AIMS: Endoplasmic reticulum stress followed by the unfolded protein response is one of the cellular mechanisms contributing to the progression of α-synuclein pathology in Parkinson's disease and other Lewy body diseases. We aimed to investigate the activation of endoplasmic reticulum stress and its correlation with α-synuclein pathology in human post-mortem brain tissue. METHODS: We analysed brain tissue from 45 subjects-14 symptomatic patients with Lewy body disease, 19 subjects with incidental Lewy body disease, and 12 healthy controls. The analysed brain regions included the medulla, pons, midbrain, striatum, amygdala and entorhinal, temporal, frontal and occipital cortex. We analysed activation of endoplasmic reticulum stress via levels of the unfolded protein response-related proteins (Grp78, eIF2α) and endoplasmic reticulum stress-regulating neurotrophic factors (MANF, CDNF). RESULTS: We showed that regional levels of two endoplasmic reticulum-localised neurotrophic factors, MANF and CDNF, did not change in response to accumulating α-synuclein pathology. The concentration of MANF negatively correlated with age in specific regions. eIF2α was upregulated in the striatum of Lewy body disease patients and correlated with increased α-synuclein levels. We found the upregulation of chaperone Grp78 in the amygdala and nigral dopaminergic neurons of Lewy body disease patients. Grp78 levels in the amygdala strongly correlated with soluble α-synuclein levels. CONCLUSIONS: Our data suggest a strong but regionally specific change in Grp78 and eIF2α levels, which positively correlates with soluble α-synuclein levels. Additionally, MANF levels decreased in dopaminergic neurons in the substantia nigra. Our research suggests that endoplasmic reticulum stress activation is not associated with Lewy pathology but rather with soluble α-synuclein concentration and disease progression.
- Klíčová slova
- ER stress, Lewy body disease, Parkinson's disease, alpha‐synuclein, unfolded protein response,
- MeSH
- alfa-synuklein * metabolismus MeSH
- biologické markery metabolismus MeSH
- chaperon endoplazmatického retikula BiP * metabolismus MeSH
- demence s Lewyho tělísky * patologie metabolismus MeSH
- eukaryotický iniciační faktor 2 * metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- mozek metabolismus patologie MeSH
- neurotrofní faktory metabolismus MeSH
- proteiny tepelného šoku * metabolismus MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- signální dráha UPR * fyziologie MeSH
- stres endoplazmatického retikula fyziologie MeSH
- upregulace * MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- alfa-synuklein * MeSH
- biologické markery MeSH
- chaperon endoplazmatického retikula BiP * MeSH
- EIF2S1 protein, human MeSH Prohlížeč
- eukaryotický iniciační faktor 2 * MeSH
- HSPA5 protein, human MeSH Prohlížeč
- MANF protein, human MeSH Prohlížeč
- neurotrofní faktory MeSH
- proteiny tepelného šoku * MeSH
- SNCA protein, human MeSH Prohlížeč
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
- MeSH
- imunohistochemie MeSH
- kojenec MeSH
- lidé MeSH
- metylace DNA MeSH
- předškolní dítě MeSH
- rhabdoidní nádor diagnóza metabolismus MeSH
- senzitivita a specificita MeSH
- teratom diagnóza metabolismus MeSH
- tyrosinasa analýza metabolismus MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- dopisy MeSH
- práce podpořená grantem MeSH
- Názvy látek
- tyrosinasa MeSH
Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is an early-onset neurodegenerative disease that includes progressive cerebellar dysfunction. ARSACS is caused by an autosomal recessive loss-of-function mutation in the SACS gene, which encodes for SACSIN. Although animal models are still necessary to investigate the role of SACSIN in the pathology of this disease, more reliable human cellular models need to be generated to better understand the cerebellar pathophysiology of ARSACS. The discovery of human induced pluripotent stem cells (hiPSC) has permitted the derivation of patient-specific cells. These cells have an unlimited self-renewing capacity and the ability to differentiate into different neural cell types, allowing studies of disease mechanism, drug discovery and cell replacement therapies. In this study, we discuss how the hiPSC-derived cerebellar organoid culture offers novel strategies for targeting the pathogenic mutations related to ARSACS. We also highlight the advantages and challenges of this 3D cellular model, as well as the questions that still remain unanswered.
- Klíčová slova
- ARSACS, 3D organoids, ataxia, cerebellum, disease modelling, induced pluripotent stem cells,
- MeSH
- indukované pluripotentní kmenové buňky MeSH
- lidé MeSH
- mozeček patologie MeSH
- nemoci mozečku patologie terapie MeSH
- spinocerebelární ataxie vrozené patologie terapie MeSH
- svalová spasticita patologie terapie MeSH
- teoretické modely MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
AIMS: In Wilson disease (WD), T2/T2*-weighted (T2*w) MRI frequently shows hypointensity in the basal ganglia that is suggestive of paramagnetic deposits. It is currently unknown whether this hypointensity is related to copper or iron deposition. We examined the neuropathological correlates of this MRI pattern, particularly in relation to iron and copper concentrations. METHODS: Brain slices from nine WD and six control cases were investigated using a 7T-MRI system. High-resolution T2*w images were acquired and R2* parametric maps were reconstructed using a multigradient recalled echo sequence. R2* was measured in the globus pallidus (GP) and the putamen. Corresponding histopathological sections containing the lentiform nucleus were examined using Turnbull iron staining, and double staining combining Turnbull with immunohistochemistry for macrophages or astrocytes. Quantitative densitometry of the iron staining as well as copper and iron concentrations were measured in the GP and putamen and correlated with R2* values. RESULTS: T2*w hypointensity in the GP and/or putamen was apparent in WD cases and R2* values correlated with quantitative densitometry of iron staining. In WD, iron and copper concentrations were increased in the putamen compared to controls. R2* was correlated with the iron concentration in the GP and putamen, whereas no correlation was observed for the copper concentration. Patients with more pronounced pathological severity in the putamen displayed increased iron concentration, which correlated with an elevated number of iron-containing macrophages. CONCLUSIONS: T2/T2*w hypointensity observed in vivo in the basal ganglia of WD patients is related to iron rather than copper deposits.
- Klíčová slova
- Wilson disease, brain, iron accumulation, pathology, post mortem 7T MRI,
- MeSH
- astrocyty MeSH
- bazální ganglia diagnostické zobrazování metabolismus patologie MeSH
- corpus striatum metabolismus patologie MeSH
- dospělí MeSH
- hepatolentikulární degenerace diagnostické zobrazování metabolismus patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- makrofágy MeSH
- měď metabolismus MeSH
- mladý dospělý MeSH
- železo metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- měď MeSH
- železo MeSH
The extracellular matrix (ECM) and changes in the size and geometry of the extracellular space (ECS) in tumour tissue are thought to be of critical importance in influencing the migratory abilities of tumour cells as well as the delivery of therapeutic agents into the tumour. In 21 astrocytic neoplasms, the ECM composition was investigated in situ by the immunohistochemical detection of ECM glycoproteins (tenascin, laminin, vitronectin, fibronectin, collagen types I-VI). To explain the changes in ECS size and to detect barriers to diffusion in the tumour tissue, the ECM composition, the cellularity, the density of glial fibrillary acidic protein (GFAP)-positive tumour cell processes and the proliferative activity of the tumours were compared with the size and geometry of the ECS. The ECS volume fraction and the complex of hindrances to diffusion in the ECS (i.e. the tortuosity) were revealed by the real-time iontophoretic tetramethylammonium method. Increased proliferative activity of the tumours correlated with increased ECS volume fraction and tortuosity. The tortuosity of the tumour tissue was not significantly influenced by tumour cell density. Higher tortuosity was found in low-grade astrocytomas associated with the presence of a dense net of GFAP-positive fibrillary processes of the tumour cells. The increase in tortuosity in high-grade tumours correlated with an increased accumulation of ECM molecules, particularly of tenascin. We conclude that the increased malignancy of astrocytic tumours correlates with increases in both ECS volume and ECM deposition.
- MeSH
- astrocytom metabolismus patologie MeSH
- buněčné dělení MeSH
- difuze MeSH
- extracelulární matrix - proteiny metabolismus MeSH
- extracelulární matrix metabolismus patologie MeSH
- glioblastom metabolismus patologie MeSH
- gliový fibrilární kyselý protein metabolismus MeSH
- glykoproteiny metabolismus MeSH
- imunoenzymatické techniky MeSH
- imunohistochemie MeSH
- iontoforéza MeSH
- lidé MeSH
- nádory mozku metabolismus patologie MeSH
- senioři MeSH
- spánkový lalok metabolismus patologie MeSH
- zalévání tkání do parafínu MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- extracelulární matrix - proteiny MeSH
- gliový fibrilární kyselý protein MeSH
- glykoproteiny MeSH