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Schizophrenia is a severe psychiatric disorder of neurodevelopmental origin that affects around 1% of the world's population. Proteomic studies and other approaches have provided evidence of compromised cellular processes in the disorder, including mitochondrial function. Most of the studies so far have been conducted on postmortem brain tissue from patients, and therefore, do not allow the evaluation of the neurodevelopmental aspect of the disorder. To circumvent that, we studied the mitochondrial and nuclear proteomes of neural stem cells (NSCs) and neurons derived from induced pluripotent stem cells (iPSCs) from schizophrenia patients versus healthy controls to assess possible alterations related to energy metabolism and mitochondrial function during neurodevelopment in the disorder. Our results revealed differentially expressed proteins in pathways related to mitochondrial function, cell cycle control, DNA repair and neuritogenesis and their possible implication in key process of neurodevelopment, such as neuronal differentiation and axonal guidance signaling. Moreover, functional analysis of NSCs revealed alterations in mitochondrial oxygen consumption in schizophrenia-derived cells and a tendency of higher levels of intracellular reactive oxygen species (ROS). Hence, this study shows evidence that alterations in important cellular processes are present during neurodevelopment and could be involved with the establishment of schizophrenia, as well as the phenotypic traits observed in adult patients. Neural stem cells (NSCs) and neurons were derived from induced pluripotent stem cells (iPSCs) from schizophrenia patients and controls. Proteomic analyses were performed on the enriched mitochondrial and nuclear fractions of NSCs and neurons. Whole-cell proteomic analysis was also performed in neurons. Our results revealed alteration in proteins related to mitochondrial function, cell cycle control, among others. We also performed energy pathway analysis and reactive oxygen species (ROS) analysis of NSCs, which revealed alterations in mitochondrial oxygen consumption and a tendency of higher levels of intracellular ROS in schizophrenia-derived cells. [ABSTRACT FROM AUTHOR]

Brain abnormalities and congenital malformations have been linked to the circulating strain of Zika virus (ZIKV) in Brazil since 2016 during the microcephaly outbreak; however, the molecular mechanisms behind several of these alterations and differential viral molecular targets have not been fully elucidated. Here we explore the proteomic alterations induced by ZIKV by comparing the Brazilian (Br ZIKV) and the African (MR766) viral strains, in addition to comparing them to the molecular responses to the Dengue virus type 2 (DENV). Neural stem cells (NSCs) derived from induced pluripotent stem (iPSCs) were cultured both as monolayers and in suspension (resulting in neurospheres), which were then infected with ZIKV (Br ZIKV or ZIKV MR766) or DENV to assess alterations within neural cells. Large-scale proteomic analyses allowed the comparison not only between viral strains but also regarding the two- and three-dimensional cellular models of neural cells derived from iPSCs, and the effects on their interaction. Altered pathways and biological processes were observed related to cell death, cell cycle dysregulation, and neurogenesis. These results reinforce already published data and provide further information regarding the biological alterations induced by ZIKV and DENV in neural cells. [ABSTRACT FROM AUTHOR]

Duloxetine is a clinical drug that is primarily used for treatment of depression and pain, but it has side effects of addiction and tolerance. Cytochrome P450 (CYP) is its metabolic enzyme, and the drug's biofunction results from its neuro-protective effect in animal and cell models. We aimed to investigate the duloxetine-induced neural cytotoxicity effect and its performance in an N2a cell neurite outgrowth model. Cell death was assessed as cell viability using a Cell Count Kit-8 and further evaluated using bright-field images, propidium iodide (PI) and annexin V staining, colony-formation analysis, TUNEL staining of the cells, and biochemical testing. N2a cells were committed to differentiation by serum withdrawal and RA induction, and the neurite outgrowth was evaluated as the number of differentiated cells, longest neurite length, and average neurite length. Cell cycle analysis, PI and annexin V staining, mRNA expression, and biochemical testing were used to evaluate the drug effects on differentiation. The induction of neural cell death by duloxetine was not affected by classic cell death inhibitors but was promoted by the CYP inducer rifampicin. N2a cell neurite outgrowth was promoted by duloxetine via reduction of the CYP2D6 and MDA levels and induction of Bdnf protein levels. Duloxetine induces neural cell death through effects on CYP and promotes N2a cell neurite outgrowth by regulating CYP, Bdnf protein, and the intracellular lipid peroxidation level. [ABSTRACT FROM AUTHOR]

Stem cells have been long looked at as possible therapeutic vehicles in regenerative medicine largely due to their multi-lineage differentiation potential and paracrine actions. Therefore, development of new procedures for the differentiation of stem cells into different cell types holds great potential for opening new opportunities in regenerative medicine. In addition to various methods for inducing stem cell differentiation, the utilization of nanomaterials for differentiation of stem cells has recently received considerable attention and has become a potential tool for such purpose. Multiple lines of evidence revealed that nanomaterial-based scaffolds, inorganic nanoparticles (NPs), and biodegradable polymers have led to significant progress in regulation of stem cell differentiation. Several studies indicated that different NPs including selenium, gold, graphene quantum dots (QDs) and silica could be employed for the regulation of differentiation of stem cells such as human mesenchymal stem cells (hMSCs). In addition, magnetic core–shell NPs could be applied for the regulation of neural stem cell (NSC) differentiation. Taken together, these findings suggested that NPs are potential candidates which could be utilized for the differentiation of stem cells into various cell types such as neural cells. Herein, we summarized the application of NPs for differentiation of stem cells into various cells in particular neural cells. [ABSTRACT FROM AUTHOR]

Bone marrow mesenchymal stem cells (BMSCs) are multipotential differentiation cells which can differentiate into different cell types such as osteoblasts, chondrocytes, adipocytes, cardiomyocytes, hepatocytes, endothelial cells, and neuronal cells. Such multipotential differentiation makes them attractive for stem cell-based therapy aimed at treating previously incurable disorders. In the present work, we encapsulated BMSCs into a hydrogel with a three-dimensional (3D) network of nanofibers, formed from self-assembling of peptide amphiphile. The self-assembling of peptide amphiphile into hydrogel was triggered by mixing cell suspensions with dilute aqueous solutions of amphipathic peptide. Moreover, this hydrogel was designed to present cells the neurite-promoting laminin epitope IKVAV at nearly van der Waals density, which induced the successful differentiation of BMSCs into neural cells. [ABSTRACT FROM AUTHOR]

P19 embryonal carcinoma cells (EC-cells) provide a simple and robust culture system for studying neural development. Most protocols developed so far for directing neural differentiation of P19 cells depend on the use of culture medium supplemented with retinoic acid (RA) and serum, which has an undefined composition. Hence, such protocols are not suitable for many molecular studies. In this study, we achieved neural differentiation of P19 cells in a serum- and RA-free culture medium by employing the knockout serum replacement (KSR) supplement. In the KSR-containing medium, P19 cells underwent predominant differentiation into neural lineage and by day 12 of culture, neural cells were present in 100% of P19-derived embryoid bodies (EBs). This was consistently accompanied by the increased expression of various neural lineage-associated markers during the course of differentiation. P19-derived neural cells comprised of NES+ neural progenitors (~ 46%), TUBB3+ immature neurons (~ 6%), MAP2+ mature neurons (~ 2%), and GFAP+ astrocytes (~ 50%). A heterogeneous neuronal population consisting of glutamatergic, GABAergic, serotonergic, and dopaminergic neurons was generated. Taken together, our study shows that the KSR medium is suitable for the differentiation of P19 cells to neural lineage without requiring additional (serum and RA) supplements. This stem cell differentiation system could be utilized for gaining mechanistic insights into neural differentiation and for identifying potential neuroactive compounds. [ABSTRACT FROM AUTHOR]

Acetaminophen in a concentration of 5 mM increased the expression of JNK, HIF1A (hypoxiainduced factor), and CASP3, which indicated development of oxidative stress and apoptotic cell death. Acetaminophen in a concentration of 10 mM did not induce expression of HIF1A and CASP3, but reduced expression of chaperone HSP90, which attested to activation of a caspase-3-independent mechanism of cell death. The methods of preventing acetaminophen intoxication are discussed. [ABSTRACT FROM AUTHOR]

Many neural disorders are characterized by the loss of one or several types of neural cells. Human umbilical cord-derived mesenchymal cells (hUCMs) are capable of differentiating into neuron, astroglia-like and oligodendrocyte cell types. However, a reliable means of inducing the selective differentiation of hUCMs into neural cells in vitro has not yet been established. For induction of neural differentiation, hUCMs were seeded onto sterile glass slides and six various cocktails using a base medium (DMEM/LG) supplemented with 10 % FBS, retinoic acid (RA), dimethyl sulfoxide (DMSO), epidermal growth factor (EGF) and fibroblast growth factor (FGF) were used to compare their effect on neuronal, astrocyte and oligodandrocyte differentiation. The hUCMs were positive for mesenchymal markers, while they were negative for hematopoietic markers. Differentiation to adipogenic and osteogenic lineage was detected in these cells. Our data revealed that the cocktail consisting of DMEM/LG, FBS, RA, FGF, and EGF (DF/R/Fg/E group) induced hUCM cells to express the highest percentage of nestin, ß-tubulin III, neurofilament, and CNPase. The DF/Ds/Fg/E group led to the highest percentage of GFAP expression. While the expression levels of NF, GFAP, and CNPase were the lowest in the DF group. The least percentage of nestin and ß-tubulin III expression was observed in the DF/Ds group. We may conclude that FGF and EGF are important inducers for differentiation of hUCMs into neuron, astrocyte and oligodendrocyte. RA can induce hUCMs to differentiate into neuron and oligodendrocyte while for astrocyte differentiation DMSO had a pivotal role. [ABSTRACT FROM AUTHOR]

The aim of this study is to identify rat nasal septum respiratory mucosa-derived mesenchyme stem cells (RM-MSCs) and to compare its neural lineage differentiation capacity with bone marrow-derived mesenchyme stem cells (BM-MSCs) after a short period of neural induction culture in vitro. The cell morphology was observed with light microscopy; cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The characteristics of the cells were evaluated with flow cytometry, immunofluorescence, real-time quantitative PCR (RT-PCR), and Western blotting. The results showed that rat nasal respiratory mucosa contains RM-MSCs that exhibited similar proliferation rate as BM-MSCs in vitro. Both RT-PCR and Western blotting analyses demonstrated that RM-MSCs showed higher expression of neural lineage markers than BM-MSCs after a short period of neural induction culture, and secreted higher level of brain-derived neurotrophic factor. RM-MSCs were more amenable to differentiate into neural or glial cell after a short period of neural induction culture than BM-MSCs in vitro; and it could be considered as another optimal source of stem cells for cell-based therapy to neurological diseases. [ABSTRACT FROM AUTHOR]

Due to their tremendous antimicrobial properties, silver nanoparticles (AgNPs) have become incorporated into a number of consumer, industrial, and medical applications. However, AgNPs have also been shown to induce a strong cytotoxic response, brought on by an excess of cellular stress, which has severely limited the inclusion of AgNPs in nano-based biological applications, including drug delivery and bioimaging techniques. Previous investigations into magnetic field (MF) exposure have determined the potential of MFs to reduce the stress response in cellular systems; however, the ability of MF to protect cells from AgNPs has never been explored. As such, this study sought to identify if concurrent exposure to AgNPs and a 30-mT static MF could produce a diminishment of the cytotoxic and stress responses in a murine neural stem cell line (NE-4C). We discovered that the presence of MF provided a layer of protection from the negative AgNP effects, with a 15 % increase in viability noted up to a threshold concentration of 10 μg/mL. This partial recovery of AgNP-dependent cytotoxicity was found to correlate with increased ki67 expression and a substantial decrease in the NE-4C stress response including reactive oxygen species generation and NFκB and c-Jun expression. As neurological models are highly susceptible to stress, this study identified MF stimulation as a potential mechanism to counteract detrimental AgNP effects in neural cells, thereby demonstrating that a joint AgNP and MF system may be advantageous to progress neurological nano-based applications. [ABSTRACT FROM AUTHOR]

Organophosphorus (OP) compounds represent an important group of chemical warfare nerve agents that remains a significant and constant military and civilian threat. OP compounds are considered acting primarily via cholinergic pathways by binding irreversibly to acetylcholinesterase, an important regulator of the neurotransmitter acetylcholine. Many studies over the past years have suggested that other mechanisms of OP toxicity exist, which need to be unraveled by a comprehensive and systematic approach such as genome-wide gene expression analysis. Here we performed a microarray study in which cultured human neural cells were exposed to 0.1 or 10 μM of VX for 1 h. Global gene expression changes were analyzed 6, 24, and 72 h post exposure. Functional annotation and pathway analysis of the differentially expressed genes has revealed many genes, networks and canonical pathways that are related to nervous system development and function, or to neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, and Parkinson's disease. In particular, the neuregulin pathway impacted by VX exposure has important implications in many nervous system diseases including schizophrenia. These results provide useful information valuable in developing suitable antidotes for more effective prevention and treatment of, as well as in developing biomarkers for, VX-induced chronic neurotoxicity. [ABSTRACT FROM AUTHOR]

Foamy viruses (FVs) are classified to a subfamily of retrovirus presented in a wide range of hosts. None of FVs has been found to associate with any diseases in their native hosts. Such a unique biological character of FVs makes it suitable for the development of vectors for gene transfer. However, it is still controversial whether foamy virus vectors (FV vectors) can be applied to the central nervous system (CNS). In this review, we summarize the studies of FV vectors, which have been used for transduction of neural cells and other nondividing cells. We further discuss the potential mechanisms underlying the infection and propose that FVs can be used to develop transfer vectors for gene therapy in neurological disorders. [ABSTRACT FROM AUTHOR]

Several “low molecular weight” or “secretory” phospholipases A2 isoforms may be expressed in mammalian neural cells. Indeed, mRNAs for GIB, GIIA, GIIE, GIII, GV, GX, and GXII were detected in brain tissues despite different levels. However, only the presence of GIB, GIIA, and GV proteins has been clearly demonstrated in neural cells or in the nervous tissue. Although the roles of GIB and GV in the nervous tissue are still elusive, there is evidence to support the involvement of GIIA in physiological and pathological events, including neurotransmission, long-term potentiation, and neuritogenesis. The neurotoxic effects of an increase in GIIA may be envisaged under pathological conditions associated with the activation of astrocytes during inflammation or through activation of neurons and enzymes due to the stimulation of the NMDA glutamate receptor. In the past, elevation of GIIA expression in many acute and chronic neurological diseases is well known. Although each neurodegenerative disease has a separate etiology, many share similar neurochemical common processes, such as excitotoxicity, oxidative stress, and mitochondrial dysfunction, phenomena where GIIA play an important role. [ABSTRACT FROM AUTHOR]

The TUNEL method is used to quantify the proapoptotic effects of an NO donor, S-nitroso-N-acetylpenicillamine (SNAP), in NG108-15 cells. Unlike sodium nitroprusside used in previous studies, SNAP does not release cyanide along with NO, thus NO toxicity was determined without concurrent cyanide toxicity. The present study also determined if pretreatment with ANP could protect against NO-induced apoptosis in NG108-15 cells. Cell death at 24 h following SNAP treatment was associated with apoptotic DNA fragmentation. SNAP at 0.5, 0.75, 1.0, and 2.0 mM caused significant (P<0.05) increases in the percentage of TUNEL-labeled cells from a control of 0.90% to 6.19%, 6.36%, 7.25%, and 15.1%, respectively. Thus, SNAP caused concentration-dependent induction of apoptosis in NG108-15 cells. SNAP-induced apoptosis was confirmed by morphological changes and increased levels of polynucleosome-sized fragments of DNA assessed by capillary electrophoresis. Preincubation for 24 h with ANP at 0.01, 0.1, and 1.0 μM, before the SNAP, significantly (P<0.05) decreased the percentage of labeled cells from 7.25% to 5.10%, 4.36%, and 3.24% in the presence of SNAP (1 mM) and from 15.1% to 7.91%, 6.64%, and 5.60% in the presence of SNAP (2 mM), respectively, representing protection of 24.0%, 34.0%, and 57.0% against SNAP (1 mM) and 26.0%, 37.0%, and 50.9% against SNAP (2 mM). Thus, prior activation of a cGMP-mediated neuroprotective mechanism induced by ANP appears to counterbalance, at least partially, the proapoptotic effects of excess NO. This neuroprotective mechanism involving cGMP may be especially important in protecting against the development of neurodegenerative diseases in which excess NO is thought to contribute to neuronal apoptosis. [ABSTRACT FROM AUTHOR]

The possibility of differentiation of insulin-producing cells and neural and glial elements was demonstrated in the culture of bone marrow stromal cells. The perspectives of use of the bone marrow stromal cells in clinical medicine are considered. [ABSTRACT FROM AUTHOR]