Retinoic acid induces differentiation of cochlear neural progenitor cells into hair cells / O ácido retinoico induz a diferenciação das células progenitoras neurais cocleares em células ciliadas

Abstract Introduction: Inner ear progenitor cells have the potential for multi-directional differentiation. Retinoic acid is an important requirement for the development of the inner ear. Blocking the Curtyr's retinoic acid signaling pathway can significantly reduce the number of hair cells. Therefore, we believe that retinoic acid may induce the regeneration of inner ear hair cells. Objective: To investigate whether the cochlear neural progenitor cells maintain the characteristics of stem cells during recovery and subculture, whether retinoic acid can induce cochlear neural progenitor cells into hair cells in vitro, and whether retinoic acid promotes or inhibits the proliferation of cochlear neural progenitor cells during differentiation. Methods: Cochlear neural progenitor cells were cultured and induced in DMEM/F12 + RA (10−6M) and then detected the expressions of hair cell markers (Math1 and MyosinVIIa) by immunofluorescence cytochemistry and realtime-polymerase chain reaction, and the proliferation of cochlear neural progenitor cells was detected by Brdu. Results: The nestin of cochlear neural progenitor cells was positively expressed. The ratios of Math1-positive cells in the control group and experimental group were 1.5% and 63%, respectively; the ratios of MyosinVIIa-positive cells in the control group and experimental group were 0.96% and 56%, respectively (p <0.05). The ratios of Brdu+-labeled cells in retinoic acid group, group PBS, and group FBS were 20.6%, 29.9%, and 54.3%, respectively; however, the proliferation rate in the experimental group decreased. Conclusion: Retinoic acid can promote cochlear neural progenitor cells to differentiate into the hair cells.

Resumo Introdução: As células progenitoras da orelha interna têm potencial para diferenciação multidirecional. O ácido retinoico é uma condição importante para o desenvolvimento da orelha interna. O bloqueio da via de sinalização do ácido retinoico no órgão de Corti pode reduzir significativamente o número de células ciliadas. Portanto, acreditamos que o ácido retinoico pode induzir a regeneração das células ciliadas do ouvido interno. Objetivo: Investigar se as células progenitoras neurais cocleares mantêm as características das células-tronco durante a recuperação e subcultura, se o ácido retinoico pode induzir a transformação de células progenitoras neurais cocleares em células ciliadas in vitro e se o ácido retinoico promove ou inibe a proliferação das células progenitoras durante a diferenciação. Método: As células progenitoras neurais cocleares foram cultivadas e induzidas em DMEM/F12+AR (106M) e, então, foram detectadas as expressões de marcadores das células ciliadas (Math1 e Myosin?a) com o uso de citoquímica por imunofluorescência e real time -polymerase chain reaction e a proliferação de células progenitoras neurais cocleares foi detectada pelo teste Brdu. Resultados: A nestina das células progenitoras neurais cocleares foi expressa positivamente. As proporções de células positivas para Math1 no grupo controle e no grupo experimental foram 1,5% e 63%, respectivamente; as proporções de células positivas para Myosin?a no grupo controle e no grupo experimental foram de 0,96% e 56%, respectivamente (p <0,05). As proporções de células marcadas com Brdu+ no grupo ácido retinoico, grupo PBS e grupo FBS foram de 20,6%, 29,9% e 54,3%, respectivamente; no entanto, a taxa de proliferação no grupo experimental diminuiu. Conclusões: O ácido retinoico pode promover a diferenciação das células progenitoras neurais cocleares em células ciliadas.

The COMPASS Core Member Ash2l Regulates the Cell Cycle of Neural Progenitor Cells / 中国生物化学与分子生物学报

To investigate the role of Ash2l (absent, small, or homeotic 2-like, Ash2l) on the proliferation ability and cell cycle of mouse cerebral cortical neural progenitor cells (NPCs), We examined the number and distribution of NPCs, using the radial glial cell marker PAX6 and intermediate progenitor cell marker TBR2. E16. 5 mice were labeled with EdU for 30 min to detect the proliferation ability of NPCs. Conditional knockout of Ash2l resulted in a dramatic reduction in the number of NPCs and a disordered distribution. The 30 min EdU insertion experiment showed that EdU could hardly be inserted into NPCs, indicating that the proliferation ability of NPCs was severely affected. Using the mitotic cell cycle marker pH3, the distribution of dividing NPCs was observed. We then detected the expressed level of Cyclin A by Western blotting. The distribution of cell nuclei of M-phase is disordered and the expression of G

Therapeutic potentials of neural stem cells in Alzheimer’s disease

@#The commonest cause of dementia among the elderly population is Alzheimer’s disease (AD). It is a health concern globally as the number of people affected by dementia worldwide is rapidly increasing. Several genes have been linked to AD and the pathogenesis of the disease has been extensively and vigorously examined. Thus far, only a few drugs have been approved by the Food and Drug Administration (FDA) for the pharmacological treatment of AD and a growing body of research has turned to alternative options such as stem cell therapy. This review will give an overview of the pathological and clinical aspects of AD. Although researchers have explored the suitability and feasibility of using various types of stems cells to treat AD, this review will focus mainly on neural stem cells (NSCs)/ neural progenitor cells (NPCs). The behaviour and properties of NSCs will be described, accompanied by a comprehensive discussion of the therapeutic strategies involving the use of NSCs/NPCs in the treatment of the disease

Restorative Mechanism of Neural Progenitor Cells Overexpressing Arginine Decarboxylase Genes Following Ischemic Injury

Cell replacement therapy using neural progenitor cells (NPCs) following ischemic stroke is a promising potential therapeutic strategy, but lacks efficacy for human central nervous system (CNS) therapeutics. In a previous in vitro study, we reported that the overexpression of human arginine decarboxylase (ADC) genes by a retroviral plasmid vector promoted the neuronal differentiation of mouse NPCs. In the present study, we focused on the cellular mechanism underlying cell proliferation and differentiation following ischemic injury, and the therapeutic feasibility of NPCs overexpressing ADC genes (ADC-NPCs) following ischemic stroke. To mimic cerebral ischemia in vitro , we subjected the NPCs to oxygen-glucose deprivation (OGD). The overexpressing ADC-NPCs were differentiated by neural lineage, which was related to excessive intracellular calcium-mediated cell cycle arrest and phosphorylation in the ERK1/2, CREB, and STAT1 signaling cascade following ischemic injury. Moreover, the ADC-NPCs were able to resist mitochondrial membrane potential collapse in the increasingly excessive intracellular calcium environment. Subsequently, transplanted ADC-NPCs suppressed infarct volume, and promoted neural differentiation, synapse formation, and motor behavior performance in an in vivo tMCAO rat model. The results suggest that ADC-NPCs are potentially useful for cell replacement therapy following ischemic stroke.

Diffuse Intrinsic Pontine Gliomas Exhibit Cell Biological and Molecular Signatures of Fetal Hindbrain-Derived Neural Progenitor Cells / 神经科学通报·英文版

Diffuse intrinsic pontine glioma (DIPG) is the main cause of brain tumor-related death among children. Until now, there is still a lack of effective therapy with prolonged overall survival for this disease. A typical strategy for preclinical cancer research is to find out the molecular differences between tumor tissue and para-tumor normal tissue, in order to identify potential therapeutic targets. Unfortunately, it is impossible to obtain normal tissue for DIPG because of the vital functions of the pons. Here we report the human fetal hindbrain-derived neural progenitor cells (pontine progenitor cells, PPCs) as normal control cells for DIPG. The PPCs not only harbored similar cell biological and molecular signatures as DIPG glioma stem cells, but also had the potential to be immortalized by the DIPG-specific mutation H3K27M in vitro. These findings provide researchers with a candidate normal control and a potential medicine carrier for preclinical research on DIPG.

Role of a 19S Proteasome Subunit- PSMD10(Gankyrin) in Neurogenesis of Human Neural Progenitor Cells

PSMD10(Gankyrin), a proteasome assembly chaperone, is a widely known oncoprotein which aspects many hall mark properties of cancer. However, except proteasome assembly chaperon function its role in normal cell function remains unknown. To address this issue, we induced PSMD10(Gankyrin) overexpression in HEK293 cells and the resultant large-scale changes in gene expression profile were analyzed. We constituted networks from microarray data of these differentially expressed genes and carried out extensive topological analyses. The overrecurring yet consistent theme that appeared throughout analysis using varied network metrics is that all genes and interactions identified as important would be involved in neurogenesis and neuronal development. Intrigued we tested the possibility that PSMD10(Gankyrin) may be strongly associated with cell fate decisions that commit neural stem cells to differentiate into neurons. Overexpression of PSMD10(Gankyrin) in human neural progenitor cells facilitated neuronal differentiation via β-catenin Ngn1 pathway. Here for the first time we provide preliminary and yet compelling experimental evidence for the involvement of a potential oncoprotein – PSMD10(Gankyrin), in neuronal differentiation.

T-Type Calcium Channels Are Required to Maintain Viability of Neural Progenitor Cells

T-type calcium channels are low voltage-activated calcium channels that evoke small and transient calcium currents. Recently, T-type calcium channels have been implicated in neurodevelopmental disorders such as autism spectrum disorder and neural tube defects. However, their function during embryonic development is largely unknown. Here, we investigated the function and expression of T-type calcium channels in embryonic neural progenitor cells (NPCs). First, we compared the expression of T-type calcium channel subtypes (CaV3.1, 3.2, and 3.3) in NPCs and differentiated neural cells (neurons and astrocytes). We detected all subtypes in neurons but not in astrocytes. In NPCs, CaV3.1 was the dominant subtype, whereas CaV3.2 was weakly expressed, and CaV3.3 was not detected. Next, we determined CaV3.1 expression levels in the cortex during early brain development. Expression levels of CaV3.1 in the embryonic period were transiently decreased during the perinatal period and increased at postnatal day 11. We then pharmacologically blocked T-type calcium channels to determine the effects in neuronal cells. The blockade of T-type calcium channels reduced cell viability, and induced apoptotic cell death in NPCs but not in differentiated astrocytes. Furthermore, blocking T-type calcium channels rapidly reduced AKT-phosphorylation (Ser473) and GSK3β-phosphorylation (Ser9). Our results suggest that T-type calcium channels play essential roles in maintaining NPC viability, and T-type calcium channel blockers are toxic to embryonic neural cells, and may potentially be responsible for neurodevelopmental disorders.

Neurotrophin-3 Chitosan Scaffolds Induced Hippocampal Neural Network Formation after Traumatic Brain Injury in Adult Rats / 中国康复理论与实践

@#Objective To repair the traumatic brain injury in adult rats by inducing neural synapses formation with neurotrophin- 3 (NT-3) chitosan scaffolds. Methods 60 adult male Wistar rats were equally divided into lesion group, blank chitosan scaffolds group and NT-3 chitosan scaffolds group. The neural regeneration in the lesion area were observed through immunochemistry 3 days, 7 days, 14 days,28 days, 60 days after operation. Regenerated neural synapses involved the neural circuitry reconstruction in the lesion area were observed through neural tracing and immune electron microscopy 30 days and 60 days after operation. Results The nestin+, β-tubulin-Ⅲ+, microtubule associated protein 2 (MAP2)+ neural cells in hippocampal lesion area were significantly more in the NT-3 chitosan scaffolds group than in the other groups (P<0.01). Newborn neurons that express 5-bromouracil deoxyriboside (BrdU) and MAP2 were observed and formed synaptic connections in hippocampal damage zone in the NT-3 chitosan scaffolds group. Regenerated neural synapses involved the neural circuitry reconstruction in the lesion area. Conclusion NT-3 chitosan scaffolds activate the neural progenitor cells to proliferate and differentiate to mature neurons, which form neural synapses to involve the neural circuitry reconstruction.

Hepatocyte growth factor enhances the neural differentiation from human embryonic stem cells / 中国病理生理杂志

AIM: To investigate the possibility that hepatocyte growth factor (HGF) directly induces differentiation of human embryonic stem cells (hESCs) into neural progenitors (NPs). METHODS: hESCs colonies were induced to form the embryoid body (EB). Four-day-old EBs were randomly divided into 4 groups: control group (EBs were cultured in neural induction medium);G5 supplement group (EBs were cultured in neural induction medium supplied with G5 supplement);HGF group (EBs were cultured in neural induction medium supplied with 10 mg/L HGF), and HGF+G5 group (EBs were cultured in neural induction medium supplied with 10 mg/L HGF and G5 supplement). After induced in suspension system for 7 days, EBs with various treatments were cultured in poly-D-lysine/laminin-coated plates for 7-10 days for selection of NPs. NPs were gathered by 0.3 g/L dispase treatment and characterized by immunofluorescence staining. The percentages of the nestin+ cells in NPs in various groups were detected by fluorescent activated cell sorter (FACS). The multipotency of NPs was determined by immunofluorescence staining after the NPs were cultured without G5 and HGF for 7 days. The expression of region markers of neural progenitors treated with sonic hedgehog (Shh) protein (one of the neural inductive signals), was detected by RT-PCR. RESULTS: HGF+G5 supplement induced hESCs differentiation into neural progenitors. Immunofluorescence staining indicated that NPs differentiated from hESCs expressed NP markers including nestin, Pax6 and musashi-1. FACS data showed that the proportion of nestin positive cells in HGF+G5 supplement group (87.3%±3.9%) was the highest in all treatment groups. The time of HGF and G5 supplement treatment was important to differentiate into NPs, the maximal effect was observed at 7th day. After treated with Shh, the expression of ventral forebrain/hindbrain marker genes (Nkk2.1, and Nkk2.2) and hindbrain progenitor marker gene Gbx2 in NPs were upregulated, while the forebrain progenitor marker genes Otx2 and Bf1 were downregulated. CONCLUSION: The neural induction system containing HGF and G5 supplement effectively induces the differentiation of hESCs into NPs, which might be a potent model for investigating the mechanism of neural development and differentiation.

Efficient Derivation of Mesenchymal Stem Cells and Neural Precursor Cells From Human Embryonic Stem Cells Through Teratoma Formation / 生物化学与生物物理进展

Many somatic cell typos were obtained by in vitro differentiation or teratoma formation of human embryonic stem ceLls (hESCs). However, it is unclear whether specific cell types can be obtained from hESCs-derived teratoma. It was reported that many kinds of cells, including neural progetfitor/precursor cells (NPCs) and mesenchymal stem cells (MSCs) were isolated efficiently from the teratoma of hESCs through in vitro selection. The teratoma-derived NPCs and MSCs showed specific characteristics of molecular markers similar to the primary NPCs and MSCs. Moreover, these teratoma-induced NPCs and MSCs can be further induced to differentiate into neurons, astrocytes, or adipose and bone cells, reflecting their inherent multi-potencies. Given that teratoma normally contains a mixture of ectoderm, mesodenn, and endoderm lineage cells at different differentiation stage, it was suggested that hESCs-derived teratoma could be an alternative source to generate a variety of uncommitted progenitor cells or terminally differentiated somatic cells, which may be otherwise difficult to obtain through direct in vitro differentiation.

EFFECTS OF CEREBRAL CORTICAL CONCIS ON CELL PROLIFERATION OF THE SUBVENTRICULAR ZONE IN ADULT RATS / 药物分析学报

Objective To investigate the proliferative response and time course of endogenous neural stem/progenitor cells after cerebral cortical concis in the adult rats. Methods Eighty adult male Sprague-Dawley rats were used in this study. Cumulative BrdU labeling was employed to detect the proliferating cells. At 1 d, 3 d, 7 d, 14 d, and 21 d after cerebral cortical concis, the rats were killed for BrdU immunohistochemical staining and cell counting in the injured ipsilateral SVZ. Results Little BrdU immunoreactivity cells was present in SVZ of the control rats from day 7 to day 21 after sham operation. The number of BrdU immunoreactivity cells in the injured ipsilateral SVZ increased at day 1 and peaked at day 7 after cerebral cortical concis. Conclusion After cerebral cortical concis of the adult rats, neural stem/progenitor cells in the injured ipsilateral SVZ markedly proliferated with a peak at day 7. This finding may be important for manipulating SVZ cells to promote the recovery from cerebral cortical concis.

MR diffusion tensor imaging in the evaluation of neural progenitor cells transplantation to acute injured canine spinal cord / 中华放射学杂志

Objective To observe the effect of transplantation of telomerase immortalized human neural progenitor cells to acute injured canine spinal cord by using MR diffusion tensor imaging (DTI).Methods Telomerase immortalized human neural progenitor cells with expression of green fluorescent protein were prepared for transplantation. Eight adult canines with left spinal cord hemisection at the level of T13 were examined by MR diffusion tensor imaging four times sequentially: prior to injury, one week after injury, one week after transplantation (two weeks after injury), and four weeks after transplantation. Results The ADC values of the injured spinal cord were (1.00?0.15)?10 -3 mm2/s, (1.65?0.45)?10 -3 mm2/s, (1.44?0.48)?10 -3 mm2/s, and (1.43?0.26) ?10 -3 mm2/s, respectively. There was statistically significant difference between the data obtained at different times (F=6.038, P=0.005). The FA values of the injured spinal cord were 0.59?0.11, 0.30?0.17, 0.36?0.25, and 0.34?0.11, respectively. There was also statistically significant difference between the data obtained at different times ( F=5.221,P=0.009). The ADC values of the intact spinal cord were (1.01?0.17)?10 -3 mm2/s, (1.32?0.06)?10 -3 mm2/s, (1.10?0.24)?10 -3 mm2/s, and (1.14?0.22) ?10 -3 mm2/s, respectively. There was no statistically significant difference between the data obtained at different times ( F=1.303,P=0.306). The FA values of the intact spinal cord were 0.60?0.09, 0.38?0.25, 0.46?0.15, and 0.50?0.21, respectively. There was also no statistically significant difference between the data obtained at different times (F=2.797,P=0.072).Conclusion DTI can provide useful information for spinal cord injury and regeneration in experimental spinal cord injury.