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1.
J Cell Mol Med ; 28(5): e18013, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386354

RESUMO

Plasminogen activator inhibitor-1 (PAI-1) impedes brain plasmin synthesis. Reduced plasmin activity facilitates cumulation of amyloid beta (Aß) in Alzheimer's disease (AD). Since plasmin also regulates the synaptic activity, it is possible that altered PAI-1 is present in other neurodegenerative disorders. We investigated whether PAI-1 and its counter-regulatory tissue plasminogen activator (tPA) are altered in serum of patients with dementia due to frontotemporal lobar degeneration (FTLD). Thirty five FTLD patients (21 in mild cognitive impairment stage (MCI) and 14 in dementia stage) and 10 cognitively healthy controls were recruited. Serum tPA and PAI-1 protein levels were measured by anova. Correlation between biochemical and demographic data were explored by measuring Pearson correlation coefficient. Serum PAI-1 levels were elevated in the FTLD dementia group as compared to FTLD MCI and controls. tPA serum levels and PAI-1/tPA ratio did not significantly differ among groups. There was a negative correlation between PAI-1 serum levels and disease severity measured by MMSE score. No correlations of tPA serum levels and PAI-1/tPA ratio with MMSE were found. Increased PAI-1 serum levels may serve as a marker of dementia in FTLD, suggesting that, besides Aß pathway, the plasmin system may affect cognition through synaptic activity.

2.
Hum Mol Genet ; 31(15): 2535-2547, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35220430

RESUMO

Epidermal development and maintenance are finely regulated events requiring a strict balance between proliferation and differentiation. Alterations in these processes give rise to human disorders such as cancer or syndromes with skin and annexes defects, known as ectodermal dysplasias (EDs). Here, we studied the functional effects of two novel receptor-interacting protein kinase 4 (RIPK4) missense mutations identified in siblings with an autosomal recessive ED with cutaneous syndactyly, palmoplantar hyperkeratosis and orofacial synechiae. Clinical overlap with distinct EDs caused by mutations in transcription factors (i.e. p63 and interferon regulatory factor 6, IRF6) or nectin adhesion molecules was noticed. Impaired activity of the RIPK4 kinase resulted both in altered epithelial differentiation and defective cell adhesion. We showed that mutant RIPK4 resulted in loss of PVRL4/nectin-4 expression in patient epidermis and primary keratinocytes, and demonstrated that PVRL4 is transcriptionally regulated by IRF6, a RIPK4 phosphorylation target. In addition, defective RIPK4 altered desmosome morphology through modulation of plakophilin-1 and desmoplakin. In conclusion, this work implicates RIPK4 kinase function in the p63-IRF6 regulatory loop that controls the proliferation/differentiation switch and cell adhesion, with implications in ectodermal development and cancer.


Assuntos
Displasia Ectodérmica , Fatores Reguladores de Interferon , Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Displasia Ectodérmica/metabolismo , Homeostase , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Queratinócitos/metabolismo , Nectinas , Proteínas Serina-Treonina Quinases
3.
Sensors (Basel) ; 23(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36679744

RESUMO

The demonstration of the first enzyme-based electrode to detect glucose, published in 1967 by S. J. Updike and G. P. Hicks, kicked off huge efforts in building sensors where biomolecules are exploited as native or modified to achieve new or improved sensing performances. In this growing area, bionanotechnology has become prominent in demonstrating how nanomaterials can be tailored into responsive nanostructures using biomolecules and integrated into sensors to detect different analytes, e.g., biomarkers, antibiotics, toxins and organic compounds as well as whole cells and microorganisms with very high sensitivity. Accounting for the natural affinity between biomolecules and almost every type of nanomaterials and taking advantage of well-known crosslinking strategies to stabilize the resulting hybrid nanostructures, biosensors with broad applications and with unprecedented low detection limits have been realized. This review depicts a comprehensive collection of the most recent biochemical and biophysical strategies for building hybrid devices based on bioconjugated nanomaterials and their applications in label-free detection for diagnostics, food and environmental analysis.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Nanoestruturas/química , Técnicas Biossensoriais/métodos , Biomarcadores
4.
Int J Mol Sci ; 24(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37240041

RESUMO

Affibodies and designed ankyrin repeat proteins (DARPins) are synthetic proteins originally derived from the Staphylococcus aureus virulence factor protein A and the human ankyrin repeat proteins, respectively. The use of these molecules in healthcare has been recently proposed as they are endowed with biochemical and biophysical features heavily demanded to target and fight diseases, as they have a strong binding affinity, solubility, small size, multiple functionalization sites, biocompatibility, and are easy to produce; furthermore, impressive chemical and thermal stability can be achieved. especially when using affibodies. In this sense, several examples reporting on affibodies and DARPins conjugated to nanomaterials have been published, demonstrating their suitability and feasibility in nanomedicine for cancer therapy. This minireview provides a survey of the most recent studies describing affibody- and DARPin-conjugated zero-dimensional nanomaterials, including inorganic, organic, and biological nanoparticles, nanorods, quantum dots, liposomes, and protein- and DNA-based assemblies for targeted cancer therapy in vitro and in vivo.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Proteínas de Repetição de Anquirina Projetadas , Proteínas/química , Neoplasias/tratamento farmacológico
5.
Mol Plant Microbe Interact ; 35(10): 881-886, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35704684

RESUMO

Oligogalacturonide (OG)-oxidase 1 (OGOX1) and cellodextrin (CD)-oxidase (CELLOX) are plant berberine bridge enzyme-like oligosaccharide oxidases that oxidize OGs and CDs, cell-wall fragments with the nature of damage-associated molecular patterns. The oxidation of OGs and CDs attenuates their elicitor activity and concomitantly releases H2O2. By using a multiple enzyme-based assay, we demonstrate that the H2O2 generated downstream of the combined action between a fungal polygalacturonase and OGOX1 or an endoglucanase and CELLOX can be directed by plant peroxidases (PODs) either towards a reaction possibly involved in plant defense, such as the oxidation of monolignol or a reaction possibly involved in a developmental event, such as the oxidation of auxin (indole-3-acetic acid), pointing to OGOX1 and CELLOX as enzymatic transducers between microbial glycoside hydrolases and plant PODs. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Celulase , Oxirredutases , Glicosídeo Hidrolases , Peróxido de Hidrogênio , Ácidos Indolacéticos , Oligossacarídeos , Oxirredutases N-Desmetilantes , Peroxidases , Plantas , Poligalacturonase , Transdutores
6.
Sensors (Basel) ; 22(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408102

RESUMO

In this study, nitrogen and sulfur co-doped carbon dots (NS-CDs) were investigated for the detection of heavy metals in water through absorption-based colorimetric response. NS-CDs were synthesized by a simple one-pot hydrothermal method and characterized by TEM, STEM-coupled with energy dispersive X-ray analysis, NMR, and IR spectroscopy. Addition of Cu(II) ions to NS-CD aqueous solutions gave origin to a distinct absorption band at 660 nm which was attributed to the formation of cuprammonium complexes through coordination with amino functional groups of NS-CDs. Absorbance increased linearly with Cu(II) concentration in the range 1-100 µM and enabled a limit of detection of 200 nM. No response was observed with the other tested metals, including Fe(III) which, however, appreciably decreased sensitivity to copper. Increase of pH of the NS-CD solution up to 9.5 greatly reduced this interference effect and enhanced the response to Cu(II), thus confirming the different nature of the two interactions. In addition, a concurrent response to Co(II) appeared in a different spectral region, thus suggesting the possibility of dual-species multiple sensitivity. The present method neither requires any other reagents nor any previous assay treatment and thus can be a promising candidate for low-cost monitoring of copper onsite and by unskilled personnel.


Assuntos
Carbono , Pontos Quânticos , Carbono/química , Cobalto , Colorimetria/métodos , Cobre/análise , Compostos Férricos , Nitrogênio/química , Pontos Quânticos/química , Enxofre , Água
7.
Int J Mol Sci ; 23(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36499257

RESUMO

There is evidence indicating that a vegan diet could be beneficial in the prevention of neurodegenerative disorders, including Alzheimer's disease (AD). The purpose of this review is to summarize the current knowledge on the positive and negative aspects of a vegan diet regarding the risk of AD. Regarding AD prevention, a vegan diet includes low levels of saturated fats and cholesterol, contributing to a healthy blood lipid profile. Furthermore, it is rich in phytonutrients, such as vitamins, antioxidants, and dietary fiber, that may help prevent cognitive decline. Moreover, a vegan diet contributes to the assumption of quercetin, a natural inhibitor of monoamine oxidase (MAO), which can contribute to maintaining mental health and reducing AD risk. Nonetheless, the data available do not allow an assessment of whether strict veganism is beneficial for AD prevention compared with vegetarianism or other diets. A vegan diet lacks specific vitamins and micronutrients and may result in nutritional deficiencies. Vegans not supplementing micronutrients are more prone to vitamin B12, vitamin D, and DHA deficiencies, which have been linked to AD. Thus, an evaluation of the net effect of a vegan diet on AD prevention and/or progression should be ascertained by taking into account all the positive and negative effects described here.


Assuntos
Doença de Alzheimer , Dieta Vegana , Humanos , Doença de Alzheimer/etiologia , Doença de Alzheimer/prevenção & controle , Veganos , Dieta Vegetariana , Micronutrientes , Vitaminas , Dieta
8.
Int J Mol Sci ; 23(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36293035

RESUMO

The K-homology (KH) domains are small, structurally conserved domains found in proteins of different origins characterized by a central conserved ßααß "core" and a GxxG motif in the loop between the two helices of the KH core. In the eukaryotic KHI type, additional αß elements decorate the "core" at the C-terminus. Proteins containing KH domains perform different functions and several diseases have been associated with mutations in these domains, including those in the fragile X mental retardation protein (FMRP). FMRP is an RNA-binding protein crucial for the control of RNA metabolism whose lack or mutations lead to fragile X syndrome (FXS). Among missense mutations, the R138Q substitution is in the KH0 degenerated domain lacking the classical GxxG motif. By combining equilibrium and kinetic experiments, we present a characterization of the folding mechanism of the KH0 domain from the FMRP wild-type and of the R138Q variant showing that in both cases the folding mechanism implies the accumulation of an on-pathway transient intermediate. Moreover, by exploiting a battery of biophysical techniques, we show that the KH0 domain has the propensity to form amyloid-like aggregates in mild conditions in vitro and that the R138Q mutation leads to a general destabilization of the protein and to an increased fibrillogenesis propensity.


Assuntos
Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil , Humanos , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/genética , Mutação de Sentido Incorreto , Proteínas/metabolismo , RNA/metabolismo
9.
Bioconjug Chem ; 32(1): 43-62, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33411522

RESUMO

Morpheeins are proteins that reversibly assemble into different oligomers, whose architectures are governed by conformational changes of the subunits. This property could be utilized in bionanotechnology where the building of nanometric and new high-ordered structures is required. By capitalizing on the adaptability of morpheeins to create patterned structures and exploiting their inborn affinity toward inorganic and living matter, "bottom-up" creation of nanostructures could be achieved using a single protein building block, which may be useful as such or as scaffolds for more complex materials. Peroxiredoxins represent the paradigm of a morpheein that can be applied to bionanotechnology. This review describes the structural and functional transitions that peroxiredoxins undergo to form high-order oligomers, e.g., rings, tubes, particles, and catenanes, and reports on the chemical and genetic engineering approaches to employ them in the generation of responsive nanostructures and nanodevices. The usefulness of the morpheeins' behavior is emphasized, supporting their use in future applications.


Assuntos
Nanoestruturas/química , Peroxirredoxinas/química , Proteínas/química , Biopolímeros/química , Peroxirredoxinas/metabolismo , Proteínas/metabolismo , Relação Estrutura-Atividade
10.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070389

RESUMO

Epilepsy as a chronic neurological disorder is characterized by recurrent, unprovoked epileptic seizures. In about half of the people who suffer from epilepsy, the root cause of the disorder is unknown. In the other cases, different factors can cause the onset of epilepsy. In recent years, the role of gut microbiota has been recognized in many neurological disorders, including epilepsy. These data are based on studies of the gut microbiota-brain axis, a relationship starting by a dysbiosis followed by an alteration of brain functions. Interestingly, epileptic patients may show signs of dysbiosis, therefore the normalization of the gut microbiota may lead to improvement of epilepsy and to greater efficacy of anticonvulsant drugs. In this descriptive review, we analyze the evidences for the role of gut microbiota in epilepsy and hypothesize a mechanism of action of these microorganisms in the pathogenesis and treatment of the disease. Human studies revealed an increased prevalence of Firmicutes in patients with refractory epilepsy. Exposure to various compounds can change microbiota composition, decreasing or exacerbating epileptic seizures. These include antibiotics, epileptic drugs, probiotics and ketogenic diet. Finally, we hypothesize that physical activity may play a role in epilepsy through the modulation of the gut microbiota.


Assuntos
Encéfalo/fisiopatologia , Disbiose , Epilepsia , Firmicutes , Microbioma Gastrointestinal , Epilepsia/metabolismo , Epilepsia/microbiologia , Epilepsia/fisiopatologia , Firmicutes/classificação , Firmicutes/metabolismo , Humanos
11.
Int J Mol Sci ; 22(12)2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199160

RESUMO

Acadesine (ACA), a pharmacological activator of AMP-activated protein kinase (AMPK), showed a promising beneficial effect in a mouse model of colitis, indicating this drug as an alternative tool to manage IBDs. However, ACA displays some pharmacodynamic limitations precluding its therapeutical applications. Our study was aimed at evaluating the in vitro and in vivo effects of FA-5 (a novel direct AMPK activator synthesized in our laboratories) in an experimental model of colitis in rats. A set of experiments evaluated the ability of FA5 to activate AMPK and to compare the efficacy of FA5 with ACA in an experimental model of colitis. The effects of FA-5, ACA, or dexamethasone were tested in rats with 2,4-dinitrobenzenesulfonic acid (DNBS)-induced colitis to assess systemic and tissue inflammatory parameters. In in vitro experiments, FA5 induced phosphorylation, and thus the activation, of AMPK, contextually to the activation of SIRT-1. In vivo, FA5 counteracted the increase in spleen weight, improved the colon length, ameliorated macroscopic damage score, and reduced TNF and MDA tissue levels in DNBS-treated rats. Of note, FA-5 displayed an increased anti-inflammatory efficacy as compared with ACA. The novel AMPK activator FA-5 displays an improved anti-inflammatory efficacy representing a promising pharmacological tool against bowel inflammation.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Benzofuranos/uso terapêutico , Desenvolvimento de Medicamentos , Ativadores de Enzimas/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Animais , Benzofuranos/farmacologia , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Colo/efeitos dos fármacos , Colo/patologia , Dinitrofluorbenzeno/análogos & derivados , Eletroforese em Gel Bidimensional , Ontologia Genética , Doenças Inflamatórias Intestinais/patologia , Interleucina-10/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley , Baço/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
12.
Hum Mutat ; 40(1): 106-114, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30371979

RESUMO

Hereditary sensory and autonomic neuropathies (HSAN) are clinically and genetically heterogeneous disorders, characterized by a progressive sensory neuropathy often complicated by ulcers and amputations, with variable motor and autonomic involvement. Several pathways have been implicated in the pathogenesis of neuronal degeneration in HSAN, while recent observations point to an emerging role of cytoskeleton organization and function. Here, we report novel biallelic mutations in the DST gene encoding dystonin, a large cytolinker protein of the plakin family, in an adult form of HSAN type VI. Affected individuals harbored the premature termination codon variant p.(Lys4330*) in trans with the p.(Ala203Glu) change affecting a highly conserved residue in an isoform-specific N-terminal region of dystonin. Functional studies showed defects in actin cytoskeleton organization and consequent delayed cell adhesion, spreading and migration, while recombinant p.Ala203Glu dystonin loses the ability to bind actin. Our data aid in the clinical and molecular delineation of HSAN-VI and suggest a central role for cell-motility and cytoskeletal defects in its pathogenesis possibly interfering with the neuronal outgrowth and guidance processes.


Assuntos
Citoesqueleto de Actina/patologia , Distonina/genética , Genes Recessivos , Neuropatias Hereditárias Sensoriais e Autônomas/genética , Mutação/genética , Neurônios/metabolismo , Actinas/metabolismo , Adulto , Idoso , Sequência de Aminoácidos , Animais , Células COS , Adesão Celular , Movimento Celular , Chlorocebus aethiops , Derme/patologia , Distonina/química , Família , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Isoformas de Proteínas/genética
13.
J Neuroinflammation ; 16(1): 108, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118068

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease whose various pathophysiological aspects are still being investigated. Recently, it has been hypothesized that AD may be associated with a dysbiosis of microbes in the intestine. In fact, the intestinal flora is able to influence the activity of the brain and cause its dysfunctions.Given the growing interest in this topic, the purpose of this review is to analyze the role of antibiotics in relation to the gut microbiota and AD. In the first part of the review, we briefly review the role of gut microbiota in the brain and the various theories supporting the hypothesis that dysbiosis can be associated with AD pathophysiology. In the second part, we analyze the possible role of antibiotics in these events. Antibiotics are normally used to remove or prevent bacterial colonization in the human body, without targeting specific types of bacteria. As a result, broad-spectrum antibiotics can greatly affect the composition of the gut microbiota, reduce its biodiversity, and delay colonization for a long period after administration. Thus, the action of antibiotics in AD could be wide and even opposite, depending on the type of antibiotic and on the specific role of the microbiome in AD pathogenesis.Alteration of the gut microbiota can induce changes in brain activity, which raise the possibility of therapeutic manipulation of the microbiome in AD and other neurological disorders. This field of research is currently undergoing great development, but therapeutic applications are still far away. Whether a therapeutic manipulation of gut microbiota in AD could be achieved using antibiotics is still not known. The future of antibiotics in AD depends on the research progresses in the role of gut bacteria. We must first understand how and when gut bacteria act to promote AD. Once the role of gut microbiota in AD is well established, one can think to induce modifications of the gut microbiota with the use of pre-, pro-, or antibiotics to produce therapeutic effects.


Assuntos
Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/microbiologia , Antibacterianos/efeitos adversos , Encéfalo/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Animais , Antibacterianos/administração & dosagem , Encéfalo/fisiologia , Disbiose/induzido quimicamente , Disbiose/microbiologia , Microbioma Gastrointestinal/fisiologia , Humanos , Probióticos/administração & dosagem , Probióticos/efeitos adversos
14.
Int J Mol Sci ; 20(10)2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31096580

RESUMO

Vascular cognitive impairment (VCI) is the second most common cause of cognitive deficit after Alzheimer's disease. Since VCI patients represent an important target population for prevention, an ongoing effort has been made to elucidate the pathogenesis of this disorder. In this review, we summarize the information from animal models on the molecular changes that occur in the brain during a cerebral vascular insult and ultimately lead to cognitive deficits in VCI. Animal models cannot effectively represent the complex clinical picture of VCI in humans. Nonetheless, they allow some understanding of the important molecular mechanisms leading to cognitive deficits. VCI may be caused by various mechanisms and metabolic pathways. The pathological mechanisms, in terms of cognitive deficits, may span from oxidative stress to vascular clearance of toxic waste products (such as amyloid beta) and from neuroinflammation to impaired function of microglia, astrocytes, pericytes, and endothelial cells. Impaired production of elements of the immune response, such as cytokines, and vascular factors, such as insulin-like growth factor 1 (IGF-1), may also affect cognitive functions. No single event could be seen as being the unique cause of cognitive deficits in VCI. These events are interconnected, and may produce cascade effects resulting in cognitive impairment.


Assuntos
Cognição , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Astrócitos/metabolismo , Encéfalo/metabolismo , Citocinas/metabolismo , Células Endoteliais/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Microglia/metabolismo , Modelos Animais , Óxido Nítrico , Estresse Oxidativo , Pericitos/metabolismo
15.
Acta Neuropsychiatr ; 31(2): 93-99, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30509331

RESUMO

OBJECTIVE: Genetic and environmental factors interact in the development of major depressive disorder (MDD). While neurobiological correlates have only partially been elucidated, altered levels of calcitonin gene-related peptide (CGRP)-like immunoreactivity (LI) in animal models and in the cerebrospinal fluid of depressed patients were reported, suggesting that CGRP may be involved in the pathophysiology and/or be a trait marker of MDD. However, changes in CGRP brain levels resulting from interactions between genetic and environmental risk factors and the response to antidepressant treatment have not been explored. METHODS: We therefore superimposed maternal separation (MS) onto a genetic rat model (Flinders-sensitive and -resistant lines, FSL/FRL) of depression, treated these rats with antidepressants (escitalopram and nortriptyline) and measured CGRP-LI in selected brain regions. RESULTS: CGRP was elevated in the frontal cortex, hippocampus and amygdala (but not in the hypothalamus) of FSL rats. However, MS did not significantly alter levels of this peptide. Likewise, there were no significant interactions between the genetic and environmental factors. Most importantly, neither escitalopram nor nortriptyline significantly altered brain CGRP levels. CONCLUSION: Our data demonstrate that increased brain levels of CGRP are present in a well-established rat model of depression. Given that antidepressants have virtually no effect on the brain level of this peptide, our study indicates that further research is needed to evaluate the functional role of CGRP in the FSL model for depression.


Assuntos
Antidepressivos/farmacologia , Encéfalo , Peptídeo Relacionado com Gene de Calcitonina , Citalopram/farmacologia , Depressão , Interação Gene-Ambiente , Privação Materna , Nortriptilina/farmacologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Depressão/tratamento farmacológico , Depressão/etiologia , Depressão/metabolismo , Modelos Animais de Doenças , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Ratos
16.
J Cell Physiol ; 233(5): 4091-4105, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28941284

RESUMO

Targeted anticancer therapies demand discovery of new cellular targets to be exploited for the delivery of toxic molecules and drugs. In this perspective, in the last few years, nucleolin has been identified as an interesting surface marker to be used for the therapy of glioblastoma. In this study, we investigated whether a synthetic antagonist of cell-surface nucleolin known as N6L, previously reported to decrease both tumor growth and tumor angiogenesis in several cancer cell lines, including glioblastoma cells, as well as endothelial cells proliferation, could be exploited to deliver a protein toxin (saporin) to glioblastoma cells. The pseudopeptide N6L cross-linked to saporin-S6 induced internalization of the toxin inside glioblastoma cancer cells. Our results in vitro demonstrated the effectiveness of this conjugate in inducing cell death, with an ID50 four orders of magnitude lower than that observed for free N6L. Furthermore, the preliminary in vivo study demonstrated efficiency in reducing the tumor mass in an orthotopic mouse model of glioblastoma.


Assuntos
Glioblastoma/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Peptídeos/farmacologia , Fosfoproteínas/farmacologia , Proteínas de Ligação a RNA/farmacologia , Animais , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Terapia de Alvo Molecular , Neovascularização Patológica/patologia , Peptídeos/química , Fosfoproteínas/química , Proteínas de Ligação a RNA/química , Saporinas/química , Saporinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Nucleolina
17.
Int J Neuropsychopharmacol ; 21(5): 485-498, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29471437

RESUMO

Background: Approach system considered a motivational system that activates reward-seeking behavior is associated with exploration/impulsivity, whereas avoidance system considered an attentional system that promotes inhibition of appetitive responses is associated with active overt withdrawal. Approach and avoidance dispositions are modulated by distinct neurochemical profiles and synaptic patterns. However, the precise working of neurons and trafficking of molecules in the brain activity predisposing to approach and avoidance are yet unclear. Methods: In 3 phenotypes of inbred mice, avoiding, balancing, and approaching mice, selected by using the Approach/Avoidance Y-maze, we analyzed endogenous brain levels of brain derived neurotrophic factor, one of the main secretory proteins with pleiotropic action. To verify the effects of the acute increase of brain derived neurotrophic factor, balancing and avoiding mice were bilaterally brain derived neurotrophic factor-infused in the cortical cerebellar regions. Results: Approaching animals showed high levels of explorative behavior and response to novelty and exhibited higher brain derived neurotrophic factor levels in the cerebellar structures in comparison to the other 2 phenotypes of mice. Interestingly, brain derived neurotrophic factor-infused balancing and avoiding mice significantly increased their explorative behavior and response to novelty. Conclusions: Cerebellar brain derived neurotrophic factor may play a role in explorative and novelty-seeking responses that sustain the approach predisposition.


Assuntos
Comportamento Animal/fisiologia , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Encéfalo/metabolismo , Comportamento Exploratório/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Comportamento Exploratório/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
18.
Biochim Biophys Acta ; 1850(9): 1891-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26033467

RESUMO

BACKGROUND: Leishmania infantum is a protozoan of the trypanosomatid family causing visceral leishmaniasis. Leishmania parasites are transmitted by the bite of phlebotomine sand flies to the human host and are phagocyted by macrophages. The parasites synthesize N1-N8-bis(glutationyl)-spermidine (trypanothione, TS2), which furnishes electrons to the tryparedoxin-tryparedoxin peroxidase couple to reduce the reactive oxygen species produced by macrophages. Trypanothione is kept reduced by trypanothione reductase (TR), a FAD-containing enzyme essential for parasite survival. METHODS: The enzymatic activity has been studied by stopped-flow, absorption spectroscopy, and amperometric measurements. RESULTS: The study reported here demonstrates that the steady-state parameters change as a function of the order of substrates addition to the TR-containing solution. In particular, when the reaction is carried out by adding NADPH to a solution containing the enzyme and trypanothione, the KM for NADPH decreases six times compared to the value obtained by adding TS2 as last reagent to start the reaction (1.9 vs. 12µM). More importantly, we demonstrate that TR is able to catalyze the oxidation of NADPH also in the absence of trypanothione. Thus, TR catalyzes the reduction of O2 to water through the sequential formation of C(4a)-(hydro)peroxyflavin and sulfenic acid intermediates. This NADPH:O2 oxidoreductase activity is shared by Saccharomyces cerevisiae glutathione reductase (GR). CONCLUSIONS: TR and GR, in the absence of their physiological substrates, may catalyze the electron transfer reaction from NADPH to molecular oxygen to yield water. GENERAL SIGNIFICANCE: TR and GR are promiscuous enzymes.


Assuntos
Glutationa Redutase/metabolismo , Leishmania infantum/enzimologia , NADH NADPH Oxirredutases/metabolismo , Oxigênio/metabolismo , Catálise , Transporte de Elétrons , NADP/metabolismo , Oxirredução , Consumo de Oxigênio
19.
Microb Cell Fact ; 15(1): 194, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27842546

RESUMO

BACKGROUND: The big challenge in any anti-tumor therapeutic approach is represented by the development of drugs selectively acting on the target with limited side effects, that exploit the unique characteristics of malignant cells. The urokinase (urokinase-type plasminogen activator, uPA) and its receptor uPAR have been identified as preferential target candidates since they play a key role in the evolution of neoplasms and are associated with neoplasm aggressiveness and poor clinical outcome in several different tumor types. RESULTS: To selectively target uPAR over-expressing cancer cells, we prepared a set of chimeric proteins (ATF-SAP) formed by the human amino terminal fragments (ATF) of uPA and the plant ribosome inactivating protein saporin (SAP). Codon-usage optimization was used to increase the expression levels of the chimera in the methylotrophic yeast Pichia pastoris. We then moved the bioprocess to bioreactors and demonstrated that the fed-batch production of the recombinant protein can be successfully achieved, obtaining homogeneous discrete batches of the desired constructs. We also determined the cytotoxic activity of the obtained batch of ATF-SAP which was specifically cytotoxic for U937 leukemia cells, while another construct containing a catalytically inactive mutant form of SAP showed no activity. CONCLUSION: Our results demonstrate that the uPAR-targeted, saporin-based recombinant fusion ATF-SAP can be produced in a fed-batch fermentation with full retention of the molecules selective cytotoxicity and hence therapeutic potential.


Assuntos
Proteínas Recombinantes de Fusão/biossíntese , Proteínas Inativadoras de Ribossomos Tipo 1/biossíntese , Ativador de Plasminogênio Tipo Uroquinase/biossíntese , Reatores Biológicos , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Humanos , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Inativadoras de Ribossomos Tipo 1/genética , Proteínas Inativadoras de Ribossomos Tipo 1/farmacologia , Saporinas , Células U937 , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/farmacologia
20.
Can J Physiol Pharmacol ; 94(4): 455-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26863448

RESUMO

Increasing evidence suggests that motor rehabilitation may delay Parkinson's disease (PD) progression. Moreover, parallel treatments in animals up-regulate brain-derived neurotrophic factor (BDNF). Thus, we investigated the effect of a motor rehabilitation protocol on PD symptoms and BDNF serum levels. Motor rehabilitation training consisted of a cycle of 20 days/month of physiotherapy divided in 3 daily sessions. Clinical data were collected at the beginning, at the end, and at 90 days follow-up. BDNF serum levels were detected by ELISA at 0, 7, 14, 21, 30, and 90 days. The follow-up period had a duration of 60 days (T30-T90). The results showed that at the end of the treatment (day 30), an improvement in extrapyramidal signs (UPDRS III; UPDRS III - Gait and Balance items), motor (6 Minute Walking Test), and daily living activities (UPDRS II; PDQ-39) was observed. BDNF levels were increased at day 7 as compared with baseline. After that, no changes in BDNF were observed during the treatment and in the successive follow-up. This study demonstrates that motor rehabilitation training is able to ameliorate PD symptoms and to increase temporarily BDNF serum levels. The latter effect may potentially contribute to the therapeutic action.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Atividade Motora/fisiologia , Doença de Parkinson/sangue , Doença de Parkinson/fisiopatologia , Atividades Cotidianas , Idoso , Feminino , Marcha/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Ensino , Regulação para Cima/fisiologia
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