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Despite the efforts to identify fluid biomarkers to improve diagnosis of Frontotemporal dementia (FTD), only a few candidates have been described in recent years. In a previous study, we identified three circulating miRNAs (miR-92a-3p, miR-320a and miR-320b) differentially expressed in FTD patients with respect to healthy controls and/or Alzheimer's disease (AD) patients. Now, we investigated whether those changes could be due to miRNAs contained in neuron-derived extracellular vesicles (NDEVs). We also evaluated miRNAs content in total plasma EVs and in CSF samples. The analysis of plasma NDEVs carried out on 40 subjects including controls (n = 13), FTD (n = 13) and AD (n = 14) patients, showed that both miR-92a-3p and miR-320a levels were triplicated in the FTD group if compared with CT and AD patients. Increased levels of the same miRNAs were found also in CSF derived from FTD group compared to CTs. No differences were observed in expression levels of miR-320b among the three groups. Worthy of note, all miRNAs analysed were increased in an FTD cell model, MAPT IVS10 + 16 neurons. Our results suggest that miR-92a and miR-320a in NDEVs could be proposed as FTD biomarkers.
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BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a highly debilitating neurodegenerative condition. Despite recent advancements in understanding the molecular mechanisms underlying ALS, there have been no significant improvements in therapeutic options for ALS patients in recent years. Currently, there is no cure for ALS, and the only approved treatment in Europe is riluzole, which has been shown to slow the disease progression and prolong survival by approximately 3 months. Recently, tauroursodeoxycholic acid (TUDCA) has emerged as a promising and effective treatment for neurodegenerative diseases due to its neuroprotective activities. METHODS: The ongoing TUDCA-ALS study is a double-blinded, parallel arms, placebo-controlled, randomized multicenter phase III trial with the aim to assess the efficacy and safety of TUDCA as add-on therapy to riluzole in patients with ALS. The primary outcome measure is the treatment response defined as a minimum of 20% improvement in the ALS Functional Rating Scale-Revised (ALSFRS-R) slope during the randomized treatment period (18 months) compared to the lead-in period (3 months). Randomization will be stratified by country. Primary analysis will be conducted based on the intention-to-treat principle through an unadjusted logistic regression model. Patient recruitment commenced on February 22, 2019, and was closed on December 23, 2021. The database will be locked in September 2023. DISCUSSION: This paper provides a comprehensive description of the statistical analysis plan in order to ensure the reproducibility of the analysis and avoid selective reporting of outcomes and data-driven analysis. Sensitivity analyses have been included in the protocol to assess the impact of intercurrent events related to the coronavirus disease 2019. By focusing on clinically meaningful and robust outcomes, this trial aims to determine whether TUDCA can be effective in slowing the disease progression in patients with ALS. TRIAL REGISTRATION: ClinicalTrials.gov NCT03800524 . Registered on January 11, 2019.
Assuntos
Esclerose Lateral Amiotrófica , Fármacos Neuroprotetores , Humanos , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/tratamento farmacológico , Riluzol , Fármacos Neuroprotetores/efeitos adversos , Reprodutibilidade dos Testes , Método Duplo-Cego , Resultado do Tratamento , Progressão da DoençaRESUMO
Phase II studies on tauro-urso-deoxycholic acid (TUDCA) raised the promise of safety and efficacy in patients with amyotrophic lateral sclerosis, a currently incurable and devastating disease. We review the available evidence on the efficacy and safety of TUDCA, administered alone or in combination, by analyzing and comparing published and ongoing studies on amyotrophic lateral sclerosis. Two independent phase II studies (using TUDCA solo or combined with sodium phenylbutyrate) showed similar efficacy in slowing disease progression measured by functional scales. One open-label follow-up TUDCA+sodium phenylbutyrate study suggested a benefit on survival. Two subsequent phase III studies with TUDCA (solo or combined with sodium phenylbutyrate) have been initiated and are currently ongoing. Their completion is expected by the end of 2023 and beginning of 2024. Evidence collected by phase II studies indicates that there are no safety concerns in patients with amyotrophic lateral sclerosis. The efficacy shown in phase II studies was considered sufficient to grant approval in some countries but not in others, owing to discrepant views on the strength of evidence. It will be necessary to wait for the results of ongoing phase III studies to attain a full appreciation of these data.
Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Fenilbutiratos , Ácido Tauroquenodesoxicólico/efeitos adversosRESUMO
Recent phase II pilot clinical trials suggested that tauro-urso-deoxycholic acid (TUDCA) might slow functional decline and increase survival in patients with amyotrophic lateral sclerosis (ALS). We performed a multivariate analysis of the original TUDCA cohort to better define the treatment effect and allow comparability with other trials. Linear regression slope analysis showed statistical differences in the decline rate, favoring the active treatment arm (p-value < 0.01; -0.262 for the TUDCA group and -0.388 for the placebo group). Mean survival time, estimated by the Kaplan-Meier analysis, showed a 1-month difference, favoring active treatment (log-rank test p-value = 0.092). Cox regression analysis demonstrated that placebo treatment was associated with a higher risk of death (p-value = 0.055). These data further support the disease-modifying effect of TUDCA monotherapy and raise the question of what could be the additional effect of combining TUDCA with sodium phenylbutyrate.
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Despite numerous efforts and studies over the last three decades, Alzheimer's disease (AD) remains a disorder not fully understood and incurable so far. Development of induced pluripotent stem cell (iPSC) technology to obtain terminally differentiated neurons from adult somatic cells revolutionized the study of AD, providing a powerful tool for modelling the disease and for screening candidate drugs. Indeed, iPSC reprogramming allowed generation of neurons from both sporadic and familial AD patients with the promise to recapitulate the early pathological mechanisms in vitro and to identify novel targets. Interestingly, NPS 2143, a negative allosteric modulator of the calcium sensing receptor, has been indicated as a possible therapeutic for AD. In the present study, we assessed the potential of our iPSC-based familial AD cellular model as a platform for drug testing. We found that iPSC-derived neurons respond to treatment with γ-secretase inhibitor, modifying the physiological amyloid-ß protein precursor (AßPP) processing and amyloid-ß (Aß) secretion. Moreover, we demonstrated the expression of calcium sensing receptor (CaSR) protein in human neurons derived from healthy and familial AD subjects. Finally, we showed that calcilytic NPS 2143 induced a changing of Aß and sAßPPα secreted into conditioned media and modulation of CaSR and PSEN1 expression at the plasma membrane of AD neurons. Overall, our findings suggest that NPS 2143 affects important AD processes in a relevant in vitro system of familial AD.
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Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Naftalenos/farmacologia , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Presenilina-1/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Mutação/efeitos dos fármacos , Mutação/fisiologia , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/antagonistas & inibidores , Presenilina-1/genéticaRESUMO
Mucopolysaccharidosis II (MPS II) is a lysosomal storage disorder (LSD), caused by iduronate 2-sulphatase (IDS) enzyme dysfunction. The neuropathology of the disease is not well understood, although the neural symptoms are currently incurable. MPS II-patient derived iPSC lines were established and differentiated to neuronal lineage. The disease phenotype was confirmed by IDS enzyme and glycosaminoglycan assay. MPS II neuronal precursor cells (NPCs) showed significantly decreased self-renewal capacity, while their cortical neuronal differentiation potential was not affected. Major structural alterations in the ER and Golgi complex, accumulation of storage vacuoles, and increased apoptosis were observed both at protein expression and ultrastructural level in the MPS II neuronal cells, which was more pronounced in GFAP + astrocytes, with increased LAMP2 expression but unchanged in their RAB7 compartment. Based on these finding we hypothesize that lysosomal membrane protein (LMP) carrier vesicles have an initiating role in the formation of storage vacuoles leading to impaired lysosomal function. In conclusion, a novel human MPS II disease model was established for the first time which recapitulates the in vitro neuropathology of the disorder, providing novel information on the disease mechanism which allows better understanding of further lysosomal storage disorders and facilitates drug testing and gene therapy approaches.
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Células-Tronco Pluripotentes Induzidas/metabolismo , Lisossomos/metabolismo , Modelos Biológicos , Mucopolissacaridose II/metabolismo , Diferenciação Celular , Células Cultivadas , Citometria de Fluxo , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Mucopolissacaridose II/patologiaRESUMO
We have recently isolated a new isoform of recombinant manganese superoxide dismutase (rMnSOD) which provides a potent antitumor activity and strongly counteracts the occurrence of oxidative stress and tissue inflammation. This isoform, in addition to the enzymatic action common to all SODs, also shows special functional and structural properties, essentially due to the presence of a first leader peptide that allows the protein to enter easily into cells. Among endogenous antioxidants, SOD constitutes the first line of natural defence against pathological effects induced by an excess of free radicals. Here, we firstly describe the effects of our rMnSOD administration on the proliferant and malignant undifferentiated human neuroblastoma SK-N-BE cell line. Moreover, we also test the effects of rMnSOD in the all trans retinoic-differentiated SK-N-BE neuron-like cells, a quiescent "not malignant" model. While rMnSOD showed an antitumor activity on proliferating cells, a poor sensitivity to rMnSOD overload in retinoid-differentiated neuron-like cells was observed. However, in the latter case, in presence of experimental-induced oxidative stress, overcharge of rMnSOD enhanced the oxidant effects, through an increase of H2O2 due to low activity of both catalase and glutathione peroxidase. In conclusion, our data show that rMnSOD treatment exerts differential effects, which depend upon both cell differentiation and redox balance, addressing attention to the potential use of the recombinant enzyme on differentiated neurons. These facts ultimately pave the way for further preclinical studies aimed at evaluation of rMnSOD effects in models of neurodegenerative diseases.
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Diferenciação Celular/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Antioxidantes/farmacologia , Catalase/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/metabolismo , Superóxido Dismutase/efeitos dos fármacosRESUMO
Biomolecules adsorbed on nanoparticles are known to confer a biological identity to nanoparticles, mediating the interactions with cells and biological barriers. However, how these molecules are presented on the particle surface in biological milieu remains unclear. The central aim of this study is to identify key protein recognition motifs and link them to specific cell-receptor interactions. Here, we employed an immuno-mapping technique to quantify epitope presentations of two major proteins in the serum corona, low-density lipoprotein and immunoglobulin G. Combining with a purpose-built receptor expression system, we show that both proteins present functional motifs to allow simultaneous recognition by low-density lipoprotein receptor and Fc-gamma receptor I of the corona. Our results suggest that the "labeling" of nanoparticles by biomolecular adsorption processes allows for multiple pathways in biological processes in which they may be "mistaken" for endogenous objects, such as lipoproteins, and exogenous ones, such as viral infections.
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Nanopartículas/química , Coroa de Proteína/química , Receptores de IgG/química , Receptores de LDL/química , Adsorção , Sítios de Ligação , Células Cultivadas , Mapeamento de Epitopos , Células HEK293 , Humanos , Imunoglobulina G/química , Lipoproteínas LDL/química , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
Characterizing the orientation of covalently conjugated proteins on nanoparticles, produced for in vitro and in vivo targeting, though an important feature of such a system, has proved challenging. Although extensive physicochemical characterization of targeting nanoparticles can be addressed in detail, relevant biological characterization of the nanointerface is crucial in order to select suitable nanomaterials for further in vitro or in vivo experiments. In this work, we adopt a methodology using antibody fragments (Fab) conjugated to gold nanoparticles (immunogold) to map the available epitopes on a transferrin grafted silica particle (SiO2-PEG8-Tf) as a proxy methodology to predict nanoparticle biological function, and therefore cellular receptor engagement. Data from the adopted method suggest that, on average, only â¼3.5% of proteins grafted on the SiO2-PEG8-Tf nanoparticle surface have a favorable orientation for recognition by the cellular receptor.
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Anticorpos/química , Ouro/química , Nanopartículas Metálicas/química , Dióxido de Silício/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
Nanoparticles interacting with, or derived from, living organisms are almost invariably coated in a variety of biomolecules presented in complex biological milieu, which produce a bio-interface or 'biomolecular corona' conferring a biological identity to the particle. Biomolecules at the surface of the nanoparticle-biomolecule complex present molecular fragments that may be recognized by receptors of cells or biological barriers, potentially engaging with different biological pathways. Here we demonstrate that using intense fluorescent reporter binders, in this case antibodies bound to quantum dots, we can map out the availability of such recognition fragments, allowing for a rapid and meaningful biological characterization. The application in microfluidic flow, in small detection volumes, with appropriate thresholding of the detection allows the study of even complex nanoparticles in realistic biological milieu, with the emerging prospect of making direct connection to conditions of cell level and in vivo experiments.
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Citometria de Fluxo/métodos , Nanopartículas/química , Proteínas/química , Pontos Quânticos , Algoritmos , Anticorpos/química , Anticorpos/metabolismo , Humanos , Nanopartículas/metabolismo , Ligação Proteica , Proteínas/imunologia , Proteínas/metabolismo , Albumina Sérica/química , Albumina Sérica/imunologia , Albumina Sérica/metabolismo , Espectrometria de Fluorescência , Transferrina/química , Transferrina/imunologia , Transferrina/metabolismoRESUMO
Nanoparticles (NPs) functionalized with two active targeting ligands have been proposed in drug delivery for their promising capability to stimulate different pathways with one object. Due to the multivalency, the construction and analysis of the effective surface of such bifunctional nanoparticles, however, is significantly more complex than for nanoparticles bearing only one ligand. Here, we optimize construction and analysis of bifunctional NPs containing recognizable combinations of human serum albumin (HSA), transferrin (Tf), and epidermal growth factor (EGF) on fluorescent silica NPs grafted via common polyethylene glycol (PEG) linkers as a model system. Combined with an overall protein quantification, a mapping of exposed recognizable sequences using monoclonal antibodies conjugated to gold nanoparticles (AuNPs) or quantum dots (QDs) for enhanced spectroscopic and microscopic detection revealed that active protein sequences can be one to two orders of magnitude lower than overall conjugated proteins while possessing specific cellular recognition. In addition, we found that common conjugation strategies lead to a large excess of non-specifically compared to covalently bound ligands and instabilities that may impact targeting. These can be avoided by certain synthetic conditions presented here for effective exploitation of multivalent surfaces in nanomedicine.
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A wide range of particles have been developed for different applications in drug-delivery, tissue engineering, or regenerative medicine. In contrast to traditional spherical particles, nonspherical (e.g., cylindrical) particles possess several structural and morphological advantages that make them attractive for specific applications. Here, we developed a top-down approach to process electrospun fibers into microsized cylinders (i.e., microcylinders) with high specific surface area and with or without surface porosity. To obtain these microcylinders, poly(l-lactic acid) (PLLA) solutions were subjected to electrospinning, followed by an aminolysis-based chemical scission procedure. The morphology, structure, and chemical composition of the microcylinders were then characterized. The specific surface area and surface porosity of the microcylinders were controlled by the volatility of the solvents, and their length was dependent on the duration of the aminolysis reaction. During aminolysis, the microcylinders became functionalized with amine groups, enabling potential further modifications by grafting with compounds containing desired chemical groups, for example, carboxyl, carbonyl, or hydroxyl functional groups. Additionally, the microcylinders showed in vitro biocompatible properties related to cell viability. These data demonstrate that PLLA microcylinders with high specific surface area, optional surface porosity, amine-based functional handles granting additional functionalization, and cytocompatible properties are candidate materials for future biomedical applications.
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The aim of this study is to verify if water-soluble porphyrins can be used as proteasome inhibitors. We have found that cationic porphyrins inhibit proteasome peptidase activities much more effectively than the corresponding anionic derivatives. The relevance of electrostatics in driving porphyin-proteasome interactions has been confirmed by the observation that the inhibitory efficiency of the cationic macrocycles decreases with the number of positive substituents. We have also investigated various metalloporphyrins, which differ due to the different propension of the central metal ion toward axial coordination. Our experimental results indicate that the naked cationic porphyrins are the most active in reversibly inhibiting the three main protease activities of the proteasome in the micromolar range. A spectroscopic characterization of porphyrin-proteasome interactions by UV-vis spectra parallels the results of inhibition assays: the higher the inhibitory effect the stronger the spectroscopic variations are. To interpret the action of porphyrins at a molecular level, we have performed calculations evidencing that cationic porphyrins may hinder the access to the canonical proteolytic site on the proteasome ß5 subunit. In particular, an inspection of the top-scoring docking modes shows that the tetracationic porphyrin blocks the catalytic pocket, close to the N termini of the ß5 proteasome subunit, more efficiently than its anionic counterpart. Proteasome inhibition activity of porphyrins unites their known anticancer properties making them suitable as a scaffold for the design of novel multitargeted molecules.
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Porfirinas/farmacologia , Inibidores de Proteassoma , Cátions/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Células HeLa , Humanos , Modelos MolecularesRESUMO
The interaction between native calf thymus deoxyribonucleic acid (DNA) and Fe(III)- N ,N'-ethylene-bis (salicylideneiminato)-chloride, Fe(Salen)Cl, was investigated in aqueous solutions by UV-visible (UV-vis) absorption, circular dichroism (CD), thermal denaturation and viscosity measurements. The results obtained from CD, UV-vis and viscosity measurements exclude DNA intercalation and can be interpreted in terms of an electrostatic binding between the Fe(Salen)(+) cation and the phosphate groups of DNA. The trend of the UV-vis absorption band of the Fe(Salen)Cl complex at different ratios [DNA(phosphate)]/[Fe(Salen)Cl] and the large increase of the melting temperature of DNA in the presence of Fe(Salen)Cl, support the hypothesis of an external electrostatic interaction between the negatively charged DNA double helix and the axially stacked positively charged Fe(Salen)(+) moieties, analogously to what reported for a number of porphyrazines and metal-porphyrazine complexes interacting with DNA.
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DNA/química , Compostos Férricos/química , Bases de Schiff/química , Animais , Bovinos , Dicroísmo Circular , Isótopos de Ferro , Desnaturação de Ácido Nucleico , Análise Espectral , ViscosidadeRESUMO
Molecular defects affecting the ATRX gene lead to the ATRX syndrome (alpha thalassemia/mental retardation syndrome, X-linked), characterized by severe mental retardation, microcephaly, distinct facial dysmorphism, and genital abnormalities, as well as a wide spectrum of other pathological features. Alpha thalassemia is frequent but does not represent a constant characteristic of the syndrome. An expanding phenotype of the ATRX gene (a RAD54 homologue encoding a putative zinc-finger helicase) has been demonstrated as a result of the association of single mutations with specific X-linked mental retardation syndromes. To date, mutational analysis of the gene has been based on direct DNA sequencing or using methods with a lower detection rate. In this paper, we present a broad-range DGGE method for single-step mutation scanning of the entire open reading frame (ORF) and canonical splice sites of the gene. Using this method, we successfully identified five novel sequence changes in the ATRX gene, including four missense mutations (K1733E, R2085C, D2136N, T2169A) and one polymorphism (IVS5+35G>A).