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AIM: To investigate the reparative effect of extracellular vesicles (EVs) derived from H9 human embryonic stem cells (H9-hESCs) on endometrial injury. METHODS: EVs were isolated from the culture supernatant of H9-hESCs and characterized. A mouse model of endometrial injury was established, with bilateral uterine divisions into an EVs experimental group and a PBS control group. EVs and PBS were injected respectively. Histological changes in the endometrium were assessed using HE staining, and proliferating cell nuclear antigen (PCNA) expression was analyzed via immunohistochemistry. The impact of EVs on the proliferation of human endometrial stromal cells (hEndoSCs) was evaluated using EdU staining and Western blot. RESULTS: H9-hESCs-EVs exhibited a membrane-structured nanobody with a particle size of (144.7±2.1) nm and expressed characteristic proteins CD63 and TSG101. Compared to the PBS control group, the EVs group showed increased endometrial tissue morphology, thickness, and gland numbers. The average optical density of PCNA expression significantly increased in the EVs group compared to the PBS group (P<0. 05). Results from EdU staining and Western blot demonstrated that H9-hESCs-EVs promoted hEndoSC proliferation, with a positive correlation observed between H9-hESCs-EVs and EVs protein concentration (P<0. 05). CONCLUSION: H9-hESCs-EVs enhance the repair of endometrial injury by stimulating the proliferation of endometrial stromal cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: Autoimmune regulator gene (Aire) and Wnt signaling pathway play an important role in the maintenance and differentiation of mouse embryonic stem cell pluripotency. However, whether the Wnt signal and Aire are involved in the differentiation of embryonic stem cells to thymic epithelial progenitor cells remains poorly understood. OBJECTIVE: To investigate the relationship of the Wnt signaling pathway and Aire with the differentiation of embryonic stem cells. METHODS: A two-step differentiation method was used to induce mouse embryonic stem cells to differentiate into endoderm and then into thymic epithelial progenitor cells. Mouse embryonic stem cells were infected with Aire shRNA lentivirus, and monoclonal stable strains were screened by puromycin. Mouse embryonic stem cells were collected on days 0, 3 and 10 of the directed induction of differentiation after the induced differentiation by the two-step differentiation method. Cellular immunofluorescence, flow cytometry, western blot assay, and real-time qPCR were used to detect the expression changes of related genes and proteins. RESULTS AND CONCLUSION: (1) Immunofluorescence staining showed positive expression of SSEA1 and OCT4 on day 0 of targeted induction of differentiation. (2) Immunofluorescence staining showed double-positive expression of SOX17 and FOXA2 on day 3 of targeted induction of differentiation. (3) Flow cytometry results showed positive expression of EPCAM1, K5 and K8 on day 10 of targeted induction of differentiation. (4) Compared with undifferentiated mouse embryonic stem cells, the expressions of Wnt7a, β-catenin, and Gsk-3β proteins were elevated, and the expression level of Aire protein was decreased in induced differentiated thymic epithelial progenitor cells. (5) Compared with undifferentiated mouse embryonic stem cells, the expressions of Wnt7a, β-catenin, Gsk-3β and Aire mRNA were elevated in thymic epithelial progenitor cells. (6) Compared with normal cultured mouse embryonic stem cells and their ultimately differentiated thymic epithelial progenitor cells, the expression levels of Wnt7a, β-catenin and Gsk-3β proteins were reduced in mouse embryonic stem cells with knockdown of Aire genes and their final differentiated thymic epithelial progenitor cells. In conclusion, the Wnt signaling pathway and Aire are jointly involved in the process of targeted induction of differentiation of mouse embryonic stem cells into mouse thymic epithelial progenitor cells. [ABSTRACT FROM AUTHOR]

Although blood protection technologies such as autologous blood transfusion can alleviate to some extent the short supply of clinical blood, red blood cells are still in great demand as the main blood component. This problem can be solved by the safe production of red blood cells in vitro. At present, mature erythrocytes can be differentiated from embryonic stem cells, human induced pluripotent stem cells, umbilical cord blood, peripheral blood, and immortalized erythroid progenitor cell lines. This article reviews the sources and applications of red blood cells produced in vitro, and analyzes the current challenges, in order to provide new insights for blood transfusion therapy.

Since the establishment of the first human diploid cell line derived from aborted fetal tissue in the 1960s, human embryoderived cells have been widely used in biomedical field and significantly contributes to improving human health. In recent years, human pluripotent stem cells, including human embryonic stem cells (hESCs), have shown great therapeutic potential in regenerative medicine, and thus received great attention from governments and the public. However, due to various factors such as history, culture, religious beliefs, ethics and morality, research and application involving human embryo-derived cells have been controversial worldwide. This study explores the history and progress of human embryo-derived cells in the field of biomedicine, and analyzes the evolution of regulatory systems in different countries, with the aim of facilitating the improvement of China's regulatory framework and technical requirements in this field. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cell replacement therapy is a very promising approach to treating Parkinson’s disease. The current main regimen for neural differentiation of human pluripotent stem cells is the “dual SMAD” inhibition regimen, which uses blockade of glycogen synthase kinase 3β to activate WNT pathway signaling, followed by a combination of hedgehog signaling and bone morphogenetic protein signaling regulation to precisely control the specific fate of human pluripotent stem cells from the basal to the parietal regions. Macrophage migration inhibitory factor (MIF), a class of pleiotropic immunomodulatory cytokines with a unique structure, has been shown to be important for neural development and differentiation in several studies. However, whether MIF is involved in the induction of stem cell differentiation is unknown. OBJECTIVE: On the basis of the “dual SMAD” inhibition regimen, different concentrations of MIF and its inhibitor (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isothiazoleacetic acid methyl ester (ISO-1) were added to the culture medium to observe its effect on the differentiation of human embryonic stem cells into midbrain dopaminergic progenitor cells, to find a new way to solve the problem of heterogeneity during differentiation of human embryonic stem cells into midbrain dopaminergic progenitor cells. METHODS: CCK8 assay was performed to detect the survival of human embryonic stem cells cultured with the addition of different concentrations of MIF and ISO-1. The expression of MIF receptors CD74, CD44 and CXCR7 on human embryonic stem cells was detected by immunofluorescence. The expression levels of ventral midbrain markers LMX1A, FOXA2, EN1, forebrain marker FOXG1, hindbrain marker HOXA2, midbrain substrate marker PAX6 and transcription factor SOX6 of Wnt1/β-catenin signaling pathway were determined by RT-qPCR and western blotting, respectively, 16 days after differentiation of embryonic stem cells levels. Meanwhile, the expression levels of LMX1A, FOXA2, EN1 and MAP2 were measured by immunofluorescence assay. The expression of LMX1A, FOXA2, TH and GIRK2 in dopaminergic neurons was determined by immunofluorescence assay after continuing the differentiation of embryonic stem cells until day 42. RESULTS AND CONCLUSION: (1) MIF was expressed in human embryonic stem cells, and its associated receptors CD44 and CXCR7 were also expressed, but CD74 expression did not occur. (2) The addition of MIF promoted the protein expression of LMX1, FOXA2, and EN1, and promoted the gene expression of LMX1 and FOXA2. It also significantly inhibited the gene and protein expression of FOXG1 and HOXA2 and PAX6, effectively suppressing the heterogeneity of differentiation. (3) The addition of MIF did not result in high expression of SOX6 in dopaminergic neural progenitors as expected, but rather decreased expression at the gene level, while its inhibitor ISO-1 caused a mild increase in SOX6 expression at the gene level. (4) The present study demonstrates that MIF plays an important role in the dopaminergic differentiation potential and ventral midbrain fate determination of human embryonic stem cells and that MIF intervention further optimizes the regional localization of neural induction. [ABSTRACT FROM AUTHOR]

BACKGROUND: The cellular activity of Lin28A can be influenced in several ways, including the self-renewal of embryonic stem cells, somatic cell reprogramming, individual growth and development, tissue metabolism, and carcinogenic consequences. However, neither domestically nor internationally have its effects on periodontal ligament stem cell ability to differentiate into osteoblasts been well explored; the underlying mechanisms are not known. OBJECTIVE: To investigate the impact of Lin28A on periodontal ligament stem cell capacity for osteogenic differentiation. METHODS: By using conventional enzyme digestion, periodontal ligament stem cells were extracted and cultured. The distribution of Lin28A in these cells and the differential expression of Lin28A at different time points of osteogenic induction were detected by qRT-PCR. Lentiviral vectors with Lin28A overexpression and interference expression were constructed and transfected into periodontal ligament stem cells. Fluorescence microscopy was used to observe the transfection effect. qRT-PCR was used to verify the expression difference of Lin28A after lentivirus transfection. The expression levels of osteoblastic genes alkaline phosphatase, Runt-related transcription factor 2 and osteopontin, alkaline phosphatase staining and alizarin red staining results were further detected from positive and negative aspects. The protein expression level of Runt-related transcription factor 2 was detected by western blot assay. Bioinformatics techniques and dual luciferase were used to predict and verify the relationship between Lin28A-related let-7 family members. The periodontal ligament stem cells differentially expressing Lin28A were cultured through osteoblastic induction, and the miRNA with the most obvious expression change during osteoblastic differentiation was determined. RESULTS AND CONCLUSION: (1) Lin28A was enriched in the nucleus of periodontal ligament stem cells, and the expression of Lin28A increased at different time points after osteogenic induction. (2) In the periodontal ligament stem cell models with Lin28A overexpression, alkaline phosphatase staining and alizarin red staining were significantly deeper than those in the blank control group; the expression levels of alkaline phosphatase, Runt-related transcription factor 2 and osteopontin were increased 3.3, 5.1 and 2.2 times, respectively, compared with the blank ones (P < 0.01). In cell models that interfered with Lin28A expression, alkaline phosphatase staining and alizarin red staining were also decreased compared with the control group. The levels of alkaline phosphatase, Runt-related transcription factor 2 and osteopontin decreased 0.19-fold, 0.61-fold and 0.1-fold, respectively (P < 0.01). (3) The protein level of Runt-related transcription factor 2 was consistent with the mRNA difference tendency. The expression of Runt-related transcription factor 2 was increased in the overexpression group and decreased in the interference group. (4) Bioinformatics predicted that Lin28A was associated with eight let-7 family members, which were let-7a, let-7b, let-7c, let-7d, let-7e, let-7f, let-7g and let-7i, respectively. After screening, the expression levels of let-7a and let-7c showed significant changes with Lin28A expression, and let-7a showed the most significant trend. Double luciferase binding assay confirmed that let-7a was directly bound to the 3'-UTR of Lin28A and was involved in the osteogenic differentiation of periodontal ligament stem cells. (5) The results suggested that Lin28A was involved in the regulation of osteogenic differentiation of periodontal ligament stem cells, with a positive correlation. That was, overexpression of Lin28A promoted the osteogenic ability of periodontal ligament stem cells, and the osteogenic ability of periodontal ligament stem cells was weakened after interference of Lin28A expression. The osteogenic differentiation of periodontal ligament stem cells was regulated by Lin28A . [ABSTRACT FROM AUTHOR]

N6-methyladenosine （m6A） is one of the universal epigenetic modifications of eukaryotic ribonucleic acid （RNA）, and involves in the regulation of a variety of cellular processes. As the most abundant RNA in cells-ribosomal RNA （rRNA）, its function and mechanism of m6A modification remained to be revealed. Methyltransferase-like protein 5（METTL5） is a methyltransferase that specifically mediates the m6A modification of ribosomal 18S rRNA in A1832 site, m6A modification at this site could affect the ribosomal translation function through changing the conformation of the ribosomal decoding center. METTL5 plays important roles in the occurrence and development of malignant tumors （liver cancer, breast cancer, gastric cancer, etc.）, abnormal brain development （microcephaly, mental retardation, etc.）, abnormal differentiation of embryonic stem cells and cardiac hypertrophy. The review focuses on the research progress of METTL5 in these aspects. [ABSTRACT FROM AUTHOR]

AIM: To develop a glioma invasion model using human brain organoids, and to assess the invasive potential of tumor cells utilizing this model. METHODS: Human embryonic stem cells (ESCs) -derived brain organoids were generated through neural-directed induction. These brain organoids were then co-cultured with human glioma stem cells (GSCs), and a glioma invasion model was established. Subsequently, the invasive depth of various GSCs within the brain organoids was assessed to determine their invasive capacity. RESULTS: (1) On day 31, human ESCs were in‑ duced to differentiate into numerous neuroepithelial bud structures. Immunofluorescence staining confirmed the expression of neural stem cell-specific proteins Sox2, Pax6 and nestin, indicating the formation of brain organoids. (2) In the co-cul‑ ture of brain organoids with GSCs, invasion and growth of the GSCs were observed within the brain organoids, indicating successful establishment of a model for glioma invasion. (3) Variations were observed in the invasive depth of different GSCs infiltrating the brain organoids. CONCLUSION: A glioma invasion model using ESCs-derived human brain organoids is developed, which is expected to serve as a valuable tool for assessing the invasive potential of GSCs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Stem cells play an important role in liver regeneration and self-repair ability, which is of great significance for clinical diagnosis and treatment of liver diseases. OBJECTIVE: To summarize the current clinical trials and basic research in this field in and outside China, review the types of stem cells used to treat liver diseases in the past, and the treatment programs of various types of stem cells for various types of liver diseases, outline the clinical application prospects of various types of stem cells in the future application of liver diseases, and provide a research basis for the treatment of clinical liver diseases. METHODS: Using “stem cells, mesenchymal stem cells, hepatic stem cell, embryonic stem cell, induced pluripotent stem cell, hematopoietic stem cell, hepatopathy, non-alcoholic fatty liver disease, liver cirrhosis, liver failure, autoimmune hepatitis, hepatocellular carcinoma” as search words, the relevant articles in PubMed, Web of Science and Wiley e-journal databases were searched, and 71 articles were selected for review according to the inclusion criteria. RESULTS AND CONCLUSION: (1) Mesenchymal stem cells, liver stem cells, embryonic stem cells, induced pluripotent stem cells and hematopoietic stem cells are the main stem cells for the treatment of liver diseases. The characteristics, expression period and application of these stem cells in differentiation after liver injury are summarized in this paper. (2) In general, mesenchymal stem cells can repair liver through exosomes, matrix metalloproteinase and anti-inflammatory response. Liver stem cells can differentiate liver oval cells and small hepatocellular progenitor cells to form mature liver cells and promote liver injury repair. Induced pluripotent stem cells, embryonic stem cells and hematopoietic stem cells can transform into mature hepatocytes through rapid proliferation and differentiation. (3) The treatment of various liver diseases by stem cells is mainly achieved by inducing endogenous cell proliferation, immune regulation, inhibiting inflammation, promoting liver cell regeneration and repairing damaged tissues. (4) On the whole, at present, mesenchymal stem cells are relatively easy to obtain, have the broadest application prospects, and do not involve ethical issues. They are transforming from preclinical research to clinical research. Because mesenchymal stem cells can differentiate into various adult stem cells, they have the advantages of low immunogenicity, strong self-proliferation and differentiation ability. Especially for the treatment of immune hepatitis, liver cirrhosis and hepatocellular carcinoma and other liver diseases, mesenchymal stem cells have the most ideal effect. (5) Induced pluripotent stem cells are more effective in the treatment of end-stage liver disease because they can differentiate into specific somatic cells and hepatocytes without immune rejection. (6) However, stem cell transplantation can induce acute rejection, such as diarrhea, jaundice, and skin rashes. Poor histocompatibility between donors and recipients can easily lead to adverse reactions such as graft-versus-host reactions. After stem cell transplantation, the use of stem cells and its clinical safety assessment still need the support of more clinical trials and evidence-based medicine data. [ABSTRACT FROM AUTHOR]

An increasing number of studies focus on the molecular structure and function of mechanically activated ion channel Piezo in recent years. It has been well known that intracellular and extracellular mechanical stimulation could act through Piezo channels to modulate diverse cellular functions such as migration, proliferation, differentiation and development. Embryonic stem cells, mesenchymal stem cells, intestinal stem cells and other type of stem cells can detect and respond to mechanical stimulation in surrounding microenvironment. Emerged as key molecular detectors of mechanical forces, Piezo channels play a key bridging role in converting mechanical stimuli into electrochemical signals, and are suggested to be involved in the regulation of proliferation, migration, differentiation and apoptosis of stem cells by activating different signal transduction pathways. In this review, the involvement of mechanosensitive ion channel Piezo in the regulation of stem cells biological activities were summarized, and the potential significance of Piezo channels targeted stem cell therapy was also discussed. [ABSTRACT FROM AUTHOR]

Objective To explore the role of S100A9 in the apical-basal polarity (ABP) and neural tube formation during the differentiation of embryonic stem cells (ESCs) into neural progenitor cells (NPCs) in vitro. Methods Immunofluorescence assay was used to observe the luminal arrangement, expression of Nestin and paired box protein 6 (Pax-6), and localization of S100A9, N-cadherin and Zonula occludens 1 (ZO-1) on days 1, 2, 3 and 6 of the ESCs differentiation into NPCs. In addition, the ESCs were treated with S100A9-downregulation lentivirus as well as subsequential exogenous S100A9 recombinant protein, then the localization changes of N-cadherin and ZO-1 were detected. The S100A9 expression in different time points during ESCs differentiation process was measured by Western blotting, and the effects of S100A9 on Notch1 and downstream centromere binding factor 1 (CBF1) were also tested. Results Nestin and Pax-6 were positively expressed after ESCs differentiation for 3 d, N-cadherin and ZO-1 were gathered at the apical side and presented the characteristic neural rosette structure of ABP, and the neural tubes were formed on day 6. The expression of S100A9 was upregulated significantly from day 3 after differentiation (P < 0.01) and was located on the apical side. Although ESCs were still able to differentiate into NPCs after down-regulation of S100A9, the number of neural rosettes was greatly reduced (P < 0.01), which could be partially restored by supplement of exogenous S100A9 recombinant protein (P < 0.01). Furthermore, declined S100A9 inhibited the expression of Notch 1 and downstream CBF1 during differentiation. Conclusion S100A9 may contribute to the ABP and the formation of neural lumen during the differentiation of ESCs into NPCs by regulating Notch 1/CBF1.

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: As the research progresses, the increasing evidence has shown that mesenchymal stem cells mainly exert their therapeutic effects through paracrine mechanisms, and extracellular vesicles are an important paracrine component of cells. Therefore, extracellular vesicles have attracted considerable interest, especially in the cardiovascular field. OBJECTIVE: To review the progress in the treatment of myocardial infarction with extracellular vesicles and explore the clinical application prospects of extracellular vesicles. METHODS: The relevant articles were searched from CNKI and PubMed databases by computer. The search terms were “extracellular vesicles, myocardial infarction, cardiac repair” in Chinese and “extracellular vesicles, mesenchymal stem cell, embryonic stem cell, induced pluripotent stem cell, cardiomyocyte, target, myocardial infarction, cardiac repair” in English. The time was limited from 2016 to 2021. Finally, 70 articles were included for this review. RESULTS AND CONCLUSION: (1) At present, many studies have successfully used extracellular vesicles to treat myocardial infarction and obtained considerable efficacy. Stem cells, such as mesenchymal stem cells, and some differentiated cell-derived extracellular vesicles can help the infarcted heart maintain normal physiological structure and function by inhibiting apoptosis of hypoxic cardiomyocytes, promoting angiogenesis in the infarct border zone, inhibiting the inflammation or reducing the fibrosis. (2) The mechanism of some cargoes carried by extracellular vesicles for the repair of myocardial infarction has been clarified, of which many microribonucleic acids play important roles in some pivotal cardiac repair signaling pathways, such as miR-21, miR-486-5p, and miR-144. Therefore, more studies are no longer limited to the application of naturally derived extracellular vesicles, but further load therapeutic drugs in extracellular vesicles or modify the membrane components of extracellular vesicles, thereby improving their myocardium targeting ability and cardiac repair potential. K [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of the Chinese Society of Animal Science is the property of Chinese Society of Animal Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Stem cell therapy has great clinical application potential. Stem cell donor needs to be screened for infectious and genetic diseases before implantation, but some important factors related to lifestyle are often overlooked, especially smoking. For many diseases, smoking is a risk factor. With the increasing use of e-cigarettes, nicotine exposure is becoming serious and widespread. OBJECTIVE: To describe and analyze the effects of nicotine exposure on various types of stem cells. METHODS: Articles were searched on PubMed and CNKI databases published between 1806 and 2021. The search terms were “nicotine, tobacco smoking, stem cells therapy, embryonic stem cells, mesenchymal stem cells, induced pluripotent stem cells, periodontal ligament-derived stem cells” in Chinese and English. A total of 59 articles were selected according to the inclusion and exclusion criteria and summarized. RESULTS AND CONCLUSION: Nicotine activates nicotinic acetylcholine receptors in embryonic stem cells, mesenchymal stem cells, induced pluripotent stem cells and periodontal membrane stem cells through a variety of mechanisms to affect their proliferation, differentiation, migration and apoptosis. At present, although the research on the effect of nicotine on stem cells is facing severe challenges, it is very necessary to study the effect of nicotine on stem cells, because “healthy stem cells” are the prerequisite for stem cell therapy. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cell therapy is a promising branch of medical tissue engineering and regenerative medicine, and which is a good strategy for the repair of peripheral nerve injury. OBJECTIVE: To review the common repair methods of peripheral nerve injury, several cells commonly used for peripheral nerve injury repair and the mechanism of cell therapy to promote peripheral nerve injury repair. METHODS: The key words were “cell therapy, stem cell therapy, peripheral nerve injury, repair” in English and Chinese. Wanfang, CNKI and PubMed databases were retrieved for the articles concerning the cell therapy in the repair of peripheral nerve injury published from 2010 to 2020. After excluding repetitive, old and irrelevant articles, 45 eligible articles were further analyzed. RESULTS AND CONCLUSION: (1) After summarizing the common repair methods of peripheral nerve injury, such as conventional direct suture, nerve graft, and nerve transfer, and the advantages and disadvantages of each method were described. (2) Several kinds of cells commonly used for peripheral nerve injury repair, such as Schwann cells, olfactory ensheathing cells, and embryonic stem cells, were reviewed, and the defects of various cells were pointed out. (3) The mechanism of cell therapy to promote peripheral nerve injury repair was summarized, which was mainly manifested in the application of Schwann cells or Schwann cells-like cells, secretion of neurotrophic factors, extracellular matrix molecules and cell adhesion molecule, and promotion of myelin formation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Transplantation therapy after the directional differentiation of induced pluripotent stem cells can solve the immune elimination and ethical problems, and directional differentiation of induced pluripotent stem cells into cardiomyocytes provides the possibility of cardiomyocyte regeneration research. OBJECTIVE: To detect the electrophysiological function of cardiomyocytes differentiated from induced pluripotent stem cells. METHODS: By culturing induced pluripotent stem cells in vitro, direct suspension culture and differentiation medium were used to induce induced pluripotent stem cells to form embryoid bodies. Cell growth was observed and formation time, number and contraction rate of cardiomyocytes were recorded. The electrophysiological characteristics of cardiomyocytes were detected by Axon Axopatch 200B single probe ultra-low noise patch clamp amplifier and MED64 multi-electrode array system. The responsiveness of differentiated cardiomyocytes to isoproterenol was observed. Cardiac troponin T expression levels in differentiated cardiomyocytes were detected by immunofluorescence. RESULTS AND CONCLUSION: (1) The growth characteristics of induced pluripotent stem cells were similar to embryonic stem cells, resembling a bird’s nest and growing like a colony. (2) In the differentiation medium culture, induced pluripotent stem cells aggregated to form embryoid bodies of different sizes after 5 days of suspension culture. During the adherent growth of embryoid bodies, up to 10% of the colonies appeared beating cardiomyocytes, and the beating rate on the 20th and 25th days was significantly higher than other time points (P < 0.05). (3) Action potentials of ventricular, atrial and sinoatrial nodular cells were observed in induced pluripotent stem cells differentiated cardiomyocytes. (4) Isoproterenol could increase the spontaneous beat frequency of cardiomyocytes differentiated from induced pluripotent stem cells. (5) Cellular immunofluorescence indicated that cardiomyocytes differentiated from induced pluripotent stem cells were positive for cardiac troponin T. (6) The results confirm that cardiomyocytes differentiated from induced pluripotent stem cells have sinoatrial-like, atrial-like and ventricular-like action potentials, and have adrenaline signal transduction. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of Notch signaling pathways on differentiation of mouse embryonic stem cells(ESC) into haematopoietic stem or progenitor cells(HSC/HPC). Methods 1)incubate mouse embryoid body cells and divide the embryonic stem cells into five groups as EB group,control group,Jagged-1 group, DAPT group and Jagged-1-DAPT group. 2)detect the phenotype of HSC/HPC by flow cytometry. 3)The expression of Notch signaling pathway, mouse embryonic stem cell phenotype and HSC/HPC phenotype were detected by RT-PCR. Results 1)the number of embryonic stem cells in Jagged-1 group was significantly more than that in control group and Jagged-DAPT group(P＜0.05);2)the number of HSC/HPC in Jagged-1-DAPT group was significantly more than that in control group and in Jagged-1 group(P＜0.05); 3)the expression of Notch1, Notch2 and Notch4 mRNA in Jagged-1 group was significantly higher than that in control group(P＜0.05), 4)the expression of Notch1 and Notch4 mRNA in DAPT group and Jagged-1-DAPT group was lower than that in control group(P＜0.05). Conclusions Jagged-1 activation of Notch signaling pathway potentially inhibits ESC differentiation into HSC/HPC in mice model.

BACKGROUND: Embryonic neural stem cells can differentiate into neurons and glial cells. In practical applications, we hope that neural stem cells will differentiate into neurons more. Therefore, it is very important to study the mechanism of directional differentiation of neural stem cells into neurons. DNA topoisomerase II is a type of nucleoprotein widely present in organisms and plays an important role in life activities such as DNA replication, repair, transcription, recombination and chromosome separation. OBJECTIVE: To explore the expression and significance of DNA topoisomerase II in neural stem cells and their directional differentiation into neurons. METHODS: Neural stem cells were isolated from cerebral cortex of ICR mice (E12.5 d) and cultured. The single cells after digestion were inoculated in a petri dish at 5×108 L-1 after matting with Matrigel. The conditioned medium of neurogenic differentiation containing B27, N2 and 10 μg/L glial cell line derived neurotrophic factor was added. At 1, 2, and 3 days after culture, the expression of DNA topoisomerase II α and β was detected by immunocytochemistry, western blot assay, and real time-quantitative PCR. RESULTS AND CONCLUSION: (1) The number of DNA topoisomerase IIα-positive cells in neurospheres was large and evenly distributed, and the number of positive cells after induced differentiation was reduced. The number of DNA topoisomerase IIβ-positive cells in neurospheres was relatively small, mainly distributed in the center of neurospheres. After induced differentiation, the number of positive cells began to increase gradually. At 2 days, the expression reached a peak, and then showed a decreasing trend. (2) The expression of DNA topoisomerase IIα protein and mRNA in neurospheres was high and gradually decreased after the differentiation into neurons. The expression of DNA topoisomerase IIβ protein and mRNA in neurospheres was low and significantly increased after neuronal differentiation. (3) Through experiments, it is concluded that DNA topoisomerase IIβ participates in the directional differentiation of neural stem cells into neurons. [ABSTRACT FROM AUTHOR]

BACKGROUND: The repair of cartilage defects such as ears, noses, throats, trachea and joints has always been one of the difficulties faced by clinical treatment. The emergence of cartilage tissue engineering has become a popular development direction for cartilage repair, in which seed cells are used to construct tissue engineered cartilage key. OBJECTIVE: This article intends to review the characteristics of various types of seed cells, their application in cartilage tissue engineering, and existing problems, and to bring new ideas to clinical transformation. METHODS: The first author searched the relevant articles of CNKI, Wanfang, PubMed, Scopus and Web of Science databases, using “seed cells; tissue engineering; chondrocytes; stem cells; co-cultivation” as the Chinese and English search terms. Finally, 70 articles that met the criteria were selected for review. RESULTS AND CONCLUSION: (1) Current experimental research on cartilage tissue engineering has achieved a lot of results, but the problem of selecting seed cells is still a big problem. Chondrocytes, various types of mesenchymal stem cells, embryonic stem cells, and induced pluripotent stem cells have different degrees of advantages, but also face different challenges. (2) The discovery, development and application of various seed cells have promoted the progress of cartilage tissue engineering. Among them, the method of co-culture of chondrocytes and stem cells is currently a popular and promising seed choice for research. [ABSTRACT FROM AUTHOR]

BACKGROUND: Induced pluripotent stem cells (iPSCs) without virus vector integration can be successfully induced by small molecule compounds and plasmid transfection. Similar to embryonic stem cells, iPSCs can differentiate freely into hematopoietic progenitor cells. However, it is not clear whether exogenous factors and human cells from different sources affect the differentiation of iPSCs and hematopoietic progenitor cells. OBJECTIVE: To compare the gene expression differences between iPSCs of different cell sources and embryoid bodies of embryonic stem cells, so as to explore the clinical transformation of iPSCs. METHODS: The iPSCs and human embryonic stem cells were constructed from amniotic cells-derived cells and urine cells-derived cells. The different days of embryoid bodies were collected to test the expression of pluripotent genes Oct4, Sox2 and Nanog, endoderm marker gene GATA4, mesoderm marker gene MSX1, ectoderm marker gene PAX6, hematopoietic stem cell marker genes CD34/CD43. RESULTS AND CONCLUSION: (1) The expression of Oct4/Sox2/Nanog in embryoid bodies from amniotic fluid cells derived iPSCs was almost undetectable at 8 days, which was different from urine cells derived iPSCs and embryoid bodies embryonic stem cells. They could sustain expression until 16 days. (2) The expression peak of GATA4/MSX1/PAX6 in embryoid bodies from amniotic fluid cells derived iPSCs was at 4 days, and sustained expression at 8-12 days. The expression peak of GATA4/MSX1/PAX6 in embryoid bodies from urine cells derived iPSCs and embryonic stem cells was at 4-8 days, and sustained expression at 12-16 days. The expression level of three layer-differentiation markers for embryoid bodies from urine cells derived iPSCs were significantly higher than iPSCs from amniotic fluid cells and embryonic stem cells. (3) At 12 days, the ratio of hematopoietic stem cell was the most in embryoid bodies from amniotic fluid cells and urine cells derived iPSCs. However, the ratio in the embryoid bodies from embryonic stem cells was at 4 days. The hematopoietic stem cell ratio was higher in embryoid bodies from urine cells derived iPSCs than that in amniotic fluid cells and embryonic stem cells. (4) Embryoid bodies from different cells derived iPSCs and embryonic stem cells all had pluripotency and the ability of three layer-differentiation, but they were distinctive. Urine cells derived iPSCs may replace embryonic stem cells as hematopoietic cell differentiation model in vitro. [ABSTRACT FROM AUTHOR]

Objective To investigate the therapeutic effect of transplanted Nurr1 gene-modified embryo midbrain neural stem cells in Parkinson's rats. Methods 1. Establishment of Parkinson's disease animal model in SD rats. 2. Primary culture of embryo midbrain neural stem cells (NCSs) and Nurr1 gene-modified neural stem cells. 3. Grouping: sham operation group (sham group), Transplanted neural stem cell group (NCS group), transplanted Nurr1 gene-modified neural stem cells group (NNCS group). 4. At 3 weeks, 6 weeks, 9 weeks, and 12 weeks after the transplantation, the behavioral tests of rats in each group were performed to observe the improvement of symptoms in each group. 5. After 12 weeks of transplantation, the expression of Nurr1, TH protein and Nurr1 fluorescence were detected in each group. Results 1. Primary cultured neural stem cells, and successfully overexpressed Nurr1 in neural stem cells. 2. Overexpression of Nurr1 could promote the transformation of neural stem cells into dopaminergic neurons (P < 0.05), which was confirmed by immunofluorescence and Western Blot. 3. Transplantation of NNCS can effectively improve the symptoms of rats with Parkinson's (P < 0.05). 4. After transplantation, Nurr1 can promote the transformation of neural stem cells into dopaminergic neurons, greatly improve the survival of transplanted neural stem cells and achieve better therapeutic effect. Conclusion Nurr1 can promote the transformation of neural stem cells into dopaminergic neurons. Transplantation of overexpression of Nurr1 neural stem cells can effectively treat Parkinson's rats. [ABSTRACT FROM AUTHOR]

BACKGROUND: Induced pluripotent stem cells have many advantages such as differentiation totipotency, wide source, easy access and no ethical constraints, so they rapidly become promising seed cells in the field of tissue engineering. OBJECTIVE: To review the progress of induced pluripotent stem cells in bone surgery tissue engineering. METHODS: The electronic database PubMed was searched by the first author. The key words were “iPSCs, osteanagenesis, tendon, spinal cord, spinal cord, tissue engineering, regenarative medicine”. The literature published from 2000 to 2020 was searched. A total of 50 articles were selected as references for review, screening the documents with strong relevance and excluding those with little content. RESULTS AND CONCLUSION: Compared with mesenchymal stem cells and embryonic stem cells, induced pluripotent stem cells have many advantages, such as wide source, easy access, no ethical constraints and controllable gene instability, reducing immune rejection. Induced pluripotent stem cells technology in bone surgery tissue engineering research showed satisfactory results. Key words: stem cells; induced pluripotent stem cells; tendon; bone; cartilage; spinal cord; tissue engineering; review [ABSTRACT FROM AUTHOR]

BACKGROUND: Stem cell-derived exosomes carry biologically active substances such as miRNAs and proteins that contribute to intercellular signal transduction, which have an important and positive impact on the nerve repair. They have a therapeutic effect similar to stem cell transplantation and can be used to replace stem cell transplantation for treating peripheral nerve injury. OBJECTIVE: To summarize the application of exosomes from stem cells in the treatment of peripheral nerve injury, so as to provide reference and basis for exosomes applied in the treatment of peripheral nerve injury. METHODS: Articles in PubMed database from 2000 to 2020 were searched using the search terms of “peripheral nerve, injury, damage, stem cells, embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, exosomes, repair, regenerate.” Articles in databases of CNKI, VIP and WANFANG from 2000 to 2020 were retrieved with the search terms of “peripheral nerve, injury, damage, stem cells, embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, exosomes, repair, regenerate.” The literature and references were reviewed one by one. RESULTS AND CONCLUSION: Stem cell-derived exosomes exert powerful tissue repair, regeneration and protection capabilities similar to those of stem cells. Stem cell-derived exosomes are a new strategy for “cell-free” therapy, because they can avoid immune rejection, tumorigenic risks and other problems during treatment with stem cell transplantation and have better capabilities of binding extracellular matrix. However, the application of stem cell-derived exosomes in peripheral nerve research still needs a lot of basic researches to be accumulated, and the combination with tissue engineering and genetic engineering needs further exploration. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: The characteristics of laminin that can promote the proliferation of stem cells have been widely concerned. OBJECTIVE: To review the interactions between laminin and many different stem cells, and provide reliable theoretical basis for chondrogenic research and application of stem cells. METHODS: Wanfang, CNKI, PubMed and Web of Science databases were searched for articles related to mechanism of laminin, changes in stem cell behaviors, and cartilage regeneration published from January 2010 to October 2019. The retrieval terms were “laminin” and “steam cells” in Chinese and English. Duplicated and poorly related articles were excluded, and finally 57 articles were included for review. RESULTS AND CONCLUSION: (1) The structural characteristics of laminin were summarized. The spatiotemporal changes of laminin during cartilage development and degradation were analyzed. At the same time, the distribution of laminin expression in natural cartilage tissue and tissue engineered cartilage tissue was compared. (2) The effects of laminin on the proliferation of various stem cells, including embryonic stem cells, induced pluripotent stem cells and adult stem cells, were described. (3) The possible hotspots on the combination of laminin and stem cells for cartilage regeneration were proposed, with the attempt of providing theoretical basis for cartilage repair and regeneration in the future. [ABSTRACT FROM AUTHOR]

Objective To investigate the expression changes of miR-302a and Bcl2Ll 1 and to explore the target gene prediction and verification in folate deficiency mouse ES-D3 cell line. Methods Proper number of mouse ES-D3 cells were cultured in folate-deficient culture medium, and were collected at predetermined time points: 0, 24, 48, 72 h (groups A, B, C, D). MiR-302a and Bcl2111 expression changes (BimEL, BimL, BimS) were detected by real-time qPCR andW estern blotting.M ultiple target gene prediction software was used to predict the binding sites between Bcl2111 and miR-302a. The amplification primers were designed and constructed according to the 3 UTR sequence of Bcl2111. The fragment of the Bcl211 1-3 UTR sequence was cloned into the pmiR-RB-REPORT double luciferase reporter vector, and the wild vector was successfully constructed. Similarly, Bcl2111 mutation primers were designed to construct the mutation vector. M戊－302a mimics and/or negative control were co-transfected with Bcl211 13 UTR double reporter wild vector and/or mutant vector, respectively. Therefore, the following four groups were constructed: group 1 (Bcl21113 UTR wild vector and negative control), group 2 ( Bcl21113-UTR wild vector and miR-302a mimics), group 3 ( Bcl211 l3 -UTR mutation vector and negative control), and group 4 ( Bcl21113UTR mutation vector and miR-302a mimics) . Changes on the relative fluorescence value of the hRluc reporter gene were analyzed to further confirm the interaction between miR-302a and Bcl2111 Results The relative miR-302a mRNA expression in the groups A, B, C, and D was 1. 00 土0. 20, 0. 65 土0 . 32, 0. 50 ± 0. 22, 0.43 土。24, respectively. Compared with the group A, miR-302a expression was down-regulated in the group D (P < 0. 05) . The relative Bcl2111 mRNA expression in the groups A, B, C, and D was 1. 00 土0 . 00, 1 . 22 土0. 19, 1 . 82 ± 0. 37, and 3. 49 ±0. 45, respectively. Compared with the group A, Bcl2111 expression was up-regulated in the group D (P < 0. 05) . The relative BimEL expression in the groups A, B, C, and D was O. 86 士0. 02, 0. 87 士0. 03, 0 . 92 士0 . 02, and 1. 10 士0. 06, respectively. Compared with the group A, the BimEL expression was up-regulated in the groups C and D ( both P < 0. 05 ) . The relative BimL expression in the groups A, B, C, and D was O, 0. 09 土0. 02, 0. 16 士0. 04, and 0. 26 ± 0. 03, respectively. Compared with the group A, the BimL expression was up-regulated in the groups B, C and D ( all P < 0. 05) . The relative BimS expression in the groups A, B, C, and D was O, 0, 0. 11 ± 0 . 04, and 0. 18 ± 0. 04, respectively. Compared with the group A, the BimS expression was up-regulated in the groups C and D ( both P <0. 05) Double luciferase report experiment indicated that the luciferase activities in the groups 1, 2, 3, and 4 were 1 . 00 土0 . 07, 0. 64 ± 0. 02, 1 . 00 土0. 03, and 0. 95 ± 0. 06, respectively. Compared with the other groups, the luciferase activity decreased in the group 2 ( all P < 0. 05 ) . Conclusions The expression of miR-302a was down-regulated, while the expression of Bcl2111 RN A and protein levels were up-regulated in folate deficiency mouse ES-D3 cells. Bcl2111 was strongly interacted with miR-302a, and thus it could be considered as the target gene of miR-302a. [ABSTRACT FROM AUTHOR]

BACKGROUND: Autoimmune diseases are a class of diseases that cause a strong immune response to the continuous lack of self-tissue-specific antigens in the thymus. Hypothyroidism and unstable expression of tissue-specific antigens in the thymus can limit the therapeutic effect. The thymus is mainly composed of thymic epithelial cells, but the limited number of mature thymic epithelial cells and thymic epithelial progenitor cells in the thymus has greatly limited related research. OBJECTIVE: To detect the expression of autoimmune regulator (AIRE) when mouse embryonic stem cells were transformed into thymic epithelial progenitor cells. METHODS: A two-step differentiation method was used to induce the differentiation of mouse embryonic stem cells into endoderm and then into thymic epithelial progenitor cells. The cells were collected at 0, 3, and 13 days of induced differentiation. Immunofluorescence, flow cytometry, western blot and real-time PCR were used to detect the expression of cell-associated genes and proteins. RESULTS AND CONCLUSION: Positive expression of OCT4 and SSEA1 was detected by immunofluorescence at 0 day of induction. The double positive expression of SOX17 and FoxA2 was measured by immunofluorescence at 3 days of induction. The positive expression of EpCAM, K5 and K8 were analyzed by flow cytometry at 13 days of induction. During the directional differentiation of mouse embryonic stem cells, real-time PCR indicated that the expression of PAX1, PAX9, FOXN1 and PLET1 showed an increasing trend. The expression of AIRE gene increased significantly at 0, 3, and 13 days of induction. At the same time, the expression of INS2 gene and GAD67 gene also increased. Western blot assay showed that the expression of AIRE protein gradually decreased at 0, 3, and 13 days of induction; however, insulin protein and GAD67 protein were not detected. Overall findings indicate that mouse embryonic stem cells can successfully differentiate into thymic epithelial progenitor cells with highly expressed AIRE gene, which promotes the expression of INS2 and GAD67 genes, and provides an evaluation basis for cell transplantation in the treatment of autoimmune diseases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Exosomes contain DNA fragments, mRNA, miRNA, functional proteins, transcription factors and other substances with biological activities. Their membrane structure also expresses a variety of antigens and antibody molecules, thus producing various biological effects. Recent studies have shown that it has similar therapeutic effects with stem cell transplantation and can be used as a substitute of stem cell transplantation in the treatment of cardiovascular diseases. OBJECTIVE: To summarize the application of exosomes from different stem cells in the treatment of cardiovascular diseases, so as to provide reference and basis for exosomes applied in the treatment of cardiovascular diseases. METHODS: Articles in PubMed database from 2005 to 2019 were searched using the search terms of "exosomes, cardiovascular diseases, embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells." Articles in databases of CNKI and VIP from 2014 to 2019 were retrieved with the search terms of "exosome, cardiovascular disease, embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells." The literature and references were reviewed one by one. RESULTS AND CONCLUSION: Exosomes derived from stem cells are safer and more effective than stem cell transplantation, and have great potential in the prevention and treatment of cardiovascular diseases. However, the research on the function and use of exosomes is still in its infancy. In addition, low exosome content and cumbersome extraction process limit its clinical application. [ABSTRACT FROM AUTHOR]

BACKGROUND: The emergence and development of cardiac tissue engineering provide a new choice for the treatment of cardiovascular diseases, especially for treating myocardial infarction. OBJECTIVE: To review the research progress of two core elements (cells and biological scaffolds) in cardiac tissue engineering, thereby providing reference and basis for the application of cardiac tissue engineering in the treatment of cardiovascular diseases. METHODS: Articles addressing cardiac tissue engineering in PubMed and CNKI databases published from 2010 to 2019 were searched. The search terms were "cardiac tissue engineering, cardiomyocytes differentiation, bone marrow derived stem cells, human embryonic stem cells, induced pluripotent stem cells, menstrual blood stem cells, biological scaffolds' in English and Chinese, respectively. Finally 78 eligible English articles were included. RESULTS AND CONCLUSION: Many kinds of cells (such as chondrocytes, skeletal muscle cells, cardiac fibroblasts, bone marrow derived stem cells, embryonic stem cells, induced pluripotent stem cells and menstrual blood-derived stem cells) and biological scaffolds (hydrogel, decellularized scaffold, cell sheet and cardiac chip) can be applied in cardiac tissue engineering. But there are still many problems to be solved in cardiac tissue engineering, such as suitable cell sources, development of novel scaffold materials, optimization of induced differentiation technology, optimization of implantation time and route. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neuronal regeneration using stem cell differentiation has gained a lot of attentions from researchers. Although embryonic stem cells and induced pluripotent stem cells have good potential for neuronal differentiation, a high risk of tumor development in vivo limits the further study. OBJECTIVE: To establish a stable system for sorting, culture and neuronal differentiation of amniotic fluid stem cells, and to explore the feasibility as seed cells for neuronal regeneration. METHODS: Amniotic fluid sample (10 mL) was obtained at 19-22 weeks of pregnancy under B-ultrasound guidance, and amniotic fluid stem cells were isolated by c-Kit magnetic beads. The markers Oct-4 and Sox2 of amniotic fluid stem cells were identified by immunofluorescence. The expression levels of c-Kit, Oct-4, Sox2 and Nestin in amniotic fluid stem cells after multiple passages were detected by RT-PCR. Then, the cells were cultured by hanging drop for 4 days to observe the embryoid bodies-like structures. Amniotic fluid stem cells were induced to differentiate into neurons using two-stage method. The expression levels of Neuro D and Tuj1 were observed by immunofluorescence. RESULTS AND CONCLUSION: (1) About 1% of amniotic fluid stem cells were positive for c-Kit. (2) (75.0±4.6)% of amniotic fluid stem cells expressed Oct-4 and (86.0±2.8)% of the cells expressed Sox2. (3) The expression levels of c-Kit, Oct-4, Sox2 and Nestin detected by RT-PCR did not change with passage times. (4) Embryoid bodies-like structures formed after hanging drop culture. (5) Immunofluorescence results showed that amniotic fluid stem cells expressed neuronal marker Tuj1, but without the typical morphological features. RT-PCR detected the expression of Tuj1 in different amniotic fluid stem cell specimens as well as in the same sample after several passages. (6) Amniotic fluid stem cells could have the characteristics of neuron-like cells after induction with basic fibroblast growth factor, brain-derived neurotrophic factor, and neurotrophin factor 3 in two stages, and could express neural stem cell marker Neuro D and neuronal marker Tuj1. [ABSTRACT FROM AUTHOR]

BACKGROUND: Brain tissue is the most complex structure of human development. Many human brain diseases are difficult to reproduce in animals, so the establishment of an in vitro model of brain development has a very important research value. In recent years, with the rapid development of the field of stem cells, an artificial tissue culture technology has emerged, that is, through the three-dimensional culture in vitro, stem cells from a single cell are produced into a complex structure resembling whole organs, which is called organoids. OBJECTIVE: To review the research progress of brain organ in recent years from the aspects of the current situation of brain organ culture, pathogenesis, histological characteristics and application in nervous system diseases, and analyze the research defects of brain organ in order to provide reference for the research in related fields. METHODS: CNKI, Wanfang, and PubMed databases were searched by the first author for related studies published from January 1998 to June 2019. The keywords were "organoids, cerebral organoids, embryonic stem cells, induced pluripotent stem cells, neurogenesis, cerebral cortex, development, neurodegenerative disease" in Chinese, and 'organoids, cerebral organoids, embryonic stem cells, induced pluripotent stem cells, neurogenesis, cerebral cortex, development, neurological diseases, self-organization' in English. Finally, 45 eligible artides were included in result analysis. RESULTS AND CONCLUSION: The cerebral organoids can be effectively developed in vitro by using the self-organization of pluripotent stem cells and adding nerve-inducing factors. As a new biological culture technology, cerebral organoids have great research and application value in investigating development of living tissue, the mechanism of disease formation, tissue replacement therapy and drug experiments. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Chinese Society of Animal Science is the property of Chinese Society of Animal Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: In recent years, with the development of stem cell and regeneration technologies, bone tissue engineering has been rapidly developed. Despite there are a variety of seed cells for bone tissue engineering, researchers need to decide which types of stem cells are the best suitable for their specific purposes. To date, there is no ideal treatment for oral bone tissue repair, although a plenty of therapeutic methods have been proposed. Therefore, it will provide a new idea for repairing oral bone defects by fully utilizing the potential of stem cells during bone regeneration. OBJECTIVE: To review the osteogenic potential of stem cells from different sources on oral bone regeneration, thereby providing a basis for selecting seed cells for tissue engineering. METHODS: Databases of CBM, CNKI, PubMed, Elsevier, and Web of Science were retrieved with the keywords of “stem cell, bone repair, alveolar bone regenerate, osteogenesis, bone tissue” in English and Chinese, respectively. After initial screening of titles and abstracts, irrelevant articles were excluded and 81 eligible articles were included in final analysis. RESULTS AND CONCLUSION: Tissue engineering technology provides a new approach to oral bone regeneration, but the choice of stem cells has not been standardized. Many types of stem cells have been used for bone tissue regeneration, but their roles in the body vary due to different origins of stem cells. Therefore, choosing a suitable type of stem cells is important for the repair of specific tissue damage. In this review, we compared the advantages and disadvantages of embryonic stem cells, mesenchymal stem cells and induced pluripotent stem cells in the oral bone regeneration, and attempted to provide a reference for the selection of seed cells for the regeneration and repair of oral bone tissue. [ABSTRACT FROM AUTHOR]

BACKGROUND: Current research indicates that regulation of endogenous neural stem cells or transplantation of exogenous neural stem cells is the latest and most promising method for the treatment of neurological diseases such as dementia. The success of the differentiation of stem cells from other sources into neural stem cells has provided a new way for the source of neural stem cells. Recent studies have shown that cerebrospinal fluid cannot only nourish nerve cells, but also become an effective and suitable inducer to add new ways for the acquisition of neural stem cells. OBJECTIVE: To review the effects of cerebrospinal fluid on stem cells at home and abroad, in order to provide assistance for the clinical application of neural stem cells in the future. METHODS: “Cerebrospinal fluid, stem cells, induced differentiation, neural stem cells, stem cell transplantation therapy” were used as English keywords to search the PubMed database and the Embase database by computer. “Cerebrospinal fluid, stem cells, induced differentiation, proliferation, differentiation, neural stem cells, mesenchymal stem cells, embryonic stem cells, ginkgo biloba extract, stem cell transplantation therapy, neurodegenerative diseases” were used as Chinese keywords to search CNKI database, WanFang database, VIP database and other scientific journal databases. The search time was from December 10th, 1998 to December 10th, 2018. The effects of cerebrospinal fluid on mesenchymal stem cells, embryonic stem cells, and neural stem cells were summarized and analyzed, providing assistance for the clinical use of neural stem cells in the future. RESULTS AND CONCLUSION: (1) Interaction of cerebrospinal fluid and stem cells is the hope of treating nervous system diseases. (2) Cerebrospinal fluid can promote the differentiation of mesenchymal stem cells into neuron-like cells. (3) Cerebrospinal fluid can induce human embryonic stem cells to differentiate into neuron-like cells, but the proportion of different types of cells obtained is different. (4) Cerebrospinal fluid can induce the proliferation and differentiation of endogenous neural stem cells. [ABSTRACT FROM AUTHOR]

Objective To study the role of nicotinamide phosphoribosyltransferase(Nampt)gene in the growth of human embryonic stem cells. Methods CRISPR/Cas9 technology was used for Nampt gene knockout in human embryonic stem cells by introducing frame-shift mutation to gene coding region. Then, the mutational cells were screened with gene sequencing and observed for the growth situation under the microscope. In addition, Nampt inhibitor FK866 was introduced at different concentrations to interfere the growth of human embryonic stem cells, followed by the cell viability test with CCK-8 kit. Results Human embryonic stem cells gradually died after the mutation of Nampt gene with CRISPR/Cas9 technology. Likewise, Nampt inhibitor FK866 significantly inhibited the cell viability and gradually led to the death of cells. Conclusion Nampt gene plays an indispensable role in maintaining the growth of human embryonic stem cells. [ABSTRACT FROM AUTHOR]

Objective: To study the role of Lefty1 in the process of mouse embryonic stem cell differentiation. Methods: According to the chromatin immunoprecipitation sequencing results, there are four binding regions of Smad2/3 protein near above and 10 kb upstream from Lefty1 transcription starting site. To achieve knock out cell lines of four different regions by the CRISPR/Cas9 system, the transcription level of Lefty1 was detected by using real-time quantitative PCR. The knockout cells were treated with the TGF-β activator AC and inhibitor SB, to detect TGF-β signal response. Then, the expression level of mesendoderm markers Gsc and Mixl1 was detected during embryoid body formation in knockout cell lines. Results: The different four regions were knocked out by the CRISPR/Cas9 system. Compared with the wild type, the transcription level of Lefty1 RNA in knockout cell lines was significantly decreased, and the TGF-β signal response of knockout cell lines was lower in ES state and EB state. Compared with the wild type, the basal level of Lefty1 expression in the knockout cell lines was significantly reduced, and the transcription level of mesendoderm markers Gsc and Mixl1 was also decreased significantly during embryoid body formation. Conclusions: The regions near above and 10 kb upstream from Lefty1 transcription start site regulate the transcription process of Lefty1 through the TGF-β pathway-dependent manner, which further regulates the expression of mesendoderm markers Gsc and Mixl1. [ABSTRACT FROM AUTHOR]

BACKGROUND: With the in-depth research on stem cell repair and regeneration, stem cells have been accepted and become an issue of concern in the field of ophthalmology. OBJECTIVE: To review the animal and clinical research advances in the application of stem cells for the treatment of ophthalmic diseases. METHODS: The PubMed and CNKI databases were searched by the first author using the keywords of "stem cell, embryonic stem cell, ophthalmic diseases, limbal stem cell, adult stem cell" in English and Chinese, respectively. The retrieval time was from 1990 to 2017. After removal of repetitive or unrelated articles, 44 eligible articles were included in final analysis. RESULTS AND CONCLUSION: Stem cells are a specific cell group with self-renewing ability and multidirectional differentiation potential. It can be involved in the repair and reconstruction of damaged tissues. For the patients with serious injury or necrosis of the eye tissue and cells, stem cells as the core of regenerative medicine are used to repair the damaged eye tissue and cells and help to reconstruct visual functions. In China, the current research on stem cells in the field of ophthalmology is still in preclinical research stage. Considering the relevant data, we can conclude that stem cells have broad prospects in the treatment of ophthalmic diseases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Y-27632 is a Rho-associated coil-formed protein kinase inhibitor that can regulate the self-renewal of stem cells, promote clonal formation and cell survival, and regulate and protect neuronal cell growth and development. How to improve the differentiation efficiency of embryonic stem cells into neuron-like cells is highly important for nerve injury repair and nerve regeneration. OBJECTIVE: To investigate the effect of Y-27632 on the differentiation efficiency and function of human embryonic stem cells into neuron-like cells. METHODS: After resuscitation, human embryonic stem cells at passage 16 were subjected to morphological observation and staining identification. The embryoid bodies were prepared by suspension culture, and after 8 days of incubation, the cells were cultured in Sato medium containing different concentrations of Y-27632 (0, 5, 10, 20, 40 μmol/L) for 10 days and identification by staining. After induction for 18 days, the differentiation efficiency and neurite outgrowth were identified by immunofluorescence staining. RESULTS AND CONCLUSION: The human embryonic stem cells co-expressed Oct4 and SSEA-3 stem cell specific markers. After suspension culture for 8 days and further adherent culture for 10 days, the cells could be differentiated into neuron-like cells with neurogenic morphology and expressing Tuj-1. Y-27632, especially at a concentration of 10 μmol/L, not only promoted cell proliferation (a significant increase in adherent cells an Tuj-1 positive cells), but also facilitated cell differentiation into neurons. Immunofluorescence staining findings showed that 10 μmol/L Y-27632 significantly increased the number of Tuj-1 positive cells and neurites and the length of neurites after 18 days of differentiation. These results indicate that Y-27632 not only promotes the differentiation of human embryonic stem cells into neuron-like cells, but also accelerates neurite outgrowth. [ABSTRACT FROM AUTHOR]

BACKGROUND: In traditional culture systems for embryonic stem cells, feeder cell preparation and embryonic stem cell culture are mostly performed under normoxic conditions. Changes in oxygen culture conditions are likely to influence feeder cells, thereby altering the growth characteristics or differentiation ability of embryonic stem cells, but there is still no relevant systematic report until now. OBJECTIVE: To investigate the effects of sustained hypoxia culture on the pluripotency of mouse embryonic stem cells cultured on mouse embryonic fibroblast feeder layers. METHODS: Primary mouse embryonic fibroblasts were persistently subcultured under normoxia (20% O2) and hypoxia (5% O2) conditions. Cell proliferation was measured for drawing growth curve. Reactive oxygen species level and mitochondria membrane potential of the feeder cells were detected respectively. Mouse embryonic stem cells were divided into two groups: normoxia group (plated on mouse embryonic fibroblast feeder layers under 20% O2), and hypoxia group (plated on mouse embryonic fibroblast feeder layers under 5% O2). The cell morphology was observed and the pluripotency of embryonic stem cells were detected by measurement of Oct4 and Sox2 expressions. Hypoxia inducible factor-1α mRNA expression was also tested in the four groups. RESULTS AND CONCLUSION: As compared to the normoxia group, mouse embryonic fibroblasts in the hypoxia group proliferated faster, reactive oxygen species significantly declined, and the mitochondria membrane potential level increased significantly (P < 0.05). Embryonic stem cells were positive for alkaline phosphatase, and highly expressed Oct4 and Sox2 mRNA. Much more median- or small-sized colonies formed in the hypoxia group than the normoxia group (P < 0.05). The mRNA expression of hypoxia inducible factor-1α in embryonic stem cells had a significant difference between the hypoxia and normoxia groups (P < 0.05). These findings indicate that a sustained hypoxia environment can significantly promote the viability of mouse embryonic fibroblasts as feeder layers and maintain the pluripotency of embryonic stem cells under 5% O2. [ABSTRACT FROM AUTHOR]

BACKGROUND: Stem cells are the potentially immortal cells capable of self-renewal, which are essential to the mystery of human development and aging, and are also the core of research for regenerative medicine. OBJECTIVE: To summarize the biological characteristics of embryonic stem cells, adult stem cells and induced pluripotent stem cells, to review the clinical and commercial applications in stem cell therapy and drug screening, and to analyze the problems and prospects in stem cell industry. METHODS: We searched relevant articles about stem cell models in PubMed and CNKI databases during 1995 to 2017 on internet, and took "stem cells, embryonic stem cells, adult stem cells, induced pluripotent stem cells, stem cell therapy, drug screening" as the keywords in English and Chinese, respectively. RESULTS AND CONCLUSION: According to the origin, stem cell models are divided into three types: embryonic stem cells, adult stem cells and induced pluripotent stem cells. Different types of stem cells have their unique biological advantages. Embryonic stem cells can generate all somatic cell types, but the application is limited by ethical disputes. As for adult stem cells, there are the most extensive and in-depth, studies as the well as the most prevalent and mature applications. Induced pluripotent stem cells have similar characteristics as embryonic stem cells, and furthermore their use avoids source restriction, moral and ethical controversies, bringing new opportunities for stem cell application. Stem cell-based cell therapy has shown successful achievement. There have been a few commercial products about adult stem cells-based cell therapy; in the meanwhile both embryonic stem cells and induced pluripotent stem cells are making their way into clinical trials. In addition, pluripotent stem cells hold great promise for the specific drug screening because they enable scientists to establish a variety of cell and disease models in vitro. [ABSTRACT FROM AUTHOR]

Objective To investigate the regulatory role of forkhead box O1 (FoxO1) on differentiation of human embryonic stem cells (hESCs) into insulin producing cells (IPCs). Methods The expression levels of FoxO1 during IPC differentiation of hESCs in vitro were determined by realtime PCR and Western blotting. The dynamic expression of octamer-binding transcription factor 4 (Oct4), forkhead box a2 (Foxa2), pancreatic and duodenal homeobox 1 (Pdx1) and insulin during the differentiation was analyzed by realtime PCR. The stage-3 cells (pancreatic progenitors) of the differentiation were infected with FoxO1-knockdown and FoxO1-overexprssion lentiviral vectors. The expression levels of Foxa2, Pdx1 and insulin were detected by realtime PCR. The infected cells were induced to differentiate into IPCs, and glucose stimulated insulin secretion was measured by using an ELISA kit. t test was used to compare the difference between two groups, and one-way ANOVA was used among the groups. Results FoxO1 mRNA and protein were invariably expressed during the differentiation of hESCs to IPCs. The expression level of Oct4 dropped significantly with the differentiation progress. The expression level of Foxa2 increased during the differentiation and peaked at stage 3 of the differentiation. The expression levels of Pdx1 and insulin were significantly upregulated during the differentiation. In the infected pancreatic progenitors, the mRNA levels of Foxa2 (4.31±0.74 vs 1.00±0.34, t=7.08, P<0.01), Pdx1 (2.91±0.24 vs 1.00±0.15, t=11.62, P<0.01) and insulin in the FoxO1-knockdown group were significantly increased compared with those in its control group. By contrast, overexpression of FoxO1 downregulated the mRNA level of insulin (0.81±0.07 vs 1.00± 0.03, t=4.19, P<0.05), but had no effect on the mRNA levels of Foxa2 and Pdx1. In addition, knockdown of FoxO1 promoted insulin secretion stimulated by both low glucose (2 mmol/L) (7.53±2.02 vs 1.00±0.05, t= 3.23, P<0.05) and high glucose (20 mmol/L) (17.39±3.04 vs 6.45±1.34, t=3.30, P<0.05). Overexpression of FoxO1 had little effect on insulin secretion under low glucose, but inhibited high glucose stimulated insulin secretion (2.02 ± 0.50 vs 4.85 ± 1.42, t=2.61, P<0.05), thus resulting in loss of responsibility to glucose. Conclusion FoxO1 negatively regulates the IPC differentiation of hESCs. Inhibition of FoxO1 expression may be a potential strategy for promoting the differentiation and maturation of IPCs from hESCs. [ABSTRACT FROM AUTHOR]

BACKGROUND: The in vitro differentiation methods of stem cell-derived dopaminergic neurons that serve as a cell source for the replacement therapy of Parkinson's disease are continuously optimized and improved, as well as the subsequent identification methods and testing indicators. OBJECTIVE: To observe the morphological development and electrophysiological characteristics of dopaminergic neurons differentiated from human embryonic stem cells so as to identify whether these differentiated cells have mature morphology and function under the current differentiation program. METHODS: Monolayer adherent method combined with dual-SMAD signaling inhibition was used to induce the directional differentiation of human embryonic stem cells into dopaminergic neurons. Then the cells were identified by light microscopy, electron microscopy and immunofluorescence, and the electrophysiological properties of dopaminergic neurons were detected by patch clamp electrophysiological technique. Herein, we evaluated the electrophysiological functions of dopaminergic neurons differentiated in vitro, with reference to the evaluation standard of dopaminergic neuron in vivo. RESULTS AND CONCLUSION: In this study, we successfully obtained dopaminergic neurons with mature morphology and functions differentiated from human embryonic stem cells in vitro. Findings from the subsequent electrophysiological test confirmed that dopaminergic neurons we acquired had electrophysiological properties in accordance with the evaluation standards of dopaminergic neurons in vivo. To conclude, the monolayer adherent method combined with dual-SMAD signaling inhibition can successfully induce the directional differentiation of human embryonic stem cells into dopaminergic neurons with mature morphology and functions. [ABSTRACT FROM AUTHOR]

BACKGROUND: Raman spectrum, compared with conventional detection technologies, is a rapid, non-invasive and label-free optical method. Its application has become an issue of concern in biomedical research. However, further studies are warranted to optimize the acquisition condition of Raman spectra from different stem cells. OBJECTIVE: To explore the effect of the wavelength of laser and the groove frequency of gratings to obtain the optimized parameter combination for Raman spectrum collection in human stem cells. METHODS: Using human mesenchymal stem cells as samples, the effects of different laser wavelengths (532, 638, 785 nm) and different grating groove frequency (600, 1 200, 1 800 gr/mm) on Raman spectra were compared respectively. Then the different combinations of the wavelength and groove frequency were used and compared in terms of the spectra resolution and acquisition time, and the best acquisition condition was selected and applied in a comparison study on the Raman spectra from human mesenchymal stem cells and human embryonic stem cells. RESULTS AND CONCLUSION: The wavelengths of lasers and groove frequencies of gratings showed compound impacts on both the spikes at different wavenumbers and the ratio between spikes; the combination of 785 nm and 1 200 gr/mm was confirmed to be the best spectrum features for human mesenchymal stem cells. The comparison of Raman spectra from human mesenchymal stem cells and human embryonic stem cells implies that the embryonic stem cells contain higher nucleic acids than the mesenchymal stem cells, while the mesenchymal stem cells appear to contain more proteins and lipids. [ABSTRACT FROM AUTHOR]

Stem cells are pluripotent cells with capacity self-replication, such as embryonic stem cells and induced pluripotent stem cells, which can differentiate into a variety of cell types including retinal photoreceptor cells under certain conditions. Small molecule compounds are a kind of small molecule polypeptide, which is synthesized and secreted by the tissue cells and act on stem cells to induce their differentiation into retinal photoreceptor. Stem cells are cultured in vitro, and the study of the differentiation of stem cells into retinal photoreceptor cells has become a hot spot by using different induction culture programs. In order to provide the help for the further study of the differentiation of stem cells into the photoreceptor cells of retina and the clinical treatment of retinal degeneration diseases. In the early stage, researchers mainly used small molecule compounds to induce ESC to differentiate into photoreceptor cells under co culture conditions. With the development of the research, it has been gradually explored that small molecule compounds induce ESC to differentiate into photoreceptor cells in the absence of co culture and the differentiation of iPSC into photoreceptor cells induced by small molecules. In this paper, the research status of small molecular compounds promoting embryonic stem cells and induced pluripotent stem cells to differentiate into retinal photoreceptor cells were reviewed. [ABSTRACT FROM AUTHOR]

The effects of chemicals or drugs on germ cells or early embryos may lead to infertility or the impaired development of pre-implantation embryos. Studies showed that this impaired development could result in embryotoxic or teratogenic effects. The reliable data on the potential toxic effect on human embryos is necessary for any new drug before its clinical application. Embryonic stem cell （ＥＳＣ） is widely used as a cell model in the embryotoxic study due to its unique capacities of self-renewal and differentiation. The embryonic stem cell test （ＥＳＴ） is an in vitro alternative method to evaluate embryotoxicity, which have obtained international recognition. However, EST has its limitations in speedability and sensitivity. The induced pluripotent stem cells （ｉＰＳＣ） with characteristics of proliferation and differentiation, similar to ESC, has gradually been used in the embryonic toxicity test. [ABSTRACT FROM AUTHOR]

Long noncoding RNA (lncRNA) refers to RNA transcripts with more than 200 nucleotides in length, which plays regulatory roles directly in the form of RNA. Their functions are affected by their secondary structures, post transcriptional modification and so on. LncRNA can be classified to various subtypes with complicated mechanisms. In human-induced-pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs), dynamic expression of some lncRNAs is detected during the neuronal differentiation, and a series of lncRNAs associated closely with the development process of the central nervous system (CNS) are found. This review summarizes the molecular biological properties of lncRNA and their regulatory functions in the development of the CNS, which is helpful to reveal the mechanisms of the pathogenesis and progression of certain neurological diseases and results in innovation of their diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Objective To study the effects of Yiqi Huoxue Huatan (qi-replenishing blood-activating phlegm-resolving) Formula on proliferation and differentiation of rat embryonic neural stem cells (NSC). Methods The rat NSC were divided into five groups, including blank serum group, drug serum group, blank serum + LY294002 group, drug serum + LY294002 group, and culture medium control group. The effects of drug serum on cell proliferation and differentiation were evaluated by cell culturing, serum pharmacology, immunofluorescence techniques. Morphological changes were observed by phase contrast microscope. Nestin, neuron-specific enolase (NES) and glial fibrillary acidic protein (GFAP) were measured by using immunofluorescence staining. Results Morphologically, drug serum was non-toxic to neural stem cells and promoted the differentiation of neural stem cells. Immunofluorescence staining showed that nestin expression increased within 24 h yet decreased significantly after 72 h incubation. NES and GFAP positive cells increased significantly in the drug serum group, compared with control group. Conclusion The serum from the rats treated with Yiqi Huoxue Huatan Formula has significant effects on differentiation and proliferationof NSC. [ABSTRACT FROM AUTHOR]

Stem cells have the ability to self renew and proliferate and differentiate, which can be divided into embryonic stem cells(ESC) and adult stem cells(ASC) according to their developmental stages. Stem cells have considerable plasticity in multidisciplinary clinical treatment because of the special potential, which is of great significance. With the discovery of endometrial stem cells and the progress of extraction methods, stem cells have brought new ideas for the treatment of endometrial related diseases. Besides, significant results have been achieved in several fields of research, such as in utero stem cell transplantation for the treatment of fetal diseases, plerosis of injured vascular endothelial cells induced by stem cell, improvement of fertility function and treatment of infertility. This paper gave a review on the resent research of several common diseases in obstetrics and gynecology at home and abroad in the last 7 years. [ABSTRACT FROM AUTHOR]