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1.
Brain ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916996

RESUMO

Lewy body dementia and Alzheimer's disease (AD) are leading causes of cognitive impairment, characterized by distinct but overlapping neuropathological hallmarks. Lewy body disease (LBD) is characterized by alpha-synuclein aggregates in the form of Lewy bodies as well as the deposition of extracellular amyloid plaques, with many cases also exhibiting neurofibrillary tangle (NFT) pathology. In contrast, Alzheimer's disease is characterized by amyloid plaques and neurofibrillary tangles. Both conditions often co-occur with additional neuropathological changes, such as vascular disease and TDP-43 pathology. To elucidate shared and distinct molecular signatures underlying these mixed neuropathologies, we extensively analyzed transcriptional changes in the anterior cingulate cortex, a brain region critically involved in cognitive processes. We performed bulk tissue RNAseq from the anterior cingulate cortex and determined differentially expressed genes (q-value < 0.05) in control (n = 81), Lewy body disease (n = 436), Alzheimer's disease (n = 53), and pathological amyloid cases consisting of amyloid pathology with minimal or no tau pathology (n = 39). We used gene set enrichment and weighted gene correlation network analysis (WGCNA) to understand the pathways associated with each neuropathologically defined group. Lewy body disease cases had strong up-regulation of inflammatory pathways and down-regulation of metabolic pathways. The Lewy body disease cases were further subdivided into either high Thal amyloid, Braak NFT, or low pathological burden cohorts. Compared to the control cases, the Lewy body disease cohorts consistently showed up-regulation for genes involved in protein folding and cytokine immune response, as well as down-regulation of fatty acid metabolism. Surprisingly, concomitant tau pathology within the Lewy body disease cases resulted in no additional changes. Some core inflammatory pathways were shared between Alzheimer's disease and Lewy body disease but with numerous disease-specific changes. Direct comparison of Lewy body disease cohorts versus Alzheimer's disease cases revealed strong enrichment of synaptic signaling, behavior, and neuronal system pathways. Females had a stronger response overall in both Lewy body and Alzheimer's disease, with several sex-specific changes. Overall, the results identify genes commonly and uniquely dysregulated in neuropathologically defined Lewy body disease and Alzheimer's disease cases, shedding light on shared and distinct molecular pathways. Additionally, the study underscores the importance of considering sex-specific changes in understanding the complex transcriptional landscape of these neurodegenerative diseases.

2.
Alzheimers Dement ; 20(6): 4043-4065, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38713744

RESUMO

INTRODUCTION: Cerebrovascular dysfunction is a pathological hallmark of Alzheimer's disease (AD). Nevertheless, detecting cerebrovascular changes within bulk tissues has limited our ability to characterize proteomic alterations from less abundant cell types. METHODS: We conducted quantitative proteomics on bulk brain tissues and isolated cerebrovasculature from the same individuals, encompassing control (N = 28), progressive supranuclear palsy (PSP) (N = 18), and AD (N = 21) cases. RESULTS: Protein co-expression network analysis identified unique cerebrovascular modules significantly correlated with amyloid plaques, cerebrovascular amyloid angiopathy (CAA), and/or tau pathology. The protein products within AD genetic risk loci were concentrated within cerebrovascular modules. The overlap between differentially abundant proteins in AD cerebrospinal fluid (CSF) and plasma with cerebrovascular network highlighted a significant increase of matrisome proteins, SMOC1 and SMOC2, in CSF, plasma, and brain. DISCUSSION: These findings enhance our understanding of cerebrovascular deficits in AD, shedding light on potential biomarkers associated with CAA and vascular dysfunction in neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Biomarcadores , Proteômica , Humanos , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Masculino , Idoso , Feminino , Encéfalo/metabolismo , Tauopatias/líquido cefalorraquidiano , Tauopatias/sangue , Paralisia Supranuclear Progressiva/líquido cefalorraquidiano , Paralisia Supranuclear Progressiva/sangue , Angiopatia Amiloide Cerebral/líquido cefalorraquidiano , Angiopatia Amiloide Cerebral/genética , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Proteínas tau/líquido cefalorraquidiano
3.
Cancer Immunol Immunother ; 72(7): 1971-1989, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36928373

RESUMO

Bladder cancer (BC) can be divided into two subgroups depending on invasion of the muscular layer: non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC). Its aggressiveness is associated, inter alia, with genetic aberrations like losses of 1p, 6q, 9p, 9q and 13q; gain of 5p; or alterations in the p53 and p16 pathways. Moreover, there are reported metabolic disturbances connected with poor diagnosis-for example, enhanced aerobic glycolysis, gluconeogenesis or haem catabolism.Currently, the primary way of treatment method is transurethral resection of the bladder tumour (TURBT) with adjuvant Bacillus Calmette-Guérin (BCG) therapy for NMIBC or radical cystectomy for MIBC combined with chemotherapy or immunotherapy. However, intravesical BCG immunotherapy and immune checkpoint inhibitors are not efficient in every case, so appropriate biomarkers are needed in order to select the proper treatment options. It seems that the success of immunotherapy depends mainly on the tumour microenvironment (TME), which reflects the molecular disturbances in the tumour. TME consists of specific conditions like hypoxia or local acidosis and different populations of immune cells including tumour-infiltrating lymphocytes, natural killer cells, neutrophils and B lymphocytes, which are responsible for shaping the response against tumour neoantigens and crucial pathways like the PD-L1/PD-1 axis.In this review, we summarise holistically the impact of the immune system, genetic alterations and metabolic changes that are key factors in immunotherapy success. These findings should enable better understanding of the TME complexity in case of NMIBC and causes of failures of current therapies.


Assuntos
Neoplasias não Músculo Invasivas da Bexiga , Neoplasias da Bexiga Urinária , Humanos , Vacina BCG/uso terapêutico , Microambiente Tumoral , Neoplasias da Bexiga Urinária/patologia , Imunoterapia , Invasividade Neoplásica , Administração Intravesical , Adjuvantes Imunológicos
4.
Mol Psychiatry ; 27(3): 1839-1847, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34983929

RESUMO

The choroid plexus, a tissue responsible for producing cerebrospinal fluid, is found predominantly in the lateral and fourth ventricles of the brain. This highly vascularized and ciliated tissue is made up of specialized epithelial cells and capillary networks surrounded by connective tissue. Given the complex structure of the choroid plexus, this can potentially result in contamination during routine tissue dissection. Bulk and single-cell RNA sequencing studies, as well as genome-wide in situ hybridization experiments (Allen Brain Atlas), have identified several canonical markers of choroid plexus such as Ttr, Folr1, and Prlr. We used the Ttr gene as a marker to query the Gene Expression Omnibus database for transcriptome studies of brain tissue and identified at least some level of likely choroid contamination in numerous studies that could have potentially confounded data analysis and interpretation. We also analyzed transcriptomic datasets from human samples from Allen Brain Atlas and the Genotype-Tissue Expression (GTEx) database and found abundant choroid contamination, with regions in closer proximity to choroid more likely to be impacted such as hippocampus, cervical spinal cord, substantia nigra, hypothalamus, and amygdala. In addition, analysis of both the Allen Brain Atlas and GTEx datasets for differentially expressed genes between likely "high contamination" and "low contamination" groups revealed a clear enrichment of choroid plexus marker genes and gene ontology pathways characteristic of these ciliated choroid cells. Inclusion of these contaminated samples could result in biological misinterpretation or simply add to the statistical noise and mask true effects. We cannot assert that Ttr or other genes/proteins queried in targeted assays are artifacts from choroid contamination as some of these differentials may be due to true biological effects. However, for studies that have an unequal distribution of choroid contamination among groups, investigators may wish to remove contaminated samples from analyses or incorporate choroid marker gene expression into their statistical modeling. In addition, we suggest that a simple RT-qPCR or western blot for choroid markers would mitigate unintended choroid contamination for any experiment, but particularly for samples intended for more costly omic profiling. This study highlights an unexpected problem for neuroscientists, but it is also quite possible that unintended contamination of adjacent structures occurs during dissections for other tissues but has not been widely recognized.


Assuntos
Encéfalo , Plexo Corióideo , Biomarcadores/metabolismo , Encéfalo/metabolismo , Plexo Corióideo/metabolismo , Receptor 1 de Folato/metabolismo , Hipocampo/metabolismo , Humanos , Transcriptoma/genética
5.
Proc Natl Acad Sci U S A ; 114(33): E6962-E6971, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28701379

RESUMO

Alzheimer's disease (AD) is characterized by amyloid-ß (Aß) peptide deposition in brain parenchyma as plaques and in cerebral blood vessels as cerebral amyloid angiopathy (CAA). CAA deposition leads to several clinical complications, including intracerebral hemorrhage. The underlying molecular mechanisms that regulate plaque and CAA deposition in the vast majority of sporadic AD patients remain unclear. The clusterin (CLU) gene is genetically associated with AD and CLU has been shown to alter aggregation, toxicity, and blood-brain barrier transport of Aß, suggesting it might play a key role in regulating the balance between Aß deposition and clearance in both brain and blood vessels. Here, we investigated the effect of CLU on Aß pathology using the amyloid precursor protein/presenilin 1 (APP/PS1) mouse model of AD amyloidosis on a Clu+/+ or Clu-/- background. We found a marked decrease in plaque deposition in the brain parenchyma but an equally striking increase in CAA within the cerebrovasculature of APP/PS1;Clu-/- mice. Surprisingly, despite the several-fold increase in CAA levels, APP/PS1;Clu-/- mice had significantly less hemorrhage and inflammation. Mice lacking CLU had impaired clearance of Aß in vivo and exogenously added CLU significantly prevented Aß binding to isolated vessels ex vivo. These findings suggest that in the absence of CLU, Aß clearance shifts to perivascular drainage pathways, resulting in fewer parenchymal plaques but more CAA because of loss of CLU chaperone activity, complicating the potential therapeutic targeting of CLU for AD.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Angiopatia Amiloide Cerebral/metabolismo , Clusterina/deficiência , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Angiopatia Amiloide Cerebral/genética , Angiopatia Amiloide Cerebral/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Mutantes
6.
Nature ; 495(7442): 467-73, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23455423

RESUMO

Algorithms designed to identify canonical yeast prions predict that around 250 human proteins, including several RNA-binding proteins associated with neurodegenerative disease, harbour a distinctive prion-like domain (PrLD) enriched in uncharged polar amino acids and glycine. PrLDs in RNA-binding proteins are essential for the assembly of ribonucleoprotein granules. However, the interplay between human PrLD function and disease is not understood. Here we define pathogenic mutations in PrLDs of heterogeneous nuclear ribonucleoproteins (hnRNPs) A2B1 and A1 in families with inherited degeneration affecting muscle, brain, motor neuron and bone, and in one case of familial amyotrophic lateral sclerosis. Wild-type hnRNPA2 (the most abundant isoform of hnRNPA2B1) and hnRNPA1 show an intrinsic tendency to assemble into self-seeding fibrils, which is exacerbated by the disease mutations. Indeed, the pathogenic mutations strengthen a 'steric zipper' motif in the PrLD, which accelerates the formation of self-seeding fibrils that cross-seed polymerization of wild-type hnRNP. Notably, the disease mutations promote excess incorporation of hnRNPA2 and hnRNPA1 into stress granules and drive the formation of cytoplasmic inclusions in animal models that recapitulate the human pathology. Thus, dysregulated polymerization caused by a potent mutant steric zipper motif in a PrLD can initiate degenerative disease. Related proteins with PrLDs should therefore be considered candidates for initiating and perhaps propagating proteinopathies of muscle, brain, motor neuron and bone.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Demência Frontotemporal/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/química , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Distrofia Muscular do Cíngulo dos Membros/genética , Proteínas Mutantes/genética , Mutação/genética , Miosite de Corpos de Inclusão/genética , Osteíte Deformante/genética , Príons/química , Sequência de Aminoácidos , Esclerose Lateral Amiotrófica/metabolismo , Animais , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Células HeLa , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Humanos , Corpos de Inclusão/genética , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Masculino , Camundongos , Dados de Sequência Molecular , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Distrofia Muscular do Cíngulo dos Membros/patologia , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Miosite de Corpos de Inclusão/metabolismo , Miosite de Corpos de Inclusão/patologia , Osteíte Deformante/metabolismo , Osteíte Deformante/patologia , Fatores de Terminação de Peptídeos/química , Fatores de Terminação de Peptídeos/genética , Fatores de Terminação de Peptídeos/metabolismo , Príons/genética , Príons/metabolismo , Estrutura Terciária de Proteína/genética , RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
7.
Hum Mol Genet ; 25(16): 3467-3475, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27378688

RESUMO

Although abundant genetic and biochemical evidence strongly links Clusterin (CLU) to Alzheimer disease (AD) pathogenesis, the receptor for CLU within the adult brain is currently unknown. Using unbiased approaches, we identified Plexin A4 (PLXNA4) as a novel, high-affinity receptor for CLU in the adult brain. PLXNA4 protein expression was high in brain with much lower levels in peripheral organs. CLU protein levels were significantly elevated in the cerebrospinal fluid (CSF) of Plxna4-/- mice and, in humans, CSF levels of CLU were also associated with PLXNA4 genotype. Human AD brains had significantly increased the levels of CLU protein but decreased levels of PLXNA4 by ∼50%. To determine whether PLXNA4 levels influenced cognition, we analyzed the behaviour of Plxna4+/+, Plxna4+/-, and Plxna4-/- mice. In comparison to WT controls, both Plxna4+/- and Plxna4-/- mice were hyperactive in the open field assay while Plxna4-/- mice displayed a hyper-exploratory (low-anxiety phenotype) in the elevated plus maze. Importantly, both Plxna4+/- and Plxna4-/- mice displayed prominent deficits in learning and memory in the contextual fear-conditioning paradigm. Thus, even a 50% reduction in the level of PLXNA4 is sufficient to cause memory impairments, raising the possibility that memory problems seen in AD patients could be due to reductions in the level of PLXNA4. Both CLU and PLXNA4 have been genetically associated with AD risk and our data thus provide a direct relationship between two AD risk genes. Our data suggest that increasing the levels of PLXNA4 or targeting CLU-PLXNA4 interactions may have therapeutic value in AD.


Assuntos
Doença de Alzheimer/genética , Clusterina/genética , Mapas de Interação de Proteínas/genética , Receptores de Superfície Celular/genética , Doença de Alzheimer/fisiopatologia , Animais , Clusterina/biossíntese , Cognição/fisiologia , Regulação da Expressão Gênica , Predisposição Genética para Doença , Genótipo , Humanos , Memória/fisiologia , Camundongos , Camundongos Knockout , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/biossíntese , Fatores de Risco
8.
N Engl J Med ; 368(2): 117-27, 2013 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-23150934

RESUMO

BACKGROUND: Homozygous loss-of-function mutations in TREM2, encoding the triggering receptor expressed on myeloid cells 2 protein, have previously been associated with an autosomal recessive form of early-onset dementia. METHODS: We used genome, exome, and Sanger sequencing to analyze the genetic variability in TREM2 in a series of 1092 patients with Alzheimer's disease and 1107 controls (the discovery set). We then performed a meta-analysis on imputed data for the TREM2 variant rs75932628 (predicted to cause a R47H substitution) from three genomewide association studies of Alzheimer's disease and tested for the association of the variant with disease. We genotyped the R47H variant in an additional 1887 cases and 4061 controls. We then assayed the expression of TREM2 across different regions of the human brain and identified genes that are differentially expressed in a mouse model of Alzheimer's disease and in control mice. RESULTS: We found significantly more variants in exon 2 of TREM2 in patients with Alzheimer's disease than in controls in the discovery set (P=0.02). There were 22 variant alleles in 1092 patients with Alzheimer's disease and 5 variant alleles in 1107 controls (P<0.001). The most commonly associated variant, rs75932628 (encoding R47H), showed highly significant association with Alzheimer's disease (P<0.001). Meta-analysis of rs75932628 genotypes imputed from genomewide association studies confirmed this association (P=0.002), as did direct genotyping of an additional series of 1887 patients with Alzheimer's disease and 4061 controls (P<0.001). Trem2 expression differed between control mice and a mouse model of Alzheimer's disease. CONCLUSIONS: Heterozygous rare variants in TREM2 are associated with a significant increase in the risk of Alzheimer's disease. (Funded by Alzheimer's Research UK and others.).


Assuntos
Doença de Alzheimer/genética , Glicoproteínas de Membrana/genética , Mutação , Receptores Imunológicos/genética , Idoso , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Exoma/genética , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Técnicas de Genotipagem , Heterozigoto , Humanos , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos A , RNA Mensageiro/metabolismo , Receptores Imunológicos/metabolismo , Fatores de Risco , Análise de Sequência de DNA/métodos
9.
Int J Mol Sci ; 17(12)2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-27941701

RESUMO

Renal cell carcinoma (RCC) is one of the most common kidney malignancies. An upgraded comprehension of the molecular biology implicated in the development of cancer has stimulated an increase in research and development of innovative antitumor therapies. The aim of the study was to analyze the medical literature for hypertension and renal toxicities as the adverse events of the vascular endothelial growth factor (VEGF) signaling pathway inhibitor (anti-VEGF) therapy. Relevant studies were identified in PubMed and ClinicalTrials.gov databases. Eligible studies were phase III and IV prospective clinical trials, meta-analyses and retrospective studies that had described events of hypertension or nephrotoxicity for patients who received anti-VEGF therapy. A total of 48 studies were included in the systematic review. The incidence of any grade hypertension ranged from 17% to 49.6%. Proteinuria and increased creatinine levels were ascertained in 8% to 73% and 5% to 65.6% of patients, respectively. These adverse events are most often mild in severity but may sometimes lead to treatment discontinuation. Nephrotoxicity and hypertension are related to multiple mechanisms; however, one of the main disturbances in those patients is VEGF inhibition. There is a significant risk of developing hypertension and renal dysfunction among patients receiving anti-VEGF treatment; however, there is also some evidence that these side effects may be used as biomarkers of response to antiangiogenic agents.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Animais , Carcinoma de Células Renais/enzimologia , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/enzimologia , Neoplasias Renais/enzimologia
10.
Acta Neuropathol ; 130(2): 199-214, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25900293

RESUMO

Globular glial tauopathies (GGTs) are 4-repeat tauopathies neuropathologically characterized by tau-positive, globular glial inclusions, including both globular oligodendroglial inclusions and globular astrocytic inclusions. No mutations have been found in 25 of the 30 GGT cases reported in the literature who have been screened for mutations in microtubule associated protein tau (MAPT). In this report, six patients with GGT (four with subtype III and two with subtype I) were screened for MAPT mutations. They included 4 men and 2 women with a mean age at death of 73 years (55-83 years) and mean age at symptomatic onset of 66 years (50-77 years). Disease duration ranged from 5 to 14 years. All were homozygous for the MAPT H1 haplotype. Three patients had a positive family history of dementia, and a novel MAPT mutation (c.951G>C, p.K317N) was identified in one of them, a patient with subtype III. Recombinant tau protein bearing the lysine-to-asparagine substitution at amino acid residue 317 was used to assess functional significance of the variant on microtubule assembly and tau filament formation. Recombinant p.K317N tau had reduced ability to promote tubulin polymerization. Recombinant 3R and 4R tau bearing the p.K317N mutation showed decreased 3R tau and increased 4R tau filament assembly. These results strongly suggest that the p.K317N variant is pathogenic. Sequencing of MAPT should be considered in patients with GGT and a family history of dementia or movement disorder. Since several individuals in our series had a positive family history but no MAPT mutation, genetic factors other than MAPT may play a role in disease pathogenesis.


Assuntos
Mutação , Tauopatias/genética , Proteínas tau/genética , Idoso , Idoso de 80 Anos ou mais , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Microscopia Eletroquímica de Varredura , Microtúbulos/metabolismo , Pessoa de Meia-Idade , Linhagem , Polimerização , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tauopatias/metabolismo , Tauopatias/patologia , Tubulina (Proteína)/metabolismo , Proteínas tau/isolamento & purificação , Proteínas tau/metabolismo
11.
Brain ; 137(Pt 5): 1533-49, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24625695

RESUMO

Recent studies suggest that subcortical structures, including striatum, are vulnerable to amyloid-ß accumulation and other neuropathological features in familial Alzheimer's disease due to autosomal dominant mutations. We explored differences between familial and sporadic Alzheimer's disease that might shed light on their respective pathogenic mechanisms. To this end, we analysed 12 brain regions, including neocortical, limbic and subcortical areas, from post-mortem brains of familial Alzheimer's disease (n = 10; age at death: 50.0 ± 8.6 years) with mutations in amyloid precursor protein (APP) or presenilin 1 (PSEN1), sporadic Alzheimer's disease (n = 19; age at death: 84.7 ± 7.8 years), neurologically normal elderly without amyloid-ß accumulation (normal ageing; n = 13, age at death: 82.9 ± 10.8 years) and neurologically normal elderly with extensive cortical amyloid-ß deposits (pathological ageing; n = 15; age at death: 92.7 ± 5.9 years). The levels of amyloid-ß40, amyloid-ß42, APP, apolipoprotein E, the synaptic marker PSD95 (now known as DLG4), the astrocyte marker GFAP, other molecules related to amyloid-ß metabolism, and tau were determined by enzyme-linked immunosorbent assays. We observed that familial Alzheimer's disease had disproportionate amyloid-ß42 accumulation in subcortical areas compared with sporadic Alzheimer's disease, whereas sporadic Alzheimer's disease had disproportionate amyloid-ß42 accumulation in cortical areas compared to familial Alzheimer's disease. Compared with normal ageing, the levels of several proteins involved in amyloid-ß metabolism were significantly altered in both sporadic and familial Alzheimer's disease; however, such changes were not present in pathological ageing. Among molecules related to amyloid-ß metabolism, the regional distribution of PSD95 strongly correlated with the regional pattern of amyloid-ß42 accumulation in sporadic Alzheimer's disease and pathological ageing, whereas the regional distribution of APP as well as ß-C-terminal fragment of APP were strongly associated with the regional pattern of amyloid-ß42 accumulation in familial Alzheimer's disease. Apolipoprotein E and GFAP showed negative regional association with amyloid-ß (especially amyloid-ß40) accumulation in both sporadic and familial Alzheimer's disease. Familial Alzheimer's disease had greater striatal tau pathology than sporadic Alzheimer's disease. In a retrospective medical record review, atypical signs and symptoms were more frequent in familial Alzheimer's disease compared with sporadic Alzheimer's disease. These results suggest that disproportionate amyloid-ß42 accumulation in cortical areas in sporadic Alzheimer's disease may be mediated by synaptic processes, whereas disproportionate amyloid-ß42 accumulation in subcortical areas in familial Alzheimer's disease may be driven by APP and its processing. Region-specific amyloid-ß42 accumulation might account for differences in the relative amounts of tau pathology and clinical symptoms in familial and sporadic Alzheimer's disease.


Assuntos
Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/metabolismo , Sinapses/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/classificação , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Encéfalo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Emaranhados Neurofibrilares/patologia , Mudanças Depois da Morte , Presenilina-1/genética , Sinapses/patologia , Proteínas tau/metabolismo
12.
Hum Mutat ; 35(8): 964-71, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24796542

RESUMO

Three causal genes for idiopathic basal ganglia calcification (IBGC) have been identified. Most recently, mutations in PDGFRB, encoding a member of the platelet-derived growth factor receptor family type ß, and PDGFB, encoding PDGF-B, the specific ligand of PDGFRß, were found implicating the PDGF-B/PDGFRß pathway in abnormal brain calcification. In this study, we aimed to identify and study mutations in PDGFRB and PDGFB in a series of 26 patients from the Mayo Clinic Florida Brain Bank with moderate to severe basal ganglia calcification (BCG) of unknown etiology. No mutations in PDGFB were found. However, we identified one mutation in PDGFRB, p.R695C located in the tyrosine kinase domain, in one BGC patient. We further studied the function of p.R695C mutant PDGFRß and two previously reported mutants, p.L658P and p.R987W PDGFRß in cell culture. We show that, in response to PDGF-BB stimulation, the p.L658P mutation completely suppresses PDGFRß autophosphorylation, whereas the p.R695C mutation results in partial loss of autophosphorylation. For the p.R987W mutation, our data suggest a different mechanism involving reduced protein levels. These genetic and functional studies provide the first insight into the pathogenic mechanisms associated with PDGFRB mutations and provide further support for a pathogenic role of PDGFRB mutations in BGC.


Assuntos
Doenças dos Gânglios da Base/genética , Calcinose/genética , Mutação , Doenças Neurodegenerativas/genética , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-sis/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Idoso , Idoso de 80 Anos ou mais , Autopsia , Doenças dos Gânglios da Base/patologia , Becaplermina , Calcinose/patologia , Expressão Gênica , Testes Genéticos , Células HeLa , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/patologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-sis/farmacologia , Análise de Sequência de DNA , Transfecção
13.
medRxiv ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38260316

RESUMO

Dysfunction of the neurovascular unit stands as a significant pathological hallmark of Alzheimer's disease (AD) and age-related neurodegenerative diseases. Nevertheless, detecting vascular changes in the brain within bulk tissues has proven challenging, limiting our ability to characterize proteomic alterations from less abundant cell types. To address this challenge, we conducted quantitative proteomic analyses on both bulk brain tissues and cerebrovascular-enriched fractions from the same individuals, encompassing cognitively unimpaired control, progressive supranuclear palsy (PSP), and AD cases. Protein co-expression network analysis identified modules unique to the cerebrovascular fractions, specifically enriched with pericytes, endothelial cells, and smooth muscle cells. Many of these modules also exhibited significant correlations with amyloid plaques, cerebral amyloid angiopathy (CAA), and/or tau pathology in the brain. Notably, the protein products within AD genetic risk loci were found concentrated within modules unique to the vascular fractions, consistent with a role of cerebrovascular deficits in the etiology of AD. To prioritize peripheral AD biomarkers associated with vascular dysfunction, we assessed the overlap between differentially abundant proteins in AD cerebrospinal fluid (CSF) and plasma with a vascular-enriched network modules in the brain. This analysis highlighted matrisome proteins, SMOC1 and SMOC2, as being increased in CSF, plasma, and brain. Immunohistochemical analysis revealed SMOC1 deposition in both parenchymal plaques and CAA in the AD brain, whereas SMOC2 was predominantly localized to CAA. Collectively, these findings significantly enhance our understanding of the involvement of cerebrovascular abnormalities in AD, shedding light on potential biomarkers and molecular pathways associated with CAA and vascular dysfunction in neurodegenerative diseases.

14.
J Neurochem ; 126(6): 781-91, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23742080

RESUMO

Frontotemporal lobar degeneration (FTLD) is the second leading cause of dementia in individuals under age 65. In many patients, the predominant pathology includes neuronal cytoplasmic or intranuclear inclusions of ubiquitinated TAR DNA binding protein 43 (FTLD-TDP). Recently, a genome-wide association study identified the first FTLD-TDP genetic risk factor, in which variants in and around the TMEM106B gene (top SNP rs1990622) were significantly associated with FTLD-TDP risk. Intriguingly, the most significant association was in FTLD-TDP patients carrying progranulin (GRN) mutations. Here, we investigated to what extent the coding variant, rs3173615 (p.T185S) in linkage disequilibrium with rs1990622, affects progranulin protein (PGRN) biology and transmembrane protein 106 B (TMEM106B) regulation. First, we confirmed the association of TMEM106B variants with FTLD-TDP in a new cohort of GRN mutation carriers. We next generated and characterized a TMEM106B-specific antibody for investigation of this protein. Enzyme-linked immunoassay analysis of progranulin protein levels showed similar effects upon T185 and S185 TMEM106B over-expression. However, over-expression of T185 consistently led to higher TMEM106B protein levels than S185. Cycloheximide treatment experiments revealed that S185 degrades faster than T185 TMEM106B, potentially due to differences in N-glycosylation at residue N183. Together, our results provide a potential mechanism by which TMEM106B variants lead to differences in FTLD-TDP risk. We studied the p.T185S TMEM106B genetic variant previously implicated in frontotemporal dementia with TAR DNA binding protein 43 pathology caused by progranulin mutations. Our cell culture studies provide evidence that the protective S185 isoform is degraded more rapidly than T185 TMEM106B, potentially due to differences in glycosylation. These findings suggest that low TMEM106B levels might protect against FTLD-TDP in these patients.


Assuntos
Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Idoso , Western Blotting , Células Cultivadas , Estudos de Coortes , DNA Complementar/biossíntese , DNA Complementar/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Genótipo , Glicosilação , Células HeLa , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/genética , Isomerismo , Lisossomos/metabolismo , Masculino , Mutagênese/genética , Mutação/genética , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único/genética , Progranulinas , Reação em Cadeia da Polimerase em Tempo Real
15.
Cancers (Basel) ; 15(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38067231

RESUMO

INTRODUCTION: A tumor microenvironment plays an important role in bladder cancer development and in treatment response. PURPOSE: The aim of the study was to assess how the components of the microenvironment affect tumor recurrence and to find the potential biomarkers for immunotherapy in NMIBC. METHODS: The study group consisted of 55 patients with primary NMIBC. Immunohistochemistry was performed on sections of primary papillary urothelial carcinoma of the bladder. Cox proportional hazard multiple regression analysis was performed to characterize tumors with the highest probability of an unfavorable outcome. RESULTS: Multivariate analysis confirmed that the CD4 (p = 0.001), CD20 (p = 0.008) and PD-L1 expressed on tumor cells (p = 0.01) were independently associated with the risk of recurrence of bladder cancer. Patients with weak CD4+ cell infiltration (<4.6%) and severe CD20+ infiltration (>10%) belong to the group with a lower risk of recurrence. The cancer in this group also frequently recurs after 12 months (p = 0.0005). CONCLUSIONS: The evaluation of CD4+ and CD20+ cells in the tumor microenvironment, in addition to PD-L1 on tumor cells, facilitates the determination of a group of patients with a low risk of recurrence.

16.
Reproduction ; 143(6): 749-57, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22495889

RESUMO

The binding of capacitated spermatozoa to the egg's extracellular coat and induction of acrosome reaction are necessary for successful fertilization in mammals. Biogenesis of acrosome is complicated, and not all proteins involved in this process are known. In this study, we have cloned a novel mouse gene, Spaca7, that is expressed exclusively in the testes. During the postnatal development, transcripts of the gene could be detected at a very low level in 18-day-old mouse testes and at a higher level in 21-day-old mouse testes and later, which corresponds to an expansion of round spermatids. In the stably transfected PT67 cells, SPACA7 fused with EGFP was predominantly localized in the Golgi apparatus. In transgenic mouse testes, the fusion protein was found in acrosome (starting from the first stages of acrosome formation in late pachytene spermatocytes and finally in spermatozoa isolated from caput and cauda of epididymis). Confocal microscopy studies revealed an intra-acrosomal not membrane-bound localization of SPACA7/EGFP, which suggests that the protein can be released during acrosome reaction and involved in fertilization. Acrosomal localization of endogenous SPACA7 protein was also found in human spermatozoa.


Assuntos
Reação Acrossômica/genética , Proteínas de Plasma Seminal/isolamento & purificação , Animais , Células Cultivadas , Clonagem Molecular , Fertilização/genética , Fertilização/fisiologia , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Células NIH 3T3 , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/metabolismo , Espermatogênese/genética , Espermatogênese/fisiologia , Espermatozoides/química , Espermatozoides/metabolismo , Transfecção
17.
Biology (Basel) ; 11(2)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35205136

RESUMO

The tumor microenvironment is the space between healthy tissues and cancer cells, created by the extracellular matrix, blood vessels, infiltrating cells such as immune cells, and cancer-associated fibroblasts. These components constantly interact and influence each other, enabling cancer cells to survive and develop in the host organism. Accumulated intermediate metabolites favoring dysregulation and compensatory responses in the cell, called oncometabolites, provide a method of communication between cells and might also play a role in cancer growth. Here, we describe the changes in metabolic pathways that lead to accumulation of intermediate metabolites: lactate, glutamate, fumarate, and succinate in the tumor and their impact on the tumor microenvironment. These oncometabolites are not only waste products, but also link all types of cells involved in tumor survival and progression. Oncometabolites play a particularly important role in neoangiogenesis and in the infiltration of immune cells in cancer. Oncometabolites are also associated with a disrupted DNA damage response and make the tumor microenvironment more favorable for cell migration. The knowledge summarized in this article will allow for a better understanding of associations between therapeutic targets and oncometabolites, as well as the direct effects of these particles on the formation of the tumor microenvironment. In the future, targeting oncometabolites could improve treatment standards or represent a novel method for fighting cancer.

18.
Transplant Proc ; 54(4): 930-933, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35279304

RESUMO

Malignancy is the second cause of death in the dialyzed population. However, data on the prevalence of cancer are very scarce. Kidney transplantation improves quality of life, prolongs survival, and is cost-effective but bears some serious complications including malignancy. Therefore, active screening for cancer is of utmost importance. The aim of this study was to assess the prevalence of malignancy in dialyzed patients in relation to status on the on the waiting list and type of dialysis. This cross-sectional study was conducted in 108 hemodialyzed patients (mean age 65 years, 47 women) and 47 peritoneally dialyzed patients (mean age 51 years, 25 women). Among the population studied, 20 patients were actively waitlisted, including 14 peritoneal dialysis patients. Patients who had been active on the cadaver kidney waiting list and not listed did not differ in regard to sex, dialysis vintage, and causes of end-stage renal failure, but were significantly younger. Among hemodialysis patients, 24 of them had a history of malignancy and 10 in the peritoneal dialysis population. The most common were renal cell carcinoma in 6, breast cancer in 4, lung cancer in 3, prostate cancer in 3, hepatocellular cancer in 2, colorectal cancer in 2, esophageal cancer in 2, and others 14. In waitlisted patients, only 2 hemodialysis patients had a history of malignancy. Waitlisted patients represent a very selected and healthier dialyzed population. Malignancy has become a more common comorbidity in dialyzed patients, which may have important clinical implication regarding therapy. Guidelines for cancer screening in potential transplant recipients should be developed, as nowadays there are scarcity of data in this matter.


Assuntos
Carcinoma de Células Renais , Falência Renal Crônica , Neoplasias Renais , Transplante de Rim , Idoso , Carcinoma de Células Renais/complicações , Estudos Transversais , Feminino , Humanos , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/cirurgia , Neoplasias Renais/complicações , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida , Diálise Renal , Transplantados , Listas de Espera
19.
J Neurol Neurosurg Psychiatry ; 82(2): 196-203, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20562461

RESUMO

BACKGROUND: Frontotemporal dementia-amyotrophic lateral sclerosis (FTD-ALS) is a heritable form of FTD, but the gene(s) responsible for the majority of autosomal dominant FTD-ALS cases have yet to be found. Previous studies have identified a region on chromosome 9p that is associated with FTD and ALS. METHODS: The authors report the clinical, volumetric MRI, neuropathological and genetic features of a new chromosome 9p-linked FTD-ALS family, VSM-20. RESULTS: Ten members of family VSM-20 displayed heterogeneous clinical phenotypes of isolated behavioural-variant FTD (bvFTD), ALS or a combination of the two. Parkinsonism was common, with one individual presenting with a corticobasal syndrome. Analysis of structural MRI scans from five affected family members revealed grey- and white-matter loss that was most prominent in the frontal lobes, with mild parietal and occipital lobe atrophy, but less temporal lobe atrophy than in 10 severity-matched sporadic bvFTD cases. Autopsy in three family members showed a consistent and unique subtype of FTLD-TDP pathology. Genome-wide linkage analysis conclusively linked family VSM-20 to a 28.3 cM region between D9S1808 and D9S251 on chromosome 9p, reducing the published minimal linked region to a 3.7 Mb interval. Genomic sequencing and expression analysis failed to identify mutations in the 10 known and predicted genes within this candidate region, suggesting that next-generation sequencing may be needed to determine the mutational mechanism associated with chromosome 9p-linked FTD-ALS. CONCLUSIONS: Family VSM-20 significantly reduces the region linked to FTD-ALS on chromosome 9p. A distinct pattern of brain atrophy and neuropathological findings may help to identify other families with FTD-ALS caused by this genetic abnormality.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Cromossomos Humanos Par 9/genética , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Adulto , Esclerose Lateral Amiotrófica/complicações , Autopsia , Encéfalo/patologia , Análise Mutacional de DNA , Família , Feminino , Demência Frontotemporal/complicações , Ligação Genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Haplótipos , Humanos , Imuno-Histoquímica , Escore Lod , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/genética , Linhagem
20.
Hum Mutat ; 31(5): E1377-89, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20232451

RESUMO

Mutations in the gene encoding fused in sarcoma (FUS) were recently identified as a novel cause of amyotrophic lateral sclerosis (ALS), emphasizing the genetic heterogeneity of ALS. We sequenced the genes encoding superoxide dismutase (SOD1), TAR DNA-binding protein 43 (TARDBP) and FUS in 99 sporadic and 17 familial ALS patients ascertained at Mayo Clinic. We identified two novel mutations in FUS in two out of 99 (2.0%) sporadic ALS patients and established the de novo occurrence of one FUS mutation. In familial patients, we identified three (17.6%) SOD1 mutations, while FUS and TARDBP mutations were excluded. The de novo FUS mutation (g.10747A>G; IVS13-2A>G) affects the splice-acceptor site of FUS intron 13 and was shown to induce skipping of FUS exon 14 leading to the C-terminal truncation of FUS (p.G466VfsX14). Subcellular localization studies showed a dramatic increase in the cytoplasmic localization of FUS and a reduction of normal nuclear expression in cells transfected with truncated compared to wild-type FUS. We further identified a novel in-frame insertion/deletion mutation in FUS exon 12 (p.S402_P411delinsGGGG) which is predicted to expand a conserved poly-glycine motif. Our findings extend the mutation spectrum in FUS leading to ALS and describe the first de novo mutation in FUS.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteína FUS de Ligação a RNA/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , Proteína FUS de Ligação a RNA/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Adulto Jovem
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