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1.
Front Mol Neurosci ; 16: 1215637, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520429

RESUMO

Introduction: Vascular dementia (VaD) is one of the most common causes of dementia among the elderly. Despite this, the molecular basis of VaD remains poorly characterized when compared to other age-related dementias. Pervasive cerebral elevations of urea have recently been reported in several dementias; however, a similar analysis was not yet available for VaD. Methods: Here, we utilized ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) to measure urea levels from seven brain regions in post-mortem tissue from cases of VaD (n = 10) and controls (n = 8/9). Brain-urea measurements from our previous investigations of several dementias were also used to generate comparisons with VaD. Results: Elevated urea levels ranging from 2.2- to 2.4-fold-change in VaD cases were identified in six out of the seven regions analysed, which are similar in magnitude to those observed in uremic encephalopathy. Fold-elevation of urea was highest in the basal ganglia and hippocampus (2.4-fold-change), consistent with the observation that these regions are severely affected in VaD. Discussion: Taken together, these data not only describe a multiregional elevation of brain-urea levels in VaD but also imply the existence of a common urea-mediated disease mechanism that is now known to be present in at least four of the main age-related dementias.

2.
NPJ Parkinsons Dis ; 9(1): 66, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081022

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative diseases, most commonly characterised by motor dysfunction, but also with a high prevalence of cognitive decline in the decades following diagnosis-a condition known as Parkinson's disease dementia (PDD). Although several metabolic disruptions have been identified in PD, there has yet to be a multi-regional analysis of multiple metabolites conducted in PDD brains. This discovery study attempts to address this gap in knowledge. A semi-targeted liquid chromatography-mass spectrometry analysis of nine neuropathologically-confirmed PDD cases vs nine controls was performed, looking at nine different brain regions, including the cingulate gyrus, cerebellum, hippocampus, motor cortex, medulla, middle temporal gyrus, pons, substantia nigra and primary visual cortex. Case-control differences were determined by multiple t-tests followed by 10% FDR correction. Of 64 identified analytes, 49 were found to be altered in at least one region of the PDD brain. These included metabolites from several pathways, including glucose and purine metabolism and the TCA cycle, with widespread increases in fructose, inosine and ribose-5-phosphate, as well as decreases in proline, serine and deoxyguanosine. Higher numbers of alterations were observed in PDD brain regions that are affected during earlier α-synuclein Braak stages-with the exception of the cerebellum, which showed an unexpectedly high number of metabolic changes. PDD brains show multi-regional alterations in glucose and purine metabolic pathways that reflect the progression of α-synuclein Braak staging. Unexpectedly, the cerebellum also shows a high number of metabolic changes.

3.
Schizophr Bull ; 49(4): 893-902, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-36916850

RESUMO

BACKGROUND AND HYPOTHESIS: Treatment response to specific antipsychotic medications is difficult to predict on clinical grounds alone. The current study hypothesizes that the baseline complement pathway activity predicts the treatment response and investigates the relationship between baseline plasma biomarkers with treatment response to antipsychotic medications. STUDY DESIGN: Baseline plasma samples were collected from first episode of psychosis patients (n = 243) from a multi-center clinical trial. The participants were treated with amisulpride for 4 weeks. Levels of complement and coagulation proteins at baseline were measured using both data-dependent and data-independent mass spectrometry approaches. The primary outcome was remission status at 4 weeks and the secondary outcomes included change in psychotic and functional symptoms over the period of treatment. In addition, immunoassays were performed at baseline for complement C1R, as well as for activation markers C4a and sC5b-9. STUDY RESULTS: The plasma level of complement variant C4A was significantly associated with remission at 4 weeks. Moreover, higher levels of several complement and coagulation pathway proteins were associated with a reduction in psychotic symptoms and an improvement in functioning. Immunoassays showed an association of baseline levels of C1R and C4a as well as complement activation marker sC5b-9 levels with treatment response. CONCLUSION: The results demonstrated that the response to antipsychotic treatment might be related to pre-treatment levels of plasma complement and coagulation pathway proteins. This is consistent with independent evidence associating immune dysfunction with the pathophysiology of psychosis. Moreover, these results inform the development of novel therapeutic approaches that target the complement system for psychosis.


Assuntos
Antipsicóticos , Transtornos Psicóticos , Humanos , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Transtornos Psicóticos/diagnóstico
4.
Anal Methods ; 15(14): 1797-1801, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942637

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease. Tofacitinib is a Janus Kinase inhibitor licensed for the treatment of RA that, unlike biologic anti-rheumatic drugs, is administered orally, but studies of long-term treatment adherence rates are lacking. The measurement of adherence, however, is challenging and there is currently no gold standard test for adherence. Here, we developed a novel HPLC MS/MS assay for the quantification of tofacitinib. The assay demonstrated a LLOQ for tofacitinib of 0.1 ng ml-1, within run accuracy was 81-85% at LLOQ and 91-107% at all other levels. To investigate the ability of the assay to detect adherence, tofacitinib was measured in a random selection of serum samples (n = 10) of tofacitinib treated RA patients who self-reported adherent behaviour. The assay measured tofacitinib in all samples above the LLOQ demonstrating the potential of the assay to sensitively measure biochemical adherence in real-world patient samples. This method for detection of adherence has the potential to be a more objective measure that could be used in the future in the clinic but will require further studies to explore factors that may influence measurement of drug levels, such as clinical characteristics of patients.


Assuntos
Antirreumáticos , Artrite Reumatoide , Humanos , Espectrometria de Massas em Tandem , Pirróis , Antirreumáticos/efeitos adversos , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/tratamento farmacológico
5.
Methods Mol Biol ; 2426: 141-162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36308689

RESUMO

seaMass is an R package for protein-level quantification, normalization, and differential expression analysis of proteomics mass spectrometry data after peptide identification, protein grouping, and feature-level quantification. Using the concept of a blocked experimental design, seaMass can analyze all common discovery proteomics paradigms, including label-free (e.g., Waters Progenesis input), SILAC (e.g., MaxQuant input), isotope labelling (e.g., SCIEX ProteinPilot iTraq and Thermo ProteomeDiscoverer TMT input), and data-independent acquisition (e.g., OpenSWATH-PyProphet input), and is able to scale to study with hundreds of assays or more. By utilizing hierarchical Bayesian modelling, seaMass assesses the quantification reliability of each feature and peptide across assays so that only those in consensus influence the resulting protein group quantification strongly. Similarly, unexplained variation in each individual assay is captured, providing both a metric for quality control and automatic down-weighting of suspect assays. To achieve this, each protein group-level quantification outputted by seaMass is accompanied by the standard deviation of its posterior uncertainty. Moreover, seaMass integrates a flexible differential expression analysis subsystem with false discovery rate control based on the popular MCMCglmm package for Bayesian mixed-effects modelling, and also provides uncertainty-aware principal components analysis. We provide a description for using seaMass to perform an end-to-end analysis using a real dataset associated with a published clinical proteomics study.


Assuntos
Proteínas , Proteômica , Proteômica/métodos , Incerteza , Reprodutibilidade dos Testes , Teorema de Bayes , Peptídeos , Proteoma/metabolismo
6.
Front Immunol ; 13: 1032331, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330526

RESUMO

The SARS-CoV-2 virus continues to cause significant morbidity and mortality worldwide from COVID-19. One of the major challenges of patient management is the broad range of symptoms observed. While the majority of individuals experience relatively mild disease, a significant minority of patients require hospitalisation, with COVID-19 still proving fatal for some. As such, there remains a desperate need to better understand what drives this severe disease, both in terms of the underlying biology, but also to potentially predict at diagnosis which patients are likely to require further interventions, thus enabling better outcomes for both patients and healthcare systems. Several lines of evidence have pointed to dysregulation of the complement cascade as a major factor in severe COVID-19 outcomes. How this is underpinned mechanistically is not known. Here, we have focussed on the role of the soluble complement regulators Complement Factor H (FH), its splice variant Factor H-like 1 (FHL-1) and five Factor H-Related proteins (FHR1-5). Using a targeted mass spectrometry approach, we quantified these proteins in a cohort of 188 plasma samples from controls and SARS-CoV-2 patients taken at diagnosis. This analysis revealed significant elevations in all FHR proteins, but not FH, in patients with more severe disease, particularly FHR2 and FHR5 (FHR2: 1.97-fold, p<0.0001; FHR5: 2.4-fold, p<0.0001). Furthermore, for a subset of 77 SARS-CoV-2 +ve patients we also analysed time course samples taken approximately 28 days post-diagnosis. Here, we see complement regulator levels drop in all individuals with asymptomatic or mild disease, but regulators remain high in those with more severe outcomes, with elevations in FHR2 over baseline levels in this group. These data support the hypothesis that elevation of circulating levels of the FHR family of proteins could predict disease severity in COVID-19 patients, and that the duration of elevation (or lack of immune activation resolution) may be partly responsible for driving poor outcomes in COVID-19.


Assuntos
COVID-19 , Fator H do Complemento , Humanos , SARS-CoV-2 , Ativação do Complemento , Fatores Imunológicos
7.
EBioMedicine ; 86: 104317, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36335667

RESUMO

BACKGROUND: Type-2 diabetes (T2D) is characterized by chronic hyperglycaemia and glucose-evoked organ damage, and displays systemic copper overload, elevated risk of impaired cognitive function, and epidemiological links to sporadic Alzheimer's disease (sAD). Contrastingly, sAD exhibits impaired cerebral-glucose uptake, elevation of cerebral glucose but not blood glucose levels, and widespread cerebral-copper deficiency. We hypothesized that sAD-like brain-metal perturbations would occur in T2D. METHODS: We measured nine essential elements in an observational case-control study of T2D without dementia (6 cases and 6 controls) in four brain regions and compared the results with those from our study of brain metals in sAD (9 cases and 9 controls), which employed equivalent analytical methodology. We evaluated intergroup differences by supervised and unsupervised multivariate-statistical approaches to contrast between T2D cases and controls, and to compare them with cerebral-metal patterns in sAD. FINDINGS: Unexpectedly, we found that hippocampal-copper levels in T2D were markedly elevated compared with controls (P = 0.005 and 0.007 by Welch's t-test in two technical-replicate experiments), to levels similar to those in cases of untreated Wilson's disease (WD), wherein elevated cerebral copper causes neurodegeneration. By contrast, hippocampal-copper levels in sAD were markedly deficient. Multivariate analysis identified marked differences in patterns of essential metals between hippocampal datasets from cases of T2D and of sAD. INTERPRETATION: Elevated hippocampal copper could contribute to the pathogenesis of cerebral neurodegeneration and cognitive impairment in T2D, similar to known impacts of elevated brain copper in WD. Therapeutic approaches with copper-lowering agents similar to those currently employed in pharmacotherapy of WD, may also be applicable in patients with T2D and impaired cognitive function. Further studies will be required to replicate and extend these findings and to investigate their potential therapeutic implications. FUNDING: In Acknowledgments, includes Endocore Research Trust; Lee Trust; Oakley Mental Health Research Foundation; Ministry of Business, Innovation & Employment; The Universities of Auckland and Manchester, and others.


Assuntos
Diabetes Mellitus Tipo 2 , Degeneração Hepatolenticular , Humanos , Cobre , Estudos de Casos e Controles , Degeneração Hepatolenticular/patologia , Metais , Hipocampo/patologia , Glucose
8.
Front Aging Neurosci ; 14: 926463, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923550

RESUMO

Vascular dementia (VaD) is the second most common cause of cognitive impairment amongst the elderly. However, there are no known disease-modifying therapies for VaD, probably due to incomplete understanding of the molecular basis of the disease. Despite the complex etiology of neurodegenerative conditions, a growing body of research now suggests the potential involvement of metal dyshomeostasis in the pathogenesis of several of the age-related dementias. However, by comparison, there remains little research investigating brain metal levels in VaD. In order to shed light on the possible involvement of metal dyshomeostasis in VaD, we employed inductively coupled plasma-mass spectrometry to quantify the levels of essential metals in post-mortem VaD brain tissue (n = 10) and age-/sex-matched controls (n = 10) from seven brain regions. We found novel evidence for elevated wet-weight cerebral sodium levels in VaD brain tissue in six out of the seven regions analyzed. Decreased cerebral-potassium levels as well as increased Na/K ratios (consistent with high tissue sodium and low potassium levels) were also observed in several brain regions. These data suggest that reduced Na+/K+-exchanging ATPase (EC 7.2.2.13) activity could contribute to the contrasting changes in sodium and potassium measured here.

9.
Front Aging Neurosci ; 14: 893159, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754968

RESUMO

Sporadic Alzheimer's disease (sAD) is the commonest cause of age-related neurodegeneration and dementia globally, and a leading cause of premature disability and death. To date, the quest for a disease-modifying therapy for sAD has failed, probably reflecting our incomplete understanding of aetiology and pathogenesis. Drugs that target aggregated Aß/tau are ineffective, and metabolic defects are now considered to play substantive roles in sAD pathobiology. We tested the hypothesis that the recently identified, pervasive cerebral deficiency of pantothenate (vitamin B5) in sAD, might undermine brain energy metabolism by impairing levels of tricarboxylic acid (TCA)-cycle enzymes and enzyme complexes, some of which require the pantothenate-derived cofactor, coenzyme A (CoA) for their normal functioning. We applied proteomics to measure levels of the multi-subunit TCA-cycle enzymes and their cytoplasmic homologues. We analysed six functionally distinct brain regions from nine sAD cases and nine controls, measuring 33 cerebral proteins that comprise the nine enzymes of the mitochondrial-TCA cycle. Remarkably, we found widespread perturbations affecting only two multi-subunit enzymes and two enzyme complexes, whose function is modulated, directly or indirectly by CoA: pyruvate dehydrogenase complex, isocitrate dehydrogenase, 2-oxoglutarate dehydrogenase complex, and succinyl-CoA synthetase. The sAD cases we studied here displayed widespread deficiency of pantothenate, the obligatory precursor of CoA. Therefore, deficient cerebral pantothenate can damage brain-energy metabolism in sAD, at least in part through impairing levels of these four mitochondrial-TCA-cycle enzymes.

10.
Proc Natl Acad Sci U S A ; 119(20): e2118510119, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35561216

RESUMO

Age-related macular degeneration (AMD) is a leading cause of visual loss. It has a strong genetic basis, and common haplotypes on chromosome (Chr) 1 (CFH Y402H variant) and on Chr10 (near HTRA1/ARMS2) contribute the most risk. Little is known about the early molecular and cellular processes in AMD, and we hypothesized that analyzing submacular tissue from older donors with genetic risk but without clinical features of AMD would provide biological insights. Therefore, we used mass spectrometry­based quantitative proteomics to compare the proteins in human submacular stromal tissue punches from donors who were homozygous for high-risk alleles at either Chr1 or Chr10 with those from donors who had protective haplotypes at these loci, all without clinical features of AMD. Additional comparisons were made with tissue from donors who were homozygous for high-risk Chr1 alleles and had early AMD. The Chr1 and Chr10 risk groups shared common changes compared with the low-risk group, particularly increased levels of mast cell­specific proteases, including tryptase, chymase, and carboxypeptidase A3. Histological analyses of submacular tissue from donors with genetic risk of AMD but without clinical features of AMD and from donors with Chr1 risk and AMD demonstrated increased mast cells, particularly the tryptase-positive/chymase-negative cells variety, along with increased levels of denatured collagen compared with tissue from low­genetic risk donors. We conclude that increased mast cell infiltration of the inner choroid, degranulation, and subsequent extracellular matrix remodeling are early events in AMD pathogenesis and represent a unifying mechanistic link between Chr1- and Chr10-mediated AMD.


Assuntos
Cromossomos Humanos Par 10 , Cromossomos Humanos Par 1 , Degeneração Macular , Mastócitos , Peptídeo Hidrolases , Alelos , Corioide/enzimologia , Corioide/patologia , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 10/genética , Humanos , Degeneração Macular/genética , Degeneração Macular/patologia , Mastócitos/patologia , Peptídeo Hidrolases/genética , Proteômica , Risco , Triptases/metabolismo
11.
Methods Mol Biol ; 2490: 157-177, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35486245

RESUMO

In this methods chapter, we describe the use of isobaric tags for relative and absolute quantification (iTRAQ) for the differential expression analysis of global proteins between embryonic stem cell samples. This protocol describes how proteins are collected from cell culture, digested and prepared so that peptides are labeled with these isobaric tags. Labeled digests are pooled, fractionated offline, and quantified using liquid chromatography-mass spectrometry (LC-MS). This offline fractionation allows for a greater separation and thus increased identification/quantification of peptides. This combined method enables large-scale, deep penetration into the proteome of embryonic stem cells. During quantification, the relative intensities of label-derived reporter ions represent the relative amount of peptide in each sample. Using search algorithms that integrate the generated data for the identified and quantified peptides allows the relative quantification of proteins in the samples. The isobaric tags can be used in a 4 or 8 multiplexed manner; however, using an 8-plex experimental setup allows for the simultaneous analysis of biological and technical replicates within the same mass spectrometry run, thus minimizing experimental variation and increasing the confidence in any identified expression differences.


Assuntos
Proteômica , Espectrometria de Massas em Tandem , Cromatografia Líquida , Células-Tronco Embrionárias/metabolismo , Peptídeos/química , Proteoma/metabolismo , Proteômica/métodos , Espectrometria de Massas em Tandem/métodos
12.
Front Aging Neurosci ; 14: 822787, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35153731

RESUMO

Vascular dementia (VaD) is thought to be the second most common cause of age-related dementia amongst the elderly. However, at present, there are no available disease-modifying therapies for VaD, probably due to insufficient understanding about the molecular basis of the disease. While the notion of metal dyshomeostasis in various age-related dementias has gained considerable attention in recent years, there remains little comparable investigation in VaD. To address this evident gap, we employed inductively coupled-plasma mass spectrometry to measure the concentrations of nine essential metals in both dry- and wet-weight hippocampal post-mortem tissue from cases with VaD (n = 10) and age-/sex-matched controls (n = 10). We also applied principal component analysis to compare the metallomic pattern of VaD in the hippocampus with our previous hippocampal metal datasets for Alzheimer's disease, Huntington's disease, Parkinson's disease, and type-2 diabetes, which had been measured using the same methodology. We found substantive novel evidence for elevated hippocampal Na levels and Na/K ratios in both wet- and dry-weight analyses, whereas decreased K levels were present only in wet tissue. Multivariate analysis revealed no distinguishable hippocampal differences in metal-evoked patterns between these dementia-causing diseases in this study. Contrasting levels of Na and K in hippocampal VaD tissue may suggest dysfunction of the Na+/K+-exchanging ATPase (EC 7.2.2.13), possibly stemming from deficient metabolic energy (ATP) generation. These findings therefore highlight the potential diagnostic importance of cerebral sodium measurement in VaD patients.

14.
Exp Eye Res ; 215: 108908, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34954204

RESUMO

Opticin is an extracellular glycoprotein present in the vitreous. Its antiangiogenic properties offer the potential for therapeutic intervention in conditions such as proliferative diabetic retinopathy and retinopathy of prematurity. Here, we investigated the hypothesis that intravitreal administration of recombinant human opticin can safely protect against the development of pathological angiogenesis and promote its regression. We generated and purified recombinant human opticin and investigated its impact on the development and regression of pathological retinal neovascularization following intravitreal administration in murine oxygen-induced retinopathy. We also investigated its effect on normal retinal vascular development and function, following intravitreal injection in neonatal mice, by histological examination and electroretinography. In oxygen-induced retinopathy, intravitreal administration of human recombinant opticin protected against the development of retinal neovascularization to similar extent as aflibercept, which targets VEGF. Opticin also accelerated regression of established retinal neovascularization, though the effect at 18 h was less than that of aflibercept. Intravitreal administration of human recombinant opticin in neonatal mice caused no detectable perturbation of subsequent retinal vascular development or function. In summary we found that intraocular administration of recombinant human opticin protects against the development of pathological angiogenesis in mice and promotes its regression.


Assuntos
Hiperóxia , Neovascularização Retiniana , Retinopatia da Prematuridade , Animais , Modelos Animais de Doenças , Humanos , Hiperóxia/complicações , Recém-Nascido , Injeções Intravítreas , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica , Oxigênio/toxicidade , Neovascularização Retiniana/tratamento farmacológico , Retinopatia da Prematuridade/tratamento farmacológico , Retinopatia da Prematuridade/prevenção & controle
15.
Sci Data ; 8(1): 312, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34862388

RESUMO

Mass spectrometry (MS)-based proteomics is a powerful tool to explore pathogenic changes of a disease in an unbiased manner and has been used extensively in Alzheimer disease (AD) research. Here, by performing a meta-analysis of high-quality proteomic studies, we address which pathological changes are observed consistently and therefore most likely are of great importance for AD pathogenesis. We retrieved datasets, comprising a total of 21,588 distinct proteins identified across 857 postmortem human samples, from ten studies using labeled or label-free MS approaches. Our meta-analysis findings showed significant alterations of 757 and 1,195 proteins in AD in the labeled and label-free datasets, respectively. Only 33 proteins, some of which were associated with synaptic signaling, had the same directional change across the individual studies. However, despite alterations in individual proteins being different between the labeled and the label-free datasets, several pathways related to synaptic signaling, oxidative phosphorylation, immune response and extracellular matrix were commonly dysregulated in AD. These pathways represent robust changes in the human AD brain and warrant further investigation.


Assuntos
Doença de Alzheimer/metabolismo , Proteoma/metabolismo , Matriz Extracelular , Humanos , Imunidade , Fosforilação Oxidativa , Proteômica/métodos , Transmissão Sináptica
16.
Front Mol Neurosci ; 14: 711396, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34751215

RESUMO

Widespread elevations in brain urea have, in recent years, been reported in certain types of age-related dementia, notably Alzheimer's disease (AD) and Huntington's disease (HD). Urea increases in these diseases are substantive, and approximate in magnitude to levels present in uraemic encephalopathy. In AD and HD, elevated urea levels are widespread, and not only in regions heavily affected by neurodegeneration. However, measurements of brain urea have not hitherto been reported in Parkinson's disease dementia (PDD), a condition which shares neuropathological and symptomatic overlap with both AD and HD. Here we report measurements of tissue urea from nine neuropathologically confirmed regions of the brain in PDD and post-mortem delay (PMD)-matched controls, in regions including the cerebellum, motor cortex (MCX), sensory cortex, hippocampus (HP), substantia nigra (SN), middle temporal gyrus (MTG), medulla oblongata (MED), cingulate gyrus, and pons, by applying ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Urea concentrations were found to be substantively elevated in all nine regions, with average increases of 3-4-fold. Urea concentrations were remarkably consistent across regions in both cases and controls, with no clear distinction between regions heavily affected or less severely affected by neuronal loss in PDD. These urea elevations mirror those found in uraemic encephalopathy, where equivalent levels are generally considered to be pathogenic, and those previously reported in AD and HD. Increased urea is a widespread metabolic perturbation in brain metabolism common to PDD, AD, and HD, at levels equal to those seen in uremic encephalopathy. This presents a novel pathogenic mechanism in PDD, which is shared with two other neurodegenerative diseases.

17.
Metabolites ; 11(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34564384

RESUMO

Pantothenic acid (vitamin B5) is an essential trace nutrient required for the synthesis of coenzyme A (CoA). It has previously been shown that pantothenic acid is significantly decreased in multiple brain regions in both Alzheimer's disease (ADD) and Huntington's disease (HD). The current investigation aimed to determine whether similar changes are also present in cases of Parkinson's disease dementia (PDD), another age-related neurodegenerative condition, and whether such perturbations might occur in similar regions in these apparently different diseases. Brain tissue was obtained from nine confirmed cases of PDD and nine controls with a post-mortem delay of 26 h or less. Tissues were acquired from nine regions that show high, moderate, or low levels of neurodegeneration in PDD: the cerebellum, motor cortex, primary visual cortex, hippocampus, substantia nigra, middle temporal gyrus, medulla oblongata, cingulate gyrus, and pons. A targeted ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) approach was used to quantify pantothenic acid in these tissues. Pantothenic acid was significantly decreased in the cerebellum (p = 0.008), substantia nigra (p = 0.02), and medulla (p = 0.008) of PDD cases. These findings mirror the significant decreases in the cerebellum of both ADD and HD cases, as well as the substantia nigra, putamen, middle frontal gyrus, and entorhinal cortex of HD cases, and motor cortex, primary visual cortex, hippocampus, middle temporal gyrus, cingulate gyrus, and entorhinal cortex of ADD cases. Taken together, these observations indicate a common but regionally selective disruption of pantothenic acid levels across PDD, ADD, and HD.

18.
Clin Cancer Res ; 27(23): 6514-6528, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34479957

RESUMO

PURPOSE: Glioblastoma (GBM) is an incurable primary brain tumor that has not benefited from immunotherapy to date. More than 90% of GBM expresses the tryptophan (Trp) metabolic enzyme, indoleamine 2,3-dioxygenase 1 (IDO). This observation supported the historical hypothesis that IDO suppresses the antitumor immune response solely through a mechanism that requires intratumoral Trp depletion. However, recent findings led us to investigate the alternative hypothesis that IDO suppresses the anti-GBM immune response independent of its association with Trp metabolism. EXPERIMENTAL DESIGN: IDO-deficient GBM cell lines reconstituted with IDO wild-type or IDO enzyme-null cDNA were created and validated in vitro and in vivo. Microarray analysis was conducted to search for genes that IDO regulates, followed by the analysis of human GBM cell lines, patient GBM and plasma, and The Cancer Genome Atlas (TCGA) database. Ex vivo cell coculture assays, syngeneic and humanized mouse GBM models, were used to test the alternative hypothesis. RESULTS: Nonenzymic tumor cell IDO activity decreased the survival of experimental animals and increased the expression of complement factor H (CFH) and its isoform, factor H like protein 1 (FHL-1) in human GBM. Tumor cell IDO increased CFH and FHL-1 expression independent of Trp metabolism. Increased intratumoral CFH and FHL-1 levels were associated with poorer survival among patients with glioma. Similar to IDO effects, GBM cell FHL-1 expression increased intratumoral regulatory T cells (Treg) and myeloid-derived suppressor cells while it decreased overall survival in mice with GBM. CONCLUSIONS: Our study reveals a nonmetabolic IDO-mediated enhancement of CFH expression and provides a new therapeutic target for patients with GBM.


Assuntos
Glioblastoma , Glioma , Animais , Glioma/tratamento farmacológico , Humanos , Terapia de Imunossupressão , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Camundongos , Triptofano/farmacologia
19.
Elife ; 102021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34350828

RESUMO

The circadian clock component NR1D1 (REVERBα) is considered a dominant regulator of lipid metabolism, with global Nr1d1 deletion driving dysregulation of white adipose tissue (WAT) lipogenesis and obesity. However, a similar phenotype is not observed under adipocyte-selective deletion (Nr1d1Flox2-6:AdipoqCre), and transcriptional profiling demonstrates that, under basal conditions, direct targets of NR1D1 regulation are limited, and include the circadian clock and collagen dynamics. Under high-fat diet (HFD) feeding, Nr1d1Flox2-6:AdipoqCre mice do manifest profound obesity, yet without the accompanying WAT inflammation and fibrosis exhibited by controls. Integration of the WAT NR1D1 cistrome with differential gene expression reveals broad control of metabolic processes by NR1D1 which is unmasked in the obese state. Adipocyte NR1D1 does not drive an anticipatory daily rhythm in WAT lipogenesis, but rather modulates WAT activity in response to alterations in metabolic state. Importantly, NR1D1 action in adipocytes is critical to the development of obesity-related WAT pathology and insulin resistance.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Obesidade/genética , Animais , Metabolismo Energético , Deleção de Genes , Metabolismo dos Lipídeos , Masculino , Camundongos , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Obesidade/metabolismo
20.
J Huntingtons Dis ; 10(4): 423-434, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34420978

RESUMO

BACKGROUND: The pathological mechanism of cellular dysfunction and death in Huntington's disease (HD) is not well defined. Our transgenic HD sheep model (OVT73) was generated to investigate these mechanisms and for therapeutic testing. One particular cohort of animals has undergone focused investigation resulting in a large interrelated multi-omic dataset, with statistically significant changes observed comparing OVT73 and control 'omic' profiles and reported in literature. OBJECTIVE: Here we make this dataset publicly available for the advancement of HD pathogenic mechanism discovery. METHODS: To enable investigation in a user-friendly format, we integrated seven multi-omic datasets from a cohort of 5-year-old OVT73 (n = 6) and control (n = 6) sheep into a single database utilising the programming language R. It includes high-throughput transcriptomic, metabolomic and proteomic data from blood, brain, and other tissues. RESULTS: We present the 'multi-omic' HD sheep database as a queryable web-based platform that can be used by the wider HD research community (https://hdsheep.cer.auckland.ac.nz/). The database is supported with a suite of simple automated statistical analysis functions for rapid exploratory analyses. We present examples of its use that validates the integrity relative to results previously reported. The data may also be downloaded for user determined analysis. CONCLUSION: We propose the use of this online database as a hypothesis generator and method to confirm/refute findings made from patient samples and alternate model systems, to expand our understanding of HD pathogenesis. Importantly, additional tissue samples are available for further investigation of this cohort.


Assuntos
Doença de Huntington , Animais , Encéfalo , Humanos , Doença de Huntington/genética , Proteômica , Ovinos
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