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1.
Anal Chem ; 96(23): 9468-9477, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38821490

RESUMO

Leukemia comprises a diverse group of bone marrow tumors marked by cell proliferation. Current diagnosis involves identifying leukemia subtypes through visual assessment of blood and bone marrow smears, a subjective and time-consuming method. Our study introduces the characterization of different leukemia subtypes using a global clustering approach of Raman hyperspectral maps of cells. We analyzed bone marrow samples from 19 patients, each presenting one of nine distinct leukemia subtypes, by conducting high spatial resolution Raman imaging on 319 cells, generating over 1.3 million spectra in total. An automated preprocessing pipeline followed by a single-step global clustering approach performed over the entire data set identified relevant cellular components (cytoplasm, nucleus, carotenoids, myeloperoxidase (MPO), and hemoglobin (HB)) enabling the unsupervised creation of high-quality pseudostained images at the single-cell level. Furthermore, this approach provided a semiquantitative analysis of cellular component distribution, and multivariate analysis of clustering results revealed the potential of Raman imaging in leukemia research, highlighting both advantages and challenges associated with global clustering.


Assuntos
Leucemia , Análise Espectral Raman , Análise Espectral Raman/métodos , Humanos , Leucemia/patologia , Análise por Conglomerados , Peroxidase/metabolismo
2.
Int J Mol Sci ; 25(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38256215

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder affecting about 10 million people worldwide with a prevalence of about 2% in the over-80 population. The disease brings in also a huge annual economic burden, recently estimated by the Michael J Fox Foundation for Parkinson's Research to be USD 52 billion in the United States alone. Currently, no effective cure exists, but available PD medical treatments are based on symptomatic prescriptions that include drugs, surgical approaches and rehabilitation treatment. Due to the complex biology of a PD brain, the design of clinical trials and the personalization of treatment strategies require the identification of accessible and measurable biomarkers to monitor the events induced by treatment and disease progression and to predict patients' responsiveness. In the present review, we strive to briefly summarize current knowledge about PD biomarkers, focusing on the role of extracellular vesicles as active or involuntary carriers of disease-associated proteins, with particular attention to those research works that envision possible clinical applications.


Assuntos
Vesículas Extracelulares , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Biomarcadores , Encéfalo , Progressão da Doença
3.
Analyst ; 148(23): 6070-6077, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37904570

RESUMO

The application of liposomes (LPs) to central nervous system disorders could represents a turning point in the therapy and quality of life of patients. Indeed, LPs have demonstrated their ability to cross the blood-brain barrier (BBB) and, as a consequence, to enhance the therapeutics delivery into the brain. Some approaches for BBB crossing involve the modification of LP surfaces with biologically active ligands. Among them, the Apolipoprotein E-modified peptide (mApoE) has been used for several LP-based nanovectors under investigation. In this study, we propose Surface Plasmon Resonance imaging (SPRi) for the characterization of multifunctionalized LPs for Glioblastoma treatment. LPs were functionalized with mApoE and with a metallo-protease sensitive lipopeptide to deliver and guarantee the localized release of an encapsulated drug in diseased areas. The SPRi analysis was optimized in order to evaluate the binding affinity between LPs and mApoE receptors, finding that mApoE-LPs generated SPRi signals referred to interactions between mApoE and receptors mainly present in the brain. Moreover, a significant binding between LPs and VCAM-1 (endothelial receptor) was observed, whereas LPs did not interact significantly with peripheral receptors expressed on monocytes and lymphocytes. SPRi results confirmed not only the presence of mApoE on LP surfaces, but also its binding affinity, thanks to the specific interaction with selected receptors. In conclusion, the high sensitivity and the multiplexing capability associated with the low volumes of sample required and the minimal sample preparation, make SPRi an excellent technique for the characterization of multifunctionalized nanoparticles-based formulations.


Assuntos
Encefalopatias , Lipossomos , Humanos , Lipopolissacarídeos , Qualidade de Vida , Ressonância de Plasmônio de Superfície , Sistemas de Liberação de Medicamentos
4.
Int J Mol Sci ; 24(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36768820

RESUMO

Glioblastoma multiforme (GBM) is the most common malignant brain tumor, associated with low long-term survival. Nanoparticles (NPs) developed against GBM are a promising strategy to improve current therapies, by enhancing the brain delivery of active molecules and reducing off-target effects. In particular, NPs hold high potential for the targeted delivery of chemotherapeutics both across the blood-brain barrier (BBB) and specifically to GBM cell receptors, pathways, or the tumor microenvironment (TME). In this review, the most recent strategies to deliver drugs to GBM are explored. The main focus is on how surface functionalizations are essential for BBB crossing and for tumor specific targeting. We give a critical analysis of the various ligand-based approaches that have been used to target specific cancer cell receptors and the TME, or to interfere with the signaling pathways of GBM. Despite the increasing application of NPs in the clinical setting, new methods for ligand and surface characterization are needed to optimize the synthesis, as well as to predict their in vivo behavior. An expert opinion is given on the future of this research and what is still missing to create and characterize a functional NP system for improved GBM targeting.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanopartículas , Humanos , Glioblastoma/metabolismo , Ligantes , Nanopartículas/uso terapêutico , Transporte Biológico , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Barreira Hematoencefálica/metabolismo , Sistemas de Liberação de Medicamentos , Microambiente Tumoral
5.
Int J Mol Sci ; 24(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175644

RESUMO

The inflammatory, reparative and regenerative mechanisms activated in ischemic stroke patients immediately after the event cooperate in the response to injury, in the restoration of functions and in brain remodeling even weeks after the event and can be sustained by the rehabilitation treatment. Nonetheless, patients' response to treatments is difficult to predict because of the lack of specific measurable markers of recovery, which could be complementary to clinical scales in the evaluation of patients. Considering that Extracellular Vesicles (EVs) are carriers of multiple molecules involved in the response to stroke injury, in the present study, we have identified a panel of EV-associated molecules that (i) confirm the crucial involvement of EVs in the processes that follow ischemic stroke, (ii) could possibly profile ischemic stroke patients at the beginning of the rehabilitation program, (iii) could be used in predicting patients' response to treatment. By means of a multiplexing Surface Plasmon Resonance imaging biosensor, subacute ischemic stroke patients were proven to have increased expression of vascular endothelial growth factor receptor 2 (VEGFR2) and translocator protein (TSPO) on the surface of small EVs in blood. Besides, microglia EVs and endothelial EVs were shown to be significantly involved in the intercellular communications that occur more than 10 days after ischemic stroke, thus being potential tools for the profiling of patients in the subacute phase after ischemic stroke and in the prediction of their recovery.


Assuntos
Técnicas Biossensoriais , Vesículas Extracelulares , AVC Isquêmico , Humanos , AVC Isquêmico/diagnóstico , AVC Isquêmico/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Biomarcadores/metabolismo , Vesículas Extracelulares/metabolismo , Receptores de GABA/metabolismo
6.
Arch Phys Med Rehabil ; 101(5): 917-923, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32035141

RESUMO

The growing field of regenerative rehabilitation has great potential to improve clinical outcomes for individuals with disabilities. However, the science to elucidate the specific biological underpinnings of regenerative rehabilitation-based approaches is still in its infancy and critical questions regarding clinical translation and implementation still exist. In a recent roundtable discussion from International Consortium for Regenerative Rehabilitation stakeholders, key challenges to progress in the field were identified. The goal of this article is to summarize those discussions and to initiate a broader discussion among clinicians and scientists across the fields of regenerative medicine and rehabilitation science to ultimately progress regenerative rehabilitation from an emerging field to an established interdisciplinary one. Strategies and case studies from consortium institutions-including interdisciplinary research centers, formalized courses, degree programs, international symposia, and collaborative grants-are presented. We propose that these strategic directions have the potential to engage and train clinical practitioners and basic scientists, transform clinical practice, and, ultimately, optimize patient outcomes.


Assuntos
Medicina Regenerativa/tendências , Reabilitação/tendências , Certificação , Congressos como Assunto , Currículo , Bolsas de Estudo , Humanos , Medicina Regenerativa/educação , Reabilitação/educação
7.
Anal Bioanal Chem ; 411(9): 1873-1885, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30155701

RESUMO

Here we describe a simple approach for the simultaneous detection of multiple microRNAs (miRNAs) using a single nanostructured reagent as surface plasmon resonance imaging (SPRi) enhancer and without using enzymatic reactions, sequence specific enhancers or multiple enhancing steps as normally reported in similar studies. The strategy involves the preparation and optimisation of neutravidin-coated gold nanospheres (nGNSs) functionalised with a previously biotinylated antibody (Ab) against DNA/RNA hybrids. The Ab guarantees the recognition of any miRNA sequence adsorbed on a surface properly functionalised with different DNA probes; at the same time, gold nanoparticles permit to detect this interaction, thus producing enough SPRi signal even at a low ligand concentration. After a careful optimisation of the nanoenhancer and after its characterisation, the final assay allowed the simultaneous detection of four miRNAs with a limit of detection (LOD) of up to 0.5 pM (equal to 275 attomoles in 500 µL) by performing a single enhancing injection. The proposed strategy shows good signal specificity and permits to discriminate wild-type, single- and triple-mutated sequences much better than non-enhanced SPRi. Finally, the method works properly in complex samples (total RNA extracted from blood) as demonstrated by the detection of four miRNAs potentially related to multiple sclerosis used as case study. This proof-of-concept study confirms that the approach provides the possibility to detect a theoretically unlimited number of miRNAs using a simple protocol and an easily prepared enhancing reagent, and may further facilitate the development of affordable multiplexing miRNA screening for clinical purposes.


Assuntos
MicroRNAs/análise , Ressonância de Plasmônio de Superfície/métodos , Adsorção , DNA/química , Enzimas/química , Indicadores e Reagentes/química , Dispositivos Lab-On-A-Chip , Ligantes , Limite de Detecção , MicroRNAs/química , Microscopia Eletrônica de Varredura , Hibridização de Ácido Nucleico , Estudo de Prova de Conceito , Propriedades de Superfície
8.
Nanomedicine ; 22: 102097, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31648040

RESUMO

Parkinson's disease (PD) is a chronic neurodegenerative disorder, characterized by considerable clinical heterogeneity. Extracellular vesicles (EVs) were proposed as new biomarkers for PD because of their role as vehicles of multiple PD related molecules, but technical limitations exist in their detection and characterization in a clinical environment. We propose herein a Raman based protocol for the label-free analysis of circulating EVs as diagnostic and predictive tool for PD. After purification from serum of PD patients and healthy subjects, EVs were analyzed by Raman spectroscopy demonstrating the feasibility and reproducibility of the proposed biophotonic approach, its moderate accuracy in distinguishing PD patients from controls by their EV profile and the correlation between Raman data and clinical scales. Once validated, the Raman spectroscopy of circulating EVs could represent a reliable, automatable and sensitive method for the stratification of PD patients and for the evaluation of the effectiveness of rehabilitation and pharmacological treatments.


Assuntos
Vesículas Extracelulares/metabolismo , Doença de Parkinson/diagnóstico , Análise Espectral Raman , Idoso , Idoso de 80 Anos ou mais , Vesículas Extracelulares/ultraestrutura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal
9.
Anal Chem ; 90(15): 8873-8880, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29972017

RESUMO

The use of exosomes for diagnostic and disease monitoring purposes is becoming particularly appealing in biomedical research because of the possibility to study directly in biological fluids some of the features related to the organs from which exosomes originate. A paradigmatic example are brain-derived exosomes that can be found in plasma and used as a direct read-out of the status of the central nervous system (CNS). Inspired by recent remarkable development of plasmonic biosensors, we have designed a surface plasmon resonance imaging (SPRi) assay that, taking advantage of the fact that exosome size perfectly fits within the surface plasmon wave depth, allows the detection of multiple exosome subpopulations of neural origin directly in blood. By use of an array of antibodies, exosomes derived from neurons and oligodendrocytes were isolated and detected with good sensitivity. Subsequently, by injecting a second antibody on the immobilized vesicles, we were able to quantify the amount of CD81 and GM1, membrane components of exosomes, on each subpopulation. In this way, we have been able to demonstrate that they are not homogeneously expressed but exhibit a variable abundance according to the exosome cellular origin. These results confirm the extreme variability of exosome composition and demonstrate how SPRi can provide an effective tool for their characterization. Besides, our work paves the road toward more precise clinical studies on the use of exosomes as potential biomarkers of neurodegenerative diseases.


Assuntos
Encéfalo/citologia , Exossomos/química , Neurônios/química , Oligodendroglia/química , Plasma/química , Ressonância de Plasmônio de Superfície/métodos , Adulto , Anticorpos Imobilizados/química , Feminino , Gangliosídeo G(M1)/análise , Humanos , Masculino , Tetraspanina 28/análise
10.
Comput Biol Med ; 171: 108028, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38335817

RESUMO

Raman Spectroscopy promises the ability to encode in spectral data the significant differences between biological samples belonging to patients affected by a disease and samples of healthy patients (controls). However, the decoding and interpretation of the Raman spectral fingerprint is still a difficult and time-consuming procedure even for domain experts. In this work, we test an end-to-end deep-learning diagnostic pipeline able to classify spectral data from saliva samples. The pipeline has been validated against the SARS-COV-2 Infection and for the screening of neurodegenerative diseases such as Parkinson's and Alzheimer's diseases. The proposed system can be used for the fast prototyping of promising non-invasive, cost and time-efficient diagnostic screening tests.


Assuntos
Doença de Alzheimer , COVID-19 , Humanos , Saliva , Aprendizado de Máquina , COVID-19/diagnóstico , Teste para COVID-19
11.
Contemp Clin Trials ; 136: 107415, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38114046

RESUMO

BACKGROUND: Heart transplant (HTx) is gold-standard therapy for patients with end-stage heart failure. Cardiac rehabilitation (CR) is a multidisciplinary intervention shown to improve cardiovascular prognosis and quality of life. The aim in this randomized controlled trial is to explore the safety and efficacy of cardiac telerehabilitation after HTx. In addition, biomarkers of rehabilitation outcomes will be identified, as data that will enable treatment to be tailored to patient phenotype. METHODS: Patients after HTx will be recruited at IRCCS S. Maria Nascente - Fondazione Don Gnocchi, Milan, Italy (n = 40). Consenting participants will be randomly allocated to either of two groups (1:1): an intervention group who will receive on-site CR followed by 12 weeks of telerehabilitation, or a control group who will receive on-site CR followed by standard homecare and exercise programme. Recruitment began on 20th May 2023 and is expected to continue until 20th May 2025. Socio-demographic characteristics, lifestyle, health status, cardiovascular events, cognitive function, anxiety and depression symptoms, and quality of life will be assessed, as well as exercise capacity and muscular endurance. Participants will be evaluated before the intervention, post-CR and after 6 months. In addition, analysis of circulating extracellular vesicles using Surface Plasmon Resonance imaging (SPRi), based on a rehabilomic approach, will be applied to both groups pre- and post-CR. CONCLUSION: This study will explore the safety and efficacy of cardiac telerehabilitation after HTx. In addition, a rehabilomic approach will be used to investigate biomolecular phenotypization in HTx patients. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT05824364.


Assuntos
Reabilitação Cardíaca , Transplante de Coração , Telerreabilitação , Humanos , Qualidade de Vida , Telerreabilitação/métodos , Exercício Físico , Reabilitação Cardíaca/métodos , Terapia por Exercício/métodos , Sistema de Registros
12.
Front Neurol ; 15: 1338609, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327625

RESUMO

Background: Intensive treadmill training (TT) has been documented to improve gait parameters and functional independence in Parkinson's Disease (PD), but the optimal intervention protocol and the criteria for tailoring the intervention to patients' performances are lacking. TT may be integrated with augmented virtual reality (AVR), however, evidence of the effectiveness of this combined treatment is still limited. Moreover, prognostic biomarkers of rehabilitation, potentially useful to customize the treatment, are currently missing. The primary aim of this study is to compare the effects on gait performances of TT + AVR versus TT alone in II-III stage PD patients with gait disturbance. Secondary aims are to assess the effects on balance, gait parameters and other motor and non-motor symptoms, and patient's satisfaction and adherence to the treatment. As an exploratory aim, the study attempts to identify biomarkers of neuroplasticity detecting changes in Neurofilament Light Chain concentration T0-T1 and to identify prognostic biomarkers associated to blood-derived Extracellular Vesicles. Methods: Single-center, randomized controlled single-blind trial comparing TT + AVR vs. TT in II-III stage PD patients with gait disturbances. Assessment will be performed at baseline (T0), end of training (T1), 3 (T2) and 6 months (T3, phone interview) from T1. The primary outcome is difference in gait performance assessed with the Tinetti Performance-Oriented Mobility Assessment gait scale at T1. Secondary outcomes are differences in gait performance at T2, in balance and spatial-temporal gait parameters at T1 and T2, patients' satisfaction and adherence. Changes in falls, functional mobility, functional autonomy, cognition, mood, and quality of life will be also assessed at different timepoints. The G*Power software was used to estimate a sample size of 20 subjects per group (power 0.95, α < 0.05), raised to 24 per group to compensate for potential drop-outs. Both interventions will be customized and progressive, based on the participant's performance, according to a predefined protocol. Conclusion: This study will provide data on the possible superiority of AVR-associated TT over conventional TT in improving gait and other motor and non-motor symptoms in persons with PD and gait disturbances. Results of the exploratory analysis could add information in the field of biomarker research in PD rehabilitation.

13.
Exp Gerontol ; 177: 112179, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37087025

RESUMO

Exercise promotes healthy aging of skeletal muscle. This benefit may be mediated by youthful factors in the circulation released in response to an exercise protocol. While numerous studies to date have explored soluble proteins as systemic mediators of rejuvenating effect of exercise on tissue function, here we showed that the beneficial effect of skeletal muscle contractile activity on aged muscle function is mediated, at least in part, by regenerative properties of circulating extracellular vesicles (EVs). Muscle contractile activity elicited by neuromuscular electrical stimulation (NMES) decreased intensity of expression of the tetraspanin surface marker, CD63, on circulating EVs. Moreover, NMES shifted the biochemical Raman fingerprint of circulating EVs in aged animals with significant changes in lipid and sugar content in response to NMES when compared to controls. As a demonstration of the physiological relevance of these EV changes, we showed that intramuscular administration of EVs derived from aged animals subjected to NMES enhanced aged skeletal muscle healing after injury. These studies suggest that repetitive muscle contractile activity enhances the regenerative properties of circulating EVs in aged animals.


Assuntos
Vesículas Extracelulares , Músculo Esquelético , Animais , Músculo Esquelético/fisiologia , Contração Muscular , Exercício Físico , Estimulação Elétrica/métodos
14.
Nanomaterials (Basel) ; 13(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36839067

RESUMO

The characterization of nanoparticle-based drug-delivery systems represents a crucial step in achieving a comprehensive overview of their physical, chemical, and biological features and evaluating their efficacy and safety in biological systems. We propose Raman Spectroscopy (RS) for the characterization of liposomes (LPs) to be tested for the control of neuroinflammation and microglial dysfunctions in Glioblastoma multiforme and Alzheimer's disease. Drug-loaded LPs were functionalized to cross the blood-brain barrier and to guarantee localized and controlled drug release. The Raman spectra of each LP component were used to evaluate their contribution in the LP Raman fingerprint. Raman data analysis made it possible to statistically discriminate LPs with different functionalization patterns, showing that each molecular component has an influence in the Raman spectrum of the final LP formulation. Moreover, CLS analysis on Raman data revealed a good level of synthetic reproducibility of the formulations and confirmed their stability within one month from their synthesis, demonstrating the ability of the technique to evaluate the efficacy of LP synthesis using small amount of sample. RS represents a valuable tool for a fast, sensitive and label free biochemical characterization of LPs that could be used for quality control of nanoparticle-based therapeutics.

15.
Biology (Basel) ; 12(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36829504

RESUMO

Extracellular vesicles (EVs) are natural nanoparticles secreted under physiological and pathological conditions. Thanks to their diagnostic potential, EVs are increasingly being studied as biomarkers of a variety of diseases, including neurological disorders. To date, most studies on EV biomarkers use blood as the source, despite different disadvantages that may cause an impure isolation of the EVs. In the present article, we propose the use of saliva as a valuable source of EVs that could be studied as biomarkers in an easily accessible biofluid. Using a comparable protocol for the isolation of EVs from both liquid biopsies, salivary EVs showed greater purity in terms of co-isolates (evaluated by nanoparticle tracking analysis and Conan test). In addition, Raman spectroscopy was used for the identification of the overall biochemical composition of EVs coming from the two different biofluids. Even considering the limited amount of EVs that can be isolated from saliva, the use of Raman spectroscopy was not hampered, and it was able to provide a comprehensive characterization of EVs in a high throughput and repeatable manner. Raman spectroscopy can thus represent a turning point in the application of salivary EVs in clinics, taking advantage of the simple method of collection of the liquid biopsy and of the quick, sensitive and label-free biophotonics-based approach.

16.
ACS Nano ; 17(20): 19640-19651, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37797946

RESUMO

Skeletal muscle regeneration relies on the tightly temporally regulated lineage progression of muscle stem/progenitor cells (MPCs) from activation to proliferation and, finally, differentiation. However, with aging, MPC lineage progression is disrupted and delayed, ultimately causing impaired muscle regeneration. Extracellular vesicles (EVs) have attracted broad attention as next-generation therapeutics for promoting tissue regeneration. As a next step toward clinical translation, strategies to manipulate EV effects on downstream cellular targets are needed. Here, we developed an engineering strategy to tune the therapeutic potential of EVs using nanotopographical cues. We found that EVs released by young MPCs cultured on flat substrates (fEVs) promoted the proliferation of aged MPCs while EVs released by MPCs cultured on nanogratings (nEVs) promoted myogenic differentiation. We then employed a bioengineered 3D muscle aging model to optimize the administration protocol and test the therapeutic potential of fEVs and nEVs in a high-throughput manner. We found that the sequential administration first of fEVs during the phase of MPC proliferative expansion (i.e., 1 day after injury) followed by nEV administration at the stage of MPC differentiation (i.e., 3 days after injury) enhanced aged muscle regeneration to a significantly greater extent than fEVs and nEVs delivered either in isolation or mixed. The beneficial effects of the sequential EV treatment strategy were further validated in vivo, as evidenced by increased myofiber size and improved functional recovery. Collectively, our study demonstrates the ability of topographical cues to tune EV therapeutic potential and highlights the importance of optimizing the EV administration strategy to accelerate aged skeletal muscle regeneration.


Assuntos
Sinais (Psicologia) , Vesículas Extracelulares , Células Cultivadas , Músculo Esquelético , Diferenciação Celular
17.
Pharmaceutics ; 15(9)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37765332

RESUMO

The progression of Alzheimer's disease (AD) correlates with the propagation of hyperphosphorylated tau (pTau) from the entorhinal cortex to the hippocampus and neocortex. Neutral sphingomyelinase2 (nSMase2) is critical in the biosynthesis of extracellular vesicles (EVs), which play a role in pTau propagation. We recently conjugated DPTIP, a potent nSMase2 inhibitor, to hydroxyl-PAMAM-dendrimer nanoparticles that can improve brain delivery. We showed that dendrimer-conjugated DPTIP (D-DPTIP) robustly inhibited the spread of pTau in an AAV-pTau propagation model. To further evaluate its efficacy, we tested D-DPTIP in the PS19 transgenic mouse model. Unexpectantly, D-DPTIP showed no beneficial effect. To understand this discrepancy, we assessed D-DPTIP's brain localization. Using immunofluorescence and fluorescence-activated cell-sorting, D-DPTIP was found to be primarily internalized by microglia, where it selectively inhibited microglial nSMase2 activity with no effect on other cell types. Furthermore, D-DPTIP inhibited microglia-derived EV release into plasma without affecting other brain-derived EVs. We hypothesize that microglial targeting allowed D-DPTIP to inhibit tau propagation in the AAV-hTau model, where microglial EVs play a central role in propagation. However, in PS19 mice, where tau propagation is independent of microglial EVs, it had a limited effect. Our findings confirm microglial targeting with hydroxyl-PAMAM dendrimers and highlight the importance of understanding cell-specific mechanisms when designing targeted AD therapies.

18.
Exp Dermatol ; 21(7): 549-51, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22716254

RESUMO

Tumor Necrosis Factor-α (TNF-α) plays a pivotal role in psoriasis, an immuno-mediated and genetic skin disease. Anti-TNF-α inhibitors, such as etanercept, are widely used in clinical practice. By immunofluorescence, we investigated the expression of junctional transmembrane proteins in desmosomes (desmocollin-1, Dsc1; desmoglein-1, Dsg1), adherens junctions (E-cadherin), tight junctions (occludin), biomarkers of keratinocyte differentiation (keratin-10, K10; keratin-14, K14; keratin-16, K16; involucrin), epithelial proliferation and apoptosis in psoriatic skin before/after etanercept treatment (n = 5) and in control skin samples (n = 5). Occludin, K14, K16 and involucrin expressions were altered in psoriatic epidermis, while Dsc1, Dsg1, E-cadherin and K10 localisations were comparable to controls. Etanercept promoted the restoration of the physiological condition as suggested by a more differentiated keratinocyte phenotype and a reduced epidermal proliferation rate.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Imunoglobulina G/uso terapêutico , Psoríase/tratamento farmacológico , Psoríase/patologia , Receptores do Fator de Necrose Tumoral/uso terapêutico , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose , Caderinas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Desmocolinas/metabolismo , Desmogleína 1/metabolismo , Desmossomos/metabolismo , Etanercepte , Feminino , Humanos , Imunoglobulina G/farmacologia , Queratina-10/metabolismo , Queratina-14/metabolismo , Queratina-16/metabolismo , Queratinócitos/efeitos dos fármacos , Ocludina/metabolismo , Fenótipo , Precursores de Proteínas/metabolismo , Psoríase/metabolismo , Junções Íntimas , Fator de Necrose Tumoral alfa/antagonistas & inibidores
19.
Children (Basel) ; 9(2)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35204908

RESUMO

Children affected by orofacial disorders mix functional alterations with morphological problems, and suitable techniques should be devised for their analysis. Stereophotogrammetry and 3D-3D facial superimposition have already proven to reliably assess morphological differences even between twin siblings, separating the effect of genetic and environmental factors. However, little information is available about twin babies. We longitudinally analyzed a couple of healthy monozygotic twin sisters aged 6 months to 5 years (height time points). The entire 3D facial models of the two sisters were registered according to the least point-to-point distance, and the relevant RMS (root mean square) distance between the facial models was calculated at each time and compared with reference data recorded from adult twins (Mann-Whitney test, p < 0.05). RMS values in the twin sisters were on average 1.18 ± 0.21 mm, and 1.86 ± 0.53 mm in adults, with a significant difference (p < 0.01). Results showed that twins are more similar in early childhood when environmental factors are supposed to have not influenced facial morphology sufficiently. Additionally, the technique seems adequate to detect even small differences: the faces of the twin sisters were not fully identical. 3D-3D facial superimposition techniques can objectively quantify facial dissimilarity even in monozygotic twins. The method may be applied to the faces of twins discordant for some orofacial and maxillofacial pathology and potentially separate genetic and environmental factors.

20.
Biology (Basel) ; 10(9)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34571720

RESUMO

Patients that survive after a stroke event may present disabilities that can persist for a long time or permanently after it. If stroke prevention fails, the prompt and combinatorial intervention with pharmacological and rehabilitation therapy is pivotal for the optimal recovery of patients and the reduction of disabilities. In the present review, we summarize some key features of the complex events that occur in the brain during and after the stroke event, with a special focus on extracellular vesicles (EVs) and their role as both carriers of biomarkers and potential therapeutics. EVs have already demonstrated their ability to be used for diagnostic purposes for multiple brain disorders and could represent valuable tools to track the regenerative and inflammatory processes occurring in the injured brain after stroke. Last, but not least, the use of artificial or stem cell-derived EVs were proved to be effective in stimulating brain remodeling and ameliorating recovery after stroke. Still, effective biomarkers of recovery are needed to design robust trials for the validation of innovative therapeutic strategies, such as regenerative rehabilitation approaches.

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