The distribution and morphology of neuronal degeneration were observed and analyzed in each sector of the zona incerta in a lithium‑pilocarpine (LiCl) Wistar rat model of status epilepticus in 12, 15, 18, 21, and 25‑day‑old rats and survival intervals of 4, 8, 12, 24, and 48 hours. Status epilepticus was induced via intraperitoneal (IP) injection of LiCl (3 mmol/kg) 24 hours before an injection of pilocarpine (40 mg/kg, IP). Motor seizures were suppressed by paraldehyde (0.3‑0.6 ml/kg, IP) two hours after status epilepticus onset. Animals were anesthetized using urethane and perfused with phosphate‑buffered saline followed by 4% paraformaldehyde. Brains were sectioned and Nissl stained for map guidance, with fluoro‑Jade B fluorescence used to detect degenerated neurons. Fluoro‑jade B‑positive neurons were plotted to a standard stereotaxic atlas, their distribution was quantified, and their long‑axis diameter was measured. Fluoro‑jade B‑positive neurons were found in pups aged 15 days and older 24 hours after status epilepticus, in which their numbers increased, and their perikaryon size decreased with advancing age. Thus, neuronal damage severity was dependent on age and survival interval. Neuronal damage was only found in the rostral sector of the zona incerta, a region that exhibits a small number of inhibitory neurons and is reciprocally connected to the limbic cortex. This system of hyperactivity, coupled with inhibitory neurons, may be the underlying cause of the neuronal degeneration and explain why it was confined to the rostral sector of the zona incerta.
- MeSH
- chlorid lithný toxicita MeSH
- degenerace nervu * patologie etiologie MeSH
- fluoresceiny MeSH
- krysa rodu Rattus MeSH
- modely nemocí na zvířatech MeSH
- neurony * patologie MeSH
- novorozená zvířata MeSH
- pilokarpin toxicita MeSH
- potkani Wistar MeSH
- status epilepticus * patologie chemicky indukované komplikace MeSH
- věkové faktory MeSH
- zona incerta * patologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chlorid lithný MeSH
- fluoresceiny MeSH
- fluoro jade MeSH Prohlížeč
- pilokarpin MeSH
This study investigated the striatopallidal complex's involvement in status epilepticus (SE) caused by morphological neurodegenerative changes in a post-natal immature developing brain in a lithium-pilocarpine male Wistar albino rat model of mesial temporal lobe epilepsy. One hundred experimental pups were grouped by age as follows: 12, 15, 18, 21, and 25 days. SE was induced by lithium-pilocarpine. Brain sections were microscopically examined by Fluoro-Jade B fluorescence stain at intervals of 4, 12, 24, and 48 h and 1 week after SE. Each interval was composed of four induced SE pups and a control. Fluoro-Jade B positive neurons in the dorsal striatum (DS) were screened and plotted on stereotaxic rat brain maps. The DS showed consistent neuronal damage in pups aged 18, 21, and 25 days. The peak of the detected damage was observed in pups aged 18 days, and the start of the morphological sequela was observed 12 h post SE. The neuronal damage in the DS was distributed around its periphery, extending medially. The damaged neurons showed intense Fluoro-Jade B staining at the intervals of 12 and 24 h post SE. SE neuronal damage was evidenced in the post-natal developing brain selectively in the DS and was age-dependent with differing morphological sequela.
- Klíčová slova
- basal ganglia, degenerative neuronal changes, dorsal striatum, epilepsy, rat brain, seizure, status epilepticus,
- MeSH
- corpus striatum * patologie metabolismus MeSH
- epilepsie temporálního laloku * patologie chemicky indukované MeSH
- krysa rodu Rattus MeSH
- modely nemocí na zvířatech MeSH
- neurony patologie metabolismus MeSH
- pilokarpin MeSH
- potkani Wistar MeSH
- status epilepticus * patologie chemicky indukované MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- pilokarpin MeSH
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.
- Klíčová slova
- Alexander disease, GFAP, iPS cells, neural organoids,
- 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
- Názvy látek
- GFAP protein, human MeSH Prohlížeč
- gliový fibrilární kyselý protein * MeSH
Microtubule associated proteins (MAPs) are widely expressed in the central nervous system, and have established roles in cell proliferation, myelination, neurite formation, axon specification, outgrowth, dendrite, and synapse formation. We report eleven individuals from seven families harboring predicted pathogenic biallelic, de novo, and heterozygous variants in the NAV3 gene, which encodes the microtubule positive tip protein neuron navigator 3 (NAV3). All affected individuals have intellectual disability (ID), microcephaly, skeletal deformities, ocular anomalies, and behavioral issues. In mouse brain, Nav3 is expressed throughout the nervous system, with more prominent signatures in postmitotic, excitatory, inhibiting, and sensory neurons. When overexpressed in HEK293T and COS7 cells, pathogenic variants impaired NAV3 ability to stabilize microtubules. Further, knocking-down nav3 in zebrafish led to severe morphological defects, microcephaly, impaired neuronal growth, and behavioral impairment, which were rescued with co-injection of WT NAV3 mRNA and not by transcripts encoding the pathogenic variants. Our findings establish the role of NAV3 in neurodevelopmental disorders, and reveal its involvement in neuronal morphogenesis, and neuromuscular responses.
- MeSH
- Cercopithecus aethiops MeSH
- COS buňky MeSH
- dánio pruhované genetika MeSH
- dítě MeSH
- HEK293 buňky MeSH
- lidé MeSH
- mentální retardace * genetika MeSH
- mikrocefalie * genetika patologie MeSH
- myši MeSH
- neurony metabolismus patologie MeSH
- předškolní dítě MeSH
- proteiny asociované s mikrotubuly genetika metabolismus MeSH
- proteiny nervové tkáně genetika metabolismus MeSH
- vývojové poruchy u dětí * genetika MeSH
- zvířata MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- NAV3 protein, human MeSH Prohlížeč
- proteiny asociované s mikrotubuly MeSH
- proteiny nervové tkáně MeSH
According to experimental and clinical studies, status epilepticus (SE) causes neurodegenerative morphological changes not only in the hippocampus and other limbic structures, it also affects the thalamus and the neocortex. In addition, several studies reported atrophy, metabolic changes, and neuronal degeneration in the dorsal striatum. The literature lacks studies investigating potential neuronal damage in the ventral component of the striatopallidal complex (ventral striatum [VS] and ventral pallidum) in SE experimentations. To better understand the development of neuronal damage in the striatopallidal complex associated with SE, the detected neuronal degeneration in the compartments of the VS, namely, the nucleus accumbens (NAc) and the olfactory tubercle (OT), was analyzed. The experiments were performed on Wistar rats at age of 25-day-old pups and 3-month-old adult animals. Lithium-pilocarpine model of SE was used. Lithium chloride (3 mmol/kg, ip) was injected 24 h before administering pilocarpine (40 mg/kg, ip). This presented study demonstrates the variability of post SE neuronal damage in 25-day-old pups in comparison with 3-month-old adult rats. The NAc exhibited small to moderate number of Fluoro-Jade B (FJB)-positive neurons detected 4 and 8 h post SE intervals. The number of degenerated neurons in the shell subdivision of the NAc significantly increased at survival interval of 12 h after the SE. FJB-positive neurons were evidently more prominent occupying the whole anteroposterior and mediolateral extent of the nucleus at longer survival intervals of 24 and 48 h after the SE. This was also the case in the bordering vicinity between the shell and the core compartments but with clusters of degenerating cells. The severity of damage of the shell subdivision of the NAc reached its peak at an interval of 24 h post SE. Isolated FJB-positive neurons were detected in the ventral peripheral part of the core compartment. Degenerated neurons persisted in the shell subdivision of the NAc 1 week after SE. However, the quantity of cell damage had significantly reduced in comparison with the aforementioned shorter intervals. The third layer of the OT exhibited more degenerated neurons than the second layer. The FJB-positive cells in the young animals were higher than in the adult animals. The morphology of those cells was identical in the two age groups except in the OT.
- Klíčová slova
- basal ganglia, degenerative neuronal changes, epilepsy, nucleus accumbens, olfactory tubercle, seizure, status epilepticus, ventral pallidum, ventral striatum,
- MeSH
- chlorid lithný toxicita MeSH
- degenerace nervu * patologie chemicky indukované MeSH
- fluoresceiny MeSH
- krysa rodu Rattus MeSH
- modely nemocí na zvířatech MeSH
- neurony patologie MeSH
- novorozená zvířata MeSH
- pilokarpin toxicita MeSH
- potkani Wistar * MeSH
- status epilepticus * chemicky indukované patologie MeSH
- striatum ventrale patologie MeSH
- věkové faktory MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Názvy látek
- chlorid lithný MeSH
- fluoresceiny MeSH
- fluoro jade MeSH Prohlížeč
- pilokarpin MeSH
Huntington´s disease (HD) is a progressive neurodegenerative disease with onset in adulthood that leads to a complete disability and death in approximately 20 years after onset of symptoms. HD is caused by an expansion of a CAG triplet in the gene for huntingtin. Although the disease causes most damage to striatal neurons, other parts of the nervous system and many peripheral tissues are also markedly affected. Besides huntingtin malfunction, mitochondrial impairment has been previously described as an important player in HD. This study focuses on mitochondrial structure and function in cultivated skin fibroblasts from 10 HD patients to demonstrate mitochondrial impairment in extra-neuronal tissue. Mitochondrial structure, mitochondrial fission, and cristae organization were significantly disrupted and signs of elevated apoptosis were found. In accordance with structural changes, we also found indicators of functional alteration of mitochondria. Mitochondrial disturbances presented in fibroblasts from HD patients confirm that the energy metabolism damage in HD is not localized only to the central nervous system, but also may play role in the pathogenesis of HD in peripheral tissues. Skin fibroblasts can thus serve as a suitable cellular model to make insight into HD pathobiochemical processes and for the identification of possible targets for new therapies.
- Klíčová slova
- Huntington’s disease, fibroblasts, mitochondrial dysfunction, mitochondrial network, oxidative phosphorylation system, ultrastructure,
- MeSH
- dospělí MeSH
- fibroblasty metabolismus MeSH
- Huntingtonova nemoc * genetika metabolismus patologie MeSH
- lidé MeSH
- mitochondrie patologie MeSH
- neurodegenerativní nemoci * metabolismus patologie MeSH
- neurony patologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Brain edema - a frequently fatal pathological state in which brain volume increases resulting in intracranial pressure elevation - can result from almost any insult to the brain, including traumatic brain injury. For many years, the objective of experimental studies was to find a method to prevent the development of brain edema at the onset. From this perspective, the use of methylprednisolone (MP) appears promising. High molecular MP (MW>50 kDa) can be incorporated into the brain - in the conditions of the experimental model - either by osmotic blood-brain barrier disruption (BBBd) or during the induction of cellular edema by water intoxication (WI) - a condition that increases the BBB permeability. The time window for administration of the MP should be at the earliest stages of edema. The neuroprotective effect of MP on the permeability of cytoplasmatic membranes of neuronal populations was proved. MP was administrated in three alternative ways: intraperitoneally during the induction of cytotoxic edema or immediately after finishing cytotoxic edema induction in a dose of 100 mg/kg b.w.; into the internal carotid artery within 2 h after finishing cytotoxic edema induction in a dose of 50 mg/kg b.w.; into internal carotid artery 10 min after edema induction by BBBd in a dose of 50 mg/kg b.w.
- MeSH
- edém mozku farmakoterapie metabolismus patologie MeSH
- glukokortikoidy farmakologie MeSH
- hematoencefalická bariéra účinky léků metabolismus patologie MeSH
- kapilární permeabilita účinky léků MeSH
- krysa rodu Rattus MeSH
- methylprednisolon farmakologie MeSH
- modely nemocí na zvířatech MeSH
- mozek účinky léků metabolismus patologie MeSH
- neurony účinky léků metabolismus patologie MeSH
- neuroprotektivní látky farmakologie MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- glukokortikoidy MeSH
- methylprednisolon MeSH
- neuroprotektivní látky MeSH
Alterations in mitochondrial dynamics, including their intracellular trafficking, are common early manifestations of neuronal degeneration. However, current methodologies used to study mitochondrial trafficking events rely on parameters that are primarily altered in later stages of neurodegeneration. Our objective was to establish a reliable applied statistical analysis to detect early alterations in neuronal mitochondrial trafficking. We propose a novel quantitative analysis of mitochondria trajectories based on innovative movement descriptors, including straightness, efficiency, anisotropy, and kurtosis. We evaluated time- and dose-dependent alterations in trajectory descriptors using biological data from differentiated SH-SY5Y cells treated with the mitochondrial toxicants 6-hydroxydopamine and rotenone. MitoTracker Red CMXRos-labelled mitochondria movement was analyzed by total internal reflection fluorescence microscopy followed by computational modelling to describe the process. Based on the aforementioned trajectory descriptors, this innovative analysis of mitochondria trajectories provides insights into mitochondrial movement characteristics and can be a consistent and sensitive method to detect alterations in mitochondrial trafficking occurring in the earliest time points of neurodegeneration.
- Klíčová slova
- exploratory data analysis, live cell imaging, mitochondria movement, neurotoxicants, principal component analysis, trajectory descriptors,
- MeSH
- adrenergní látky škodlivé účinky MeSH
- buněčná diferenciace MeSH
- lidé MeSH
- mitochondriální dynamika * MeSH
- mitochondrie účinky léků patologie MeSH
- neuroblastom chemicky indukované patologie MeSH
- neurony účinky léků patologie MeSH
- oxidopamin škodlivé účinky MeSH
- rotenon škodlivé účinky MeSH
- rozpřahující látky škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- adrenergní látky MeSH
- oxidopamin MeSH
- rotenon MeSH
- rozpřahující látky MeSH
AIMS: Tuberous sclerosis complex (TSC) is a genetic disorder associated with dysregulation of the mechanistic target of rapamycin complex 1 (mTORC1) signalling pathway. Neurodevelopmental disorders, frequently present in TSC, are linked to cortical tubers in the brain. We previously reported microRNA-34a (miR-34a) among the most upregulated miRs in tubers. Here, we characterised miR-34a expression in tubers with the focus on the early brain development and assessed the regulation of mTORC1 pathway and corticogenesis by miR-34a. METHODS: We analysed the expression of miR-34a in resected cortical tubers (n = 37) compared with autopsy-derived control tissue (n = 27). The effect of miR-34a overexpression on corticogenesis was assessed in mice at E18. The regulation of the mTORC1 pathway and the expression of the bioinformatically predicted target genes were assessed in primary astrocyte cultures from three patients with TSC and in SH-SY5Y cells following miR-34a transfection. RESULTS: The peak of miR-34a overexpression in tubers was observed during infancy, concomitant with the presence of pathological markers, particularly in giant cells and dysmorphic neurons. miR-34a was also strongly expressed in foetal TSC cortex. Overexpression of miR-34a in mouse embryos decreased the percentage of cells migrated to the cortical plate. The transfection of miR-34a mimic in TSC astrocytes negatively regulated mTORC1 and decreased the expression of the target genes RAS related (RRAS) and NOTCH1. CONCLUSIONS: MicroRNA-34a is most highly overexpressed in tubers during foetal and early postnatal brain development. miR-34a can negatively regulate mTORC1; however, it may also contribute to abnormal corticogenesis in TSC.
- Klíčová slova
- TSC, mechanistic target of rapamycin, miRNA, migration, neurodevelopmental disorder,
- MeSH
- astrocyty metabolismus MeSH
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mikro RNA genetika metabolismus MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mozek růst a vývoj patologie MeSH
- mozková kůra patologie MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- neurony patologie MeSH
- předškolní dítě MeSH
- signální transdukce genetika MeSH
- tuberózní skleróza komplikace genetika patologie MeSH
- zvířata MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- myši MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- mikro RNA MeSH
- MIRN34 microRNA, human MeSH Prohlížeč
- MIRN34a microRNA, mouse MeSH Prohlížeč
Huntington's disease (HD), as well as Parkinson's disease and Alzheimer's disease, belong to a group of neurodegenerative diseases characterized by common features, such as the progressive loss of neurons and the presence of pathogenic forms of misfolded protein aggregates. A quality control system such as autophagy is crucial for the clearance of protein aggregates and dysfunctional organelles and thus essential for the maintenance of neuronal homeostasis. The constant high energy demand of neuronal tissue links neurodegeneration to mitochondria. Inefficient removal of damaged mitochondria is thought to contribute to the pathogenesis of neurodegenerative diseases such as HD. In addition, direct involvement of the huntingtin protein in the autophagic machinery has been described. In this review, we focus on mitophagy, a selective form of autophagy responsible for mitochondrial turnover. We also discuss the relevance of pharmacological regulation of mitophagy in the future therapeutic approach to neurodegenerations, including HD.
- Klíčová slova
- Huntington's disease, Mitochondria, Mitophagy, Mitophagy adaptors, Pharmacological induction of mitophagy,
- MeSH
- biologické přípravky terapeutické užití MeSH
- Huntingtonova nemoc farmakoterapie genetika metabolismus patologie MeSH
- lidé MeSH
- mitochondrie genetika metabolismus patologie MeSH
- mitofagie fyziologie MeSH
- neurony metabolismus patologie MeSH
- neuroprotektivní látky terapeutické užití MeSH
- protein huntingtin genetika metabolismus MeSH
- proteinové agregáty fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- biologické přípravky MeSH
- neuroprotektivní látky MeSH
- protein huntingtin MeSH
- proteinové agregáty MeSH