Neural networks are responsible for processing sensory stimuli and driving the synaptic activity required for brain function and behavior. This computational capacity is expensive and requires a steady supply of energy and building blocks to operate. Importantly, the neural networks are composed of different cell populations, whose metabolic profiles differ between each other, thus endowing them with different metabolic capacities, such as, for example, the ability to synthesize specific metabolic precursors or variable proficiency to manage their metabolic waste. These marked differences likely prompted the emergence of diverse intercellular metabolic interactions, in which the shuttling and cycling of specific metabolites between brain cells allows the separation of workload and efficient control of energy demand and supply within the central nervous system. Nevertheless, our knowledge about brain bioenergetics and the specific metabolic adaptations of neural cells still warrants further studies. In this review, originated from the Fourth International Society for Neurochemistry (ISN) and Journal of Neurochemistry (JNC) Flagship School held in Schmerlenbach, Germany (2022), we describe and discuss the specific metabolic profiles of brain cells, the intercellular metabolic exchanges between these cells, and how these bioenergetic activities shape synaptic function and behavior. Furthermore, we discuss the potential role of faulty brain metabolic activity in the etiology and progression of Alzheimer's disease, Parkinson disease, and Amyotrophic lateral sclerosis. We foresee that a deeper understanding of neural networks metabolism will provide crucial insights into how higher-order brain functions emerge and reveal the roots of neuropathological conditions whose hallmarks include impaired brain metabolic function.

• MeSH
• Energy Metabolism * physiology   MeSH
• Humans MeSH
• Metabolic Networks and Pathways * physiology   MeSH
• Brain * metabolism   MeSH
• Nerve Net * metabolism   MeSH
• Neurons * metabolism   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

BACKGROUND: The hippocampal representation of space, formed by the collective activity of populations of place cells, is considered as a substrate of spatial memory. Alzheimer's disease (AD), a widespread severe neurodegenerative condition of multifactorial origin, typically exhibits spatial memory deficits among its early clinical signs before more severe cognitive impacts develop. OBJECTIVE: To investigate mechanisms of spatial memory impairment in a double transgenic rat model of AD. METHODS: In this study, we utilized 9-12-month-old double-transgenic TgF344-AD rats and age-matched controls to analyze the spatial coding properties of CA1 place cells. We characterized the spatial memory representation, assessed cells' spatial information content and direction-specific activity, and compared their population coding in familiar and novel conditions. RESULTS: Our findings revealed that TgF344-AD animals exhibited lower precision in coding, as evidenced by reduced spatial information and larger receptive zones. This impairment was evident in maps representing novel environments. While controls instantly encoded directional context during their initial exposure to a novel environment, transgenics struggled to incorporate this information into the newly developed hippocampal spatial representation. This resulted in impairment in orthogonalization of stored activity patterns, an important feature directly related to episodic memory encoding capacity. CONCLUSIONS: Overall, the results shed light on the nature of impairment at both the single-cell and population levels in the transgenic AD model. In addition to the observed spatial coding inaccuracy, the findings reveal a significantly impaired ability to adaptively modify and refine newly stored hippocampal memory patterns.

• MeSH
• Alzheimer Disease * physiopathology   MeSH
• Amyloid beta-Protein Precursor genetics   MeSH
• CA1 Region, Hippocampal physiopathology   MeSH
• Hippocampus physiopathology   MeSH
• Rats MeSH
• Humans MeSH
• Disease Models, Animal * MeSH
• Memory Disorders etiology   physiopathology   MeSH
• Rats, Inbred F344 MeSH
• Rats, Transgenic * MeSH
• Spatial Memory physiology   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Humans MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

Hledání optimálního nastavení podmínek chemické analýzy je zpravidla zdlouhavý proces. Tento článek k tomuto účelu navrhuje využití neuronových sítí, zejména ve vztahu k určení optimální podmínek pro analýzu zkoumaných látek s využitím technologie LC/MS/MS a ESI ionizací, a to na základě znalosti jejich základních vlastností, označených jako univerzální deskriptory. Práce se soustředí na nalezení takových podmínek analýzy, kdy dochází k maximalizaci signálu iontu prekurzoru. Práce se zabývá zejména otázkou, zda lze výsledky zjištěné na jednom typu analytu použít k neurální interpolační predikci optimálních podmínek analytů podobných.

The search for the optimal instrumental settings of conditions in chemical analysis is typically a lengthy process. This article proposes the use of neural networks for this purpose, particularly in relation to determining the optimal conditions for the analysis of substances under study using LC/MS/MS and ESI technologies, based on the knowledge of their fundamental properties, referred to as universal descriptors. The work focuses on finding such analysis conditions that maximize the precursor ion signal. The paper specifically addresses the question of whether the results obtained from one type of analyte can be used for neural-interpolated prediction of optimal conditions for similar analytes.

• MeSH
• Chemical Warfare Agents chemistry   MeSH
• Chemistry Techniques, Analytical methods   MeSH
• Chromatography, Liquid methods   MeSH
• Spectrometry, Mass, Electrospray Ionization methods   MeSH
• Mass Spectrometry methods   MeSH
• Humans MeSH
• Neural Networks, Computer MeSH
• Organophosphates * chemistry   analysis   MeSH
• Check Tag
• Humans MeSH

The search for the optimal instrumental settings of conditions in chemical analysis is typically a lengthy process. This article proposes the use of neural networks for this purpose, particularly in relation to determining the optimal conditions for the analysis of substances under study using LC/MS/MS and ESI technologies, based on the knowledge of their fundamental properties, referred to as universal descriptors. The work focuses on finding such analysis conditions that maximize the precursor ion signal. The paper specifically addresses the question of whether the results obtained from one type of analyte can be used for neural-interpolated prediction of optimal conditions for similar analytes.

• MeSH
• Chemical Warfare Agents analysis   chemistry   MeSH
• Chemistry Techniques, Analytical methods   MeSH
• Chromatography, Liquid methods   MeSH
• Spectrometry, Mass, Electrospray Ionization methods   MeSH
• Mass Spectrometry methods   MeSH
• Humans MeSH
• Neural Networks, Computer MeSH
• Organophosphates * analysis   chemistry   MeSH
• Check Tag
• Humans MeSH

Close relationship between melanocytes and neural cells is accepted to reflect their common derivation from the neural crest and tumors combining both elements. We present a series of 10 patients with giant congenital melanocytic nevi (CMN) in which a secondary proliferation (11 lesions) with schwannian and/or perineuriomatous differentiation developed in the course of the disease. The age of the patients (4 male and 6 female) at the time of surgery and histological assessment varied from 3 months to 57 years. Histopathologically, the following subgroups were delineated: (1) nodular/tumoriform "neurotization" in CMN, (2) diffuse neurofibroma-like proliferation within CMN, (3) plexiform neurofibroma-like proliferation within CMN, and (4) diffuse perineuriomatous (hybrid schwannomatous-perineuriomatous) differentiation in CMN. We review the pertinent literature, including the role of recently identified Schwann cell precursors which are believed to represent the nerve-associated state of neural crest-like cells that persists into later developmental stages.

• MeSH
• Cell Differentiation * MeSH
• Child MeSH
• Adult MeSH
• Infant MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Skin Neoplasms * pathology   congenital   MeSH
• Nevus, Pigmented * pathology   congenital   MeSH
• Child, Preschool MeSH
• Schwann Cells * pathology   MeSH
• Check Tag
• Child MeSH
• Adult MeSH
• Infant MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Male MeSH
• Child, Preschool MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Effective treatment of patients with autism spectrum disorder (ASD) is still absent so far. Taurine exhibits therapeutic effects towards the autism-like behaviour in ASD model animals. Here, we determined the mechanism of taurine effect on hippocampal neurogenesis in genetically inbred BTBR T+ tf/J (BTBR) mice, a proposed model of ASD. In this ASD mouse model, we explored the effect of oral taurine supplementation on ASD-like behaviours in an open field test, elevated plus maze, marble burying test, self-grooming test, and three-chamber test. The mice were divided into four groups of normal controls (WT) and models (BTBR), who did or did not receive 6-week taurine supplementation in water (WT, WT+ Taurine, BTBR, and BTBR+Taurine). Neurogenesis-related effects were determined by Ki67 immunofluorescence staining. Western blot analysis was performed to detect the expression of phosphatase and tensin homologue deleted from chromosome 10 (PTEN)/mTOR/AKT pathway-associated proteins. Our results showed that taurine improved the autism-like behaviour, increased the proliferation of hippocampal cells, promoted PTEN expression, and reduced phosphorylation of mTOR and AKT in hippocampal tissue of the BTBR mice. In conclusion, taurine reduced the autism-like behaviour in partially inherited autism model mice, which may be associa-ted with improving the defective neural precursor cell proliferation and enhancing the PTEN-associated pathway in hippocampal tissue.

• MeSH
• Autistic Disorder * metabolism   drug therapy   MeSH
• Behavior, Animal drug effects   MeSH
• PTEN Phosphohydrolase * metabolism   MeSH
• Hippocampus * metabolism   drug effects   MeSH
• Disease Models, Animal MeSH
• Mice MeSH
• Neurogenesis * drug effects   MeSH
• Autism Spectrum Disorder metabolism   drug therapy   MeSH
• Cell Proliferation drug effects   MeSH
• Proto-Oncogene Proteins c-akt * metabolism   MeSH
• Signal Transduction * drug effects   MeSH
• Taurine * pharmacology   MeSH
• TOR Serine-Threonine Kinases * metabolism   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

Alpers' syndrome is an early-onset neurodegenerative disorder usually caused by biallelic pathogenic variants in the gene encoding the catalytic subunit of polymerase-gamma (POLG), which is essential for mitochondrial DNA (mtDNA) replication. The disease is progressive, incurable, and inevitably it leads to death from drug-resistant status epilepticus. The neurological features of Alpers' syndrome are intractable epilepsy and developmental regression, with no effective treatment; the underlying mechanisms are still elusive, partially due to lack of good experimental models. Here, we generated the patient derived induced pluripotent stem cells (iPSCs) from one Alpers' patient carrying the compound heterozygous mutations of A467T (c.1399G>A) and P589L (c.1766C>T), and further differentiated them into cortical organoids and neural stem cells (NSCs) for mechanistic studies of neural dysfunction in Alpers' syndrome. Patient cortical organoids exhibited a phenotype that faithfully replicated the molecular changes found in patient postmortem brain tissue, as evidenced by cortical neuronal loss and depletion of mtDNA and complex I (CI). Patient NSCs showed mitochondrial dysfunction leading to ROS overproduction and downregulation of the NADH pathway. More importantly, the NAD+ precursor nicotinamide riboside (NR) significantly ameliorated mitochondrial defects in patient brain organoids. Our findings demonstrate that the iPSC model and brain organoids are good in vitro models of Alpers' disease; this first-in-its-kind stem cell platform for Alpers' syndrome enables therapeutic exploration and has identified NR as a viable drug candidate for Alpers' disease and, potentially, other mitochondrial diseases with similar causes.

• MeSH
• DNA Polymerase gamma MeSH
• Induced Pluripotent Stem Cells * MeSH
• Humans MeSH
• DNA, Mitochondrial genetics   MeSH
• Mitochondrial Diseases * MeSH
• Mutation MeSH
• NAD genetics   MeSH
• Niacinamide analogs & derivatives   MeSH
• Pyridinium Compounds * MeSH
• Diffuse Cerebral Sclerosis of Schilder * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

One of the challenges in clinical translation of cell-replacement therapies is the definition of optimal cell generation and storage/recovery protocols which would permit a rapid preparation of cell-treatment products for patient administration. Besides, the availability of injection devices that are simple to use is critical for potential future dissemination of any spinally targeted cell-replacement therapy into general medical practice. Here, we compared the engraftment properties of established human-induced pluripotent stem cells (hiPSCs)-derived neural precursor cell (NPCs) line once cells were harvested fresh from the cell culture or previously frozen and then grafted into striata or spinal cord of the immunodeficient rat. A newly developed human spinal injection device equipped with a spinal cord pulsation-cancelation magnetic needle was also tested for its safety in an adult immunosuppressed pig. Previously frozen NPCs showed similar post-grafting survival and differentiation profile as was seen for freshly harvested cells. Testing of human injection device showed acceptable safety with no detectable surgical procedure or spinal NPCs injection-related side effects.

• MeSH
• Cell Differentiation physiology   MeSH
• Adult MeSH
• Genetic Vectors genetics   MeSH
• Induced Pluripotent Stem Cells * physiology   transplantation   MeSH
• Rats MeSH
• Humans MeSH
• Spinal Cord MeSH
• Brain MeSH
• Neural Stem Cells * physiology   transplantation   MeSH
• Specimen Handling methods   MeSH
• Tissue and Organ Harvesting methods   MeSH
• Swine MeSH
• Cellular Reprogramming * genetics   physiology   MeSH
• Graft Survival physiology   MeSH
• Injections, Spinal * adverse effects   instrumentation   methods   MeSH
• Stem Cell Transplantation * adverse effects   instrumentation   methods   MeSH
• Sendai virus MeSH
• Treatment Outcome MeSH
• Animals MeSH
• Check Tag
• Adult MeSH
• Rats MeSH
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

The critical requirements in developing clinical-grade human-induced pluripotent stem cells-derived neural precursors (hiPSCs-NPCs) are defined by expandability, genetic stability, predictable in vivo post-grafting differentiation, and acceptable safety profile. Here, we report on the use of manual-selection protocol for generating expandable and stable human NPCs from induced pluripotent stem cells. The hiPSCs were generated by the reprogramming of peripheral blood mononuclear cells with Sendai-virus (SeV) vector encoding Yamanaka factors. After induction of neural rosettes, morphologically defined NPC colonies were manually harvested, re-plated, and expanded for up to 20 passages. Established NPCs showed normal karyotype, expression of typical NPCs markers at the proliferative stage, and ability to generate functional, calcium oscillating GABAergic or glutamatergic neurons after in vitro differentiation. Grafted NPCs into the striatum or spinal cord of immunodeficient rats showed progressive maturation and expression of early and late human-specific neuronal and glial markers at 2 or 6 months post-grafting. No tumor formation was seen in NPCs-grafted brain or spinal cord samples. These data demonstrate the effective use of in vitro manual-selection protocol to generate safe and expandable NPCs from hiPSCs cells. This protocol has the potential to be used to generate GMP (Good Manufacturing Practice)-grade NPCs from hiPSCs for future clinical use.

• MeSH
• Cell Differentiation MeSH
• Induced Pluripotent Stem Cells * MeSH
• Rats MeSH
• Leukocytes, Mononuclear MeSH
• Humans MeSH
• Neural Stem Cells * MeSH
• Neurons metabolism   MeSH
• Sendai virus genetics   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

Heterozygous pathogenic variants in POLR1A, which encodes the largest subunit of RNA Polymerase I, were previously identified as the cause of acrofacial dysostosis, Cincinnati-type. The predominant phenotypes observed in the cohort of 3 individuals were craniofacial anomalies reminiscent of Treacher Collins syndrome. We subsequently identified 17 additional individuals with 12 unique heterozygous variants in POLR1A and observed numerous additional phenotypes including neurodevelopmental abnormalities and structural cardiac defects, in combination with highly prevalent craniofacial anomalies and variable limb defects. To understand the pathogenesis of this pleiotropy, we modeled an allelic series of POLR1A variants in vitro and in vivo. In vitro assessments demonstrate variable effects of individual pathogenic variants on ribosomal RNA synthesis and nucleolar morphology, which supports the possibility of variant-specific phenotypic effects in affected individuals. To further explore variant-specific effects in vivo, we used CRISPR-Cas9 gene editing to recapitulate two human variants in mice. Additionally, spatiotemporal requirements for Polr1a in developmental lineages contributing to congenital anomalies in affected individuals were examined via conditional mutagenesis in neural crest cells (face and heart), the second heart field (cardiac outflow tract and right ventricle), and forebrain precursors in mice. Consistent with its ubiquitous role in the essential function of ribosome biogenesis, we observed that loss of Polr1a in any of these lineages causes cell-autonomous apoptosis resulting in embryonic malformations. Altogether, our work greatly expands the phenotype of human POLR1A-related disorders and demonstrates variant-specific effects that provide insights into the underlying pathogenesis of ribosomopathies.

• MeSH
• Apoptosis MeSH
• Neural Crest pathology   MeSH
• Phenotype MeSH
• Craniofacial Abnormalities * genetics   pathology   MeSH
• Humans MeSH
• Mandibulofacial Dysostosis * genetics   MeSH
• Mutagenesis MeSH
• Mice MeSH
• Ribosomes genetics   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH