How mesenchymal stem cells transform into adipocytes:Overview of the current understanding of adipogenic differentiation

Mesenchymal stem cells(MSCs)are stem/progenitor cells capable of self-renewal and differentiation into osteoblasts,chondrocytes and adipocytes.The transformation of multipotent MSCs to adipocytes mainly involves two subsequent steps from MSCs to preadipocytes and further preadipocytes into adipocytes,in which the process MSCs are precisely controlled to commit to the adipogenic lineage and then mature into adipocytes.Previous studies have shown that the master transcription factors C/enhancer-binding protein alpha and peroxisome proliferation activator receptor gamma play vital roles in adipogenesis.However,the mechanism underlying the adipogenic differentiation of MSCs is not fully understood.Here,the current knowledge of adipogenic differentiation in MSCs is reviewed,focusing on signaling pathways,noncoding RNAs and epigenetic effects on DNA methylation and acetylation during MSC differentiation.Finally,the relationship between maladipogenic differentiation and diseases is briefly discussed.We hope that this review can broaden and deepen our understanding of how MSCs turn into adipocytes.

Comprehensive regulation of traditional Chinese medicine on proliferation and differentiation of neural stem cells

Since the diccovery of neural stem cells(NSCs)in the embryonic and adult mammalian central nerous system,it provided novel ideas forneurogenesis as the potential of proliferation and differentiation of NSCs.One of the ways to promote the clinical application of neural stem cells(NSCs)is searching effective methods which regulate the proliferation and differentiation.This is also a problem urgently to be solved in medical field.Plenty of earlier studies have shown that traditional chinese medicine can promote the proliferation and differentiation of NSCs by regulating the related signaling pathway in vivo and in vitro.The reports of Chinese and foreign literatures on regulating the proliferation and differentiation of neural stem cells in recent ten years and their target and signaling pathways is analyzed in this review.The traditional chinese medicine regulate proliferation and differentiation of NSCs by the signaling pathways of Notch,PI3K/Akt,Wnt/β-catenin,and GFs.And,those signaling pathways have cross-talk in the regulation progress.Moreover,some traditional Chinese medicine,such as astragalus,has a variety of active ingredients to regulate proliferation and differentiation of NSCs through different signaling pathways.However,to accelerate the clinical application of neural stem cells,the studies aboutthe proliferation and differentiation of NSCs and Chinese medicine should be further deepened,the mechanism of multiple targets and the comprehensive regulation function of traditional Chinese medicine should be clarified.

Fetal bovine serum versus Chinese herbal formula Naoluoxintong serum supplementation for proliferation and differentiation of rat embryonic neural stem cells

BACKGROUND： How to induce endogenous neural stem cells （NSCs） to differentiate into needed neural cell types is a hot spot of current researches. OBJECTIVE： To compare differences between fetal bovine serum and Chinese herbal formula Naoluoxintong serum supplementation for inducing proliferation and differentiation in rat embryonic NSCs. DESIGN, TIME AND SETTING： An in vitro, serum pharmacology, comparative, observation study was performed from March to September in 2008 at the Laboratory of Neurodegenerative Diseases, College of Life Science in University of Science and Technology of China, the Key Laboratory Breeding Base of Acupuncture Foundation and Technology in Anhui University of Traditional Chinese Medicine, the Anhui Province Key Laboratory of R ＆ D of Chinese Medicine, and at the Level 3 Laboratory of Molecular Biology of the State Administration of Traditional Chinese Medicine. MATERIALS： The Chinese herbal formula Naoluoxintong was produced by Radix Astragali, Radix Notoginseng, Rhizoma Chuanxiong, Scolopendra at Anhui University of Traditional Chinese Medicine. Mouse anti-rat nestin, gliat fibrillary acidic protein, and galactocerebroside monoclonal antibodies, as well as rabbit anti-neuron-specific enolase polyclonal antibody were produced by Chemicon, Billerica, MA, USA. METHODS： Wistar rats aged 3 months were intragastrically infused with Naoluoxintong. Wistar rat embryonic NSCs （passage 8） were induced to proliferate and differentiate using 10% fetal bovine serum, 10% Naoluoxintong serum, and 10% rat serum. MAIN OUTCOME MEASURES： Phenotypic changes in cultured cells were detected using phase contrast microscopy, and cell proliferation and differentiation were observed using immunofluorescence staining. RESULTS： Proliferation and differentiation of embryonic NSCs was induced by three different types of blood serum. Although the differentiation time course with Nao/uoxintongserum was later than with the other two methods, the differentiated cells were morphologically similar to mature neurons to a greater extent. CONCLUSION： Nao/uoxintong serum supplementation induced differentiation of NSCs into neuronal-like cells and stimulated neuronal maturation.

Propofol and remifentanil at moderate and high concentrations affect proliferation and differentiation of neural stem/progenitor cells

Propofol and remifentanil alter intracellular Ca^2＋ concentration （[Ca^2＋]i） in neural stem/progen-itor cells by activating γ-aminobutyric acid type A receptors and by reducing testosterone levels. However, whether this process affects neural stem/progenitor cell proliferation and differenti-ation remains unknown. In the present study, we applied propofol and remifentanil, alone or in combination, at low, moderate or high concentrations （1, 2–2.5 and 4–5 times the clinically effective blood drug concentration）, to neural stem/progenitor cells from the hippocampi of newborn rat pups. Low concentrations of propofol, remifentanil or both had no noticeable effect on cell proliferation or differentiation; however, moderate and high concentrations of propofol and/or remifentanil markedly suppressed neural stem/progenitor cell proliferation and differen-tiation, and induced a decrease in [Ca^2＋]i during the initial stage of neural stem/progenitor cell differentiation. We therefore propose that propofol and remifentanil interfere with the prolifer-ation and differentiation of neural stem/progenitor cells by altering [Ca^2＋]i. Our ifndings suggest that propofol and/or remifentanil should be used with caution in pediatric anesthesia.

Decreased proliferation ability and differentiation potential of mesenchymal stem cells of osteoporosis rat

Objective:To explore decreased proliferation ability and differentiation potential of mesenchymal stem cells(MSCs) of osteoporosis rat.Methods:MSCs were obtained from osteoporosis rat,and proliferation potency and impaired osteogenic differentiation potential were determined.Results:The result showed a significant downregulation of MSCs pluripotency related gene(Oct4) and osteogenic genes(BSP,OCN) expression in OVX MSCs compared with Sham MSCs(P<0.05).Conclusions:These data suggest that MSCs are aging in osteoporosis body,and autologous OVX MSCs transplantation is not appropriate to treat osteoporosis if necessary.There will be a possibility in establishing a new clinical application of MSCs autologous transplantation to treat osteoporosis,if OVX MSCs have stronger proliferation and differentiation.

Dorsal root ganglion neurons promote proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells

Preliminary animal experiments have confirmed that sensory nerve fibers promote osteoblast differentiation, but motor nerve fibers have no promotion effect. Whether sensory neurons pro- mote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells remains unclear. No results at the cellular level have been reported. In this study, dorsal root ganglion neurons （sensory neurons） from Sprague-Dawley fetal rats were co-cultured with bone marrow mesenchymal stem cells transfected with green fluorescent protein 3 weeks after osteo- genic differentiation in vitro, while osteoblasts derived from bone marrow mesenchymal stem cells served as the control group. The rat dorsal root ganglion neurons promoted the prolifera- tion of bone marrow mesenchymal stem cell-derived osteoblasts at B and 5 days of co-culture, as observed by fluorescence microscopy. The levels of mRNAs for osteogenic differentiation-re- lated factors （including alkaline phosphatase, osteocalcin, osteopontin and bone morphogenetic protein 2） in the co-culture group were higher than those in the control group, as detected by real-time quantitative PCR. Our findings indicate that dorsal root ganglion neurons promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells, which pro- vides a theoretical basis for in vitro experiments aimed at constructing tissue-engineered bone.

PROLIFERATION AND DIFFERENTIATION OF NEURAL STEMCELLS IN ADULT RATS AFTER CEREBRAL INFARCTION

Objective To investigate proliferation and differentiation of neural stem cells in adult rats after cerebral infarction. Methods Models of cerebral infarction in rats were made and the time-course expression of bromodeoxyuridine(BrdU), Musashi1, glial fibrillary acidic protein (GFAP), and neuronal nuclear antigen (NeuN) were determined by immunohistochemistry and immunofluorescence staining. BrdU and Musashi1 were used to mark dividing neural stem cells. GFAP and NeuN were used to mark differentiating neural stem cells. Results Compared with controls, the number of BrdU-labeled and BrdU-labeled with Musashi1-positive cells incre-ased strikingly 1 day after cerebral infarction; approximately 6 fold with a peak 7 days later; markedly decreased 14 days later, but was still elevated compared with that of controls; decling to the control level 28 days later. The number of BrdU-labeled with GFAP-positive cells nearly remained unchanged in the hippocampus after cerebral infarction. The nu-mber of BrdU-labeled with NeuN-positive cells increased strikingly 14 days after cerebral infarction, reached maximum peak in the hippocampus 28 days after cerebral infarction in rats. Conclusion Cerebral infarction stimulate proliferation of inherent neural stem cells and most proliferated neural stem cells differentiate into neurons.

Effects of Aging on the Proliferation and Differentiation Capacity of Human Periodontal Ligament Stem Cells

periodontal ligament stem cells; aging; proliferation; osteogenic differentiation Objective The aim of this study is to investigate the proliferation, differentiation and apoptosis of periodontal ligament stem cells （PDLSC） derived from different aged donors, and to evaluate the effects of aging on the biological characteristics of PDLSC. Methods Periodontal ligament tissues were obtained from 24 surgically extracted human premolars during orthodontics therapy. The specimens were divided into three groups according to the donor’s age. Group A： 18-20 years, group B： 30-35 years, group C： 45-50 years. PDLSC were isolated and cultured using a tissue-block-based enzymolytic method by limiting dilution assay. The colony forming efficiency of PDLSC for three experimental groups was determined. Senescence-Associated β-Galactosidase （SA-β-G） expression in the three groups was examined using β-galactosidase staining working solution. Cell cycle and apoptosis of the PDLSC were examined by the flow cytometry. Alkaline phosphatase （ALP） activity was evaluated by ALP staining. The expression of osteoplastic differentiation related genes Runt-related transcription factor-2 （Runx-2）, Collagen Type 1 （col-1）, and ALP of PDLSC were examined by quantitative real-time RT-PCR. Results The colony forming efficiency of PDLSC in Group A, B and C was 36.67%, 22.67% and 9.33%, respectively, which decreased with donors’ age （P〈0.05）. SA-β-G expression of the senescent PDLSC in group A, B and C were 4.14%, 16.39%, 50.38%, respectively （P〈0.05）. Cells in G2/S phase was 38.73%, 29.88%, 18.25% （P〈0.05）, and the apoptosis rate was 1.57%, 4.56%, 5.84% （P〈0.05）, in group A, B and C respectively. The ALP staining in the three groups decreased with the increase of donors’ ages, and the expression of Runx-2, col-1 and ALP decreased gradually from group A to group C （all P〈0.05）, which indicated the osteogenic differentiation capacity of PDLSC decreased while donor aging. Conclusion Human PDLSC could be successfully isolated from periodontal ligament tissues of different aged donors. However, the proliferation and osteogenic differentiation capacity of PDLSC decreased while donor aging.

Effect of Stathmin Decoy-oligodeoxynucleotides on the Proliferation and Differentiation of Precartilainous Stem Cells

By using decoy-oligodeoxynucleotides （decoy-ODNS） technique, the effects of Stathmin gene on the proliferation and differentiation of in vitro cultured precartilainous stem cells （PSCs） were investigated. The Stathmin decoy-ODNs were transfected into PSCs in rats by using gene transfection technique. Under the induction of cortisol （1 μmol/L）, electrophoretic mobility shift assay was used the inhibitory effects of decoy-ODNS on Stathmin gene. MTT and cytometry were used to test the cell proliferation. The expression of collagen Ⅱ and Ⅴ and Stathmin protein was detected by using Western blot. The results showed that Stathmin decoy-ODNs inhibited the Stathmin activity in a dose-dependent manner. When the concentration of decoy-ODNs was 10 times of standard con- centration, the proliferation of PSCs was obviously suppressed and the differentiation happened. Compared to the control group, the difference was significant （P〈0.05）. It was concluded that decoy-ODNs could inhibit the proliferation and promote the differentiation of PSCs by antagonizing Stathmin activity.

Cerebral dopamine neurotrophic factor promotes the proliferation and differentiation of neural stem cells in hypoxic environments

Previous research found that cerebral dopamine neurotrophic factor(CDNF)has a protective effect on brain dopaminergic neurons,and CDNF is regarded as a promising therapeutic agent for neurodegenerative diseases.However,the effects of CDNF on the proliferation,differentiation,and apoptosis of neural stem cells(NSCs),which are very sensitive to hypoxic environments,remain unknown.In this study,NSCs were extracted from the hippocampi of fetal rats and cultured with different concentrations of CDNF.The results showed that 200 nM CDNF was the optimal concentration for significantly increasing the viability of NSCs under non-hypoxic environmental conditions.Then,the cells were cultured with 200 nM CDNF under the hypoxic conditions of 90%N_2,5%CO_2,and 5%air for 6 hours.The results showed that CDNF significantly improved the viability of hypoxic NSCs and reduced apoptosis among hypoxic NSCs.The detection of markers showed that CDNF increased the differentiation of hypoxic NSCs into neurons and astrocytes.CDNF also reduced the expression level of Lin28 protein and increased the expression of Let-7 mRNA in NSCs,under hypoxic conditions.In conclusion,we determined that CDNF was able to reverse the adverse proliferation,differentiation,and apoptosis effects that normally affect NSCs in a hypoxic environment.Furthermore,the Lin28/Let-7 pathway may be involved in this regulated function of CDNF.The present study was approved by the Laboratory Animal Centre of Southeast University,China(approval No.20180924006)on September 24,2018.

Effects of olfactory ensheathing cells on the proliferation and differentiation of neural stem cells

BACKGROUND： Olfactory ensheathing cells can promote oriented differentiation and proliferation of neural stem cells by cell-secreted neural factors. OBJECTIVE： To observe the effect of olfactory ensheathing cells on the differentiation and proliferation of neural stem cells. DESIGN, TIME AND SETTING： Cytology was performed at the Department of Neurology, Tongji Medical College, Huazhong University of Science and Technology, China, from September 2007 to October 2008. MATERIALS： Mouse anti-nestin polyclonal antibody （Chemicon, USA）, mouse anti-glial fibrillary acidic protein （GFAP） IgG1, mouse anti-2＇, 3＇-cyclic nucleotide 3＇-phosphodiesterase （CNPase） IgG1, mouse anti-Tubulin Class-Ill IgG1 （Neo Markers, USA）, Avidin-labeled Cy3 （KPL, USA）, and goat anti-mouse IgGl： fluorescein isothiocyanate （FITC） （Serotec, UK） were used in this study. METHODS：Tissues were isolated from the embryonic olfactory bulb and subependymal region of Wistar rats. Serum-free DMEM/F12 culture media was used for co-culture experiments. Neural stem cells were incubated in serum-free or 5% fetal bovine serum-containing DMEM/F12 as controls. MAIN OUTCOME MEASURES： After 7 days of co-culture, neural stem cells and olfactory ensheathing cells underwent immunofluorescent staining for nestin, tubulin, glial fibrillary acidic protein, and CNPase. RESULTS： Olfactory ensheathing cells promoted proliferation and differentiation of neural stem cells into neuron-like cells, astrocytes and oligodendrocytes. The proportion of neuron-like cells was 78.2%, but the proportion of neurons in 5% fetal bovine serum DMEM/F12 was 48.3%. In the serum-free DMEM/F12, neural stem cells contracted, unevenly adhered to the glassware wall, or underwent apoptosis at 7 days. CONCLUSION： Olfactory ensheathing cells promote differentiation of neural stem cells mainly into neuron-like cells, and accelerate proliferation of neural stem cells. The outcome is better compared with serum-free medium or medium containing 5% fetal bovine serum.

Ipsilateral versus bilateral limb-training in promoting the proliferation and differentiation of endogenous neural stem cells following cerebral infarction in rats

We investigated the effects of ipsilateral versus bilateral limb-training on promotion of endogenous neural stem cells in the peripheral infarct zone and the corresponding cerebral region in the unaffected hemisphere of rats with cerebral infarction. Middle cerebral artery occlusion was induced in Wistar rats. The rat forelimb on the unaffected side was either wrapped up with tape to force the use of the paretic forelimb in rats or not braked to allow bilateral forelimbs to participate in training. Daily training consisted of mesh drum training, balance beam training, and stick rolling training for a total of 40 minutes, once per day. Control rats received no training. At 14 days after functional training, rats receiving bilateral limb-training exhibited milder neurological impairment than that in the ipsilateral limb-training group or the control group. The number of nestin/glial fibrillary acidic protein-positive and nestin/microtubule-associated protein 2-positive cells in the peripheral infarct zone and in the corresponding cerebral region in the unaffected hemisphere was significantly higher in rats receiving bilateral limb-training than in rats receiving ipsilateral limb-training. These data suggest that bilateral limb-training can promote the proliferation and differentiation of endogenous neural stem cells in the bilateral hemispheres after cerebral infarction and accelerate the recovery of neurologic function. In addition, bilateral limb-training produces better therapeutic effects than ipsilateral limb-training.

Proliferation and tenogenic differentiation of bone marrow mesenchymal stem cells in a porous collagen sponge scaffold

BACKGROUND Collagen is one of the most commonly used natural biomaterials for tendon tissue engineering.One of the possible practical ways to further enhance tendon repair is to combine a porous collagen sponge scaffold with a suitable growth factor or cytokine that has an inherent ability to promote the recruitment,proliferation,and tenogenic differentiation of cells.However,there is an incomplete understanding of which growth factors are sufficient and optimal for the tenogenic differentiation of rat bone marrow mesenchymal stem cells(BMSCs)in a collagen sponge-based 3D culture system.AIM To identify one or more ideal growth factors that benefit the proliferation and tenogenic differentiation of rat BMSCs in a porous collagen sponge scaffold.METHODS We constructed a 3D culture system based on a type I collagen sponge scaffold.The surface topography of the collagen sponge scaffold was observed by scanning electron microscopy.Primary BMSCs were isolated from Sprague-Dawley rats.Cell survival on the surfaces of the scaffolds with different growth factors was assessed by live/dead assay and CCK-8 assay.The mRNA and protein expression levels were confirmed by quantitative real-time polymerase chain reaction and Western blot,respectively.The deposited collagen was assessed by Sirius Red staining.RESULTS Transforming growth factorβ1(TGF-β1)showed great promise in the tenogenic differentiation of BMSCs compared to growth differentiation factor 7(GDF-7)and insulin-like growth factor 1(IGF-1)in both the 2D and 3D cultures,and the 3D culture enhanced the differentiation of BMSCs into tenocytes well beyond the level of induction in the 2D culture after TGF-β1 treatment.In the 2D culture,the proliferation of the BMSCs showed no significant changes compared to the control group after TGF-β1,IGF-1,or GDF-7 treatment.However,TGF-β1 and GDF-7 could increase the cell proliferation in the 3D culture.Strangely,we also found more dead cells in the BMSC-collagen sponge constructs that were treated with TGF-β1.Moreover,TGF-β1 promoted more collagen deposition in both the 2D and 3D cultures.CONCLUSION Collagen sponge-based 3D culture with TGF-β1 enhances the responsiveness of the proliferation and tenogenic differentiation of rat BMSCs.

Influence of bone morphogenetic proteins-2 and strontium chloride on the human umbilical cord mesenchymal stem cells proliferation and osteogenic differentiation

Objective To study the effects of combination of bone morphogenetic protein-2 (BMP-2) and strontium chloride on proliferation and osteogenic differentiation of human umbilical cord mesenchymal stem cells(hUCM-SCs)in vitro culture.

Metabolic and proteostatic differences in quiescent and active neural stem cells

Adult neural stem cells are neurogenesis progenitor cells that play an important role in neurogenesis.Therefore,neural regeneration may be a promising target for treatment of many neurological illnesses.The regenerative capacity of adult neural stem cells can be chara cterized by two states:quiescent and active.Quiescent adult neural stem cells are more stable and guarantee the quantity and quality of the adult neural stem cell pool.Active adult neural stem cells are chara cterized by rapid proliferation and differentiation into neurons which allow for integration into neural circuits.This review focuses on diffe rences between quiescent and active adult neural stem cells in nutrition metabolism and protein homeostasis.Furthermore,we discuss the physiological significance and underlying advantages of these diffe rences.Due to the limited number of adult neural stem cells studies,we refe rred to studies of embryonic adult neural stem cells or non-mammalian adult neural stem cells to evaluate specific mechanisms.

An overview of autophagy in the differentiation of dental stem cells

Dental stem cells(DSCs)have attracted significant interest as autologous stem cells since they are easily accessible and give a minimal immune response.These properties and their ability to both maintain self-renewal and undergo multi-lineage differentiation establish them as key players in regenerative medicine.While many regulatory factors determine the differentiation trajectory of DSCs,prior research has predominantly been based on genetic,epigenetic,and molecular aspects.Recent evidence suggests that DSC differentiation can also be influenced by autophagy,a highly conserved cellular process responsible for maintaining cellular and tissue homeostasis under various stress conditions.This comprehensive review endeavors to elucidate the intricate regulatory mechanism and relationship between autophagy and DSC differentiation.To achieve this goal,we dissect the intricacies of autophagy and its mechanisms.Subsequently,we elucidate its pivotal roles in impacting DSC differentiation,including osteo/odontogenic,neurogenic,and angiogenic trajectories.Furthermore,we reveal the regulatory factors that govern autophagy in DSC lineage commitment,including scaffold materials,pharmaceutical cues,and the extrinsic milieu.The implications of this review are far-reaching,underpinning the potential to wield autophagy as a regulatory tool to expedite DSC-directed differentiation and thereby promote the application of DSCs within the realm of regenerative medicine.

Growth and differentiation of neural stem cells in a three-dimensional collagen gel scaffold

Collagen protein is an ideal scaffold material for the transplantation of neural stem cells. In this study rat neural stern cells were seeded into a three-dimensional collagen gel scaffold, with suspension cultured neural stem cells being used as a control group. Neural stem cells, which were cultured in medium containing epidermal growth factor and basic fibroblast growth factor, actively expanded and formed neurospheres in both culture groups. In serum-free medium conditions, the processes extended from neurospheres in the collagen gel group were much longer than those in the suspension culture group. Immunofluorescence staining showed that neurespheres cultured in collagen gels were stained positive for nestin and differentiated cells were stained positive for the neuronal marker βIII-tubulin, the astrocytic marker glial fibrillary acidic protein and the oligodendrocytic marker 2＇,3＇-cyclic nucleotide 3＇-phosphodiesterase. Compared with neurospheres cultured in suspension, the differentiation potential of neural stem cells cultured in collagen gels increased, with the formation of neurons at an early stage. Our results show that the three-dimensional collagen gel culture system is superior to suspension culture in the proliferation, differentiation and process outgrowth of neural stem cells.

miR-23a/b regulates the balance between osteoblast and adipocyte differentiation in bone marrow mesenchymal stem cells

Age-related osteoporosis is associated with the reduced capacity of bone marrow mesenchymal stem cells （BMSCs） to differentiate into osteoblasts instead of adipocytes. However, the molecular mechanisms that decide the fate of BMSCs remain unclear. In our study, microRNA-23a, and microRNA-23b （miR-23a/b） were found to be markedly downregulated in BMSCs of aged mice and humans. The overexpression of miR-23a/b in BMSCs promoted osteogenic differentiation, whereas the inhibition of miR-23a/b increased adipogenic differentiation. Transmembrane protein 64 （Tmem64）, which has expression levels inversely related to those of miR-23a/b in aged and young mice, was identified as a major target of miR-23a/b during BMSC differentiation. In conclusion, our study suggests that miR-23a/b has a critical role in the regulation of mesenchymal lineage differentiation through the suppression of Tmem64.

Beneficial effects of BV2 cell on proliferation and neuron-differentiating of mesenchymal stem cells in the circumstance of injured PC12 cell supernatant

Objective The microglias is the representative of immune cells in the brain. It plays dual roles of both repairing and damaging in injured nervous system, and works as an inevitable component of the circumstance of injured neurons. This study was aiming at the effects of the microglias on the biological activities of mesenchymal stem cells （MSCs） in the circumstance of injured neurons. Methods MSCs were obtained by primary culture. We adopted PC12 cells （PC12） and BV2 cells （BV2） to substitute for neurons and microglias, respectively. PC12 were injured by aged Aβ1-40 and the supernatant of the injured PC12 was used to set up the circumstance of injured neurons. Transwells were used for co-culture of BV2 and MSCs, which allowed the independent detection of cells after co-culture. Immunofluorescence was used to identify MSCs and neuron-differentiating cells with CD44 and neuron specific enolase （NSE） staining, respectively. MTT assay was adopted to measure the proliferation. Results In the circumstance of both BV2 presence and injured PC 12 supernatant incubation, either the proliferation or the differentiation of MSCs reached the highest, which seemed to be contradictory, but we gave our explanations. With the BV2 co-culture, the proliferation of MSCs tend to be higher, but the neuron-differentiating MSCs were similar to those incubated without BV2 co-culture either in normal or injured in PC12 supernatant. With the incubation of injured PC12 supernatant, the neuron-differentiating cells were significantly higher than that of control （P 〈 0.05）. Conclusion In the circumstance of injured neurons, microlgias tend to promote the MSCs proliferation. Although not helpful in neuron-differentiating, microglias did not exert any negative effect either.

miR-103-3p targets Ndel1 to regulate neural stem cell proliferation and differentiation

The regulation of adult neural stem cells(NSCs) is critical for lifelong neurogenesis. MicroRNAs(miRNAs) are a type of small, endogenous RNAs that regulate gene expression post-transcriptionally and influence signaling networks responsible for several cellular processes. In this study, mi R-103-3 p was transfected into neural stem cells derived from embryonic hippocampal neural stem cells. The results showed that mi R-103-3 p suppressed neural stem cell proliferation and differentiation, and promoted apoptosis. In addition, mi R-103-3 p negatively regulated Nud E neurodevelopment protein 1-like 1(Ndel1) expression by binding to the 3′ untranslated region of Ndel1. Transduction of neural stem cells with a lentiviral vector overexpressing Ndel1 significantly increased cell proliferation and differentiation, decreased neural stem cell apoptosis, and decreased protein expression levels of Wnt3 a, β-catenin, phosphor-GSK-3β, LEF1, c-myc, c-Jun, and cyclin D1, all members of the Wnt/β-catenin signaling pathway. These findings suggest that Ndel1 is a novel mi R-103-3 p target and that mi R-103-3 p acts by suppressing neural stem cell proliferation and promoting apoptosis and differentiation. This study was approved by the Animal Ethics Committee of Nantong University, China(approval No. 20200826-003) on August 26, 2020.