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1.
Alzheimers Dement ; 20(3): 1815-1826, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38131463

RESUMO

INTRODUCTION: Sex influences neurodegeneration, but it has been poorly investigated in dementia with Lewy bodies (DLB). We investigated sex differences in brain atrophy in DLB using magnetic resonance imaging (MRI). METHODS: We included 436 patients from the European-DLB consortium and the Mayo Clinic. Sex differences and sex-by-age interactions were assessed through visual atrophy rating scales (n = 327; 73 ± 8 years, 62% males) and automated estimations of regional gray matter volume and cortical thickness (n = 165; 69 ± 9 years, 72% males). RESULTS: We found a higher likelihood of frontal atrophy and smaller volumes in six cortical regions in males and thinner olfactory cortices in females. There were significant sex-by-age interactions in volume (six regions) and cortical thickness (seven regions) across the entire cortex. DISCUSSION: We demonstrate that males have more widespread cortical atrophy at younger ages, but differences tend to disappear with increasing age, with males and females converging around the age of 75. HIGHLIGHTS: Male DLB patients had higher odds for frontal atrophy on radiological visual rating scales. Male DLB patients displayed a widespread pattern of cortical gray matter alterations on automated methods. Sex differences in gray matter measures in DLB tended to disappear with increasing age.


Assuntos
Doença de Alzheimer , Doença por Corpos de Lewy , Humanos , Masculino , Feminino , Doença por Corpos de Lewy/diagnóstico por imagem , Doença por Corpos de Lewy/patologia , Doença de Alzheimer/patologia , Caracteres Sexuais , Córtex Cerebral/patologia , Atrofia/patologia , Imageamento por Ressonância Magnética
2.
Mov Disord ; 38(1): 4-15, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36253921

RESUMO

Studies on dementia with Lewy bodies (DLB) have mainly focused on the degeneration of distinct cortical and subcortical regions related to the deposition of Lewy bodies. In view of the proposed trans-synaptic spread of the α-synuclein pathology, investigating the disease only in this segregated fashion would be detrimental to our understanding of its progression. In this systematic review, we summarize findings on structural and functional brain connectivity in DLB, as connectivity measures may offer better insights on how the brain is affected by the spread of the pathology. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched Web of Science, PubMed, and SCOPUS for relevant articles published up to November 1, 2021. Of 1215 identified records, we selected and systematically reviewed 53 articles that compared connectivity features between patients with DLB and healthy controls. Structural and functional magnetic resonance imaging, positron emission tomography, single-positron emission computer tomography, and electroencephalography assessments of patients revealed widespread abnormalities within and across brain networks in DLB. Frontoparietal, default mode, and visual networks and their connections to other brain regions featured the most consistent disruptions, which were also associated with core clinical features and cognitive impairments. Furthermore, graph theoretical measures revealed disease-related decreases in local and global network efficiency. This systematic review shows that structural and functional connectivity characteristics in DLB may be particularly valuable at early stages, before overt brain atrophy can be observed. This knowledge may help improve the diagnosis and prognosis in DLB as well as pinpoint targets for future disease-modifying treatments. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Alzheimer , Doença por Corpos de Lewy , Humanos , Doença por Corpos de Lewy/patologia , Corpos de Lewy/patologia , Encéfalo/patologia , Eletroencefalografia , Tomografia por Emissão de Pósitrons , Doença de Alzheimer/patologia
3.
Biochem J ; 478(17): 3221-3237, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34405855

RESUMO

The lysosomal degradation of heparan sulfate is mediated by the concerted action of nine different enzymes. Within this degradation pathway, Arylsulfatase G (ARSG) is critical for removing 3-O-sulfate from glucosamine, and mutations in ARSG are causative for Usher syndrome type IV. We developed a specific ARSG enzyme assay using sulfated monosaccharide substrates, which reflect derivatives of its natural substrates. These sulfated compounds were incubated with ARSG, and resulting products were analyzed by reversed-phase HPLC after chemical addition of the fluorescent dyes 2-aminoacridone or 2-aminobenzoic acid, respectively. We applied the assay to further characterize ARSG regarding its hydrolytic specificity against 3-O-sulfated monosaccharides containing additional sulfate-groups and N-acetylation. The application of recombinant ARSG and cells overexpressing ARSG as well as isolated lysosomes from wild-type and Arsg knockout mice validated the utility of our assay. We further exploited the assay to determine the sequential action of the different sulfatases involved in the lysosomal catabolism of 3-O-sulfated glucosamine residues of heparan sulfate. Our results confirm and extend the characterization of the substrate specificity of ARSG and help to determine the sequential order of the lysosomal catabolic breakdown of (3-O-)sulfated heparan sulfate.


Assuntos
Arilsulfatases/metabolismo , Heparitina Sulfato/análogos & derivados , Heparitina Sulfato/metabolismo , Lisossomos/metabolismo , Sulfatos/metabolismo , Acetilação , Animais , Arilsulfatases/genética , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Glucosamina/análogos & derivados , Glucosamina/metabolismo , Humanos , Camundongos , Camundongos Knockout , Especificidade por Substrato , Transfecção
4.
Bioconjug Chem ; 32(6): 1167-1174, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34060308

RESUMO

Multiple, site-specific protein conjugation is increasingly attractive for the generation of antibody-drug conjugates (ADCs). As it is important to control the number and position of cargoes in an ADC, position-selective generation of reactive sites in the protein of interest is required. Formylglycine (FGly) residues are generated by enzymatic conversion of cysteine residues embedded in a certain amino acid sequence motif with a formylglycine-generating enzyme (FGE). The addition of copper ions increases FGE activity leading to the conversion of cysteines within less readily accepted sequences. With this tuned enzyme activity, it is possible to address two different recognition sequences using two aerobic formylglycine-generating enzymes. We demonstrate an improved and facile strategy for the functionalization of a DARPin (designed ankyrin repeat protein) and the single-chain antibody scFv425-Fc, both directed against the epidermal growth factor receptor (EGFR). The single-chain antibody was conjugated with monomethyl auristatin E (MMAE) and carboxyfluorescein (CF) and successfully tested for receptor binding, internalization, and cytotoxicity in cell culture, respectively.


Assuntos
Enzimas/metabolismo , Glicina/análogos & derivados , Imunoconjugados/química , Imunoconjugados/metabolismo , Aerobiose , Repetição de Anquirina , Cobre/química , Fluoresceínas/química , Glicina/metabolismo , Oligopeptídeos/química
5.
Circ Res ; 125(9): 787-801, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31434553

RESUMO

RATIONALE: Mechanistic insight into the inflammatory response after acute myocardial infarction may inform new molecularly targeted treatment strategies to prevent chronic heart failure. OBJECTIVE: We identified the sulfatase SULF2 in an in silico secretome analysis in bone marrow cells from patients with acute myocardial infarction and detected increased sulfatase activity in myocardial autopsy samples. SULF2 (Sulf2 in mice) and its isoform SULF1 (Sulf1) act as endosulfatases removing 6-O-sulfate groups from heparan sulfate (HS) in the extracellular space, thus eliminating docking sites for HS-binding proteins. We hypothesized that the Sulfs have a role in tissue repair after myocardial infarction. METHODS AND RESULTS: Both Sulfs were dynamically upregulated after coronary artery ligation in mice, attaining peak expression and activity levels during the first week after injury. Sulf2 was expressed by monocytes and macrophages, Sulf1 by endothelial cells and fibroblasts. Infarct border zone capillarization was impaired, scar size increased, and cardiac dysfunction more pronounced in mice with a genetic deletion of either Sulf1 or Sulf2. Studies in bone marrow-chimeric Sulf-deficient mice and Sulf-deficient cardiac endothelial cells established that inflammatory cell-derived Sulf2 and endothelial cell-autonomous Sulf1 promote angiogenesis. Mechanistically, both Sulfs reduced HS sulfation in the infarcted myocardium, thereby diminishing Vegfa (vascular endothelial growth factor A) interaction with HS. Along this line, both Sulfs rendered infarcted mouse heart explants responsive to the angiogenic effects of HS-binding Vegfa164 but did not modulate the angiogenic effects of non-HS-binding Vegfa120. Treating wild-type mice systemically with the small molecule HS-antagonist surfen (bis-2-methyl-4-amino-quinolyl-6-carbamide, 1 mg/kg/day) for 7 days after myocardial infarction released Vegfa from HS, enhanced infarct border-zone capillarization, and exerted sustained beneficial effects on cardiac function and survival. CONCLUSIONS: These findings establish HS-editing Sulfs as critical inducers of postinfarction angiogenesis and identify HS sulfation as a therapeutic target for ischemic tissue repair.


Assuntos
Espaço Extracelular/metabolismo , Isquemia Miocárdica/metabolismo , Sulfatases/biossíntese , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Disponibilidade Biológica , Espaço Extracelular/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Isquemia Miocárdica/patologia , Fator A de Crescimento do Endotélio Vascular/administração & dosagem
6.
Biochem J ; 477(17): 3433-3451, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32856704

RESUMO

Mucopolysaccharidoses comprise a group of rare metabolic diseases, in which the lysosomal degradation of glycosaminoglycans (GAGs) is impaired due to genetically inherited defects of lysosomal enzymes involved in GAG catabolism. The resulting intralysosomal accumulation of GAG-derived metabolites consequently manifests in neurological symptoms and also peripheral abnormalities in various tissues like liver, kidney, spleen and bone. As each GAG consists of differently sulfated disaccharide units, it needs a specific, but also partly overlapping set of lysosomal enzymes to accomplish their complete degradation. Recently, we identified and characterized the lysosomal enzyme arylsulfatase K (Arsk) exhibiting glucuronate-2-sulfatase activity as needed for the degradation of heparan sulfate (HS), chondroitin sulfate (CS) and dermatan sulfate (DS). In the present study, we investigated the physiological relevance of Arsk by means of a constitutive Arsk knockout mouse model. A complete lack of glucuronate desulfation was demonstrated by a specific enzyme activity assay. Arsk-deficient mice show, in an organ-specific manner, a moderate accumulation of HS and CS metabolites characterized by 2-O-sulfated glucuronate moieties at their non-reducing ends. Pathophysiological studies reflect a rather mild phenotype including behavioral changes. Interestingly, no prominent lysosomal storage pathology like bone abnormalities were detected. Our results from the Arsk mouse model suggest a new although mild form of mucopolysacharidose (MPS), which we designate MPS type IIB.


Assuntos
Arilsulfatases/metabolismo , Sulfatos de Condroitina/metabolismo , Heparitina Sulfato/metabolismo , Mucopolissacaridoses/metabolismo , Animais , Arilsulfatases/genética , Sulfatos de Condroitina/genética , Ativação Enzimática , Heparitina Sulfato/genética , Camundongos , Camundongos Knockout , Mucopolissacaridoses/genética
7.
Clin Psychol Psychother ; 28(4): 852-861, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33283948

RESUMO

The increasing prevalence of stress-related disorders such as burnout urges the need for specialized treatment approaches. Programmes combining psychotherapy and regenerative interventions emerge to be the most successful. However, evaluated therapy programmes are scarce and usually involve subjective symptom quantification without consideration of physiologic parameters. The aim of the present exploratory, single-group study was the multimodal investigation of the effectiveness of a specialized holistic therapy programme by assessing symptoms and biological markers of chronic stress. Seventy-one in-patients (39 men/32 women; age 46.8 ± 9.9 years) of a specialized burnout ward with the additional diagnosis of burnout (Z73.0) in conjunction with a main diagnosis of depressive disorder (F32 or F33) according to the International Classification of Diseases (ICD)-10 were included in the study. In addition to symptomatology, the stress-responsive biomarkers heart rate variability (HRV) and serum brain-derived neurotrophic factor (BDNF) were measured in patients at admittance to and discharge from the burnout ward applying a 6-week specialized treatment programme. At discharge, patients showed a significant reduction of symptom burden and a significant increase in serum BDNF, while HRV remained unchanged. The findings implicate that the therapy programme may have beneficial effects on symptomatology and neuroplasticity of patients with burnout. As therapy was often supplemented by psychopharmacological treatment, a relevant influence of antidepressant medication especially on BDNF has to be considered.


Assuntos
Esgotamento Psicológico/psicologia , Esgotamento Psicológico/terapia , Psicoterapia , Biomarcadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Chembiochem ; 21(24): 3580-3593, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-32767537

RESUMO

Formylglycine-generating enzymes specifically oxidize cysteine within the consensus sequence CxPxR to Cα -formylglycine (FGly). This noncanonical electrophilic amino acid can subsequently be addressed selectively by bioorthogonal hydrazino-iso-Pictet-Spengler (HIPS) or Knoevenagel ligation to attach payloads like fluorophores or drugs to proteins to obtain a defined payload-to-protein ratio. However, the disadvantages of these conjugation techniques include the need for a large excess of conjugation building block, comparably low reaction rates and limited stability of FGly-containing proteins. Therefore, functionalized clickable HIPS and tandem Knoevenagel building blocks were synthesized, conjugated to small proteins (DARPins) and subsequently linked to strained alkyne-containing payloads for protein labeling. This procedure allowed the selective bioconjugation of one or two DBCO-carrying payloads with nearly stoichiometric amounts at low concentrations. Furthermore, an azide-modified tandem Knoevenagel building block enabled the synthesis of branched PEG linkers and the conjugation of two fluorophores, resulting in an improved signal-to-noise ratio in live-cell fluorescence-imaging experiments targeting the EGF receptor.


Assuntos
Azidas/química , Reagentes de Ligações Cruzadas/química , Receptores ErbB/análise , Corantes Fluorescentes/química , Glicina/análogos & derivados , Reagentes de Ligações Cruzadas/síntese química , Corantes Fluorescentes/síntese química , Glicina/química , Humanos , Estrutura Molecular , Imagem Óptica , Células Tumorais Cultivadas
9.
J Inherit Metab Dis ; 43(6): 1298-1309, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32749716

RESUMO

Multiple sulfatase deficiency (MSD) is an ultra-rare neurodegenerative disorder caused by pathogenic variants in SUMF1. This gene encodes formylglycine-generating enzyme (FGE), a protein required for sulfatase activation. The clinical course of MSD results from additive effect of each sulfatase deficiency, including metachromatic leukodystrophy (MLD), several mucopolysaccharidoses (MPS II, IIIA, IIID, IIIE, IVA, VI), chondrodysplasia punctata, and X-linked ichthyosis. While it is known that affected individuals demonstrate a complex and severe phenotype, the genotype-phenotype relationship and detailed clinical course is unknown. We report on 35 cases enrolled in our retrospective natural history study, n = 32 with detailed histories. Neurologic function was longitudinally assessed with retrospective scales. Biochemical and computational modeling of novel SUMF1 variants was performed. Genotypes were classified based on predicted functional change, and each individual was assigned a genotype severity score. The median age at symptom onset was 0.25 years; median age at diagnosis was 2.7 years; and median age at death was 13 years. All individuals demonstrated developmental delay, and only a subset of individuals attained ambulation and verbal communication. All subjects experienced an accumulating systemic symptom burden. Earlier age at symptom onset and severe variant pathogenicity correlated with poor neurologic outcomes. Using retrospective deep phenotyping and detailed variant analysis, we defined the natural history of MSD. We found that attenuated cases can be distinguished from severe cases by age of onset, attainment of ambulation, and genotype. Results from this study can help inform prognosis and facilitate future study design.


Assuntos
Leucodistrofia Metacromática/genética , Mucopolissacaridoses/genética , Doença da Deficiência de Múltiplas Sulfatases/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Adolescente , Criança , Pré-Escolar , Feminino , Genótipo , Glicina/análogos & derivados , Glicina/genética , Glicina/metabolismo , Humanos , Lactente , Internacionalidade , Leucodistrofia Metacromática/patologia , Masculino , Mucopolissacaridoses/patologia , Doença da Deficiência de Múltiplas Sulfatases/patologia , Mutação , Fenótipo , Doenças Raras , Estudos Retrospectivos , Sulfatases/deficiência , Sulfatases/genética
10.
Chembiochem ; 20(16): 2074-2078, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31215729

RESUMO

Formylglycine-generating enzymes provide a convenient tool for site-specific protein derivatization. Their ability to oxidize cysteine or serine residues within a defined consensus sequence to Cα -formylglycine (FGly) allows for the targeted introduction of a unique chemical handle for various bioconjugation reactions. In recent years, oxygen-dependent FGly-generating enzyme saw broad use in protein functionalization and the generation of protein conjugates. Yet, the FGly-generating system AtsB, along with its capability to convert unusual aldehyde tag sequences, remains mostly unused. Herein, the ability of AtsB from Methanosarcina mazei to convert nonclassical aldehyde tags of the SX(A/P)XR-type and its potential use in bioconjugation chemistry are demonstrated.


Assuntos
Proteínas Ferro-Enxofre/química , Methanosarcina/química , S-Adenosilmetionina/química , Aldeídos/química , Radicais Livres/química , Estrutura Molecular , Serina/química
11.
Biol Chem ; 400(3): 289-297, 2019 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-30291781

RESUMO

Site-specific bioconjugation strategies offer many possibilities for directed protein modifications. Among the various enzyme-based conjugation protocols, formylglycine-generating enzymes allow to posttranslationally introduce the amino acid Cα-formylglycine (FGly) into recombinant proteins, starting from cysteine or serine residues within distinct consensus motifs. The aldehyde-bearing FGly-residue displays orthogonal reactivity to all other natural amino acids and can, therefore, be used for site-specific labeling reactions on protein scaffolds. In this review, the state of research on catalytic mechanisms and consensus motifs of different formylglycine-generating enzymes, as well as labeling strategies and applications of FGly-based bioconjugations are presented.


Assuntos
Glicina/análogos & derivados , Sulfatases/metabolismo , Glicina/biossíntese , Glicina/química , Glicina/metabolismo , Humanos , Modelos Moleculares , Estrutura Molecular , Sulfatases/química
12.
Appl Microbiol Biotechnol ; 103(5): 2229-2241, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30631897

RESUMO

L-Amino acid oxidases (LAAOs) are flavoproteins, which use oxygen to deaminate L-amino acids and produce the corresponding α-keto acids, ammonia, and hydrogen peroxide. Here we describe the heterologous expression of LAAO4 from the fungus Hebeloma cylindrosporum without signal sequence as fusion protein with a 6His tag in Escherichia coli and its purification. 6His-hcLAAO4 could be activated by exposure to acidic pH, the detergent sodium dodecyl sulfate, or freezing. The enzyme converted 14 proteinogenic L-amino acids with L-glutamine, L-leucine, L-methionine, L-phenylalanine, L-tyrosine, and L-lysine being the best substrates. Methyl esters of these L-amino acids were also accepted. Even ethyl esters were converted but with lower activity. Km values were below 1 mM and vmax values between 19 and 39 U mg-1 for the best substrates with the acid-activated enzyme. The information for an N-terminal aldehyde tag was added to the coding sequence. Co-expressed formylglycine-generating enzyme was used to convert a cysteine residue in the aldehyde tag to a Cα-formylglycine residue. The aldehyde tag did not change the properties of the enzyme. Purified Ald-6His-hcLAAO4 was covalently bound to a hexylamine resin via the Cα-formylglycine residue. The immobilized enzyme could be reused repeatedly to generate phenylpyruvate from L-phenylalanine with a total turnover number of 17,600 and was stable for over 40 days at 25 °C.


Assuntos
Enzimas Imobilizadas/metabolismo , Hebeloma/enzimologia , L-Aminoácido Oxidase/metabolismo , Fenilalanina/metabolismo , Ácidos Fenilpirúvicos/metabolismo , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , L-Aminoácido Oxidase/genética , Proteínas Recombinantes de Fusão/genética
13.
Genet Med ; 20(9): 1004-1012, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29300381

RESUMO

PURPOSE: We aimed to identify the cause of disease in patients suffering from a distinctive, atypical form of Usher syndrome. METHODS: Whole-exome and genome sequencing were performed in five patients from three families of Yemenite Jewish origin, suffering from distinctive retinal degeneration phenotype and sensorineural hearing loss. Functional analysis of the wild-type and mutant proteins was performed in human fibrosarcoma cells. RESULTS: We identified a homozygous founder missense variant, c.133G>T (p.D45Y) in arylsulfatase G (ARSG). All patients shared a distinctive retinal phenotype with ring-shaped atrophy along the arcades engirdling the fovea, resulting in ring scotoma. In addition, patients developed moderate to severe sensorineural hearing loss. Both vision and hearing loss appeared around the age of 40 years. The identified variant affected a fully conserved amino acid that is part of the catalytic site of the enzyme. Functional analysis of the wild-type and mutant proteins showed no basal activity of p.D45Y. CONCLUSION: Homozygosity for ARSG-p.D45Y in humans leads to protein dysfunction, causing an atypical combination of late-onset Usher syndrome. Although there is no evidence for generalized clinical manifestations of lysosomal storage diseases in this set of patients, we cannot rule out the possibility that mild and late-onset symptoms may appear.


Assuntos
Arilsulfatases/genética , Síndromes de Usher/genética , Adulto , Arilsulfatases/metabolismo , Sequência de Bases , Análise Mutacional de DNA , Feminino , Efeito Fundador , Homozigoto , Humanos , Masculino , Mutação , Mutação de Sentido Incorreto , Linhagem , Retina/metabolismo , Degeneração Retiniana/enzimologia , Degeneração Retiniana/genética , Retinose Pigmentar/enzimologia , Retinose Pigmentar/genética , Sequenciamento do Exoma , Sequenciamento Completo do Genoma
14.
Mol Genet Metab ; 123(3): 337-346, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29397290

RESUMO

Multiple sulfatase deficiency (MSD) is an ultra-rare neurodegenerative disorder that results in defective sulfatase post-translational modification. Sulfatases in the body are activated by a unique protein, formylglycine-generating enzyme (FGE) that is encoded by SUMF1. When FGE is absent or insufficient, all 17 known human sulfatases are affected, including the enzymes associated with metachromatic leukodystrophy (MLD), several mucopolysaccharidoses (MPS II, IIIA, IIID, IVA, VI), chondrodysplasia punctata, and X-linked ichthyosis. As such, individuals demonstrate a complex and severe clinical phenotype that has not been fully characterized to date. In this report, we describe two individuals with distinct clinical presentations of MSD. Also, we detail a comprehensive systems-based approach to the management of individuals with MSD, from the initial diagnostic evaluation to unique multisystem issues and potential management options. As there have been no natural history studies to date, the recommendations within this report are based on published studies and consensus opinion and underscore the need for future research on evidence-based outcomes to improve management of children with MSD.


Assuntos
Consenso , Doença da Deficiência de Múltiplas Sulfatases/terapia , Doenças Raras/terapia , Sulfatases/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Pré-Escolar , Feminino , Humanos , Masculino , Doença da Deficiência de Múltiplas Sulfatases/diagnóstico , Doença da Deficiência de Múltiplas Sulfatases/etiologia , Doença da Deficiência de Múltiplas Sulfatases/patologia , Mutação , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Processamento de Proteína Pós-Traducional/genética , Doenças Raras/diagnóstico , Doenças Raras/etiologia , Sulfatases/deficiência
15.
J Exp Bot ; 69(22): 5341-5354, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30169821

RESUMO

Forty years ago, 12-oxophytodienoic acid (12-OPDA) was reported as a prostaglandin (PG)-like metabolite of linolenic acid found in extracts of flaxseed. Since then, numerous studies have determined the role of 12-OPDA in regulating plant immunity, seed dormancy, and germination. This review summarizes our current knowledge of the regulation of 12-OPDA synthesis in the chloroplast and 12-OPDA-dependent signaling in gene expression and targeting protein functions. We describe the properties of OPDA that are linked to the activities of PGs, which are derived from arachidonic acid and act as tissue hormones in animals, including humans. The similarity of OPDA with bioactive PGs is particularly evident for the most-studied cyclopentenone, PG 15-dPGJ2. In addition to chemical approaches towards 12-OPDA synthesis, bio-organic synthesis strategies for 12-OPDA and analogous substances have recently been established. The resulting availability of OPDA will aid the identification of additional effector proteins, help in elucidating the mechanisms of OPDA sensing and transmission, and will foster the analysis of the physiological responses to OPDA in plants. There is a need to determine the compartmentation and transport of 12-OPDA and its conjugates, over long distances as well as short. It will be important to further study OPDA in animal and human cells, for example with respect to beneficial anti-inflammatory and anti-cancer activities.


Assuntos
Aclimatação , Cloroplastos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Células Vegetais/metabolismo , Transdução de Sinais , Oxilipinas , Estresse Fisiológico
16.
Angew Chem Int Ed Engl ; 57(24): 7245-7249, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29579347

RESUMO

Formylglycine-generating enzymes are of increasing interest in the field of bioconjugation chemistry. They catalyze the site-specific oxidation of a cysteine residue to the aldehyde-containing amino acid Cα -formylglycine (FGly). This non-canonical residue can be generated within any desired target protein and can subsequently be used for bioorthogonal conjugation reactions. The prototypic formylglycine-generating enzyme (FGE) and the iron-sulfur protein AtsB display slight variations in their recognition sequences. We designed specific tags in peptides and proteins that were selectively converted by the different enzymes. Combination of the different tag motifs within a single peptide or recombinant protein enabled the independent and consecutive introduction of two formylglycine residues and the generation of heterobifunctionalized protein conjugates.


Assuntos
Bactérias/enzimologia , Glicina/análogos & derivados , Linhagem Celular , Cisteína/metabolismo , Glicina/metabolismo , Humanos , Proteínas Ferro-Enxofre/metabolismo , Methanosarcina/enzimologia , Oxirredução , Sulfatases/metabolismo
17.
Hum Mol Genet ; 24(7): 1856-68, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25452429

RESUMO

Deficiency of arylsulfatase G (ARSG) leads to a lysosomal storage disease in mice resembling biochemical and pathological features of the mucopolysaccharidoses and particularly features of mucopolysaccharidosis type III (Sanfilippo syndrome). Here we show that Arsg KO mice share common neuropathological findings with other Sanfilippo syndrome models and patients, but they can be clearly distinguished by the limitation of most phenotypic alterations to the cerebellum, presenting with ataxia as the major neurological finding. We determined in detail the expression of ARSG in the central nervous system and observed highest expression in perivascular macrophages (which are characterized by abundant vacuolization in Arsg KO mice) and oligodendrocytes. To gain insight into possible mechanisms leading to ataxia, the pathology in older adult mice (>12 months) was investigated in detail. This study revealed massive loss of Purkinje cells and gliosis in the cerebellum, and secondary accumulation of glycolipids like GM2 and GM3 gangliosides and unesterified cholesterol in surviving Purkinje cells, as well as neurons of some other brain regions. The abundant presence of ubiquitin and p62-positive aggregates in degenerating Purkinje cells coupled with the absence of significant defects in macroautophagy is consistent with lysosomal membrane permeabilization playing a role in the pathogenesis of Arsg-deficient mice and presumably Sanfilippo disease in general. Our data delineating the phenotype of mucopolysaccharidosis IIIE in a mouse KO model should help in the identification of possible human cases of this disease.


Assuntos
Arilsulfatases/deficiência , Ataxia/enzimologia , Mucopolissacaridose III/enzimologia , Animais , Arilsulfatases/genética , Ataxia/genética , Ataxia/metabolismo , Ataxia/patologia , Cerebelo/citologia , Cerebelo/metabolismo , Modelos Animais de Doenças , Feminino , Gliose/metabolismo , Glicolipídeos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Knockout , Mucopolissacaridose III/genética , Mucopolissacaridose III/metabolismo , Mucopolissacaridose III/patologia , Células de Purkinje/metabolismo
18.
Mol Genet Metab ; 121(3): 252-258, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28566233

RESUMO

Multiple sulfatase deficiency (MSD) is a rare inherited metabolic disease caused by defective cellular sulfatases. Activity of sulfatases depends on post-translational modification catalyzed by formylglycine-generating enzyme (FGE), encoded by the SUMF1 gene. SUMF1 pathologic variants cause MSD, a syndrome presenting with a complex phenotype. We describe the first Polish patient with MSD caused by a yet undescribed pathologic variant c.337G>A [p.Glu113Lys] (i.e. p.E113K) in heterozygous combination with the known deletion allele c.519+5_519+8del [p.Ala149_Ala173del]. The clinical picture of the patient initially suggested late infantile metachromatic leukodystrophy, with developmental delay followed by regression of visual, hearing and motor abilities as the most apparent clinical symptoms. Transient signs of ichthyosis and minor dysmorphic features guided the laboratory workup towards MSD. Since MSD is a rare disease and there is a variable clinical spectrum, we thoroughly describe the clinical outcome of our patient. The FGE-E113K variant, expressed in cell culture, correctly localized to the endoplasmic reticulum but was retained intracellularly in contrast to the wild type FGE. Analysis of FGE-mediated activation of steroid sulfatase in immortalized MSD cells revealed that FGE-E113K exhibited only approx. 15% of the activity of wild type FGE. Based on the crystal structure we predict that the exchange of glutamate-113 against lysine should induce a strong destabilization of the secondary structure, possibly affecting the folding for correct disulfide bridging between C235-C346 as well as distortion of the active site groove that could affect both the intracellular stability as well as the activity of FGE. Thus, the novel variant of the SUMF1 gene obviously results in functionally impaired FGE protein leading to a severe late infantile type of MSD.


Assuntos
Doença da Deficiência de Múltiplas Sulfatases/genética , Doença da Deficiência de Múltiplas Sulfatases/fisiopatologia , Sulfatases/genética , Células Cultivadas , Pré-Escolar , Simulação por Computador , Enzimas/química , Enzimas/genética , Glicina/análogos & derivados , Humanos , Ictiose , Masculino , Doença da Deficiência de Múltiplas Sulfatases/etnologia , Mutação de Sentido Incorreto , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Fenótipo , Polônia , Processamento de Proteína Pós-Traducional , Sulfatases/química , Sulfatases/metabolismo
19.
Neuropsychobiology ; 75(3): 100-116, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29258073

RESUMO

Schizophrenia research has been in a deadlock for many decades. Despite important advances in clinical treatment, there are still major concerns regarding long-term psychosocial reintegration and disease management, biological heterogeneity, unsatisfactory predictors of individual course and treatment strategies, and a confusing variety of controversial theories about its etiology and pathophysiological mechanisms. In the present perspective on schizophrenia research, we first discuss a methodological pitfall in contemporary schizophrenia research inherent in the attempt to link mental phenomena with the brain: we claim that the time-honored phenomenological method of defining mental symptoms should not be contaminated with the naturalistic approach of modern neuroscience. We then describe our Systems Neuroscience of Psychosis (SyNoPsis) project, which aims to overcome this intrinsic problem of psychiatric research. Considering schizophrenia primarily as a disorder of interindividual communication, we developed a neurobiologically informed semiotics of psychotic disorders, as well as an operational clinical rating scale. The novel psychopathology allows disentangling the clinical manifestations of schizophrenia into behavioral domains matching the functions of three well-described higher-order corticobasal brain systems involved in interindividual human communication, namely, the limbic, associative, and motor loops, including their corticocortical sensorimotor connections. The results of several empirical studies support the hypothesis that the proposed three-dimensional symptom structure, segregated into the affective, the language, and the motor domain, can be specifically mapped onto structural and functional abnormalities of the respective brain systems. New pathophysiological hypotheses derived from this brain system-oriented approach have helped to develop and improve novel treatment strategies with noninvasive brain stimulation and practicable clinical parameters. In clinical practice, the novel psychopathology allows confining the communication deficits of the individual patient, shifting attention from the symptoms to the intact resources. We have studied this approach and observed important advantages for therapeutic alliances, personalized treatment, and de-escalation strategies. Future studies will further conjoin clinical definitions of psychotic symptoms with brain structures and functions, and disentangle structural and functional deficit patterns within these systems to identify neurobiologically distinct subsyndromes. Neurobiologically homogeneous patient groups may provide new momentum for treatment research. Finally, lessons learned from schizophrenia research may contribute to developing a comprehensive perspective on human experience and behavior that integrates methodologically distinct, but internally consistent, insights from humanities and neuroscience.


Assuntos
Encéfalo/fisiopatologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Animais , Humanos , Modelos Neurológicos , Vias Neurais , Neurociências , Projetos de Pesquisa
20.
Hum Brain Mapp ; 37(3): 924-32, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26663662

RESUMO

Low self-referential thoughts are associated with better concentration, which leads to deeper encoding and increases learning and subsequent retrieval. There is evidence that being engaged in externally rather than internally focused tasks is related to low neural activity in the default mode network (DMN) promoting open mind and the deep elaboration of new information. Thus, reduced DMN activity should lead to enhanced concentration, comprehensive stimulus evaluation including emotional categorization, deeper stimulus processing, and better long-term retention over one whole week. In this fMRI study, we investigated brain activation preceding and during incidental encoding of emotional pictures and on subsequent recognition performance. During fMRI, 24 subjects were exposed to 80 pictures of different emotional valence and subsequently asked to complete an online recognition task one week later. Results indicate that neural activity within the medial temporal lobes during encoding predicts subsequent memory performance. Moreover, a low activity of the default mode network preceding incidental encoding leads to slightly better recognition performance independent of the emotional perception of a picture. The findings indicate that the suppression of internally-oriented thoughts leads to a more comprehensive and thorough evaluation of a stimulus and its emotional valence. Reduced activation of the DMN prior to stimulus onset is associated with deeper encoding and enhanced consolidation and retrieval performance even one week later. Even small prestimulus lapses of attention influence consolidation and subsequent recognition performance.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estimulação Luminosa , Tempo , Adulto Jovem
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