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Photobiomodulation is a non-pharmacological tool widely used to reduce inflammation in many tissues. However, little is known about its effects on the inflammatory response in the aged brain. We conducted the study to examine anti-inflammatory effects of photobiomodulation in aging brains. We used aged rats (20 months old) with control (handled, laser off) or transcranial laser (660 nm wavelength, 100 mW power) treatments for 10 consecutive days and evaluated the level of inflammatory cytokines and chemokines, and the expression and activation of intracellular signaling proteins in the cerebral cortex and the hippocampus. Inflammatory analysis showed that aged rats submitted to transcranial laser treatment had increased levels of IL-1alpha and decreased levels of IL-5 in the cerebral cortex. In the hippocampus, the laser treatment increased the levels of IL-1alpha and decreased levels of IL-5, IL-18, and fractalkine. Regarding the intracellular signaling proteins, a reduction in the ERK and p38 expression and an increase in the STAT3 and ERK activation were observed in the cerebral cortex of aged rats from the laser group. In addition, the laser treatment increased the hippocampal expression of p70S6K, STAT3, and p38 of aged rats. Taken together, our data indicate that transcranial photobiomodulation can improve the inflammatory response and the activation of intracellular signaling proteins linked to vascular function and cell survival in the aged brain.

Epilepsy is the most common chronic neurologic disorder in the world, affecting 1-2% of the population. Besides, 30% of epilepsy patients are drug-resistant. Genomic mutations seem to play a key role in its etiology and knowledge of strong effect mutations in protein structures might improve prediction and the development of efficacious drugs to treat epilepsy. Several genetic association studies have been undertaken to examine the effect of a range of candidate genes for resistance. Although, few studies have explored the effect of the mutations into protein structure and biophysics in the epilepsy field. Much work remains to be done, but the plans made for exciting developments will hold therapeutic potential for patients with drug-resistance. In summary, we provide a critical review of the perspectives for the development of individualized medicine for epilepsy based on genetic polymorphisms/mutations in light of core elements such as transcriptomics, structural biology, disease model, pharmacogenomics and pharmacokinetics in a manner to improve the success of trial designs of antiepileptic drugs.

Recent evidences have shown the therapeutic potential of transcranial photobiomodulation on traumatic brain injury and Alzheimer's disease. Despite the promising benefits in the brain, little is known about the laser's effects in the absence of pathological conditions. We submitted young (4 months old) and aged (20 months old) rats to transcranial low-level laser and evaluated their exploratory activity and habituation in open field, anxiety in elevated plus maze, spatial memory in Barnes maze, and aversive memory in a step-down inhibitory avoidance task. Additionally, the levels of a panel of inflammatory cytokines and chemokines were quantified in two different brain regions: the cerebral cortex and the hippocampus. Young and aged rats submitted to transcranial laser exhibited better cognitive performance in Barnes maze than did control rats. Transcranial laser therapy decreased cortical levels of GM-CSF, IL-10, MCP-1, LIX, and TNFα in young rats and IL-5 in aged rats. High levels of IL-6, IL-10, and TNF-alpha were found in the cerebral cortex of aged rats submitted to transcranial laser. In the hippocampus, a decrease in IP-10 and fractalkine levels was observed in the aged rats from the laser group when compared to the aged rats from the control group. Our data indicate that transcranial photobiomodulation improves spatial learning and memory and alters the neuroinflammatory profile of young and aged rats' brains.

MeCP2 is an X-linked gene; its mutation causes Rett Syndrome (RTT), a severe neurodevelopmental disability that affects mainly girls. Acting as a transcription factor, the MeCP2 protein is able to regulate several hormone-related genes, such as the thyroid hormones (TH), which are known to play an important role in the development of the central nervous system (CNS). Although only a few studies have associated RTT and TH, TH deficit can lead to neurological deregulation by triggering functional deficiencies during adulthood. Here, we used human-induced pluripotent stem cell (iPSC) to generate MeCP2-knockout neuronal progenitor cells and adult neurons. Using this cellular model, we then investigated the expression of genes associated with TH homeostasis, such as the TH transporters (LAT1, LAT2, MCT8, MCT10, and OATP4A1) and deiodinases (DIO1, 2, and 3). Then, we treated the neural cells with THs and analyzed the expression of several genes related to neurodevelopment and functional maintenance. Our results showed that several TH-related genes, such as deiodinases, are altered in RTT samples when compared to WT cells. Moreover, the treatment of the neural cells with THs increased the amount of MAP2 and synapsin-1 expression in RTT cells. Our work provided evidences that TH homeostasis is compromised in RTT-derived neural cells, which could be an important factor to contribute to the imbalance in the neurodevelopmental phenotype presented in this syndrome and can lead us to better understand other neurodevelopmental diseases.

Physical activity has been considered an important non-medication intervention to preserve mnemonic processes during aging. However, how resistance exercise promotes such benefits remains unclear. A possible hypothesis is that brain-metabolic changes of regions responsible for memory consolidation is affected by muscular training. Therefore, we analyzed the memory, axiety and the metabolomic of aged male Wistar rats (19–20 months old in the 1st day of experiment) submitted to a 12-week resistance exercise protocol (EX, n = 11) or which remained without physical exercise (CTL, n = 13). Barnes maze, elevated plus maze and inhibitory avoidance tests were used to assess the animals’ behaviour. The metabolomic profile was identified by nuclear magnetic resonance spectrometry. EX group had better performance in the tests of learning and spatial memory in Barnes maze, and an increase of short and long-term aversive memories formation in inhibitory avoidance. In addition, the exercised animals showed a greater amount of metabolites, such as 4-aminobutyrate, acetate, butyrate, choline, fumarate, glycerol, glycine, histidine, hypoxanthine, isoleucine, leucine, lysine, niacinamide, phenylalanine, succinate, tyrosine, valine and a reduction of ascorbate and aspartate compared to the control animals. These data indicate that the improvement in learning and memory of aged rats submitted to resistance exercise program is associated by changes in the hippocampal metabolomic profile.

Current studies estimate that 1-3% of females with unexplained Intellectual Disability (ID) present de novo splice site, nonsense, frameshift, or missense mutations in the DDX3X protein (DEAD-Box Helicase 3 X-Linked). However, the cellular and molecular mechanisms by which DDX3X mutations impair brain development are not fully comprehended. Here, we show that the ID-linked missense mutation L556S renders DDX3X prone to aggregation. By using a combination of biophysical assays, in vitro and in vivo imaging approaches, we demonstrate that this mutant assemble solid-like condensates and amyloid-like fibrils. Although we observed greatly reduced expression of the mutant allele in the patient who exhibits skewed X inactivation, this appears to be enough to sequestrate healthy protein into solid-like ectopic granules, compromising cell function. Reduced viability of SH-SY5Y cells and impaired development of patient-derived brain organoids unfold with aberrant granules formation. Therefore, our data suggests ID-linked DDX3X L556S mutation as a disorder arising from protein misfolding and aggregation.

Liver transplantation from compatible donors has been the main therapy available for patients with irreversible hepatic injuries. Due to the increasing shortage of organs suitable for transplantation, tissue engineering technologies are important alternatives or surrogate approaches for the future of human organ transplantations. New bioengineering tools have been designed to produce decellularized organs (i.e. scaffolds) which could be recellularized with human cells. Specifically, there is an unmet need for developing reproducible protocols for inducing better cellular spreading in decellularized liver scaffolds. The aim of the present work was to investigate the possibility to improve liver scaffold recellularization by pre-coating decellularized tissue scaffolds with HepG2-conditioned medium (CM). Furthermore, we evaluated the capability of commercial human liver cells (HepG2) to adhere to several types of extracellular matrices (ECM) as well as CM components. Wistar rat livers were decellularized and analyzed by histology, scanning electron microscopy (SEM), immunohistochemistry and residual DNA-content analysis. Human induced pluripotent stem cells (hiPSCs)-derived mesenchymal cells (hiMSCs), and human commercial hepatic (HepG2) and endothelial (HAEC) cells were used for liver scaffold recellularization with or without CM pre-coating. Recellularization occurred for up to 5 weeks. Hepatic tissues and CM were analyzed by proteomic assays. We show that integrity and anatomical organization of the hepatic ECM were maintained after decellularization, and proteomic analysis suggested that pre-coating with CM enriched the decellularized liver ECM. Pre-coating with HepG2-CM highly improved liver recellularization and revealed the positive effects of liver ECM and CM components association.

Life experiences at early ages, such as physical activity in childhood and adolescence, can result in long-lasting brain effects able to reduce future risk of brain disorders and to enhance lifelong brain functions. However, how early physical exercise promotes these effects remains unclear. A possible hypothesis is that physical exercise increases the expression of neurotrophic factors and stimulates neuronal growth, resulting in a neural reserve to be used at later ages. Basing our study on this hypothesis, we evaluated the absolute number and morphology of neuronal cells, as well as the expression of growth, proliferation and survival proteins (BDNF, Akt, mTOR, p70S6K, ERK and CREB) in the cerebral cortex and hippocampal formation throughout of a sedentary period of rats who were physically active during youth. To do this, male Wistar rats were submitted to an aerobic exercise protocol from the 21st to the 60th postnatal days (P21–P60), and evaluated at 0 (P60), 30 (P90) and 60 (P120) days after the last exercise session. Results showed that juvenile exercise increased, and maintained elevated, the number of cortical and hippocampal neuronal cells and dendritic arborization, when evaluated at the above post-exercise ages. Hippocampal BDNF levels and cortical mTOR expression were found to be increased at P60, but were restored to control levels at P90 and P120. Overall, these findings indicate that, despite the short-term effects on growth and survival proteins, early exercise induces long-lasting morphological changes in cortical and hippocampal neurons even during a sedentary period of rats.

Several models of environmental enrichment and physical exercise have been used to explore the experience effects on brain functions and plasticity, mainly in adult animals. In order to examine the early influence of these stimuli on developing brain, the present study used calcium-binding protein parvalbumin as neuroplastic marker in the hippocampal formation of male Wistar rats subjected to environmental enrichment or physical exercise from postnatal days 21 to 60 (P21-P60). In our study, no significant difference in hippocampal expression and distribution of parvalbumin was found between enriched and control rats. However, a significant increase in parvalbumin protein expression as well as in the number of neurons stained with parvalbumin was observed in the hippocampal formation of rats submitted to daily treadmill exercise when compared to the control rats. The hippocampal region with the highest number of parvalbumin neurons in exercised rats was Cornus of Amon 2 e 3 (CA2/CA3). These findings indicate that developing brain may be differentially sensitive to environmental stimulation models. Specifically, our results show that hippocampal expression and distribution of parvalbumin in developing rats may be more influenced by exercise than by enriched environment. The mechanisms are not yet known.

Background Liver organoid technology holds great promises to be used in large-scale population-based drug screening and in future regenerative medicine strategies. Recently, some studies reported robust protocols for generating isogenic liver organoids using liver parenchymal and non-parenchymal cells derived from induced pluripotent stem cells (iPS) or using isogenic adult primary non-parenchymal cells. However, the use of whole iPS-derived cells could represent great challenges for a translational perspective. Methods Here, we evaluated the influence of isogenic versus heterogenic non-parenchymal cells, using iPS-derived or adult primary cell lines, in the liver organoid development. We tested four groups comprised of all different combinations of non-parenchymal cells for the liver functionality in vitro. Gene expression and protein secretion of important hepatic function markers were evaluated. Additionally, liver development-associated signaling pathways were tested. Finally, organoid label-free proteomic analysis and non-parenchymal cell secretome were performed in all groups at day 12. Results We show that liver organoids generated using primary mesenchymal stromal cells and iPS-derived endothelial cells expressed and produced significantly more albumin and showed increased expression of CYP1A1, CYP1A2, and TDO2 while presented reduced TGF-β and Wnt signaling activity. Proteomics analysis revealed that major shifts in protein expression induced by this specific combination of non-parenchymal cells are related to integrin profile and TGF-β/Wnt signaling activity. Conclusion Aiming the translation of this technology bench-to-bedside, this work highlights the role of important developmental pathways that are modulated by non-parenchymal cells enhancing the liver organoid maturation. Electronic supplementary material The online version of this article (10.1186/s13287-019-1367-x) contains supplementary material, which is available to authorized users.

Congenital Zika syndrome (CZS) causes early brain development impairment by affecting neural progenitor cells (NPCs). Here, we analyze NPCs from three pairs of dizygotic twins discordant for CZS. We compare by RNA-Seq the NPCs derived from CZS-affected and CZS-unaffected twins. Prior to Zika virus (ZIKV) infection the NPCs from CZS babies show a significantly different gene expression signature of mTOR and Wnt pathway regulators, key to a neurodevelopmental program. Following ZIKV in vitro infection, cells from affected individuals have significantly higher ZIKV replication and reduced cell growth. Whole-exome analysis in 18 affected CZS babies as compared to 5 unaffected twins and 609 controls excludes a monogenic model to explain resistance or increased susceptibility to CZS development. Overall, our results indicate that CZS is not a stochastic event and depends on NPC intrinsic susceptibility, possibly related to oligogenic and/or epigenetic mechanisms., Zika virus (ZIKV) infection can cause congenital Zika syndrome (CZS), but the underlying mechanisms are poorly understood. Here, the authors generate neural progenitor cells from dizygotic twins with a discordant phenotype regarding CZS and study their response to ZIKV infection.

Down syndrome (DS) is the most common cause of genetic intellectual disability, and the trisomy 21 is associated with more than 80 clinical traits, including higher risk for epilepsy. Several hypotheses have been put forward to explain the mechanisms underlying increased seizure susceptibility in DS: inherent structural brain abnormalities, abnormal cortical lamination, disruption of normal dendritic morphology, and underdeveloped synaptic profiles. A deficiency or loss of GABA inhibition is hypothesized to be one of the main alterations related to the epileptogenic process. Paradoxically, enhanced GABA inhibition has also been reported to promote seizures. One major functional abnormality observed in the brains of individuals and mouse models with DS appears to be an imbalance between excitatory and inhibitory neurotransmission, with excessive inhibitory brain function. This review discusses the GABAergic system in the human DS brain and the possible implication of the GABAergic network circuit in the epileptogenic process in individuals where the pathogenetic basis for epilepsy is unknown.

The assessment of neuronal number, spatial organization and connectivity is fundamental for a complete understanding of brain function. However, the evaluation of the three-dimensional (3D) brain cytoarchitecture at cellular resolution persists as a great challenge in the field of neuroscience. In this context, X-ray microtomography has shown to be a valuable non-destructive tool for imaging a broad range of samples, from dense materials to soft biological specimens, arisen as a new method for deciphering the cytoarchitecture and connectivity of the brain. In this work we present a method for imaging whole neurons in the brain, combining synchrotron-based X-ray microtomography with the Golgi-Cox mercury-based impregnation protocol. In contrast to optical 3D techniques, the approach shown here does neither require tissue slicing or clearing, and allows the investigation of several cells within a 3D region of the brain.

Congenital Zika syndrome (CZS) causes early brain development impairment by affecting neural progenitor cells (NPCs). Here, we analyze NPCs from three pairs of dizygotic twins discordant for CZS. We compare by RNA-Seq the NPCs derived from CZS-affected and CZS-unaffected twins. Prior to Zika virus (ZIKV) infection the NPCs from CZS babies show a significantly different gene expression signature of mTOR and Wnt pathway regulators, key to a neurodevelopmental program. Following ZIKV in vitro infection, cells from affected individuals have significantly higher ZIKV replication and reduced cell growth. Whole-exome analysis in 18 affected CZS babies as compared to 5 unaffected twins and 609 controls excludes a monogenic model to explain resistance or increased susceptibility to CZS development. Overall, our results indicate that CZS is not a stochastic event and depends on NPC intrinsic susceptibility, possibly related to oligogenic and/or epigenetic mechanisms.

Several methods have been used to study the neuropathogenesis of Down syndrome (DS), such as mouse aneuploidies, post mortem human brains, and in vitro cell culture of neural progenitor cells. More recently, induced pluripotent stem cell (iPSC) technology has offered new approaches in investigation, providing a valuable tool for studying specific cell types affected by DS, especially neurons and astrocytes. Here, we investigated the role of astrocytes in DS developmental disease and the impact of the astrocyte secretome in neuron mTOR signaling and synapse formation using iPSC derived from DS and wild-type (WT) subjects. We demonstrated for the first time that DS neurons derived from hiPSC recapitulate the hyperactivation of the Akt/mTOR axis observed in DS brains and that DS astrocytes may play a key role in this dysfunction. Our results bear out that 21 trisomy in astrocytes contributes to neuronal abnormalities in addition to cell autonomous dysfunctions caused by 21 trisomy in neurons. Further research in this direction will likely yield additional insights, thereby improving our understanding of DS and potentially facilitating the development of new therapeutic approaches.

New World primates play an important role in biomedical research. However, the literature still lacks information on many structural features of the brain in these species, particularly structures of the hippocampal formation that are related to long-term memory storage. This study was designed to provide information, for the first time, about the distribution and number of neurons expressing parvalbumin-immunoreactivity (PV-I) in the subregions of the hippocampal formation in Cebus apella, a New World primate species commonly used in biomedical research. Our results revealed that for several morphometric variables, PV-I cells differ significantly among the subregions CA1, CA2, CA3, and the hilus. Based upon our findings and those of other studies, we hypothesize that the proportional increase from monkeys to humans in PV-I cell density within CA1 is a factor contributing to the evolution of increased memory formation and storage. Am. J. Primatol. 77:449–461, 2015. © 2014 Wiley Periodicals, Inc.

Long-term structural and functional changes in the hippocampus have been identified as the primary physiopathological basis for temporal lobe epilepsy. These changes include reactive gliosis and granule cell axonal sprouting within the dentate gyrus. The intimate mechanisms of these changes are beginning to be revealed. Here, we show the possibility of using laser capture microdissection (LCM) to isolate the dentate granular cell layer of Wistar rats submitted to the pilocarpine model of epilepsy. Using two-dimensional gel electrophoresis (2-D PAGE) and mass spectrometry for laser-captured cells, we identified molecular events that could be altered as part of the epileptic pathogenic process. According to our results, eight proteins related to energy metabolism were differentially expressed between both the control and pilocarpine-treated animals. These results provide, for the first time, new molecular insights into the altered protein profile of the epileptogenic dentate gyrus and can contribute to a better understanding of the phenomena involved in the genesis and maintenance of the epileptic state.

The search for the source of beauty has exercised the speculation of philosophers and writers throughout the ages. The classical conception is that beauty consists of an arrangement of integral parts into a coherent whole, according to proportion, harmony, symmetry, and similar notions. The opposing view is that art is a fully subjective enterprise and our preferences are shaped by our values and experiences. To study beauty, neuroscience evokes the juxtaposition of concepts such as symmetry, geometry, proportion, judgment, affection, grotesque, erotic, sensitive with certain loci in the human brain. However, to explain and understand the aesthetic experiences at the network level, neuroscience have to incorporate the ambiguity in their research field. And with the continuous increasing of knowledge and comprehension of how beauty is perceived by the human brain, the world in its wholeness will be highly impacted, since we will start to live in pleasant societies.

Pre-clinical studies have supported the use of mesenchymal stem cells (MSC) to treat highly prevalent neurodegenerative diseases such as Parkinson’s disease (PD) but preliminary trials have reported controversial results. In a rat model of PD induced by MPTP neurotoxin, we first observed a significant bilateral preservation of dopaminergic neurons in the substantia nigra and prevention of motor deficits typically observed in PD such as hypokinesia, catalepsy, and bradykinesia, following intracerebral administration of human umbilical cord-derived MSC (UC-MSC) early after MPTP injury. However, surprisingly, administration of fibroblasts, mesenchymal cells without stem cell properties, as a xenotransplantation control was highly detrimental, causing significant neurodegeneration and motor dysfunction independently of MPTP. This observation prompted us to further investigate the consequences of transplanting a MSC preparation contaminated with fibroblasts, a plausible circumstance in cell therapy since both cell types display similar immunophenotype and can be manipulated in vitro under the same conditions. Here we show for the first time, using the same experimental model and protocol, that transplantation of UC-MSC induced potent neuroprotection in the brain resulting in clinical benefit. However, co-transplantation of UC-MSC with fibroblasts reverted therapeutic efficacy and caused opposite damaging effects, significantly exacerbating neurodegeneration and motor deficits in MPTP-exposed rats. Besides providing a rationale for testing UC-MSC transplantation in early phases of PD aiming at delaying disease progression, our pre-clinical study suggests that fibroblasts may be common cell contaminants affecting purity of MSC preparations and clinical outcome in stem cell therapy protocols, which might also explain discrepant clinical results. Electronic supplementary material The online version of this article (doi:10.1007/s12015-011-9256-4) contains supplementary material, which is available to authorized users.

Proechimys (Rodentia: Echimyidae) is a neotropical rodent of the Amazon region that has been successfully colonized in the laboratory and used for experimental medicine. Preliminary studies indicated that Proechimys (casiragua) rodents express an atypical resistance to developing a chronic epileptic condition in common models of temporal lobe epilepsy. Moreover, previous investigation of our laboratory described a remarkably different Proechimy's cytoarchitecture organization of the hippocampal CA2 subfield. In the present study, we investigated the intrinsic neuronal properties and morphological characteristics of the Proechimys's hippocampal pyramidal neurons of the CA1 and CA2 areas. A comparative approach was performed using neurons recorded in Wistar rats. A striking finding in Proechimys rodents was the presence of large pyramidal-like neurons throughout the stratum oriens from CA2 to CA1 area. In order to confirm such distinctive feature of the Proechimys's hippocampus, we performed Nissl staining and immunohistochemistry for neurofilament protein SM311. CA2 pyramidal neurons in the stratum pyramidale of Proechimys exhibited a significantly higher input resistance and lower time constant when compared to corresponding cell groups in the same area of the Wistar rat's. This newly identified population of pyramidal-shaped neurons in stratum oriens of Proechimys exhibited distinct electrophysiological and morphological properties. This included larger capacitance, lower input resistance, larger rheobase, long latency to first action potential and slower firing frequency. In addition, the apical dendrites of these neurons were oriented in parallel to apical dendrites of regular pyramidal neurons in stratum pyramidale. Moreover, these neurons were immunoreactive to SM311 as the majority of the neurons of the pyramidal layer. The functional role of these hippocampal neurons of the rodent Proechimys deserves further investigation.

Malnutrition during the earliest stages of life may result in innumerable brain problems. Moreover, this condition could increase the chances of developing neurological diseases, such as epilepsy. We analyzed the effects of early-life malnutrition on susceptibility to epileptic seizures induced by the pilocarpine model of epilepsy. Wistar rat pups were kept on a starvation regimen from day 1 to day 21 after birth. At day 60, 16 animals (8 = well-nourished; 8 = malnourished) were exposed to the pilocarpine experimental model of epilepsy. Age-matched well-nourished (n = 8) and malnourished (n = 8) rats were used as controls. Animals were video-monitored over 9 weeks. The following behavioral parameters were evaluated: first seizure threshold (acute period of the pilocarpine model); status epilepticus (SE) latency; first spontaneous seizure latency (silent period), and spontaneous seizure frequency during the chronic phase. The cell and mossy fiber sprouting (MFS) density were evaluated in the hippocampal formation. Our results showed that the malnourished animals required a lower pilocarpine dose in order to develop SE (200 mg/kg), lower latency to reach SE, less time for the first spontaneous seizure and higher seizure frequency, when compared to well-nourished pilocarpine rats. Histopathological findings revealed a significant cell density reduction in the CA1 region and intense MFS among the malnourished animals. Our data indicate that early malnutrition greatly influences susceptibility to seizures and behavioral manifestations in adult life. These findings suggest that malnutrition in infancy reduces the threshold for epilepsy and promotes alterations in the brain that persist into adult life.

Accumulating evidence indicates that the endocannabinoid system plays an essential role in the development and maturation of the central nervous system. Studies also have demonstrated that neural systems that regulate behavioral responses can be influenced by exercise during development. Exercise and endogenous cannabinoid activity have independently been shown to regulate brain plasticity, hence demonstrating a promising field of the endocannabinoid-exercise interaction. In order to investigate whether physical exercise during development would promote changes the brain endocannabinoid system, we investigated the cannabinoid receptor type 1 (CB1) expression in the brain of rats trained during the adolescent period. The results showed that an aerobic exercise program performed during adolescence significantly reduced the CB1 receptor expression in the striatum and hippocampal formation. These findings suggest an important link between the endocannabinoid system and physical training in adolescence.

Previous data of our laboratory have shown that the Amazonian rodents Proechimys do not present spontaneous seizures in different models of epilepsy, suggesting endogenous inhibitory mechanisms. Here, we describe a remarkably different Proechimy's cytoarchitecture organization of the hippocampal cornu Ammonis 2 (CA2) subfield. We identified a very distinctive Proechimy's CA2 sector exhibiting disorganized cell presentation of the pyramidal layer and atypical dispersion of the pyramidal-like cells to the stratum oriens, strongly contrasting to the densely packed CA2 cells in the Wistar rats. Studies showed that CA2 is the only cornu ammonis (CA) subfield resistant to the extensive pyramidal neural loss in mesial temporal lobe epilepsy (MTLE) associated to hippocampal sclerosis. Thus, in order to investigate this region, we used Nissl and Timm staining, stereological approach to count neurons and immunohistochemistry to neuronal nuclei (NeuN), parvalbumin (PV), calbindin (CB) and calretinin (CR). We did not notice statistically significant differences in the total number of neurons of the CA2 region between Proechimys and Wistar. However, Proechimys rodents presented higher CA2 volume than Wistar rats. Furthermore, no significant difference in the optical density of parvalbumin-immunoreactivity was found between subject groups. On the other hand, Proechimys presented significant higher density of calbindin and calretinin-immunoreactivity when compared to Wistar rats. In this context, this unique CA2 subfield seen in Proechimys opens up a new set of possibilities to explore the contribution of CA2 neurons in normal and pathological brain circuits.

Increased dosage of methyl-CpG-binding protein-2 (MeCP2) results in a dramatic neurodevelopmental phenotype with onset at birth. We generated induced pluripotent stem cells (iPSCs) from patients with the MECP2 duplication syndrome (MECP2dup), carrying different duplication sizes, to study the impact of increased MeCP2 dosage in human neurons. We show that cortical neurons derived from these different MECP2dup iPSC lines have increased synaptogenesis and dendritic complexity. In addition, using multi-electrodes arrays, we show that neuronal network synchronization was altered in MECP2dup-derived neurons. Given MeCP2 functions at the epigenetic level, we tested whether these alterations were reversible using a library of compounds with defined activity on epigenetic pathways. One histone deacetylase inhibitor, NCH-51, was validated as a potential clinical candidate. Interestingly, this compound has never been considered before as a therapeutic alternative for neurological disorders. Our model recapitulates early stages of the human MECP2 duplication syndrome and represents a promising cellular tool to facilitate therapeutic drug screening for severe neurodevelopmental disorders.

New World primates play an important role in biomedical research. However, the literature still lacks information on many structural features of the brain in these species, particularly structures of the hippocampal formation that are related to long-term memory storage. This study was designed to provide information, for the first time, about the distribution and number of neurons expressing parvalbumin-immunoreactivity (PV-I) in the subregions of the hippocampal formation in Cebus apella, a New World primate species commonly used in biomedical research. Our results revealed that for several morphometric variables, PV-I cells differ significantly among the subregions CA1, CA2, CA3, and the hilus. Based upon our findings and those of other studies, we hypothesize that the proportional increase from monkeys to humans in PV-I cell density within CA1 is a factor contributing to the evolution of increased memory formation and storage.

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder in which the MECP2 (methyl CpG-binding protein 2) gene is mutated. Recent studies showed that RTT-derived neurons have many cellular deficits when compared to control, such as: less synapses, lower dendritic arborization and reduced spine density. Interestingly, treatment of RTT-derived neurons with Insulin-like Growth Factor 1 (IGF1) could rescue some of these cellular phenotypes. Given the critical role of IGF1 during neurodevelopment, the present study used human induced pluripotent stem cells (iPSCs) from RTT and control individuals to investigate the gene expression profile of IGF1 and IGF1R on different developmental stages of differentiation. We found that the thyroid hormone receptor (TRalpha 3) has a differential expression profile. Thyroid hormone is critical for normal brain development. Our results showed that there is a possible link between IGF1/IGF1R and the TRalpha 3 and that over expression of IGF1R in RTT cells may be the cause of neurites improvement in neural RTT-derived neurons.

There is a great deal of evidence showing the capacity of physical exercise to enhance cognitive function, reduce anxiety and depression, and protect the brain against neurodegenerative disorders. Although the effects of exercise are well documented in the mature brain, the influence of exercise in the developing brain has been poorly explored. Therefore, we investigated the morphological and functional hippocampal changes in adult rats submitted to daily treadmill exercise during the adolescent period. Male Wistar rats aged 21 postnatal days old (P21) were divided into two groups: exercise and control. Animals in the exercise group were submitted to daily exercise on the treadmill between P21 and P60. Running time and speed gradually increased over this period, reaching a maximum of 18 m/min for 60 min. After the aerobic exercise program (P60), histological and behavioral (water maze) analyses were performed. The results show that early-life exercise increased mossy fibers density and hippocampal expression of brain-derived neurotrophic factor and its receptor tropomyosin-related kinase B, improved spatial learning and memory, and enhanced capacity to evoke spatial memories in later stages (when measured at P96). It is important to point out that while physical exercise induces hippocampal plasticity, degenerative effects could appear in undue conditions of physical or psychological stress. In this regard, we also showed that the exercise protocol used here did not induce inflammatory response and degenerating neurons in the hippocampal formation of developing rats. Our findings demonstrate that physical exercise during postnatal development results in positive changes for the hippocampal formation, both in structure and function.

Universidade Federal de S?o Paulo. Departamento de Neurologia e Neurocirurgia. S?o Paulo, SP, Brazil / Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro Nacional de Primatas. Bel?m, PA, Brasil. Universidade Federal de S?o Paulo. Departamento de Neurologia e Neurocirurgia. S?o Paulo, SP, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro Nacional de Primatas. Bel?m, PA, Brasil. Hospital Israelita Albert Einstein. Instituto do C?rebro. S?o Paulo, SP, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro Nacional de Primatas. Bel?m, PA, Brasil. Universidade de Bras?lia. Bras?lia, DF, Brazil. Universidade Federal de S?o Paulo. Departamento de Neurologia e Neurocirurgia. S?o Paulo, SP, Brazil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro Nacional de Primatas. Bel?m, PA, Brasil. Universidade Federal de S?o Paulo. Departamento de Neurologia e Neurocirurgia. S?o Paulo, SP, Brazil. Animal experimentation contributes significantly to the progression of science. Nonhuman primates play a particularly important role in biomedical research not only because of their anatomical, physiological, biochemical, and behavioral similarities with humans but also because of their close phylogenetic affinities. In order to investigate the use of New World primates (NWP) in biomedical research over the last four decades (1966?2005), we performed a quantitative study of the literature listed in bibliographic databases from the Health Sciences. The survey was performed for each genus of NWP that has been bred in the National Center of Primates in Brazil. The number of articles published was determined for each genus and sorted according to the country from which the studies originated and the general scientific field. The data obtained suggests that Brazil is a leader in generating knowledge with NWP models for translational medicine.

Proechimys, a rodent living in the Amazon region, has shown resistance to developing chronic epilepsy when submitted to different experimental models. Recently, many studies have attributed a potent anticonvulsant action to cannabinoid receptor CB1. This study investigated the distribution and expression of the CB1 receptor in the hippocampal formation of Proechimys using immunohistochemistry and Western blotting techniques. Results were compared with values obtained from adult Wistar rats. The immunoreactivity for CB1 was evident throughout the Ammon's horn and in the hilar region of both animal species. However, the distribution of these receptors was higher in the stratum lucidum of CA3 and in the hilar region of Proechimys. In addition, higher expression of CB1 receptors was observed in the Proechimys hippocampus. These data could explain, at least partially, the natural resistance of this animal species to developing spontaneous seizures following epileptogenic precipitating events.

International audience; Point cloud models are a common shape representation for several reasons. Three-dimensional scanning devices are widely used nowadays and points are an attractive primitive for rendering complex geometry. Nevertheless, there is not much literature on collision detection for point cloud models. This paper presents a novel collision detection algorithm for large point cloud models using voxels, octrees and bounding spheres hierarchies (BSH). The scene graph is divided in voxels. The objects of each voxel are organized intoan octree. Due to the high number of points in the scene, each non-empty cell of the octree is organized in a bounding sphere hierarchy, based on an R-tree hierarchy like structure. The BSH hierarchies are used to group neighboring points and filter out very quickly parts of objects that do not interact with other models. Points derived from laser scanned data typically are not segmented and can have arbitrary spatial resolution thus introducing computational and modeling issues. We address these issues and our results show that the proposed collision detection algorithm effectively finds intersections between point cloud models since it is able to reduce the number of bounding volume checks and updates

O Transtorno do Espectro Autista (TEA) caracteriza-se como um complexo distúrbio do neurodesenvolvimento de início precoce. Características comuns como isolamento social, interesses restritos, comportamentos estereotipados e repetitivos estão sempre presentes. Estudos genômicos em larga escala levaram a identificação de um grande número de genes associados ao TEA, e consequentemente, novos quadros clínicos e síndromes têm sido caracterizados. Dentre as síndromes mais recentemente associadas ao TEA, gostaríamos de destacar a síndrome de Phelan-McDermid (PMS), e a Hipotonia infantil com retardo psicomotor e características faciais 3 (IHPRF3). Selecionamos como primeira abordagem deste estudo a caracterização genótipo-fenótipo de PMS (ou síndrome da deleção do 22q13.3), visto que os dados existentes neste sentido ainda são conflitantes. A PMS é ocasionada em geral por deleções de diferentes tamanhos que envolvem o gene SHANK3, e os dados atuais da literatura sugerem que a deleção de SHANK3 causa a maioria dos sintomas neurológicos descritos na síndrome. No entanto, ainda não é totalmente resolutivo qual a implicação do tamanho de deleções em SHANK3 relacionados a variabilidade clínica, e quais outros genes adjacentes contribuem para o fenótipo observado em PMS. Sendo assim, no presente estudo descrevemos pela primeira vez uma casuística brasileira de pacientes com PMS, e os nossos resultados contribuíram para uma melhor caracterização molecular e clínica da síndrome, visto que: estimamos o tamanho mínimo de deleção para o desenvolvimento de comorbidades como problema renal; identificamos um indivíduo atípico com PMS que não apresenta deficiência intelectual; e estimamos a frequência de indivíduos com PMS em uma coorte de TEA e outra de DI. Com segunda abordagem, tendo em vista a falta de compreensão dos mecanismos patofisiológicos da síndrome IHPRF3, optamos por realizar a caracterização de neurônios de indivíduos com essa síndrome (IHPRF3) utilizando a técnica de reprogramação celular. A IHPRF3 é ocasionada por mutações bi-alélicas de perda de função no gene TBCK localizado em 4q24 e se caracteriza clinicamente por hipotonia, deficiência intelectual grave e autismo. Há também evidências de que ocorra neurodegeneração do sistema nervoso central e periférico em alguns casos, a qual pode iniciar na infância, justificando então a importância da caracterização de células neuronais de indivíduos afetados. Os nossos resultados mostraram que os neurônios de afetados derivados de iPSC apresentam alterações na morfologia e expressão de genes relacionados ao neurodesenvolvimento, que corroboram a influência de TBCK no desenvolvimento cortical. Apesar da grande heterogeneidade genética observada entre os casos de TEA, os dados de anotação funcional indicam que uma parcela significativa dos genes relacionados ao autismo converge em vias moleculares e biológicas específicas. Delimitar quais os efeitos fenotípicos ocasionados por diferentes mutações em diferentes genes que podem auxiliar na busca por mecanismos moleculares comuns entre os quadros de autismo. Desta maneira, realizar um delineamento clínico e caracterização funcional destas síndromes auxilia na compreensão do TEA como um todo Autism Spectrum disorders (ASD) are complex neurodevelopmental early-onset disorders presenting with abnormal social behavior and communication, repetitive behavior and restricted interests. Recent advances in large-scale genomic sequencing have identified hundreds of genes associated with ASD, enabling characterization of new syndromes and clinical features. Among the most recent syndromes associated with ASD, here we focus on Phelan McDermid syndrome (PMS), and Hypotonia, infantile, with psychomotor retardation and characteristic facies 3 (IHPRF3). We performed a genotype-phenotype correlation study for PMS (or 22q13.3 deletion syndrome), since the existing literature in this regard is still conflicting. PMS is caused by deletions involving the SHANK3, which are responsible for most of the neurological symptoms in this syndrome. However, how deletion size and whether affected nearby genes impact the PMS phenotype remains to be elucidated. In the present study, we described for the first time a brazilian cohort of patients with PMS and contributed to the molecular and clinical characterization of the syndrome. We estimated the minimum deletion size for the development of comorbidities; we identified an atypical PMS case lacking intellectual disability; and finally, we estimated the frequency of individuals with PMS in an independent? cohort comprising ASD and ID cases. Regarding IHPRF3, in view of the lack of understanding of its pathophysiological mechanisms, we attempted to model IHPRF3 in vitro by characterizing the cellular phenotypes of patients\' cortical neurons in vitro. The IHPRF3 was caused by bi-allelic loss-of-function mutations in the TBCK gene, and is clinically characterized by hypotonia, severe intellectual disability and ASD. There is evidence that neurodegeneration of the central and peripheral nervous system occurs in some cases, which may begin in childhood, thus justifying the importance of characterizing neural cells from patients. IHPRF3 neurons showed changes in morphology and expression of genes related to neurodevelopment, confirming the importance of TBCK for cortical development. Despite the great genetic heterogeneity observed among ASD cases, a significant proportion ASD-related gene have been shown to converge into specific molecular and biological pathways, and delineating the phenotypic effects caused by mutations in different genes contributes to the search for such altered pathways common to various ASD cases. Therefore, the clinical, molecular and functional characterization of ASD-associated syndromes such as PMS and IHPRF3 aids in elucidating the pathophysiology of ASD as a whole

Meduloblastoma é o câncer do Sistema Nervoso Central mais comum em crianças entre 0 e 4 anos. Ele é originado de células precursoras neuronais, que falharam em se diferenciar e continuaram a se proliferar. A proteína SAM68 está desregulada em várias linhagens de células de cânceres humanos e é uma proteína que pode estar envolvida em uma ampla gama de vias de sinalização importantes, incluindo metabolismo de RNA, regulação do ciclo celular, apoptose, regulação de splicing e transdução de sinal. Em células-tronco neurais (NSC), níveis elevados de SAM68 levam a uma redução importante na proliferação celular. Contudo, na maioria dos cânceres estudados até o momento, a SAM68 está envolvida com progressão tumoral. Com este trabalho, buscou-se entender o envolvimento de SAM68 na proliferação e morte de células de meduloblastoma. Por meio da análise de expressão transcricional e proteica, do silenciamento de SAM68, análise de apoptose por citometria de fluxo e análise de proliferação por índice mitótico e incorporação de EdU, observou-se que, em linhagens de meduloblastoma, a SAM68 está envolvida com proliferação, mas não com apoptose. Seu funcionamento em meduloblastoma é similar aos resultados obtidos com NCS do que com outros tipos de câncer, visto que o silenciamento dessa proteína favorece a proliferação das células de meduloblastoma. Em vista dos resultados aparentemente conflitantes, tendo um papel mais semelhante a um supressor tumoral, porém sendo altamente expressa em meduloblasoma, sugeriram-se algumas hipóteses, que foram apenas inicialmente testadas neste trabalho, mas precisam ser aprofundadas em trabalhos futuros SAM68 is considered a prototype of STAR proteins (Signal Transducers and Activators of RNA protein), that are involved in the signal translation and RNA activation. In cancer, the intracellular levels of Sam68 are crucial to the progression of the disease. Recent observations indicate Sam68 with both pro-oncogenic and tumor suppressor activities, depending on the type of cell. Here, we analyzed SAM68 expression by real time PCR and western blot, proliferation of cell with and without SAM68 by mitotic index and incorporation of EdU and cell death by flux cytometry to define the relevance of the presence of SAM68 to cell proliferation and death. We found that proliferation of medulloblastoma cell lines are affected for absent SAM68, but not apoptosis. Because the contrast of an action similar to a tumor suppressor and a high expression level, we hypothesized that the increase of SAM68 levels is important during the neuronal development, regulating splicing variants. Our results allied to some literature data corroborate this hypothesis