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1.
PLoS One ; 13(5): e0195891, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29768414

RESUMO

BACKGROUND: Currently available treatments for secondary progressive multiple sclerosis(SPMS) have limited efficacy and/or safety concerns. Adipose-mesenchymal derived stem cells(AdMSCs) represent a promising option and can be readily obtained using minimally invasive procedures. PATIENTS AND METHODS: In this triple-blind, placebo-controlled study, cell samples were obtained from consenting patients by lipectomy and subsequently expanded. Patients were randomized to a single infusion of placebo, low-dose(1x106cells/kg) or high-dose(4x106cells/kg) autologous AdMSC product and followed for 12 months. Safety was monitored recording adverse events, laboratory parameters, vital signs and spirometry. Expanded disability status score (EDSS), magnetic-resonance-imaging, and other measures of possible treatment effects were also recorded. RESULTS: Thirty-four patients underwent lipectomy for AdMSCs collection, were randomized and thirty were infused (11 placebo, 10 low-dose and 9 high-dose); 4 randomized patients were not infused because of karyotype abnormalities in the cell product. Only one serious adverse event was observed in the treatment arms (urinary infection, considered not related to study treatment). No other safety parameters showed changes. Measures of treatment effect showed an inconclusive trend of efficacy. CONCLUSION: Infusion of autologous AdMSCs is safe and feasible in patients with SPMS. Larger studies and probably treatment at earlier phases would be needed to investigate the potential therapeutic benefit of this technique.


Assuntos
Tecido Adiposo/citologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Esclerose Múltipla Crônica Progressiva/terapia , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
2.
J Mol Neurosci ; 41(1): 114-20, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19844808

RESUMO

A major determinant in the pathogenesis of Alzheimer's disease (AD) is the deposition of beta-amyloid (Abeta) peptides in specific areas of the central nervous system. Therefore, animal models of Alzheimer amyloidosis are excellent tools to identify candidates to facilitate drug screening and to understand the molecular pathology of AD. Activity-dependent neuroprotective protein (ADNP) plays an essential role in brain development, and NAP (NAPVSIPQ, generic name: davunetide)--a peptide derived from ADNP--is currently in clinical development for the treatment of neurodegenerative disorders. However, the link between ADNP expression and AD remains unexplored. To test whether ADNP is affected by the onset of AD and progression, we employed the PS1xAPP mouse model (PS1(M146L) x APP(751SL) transgenic mice) to analyze the mRNA expression of ADNP in the hippocampus and cerebellum in early and advanced stages of disease. Results showed that ADNP expression in 6-month-old PS1xAPP mice hippocampus was higher than in wild-type (WT) mice. ADNP was originally identified as a vasoactive intestinal peptide (VIP)-responsive gene taking part in the VIP-mediated neurotrophic pathway. Interestingly, the expression of VIP was not affected in the same experimental setting, suggesting that ADNP expression is a VIP-independent marker associated with AD. Moreover, in the cerebellum, a brain area not affected by Abeta deposition, ADNP mRNA expression in 6-month-old PS1xAPP and WT were not different. A similar extent of hippocampal ADNP expression was observed in 18-month-old WT and PS1xAPP mice, in contrast to the differential expression level at 6 months of age. However, hippocampal ADNP expression in both WT and PS1xAPP was increased with aging similar to VIP mRNA expression. Our findings support the hypothesis that ADNP expression is related to early or mild AD progression by a VIP-independent mechanism.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Presenilina-1/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Modelos Animais de Doenças , Hipocampo/citologia , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Peptídeo Intestinal Vasoativo/metabolismo
3.
Nanomedicine (Lond) ; 4(8): 919-30, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19958228

RESUMO

UNLABELLED: We characterized a method to conjugate functional silver nanoparticles with vasoactive intestinal peptide (VIP), which could be used as a working model for further tailor-made applications based on VIP surface functionality. Despite sustained interest in the therapeutic applications of VIP, and the fact that its drugability could be largely improved by the attachament to functionalized metal nanoparticles, no methods have been described so far to obtain them. MATERIALS & METHODS: VIP was conjugated to tiopronin-capped silver nanoparticles of a narrow size distribution, by means of proper linkers, to obtain VIP functionalized silver nanoparticles with two different VIP orientations (Ag-tiopronin-PEG-succinic-[His]VIP and Ag-tiopronin-PEG-VIP[His]). VIP intermediate nanoparticles were characterized by transmission-electron microscopy and Fourier transform infrared spectroscopy. VIP functionalized silver nanoparticles cytotoxicity was determined by lactate dehydrogenase release from mixed glial cultures prepared from cerebral cortices of 1-3 days-old C57/Bl mice. Cells were used for lipopolysaccharide stimulation at day 18-22 of culture. RESULTS: Two different types of VIP-functionalized silver nanoparticles were obtained; both expose the C-terminal part of the neuropeptide, but in the first type VIP is attached to silver nanoparticle through its free amine terminus (Ag-tiopronin-PEG-succinic-[His]VIP), while in the second type, VIP N-terminus remains free (Ag-tiopronin-PEG-VIP[His]). VIP-functionalized silver nanoparticles did not compromise cellular viability and inhibited microglia-induced stimulation under inflammatory conditions. CONCLUSION: The chemical synthesis procedure developed to obtain VIP-functionalized silver nanoparticles rendered functional products, in terms of biological activity. The two alternative orientations designed, reduced the constraints for chemical synthesis that depends on the nanosurface to be functionalized. Our study provides, for the first time, a proof of principle to enhance the therapeutic potential of VIP with the valuable properties of metal nanoparticles for imaging, targeting and drug delivery.


Assuntos
Nanopartículas Metálicas/química , Prata/química , Peptídeo Intestinal Vasoativo/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Imuno-Histoquímica , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Nanopartículas Metálicas/efeitos adversos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Nanotecnologia/métodos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Fator de Necrose Tumoral alfa/metabolismo
4.
EMBO J ; 28(23): 3758-70, 2009 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-19875982

RESUMO

The ATP-dependent protein chaperone heat-shock protein 70 (Hsp70) displays broad anti-aggregation functions and has a critical function in preventing protein misfolding pathologies. According to in vitro and in vivo models of Parkinson's disease (PD), loss of Hsp70 activity is associated with neurodegeneration and the formation of amyloid deposits of alpha-synuclein (alphaSyn), which constitute the intraneuronal inclusions in PD patients known as Lewy bodies. Here, we show that Hsp70 depletion can be a direct result of the presence of aggregation-prone polypeptides. We show a nucleotide-dependent interaction between Hsp70 and alphaSyn, which leads to the aggregation of Hsp70, in the presence of ADP along with alphaSyn. Such a co-aggregation phenomenon can be prevented in vitro by the co-chaperone Hip (ST13), and the hypothesis that it might do so also in vivo is supported by studies of a Caenorhabditis elegans model of alphaSyn aggregation. Our findings indicate that a decreased expression of Hip could facilitate depletion of Hsp70 by amyloidogenic polypeptides, impairing chaperone proteostasis and stimulating neurodegeneration.


Assuntos
Proteínas de Transporte/fisiologia , Proteínas de Choque Térmico HSP70/metabolismo , Homeostase/fisiologia , Complexos Multiproteicos/metabolismo , Doença de Parkinson/metabolismo , Proteínas Supressoras de Tumor/fisiologia , alfa-Sinucleína/metabolismo , Trifosfato de Adenosina/fisiologia , Amiloide/antagonistas & inibidores , Amiloide/biossíntese , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Proteínas de Transporte/antagonistas & inibidores , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Humanos , Chaperonas Moleculares , Complexos Multiproteicos/antagonistas & inibidores , Degeneração Neural/metabolismo , Degeneração Neural/prevenção & controle , Doença de Parkinson/etiologia , Peptídeos/antagonistas & inibidores , Peptídeos/fisiologia , Dobramento de Proteína , Estabilidade Proteica , Ratos , Proteínas Supressoras de Tumor/antagonistas & inibidores , alfa-Sinucleína/antagonistas & inibidores
5.
Nanomedicine (Lond) ; 3(5): 627-35, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18834270

RESUMO

AIMS: Capped silver nanoparticles that can be coupled to a variety of molecules and biomolecules are of great interest owing to their potential applications in biomedicine. However, there are no data about their toxicity or functional effects on a key innate immune response, such as IL-6 secretion, after the engagement of the main group of pathogen-associated molecular patterns receptors, that is, the Toll-like receptors (TLRs). MATERIALS & METHODS: N-(2-mercaptopropionyl)glycine (tiopronin)-capped silver (Ag@tiopronin) nanoparticles of a narrow sized distribution ( approximately 5 nm) were synthesized and characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, Raman, (1)H-NMR and total correlation spectroscopy. Cytotoxicity was determined by lactate deshidrogenase and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium assays in Raw 264.7 macrophages. IL-6 was measured by ELISA. RESULTS & DISCUSSION: Ag@tiopronin nanoparticles have a narrow size distribution ( approximately 5 nm), high solubility and stability in aqueous environment with no cytotoxicity in terms of mitochondrial function or plasma-membrane integrity at concentrations as high as 200 microg/10(6) cells. Ag@tiopronin nanoparticles were not proinflammatory agents, but remarkably they specifically impaired the IL-6 secretion mediated by TLR2, TLR2/6, TLR3 or TLR9 stimulation in co-treatment experiments. However, in pretreatment experiments, nanoparticles enhanced the susceptibility of macrophages to inflammatory stimulation mediated by TLR2/1 and TLR2/6 specific ligands while severely impairing the IL-6 secretion activated by the TLR3 or TLR9 ligands. CONCLUSIONS: Contrary to what is found for bare silver nanoparticles, Ag@tiopronin nanoparticles are noncytotoxic to macrophages. Ag@tiopronin nanoparticles showed differential effects on TLR signaling of a high degree of specificity, without proinflammatory effects by themselves. These effects have to be borne in mind when using bioconjugates of Ag@tiopronin nanoparticles for future medical applications.


Assuntos
Interleucina-6/metabolismo , Macrófagos/efeitos dos fármacos , Prata/farmacologia , Tiopronina/farmacologia , Receptores Toll-Like/metabolismo , Animais , Linhagem Celular , Macrófagos/citologia , Macrófagos/metabolismo , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Nanopartículas/ultraestrutura , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Receptor 2 Toll-Like/metabolismo , Receptor 3 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo
6.
Ann N Y Acad Sci ; 1070: 337-41, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16888188

RESUMO

Studies focused on the development of diabetes in NOD mice-a model for human type 1 diabetes-have revealed that an autoimmune inflammatory process is produced by the effect of Th1 cells and their secreted cytokines. DNA vaccination has been shown to be an effective method for modulating immunity in viral infections and experimental autoimmune diseases, including diabetes. VIP's immunomodulatory properties are partly mediated by skewing the pattern of cytokines from a proinflammatory response to an anti-inflammatory response. Using gene delivery to express VIP, we interfered in the immune process leading to diabetes in prone, cyclophosphamide-treated NOD mice. Our results extend the role of VIP in the control of immunoregulatory networks and open new perspectives for immunointervention through VIP-based gene therapy.


Assuntos
Plasmídeos/genética , Peptídeo Intestinal Vasoativo/genética , Animais , Diabetes Mellitus/genética , Diabetes Mellitus/prevenção & controle , Feminino , Técnicas de Transferência de Genes , Camundongos , Camundongos Endogâmicos NOD
7.
Ann N Y Acad Sci ; 1070: 500-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16888216

RESUMO

NAP is an eight-amino acid neuroprotective peptide NAPVSIPQ; it is the smallest active element derived from the recently cloned activity-dependent neuroprotective protein (ADNP). NAP readily enters the brain from the blood. It will be important to learn whether NAP, in addition to its neuroprotective activity, also might influence immune-mediated inflammation. Here, we report that: (a) macrophages express ADNP; (b) expression of ADNP in macrophages responds to VIP; and (c) NAP downregulates the key inflammatory cytokines tumor necrosis factor (TNF-alpha), interleukin-16 (IL-16), and IL-12 in macrophages. These findings indicate that ADNP/NAP can play an important role in immune regulation as well as in neuroprotection, which may be mutually related processes.


Assuntos
Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Fármacos Neuroprotetores/farmacologia , Oligopeptídeos/farmacologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Citocinas/metabolismo , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Fármacos Neuroprotetores/química , Oligopeptídeos/química
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