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Sheng C.,CAS Institute of Zoology | Sheng C.,Northeast Agricultural University | Zheng Q.,CAS Institute of Zoology | Zheng Q.,University of Chinese Academy of Sciences | And 23 more authors.
Cell Research | Year: 2012

Multipotent neural stem/progenitor cells hold great promise for cell therapy. The reprogramming of fibroblasts to induced pluripotent stem cells as well as mature neurons suggests a possibility to convert a terminally differentiated somatic cell into a multipotent state without first establishing pluripotency. Here, we demonstrate that Sertoli cells derived from mesoderm can be directly converted into a multipotent state that possesses neural stem/progenitor cell properties. The induced neural stem/progenitor cells (iNSCs) express multiple NSC-specific markers, exhibit a global gene-expression profile similar to normal NSCs, and are capable of self-renewal and differentiating into glia and electrophysiologically functional neurons. iNSC-derived neurons stain positive for tyrosine hydroxylase (TH), γ-aminobutyric acid, and choline acetyltransferase. In addition, iNSCs can survive and generate synapses following transplantation into the dentate gyrus. Generation of iNSCs may have important implications for disease modeling and regenerative medicine. © 2012 IBCB, SIBS, CAS All rights reserved. Source

Zou C.,Capital Medical University | Zou C.,Key Laboratory of Neurodegeneration | Zou C.,Johns Hopkins University | Chou B.-K.,Johns Hopkins University | And 11 more authors.
Stem Cells and Development | Year: 2012

Derivation of pluripotent stem cells (iPSCs) induced from somatic cell types and the subsequent genetic modifications of disease-specific or patient-specific iPSCs are crucial steps in their applications for disease modeling as well as future cell and gene therapies. Conventional procedures of these processes require co-culture with primary mouse embryonic fibroblasts (MEFs) to support self-renewal and clonal growth of human iPSCs as well as embryonic stem cells (ESCs). However, the variability of MEF quality affects the efficiencies of all these steps. Furthermore, animal sourced feeders may hinder the clinical applications of human stem cells. In order to overcome these hurdles, we established immortalized human feeder cell lines by stably expressing human telomerase reverse transcriptase, Wnt3a, and drug resistance genes in adult mesenchymal stem cells. Here, we show that these immortalized human feeders support efficient derivation of virus-free, integration-free human iPSCs and long-term expansion of human iPSCs and ESCs. Moreover, the drug-resistance feature of these feeders also supports nonviral gene transfer and expression at a high efficiency, mediated by piggyBac DNA transposition. Importantly, these human feeders exhibit superior ability over MEFs in supporting homologous recombination-mediated gene targeting in human iPSCs, allowing us to efficiently target a transgene into the AAVS1 safe harbor locus in recently derived integration-free iPSCs. Our results have great implications in disease modeling and translational applications of human iPSCs, as these engineered human cell lines provide a more efficient tool for genetic modifications and a safer alternative for supporting self-renewal of human iPSCs and ESCs. © 2012, Mary Ann Liebert, Inc. Source

Guan Y.,Capital Medical University | Guan Y.,Key Laboratory of Neurodegeneration | Du Q.-A.,Capital Medical University | Du Q.-A.,Key Laboratory of Neurodegeneration | And 10 more authors.
PLoS ONE | Year: 2013

Background: In the differentiation of mouse embryonic stem (ES) cells into neurons using the 5-stage method, cells in stage 4 are in general used as neural progenitors (NPs) because of their ability to give rise to neurons. The choice of stage 4 raises several questions about neural progenitors such as the type of cell types that are specifically considered to be neural progenitors, the exact time when these progenitors become capable of neurogenesis and whether neurogenesis is an independent and autonomous process or the result of an interaction between NP cells and the surrounding cells. Methodology/Principal Findings: In this study, we found that the confluent monolayer cells and neural sphere like cell clusters both appeared in the culture of the first 14 days and the subsequent 6 weeks. However, only the sphere cells are neural progenitors that give rise to neurons and astrocytes. The NP cells require 14 days to mature into neural lineages fully capable of differentiation. We also found that although the confluent monolayer cells do not undergo neurogenesis, they play a crucial role in the growth, differentiation, and apoptosis of the sphere cells, during the first 14 days and long term culture, by secreted factors and direct cell to cell contact. Conclusions/Significance: The sphere cells in stage 4 are more committed to developing into neural progenitors than monolayer cells. Interaction between the monolayer cells and sphere cells is important in the development of stage 4 cell characteristics. © 2013 Guan et al. Source

Zou C.,Capital Medical University | Zou C.,Key Laboratory of Neurodegeneration | Zou C.,Guangxi Medical University | Wang S.,Capital Medical University | And 4 more authors.
Cornea | Year: 2012

Purpose: The purpose of this study was to investigate the ultrastructural corneal changes of chronic diabetic monkeys and explore the relationship between advanced glycation end products and ultrastructural changes in diabetic corneas. Methods: A total of 8 cynomolgus monkeys were used in this experiment. Four monkeys were induced into insulin-dependent diabetes mellitus for 4 years. Four age-matched healthy monkeys were used as the controls. Ultrathin sections obtained from the corneas were examined by transmission electron microscopy. Results: Advanced glycation end product immunoreactivity was observed in the epithelial cells, epithelial basement membrane, and stromal keratocytes of diabetic corneas, whereas advanced glycation end product immunoreactivity was not found in the corresponding area in normal corneas. Abnormal collagen fibril bundles of variable thickness were identified in corneal stroma in all diabetic monkeys. Epithelial and endothelial cell degeneration was also observed in 1 diabetic monkey. Conclusions: Abnormal aggregates of collagen fibrils in stromal matrix were common among long-term diabetic monkeys, and the formation of the abnormal collagen fibril aggregates might result from excessive nonenzymatic glycosylation. Copyright © 2012 by Lippincott Williams and Wilkins. Source

Sun W.,Anhui Medical University | Zuo J.,Anhui Medical University | Ren Z.,Capital Medical University | Ren Z.,Key Laboratory of Neurodegeneration | And 6 more authors.
International Journal of Essential Oil Therapeutics | Year: 2010

Olfaction not only plays a key role in the daily life of animals, but also closely relates to neural network plasticity. Our previous behavior studies found that eugenol can improve spatial memory in mice via olfactory inhalation. In the present study, we confirmed this phenomenon by Morris water maze testing and further explored the change of initial expression of olfactory information-odorant receptor gene following eugenol intervention in vivo and in vitro.The results suggested that the effect of eugenol may be mediated by mOR-EG gene expression after olfactory inhalation. Thus, our data may provide an original clue to interpret the action of the holistic therapy-aromatherapy. These studies demonstrated that olfactory signal pathway may be used for an invasive way to intervene in the learning and memory related diseases. Interestingly, our data also showed that an odorant experience might improve the sensitivity of this odorant perception by promoting the specific OR gene expression. Our research provides a new option to elucidate the phenomenon that odorant experience improves olfactory perception. Source

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