Alexander disease (AxD) is a rare and severe neurodegenerative disorder caused by mutations in glial fibrillary acidic protein (GFAP). While the exact disease mechanism remains unknown, previous studies suggest that mutant GFAP influences many cellular processes, including cytoskeleton stability, mechanosensing, metabolism, and proteasome function. While most studies have primarily focused on GFAP-expressing astrocytes, GFAP is also expressed by radial glia and neural progenitor cells, prompting questions about the impact of GFAP mutations on central nervous system (CNS) development. In this study, we observed impaired differentiation of astrocytes and neurons in co-cultures of astrocytes and neurons, as well as in neural organoids, both generated from AxD patient-derived induced pluripotent stem (iPS) cells with a GFAPR239C mutation. Leveraging single-cell RNA sequencing (scRNA-seq), we identified distinct cell populations and transcriptomic differences between the mutant GFAP cultures and a corrected isogenic control. These findings were supported by results obtained with immunocytochemistry and proteomics. In co-cultures, the GFAPR239C mutation resulted in an increased abundance of immature cells, while in unguided neural organoids and cortical organoids, we observed altered lineage commitment and reduced abundance of astrocytes. Gene expression analysis revealed increased stress susceptibility, cytoskeletal abnormalities, and altered extracellular matrix and cell-cell communication patterns in the AxD cultures, which also exhibited higher cell death after stress. Overall, our results point to altered cell differentiation in AxD patient-derived iPS-cell models, opening new avenues for AxD research.
- MeSH
- Alexanderova nemoc * genetika patologie metabolismus MeSH
- astrocyty * metabolismus patologie MeSH
- buněčná diferenciace * fyziologie MeSH
- gliový fibrilární kyselý protein * metabolismus genetika MeSH
- indukované pluripotentní kmenové buňky * metabolismus MeSH
- kokultivační techniky MeSH
- kultivované buňky MeSH
- lidé MeSH
- mutace MeSH
- nervové kmenové buňky metabolismus MeSH
- neurony metabolismus patologie MeSH
- organoidy metabolismus patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Olfactory sensitivity to odorant molecules is a complex biological function influenced by both endogenous factors, such as genetic background and physiological state, and exogenous factors, such as environmental conditions. In animals, this vital ability is mediated by olfactory sensory neurons (OSNs), which are distributed across several specialized olfactory subsystems depending on the species. Using the phosphorylation of the ribosomal protein S6 (rpS6) in OSNs following sensory stimulation, we developed an ex vivo assay allowing the simultaneous conditioning and odorant stimulation of different mouse olfactory subsystems, including the main olfactory epithelium, the vomeronasal organ, and the Grueneberg ganglion. This approach enabled us to observe odorant-induced neuronal activity within the different olfactory subsystems and to demonstrate the impact of environmental conditioning, such as temperature variations, on olfactory sensitivity, specifically in the Grueneberg ganglion. We further applied our rpS6-based assay to the human olfactory system and demonstrated its feasibility. Our findings show that analyzing rpS6 signal intensity is a robust and highly reproducible indicator of neuronal activity across various olfactory systems, while avoiding stress and some experimental limitations associated with in vivo exposure. The potential extension of this assay to other conditioning paradigms and olfactory systems, as well as its application to other animal species, including human olfactory diagnostics, is also discussed.
- MeSH
- čich fyziologie MeSH
- čichová sliznice metabolismus MeSH
- čichové buňky * metabolismus fyziologie MeSH
- fosforylace MeSH
- lidé MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- odoranty analýza MeSH
- ribozomální protein S6 * metabolismus MeSH
- vomeronazální orgán metabolismus fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Single-photon optogenetics enables precise, cell-type-specific modulation of neuronal circuits, making it a crucial tool in neuroscience. Its miniaturization in the form of fully implantable wide-field stimulator arrays enables long-term interrogation of cortical circuits and bears promise for brain-machine interfaces for sensory and motor function restoration. However, achieving selective activation of functional cortical representations poses a challenge, as studies show that targeted optogenetic stimulation results in activity spread beyond one functional domain. While recurrent network mechanisms contribute to activity spread, here we demonstrate with detailed simulations of isolated pyramidal neurons from cats of unknown sex that already neuron morphology causes a complex spread of optogenetic activity at the scale of one cortical column. Since the shape of a neuron impacts its optogenetic response, we find that a single stimulator at the cortical surface recruits a complex spatial distribution of neurons that can be inhomogeneous and vary with stimulation intensity and neuronal morphology across layers. We explore strategies to enhance stimulation precision, finding that optimizing stimulator optics may offer more significant improvements than the preferentially somatic expression of the opsin through genetic targeting. Our results indicate that, with the right optical setup, single-photon optogenetics can precisely activate isolated neurons at the scale of functional cortical domains spanning several hundred micrometers.
- MeSH
- kočky MeSH
- modely neurologické MeSH
- mozková kůra fyziologie cytologie MeSH
- neurony fyziologie MeSH
- optogenetika * metody MeSH
- pyramidové buňky fyziologie MeSH
- světelná stimulace metody MeSH
- zvířata MeSH
- Check Tag
- kočky MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- elektroencefalografie MeSH
- kognice fyziologie MeSH
- kognitivní věda metody MeSH
- lidé MeSH
- mozek fyziologie MeSH
- neurony fyziologie MeSH
- percepce fyziologie MeSH
- reflex fyziologie MeSH
- stadia spánku MeSH
- vědomí * fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
T-type calcium channels perform crucial physiological roles across a wide spectrum of tissues, spanning both neuronal and non-neuronal system. For instance, they serve as pivotal regulators of neuronal excitability, contribute to cardiac pacemaking, and mediate the secretion of hormones. These functions significantly hinge upon the intricate interplay of T-type channels with interacting proteins that modulate their expression and function at the plasma membrane. In this review, we offer a panoramic exploration of the current knowledge surrounding these T-type channel interactors, and spotlight certain aspects of their potential for drug-based therapeutic intervention.
Cíl: Cílem této studie bylo analyzovat klinické aspekty diagnostiky a léčby léze lícního nervu (LLN) u dětí v terciálním centru. Zaměřuje se na demografii, etiologii, diagnostický a terapeutický proces, míru úpravy po terapii a rozsah relapsů. Materiál a metodika: Retrospektivní studie, 572 pacientů (0–18 let), léčených ve fakultní nemocnici s diagnózou LLN v průběhu 10 let (2011–2021). Data byla získávaná z pacientské dokumentace. Analyzovány byly následující parametry: věk, pohlaví, strana léze, etiologie, diagnostický proces zahrnující radiologické vyšetření, léčebný proces, úprava léze po terapii a míra relapsu. Výsledky: LLN se vyskytla v 554 případech jako unilaterální, v 18 jako bilaterální bez signifikantní stranové diference. Dívky byly postiženy v 301 (52,6 %) a chlapci v 271 (47,4 %) případech. Medián věku byl stanoven na 9,4 ± 4,7 roku. Průměrné House-Brackmann (HB) skóre bylo 3,6 ± 1,0. Jako dvě nejčastější příčiny jsme prokázali infekční 264 (46,2 %) a idiopatickou 255 (44,6 %). Borelióza byla nejčastěji zastoupenou infekční příčinou u 216 (81,8 %) případů. Třetí nejčastější příčina byla neoplastická u 15 (2,6 %) případů. Následovaly traumatická, kongenitální a další. Nekompletní paréza byla detekována u 556 (97,2 %) případů a kompletní u 16 (2,8 %). Kortikosteroidy byly podány u 360 pacientů, antibiotika/antivirotika u 311 pacientů. Chirurgický výkon podstoupilo 26 pacientů. Úpravu po terapii jsme zaznamenali u 94,7 % pacientů, nezaznamenali u 5,3 %, u 1 % je údaj neznámý. U infekční příčiny prokázalo úpravu po terapii 99,2 %, u idiopatické 98 % pacientů. Pacienti s infekční, idiopatickou a traumatickou příčinou měli vyšší míru úpravy po terapii než pacienti s neoplastickou příčinou. Závěr: LLN je relativně častá akutní diagnóza v dětském věku. Bylo popsáno velké množství různých příčin, nejčastěji se vyskytuje příčina infekční a idiopatická. Pro správnou diagnózu je důležitá detailní anamnéza a klinické vyšetřeni. V léčbě převažuje terapie kortikosteroidy a antibiotiky. Názory na léčbu jsou kontroverzní. Prognóza LLN u děti je zpravidla dobrá.
Aim: This study aimed to analyze the different characteristics of FNLs in children focusing on demographics, etiology, diagnostic and therapeutic process, improvement after therapy, and relapse rate in a tertiary center. Materials and methods: A retrospective study of 572 children (0 to 18 years) who were admitted to the University Hospital with facial nerve lesion (FNL) during a 10-year period (2011–2021). The data were gathered from patients´ medical files to analyze age, sex, side of FNL, etiology, the diagnostic process including radiological examinations, treatment methods, improvement after therapy, and relapse rate. Results: There were 554 unilateral and 18 bilateral cases without significant laterality differences. Girls were affected in 301 (52.6%) cases and boys in 271 (47.4%) cases. The median age was 9.4 ± 4.7 years. The mean House-Brackmann (HB) score was 3.6 ± 1.0. Two main causes whose representation was balanced were detected. Infectious causes occurred in 264 (46.2%) cases and idiopathic causes occurred in 255 (44.6%) cases. Borreliosis was the most common infectious cause in 216 (81.8%) cases. The third most common cause was of neoplastic origin in 15 (2.6%) cases. The following causes were traumatic, congenital, and others. Incomplete FNL was detected in 556 (97.2%) cases and complete FNL was found in 16 (2.8%) cases. Corticosteroids were administered in 360 patients, and antibiotics/ antivirals were given to 311 patients. Surgery was performed in 26 patients. 94.7 % of patients showed improvement after therapy while 5.3% did not, and 1.0% had an unknown outcome. For the infectious causes, improvement after therapy was seen in 99.2% of patients and idiopathic causes saw improvement in 98% of patients. Patients with infectious, idiopathic, and traumatic causes of paresis had a higher percentage of recovery compared to patients with neoplastic causes. Conclusions: FNL in children is a relatively common acute condition in pediatric care. Many different causes of FNL were described, the most common being infectious and idiopathic. A detailed clinical history and clinical examination are mandatory. Corticosteroids and antibiotics are most commonly prescribed medicaments. Opinions on the treatment remain controversial. The prognosis of FNL in children is usually favorable.
- MeSH
- dítě MeSH
- lidé MeSH
- lymská neuroborelióza komplikace MeSH
- mladiství MeSH
- motorické neurony patologie MeSH
- nemoci lícního nervu * epidemiologie etiologie patologie terapie MeSH
- recidiva MeSH
- retrospektivní studie MeSH
- statistika jako téma MeSH
- věkové faktory MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition characterised by a progressive loss of motor neurons controlling voluntary muscle activity. The disease manifests through a variety of motor dysfunctions related to the extent of damage and loss of neurons at different anatomical locations. Despite extensive research, it remains unclear why some motor neurons are especially susceptible to the disease, while others are affected less or even spared. In this article, we review the neurobiological mechanisms, neurochemical profiles, and morpho-functional characteristics of various motor neuron groups and types of motor units implicated in their differential exposure to degeneration. We discuss specific cell-autonomous (intrinsic) and extrinsic factors influencing the vulnerability gradient of motor units and motor neuron types to ALS, with their impact on disease manifestation, course, and prognosis, as revealed in preclinical and clinical studies. We consider the outstanding challenges and emerging opportunities for interpreting the phenotypic and mechanistic variability of the disease to identify targets for clinical interventions.
- MeSH
- amyotrofická laterální skleróza * MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- motorické neurony MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Adenosine deaminase acting on RNA 1 (ADAR1) is the principal enzyme for the adenosine-to-inosine RNA editing that prevents the aberrant activation of cytosolic nucleic acid sensors by endogenous double stranded RNAs and the activation of interferon-stimulated genes. In mice, the conditional neural crest deletion of Adar1 reduces the survival of melanocytes and alters the differentiation of Schwann cells that fail to myelinate nerve fibers in the peripheral nervous system. These myelination defects are partially rescued upon the concomitant removal of the Mda5 antiviral dsRNA sensor in vitro, suggesting implication of the Mda5/Mavs pathway and downstream effectors in the genesis of Adar1 mutant phenotypes. By analyzing RNA-Seq data from the sciatic nerves of mouse pups after conditional neural crest deletion of Adar1 (Adar1cKO), we here identified the transcription factors deregulated in Adar1cKO mutants compared to the controls. Through Adar1;Mavs and Adar1cKO;Egr1 double-mutant mouse rescue analyses, we then highlighted that the aberrant activation of the Mavs adapter protein and overexpression of the early growth response 1 (EGR1) transcription factor contribute to the Adar1 deletion associated defects in Schwann cell development in vivo. In silico and in vitro gene regulation studies additionally suggested that EGR1 might mediate this inhibitory effect through the aberrant regulation of EGR2-regulated myelin genes. We thus demonstrate the role of the Mda5/Mavs pathway, but also that of the Schwann cell transcription factors in Adar1-associated peripheral myelination defects.
- MeSH
- adenosindeaminasa * genetika metabolismus MeSH
- buněčná diferenciace * genetika MeSH
- crista neuralis * metabolismus MeSH
- IFIH1 genetika metabolismus MeSH
- myelinová pochva metabolismus MeSH
- myši knockoutované * MeSH
- myši MeSH
- Schwannovy buňky * metabolismus patologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Rasopathies are genetic disorders often associated with developmental delay and intellectual disability. Noonan syndrome (NS) is one of the most common Rasopathies, caused by mutations in PTPN11 in more than 50% of cases. In mammalian neurons, PTPN11 controls the trafficking of postsynaptic glutamate receptors. This process is disrupted in neurons expressing PTPN11 variants associated with Rasopathies and is thought to contribute to the cognitive impairments in Noonan syndrome. Recent work revealed presynaptic impairments upon expression of RASopathy-linked PTPN11 variants in Drosophila. However, the presynaptic role of PTPN11 has not yet been addressed in mammals. Here, we investigated membrane trafficking of synaptic vesicles in cultured mouse cortical neurons expressing Rasopathy-associated PTPN11D61Y variant. We observed a significantly smaller readily releasable and total recycling pool of synaptic vesicles. The drop in synaptic vesicle release competence was accompanied by a decreased rate of SV retrieval. Interestingly, the presynaptic phenotype was evident in mature (DIV21) but not in immature (DIV12) neurons. Thus, our data reveal importance of balanced PTPN11 activity for normal trafficking of neurotransmitter-filled synaptic vesicles in the presynaptic ending of mature neurons.
- MeSH
- kultivované buňky MeSH
- mutace genetika MeSH
- myši MeSH
- neurony metabolismus MeSH
- stárnutí genetika metabolismus MeSH
- synaptické vezikuly * metabolismus MeSH
- tyrosinfosfatasa nereceptorového typu 11 * metabolismus genetika MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Skin uses interdependent cellular networks for barrier integrity and host immunity, but most underlying mechanisms remain obscure. Herein, we demonstrate that the human parasitic helminth Schistosoma mansoni inhibited pruritus evoked by itch-sensing afferents bearing the Mas-related G-protein-coupled receptor A3 (MrgprA3) in mice. MrgprA3 neurons controlled interleukin (IL)-17+ γδ T cell expansion, epidermal hyperplasia and host resistance against S. mansoni through shaping cytokine expression in cutaneous antigen-presenting cells. MrgprA3 neuron activation downregulated IL-33 but induced IL-1β and tumor necrosis factor in macrophages and type 2 conventional dendritic cells partially through the neuropeptide calcitonin gene-related peptide. Macrophages exposed to MrgprA3-derived secretions or bearing cell-intrinsic IL-33 deletion showed increased chromatin accessibility at multiple inflammatory cytokine loci, promoting IL-17/IL-23-dependent changes to the epidermis and anti-helminth resistance. This study reveals a previously unrecognized intercellular communication mechanism wherein itch-inducing MrgprA3 neurons initiate host immunity against skin-invasive parasites by directing cytokine expression patterns in myeloid antigen-presenting cell subsets.
- MeSH
- dendritické buňky imunologie MeSH
- interleukin 33 * metabolismus imunologie MeSH
- kůže imunologie parazitologie MeSH
- lidé MeSH
- makrofágy imunologie metabolismus MeSH
- myeloidní buňky imunologie metabolismus MeSH
- myši inbrední C57BL MeSH
- myši knockoutované MeSH
- myši MeSH
- neurony imunologie metabolismus MeSH
- pruritus imunologie MeSH
- receptory spřažené s G-proteiny * metabolismus imunologie genetika MeSH
- Schistosoma mansoni * imunologie MeSH
- schistosomiasis mansoni * imunologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
