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1.
Hum Mol Genet ; 26(24): 4823-4835, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29036636

RESUMO

Aging is the major risk factor for several neurodegenerative diseases, including Alzheimer's disease (AD). However, the mechanisms by which aging contributes to neurodegeneration remain elusive. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a transcription factor that regulates expression of a vast number of genes by binding to the antioxidant response element. Nrf2 levels decrease as a function of age, and reduced Nrf2 levels have been reported in postmortem human brains and animal models of AD. Nevertheless, it is still unknown whether Nrf2 plays a role in the cognitive deficits associated with AD. To address this question, we used a genetic approach to remove the Nrf2 gene from APP/PS1 mice, a widely used animal model of AD. We found that the lack of Nrf2 significantly exacerbates cognitive deficits in APP/PS1, without altering gross motor function. Specifically, we found an exacerbation of deficits in spatial learning and memory, as well as in working and associative memory. Different brain regions control these behavioral tests, indicating that the lack of Nrf2 has a global effect on brain function. The changes in cognition were linked to an increase in Aß and interferon-gamma (IFNγ) levels, and microgliosis. The changes in IFNγ levels are noteworthy as previously published evidence indicates that IFNγ can increase microglia activation and induce Aß production. Our data suggest a clear link between Nrf2 and AD-mediated cognitive decline and further strengthen the connection between Nrf2 and AD.


Assuntos
Doença de Alzheimer/genética , Transtornos Cognitivos/genética , Fator 2 Relacionado a NF-E2/deficiência , Fator 2 Relacionado a NF-E2/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Transtornos Cognitivos/metabolismo , Modelos Animais de Doenças , Feminino , Masculino , Transtornos da Memória/genética , Camundongos , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2/metabolismo , Presenilina-1/genética
2.
Int J Mol Sci ; 18(1)2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-28106772

RESUMO

CSP-1103 (formerly CHF5074) has been shown to reverse memory impairment and reduce amyloid plaque as well as inflammatory microglia activation in preclinical models of Alzheimer's disease. Moreover, it was found to improve cognition and reduce brain inflammation in patients with mild cognitive impairment. Recent evidence suggests that CSP-1103 acts through a single molecular target, the amyloid precursor protein intracellular domain (AICD), a transcriptional regulator implicated in inflammation and apoptosis. We here tested the possible anti-apoptotic and neuroprotective activity of CSP-1103 in a cell-based model of post-ischemic injury, wherein the primary mouse cortical neurons were exposed to oxygen-glucose deprivation (OGD). When added after OGD, CSP-1103 prevented the apoptosis cascade by reducing cytochrome c release and caspase-3 activation and the secondary necrosis. Additionally, CSP-1103 limited earlier activation of p38 and nuclear factor κB (NF-κB) pathways. These results demonstrate that CSP-1103 is neuroprotective in a model of post-ischemic brain injury and provide further mechanistic insights as regards its ability to reduce apoptosis and potential production of pro-inflammatory cytokines. In conclusion, these findings suggest a potential use of CSP-1103 for the treatment of brain ischemia.


Assuntos
Apoptose/efeitos dos fármacos , Ciclopropanos/farmacologia , Flurbiprofeno/análogos & derivados , Glucose/deficiência , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Oxigênio/farmacologia , Animais , Caspase 3/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Córtex Cerebral/patologia , Citocromos c/metabolismo , Ativação Enzimática/efeitos dos fármacos , Flurbiprofeno/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Ibuprofeno/farmacologia , Camundongos Endogâmicos C57BL , Necrose , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fator de Transcrição RelA/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
J Neurosci ; 35(41): 14042-56, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26468204

RESUMO

Aging is the most important risk factor associated with Alzheimer's disease (AD); however, the molecular mechanisms linking aging to AD remain unclear. Suppression of the ribosomal protein S6 kinase 1 (S6K1) increases healthspan and lifespan in several organisms, from nematodes to mammals. Here we show that S6K1 expression is upregulated in the brains of AD patients. Using a mouse model of AD, we found that genetic reduction of S6K1 improved synaptic plasticity and spatial memory deficits, and reduced the accumulation of amyloid-ß and tau, the two neuropathological hallmarks of AD. Mechanistically, these changes were linked to reduced translation of tau and the ß-site amyloid precursor protein cleaving enzyme 1, a key enzyme in the generation of amyloid-ß. Our results implicate S6K1 dysregulation as a previously unidentified molecular mechanism underlying synaptic and memory deficits in AD. These findings further suggest that therapeutic manipulation of S6K1 could be a valid approach to mitigate AD pathology. SIGNIFICANCE STATEMENT: Aging is the most important risk factor for Alzheimer's disease (AD). However, little is known about how it contributes to AD pathogenesis. S6 kinase 1 (S6K1) is a protein kinase involved in regulation of protein translation. Reducing S6K1 activity increases lifespan and healthspan. We report the novel finding that reducing S6K1 activity in 3xTg-AD mice ameliorates synaptic and cognitive deficits. These improvement were associated with a reduction in amyloid-ß and tau pathology. Mechanistically, lowering S6K1 levels reduced translation of ß-site amyloid precursor protein cleaving enzyme 1 and tau, two key proteins involved in AD pathogenesis. These data suggest that S6K1 may represent a molecular link between aging and AD. Given that aging is the most important risk factor for most neurodegenerative diseases, our results may have far-reaching implications into other diseases.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Regulação da Expressão Gênica/fisiologia , Transtornos da Memória/terapia , Plasticidade Neuronal/fisiologia , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Hipocampo/patologia , Humanos , Locomoção/genética , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/genética , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/etiologia , Camundongos , Camundongos Transgênicos , Plasticidade Neuronal/genética , Neurônios/fisiologia , Fragmentos de Peptídeos/metabolismo , Presenilina-1/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Transdução de Sinais/genética , Proteínas tau/genética , Proteínas tau/metabolismo
4.
J Neurosci ; 34(23): 7988-98, 2014 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-24899720

RESUMO

Elevated mammalian target of rapamycin (mTOR) signaling has been found in Alzheimer's disease (AD) patients and is linked to diabetes and aging, two known risk factors for AD. However, whether hyperactive mTOR plays a role in the cognitive deficits associated with AD remains elusive. Here, we genetically reduced mTOR signaling in the brains of Tg2576 mice, a widely used animal model of AD. We found that suppression of mTOR signaling reduced amyloid-ß deposits and rescued memory deficits. Mechanistically, the reduction in mTOR signaling led to an increase in autophagy induction and restored the hippocampal gene expression signature of the Tg2576 mice to wild-type levels. Our results implicate hyperactive mTOR signaling as a previous unidentified signaling pathway underlying gene-expression dysregulation and cognitive deficits in AD. Furthermore, hyperactive mTOR signaling may represent a molecular pathway by which aging contributes to the development of AD.


Assuntos
Doença de Alzheimer/complicações , Transtornos Cognitivos , Regulação da Expressão Gênica/genética , Expressão Gênica/genética , Hipocampo/fisiopatologia , Serina-Treonina Quinases TOR/metabolismo , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Transtornos Cognitivos/terapia , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Hipocampo/efeitos dos fármacos , Humanos , Imunossupressores/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/genética
5.
Neurosci Biobehav Rev ; 160: 105637, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38519023

RESUMO

Tics are sudden, repetitive movements or vocalizations. Tic disorders, such as Tourette syndrome (TS), are contributed by the interplay of genetic risk factors and environmental variables, leading to abnormalities in the functioning of the cortico-striatal-thalamo-cortical (CSTC) circuitry. Various neurotransmitter systems, such as gamma-aminobutyric acid (GABA) and dopamine, are implicated in the pathophysiology of these disorders. Building on the evidence that tic disorders are predominant in males and exacerbated by stress, emerging research is focusing on the involvement of neuroactive steroids, including dehydroepiandrosterone sulfate (DHEAS) and allopregnanolone, in the ontogeny of tics and other phenotypes associated with TS. Emerging evidence indicates that DHEAS levels are significantly elevated in the plasma of TS-affected boys, and the clinical onset of this disorder coincides with the period of adrenarche, the developmental stage characterized by a surge in DHEAS synthesis. On the other hand, allopregnanolone has garnered particular attention for its potential to mediate the adverse effects of acute stress on the exacerbation of tic severity and frequency. Notably, both neurosteroids act as key modulators of GABA-A receptors, suggesting a pivotal role of these targets in the pathophysiology of various clinical manifestations of tic disorders. This review explores the potential mechanisms by which these and other neuroactive steroids may influence tic disorders and discusses the emerging therapeutic strategies that target neuroactive steroids for the management of tic disorders.


Assuntos
Neuroesteroides , Transtornos de Tique , Tiques , Síndrome de Tourette , Masculino , Humanos , Pregnanolona/farmacologia
6.
Br J Pharmacol ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689378

RESUMO

BACKGROUND AND PURPOSE: Current pharmacotherapies for Tourette syndrome (TS) are often unsatisfactory and poorly tolerated, underscoring the need for novel treatments. Insufficient striatal acetylcholine has been suggested to contribute to tic ontogeny. Thus, we tested whether activating M1 and/or M4 receptors-the two most abundant muscarinic receptors in the striatum-reduced tic-related behaviours in mouse models of TS. EXPERIMENTAL APPROACH: Studies were conducted using CIN-d and D1CT-7 mice, two TS models characterized by early-life depletion of striatal cholinergic interneurons and cortical neuropotentiation, respectively. First, we tested the effects of systemic and intrastriatal xanomeline, a selective M1/M4 receptor agonist, on tic-like and other TS-related responses. Then, we examined whether xanomeline effects were reduced by either M1 or M4 antagonists or mimicked by the M1/M3 agonist cevimeline or the M4 positive allosteric modulator (PAM) VU0467154. Finally, we measured striatal levels of M1 and M4 receptors and assessed the impact of VU0461754 on the striatal expression of the neural marker activity c-Fos. KEY RESULTS: Systemic and intrastriatal xanomeline reduced TS-related behaviours in CIN-d and D1CT-7 mice. Most effects were blocked by M4, but not M1, receptor antagonists. VU0467154, but not cevimeline, elicited xanomeline-like ameliorative effects in both models. M4, but not M1, receptors were down-regulated in the striatum of CIN-d mice. Additionally, VU0467154 reduced striatal c-Fos levels in these animals. CONCLUSION AND IMPLICATIONS: Activation of striatal M4, but not M1, receptors reduced tic-like manifestations in mouse models, pointing to xanomeline and M4 PAMs as novel putative therapeutic strategies for TS.

7.
Neurobiol Dis ; 49: 177-89, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22971966

RESUMO

UNLABELLED: Nuclear factor-kappaB (NF-κB) p50/RelA is a key molecule with a dual effect in the progression of ischemic stroke. In harmful ischemia, but not in preconditioning insult, neurotoxic activation of p50/RelA is characterized by RelA-specific acetylation at Lys310 (K310) and deacetylation at other Lys residues. The derangement of RelA acetylation is associated with activation of Bim promoter. OBJECTIVE: With the aim of producing neuroprotection by correcting altered acetylation of RelA in brain ischemia, we combined the pharmacological inhibition of histone deacetylase (HDAC) 1-3, the enzymes known to reduce global RelA acetylation, and the activation of sirtuin 1, endowed with a specific deacetylase activity on the K310 residue of RelA. To afford this aim, we tested the clinically used HDAC 1-3 inhibitor entinostat (MS-275) and the sirtuin 1 activator resveratrol. METHODS: We used the mouse model of transient middle cerebral artery occlusion (MCAO) and primary cortical neurons exposed to oxygen glucose deprivation (OGD). RESULTS: The combined use of MS-275 and resveratrol, by restoring normal RelA acetylation, elicited a synergistic neuroprotection in neurons exposed to OGD. This effect correlated with MS-275 capability to increase total RelA acetylation and resveratrol capability to reduce RelA K310 acetylation through the activation of an AMP-activated protein kinase-sirtuin 1 pathway. The synergistic treatment reproduced the acetylation state of RelA peculiar of preconditioning ischemia. Neurons exposed to the combined drugs totally recovered the optimal histone H3 acetylation. Neuroprotection was reproduced in mice subjected to MCAO and treated with MS-275 (20µg/kg and 200µg/kg) or resveratrol (6800µg/kg) individually. However, the administration of lowest doses of MS-275 (2µg/kg) and resveratrol (68µg/kg) synergistically reduced infarct volume and neurological deficits. Importantly, the treatment was effective even when administered 7h after the stroke onset. Chromatin immunoprecipitation analysis of cortices harvested from treated mice showed that the RelA binding and histone acetylation increased at the Bcl-xL promoter and decreased at the Bim promoter. CONCLUSION: Our study reveals that epigenetic therapy shaping acetylation of both RelA and histones may be a promising strategy to limit post-ischemic injury with an extended therapeutic window.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Epigênese Genética/efeitos dos fármacos , Histonas/metabolismo , NF-kappa B/metabolismo , Fármacos Neuroprotetores/farmacologia , Fator de Transcrição RelA/metabolismo , Acetilação/efeitos dos fármacos , Animais , Benzamidas/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Modelos Animais de Doenças , Epigênese Genética/fisiologia , Glucose/deficiência , Inibidores de Histona Desacetilases/farmacologia , Infarto da Artéria Cerebral Média , Masculino , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neurônios/patologia , Piridinas/farmacologia , Resveratrol , Sirtuína 1/metabolismo , Estilbenos/farmacologia
8.
Proc Natl Acad Sci U S A ; 107(52): 22457-62, 2010 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-21148100

RESUMO

It is becoming common practice to partition glass-forming liquids into two classes based on the dependence of the shear viscosity η on temperature T. In an Arrhenius plot, ln η vs 1/T, a strong liquid shows linear behavior whereas a fragile liquid exhibits an upward curvature [super-Arrhenius (SA) behavior], a situation customarily described by using the Vogel-Fulcher-Tammann law. Here we analyze existing data of the transport coefficients of 84 glass-forming liquids. We show the data are consistent, on decreasing temperature, with the onset of a well-defined dynamical crossover η(×), where η(×) has the same value, η(×) ≈ 10(3) Poise, for all 84 liquids. The crossover temperature, T(×), located well above the calorimetric glass transition temperature T(g), marks significant variations in the system thermodynamics, evidenced by the change of the SA-like T dependence above T(×) to Arrhenius behavior below T(×). We also show that below T(×) the familiar Stokes-Einstein relation D/T ∼ η(-1) breaks down and is replaced by a fractional form D/T ∼ η(-ζ), with ζ ≈ 0.85.


Assuntos
Vidro/química , Solventes/química , Termodinâmica , Temperatura de Transição , Algoritmos , Calorimetria , Transição de Fase , Viscosidade
9.
Nanomaterials (Basel) ; 13(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38063735

RESUMO

Solid-state supercapacitors with areal capacitance in the order of 100 mF⋅cm-2 are developed on paper substrates, using eco-friendly, low-cost materials and a simple technology. The electrochemically active material used as the electrode is prepared from a stable water-based ink, obtained by doping commercial polypyrrole (PPY) powder with dodecylbenzene sulfonic acid (DBSA), and characterized by optical and electrical measurements, Raman investigation and Atomic Force Microscopy. The PPY:DBSA ink can be directly applied on paper by means of rechargeable water pens, obtaining, after drying, electrically conducting solid state tracks. The PPY:DBSA layers are then interfaced to one another through a polymer gel based on potassium hydroxide and chitosan, acting both as the ion-conducting medium and as the separator. The areal capacitance of the devices developed by following such a simple rule can be improved when the PPY:DBSA ink is applied in combination with other nanostructured carbon material.

10.
Sci Total Environ ; 904: 167244, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37758135

RESUMO

Monitoring the occurrence of microplastic contamination in the Antarctic area is the key to implement policy measures for waste regulations in the research stations. Antarctic fish Trematomus bernachii is a suitable species for establishing microplastic contamination and for investigating changes over time in the concentration and type of microplastics in the Antarctic region. In this paper a total of 78 fish, caught during the 37th Italian Antarctic expedition (2021-2022) in the Ross Sea (Antarctica) were analysed. Different microfibers and dyes were identified by Raman spectroscopy and the results were compared with those obtained for fish sampled in 1998. Differences in polymer type emerged with a predominance of synthetic fibers with respect to natural ones. These changes appear to be related to the increased human activities in the Antarctica over the last twenty years and highlights the need to improve the environmental sustainability of the numerous research stations operating throughout that area.


Assuntos
Perciformes , Poluentes Químicos da Água , Animais , Humanos , Microplásticos , Plásticos/análise , Regiões Antárticas , Baías , Peixes , Monitoramento Ambiental/métodos , Aves , Poluentes Químicos da Água/análise
11.
iScience ; 26(10): 107879, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37868627

RESUMO

Renal ischemia-reperfusion injury (IRI) is associated with reduced allograft survival, and each additional hour of cold ischemia time increases the risk of graft failure and mortality following renal transplantation. Receptor-interacting protein kinase 3 (RIPK3) is a key effector of necroptosis, a regulated form of cell death. Here, we evaluate the first-in-human RIPK3 expression dataset following IRI in kidney transplantation. The primary analysis included 374 baseline biopsy samples obtained from renal allografts 10 minutes after onset of reperfusion. RIPK3 was primarily detected in proximal tubular cells and distal tubular cells, both of which are affected by IRI. Time-to-event analysis revealed that high RIPK3 expression is associated with a significantly higher risk of one-year transplant failure and prognostic for one-year (death-censored) transplant failure independent of donor and recipient associated risk factors in multivariable analyses. The RIPK3 score also correlated with deceased donation, cold ischemia time and the extent of tubular injury.

12.
J Funct Biomater ; 13(2)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35466221

RESUMO

Achieving homogenous dispersion of nanoparticles inside a polymeric matrix is a great challenge for numerous applications. In the present study, we aim at understanding the role of different factors on the dispersion properties of TiO2 in pluronic F-127 mixtures. The mixtures were prepared with different pH and guest/host ratios and investigated by UV-Vis spectroscopy, dynamic light scattering, infrared spectroscopy and electrical conductivity. Depending on the preparation conditions, different amounts of TiO2 were loaded within the copolymer as quantitatively determined by UV-Vis spectroscopy. The different content of nanoparticles has direct implications on the gelation and micellization of pluronic analyzed by dynamic light scattering. The information derived on the self-assembly behavior was interpreted in relation to the infrared and conductivity measurements results. Together, these results shed light on the most favorable conditions for improving the nanoparticle dispersion inside the copolymer matrix and suggest a possible strategy to design functional nanoparticle-polymer systems.

13.
Sci Rep ; 12(1): 17214, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36241682

RESUMO

Anthropogenic microparticles (AMs) were found for the first time in specimens of Trematomus bernacchii collected in 1998 in the Ross Sea (Antarctica) and stored in the Antarctic Environmental Specimen Bank. Most of the identified AMs were fibers of natural and synthetic origin. The natural AMs were cellulosic, the synthetic ones were polyester, polypropylene, polypropylene/polyester, and cellulose acetate. The presence of dyes in the natural AMs indicates their anthropogenic origin. Five industrial dyes were identified by Raman spectroscopy with Indigo occurring in most of them (55%). Our research not only adds further data to the ongoing knowledge of pollution levels in the Antarctic ecosystem, it provides an interesting snapshot of the past, highlighting that microplastics and anthropogenic fiber pollution had already entered the Antarctic marine food web at the end of the '90 s. These findings therefore establish the foundations for understand the changes in marine litter pollution over time.


Assuntos
Ecossistema , Perciformes , Animais , Regiões Antárticas , Aves , Corantes , Índigo Carmim , Microplásticos , Plásticos , Poliésteres , Polipropilenos
14.
Oncogene ; 41(9): 1376-1382, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35091677

RESUMO

A variety of cancer entities are driven by KRAS mutations, which remain difficult to target clinically. Survival pathways, such as resistance to cell death, may represent a promising treatment approach in KRAS mutated cancers. Based on the frequently observed genomic deletions of BCL-2-related ovarian killer (BOK) in cancer patients, we explored the function of BOK in a mutant KrasG12D-driven murine model of lung cancer. Using KrasG12D/+ Bok-/- mice, we observed an overall tumor-promoting function of BOK in vivo. Specifically, loss of BOK reduced proliferation both in cell lines in vitro as well as in KrasG12D-driven tumor lesions in vivo. During tumor development in vivo, loss of BOK resulted in a lower tumor burden, with fewer, smaller, and less advanced tumors. Using KrasG12D/+ Tp53Δ/Δ Bok-/- mice, we identified that this phenotype was entirely dependent on the presence of functional p53. Furthermore, analysis of a human dataset of untreated early-stage lung tumors did not identify any common deletion of the BOK locus, independently of the TP53 status or the histopathological classification. Taken together our data indicate that BOK supports tumor progression in Kras-driven lung cancer.


Assuntos
Proteína Supressora de Tumor p53
15.
J Cancer Res Clin Oncol ; 148(2): 331-340, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34654952

RESUMO

PURPOSE: Hypereosinophilia represents a heterogenous group of severe medical conditions characterized by elevated numbers of eosinophil granulocytes in peripheral blood, bone marrow or tissue. Treatment options for hypereosinophilia remain limited despite recent approaches including IL-5-targeted monoclonal antibodies and tyrosine kinase inhibitors. METHODS: To understand aberrant survival patterns and options for pharmacologic intervention, we characterized BCL-2-regulated apoptosis signaling by testing for BCL-2 family expression levels as well as pharmacologic inhibition using primary patient samples from diverse subtypes of hypereosinophilia (hypereosinophilic syndrome n = 18, chronic eosinophilic leukemia not otherwise specified n = 9, lymphocyte-variant hypereosinophilia n = 2, myeloproliferative neoplasm with eosinophilia n = 2, eosinophilic granulomatosis with polyangiitis n = 11, reactive eosinophilia n = 3). RESULTS: Contrary to published literature, we found no difference in the levels of the lncRNA Morrbid and its target BIM. Yet, we identified a near complete loss of expression of pro-apoptotic PUMA as well as a reduction in anti-apoptotic BCL-2. Accordingly, BCL-2 inhibition using venetoclax failed to achieve cell death induction in eosinophil granulocytes and bone marrow mononuclear cells from patients with hypereosinophilia. In contrast, MCL1 inhibition using S63845 specifically decreased the viability of bone marrow progenitor cells in patients with hypereosinophilia. In patients diagnosed with Chronic Eosinophilic Leukemia (CEL-NOS) or Myeloid and Lymphatic Neoplasia with hypereosinophilia (MLN-Eo) repression of survival was specifically powerful. CONCLUSION: Our study shows that MCL1 inhibition might be a promising therapeutic option for hypereosinophilia patients specifically for CEL-NOS and MLN-Eo.


Assuntos
Eosinófilos/metabolismo , Síndrome Hipereosinofílica/genética , Síndrome Hipereosinofílica/terapia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Proteína 11 Semelhante a Bcl-2/fisiologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Estudos de Casos e Controles , Células Cultivadas , Eosinofilia/genética , Eosinofilia/mortalidade , Eosinofilia/patologia , Eosinofilia/terapia , Eosinófilos/patologia , Granulomatose com Poliangiite/genética , Granulomatose com Poliangiite/patologia , Granulomatose com Poliangiite/terapia , Células HL-60 , Humanos , Síndrome Hipereosinofílica/mortalidade , Síndrome Hipereosinofílica/patologia , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Transtornos Mieloproliferativos/terapia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirimidinas/uso terapêutico , Sulfonamidas/uso terapêutico , Tiofenos/uso terapêutico
16.
Nanomaterials (Basel) ; 11(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34685029

RESUMO

Flexible energy storage devices and supercapacitors in particular have become very attractive due to the growing demand for wearable consumer devices. To obtain supercapacitors with improved performance, it is useful to resort to hybrid electrodes, usually nanocomposites, that combine the excellent charge transport properties and high surface area of nanostructured carbon with the electrochemical activity of suitable metal oxides or conjugated polymers. In this work, electrochemically active conducting inks are developed starting from commercially available polypyrrole and graphene nanoplatelets blended with dodecylbenzenesulfonic acid. Films prepared by applying the developed inks are characterized by means of Raman measurements, Fourier Transform Infrared (FTIR) analysis, and Atomic Force Microscopy (AFM) investigations. Planar supercapacitor prototypes with an active area below ten mm2 are then prepared by applying the inks onto transparency sheets, separated by an ion-permeable nafion layer impregnated with lithium hexafluorophospate, and characterized by means of electrical measurements. According to the experimental results, the devices show both pseudocapacitive and electric double layer behavior, resulting in areal capacitance that, when obtained from about 100 mF⋅cm-2 in the sample with polypyrrole-based electrodes, increases by a factor of about 3 when using electrodes deposited from inks containing polypyrrole and graphene nanoplateles.

17.
Nanomaterials (Basel) ; 11(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34835661

RESUMO

The concentration of sodium and potassium ions in biological fluids, such as blood, urine and sweat, is indicative of several basic body function conditions. Therefore, the development of simple methods able to detect these alkaline ions is of outmost importance. In this study, we explored the electrochemical and optical properties of graphene quantum dots (GQDs) combined with the selective chelating ability of the crown ethers 15-crown-5 and 18-crown-6, with the final aim to propose novel composites for the effective detection of these ions. The results obtained comparing the performances of the single GQDs and crown ethers with those of the GQDs-15-crown-5 and GQDs-18-crown-6 composites, have demonstrated the superior properties of these latter. Electrochemical investigation showed that the GQDs based composites can be exploited for the potentiometric detection of Na+ and K+ ions, but selectivity still remains a concern. The nanocomposites showed the characteristic fluorescence emissions of GQDs and crown ethers. The GQDs-18-crown-6 composite exhibited ratiometric fluorescence emission behavior with the variation of K+ concentration, demonstrating its promising properties for the development of a selective fluorescent method for potassium determination.

18.
Sci Immunol ; 6(65): eabf7235, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34739338

RESUMO

Deficiency in X-linked inhibitor of apoptosis protein (XIAP) is the cause for X-linked lymphoproliferative syndrome 2 (XLP2). About one-third of these patients suffer from severe and therapy-refractory inflammatory bowel disease (IBD), but the exact cause of this pathogenesis remains undefined. Here, we used XIAP-deficient mice to characterize the mechanisms underlying intestinal inflammation. In Xiap−/− mice, we observed spontaneous terminal ileitis and microbial dysbiosis characterized by a reduction of Clostridia species. We showed that in inflamed mice, both TNF receptor 1 and 2 (TNFR1/2) cooperated in promoting ileitis by targeting TLR5-expressing Paneth cells (PCs) or dendritic cells (DCs). Using intestinal organoids and in vivo modeling, we demonstrated that TLR5 signaling triggered TNF production, which induced PC dysfunction mediated by TNFR1. TNFR2 acted upon lamina propria immune cells. scRNA-seq identified a DC population expressing TLR5, in which Tnfr2 expression was also elevated. Thus, the combined activity of TLR5 and TNFR2 signaling may be responsible for DC loss in lamina propria of Xiap−/− mice. Consequently, both Tnfr1−/−Xiap−/− and Tnfr2−/−Xiap−/− mice were rescued from dysbiosis and intestinal inflammation. Furthermore, RNA-seq of ileal crypts revealed that in inflamed Xiap−/− mice, TLR5 signaling was abrogated, linking aberrant TNF responses with the development of a dysbiosis. Evidence for TNFR2 signaling driving intestinal inflammation was detected in XLP2 patient samples. Together, these data point toward a key role of XIAP in mediating resilience of TLR5-expressing PCs and intestinal DCs, allowing them to maintain tissue integrity and microbiota homeostasis.


Assuntos
Inflamação/imunologia , Intestinos/imunologia , Receptores Tipo II do Fator de Necrose Tumoral/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Receptor 5 Toll-Like/imunologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/imunologia , Animais , Células Dendríticas/imunologia , Disbiose/imunologia , Humanos , Imunidade Inata/imunologia , Camundongos , Camundongos Knockout , Celulas de Paneth/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/deficiência , Receptores Tipo II do Fator de Necrose Tumoral/deficiência , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/deficiência
19.
Proc Natl Acad Sci U S A ; 104(47): 18387-91, 2007 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-18000049

RESUMO

The temperature dependence of the density of water, rho(T), is obtained by means of optical scattering data, Raman and Fourier transform infrared, in a very wide temperature range, 30 < T < 373 K. This interval covers three regions: the thermodynamically stable liquid phase, the metastable supercooled phase, and the low-density amorphous solid phase, at very low T. From analyses of the profile of the OH stretching spectra, we determine the fractional weight of the two main spectral components characterized by two different local hydrogen bond structures. They are, as predicted by the liquid-liquid phase transition hypothesis of liquid water, the low- and the high-density liquid phases. We evaluate contributions to the density of these two phases and thus are able to calculate the absolute density of water as a function of T. We observe in rho(T) a complex thermal behavior characterized not only by the well known maximum in the stable liquid phase at T = 277 K, but also by a well defined minimum in the deeply supercooled region at 203 +/- 5 K, in agreement with suggestions from molecular dynamics simulations.

20.
Mar Pollut Bull ; 150: 110596, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733904

RESUMO

This study highlights plastics occurrence in five demersal fish species from the Southern Tyrrhenian Sea: the Red mullet Mullus barbatus barbatus, the Piper gurnard Trigla lyra, the Blackmouth catshark Galeus melastomus, the Lesser spotted dogfish Scyliorhinus canicula and the Brown ray Raja miraletus. Overall, 125 fish were examined: 21 Red mullets, 16 Piper gurnards, 75 Blackmouth catsharks, 72 Dogfish and 1 Brown ray. The percentage of fish with ingested plastics was 14.4% with 0.24 items per specimen. The majority of the debris were fibers and the application of infrared and Raman spectroscopy allowed the identification and discrimination of plastic and non-plastic fibers. The plastic debris isolated were mainly microplastics (94.1%), while macroplastics occurrence was very low (5.9%). The plastics were identified as polypropylene, Teflon, nylon, kraton G (triblock copolymer) and polyethylene. Also cellulose was detected. S. canicula was the species with the highest number of plastic pollutants.


Assuntos
Monitoramento Ambiental , Perciformes , Plásticos , Poluentes Químicos da Água , Animais , Peixes , Mar Mediterrâneo
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