetised scaffolds are capable of absorbing water solution of magnetic nanoparticles, and a preliminary information on cell adhesion and spreading of human mesenchymal stem cells was obtained without the application of an external magnetic field.

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Nicotinic acetylcholine receptors mediate donepezil-induced oligodendrocyte differentiation

Journal Reference

J Neurochem. 2015 Aug 28.

Imamura O¹, Arai M¹, Dateki M¹, Ogata T², Uchida R³, Tomoda H³, Takishima K¹.

Show Affiliations

1. Department of Biochemistry, National Defense Medical College, Tokorozawa, Saitama, Japan.
2. Department of Rehabilitation for the Movement Functions, Research Institute, National Rehabilitation Center for Persons with Disabilities, Tokorozawa, Saitama, Japan.
3. Graduate School of Pharmaceutical Sciences, Kitasato University, Minato-ku, Tokyo, Japan.

Abstract

Oligodendrocytes are the myelin-forming cells of the central nervous system (CNS). Failure of myelin development and oligodendrocyte loss results in serious human disorders, including multiple sclerosis. Here, we show that donepezil, an acetlycholinesterase inhibitor developed for the treatment of Alzheimer’s disease, can stimulate oligodendrocyte differentiation and maturation of neural stem cell-derived oligodendrocyte progenitor cells without affecting proliferation or cell viability. Transcripts for essential myelin-associated genes, such as PLP, MAG, MBP, CNPase, and MOG, in addition to transcription factors that regulate oligodendrocyte differentiation and myelination, were rapidly increased after treatment with donepezil. Furthermore, luciferase assays confirmed that both MAG and MBP promoters display increased activity upon donepezil-induced oligodendrocytes differentiation, suggesting that donepezil increases myelin gene expression mainly through enhanced transcription. We also found that the increase in the number of oligodendrocytes observed following donepezil treatment was significantly inhibited by the nicotinic acetylcholine receptor (nAChR) antagonist mecamylamine, but not by the muscarinic acetylcholine receptor antagonist scopolamine. Moreover, donepezil-induced myelin-related gene expression was suppressed by mecamylamine at both the mRNA and protein level. These results suggest that donepezil stimulates oligodendrocyte  differentiation and myelin-related gene expression via nAChRs in neural stem cell-derived oligodendrocyte progenitor cells. We show that donepezil, a drug for the treatment of Alzheimer disease, can stimulate oligodendrocyte differentiation and maturation of oligodendrocyte progenitor cells. Transcripts for essential myelin-associated genes, such as PLP, MAG, MBP, CNPase and MOG in addition to transcripton factors that regulate oligodendrocyte differentiation and myelination were rapidly increased after treatment with donepezil. These effects were partly dependent on nicotinic acetylcholine receptor (nAChR).

© 2015 International Society for Neurochemistry.

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Adipose Derived Stromal Cell (ADSC) Injections for Pain Management of Osteoarthritis in the Human Knee Joint

Significance Statement

Osteoarthritis of the knee is the most common form of arthritis that cause pain, stiffness, and decreased function, and one of leading causes of disability. Stromal vascular fraction containing large amount of stem cells and other regenerative cells, can be easily obtained from loose connective tissue that is associated with adipose tissue. The authors concluded from this clinical study that Adipose-derived stem cell therapy for patients with knee osteoarthritis  might be effective in reducing pain, and improving function. Therefore, adipose-derived stem cell treatment appears to be a good option for osteoarthritis treatment.

Journal Reference

Aesthet Surg J. 2015 Aug 3.

Fodor PB, Paulseth SG.

Dr Fodor is an Associate Clinical Professor of Plastic Surgery, UCLA Medical Center, Los Angeles, California.

Dr Paulseth is an Adjunct Instructor of Clinical Physical Therapy, Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, California.

Abstract

BACKGROUND:

This safety and feasibility study used autologous adipose-derived stromal vascular cells (the stromal vascular fraction [SVF] of adipose tissue), to treat 8 osteoarthritic knees in 6 patients of grade I to III (K-L scale) with initial pain of 4 or greater on a 10-point Visual Analog Scale (VAS).

OBJECTIVES:

The primary objective of the study was evaluation of the safety of intra-articular injection of SVF. The secondary objective was to assess initial feasibility for reduction of pain in osteoarthritic knees.

METHODS:

Adipose-derived SVF cells were obtained through enzymatic disaggregation of lipoaspirate, resuspension in 3 mL of Lactated Ringer’s Solution, and injection directly into the intra-articular space of the knee, with a mean of 14.1 million viable, nucleated SVF cells per knee. Metrics included monitoring of adverse events and preoperative to postoperative changes in the Western Ontario and McMaster Universities Arthritis Index (WOMAC), the VAS pain scale, range of motion (ROM), timed up-and-go (TUG), and MRI.

RESULTS:

No infections, acute pain flares, or other adverse events were reported. At 3-months postoperative, there was a statistically significant improvement in WOMAC and VAS scores (P < .02 and P < .001, respectively), which was maintained at 1 year. Physical therapy measurements for ROM and TUG both improved from preoperative to 3-months postoperative. Standard MRI assessment from preoperative to 3-months postoperative showed no detectable structural differences. All patients attained full activity with decreased knee pain.

CONCLUSIONS:

Autologous SVF was shown to be safe and to present a new potential therapy for reduction of pain for osteoarthritis of the knee.

LEVEL OF EVIDENCE:

4 Therapeutic.

© 2015 The American Society for Aesthetic Plastic Surgery, Inc.

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CD44 variant 6 is correlated with peritoneal dissemination and poor prognosis in patients with advanced epithelial ovarian cancer

Journal Reference

Cancer Sci. 2015;106(10):1421-8.

Tjhay F¹, Motohara T¹, Tayama S¹, Narantuya D¹, Fujimoto K¹, Guo J¹, Sakaguchi I¹, Honda R¹, Tashiro H², Katabuchi H¹.

Show Affiliations

1. Department of Obstetrics and Gynecology, Faculty of Life Sciences, Kumamoto University, Kumamoto City, Kumamoto, Japan.
2. Department of Maternal-Newborn Nursing, Kumamoto University, Kumamoto City, Kumamoto, Japan

Abstract

Cancer stem cells (CSCs) drive tumor initiation and metastasis in several types of human cancer. However, the contribution of ovarian CSCs to peritoneal metastasis remains unresolved. The cell adhesion molecule CD44 has been identified as a major marker for CSCs in solid tumors, including epithelial ovarian cancer. CD44 exists as a standard form (CD44s) and also as numerous variant isoforms (CD44v) generated by alternative mRNA splicing. Here we show that disseminated ovarian tumors in the pelvic peritoneum contain highly enriched CD44v6-positive cancer cells, which drive tumor metastasis and are responsible for tumor resistance to chemotherapy. Clinically, an increased number of CD44v6-positive cancer cells in primary tumors was associated with a shortened overall survival in stage III-IV ovarian cancer patients. Furthermore, a subpopulation of CD44v6-positive cancer cells manifested the ability to initiate tumor metastasis in the pelvic peritoneum in an in vivo mouse model, suggesting that CD44v6-positive cells show the potential to serve as metastasis-initiating cells. Thus, the peritoneal disseminated metastasis of epithelial ovarian cancer is initiated by the CD44v6-positive subpopulation, and CD44v6 expression is a biomarker for the clinical outcome of advanced ovarian cancer patients. Given that a distinct subpopulation of CD44v6-positive cancer cells plays a critical role in peritoneal metastasis, definitive treatment should target this subpopulation of CD44v6-positive cells in epithelial ovarian cancer.

© 2015 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

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