RESUMO
BACKGROUND: The GPNMB single-nucleotide polymorphism rs199347 and GBA1 variants both associate with Lewy body disorder (LBD) risk. GPNMB encodes glycoprotein nonmetastatic melanoma protein B (GPNMB), a biomarker for GBA1-associated Gaucher's disease. OBJECTIVE: The aim of this study was to determine whether GPNMB levels (1) differ in LBD with and without GBA1 variants and (2) associate with rs199347 genotype. METHODS: We quantified GPNMB levels in plasma and cerebrospinal fluid (CSF) from 124 individuals with LBD with one GBA1 variant (121 plasma, 14 CSF), 631 individuals with LBD without GBA1 variants (626 plasma, 41 CSF), 9 neurologically normal individuals with one GBA1 variant (plasma), and 2 individuals with two GBA1 variants (plasma). We tested for associations between GPNMB levels and rs199347 or GBA1 status. RESULTS: GPNMB levels associate with rs199347 genotype in plasma (P = 0.022) and CSF (P = 0.007), but not with GBA1 status. CONCLUSIONS: rs199347 is a protein quantitative trait locus for GPNMB. GPNMB levels are unaltered in individuals carrying one GBA1 variant. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Assuntos
Biomarcadores , Glucosilceramidase , Doença por Corpos de Lewy , Glicoproteínas de Membrana , Polimorfismo de Nucleotídeo Único , Humanos , Feminino , Glucosilceramidase/genética , Masculino , Doença por Corpos de Lewy/genética , Doença por Corpos de Lewy/líquido cefalorraquidiano , Doença por Corpos de Lewy/sangue , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/líquido cefalorraquidiano , Idoso , Pessoa de Meia-Idade , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Idoso de 80 Anos ou mais , Genótipo , Heterozigoto , Doença de Gaucher/genética , Doença de Gaucher/sangue , Doença de Gaucher/líquido cefalorraquidianoRESUMO
Many single nucleotide polymorphisms (SNPs) identified by genome-wide association studies exert their effects on disease risk as expression quantitative trait loci (eQTL) via allele-specific expression (ASE). While databases for probing eQTLs in tissues from normal individuals exist, one may wish to ascertain eQTLs or ASE in specific tissues or disease-states not characterized in these databases. Here, we present a protocol to assess ASE of two possible target genes (GPNMB and KLHL7) of a known genome-wide association study (GWAS) Parkinson's disease (PD) risk locus in postmortem human brain tissue from PD and neurologically normal individuals. This was done using a sequence of RNA isolation, cDNA library generation, enrichment for transcripts of interest using customizable cDNA capture probes, paired-end RNA sequencing, and subsequent analysis. This method provides increased sensitivity relative to traditional bulk RNAseq-based and a blueprint that can be extended to the study of other genes, tissues, and disease states. Key features ⢠Analysis of GPNMB allele-specific expression (ASE) in brain lysates from cognitively normal controls (NC) and Parkinson's disease (PD) individuals. ⢠Builds on the ASE protocol of Mayba et al. (2014) and extends application from cells to human tissue. ⢠Increased sensitivity by enrichment for desired transcript via RNA CaptureSeq (Mercer et al., 2014). ⢠Optimized for human brain lysates from cingulate gyrus, caudate nucleus, and cerebellum.
RESUMO
Many risk loci for Parkinson's disease (PD) have been identified by genome-wide association studies (GWASs), but target genes and mechanisms remain largely unknown. We linked the GWAS-derived chromosome 7 locus (sentinel single-nucleotide polymorphism rs199347) to GPNMB through colocalization analyses of expression quantitative trait locus and PD risk signals, confirmed by allele-specific expression studies in the human brain. In cells, glycoprotein nonmetastatic melanoma protein B (GPNMB) coimmunoprecipitated and colocalized with α-synuclein (aSyn). In induced pluripotent stem cell-derived neurons, loss of GPNMB resulted in loss of ability to internalize aSyn fibrils and develop aSyn pathology. In 731 PD and 59 control biosamples, GPNMB was elevated in PD plasma, associating with disease severity. Thus, GPNMB represents a PD risk gene with potential for biomarker development and therapeutic targeting.
Assuntos
Glicoproteínas de Membrana , Doença de Parkinson , alfa-Sinucleína , Encéfalo/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Polimorfismo de Nucleotídeo Único , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismoRESUMO
BACKGROUND AND OBJECTIVES: There has been growing interest in potential roles of the immune system in the pathogenesis of Parkinson disease (PD). The aim of the current study was to comprehensively characterize phenotypic and functional profiles of circulating immune cells in patients with PD vs controls. METHODS: Peripheral blood was collected from patients with PD and age- and sex-matched neurologically normal controls (NCs) in 2 independent cohorts (discovery and validation). Comprehensive multicolor flow cytometry was performed on whole blood leukocytes and peripheral blood mononuclear cells to characterize different immune subsets and their ex vivo responses. RESULTS: The discovery cohort included 17 NCs and 12 participants with PD, and the validation cohort included 18 NCs and 18 participants with PD. Among major immune cell types, B cells appeared to be preferentially affected in PD. Proliferating B cell counts were decreased in patients with PD compared with controls. Proportions of B-cell subsets with regulatory capacity such as transitional B cells were preferentially reduced in the patients with PD, whereas proportions of proinflammatory cytokine-producing B cells increased, resulting in a proinflammatory shift of their B-cell functional cytokine responses. Unsupervised principal component analysis revealed increased expression of TNFα and GM-CSF by both B cells and T cells of patients with PD. In addition, levels of follicular T cells, an important B-cell helper T-cell population, decreased in the patients with PD, correlating with their B-cell abnormality. DISCUSSION: Our findings define a novel signature of peripheral immune cells and implicate aberrant Tfh:B-cell interactions in patients with PD.
Assuntos
Linfócitos B , Doença de Parkinson/sangue , Doença de Parkinson/imunologia , Células T Auxiliares Foliculares , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Brain injury occurs within days in simian immunodeficiency virus (SIV) or human immunodeficiency virus (HIV) infection, and some recovery may occur within weeks. Inflammation and oxidative stress associate with such injury, but what drives recovery is unknown. Chronic HIV infection associates with reduced brain frontal cortex expression of the antioxidant/anti-inflammatory enzyme heme oxygenase-1 (HO-1) and increased neuroinflammation in individuals with cognitive impairment. We hypothesized that acute regional brain injury and recovery associate with differences in regional brain HO-1 expression. Using SIV-infected rhesus macaques, we analyzed multiple brain regions through acute and chronic infection (90 days postinfection [dpi]) and quantified viral (SIV gag RNA), synaptic (PSD-95; synaptophysin), axonal (neurofilament/neurofilament light chain [NFL]), inflammatory, and antioxidant (enzymes, including heme oxygenase isoforms [HO-1, HO-2]) markers. PSD-95 was reduced in the brainstem, basal ganglia, neocortex, and cerebellum within 13 dpi, indicating acute synaptic injury throughout the brain. All areas except the brainstem recovered. Unchanged NFL was consistent with no acute axonal injury. SIV RNA expression was highest in the brainstem throughout infection, and it associated with neuroinflammation. Surprisingly, during the synaptic injury and recovery phases, HO-2, and not HO-1, progressively decreased in the brainstem. Thus, acute SIV synaptic injury occurs throughout the brain, with spontaneous recovery in regions other than the brainstem. Within the brainstem, the high SIV load and inflammation, along with reduction of HO-2, may impair recovery. In other brain regions, stable HO-2 expression, with or without increasing HO-1, may promote recovery. Our data support roles for heme oxygenase isoforms in modulating recovery from synaptic injury in SIV infection and suggest their therapeutic targeting for promoting neuronal recovery.IMPORTANCE Brain injury induced by acute simian (or human) immunodeficiency virus infection may persist or spontaneously resolve in different brain regions. Identifying the host factor(s) that promotes spontaneous recovery from such injury may reveal targets for therapeutic drug strategies for promoting recovery from acute neuronal injury. The gradual recovery from such injury observed in many, but not all, brain regions in the rhesus macaque model is consistent with the possible existence of a therapeutic window of opportunity for intervening to promote recovery, even in those regions not showing spontaneous recovery. In persons living with human immunodeficiency virus infection, such neuroprotective treatments could ultimately be considered as adjuncts to the initiation of antiretroviral drug therapy.
Assuntos
Lesões Encefálicas/metabolismo , Encéfalo/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Vírus da Imunodeficiência Símia/imunologia , Animais , Anti-Inflamatórios , Encéfalo/patologia , Encéfalo/virologia , Lesões Encefálicas/patologia , Lesões Encefálicas/virologia , Modelos Animais de Doenças , Feminino , Infecções por HIV , Heme Oxigenase-1/metabolismo , Inflamação , Macaca mulatta , Masculino , Estresse Oxidativo , Isoformas de Proteínas , Síndrome de Imunodeficiência Adquirida dos Símios/patologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/patogenicidadeRESUMO
The past 15 years have seen a boom in the use and integration of 'omic' approaches (limited here to genomic, transcriptomic, and epigenomic techniques) to study neurodegenerative disease in an unprecedented way. We first highlight advances in and the limitations of using such approaches in the neurodegenerative disease literature, with a focus on Alzheimer's disease (AD), Parkinson's disease (PD), frontotemporal lobar degeneration (FTLD), and amyotrophic lateral sclerosis (ALS). We next discuss how these studies can advance human health in the form of generating leads for downstream mechanistic investigation or yielding polygenic risk scores (PRSs) for prognostication. However, we argue that these approaches constitute a new form of molecular description, analogous to clinical or pathological description, that alone does not hold the key to solving these complex diseases.
Assuntos
Epigenoma/genética , Genoma/genética , Doenças Neurodegenerativas/genética , Transcriptoma/genética , Doença de Alzheimer/genética , Esclerose Lateral Amiotrófica/genética , Degeneração Lobar Frontotemporal/genética , Humanos , Herança Multifatorial/genética , Doenças Neurodegenerativas/patologia , Doença de Parkinson/genéticaRESUMO
BACKGROUND: Parkinson's disease (PD) is a progressive neurodegenerative disease affecting about 5 million people worldwide with no disease-modifying therapies. We sought blood-based biomarkers in order to provide molecular characterization of individuals with PD for diagnostic confirmation and prediction of progression. METHODS AND FINDINGS: In 141 plasma samples (96 PD, 45 neurologically normal control [NC] individuals; 45.4% female, mean age 70.0 years) from a longitudinally followed Discovery Cohort based at the University of Pennsylvania (UPenn), we measured levels of 1,129 proteins using an aptamer-based platform. We modeled protein plasma concentration (log10 of relative fluorescence units [RFUs]) as the effect of treatment group (PD versus NC), age at plasma collection, sex, and the levodopa equivalent daily dose (LEDD), deriving first-pass candidate protein biomarkers based on p-value for PD versus NC. These candidate proteins were then ranked by Stability Selection. We confirmed findings from our Discovery Cohort in a Replication Cohort of 317 individuals (215 PD, 102 NC; 47.9% female, mean age 66.7 years) from the multisite, longitudinally followed National Institute of Neurological Disorders and Stroke Parkinson's Disease Biomarker Program (PDBP) Cohort. Analytical approach in the Replication Cohort mirrored the approach in the Discovery Cohort: each protein plasma concentration (log10 of RFU) was modeled as the effect of group (PD versus NC), age at plasma collection, sex, clinical site, and batch. Of the top 10 proteins from the Discovery Cohort ranked by Stability Selection, four associations were replicated in the Replication Cohort. These blood-based biomarkers were bone sialoprotein (BSP, Discovery false discovery rate [FDR]-corrected p = 2.82 × 10-2, Replication FDR-corrected p = 1.03 × 10-4), osteomodulin (OMD, Discovery FDR-corrected p = 2.14 × 10-2, Replication FDR-corrected p = 9.14 × 10-5), aminoacylase-1 (ACY1, Discovery FDR-corrected p = 1.86 × 10-3, Replication FDR-corrected p = 2.18 × 10-2), and growth hormone receptor (GHR, Discovery FDR-corrected p = 3.49 × 10-4, Replication FDR-corrected p = 2.97 × 10-3). Measures of these proteins were not significantly affected by differences in sample handling, and they did not change comparing plasma samples from 10 PD participants sampled both on versus off dopaminergic medication. Plasma measures of OMD, ACY1, and GHR differed in PD versus NC but did not differ between individuals with amyotrophic lateral sclerosis (ALS, n = 59) versus NC. In the Discovery Cohort, individuals with baseline levels of GHR and ACY1 in the lowest tertile were more likely to progress to mild cognitive impairment (MCI) or dementia in Cox proportional hazards analyses adjusting for age, sex, and disease duration (hazard ratio [HR] 2.27 [95% CI 1.04-5.0, p = 0.04] for GHR, and HR 3.0 [95% CI 1.24-7.0, p = 0.014] for ACY1). GHR's association with cognitive decline was confirmed in the Replication Cohort (HR 3.6 [95% CI 1.20-11.1, p = 0.02]). The main limitations of this study were its reliance on the aptamer-based platform for protein measurement and limited follow-up time available for some cohorts. CONCLUSIONS: In this study, we found that the blood-based biomarkers BSP, OMD, ACY1, and GHR robustly associated with PD across multiple clinical sites. Our findings suggest that biomarkers based on a peripheral blood sample may be developed for both disease characterization and prediction of future disease progression in PD.
Assuntos
Biomarcadores/sangue , Doença de Parkinson/sangue , Proteômica , Idoso , Algoritmos , Amidoidrolases/sangue , Proteínas de Transporte/sangue , Progressão da Doença , Proteínas da Matriz Extracelular/sangue , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas , Osteopontina/sangue , Modelos de Riscos Proporcionais , Proteoglicanas/sangue , Reprodutibilidade dos TestesRESUMO
Since the first liver transplantation in Spain was carried out in 1984, advances in surgical technique and immunosuppressive drugs have facilitated an increase in the number of transplants performed. The present study evaluates buccodental health in liver transplant patients. A cross-sectional descriptive study was made of a sample of patients subjected to liver transplantation in Príncipes de España Hospital (Bellvitge University Health Care Complex, L'Hospitalet de Llobregat, Barcelona--Spain). Information was collected relating to demographic characteristics, general clinical history, buccodental history and intraoral exploratory findings. A total of 53 individuals were evaluated (28 males and 25 females, with a mean age of 57.6 years). The mean time elapsed from transplantation was 3 years and 9 months. The most frequent indication for liver transplantation was liver cirrhosis due to hepatitis C virus (HCV) infection (49.1% of the global series). The most widely used immunosuppressors were cyclosporine and tacrolimus. The CAOD index of the series was 11.2. In relation to periodontal disease, 22% of the dentate patients showed gingival overgrowth, while half of those with teeth had gingival recessions, and 34% presented some type of dental mobility. The examination of the oral mucosa showed fissured tongue to be the most common disorder (39.6%), followed by saburral tongue (28.3%) and xerostomia (18.9%). Buccodental pathology in these patients is related to the use of immunosuppressor medication and other factors such as a lack of preventive measures. The findings of the present study point to the need for preventive treatments in this population group.