Histone variant H3.3 and its functions in reprogramming.

Histones are a class of evolutionarily conserved nuclear proteins. Histone octamer wrapped by DNA sequence forms the nucleosome, the basic building blocks of eukaryotic chromatin. The nucleosomes keep the DNA in a condensed state, maintain the integrity of the genome, and ensure proper DNA replication, transcription, recombination and repair. Nucleosomes can regulate the biological processes of the cell through a number of distinct post-translational modifications (PTMs) and turnovers of histone variants. Although the histone H3 variant H3.3 differs from the canonical histone H3 by only a few amino acids, it could be incorporated into distinct chromatin regions by specific chaperones and exert diverse functions on the chromatin. Importantly, H3.3 is also an essential maternal factor, and plays a key role in cellular reprogramming during fertilization and somatic cell nuclear transfer. In this review, we summarize the structural properties and enrichment pattern of H3.3, and explore the specific chaperones involved in the H3.3-mediated cellular reprogramming. We hope to provide some insights on new means to improve the efficiency of somatic cell reprogramming and lay the foundation for its potential applications.

Lnc2Meth: a manually curated database of regulatory relationships between long non-coding RNAs and DNA methylation associated with human disease.

Lnc2Meth (http://www.bio-bigdata.com/Lnc2Meth/), an interactive resource to identify regulatory relationships between human long non-coding RNAs (lncRNAs) and DNA methylation, is not only a manually curated collection and annotation of experimentally supported lncRNAs-DNA methylation associations but also a platform that effectively integrates tools for calculating and identifying the differentially methylated lncRNAs and protein-coding genes (PCGs) in diverse human diseases. The resource provides: (i) advanced search possibilities, e.g. retrieval of the database by searching the lncRNA symbol of interest, DNA methylation patterns, regulatory mechanisms and disease types; (ii) abundant computationally calculated DNA methylation array profiles for the lncRNAs and PCGs; (iii) the prognostic values for each hit transcript calculated from the patients clinical data; (iv) a genome browser to display the DNA methylation landscape of the lncRNA transcripts for a specific type of disease; (v) tools to re-annotate probes to lncRNA loci and identify the differential methylation patterns for lncRNAs and PCGs with user-supplied external datasets; (vi) an R package (LncDM) to complete the differentially methylated lncRNAs identification and visualization with local computers. Lnc2Meth provides a timely and valuable resource that can be applied to significantly expand our understanding of the regulatory relationships between lncRNAs and DNA methylation in various human diseases.

Association between hyperpolarization-activated channel in interstitial cells of Cajal and gastrointestinal dysmotility induced by malignant ascites.

Advanced malignant ascites is accompanied by gastrointestinal dysmotility, and patients often feel abdominal pain, abdominal distention, nausea and constipation. Gastrointestinal dysmotility is not only painful for the patients, but it reduces the absorption of nutrients and affects the physical recovery of patients with malignant ascites. It is reported that changes in interstitial cells of Cajal (ICCs) are responsible for the gastrointestinal dysmotility induced by malignant ascites, but the mechanism is not completely understood. The present study observed a significantly decreased expression of ion channels, including hyperpolarization-activated cyclic nucleotide-gated potassium channel 2 (HCN2) and cyclic adenosine monophosphate, in the condition of malignant ascites. Using electrophysiology, it was identified that malignant ascites led to lower amplitude and slower frequency signals in cells of the small intestine. In addition, when ICCs were cultured with malignant ascites in vitro, the expression of HCN2 of ICCs was significantly reduced, and the data of flow cytometry revealed that the Ca2+ concentration of ICCs was also decreased. The results of electron microscopy analysis demonstrated the nuclei of ICCs were pyknotic, and the processes of ICCs were reduced in malignant ascites. The present study suggests the small intestinal dysmotility caused by malignant ascites may be associated with changes in HCN2 of ICCs, which offers a potential therapeutic target for gastrointestinal dysmotility in advanced malignant ascites.

Morphological changes and germ layer formation in the porcine embryos from days 7-13 of development.

Morphogenesis and identification of embryonic differentiation in porcine embryos are crucial issues for developmental biology and laboratory animal science. The current paper presents a study on the asynchronous development of hatched porcine embryos from days 7 to 13 post-insemination. Examination of semi-thin sections of the hypoblast showed that it had characteristics similar to those of the mouse anterior visceral endoderm during embryonic disc formation. Also, a cavity appeared in the epiblast, which was similar to a mouse proamniotic cavity. With the gradual disappearance of Rauber's layer, the cavity opened and contacted the external environment directly, all of which formed the embryonic disc. To confirm the differentiation characteristics, we performed immunohistochemical analyses and showed that GATA6 was detected clearly in parietal endoderm cells during embryonic disc establishment. OCT4 was expressed in the inner cell mass (ICM) and trophoblast of hatched blastocysts and in the epiblast during formation of the embryonic disc. However, OCT4 showed comparatively decreased expression in the posterior embryonic disc, primitive streak and migrating cells. SOX2 was present in the ICM and epiblast. Therefore, both SOX2 and OCT4 can be used as markers of pluripotent cells in the porcine embryonic disc. At the start of gastrulation, staining revealed VIMENTIN in the posterior of the embryonic disc, primitive streak and in migrating cells that underlay the embryonic disc and was also expressed in epiblast cells located in the anterior primitive streak. Together with serial sections of embryos stained by whole mount immunohistochemistry, the mesoderm differentiation pattern was shown as an ingression movement that took place at the posterior of the embryonic disc and with bilateral migration along the embryonic disc borders.

The effects of harvesting media on biological characteristics and repair potential of neural stem cells after traumatic brain injury.

Various solutions are utilized widely for the isolation, harvesting, sorting, testing and transplantation of neural stem cells (NSCs), whereas the effects of harvesting media on the biological characteristics and repair potential of NSCs remain unclear. To examine some of these effects, NSCs were isolated from cortex of E14.5 mice and exposed to the conventional harvesting media [0.9% saline (Saline), phosphate-buffered saline (PBS) or artificial cerebrospinal fluid (ACSF)] or the proliferation culture medium (PCM) for different durations at 4°C. Treated NSCs were grafted by in situ injection into the lesion sites of traumatic brain injury (TBI) mice. In vitro, harvesting media-exposed NSCs displayed time-dependent reduction of viability and proliferation. S phase entry decreased in harvesting media-exposed cells, which was associated with upregulation of p53 protein and downregulation of cyclin E1 protein. Moreover, harvesting media exposure induced the necrosis and apoptosis of NSCs. The levels of Fas-L, cleaved caspase 3 and 8 were increased, which suggests that the death receptor signaling pathway is involved in the apoptosis of NSCs. In addition, exposure to Saline did not facilitate the neuronal differentiation of NSCs, suggesting that Saline exposure may be disadvantageous for neurogenesis. In vivo, NSC-mediated functional recovery in harvesting media-exposed NSC groups was notably attenuated in comparison with the PCM-exposed NSC group. In conclusion, harvesting media exposure modulates the biological characteristics and repair potential of NSCs after TBI. Our results suggest that insight of the effects of harvesting media exposure on NSCs is critical for developing strategies to assure the successful long-term engraftment of NSCs.

Adenosine receptor expression in a rat model of experimental autoimmune myasthenia gravis.

Extracellular adenosine is an essential negative regulator of immune reactions that acts by signaling via 4 distinct adenosine receptors. We evaluated adenosine receptor expression in Lewis rats presenting with experimental autoimmune myasthenia gravis (EAMG) to determine whether the expression of adenosine receptors are changed in the development and progression of EAMG. Lymphocyte A1AR and A2AAR mRNA and protein levels from lymphocytes harvested from the lymph nodes, spleen, and peripheral blood mononuclear cells (PBMCs) of EAMG rats were decreased. A modest but not significant increase in A2BAR levels was observed in EAMG lymphocytes harvested from lymph nodes and PBMCs. No changes in A3AR expression were observed in lymphocytes harvested from lymph nodes, spleen, or PBMCs following EAMG induction. Results presented in this report showed that the expression levels and the distribution pattern of adenosine receptors were altered in EAMG lymphocytes.

Lack of association between the G+2044A polymorphism of interleukin-13 gene and chronic obstructive pulmonary disease: a meta-analysis.

Numerous studies have investigated association of interleukin-13 (IL-13) G+2044A polymorphism with COPD susceptibility; however, the results were inconsistent and inconclusive. To evaluate the association between the IL-13 G+2044A polymorphism and susceptibility to COPD, a meta-analysis of published case-control studies was performed. Based on PubMed and Chinese database, this research selected studies that examined the association of the IL-13 G+2044A polymorphism with COPD. A genetic model-free approach was used to assess whether the combined data showed this association. Then a subgroup analysis was also performed, with stratifications for race, study design, and sample size. Six studies (total 1,213 COPD patients and 801 control subjects) for the IL-13 G+2044A polymorphism with COPD were included in the meta-analysis (G- vs A-allele: OR 1.12, 95 % CI 0.96-1.32, P = 0.15; genotypes GG+GA vs genotype AA: OR 0.99, 95 % CI 0.49-2.00, P = 0.98; genotype GG vs genotypes GA+AA: OR 1.18, 95 % CI 0.97-1.44, P = 0.09; genotype GA vs genotypes GG+AA: OR 0.85, 95 % CI 0.70-1.04, P = 0.11). This meta-analysis demonstrates that the IL-13 G+2044A polymorphism does not confer susceptibility to COPD. More detailed data about individual and environment, larger sample sizes with unbiased genotyping methods and matched controls in different populations are required.

Selection and expression profiles of reference genes in mouse preimplantation embryos of different ploidies at various developmental stages.

Real-time reverse transcription quantitative polymerase chain reaction (qPCR) has become the most frequently used system for studies of gene expression. Many studies have provided reliable evidence that the transcription levels of reference genes are not constant at different developmental stages and in different experimental conditions. However, suitable reference genes which are stably expressed in polyploid preimplantation embryos of different developmental stages have not yet been identified. Therefore, it is critical to verify candidate reference genes to analyze gene expression accurately in both diploid and polyploid embryos. We examined the expression levels of 12 candidate reference genes in preimplantation embryos of four different ploidies at six developmental stages. Stability analysis of the reference genes was performed by four independent software programs, and the stability of three genes was evaluated by comparison with the Oct4 expression level during preimplantation development in diploid embryos. The expression levels of most genes in the polyploid embryos were higher than that in the diploid embryos, but the increasing degree were disproportionate with the ploidies. There were no significant difference in reference gene expressions among embryos of different ploidies when they reached the morula stage, and the expression level remained flat until the blastocyst stage. Ubc, Ppia, and Pgk1 were the three most stable reference genes in diploid and polyploid embryos.

Comparison of reprogramming genes in induced pluripotent stem cells and nuclear transfer cloned embryos.

The most effective reprogramming methods, somatic cell nuclear transfer (SCNT) and induced pluripotent stem cells (iPSCs), are widely used in biological research and regenerative medicine, yet the mechanism that reprograms somatic cells to totipotency remains unclear and thus reprogramming efficiency is still low. Microarray technology has been employed in analyzing the transcriptomes changes during iPS reprogramming. Unfortunately, it is difficult to obtain enough DNA from SCNT reconstructed embryos to take advantage of this technology. In this study, we aimed to identify critical genes from the transcriptional profile for iPS reprogramming and compared expression levels of these genes in SCNT reprogramming. By integrating gene expression information from microarray databases and published studies comparing somatic cells with either miPSCs or mouse embryonic stem cells (ESCs), we obtained two lists of co-upregulated genes. The gene ontology (GO) enriched analysis of these two lists demonstrated that the reprogramming process is associated with numerous biological processes. Specifically, we selected 32 genes related to heterochromatin, embryonic development, and cell cycle from our co-upregulated gene datasets and examined the gene expression level in iPSCs and SCNT embryos by qPCR. The results revealed that some reprogramming related genes in iPSCs were also expressed in SCNT reprogramming. We established the network of gene interactions that occur with genes differentially expressed in iPS and SCNT reprogramming and then performed GO analysis on the genes in the network. The network genes function in chromatin organization, heterochromatin, transcriptional regulation, and cell cycle. Further researches to improve reprogramming efficiency, especially in SCNT, will focus on functional studies of these selected genes.

Association between the interleukin-4, interleukin-13 polymorphisms and asthma: a meta-analysis.

A numbers studies had been reported that the polymorphisms in the Interleukin 4 (IL-4) and Interleukin 13 (IL-13) genes were associated with susceptibility to asthma. However, the results were inconsistent and inconclusive. We carried out a meta-analysis of case-control genetic association studies to assess whether the combined data showed this association by using a genetic model-free approach. Thirty studies (total 12,781 asthma and 11,500 controls) for the IL-4 C-33T and C-589T, IL-13 C-1112T and G+2044A with asthma were included in the meta-analysis. The results indicated that there were an association between the IL-4 C-33T (P = 0.006) and C-589T (P = 0.04), IL-13 C-1112T (P = 0.002) and G+2044A (P = 0.04) and susceptibility to asthma. And the definition of asthma subgroup meta-analysis demonstrates that the IL-4 C-33T is not associated with nonatopic or atopic, and IL-4 C-589T and IL-13 C-1112T polymorphisms are not associated with atopic. In the ethnicity subgroup meta-analysis, the IL-4 -589T (P = 0.003) and the IL-13 -1112T (P < 0.00001) alleles are associated with asthma among Caucasian, but not on the IL-13 +2044A allele. In conclusion, IL-4 C-33T and C-589T, IL-13 C-1112T and G+2044A could be proposed as asthma susceptible SNPs. Further investigation in larger studies and meta-analysis is required.

Activation of the adenosine A2A receptor attenuates experimental autoimmune myasthenia gravis severity.

The adenosine A2A receptor (A2AR) is the major cellular adenosine receptor commonly associated with immunosuppression. Here, we investigated whether A2AR activation holds the potential for impacting the severity of experimental autoimmune myasthenia gravis (EAMG) induced following immunization of Lewis rats with the acetylcholine receptor (AChR) R97-116 peptide. This report demonstrates reduced A2AR expression by both T cells and B cells residing in spleen and lymph nodes following EAMG induction. A2AR stimulation inhibited anti-AChR antibody production and proliferation of AChR-specific lymphocytes in vitro. Inhibition was blocked with the A2AR antagonists or protein kinase A inhibitor. We also determined that the development of EAMG was accompanied by a T-helper cell imbalance that could be restored following A2AR stimulation that resulted in increased Treg cell levels and a reduction in Th1-, Th2-, and Th17-cell subtypes. An EAMG-preventive treatment regimen was established that consisted of (2-(p-(2-carbonylethyl)phenylethylamino)-5-N-ethylcarboxamidoadenosine) (CGS21680; A2AR agonist) administration 1 day prior to EAMG induction. Administration of CGS21680 29 days post EAMG induction (therapeutic treatment) also ameliorated disease severity. We conclude that A2AR agonists may represent a new class of compounds that can be developed for use in the treatment of myasthenia gravis or other T-cell- and B-cell-mediated autoimmune diseases.

Cytochalasin B treatment of mouse oocytes during intracytoplasmic sperm injection (ICSI) increases embryo survival without impairment of development.

Intracytoplasmic sperm injection (ICSI) is a technique commonly used in clinical and research settings. In mouse oocytes, conventional ICSI has a poor survival rate caused by a high level of lysis. Cytochalasin B (CB) is a toxic microfilament-inhibiting agent that is known to relax the cytoskeleton and enhance the flexibility of oocytes. CB has been used widely in nuclear transfer experiments to improve the success rate of the micromanipulation, however information describing the use of CB in ICSI is limited. Here, we demonstrated that the addition of 5 µg/ml CB to the manipulation medium of ICSI procedure significantly improved the survival rate of the ICSI embryos (80.74% vs. 89.50%, p < 0.05), and that there was no harm for the in vitro or in vivo development. The birth rates and birth weights were not significantly different between the CB-treated and -untreated groups. Interestingly, the microfilaments of the ICSI embryos were almost undetectable immediately after CB treatment; however, they gradually re-appeared and had fully recovered to the normal level 2 h later. Moreover, CB did not disturb spindle rotation, second polar body formation or pronuclei migration, and had no effect on the microtubules. We thus conclude that ICSI manipulation in CB-containing medium results in significantly improved survival rate of mouse ICSI embryos, and that short-term treatment with CB during ICSI manipulation does not have adverse effects on the development of ICSI embryos.

ApoER2 and VLDLR in the developing human telencephalon.

The Reelin-Dab1 signaling pathway plays a crucial role in regulating the migration and position of cortical neurons during the development of the cerebral cortex. Mutation in Reelin may result in severe developmental disorders such as autosomal recessive lissencephaly. Apolipoprotein E receptor type-2 (ApoER2) and very low-density lipoprotein receptor (VLDLR) are canonical receptors of Reelin, through which extracellular Reelin activates the intracellular adapter, Disabled1(Dab1), and subsequently interacts with other molecules. Although it is widely accepted that ApoER2 and VLDLR are indispensable components of the Reelin signaling pathway, little is known of their expression pattern in the laminated developing human brain. Here, we collected 18 cases of human fetal brains of 6-18 gestational weeks (GW) old and examined the expression of ApoER2 and VLDLR in the their telencephalon using immunocytochemical staining. We found that both receptors were absent in the preplate (PP) and the earliest stage of the cortical plate (CP). In later stages of CP development, ApoER2 was expressed earlier than VLDLR in the migrating neurons. Thus, the Reelin-Dab1 signaling pathway may not be involved in the formation of the preplate and deep layers of the CP. Instead, the pathway may act on neurons that are destined to form the more superficial layers of the CP. In addition, the pathway required ApoER2 only rather than both ApoER2 and VLDLR at the initiation of activity.

Generation of dorsal spinal cord GABAergic neurons from mouse embryonic stem cells.

Developmental signaling molecules involved in dorsal patterning of the spinal cord have been identified in vivo; however, studies have not produced specific functional dorsal spinal cord neurons in vitro. We present here differentiation of R1 embryonic stem (ES) cells into GABAergic dorsal spinal cord neurons by sequential treatment with developmental signaling molecules. We found that retinoic acid, Bmp4 altered the specification of neural progenitors and instructed neural fate when applied at distinct stages of development. High concentration of retinoic acid initiated caudal patterning during early differentiation; Bmp4 induced dorsal development. The combination of retinoic acid and different concentration Bmp4 controlled the differing regional progenitors of spinal cord. Low-concentration Bmp4 and high concentration of retinoic acid-treated embryoid bodies resulted in the differentiation of GABAergic neurons. In summary, we demonstrate this simple treatment paradigm produced simple dorsal spinal cord neurons, which could be utilized for developmental and preclinical studies.

RAD51 G135C polymorphism is associated with breast cancer susceptibility: a meta-analysis involving 22,399 subjects.

Several studies have investigated the associations between RAD51 G135C polymorphism and the susceptibility to breast cancer, but results have been inconclusive. In order to derive a more precise estimation of the relationship, a meta-analysis was performed. A total of 17 case control studies, including 12,153 cases and 10,245 controls, were selected. Overall, significant decreased risk was found for the additive model (OR = 0.995, 95% CI = 0.991-0.998) and dominant model (OR = 0.994, 95% CI = 0.991-0.998). In the subgroup analysis by ethnicity, statistically significantly decreased risk was found in Asians (additive model: OR = 0.977, 95% CI = 0.954-1.000 and dominant model: OR = 0.981, 95% CI = 0.963-1.000). In conclusion, this meta-analysis suggests that the RAD51 G135C polymorphism is a low-penetrant risk factor for developing breast cancer.

The distribution and expression of claudin-5 and occludin at the rat blood-optic nerve barrier after borneol treatment.

The purpose of this study is to investigate the distribution and expression of the tight junction membrane proteins, claudin-5 and occludin, in rat blood-optic nerve barrier after borneol treatment. Seventy-two female Wistar rats were randomly divided into the borneol gastric lavage group and the equal volume solvent gastric lavage control group. The bilateral optic nerve from the retrobulbar region to the optic chiasma was collected from the rats in the two groups before gastric lavage and at 30 min, 1, 2, 4, and 8 h after gastric lavage. The distribution and expression of claudin-5 and occludin were detected using immunofluorescence staining, Western blotting, and reverse transcription polymerase chain reaction (RT-PCR). Results showed that claudin-5 translocated from the cell membrane to the cytoplasm at 30 min following initiation of borneol treatment, and this translocation peaked at 1 h. During this period of time, a small amount of occludin also translocated from the cell membrane to the cytoplasm. Four hours after initiation of treatment, claudin-5 and occludin levels in the cytoplasm began to decrease and were restored to their normal pattern 8 h after initiation of treatment. There were no significant differences in the levels of claudin-5 or occludin before or after treatment in either group. It was concluded that claudin-5 and occludin translocate within cells of the rat blood-optic nerve barrier after borneol treatment, and this translocation was reversible. Claudin-5 may play a potential role in permeability of the blood-optic nerve barrier following borneol treatment.

Icariin induces mouse embryonic stem cell differentiation into beating functional cardiomyocytes.

Icariin, the primary active component of Epimedium extracts, has recently been shown to induce cardiomyocyte differentiation of murine embryonic stem (mES) cells in vitro. However, as these cardiomyocytes were not functionally characterized, the potential application of icariin-induced cardiomyocytes in clinical practice remains unclear. Therefore, in this study, we characterized the structure and function of icariin-induced cardiomyocytes to evaluate their potential application in transplantation for cardiac failure treatment. mES cells were cultured as embryoid bodies (EBs) via the direct suspension method in the presence of icariin. The protein expression profiles and ultrastructural characteristics of mES cell-derived cardiomyocytes were then characterized by immunofluorescence and transmission electron microscopy, respectively. In addition, the expression of cardiac-specific and calcium handling genes was detected by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Cardiomyocytes induced by icariin treatment expressed the cardiac-specific proteins myosin light chain-1v (MLC1v), atrial natriuretic polypeptide (ANP), and cardiac troponin I (cTnI). Furthermore, these cells appeared to possess myofibrils organized into mature sarcomeres that had formed A and I bands. In addition, icariin treatment upregulated the mRNA levels of MLC1v, ANP, cTnI, calsequestrin (CSQ), and sodium-calcium exchanger (NCX) in these cells. Icariin induces the differentiation of mES cells into beating cardiomyocytes with normal structure and function. Therefore, these cells may have promising applications in cardiac cell therapy or tissue engineering.

RA induces the neural-like cells generated from epigenetic modified NIH/3T3 cells.

Recently, differentiated somatic cells had been reprogrammed to pluripotential state in vitro, and various tissue cells had been elicited from those cells. Epigenetic modifications allow differentiated cells to perpetuate the molecular memory needed for the cells to retain their identity. DNA methylation and histone deacetylation are important patterns involved in epigenetic modification, which take critical roles in regulating DNA expression. In this study, we dedifferentiated NIH/3T3 fibroblasts by 5-aza-2-deoxycytidine (5-aza-dC) and Trichstatin A (TSA) combination, and detected gene expression pattern, DNA methylation level, and differentiation potential of reprogrammed cells. As the results, embryonic marker Sox2, klf4, c-Myc and Oct4 were expressed in reprogrammed NIH/3T3 fibroblasts. Total DNA methylation level was significant decreased after the treatment. Moreover, exposure of the reprogrammed cells to all trans-retinoic acid (RA) medium elicited the generation of neuronal class IIIbeta-tubulin-positive, neuron-specific enolase (NSE)-positive, nestin-positive, and neurofilament light chain (NF-L)-positive neural-like cells.

ES cell extract-induced expression of pluripotent factors in somatic cells.

Reprogramming of somatic cells was induced by ES cell-free extract. The system relied on the transient uptake of regulatory components from a nuclear and cytoplasmic extract derived from ES cells by the nucleus of a reversibly permeabilized NIH3T3 cell. NIH3T3 cells were permeabilized by streptolysin O (SLO). Reprogramming cell-free extracts were prepared by repeatedly freezing and thawing ES cells in liquid nitrogen. After incubation in the extract for 1 hr, permeabilized NIH3T3 cells were resealed by CaCl(2) and continually cultured for weeks to assess expression of ES cell specific markers. As we observed using FACS and fluorescence microscope, the optimal SLO concentration for permeabilizing NIH3T3 cells was 25 U. After 2 weeks of culture, the treated NIH3T3 cells began to express Nanog, c-Myc, Klf4, and 6 weeks later Oct4 was detectable. However, Sox2 was detected only after 8 weeks of culture. Differentiated somatic cells could be reprogrammed in ES extract in vitro, which provides a new approach to decreasing differentiation levels in somatic cells without disturbing the DNA sequences.

MSCs guide neurite directional extension and promote oligodendrogenesis in NSCs.

Previous studies have shown that mesenchymal stem cells (MSCs) enhance repair following injury or degenerative diseases in the central nervous system, but the underlying mechanisms remain unclear. The present study investigated the functional relationship between MSCs and neural stem cells (NSCs) using co-culture systems. Results demonstrated that MSCs promoted outgrowth and guided directional extension of NSC-derived neurites. The majority of neurites were oriented parallel along the MSC axis. Stripe assay results indicated that cell adhesion molecule and extracellular matrix, such as N-cadherin, fibronectin, and laminin, contributed to this effect. Furthermore, Western blot analysis revealed that phosphorylation of cAMP response element-binding protein (CREB) increased during this process. In addition, MSCs promoted differentiation of NSCs into oligodendrocytes via secreted soluble factors. The oligodendrocytes were distributed along the MSC surface in a regular pattern. This study demonstrated that MSC transplantation could be a potential strategy for treating central nervous system injuries.