Effects of FTY720 on Neural Cell Behavior in Two and Three-Dimensional Culture and in Compression Spinal Cord Injury.

Introduction: The present study aimed to evaluate the effects of FTY720 as a neuromodulatory drug on the behaviors of neural stem/progenitor cells (NS/PCs) in two-dimensional (2-D) and three-dimensional (3-D) cultures and in spinal cord injury (SCI). Methods: The NS/PCs isolated from the ganglionic eminence of the 13.5-day old embryos were cultured as free-floating spheres. The single cells obtained from the second passage were cultured in 96-well plates without any scaffold (2-D) or containing PuraMatrix (PM, 3-D) or were used for transplantation in a mouse model of compression SCI. After exposure to 0, 10, 50, and 100 nanomolar of FTY720, the survival, proliferation, and migration of the NS/PCs were evaluated in vitro using MTT assay, neurosphere assay, and migration assay, respectively. Moreover, the functional recovery, survival and migration capacity of transplanted cells exposure to 100 nanomolar FTY720 were investigated in SCI. Results: Cell survival and migration capacity increased after exposure to 50 and 100 nanomolar FTY720. In addition, higher doses of FTY720 led to the formation of more extensive and more neurospheres. Although this phenomenon was similar in both 2-D and 3-D cultures, PM induced better distribution of the cells in a 3-D environment. Furthermore, co-administration of FTY720 and NS/PCs 7 days after SCI enhanced functional recovery and both survival and migration of transplanted cells in the lesion site. Conclusions: Due to the positive effects of FTY720 on the behavior of NS/PCs, using them in combination therapies can be an appealing approach for stem cell therapy in CNS injury.

Local delivery of fingolimod through PLGA nanoparticles and PuraMatrix-embedded neural precursor cells promote motor function recovery and tissue repair in spinal cord injury.

Spinal cord injury (SCI) is a devastating clinical problem that can lead to permanent motor dysfunction. Fingolimod (FTY720) is a sphingosine structural analogue, and recently, its therapeutic benefits in SCI have been reported. The present study aimed to evaluate the therapeutic efficacy of fingolimod-incorporated poly lactic-co-glycolic acid (PLGA) nanoparticles (nanofingolimod) delivered locally together with neural stem/progenitor cells (NS/PCs) transplantation in a mouse model of contusive acute SCI. Fingolimod was encapsulated in PLGA nanoparticles by the emulsion-evaporation method. Mouse NS/PCs were harvested and cultured from embryonic Day 14 (E14) ganglionic eminences. Induction of SCI was followed by the intrathecal delivery of nanofingolimod with and without intralesional transplantation of PuraMatrix-encapsulated NS/PCs. Functional recovery, injury size and the fate of the transplanted cells were evaluated after 28 days. The nanofingolimod particles represented spherical morphology. The entrapment efficiency determined by UV-visible spectroscopy was approximately 90%, and the drug content of fingolimod loaded nanoparticles was 13%. About 68% of encapsulated fingolimod was slowly released within 10 days. Local delivery of nanofingolimod in combination with NS/PCs transplantation led to a stronger improvement in neurological functions and minimized tissue damage. Furthermore, co-administration of nanofingolimod and NS/PCs not only increased the survival of transplanted cells but also promoted their fate towards more oligodendrocytic phenotype. Our data suggest that local release of nanofingolimod in combination with three-dimensional (3D) transplantation of NS/PCs in the acute phase of SCI could be a promising approach to restore the damaged tissues and improve neurological functions.

Improvement of Rat Spinal Cord Injury Following Lentiviral Vector-Transduced Neural Stem/Progenitor Cells Derived from Human Epileptic Brain Tissue Transplantation with a Self-assembling Peptide Scaffold.

Spinal cord injury (SCI) is a disabling neurological disorder that causes neural circuit dysfunction. Although various therapies have been applied to improve the neurological outcomes of SCI, little clinical progress has been achieved. Stem cell-based therapy aimed at restoring the lost cells and supporting micromilieu at the site of the injury has become a conceptually attractive option for tissue repair following SCI. Adult human neural stem/progenitor cells (hNS/PCs) were obtained from the epileptic human brain specimens. Induction of SCI was followed by the application of lentiviral vector-mediated green fluorescent protein-labeled hNS/PCs seeded in PuraMatrix peptide hydrogel (PM). The co-application of hNS/PCs and PM at the SCI injury site significantly enhanced cell survival and differentiation, reduced the lesion volume, and improved neurological functions compared to the control groups. Besides, the transplanted hNS/PCs seeded in PM revealed significantly higher migration abilities into the lesion site and the healthy host tissue as well as a greater differentiation into astrocytes and neurons in the vicinity of the lesion as well as in the host tissue. Our data suggest that the transplantation of hNS/PCs seeded in PM could be a promising approach to restore the damaged tissues and improve neurological functions after SCI.

Stem cell therapy in patients with epilepsy: A systematic review.

PURPOSE: The existing evidence of the potential applications and benefits of stem cell transplantation (SCT) in people with epilepsy and also its adverse effects in humans were systematically reviewed. METHODS: MEDLINE (accessed from PubMed), Google Scholar, and Scopus from inception to August 17, 2020 were systematically reviewed for related published manuscripts. The following key words (in the title) were used: "stem cell" AND "epilepsy" OR "seizure". Articles written in English that were human studies on stem cell transplantation in people with epilepsy were all included. RESULTS: We could identify six related articles. Because of their different methodologies, performing a meta-analysis was not feasible; they included 38 adults and 81 pediatric patients together. Five studies were single-arm human studies; there were no serious adverse events in any of the studies. CONCLUSION: While stem cell transplantation seems like a promising therapeutic option for patients with drug-resistant epilepsy, data on its application is scarce and of low quality. For now, clinical stem cell-based interventions are not justified. Perhaps, in the future, there will be a rigorous and intensely scrutinized clinical trial protocol with informed consent that could provide enough scientific merit and could meet the required ethical standards.

Lentiviral vector-mediated transduction of adult neural stem/progenitor cells isolated from the temporal tissues of epileptic patients.

OBJECTIVES: Neural stem/progenitor cells (NS/PCs) hold a great potential for delivery of therapeutic agents into the injured regions of the brain. Efficient gene delivery using NS/PCs may correct a genetic defect, produce therapeutic proteins or neurotransmitters, and modulate enzyme activation. Here, we investigated the efficiency of a recombinant lentivirus vector expressing green fluorescent protein (GFP) for genetic engineering of human NS/PCs obtained during brain surgery on patients with medically intractable epilepsy. MATERIALS AND METHODS: NS/PCs were isolated from human epileptic neocortical tissues. Three plasmids (pCDH, psPAX2, pMD2.G) were used to make the virus. To produce the recombinant viruses, vectors were transmitted simultaneously into HEk-293T cells. The lentiviral particles were then used to transduce human NS/PCs. RESULTS: Our in vitro study revealed that lentivirus vector expressing GFP efficiently transduced about 80% of human NS/PCs. The expression of GFP was assessed as early as 3 days following exposure and remained persistent for at least 4 weeks. CONCLUSION: Lentiviral vectors can mediate stable, long-term expression of GFP in human NS/PCs obtained from epileptic neocortical tissues. This suggests lentiviral vectors as a potential useful tool in human NS/PCs-based gene therapy for neurological disorders, such as epilepsy.

Effects of neural stem cell-derived extracellular vesicles on neuronal protection and functional recovery in the rat model of middle cerebral artery occlusion.

Stroke imposes a long-term neurological disability with limited effective treatments available for neuronal recovery. Transplantation of neural stem cells (NSCs) is reported to improve functional outcomes in the animal models of brain ischemia. However, the use of cell therapy is accompanied by adverse effects, so research is growing to use cell-free extracts such as extracellular vesicles (EVs) for targeting brain diseases. In the current study, male Wistar albino rats (20 months old) were subjected to middle cerebral artery occlusion (MCAO). Then, EVs (30 µg) were injected at 2 hours after stroke onset via an intracerebroventricular (ICV) route. Measurements were done at day 7 post-MCAO. EVs administration reduced lesion volume and steadily improved spontaneous locomotor activity. EVs administration also reduced microgliosis (ionized calcium-binding adaptor molecule 1 (Iba1)+ cells) and apoptotic (terminal-deoxynucleotidyl transferase mediated nick end labelling [TUNEL]) positive cells and increased neuronal survival (neuronal nuclear (NeuN)+ cells) in the ischemic boundary zone (IBZ). However, it had no effect on neurogenesis within the sub-ventricular zone (SVZ) but decreased cellular migration toward the IBZ (doublecortin (DCX)+ cells). The results of this study showed neuroprotective and restorative mechanisms of NSC-EVs administration, which may offer new avenues for therapeutic intervention of brain ischemia. SIGNIFICANCE OF THE STUDY: Based on our results, EVs administration can effectively reduce microglial density and neuronal apoptosis, thereby steadily improves functional recovery after MCAO. These findings provide the beneficial effect of NSC-EVs as a new biological treatment for stroke.

Sustained release of silibinin-loaded chitosan nanoparticle induced apoptosis in glioma cells.

In this study, a chitosan nanoparticle formulation was synthesized for loading silibinin as a sustained-release drug system to evaluate its effects on apoptosis in C6 glioma cells. This synthesized nanoparticle was analyzed by measurement methods including Fourier transform infrared (FTIR), field emission-scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The formation and amorphization of nanoparticle were confirmed by FTIR and XRD analysis, respectively. The mean diameter of silibinin-loaded chitosan nanoparticles (SCNP) was 50 ± 7 and 188.6 ± 0.17 nm by using FE-SEM and DLS, respectively. In addition, the positive zeta potential of nanoparticles was +11.5. Rhodamine-conjugated SCNP analysis showed the internalization of silibinin to C6 glioma cells. The cytotoxicity assay indicated that the nanoformulation of silibinin was toxic to C6 glioma cells. Although SCNP significantly increased the expression of the both apoptotic genes in C6 cells, Bax and caspase3, it did not have any significant effect on the level of the antiapoptotic gene, Bcl2. In contrast, SCNP did not have any toxic effect on H9C2 cells. In conclusion, the results of the current study indicated that SCNP can be considered as a sustained-release drug system for future cell-based therapeutic strategies.

Switching from high-fat diet to foods containing resveratrol as a calorie restriction mimetic changes the architecture of arcuate nucleus to produce more newborn anorexigenic neurons.

PURPOSE: These days, obesity threatens the health for which one of the main interventions is calorie restriction (CR). Due to the difficulty of compliance with this treatment, CR mimetics such as resveratrol (RSV) have been considered. The present study compared the effects of RSV and CR on hypothalamic remodeling in a diet-switching experiment. METHODS: C57BL/6 male mice received high-fat diet (HFD) for 4 weeks, subsequently their diet switched to chow diet, HFD + RSV, chow diet + RSV or CR diet for a further 6 weeks. Body weight, fat accumulation, hypothalamic apoptosis and expression of trophic factors as well as generation and fate specification of newborn cells in arcuate nucleus (ARC) were evaluated. RESULTS: Switching diet to RSV-containing foods leading to weight and fat loss after 6 weeks. In addition, not only a significant reduction in apoptosis but also a considerable increase in production of newborn cells in ARC occurred following consumption of RSV-enriched diets. These were in line with augmentation of hypothalamic ciliary neurotrophic factor and leukemia inhibitory factor expression. Interestingly, RSV-containing diets changed the fate of newborn neurons toward generation of more proopiomelanocortin than neuropeptide Y neurons. The CR had effects similar to those of RSV-containing diets in the all-evaluated aspects besides neurogenesis in ARC. CONCLUSIONS: Although both RSV-containing and CR diets changed the fate of newborn neurons to create an anorexigenic architecture for ARC, newborn neurons were more available after switching to RSV-enriched diets. It can be consider as a promising mechanism for future investigations.

Cell injury and receptor expression in the epileptic human amygdala.

Neuropathological findings in the amygdala obtained from patients with mesial temporal lobe epilepsy (MTLE) indicate varying degrees of histopathological alterations, such as neuronal loss and gliosis. The mechanisms underlying cellular damage in the amygdala of patients with MTLE have not been fully elucidated. In the present study, we assess cellular damage, determine the receptor expression of major inhibitory and excitatory neurotransmitters, and evaluate the correlation between the expression of various receptors and cell damage in the basolateral complex and the centromedial areas in the amygdala specimens resected during brain surgery on 30 patients with medically intractable MTLE. Our data reveal an increased rate of cell damage and apoptosis as well as decreased expression levels of several GABAergic receptor subunits (GABAARα1, GABAARß3, and GABABR1) and GAD65 in the amygdalae obtained during epilepsy surgery compared to autopsy specimens. Analyses of the expression of glutamate excitatory receptor subunits (NR1, NR2B, mGluR1α, GluR1, and GluR2) reveal no significant differences between the epileptic amygdalae and autopsy control tissues. Furthermore, the increased occurrence of apoptotic cells in the amygdala is negatively correlated with the reduced expression of the studied GABAergic receptor subunits and GAD65 but is not correlated with the expression of excitatory receptors. The present data point to the importance of GABAergic neurotransmission in seizure-induced cell injury in the amygdala of patients with MTLE and suggest several GABA receptor subunits as potential druggable target structures to control epilepsy and its comorbid disorders, such as anxiety.

Generation of motor neurons from human amygdala-derived neural stem-like cells.

OBJECTIVES: Among several cell sources, adult human neural stem/progenitor cells (hNS/PCs) have been considered outstanding cells for performing mechanistic studies in in vitro and in vivo models of neurological disorders as well as for potential utility in cell-based therapeutic approaches. Previous studies addressed the isolation and culture of hNS/PCs from human neocortical and hippocampal tissues. However, little data are available on hNS/PCs obtained from the adult human amygdala. MATERIALS AND METHODS: The present study explored the capacity of the amygdala harvested from resected brain tissues of patients with medically refractory epilepsy to generate neurosphere-like bodies and motor neuron-like cells. RESULTS: Although the proliferation process was slow, a considerable amount of cells was obtained after the 3rd passage. In addition, the cells could generate motor neuron-like cells under appropriate culture conditions. CONCLUSION: Isolation and culture of these cells enable us to improve our knowledge of the role of the amygdala in some neurological and psychological disorders and provide a novel source for therapeutic cell transplantation.

Resveratrol promotes the arcuate nucleus architecture remodeling to produce more anorexigenic neurons in high-fat-diet-fed mice.

OBJECTIVE: Adult hypothalamic neurogenesis has been considered a central regulator of energy balance. Resveratrol (RSV), a natural polyphenol, influences the body fat mass and reduces the amount of adipose tissue. The present study was designed to evaluate the effect of RSV on dynamic of hypothalamic neurons in a diet-induced obesity model of mice. METHODS: Apoptosis, neurogenesis, the expression of the main trophic factors, and the fate of newborn cells were evaluated in the hypothalamus of adult male C57 BL/6 J mice fed a normal diet, a high-fat (HF) diet, or an HF diet supplemented with 400 mg/kg RSV (HF + RSV) for 6 wk. RESULTS: The HF diet caused an increase in neuronal apoptosis in the hypothalamus, which coincided with an increase in the number of newborn cells in the arcuate nucleus, suggesting that compensatory mechanisms developed to overcome deleterious effects of the HF diet. Addition of RSV to the HF diet enhanced the production of newborn cells in all studied regions of the hypothalamus. These changes were paralleled by enhancement of the expression of ciliary neurotrophic factor. Interestingly, a considerable proportion of newborn cells expressed neuropeptide Y in the arcuate nucleus of the HF group, and conversely, most of them differentiated to proopiomelanocortin neurons in HF + RSV mice. CONCLUSIONS: Diets rich in fat changed hypothalamic neuronal balance toward orexigenic versus anorexigenic neurons. Administration of RSV to the HF diet reversed this balance toward generation of anorexigenic neurons. These data point to the potential for RSV in regulation of body weight, possibly via modulation of hypothalamic neurogenesis.

A Novel Biopsy Method for Isolating Neural Stem Cells from the Subventricular Zone of the Adult Rat Brain for Autologous Transplantation in CNS Injuries.

Despite all attempts the problem of regeneration in damaged central nervous system (CNS) has remained challenging due to its cellular complexity and highly organized and sophisticated connections. In this regard, stem cell therapy might serve as a viable therapeutic approach aiming either to support the damaged tissue and hence to reduce the subsequent neurological dysfunctions and impairments or to replace the lost cells and re-establish damaged circuitries. Adult neural stem/progenitor cells (NS/PCs) are one of the outstanding cell sources that can be isolated from the subventricular zone (SVZ) of the lateral ventricles. These cells can differentiate into neurons, astrocytes, and oligodendrocytes. Implanting autologous NS/PCs will greatly benefit the patients by avoiding immune rejection after implantation, better survival, and integration with the host tissue. Developing safe and efficient methods in small animal models will provide us with the opportunity to optimize procedures required to achieve successful human autologous NS/PC transplantation in near future. In this chapter, a highly controlled and safe biopsy method for harvesting stem cell containing tissue from the SVZ of adult rat brain is introduced. Then, isolation and expansion of NS/PCs from harvested specimen as well as the techniques to verify proliferation and differentiation capacity of the resulting NS/PCs are discussed. Finally, a method for assessing the biopsy lesion volume in the brain is described. This safe biopsy method in rat provides a unique tool to study autologous NS/PC transplantation in different CNS injury models.

Preparing neural stem/progenitor cells in PuraMatrix hydrogel for transplantation after brain injury in rats: A comparative methodological study.

Cultivation of neural stem/progenitor cells (NS/PCs) in PuraMatrix (PM) hydrogel is an option for stem cell transplantation. The efficacy of a novel method for placing adult rat NS/PCs in PM (injection method) was compared to encapsulation and surface plating approaches. In addition, the efficacy of injection method for transplantation of autologous NS/PCs was studied in a rat model of brain injury. NS/PCs were obtained from the subventricular zone (SVZ) and cultivated without (control) or with scaffold (three-dimensional cultures; 3D). The effect of different approaches on survival, proliferation, and differentiation of NS/PCs were investigated. In in vivo study, brain injury was induced 45 days after NS/PCs were harvested from the SVZ and phosphate buffered saline, PM, NS/PCs, or PM+NS/PCs were injected into the brain lesion. There was an increase in cell viability and proliferation after injection and surface plating of NS/PCs compared to encapsulation and neural differentiation markers were expressed seven days after culturing the cells. Using injection method, transplantation of NS/PCs cultured in PM resulted in significant reduction of lesion volume, improvement of neurological deficits, and enhancement of surviving cells. In addition, the transplanted cells could differentiate in to neurons, astrocytes, or oligodendrocytes. Our results indicate that the injection and surface plating methods enhanced cell survival and proliferation of NS/PCs and suggest the injection method as a promising approach for transplantation of NS/PCs in brain injury.

Survival, proliferation, and migration of human meningioma stem-like cells in a nanopeptide scaffold.

OBJECTIVES: In order to grow cells in a three-dimensional (3D) microenvironment, self-assembling peptides, such as PuraMatrix, have emerged with potential to mimic the extracellular matrix. The aim of the present study was to investigate the influence of the self-assembling peptide on the morphology, survival, proliferation rate, migration potential, and differentiation of human meningioma stem-like cells (hMgSCs). MATERIALS AND METHODS: The efficacy of a novel method for placing hMgSCs in PuraMatrix (the injection approach) was compared to the encapsulation and surface plating methods. In addition, we designed a new method for measurement of migration distance in 3D cultivation of hMgSCs in PuraMatrix. RESULTS: Our results revealed that hMgSCs have the ability to form spheres in stem cell culture condition. These meningioma cells expressed GFAP, CD133, vimentin, and nestin. Using the injection method, a higher proliferation rate of the hMgSCs was observed after seven days of culture. Furthermore, the novel migration assay was able to measure the migration of a single cell alone in 3D environment. CONCLUSION: The results indicate the injection method as an efficient technique for culturing hMgSCs in PuraMatrix. Furthermore, the novel migration assay enables us to evaluate the migration of hMgSCs.

Self-Assembling Peptide Nanofiber Containing Long Motif of Laminin Induces Neural Differentiation, Tubulin Polymerization, and Neurogenesis: In Vitro, Ex Vivo, and In Vivo Studies.

Spinal cord injury (SCI) in humans stayed a ruining and healless disorder. Since longer laminin motif (CQAASIKVAV (CQIK)) better mimics conformation of native region in active site than isoleucine-lysine-valine-alanine-valine (IKVAV) and resulted in improved cellular response so, for the first time in this study, CQIK bounded with two glycines spacer and (RADA)4 as a self-assembling peptide nanofiber backbone (-CQIK) was used. The purpose of this study was to investigate the role of -CQIK in neural differentiation of human endometrial-derived stromal cells (hEnSCs) in vitro, tubulin polymerization ex vivo, and assess the supportive effect of this hydrogel in an animal model of chronic SCI. Results disclosed that proton concentration has direct effect on hEnSCs membrane damage but not on neuroblastoma cells. However, cell viability of neuroblastoma encapsulated into -CQIK was higher than hEnSCs at the concentration of 0.125 % v/w. Gene expression data confirmed neurogenesis, TH over-expression, and glial fibrillary acidic protein (GFAP) suppression eventually through α6 and ß1 integrin site. However, it revealed higher neurogenesis as compared to bone morrow homing peptides (BMHP). Although, Basso, Beattie, Bresnahan (BBB) score of chronic model of SCI in rat was higher than control and phosphate-buffered saline (PBS) group but significantly was less than BMHP group. However, -CQIK had induced neurite outgrowth and myelination and inhibited astrogliosis. Tubulin polymerization data using UV spectroscopy showed higher degree of polymerization. However, tubulin polymerization was dependent on nanofiber concentration. Based on our results, it might be concluded that peptidic nanofiber containing long motif of laminin holds great promise for spinal cord injury recovery with increment of neurogenesis and astrogliosis decrement.

Chimeric Self-assembling Nanofiber Containing Bone Marrow Homing Peptide's Motif Induces Motor Neuron Recovery in Animal Model of Chronic Spinal Cord Injury; an In Vitro and In Vivo Investigation.

To date, spinal cord injury (SCI) has remained an incurable disaster. The use of self-assembling peptide nanofiber containing bioactive motifs such as bone marrow homing peptide (BMHP1) as an injectable scaffold in spinal cord regeneration has been suggested. Human endometrial-derived stromal cells (hEnSCs) have been approved by the FDA for clinical application. In this regard, we were interested in investigating the role of BMHP1 in hEnSCs' neural differentiation in vitro and evaluating the supportive effects of this scaffold in rat model of chronic SCI. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), lactate dehydrogenase (LDH) release, 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay, real-time PCR, and immunocyotochemistry (ICC) were performed as a biocompatibility and neural differentiation evaluations on neuron-like hEnSC-derived cells encapsulated into nanofiber. Nanofiber was implanted into rats and followed by behavioral test, Nissl, luxol fast blue (LFB) staining and immunohistostaining (IHC). Results indicated that cell membrane of neuroblastoma cells were more sensitive than hEnSCs to concentration of proton and cell proliferation decreased with increase of concentration. This effect might be related to oxygen tension and elastic modules of scaffold. -BMHP1 nanofiber induced neural differentiation in hEnSC and decreased GFAP gene and protein as a marker of reactive astrocytes in vitro and in vivo. A reason for this finding might be related to the role of spacer number in induction of mechano-transduction signals. The presented study revealed the chimeric BMHP1 nanofiber induced higher axon regeneration and myelniation around the cavity and motor neuron function was encouraged to improve with less inflammatory response following SCI in rats. These effects were possibly due to nanostructured topography and mechano-transduction signals derived from hydrogel at low concentration.

Curcumin as a double-edged sword for stem cells: dose, time and cell type-specific responses to curcumin.

BACKGROUND: The beneficial effects of curcumin which includes its antioxidant, anti-inflammatory and cancer chemo-preventive properties have been identified. Little information is available regarding the optimal dose and treatment periods of curcumin on the proliferation rate of different sources of stem cells. METHODS: In this study, the effect of various concentrations of curcumin on the survival and proliferation of two types of outstanding stem cells which includes bone marrow stem cells (BMSCs) and adult rat neural stem/progenitor cells (NS/PCs) at different time points was investigated. BMSCs were isolated from bilateral femora and tibias of adult Wistar rats. NS/PCs were obtained from subventricular zone of adult Wistar rat brain. The curcumin (0.1, 0.5, 1, 5 and 10 µM/L) was added into a culture medium for 48 or 72 h. Fluorescent density of 5-bromo-2'-deoxyuridine (Brdu)-positive cells was considered as proliferation index. In addition, cell viability was assessed by MTT assay. RESULTS: Treatment of BMSCs with curcumin after 48 h, increased cell survival and proliferation in a dose-dependent manner. However, it had no effect on NSCs proliferation except a toxic effect in the concentration of 10 µM of curcumin. After a 72 h treatment period, BMSCs and NS/PCs survived and proliferated with low doses of curcumin. However, high doses of curcumin administered for 72 h showed toxic effects on both stem cells. CONCLUSIONS: These findings suggest that curcumin survival and proliferative effects depend on its concentration, treatment period and the type of stem cells. Appropriate application of these results may be helpful in the outcome of combination therapy of stem cells and curcumin.

Regulation of connexin 43 and microRNA expression via ß2-adrenoceptor signaling in 1321N1 astrocytoma cells.

Connexin 43 (Cx43) is the main gap junction protein in astrocytes and exerts the same effects on growth inhibition in astrocytoma and glioma as microRNA-146a (miR-146a) in glioma. ß2-adrenergic receptor (AR) signaling modulates Cx43 expression in myocytes via components downstream of protein kinase A (PKA) and exchange protein directly activated by cAMP (Epac). However, it remains to be elucidated how expression of Cx43 is modulated in astrocytes. In the present study, 1321N1 astrocytoma cells were treated with ß2-AR signaling agents in order to evaluate the expression of Cx43 and miRNAs. RNA and protein were extracted from the cells for use in reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. The results revealed that clenbuterol increased miR-146a level and upregulated Cx43 expression via cAMP/PKA at the mRNA and protein level. Pre-inhibition of adenyl cyclase decreased expression of Cx43 and miR-146a. PKA activation and overexpression of miR-146a in A-1321N1 cells increased the expression of Cx43. ß2-AR stimulation and 6Bnz, a PKA activator, suppressed oncomiRs miR-155 and miR-27a, while 8-(4-chlorophenylthio)-2'-O-methyladenosine-3',5'-cyclic monophosphate, an Epac activator, increased their levels. The current findings demonstrated that ß2-AR signaling has growth inhibitory effects via modulation of the cAMP/PKA pathway in A-1321N1 cells through increasing the expression level of Cx43 and miR-146a as well as decreasing miR-155 and miR-27a levels. Thus, stimulation of the ß2-AR and PKA signaling pathway may be a useful approach for astrocytoma therapy.

Thermogel nanofiber induces human endometrial-derived stromal cells to neural differentiation: In vitro and in vivo studies in rat.

Spinal cord injury (SCI) in humans remains a devastating and incurable disorder. The use of Matrigel, a hydrogel-mimicking extracellular matrix, has been suggested as a scaffold for spinal cord regeneration. Human endometrial-derived stromal cells (hEnSCs) are abundant and available in adult stem cells with low immunological incompatibility, which could be considered for cell replacement therapy. The purpose of this study was to investigate the role of Matrigel in neural differentiation of hEnSCs in vitro and assess the supportive effects of this hydrogel in an animal model of SCI. hEnSCs were isolated and encapsulated into nanofibrous thermogel and cell viability and cell membrane damage were assessed. Encapsulated hEnSCs into Matrigel were treated with neural differentiation medium for 21 days, and then neural genes and protein markers were analyzed using real time-PCR and immunocytochemistry. Matrigel was implanted into rats with SCI and followed for 42 days using a behavioral test. Our study revealed a higher cell viability and neural differentiation in the level of genes and proteins as well as lower cell membrane damage. Substantial recoveries of motor function were observed in animals receiving the Matrigel treatment. The treatment with Matrigel, nanofibrous scaffold, produced beneficial effects on functional recovery following SCI in rats, possibly via assimilation to cytoskeleton fiber, high surface/volume ratio, spatial interconnectivity and containing some adhesive molecules and growth factors, enhancement of anti-inflammation, anti-astrogliosis, neuronal extension, and neuronal regeneration effects.

A new and safe method for stereotactically harvesting neural stem/progenitor cells from the adult rat subventricular zone.

BACKGROUND: Adult neural stem/progenitor cells (NS/PCs) are one of the outstanding cell sources for therapeutic purposes in the central nervous system diseases. Autologous transplantation of NS/PCs still is a matter of controversy due to the safety issue as well as efficiency of harvesting these cells from the live mammalian brain subventricular zone (SVZ). NEW METHOD: In this new and safe method, a 16-guage semi-automatic biopsy needle was used stereotactically to remove a piece of SVZ. Then, the proliferation and differentiation capacity of obtained cells were assessed. In addition, the safety of the biopsy procedure was analyzed employing the Morris water maze, modified neurologic severity score, passive avoidance and open field tests. RESULTS: Despite being very small in size, the SVZ specimen could generate a large number of progeny with the ability to differentiate into neuronal and glial cells. The biopsy procedure introduced in this study did not have any impact on the behavioral and neurological processes. COMPARISON WITH EXISTING METHOD(S): existing SVZ biopsy methods were uncontrollable techniques which harvested brain tissue by aspiration using a syringe not a semi-automatic biopsy needle. Also, previous methods were not evaluated in terms of behavior and cognition. CONCLUSIONS: This study revealed a considerable safety and efficacy for the stereotactical removal of the adult rat SVZ to harvest NS/PCs for autologous transplantation.