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1.
Clin Rehabil ; 38(6): 783-792, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38291625

RESUMO

OBJECTIVE: To determine whether implementing a Facebook training program improves the effectiveness of computerized cognitive training (CCT) in older adults. DESIGN: Randomized, controlled, double single-blind trial with parallel groups. SETTING: Community centers. SUBJECTS: Eighty-six adults between 60 and 90 years old. INTERVENTIONS: Nine face-to-face 60-min sessions of CCT with VIRTRAEL for all participants. The experimental group received an additional 30 min of Facebook training per session. MAIN MEASURES: Attention (d2 Test of Attention); learning and verbal memory (Hopkins Verbal Learning Test-Revised); working memory (Letter-Number Sequencing test), semantic and abstract reasoning (Similarities and Matrix Reasoning tests); and planning (Key Search test). RESULTS: There was a significant Group*Time interaction in the Hopkins Verbal Learning Test-Revised-Trial 3, Letter-Number sequencing, and Matrix tests. Between groups, post-hoc analyses showed a difference in Matrix reasoning (p < .001; d = 0.893) at post-intervention in favor of the experimental group. Significant main effects of time were found in the CCT group between baseline and 3-month follow-up for Concentration (F = 26.431, p ≤ .001), Letters and Numbers (F = 30.549, p ≤ .001), Learning (F = 38.678, p ≤ .001), Similarities (F = 69.885, p ≤ .001), Matrix (F = 90.342, p ≤ .001), and Key Search (F = 7.904, p = .006) tests. CONCLUSIONS: The utilization of CCT with VIRTRAEL, a freely accessible tool with broad applicability, resulted in enhanced attention, verbal learning, working memory, abstract and semantic reasoning, and planning among older adults. These improvements were sustained for at least three months post-training. Additional training in Facebook did not enhance the effectiveness of CCT.


Assuntos
Mídias Sociais , Humanos , Masculino , Idoso , Feminino , Pessoa de Meia-Idade , Método Simples-Cego , Idoso de 80 Anos ou mais , Método Duplo-Cego , Terapia Cognitivo-Comportamental/métodos , Terapia Assistida por Computador/métodos , Resultado do Tratamento , Testes Neuropsicológicos , Treino Cognitivo
2.
J Cell Physiol ; 238(5): 976-991, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36852591

RESUMO

Voltage-dependent potassium channel Kv1.3 plays a key role on T-cell activation; however, lack of reliable antibodies has prevented its accurate detection under endogenous circumstances. To overcome this limitation, we created a Jurkat T-cell line with endogenous Kv1.3 channel tagged, to determine the expression, location, and changes upon activation of the native Kv1.3 channels. CRISPR-Cas9 technique was used to insert a Flag-Myc peptide at the C terminus of the KCNA3 gene. Basal or activated channel expression was studied using western blot analysis and imaging techniques. We identified two isoforms of Kv1.3 other than the canonical channel (54 KDa) differing on their N terminus: a longer isoform (70 KDa) and a truncated isoform (43 KDa). All three isoforms were upregulated after T-cell activation. We focused on the functional characterization of the truncated isoform (short form, SF), because it has not been previously described and could be present in the available Kv1.3-/- mice models. Overexpression of SF in HEK cells elicited small amplitude Kv1.3-like currents, which, contrary to canonical Kv1.3, did not induce HEK proliferation. To explore the role of endogenous SF isoform in a native system, we generated both a knockout Jurkat clone and a clone expressing only the SF isoform. Although the canonical isoform (long form) localizes mainly at the plasma membrane, SF remains intracellular, accumulating perinuclearly. Accordingly, SF Jurkat cells did not show Kv1.3 currents and exhibited depolarized resting membrane potential (VM ), decreased Ca2+ influx, and a reduction in the [Ca2+ ]i increase upon stimulation. Functional characterization of these Kv1.3 channel isoforms showed their differential contribution to signaling pathways involved in formation of the immunological synapse. We conclude that alternative translation initiation generates at least three endogenous Kv1.3 channel isoforms in T cells that exhibit different functional roles. For some of these functions, Kv1.3 proteins do not need to form functional plasma membrane channels.


Assuntos
Canal de Potássio Kv1.3 , Animais , Humanos , Camundongos , Linhagem Celular , Membrana Celular/metabolismo , Células Jurkat , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Canal de Potássio Kv1.3/genética , Canal de Potássio Kv1.3/metabolismo
3.
J Cell Physiol ; 236(6): 4330-4347, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33230847

RESUMO

The voltage-dependent potassium channel Kv1.3 has been implicated in proliferation in many cell types, based on the observation that Kv1.3 blockers inhibited proliferation. By modulating membrane potential, cell volume, and/or Ca2+ influx, K+  channels can influence cell cycle progression. Also, noncanonical channel functions could contribute to modulate cell proliferation independent of K+ efflux. The specificity of the requirement of Kv1.3 channels for proliferation suggests the involvement of molecule-specific interactions, but the underlying mechanisms are poorly identified. Heterologous expression of Kv1.3 channels in HEK cells has been shown to increase proliferation independently of K+ fluxes. Likewise, some of the molecular determinants of Kv1.3-induced proliferation have been located in the C-terminus region, where individual point mutations of putative phosphorylation sites (Y447A and S459A) abolished Kv1.3-induced proliferation. Here, we investigated the mechanisms linking Kv1.3 channels to proliferation exploring the correlation between Kv1.3 voltage-dependent molecular dynamics and cell cycle progression. Using transfected HEK cells, we analyzed both the effect of changes in resting membrane potential on Kv1.3-induced proliferation and the effect of mutated Kv1.3 channels with altered voltage dependence of gating. We conclude that voltage-dependent transitions of Kv1.3 channels enable the activation of proliferative pathways. We also found that Kv1.3 associated with IQGAP3, a scaffold protein involved in proliferation, and that membrane depolarization facilitates their interaction. The functional contribution of Kv1.3-IQGAP3 interplay to cell proliferation was demonstrated both in HEK cells and in vascular smooth muscle cells. Our data indicate that voltage-dependent conformational changes of Kv1.3 are an essential element in Kv1.3-induced proliferation.


Assuntos
Proliferação de Células , Ativação do Canal Iônico , Canal de Potássio Kv1.3/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Células HEK293 , Humanos , Canais KATP/genética , Canais KATP/metabolismo , Canal de Potássio Kv1.3/química , Canal de Potássio Kv1.3/genética , Potenciais da Membrana , Mutação , Conformação Proteica , Transdução de Sinais , Relação Estrutura-Atividade
4.
J Neurosci Res ; 99(12): 3103-3120, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34713467

RESUMO

Fas Apoptotic Inhibitory Molecule protein (FAIM) is a death receptor antagonist and an apoptosis regulator. It encodes two isoforms, namely FAIM-S (short) and FAIM-L (long), both with significant neuronal functions. FAIM-S, which is ubiquitously expressed, is involved in neurite outgrowth. In contrast, FAIM-L is expressed only in neurons and it protects them from cell death. Interestingly, FAIM-L is downregulated in patients and mouse models of Alzheimer's disease before the onset of neurodegeneration, and Faim transcript levels are decreased in mouse models of retinal degeneration. However, few studies have addressed the role of FAIM in the central nervous system, yet alone the retina. The retina is a highly specialized tissue, and its degeneration has proved to precede pathological mechanisms of neurodegenerative diseases. Here we describe that Faim depletion in mice damages the retina persistently and leads to late-onset photoreceptor death in older mice. Immunohistochemical analyses showed that Faim knockout (Faim-/- ) mice present ubiquitinated aggregates throughout the retina from early ages. Moreover, retinal cells released stress signals that can signal to Müller cells, as shown by immunofluorescence and qRT-PCR. Müller cells monitor retinal homeostasis and trigger a gliotic response in Faim-/- mice that becomes pathogenic when sustained. In this regard, we observed pronounced vascular leakage at later ages, which may be caused by persistent inflammation. These results suggest that FAIM is an important player in the maintenance of retinal homeostasis, and they support the premise that FAIM is a plausible early marker for late photoreceptor and neuronal degeneration.


Assuntos
Proteínas Reguladoras de Apoptose , Gliose , Neurônios , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/fisiologia , Morte Celular , Gliose/patologia , Camundongos , Neurônios/metabolismo , Retina
5.
Arterioscler Thromb Vasc Biol ; 39(12): e273-e286, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31597447

RESUMO

OBJECTIVE: We have previously described that changes in the expression of Kv channels associate to phenotypic modulation (PM), so that Kv1.3/Kv1.5 ratio is a landmark of vascular smooth muscle cells phenotype. Moreover, we demonstrated that the Kv1.3 functional expression is relevant for PM in several types of vascular lesions. Here, we explore the efficacy of Kv1.3 inhibition for the prevention of remodeling in human vessels, and the mechanisms linking the switch in Kv1.3 /Kv1.5 ratio to PM. Approach and Results: Vascular remodeling was explored using organ culture and primary cultures of vascular smooth muscle cells obtained from human vessels. We studied the effects of Kv1.3 inhibition on serum-induced remodeling, as well as the impact of viral vector-mediated overexpression of Kv channels or myocardin knock-down. Kv1.3 blockade prevented remodeling by inhibiting proliferation, migration, and extracellular matrix secretion. PM activated Kv1.3 via downregulation of Kv1.5. Hence, both Kv1.3 blockers and Kv1.5 overexpression inhibited remodeling in a nonadditive fashion. Finally, myocardin knock-down induced vessel remodeling and Kv1.5 downregulation and myocardin overexpression increased Kv1.5, while Kv1.5 overexpression inhibited PM without changing myocardin expression. CONCLUSIONS: We demonstrate that Kv1.5 channel gene is a myocardin-regulated, vascular smooth muscle cells contractile marker. Kv1.5 downregulation upon PM leaves Kv1.3 as the dominant Kv1 channel expressed in dedifferentiated cells. We demonstrated that the inhibition of Kv1.3 channel function with selective blockers or by preventing Kv1.5 downregulation can represent an effective, novel strategy for the prevention of intimal hyperplasia and restenosis of the human vessels used for coronary angioplasty procedures.


Assuntos
Doença da Artéria Coronariana/genética , Vasos Coronários/patologia , Regulação da Expressão Gênica , Canal de Potássio Kv1.3/genética , Canal de Potássio Kv1.5/genética , Músculo Liso Vascular/metabolismo , Proteínas Nucleares/genética , Transativadores/genética , Células Cultivadas , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Vasos Coronários/metabolismo , Vasos Coronários/fisiopatologia , Humanos , Imuno-Histoquímica , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/biossíntese , Canal de Potássio Kv1.5/biossíntese , Músculo Liso Vascular/patologia , Proteínas Nucleares/biossíntese , Técnicas de Cultura de Órgãos , Fenótipo , RNA/genética , Transativadores/biossíntese , Remodelação Vascular
6.
Am J Physiol Cell Physiol ; 314(1): C27-C42, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28931540

RESUMO

Kv1.3 channels are involved in the switch to proliferation of normally quiescent cells, being implicated in the control of cell cycle in many different cell types and in many different ways. They modulate membrane potential controlling K+ fluxes, sense changes in potential, and interact with many signaling molecules through their intracellular domains. From a mechanistic point of view, we can describe the role of Kv1.3 channels in proliferation with at least three different models. In the "membrane potential model," membrane hyperpolarization resulting from Kv1.3 activation provides the driving force for Ca2+ influx required to activate Ca2+-dependent transcription. This model explains most of the data obtained from several cells from the immune system. In the "voltage sensor model," Kv1.3 channels serve mainly as sensors that transduce electrical signals into biochemical cascades, independently of their effect on membrane potential. Kv1.3-dependent proliferation of vascular smooth muscle cells (VSMCs) could fit this model. Finally, in the "channelosome balance model," the master switch determining proliferation may be related to the control of the Kv1.3 to Kv1.5 ratio, as described in glial cells and also in VSMCs. Since the three mechanisms cannot function independently, these models are obviously not exclusive. Nevertheless, they could be exploited differentially in different cells and tissues. This large functional flexibility of Kv1.3 channels surely gives a new perspective on their functions beyond their elementary role as ion channels, although a conclusive picture of the mechanisms involved in Kv1.3 signaling to proliferation is yet to be reached.


Assuntos
Proliferação de Células , Canal de Potássio Kv1.3/metabolismo , Potássio/metabolismo , Animais , Sinalização do Cálcio , Proliferação de Células/efeitos dos fármacos , Humanos , Ativação do Canal Iônico , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/química , Canal de Potássio Kv1.3/genética , Potenciais da Membrana , Modelos Biológicos , Bloqueadores dos Canais de Potássio/farmacologia , Conformação Proteica , Relação Estrutura-Atividade
7.
Microcirculation ; 25(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29110368

RESUMO

Kv channels are present in virtually all VSMCs and strongly influence contractile responses. However, they are also instrumental in the proliferative, migratory, and secretory functions of synthetic, dedifferentiated VSMCs upon PM. In fact, Kv channels not only contribute to all these processes but also are active players in the phenotypic switch itself. This review is focused on the role(s) of Kv channels in VSMC proliferation, which is one of the best characterized functions of dedifferentiated VSMCs. VSMC proliferation is a complex process requiring specific Kv channels at specific time and locations. Their identification is further complicated by their large diversity and the differences in expression across vascular beds. Of interest, both conserved changes in some Kv channels and vascular bed-specific regulation of others seem to coexist and participate in VSMC proliferation through complementary mechanisms. Such a system will add flexibility to the process while providing the required robustness to preserve this fundamental cellular response.


Assuntos
Proliferação de Células , Músculo Liso Vascular/citologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Animais , Humanos , Remodelação Vascular
8.
J Physiol ; 595(5): 1497-1513, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27861908

RESUMO

KEY POINTS: Canonical transient receptor potential (TRPC)3 and TRPC6 channels of vascular smooth muscle cells (VSMCs) mediate stretch- or agonist-induced cationic fluxes, contributing to membrane potential and vascular tone. Native TRPC3/C6 channels can form homo- or heterotetrameric complexes, which can hinder individual TRPC channel properties. The possibility that the differences in their association pattern may change their contribution to vascular tone in hypertension is unexplored. Functional characterization of heterologously expressed channels showed that TRPC6-containing complexes exhibited Pyr3/Pyr10-sensitive currents, whereas TRPC3-mediated currents were blocked by anti-TRPC3 antibodies. VSMCs from hypertensive (blood pressure high; BPH) mice have larger cationic basal currents insensitive to Pyr10 and sensitive to anti-TRPC3 antibodies. Consistently, myography studies showed a larger Pyr3/10-induced vasodilatation in BPN (blood pressure normal) mesenteric arteries. We conclude that the increased TRPC3 channel expression in BPH VSMCs leads to changes in TRPC3/C6 heteromultimeric assembly, with a higher TRPC3 channel contribution favouring depolarization of hypertensive VSMCs. ABSTRACT: Increased vascular tone in essential hypertension involves a sustained rise in total peripheral resistance. A model has been proposed in which the combination of membrane depolarization and higher L-type Ca2+ channel activity generates augmented Ca2+ influx into vascular smooth muscle cells (VSMCs), contraction and vasoconstriction. The search for culprit ion channels responsible for membrane depolarization has provided several candidates, including members of the canonical transient receptor potential (TRPC) family. TRPC3 and TRPC6 are diacylglycerol-activated, non-selective cationic channels contributing to stretch- or agonist-induced depolarization. Conflicting information exists regarding changes in TRPC3/TRPC6 functional expression in hypertension. However, although TRPC3-TRPC6 channels can heteromultimerize, the possibility that differences in their association pattern may change their functional contribution to vascular tone is largely unexplored. We probe this hypothesis using a model of essential hypertension (BPH mice; blood pressure high) and its normotensive control (BPN mice; blood pressure normal). First, non-selective cationic currents through homo- and heterotetramers recorded from transfected Chinese hamster ovary cells indicated that TRPC currents were sensitive to the selective antagonist Pyr10 only when TRPC6 was present, whereas intracellular anti-TRPC3 antibody selectively blocked TRPC3-mediated currents. In mesenteric VSMCs, basal and agonist-induced currents were more sensitive to Pyr3 and Pyr10 in BPN cells. Consistently, myography studies showed a larger Pyr3/10-induced vasodilatation in BPN mesenteric arteries. mRNA and protein expression data supported changes in TRPC3 and TRPC6 proportions and assembly, with a higher TRPC3 channel contribution in BPH VSMCs that could favour cell depolarization. These differences in functional and pharmacological properties of TRPC3 and TRPC6 channels, depending on their assembly, could represent novel therapeutical opportunities.


Assuntos
Hipertensão/fisiopatologia , Miócitos de Músculo Liso/fisiologia , Canais de Cátion TRPC/fisiologia , Animais , Aorta/fisiologia , Células CHO , Cricetulus , Hipertensão Essencial , Artéria Femoral/fisiologia , Artérias Mesentéricas/fisiologia , Camundongos , Músculo Liso Vascular/fisiologia , Pirazóis/farmacologia , Canais de Cátion TRPC/genética , Canal de Cátion TRPC6
9.
J Biol Chem ; 291(7): 3569-80, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26655221

RESUMO

Changes in voltage-dependent potassium channels (Kv channels) associate to proliferation in many cell types, including transfected HEK293 cells. In this system Kv1.5 overexpression decreases proliferation, whereas Kv1.3 expression increases it independently of K(+) fluxes. To identify Kv1.3 domains involved in a proliferation-associated signaling mechanism(s), we constructed chimeric Kv1.3-Kv1.5 channels and point-mutant Kv1.3 channels, which were expressed as GFP- or cherry-fusion proteins. We studied their trafficking and functional expression, combining immunocytochemical and electrophysiological methods, and their impact on cell proliferation. We found that the C terminus is necessary for Kv1.3-induced proliferation. We distinguished two residues (Tyr-447 and Ser-459) whose mutation to alanine abolished proliferation. The insertion into Kv1.5 of a sequence comprising these two residues increased proliferation rate. Moreover, Kv1.3 voltage-dependent transitions from closed to open conformation induced MEK-ERK1/2-dependent Tyr-447 phosphorylation. We conclude that the mechanisms for Kv1.3-induced proliferation involve the accessibility of key docking sites at the C terminus. For one of these sites (Tyr-447) we demonstrated the contribution of MEK/ERK-dependent phosphorylation, which is regulated by voltage-induced conformational changes.


Assuntos
Canal de Potássio Kv1.3/agonistas , Sistema de Sinalização das MAP Quinases , Processamento de Proteína Pós-Traducional , Substituição de Aminoácidos , Proliferação de Células , Células HEK293 , Humanos , Canal de Potássio Kv1.3/química , Canal de Potássio Kv1.3/genética , Canal de Potássio Kv1.3/metabolismo , Canal de Potássio Kv1.5/agonistas , Canal de Potássio Kv1.5/química , Canal de Potássio Kv1.5/genética , Canal de Potássio Kv1.5/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/antagonistas & inibidores , MAP Quinase Quinase 2/genética , MAP Quinase Quinase 2/metabolismo , Mutagênese Insercional , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fosforilação , Mutação Puntual , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Interferência de RNA , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Tirosina/metabolismo
10.
Lupus ; 25(13): 1470-1478, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27055522

RESUMO

The aim of this study was to investigate the possible effects of corticosteroids in women with systemic lupus erythematosus (SLE) in two processes of executive function: cognitive flexibility and decision-making. To that end, we evaluated 121 women divided into three groups: 50 healthy women, 38 women with SLE not receiving corticosteroid treatment and 33 women with SLE receiving corticosteroid treatment. Cognitive flexibility was measured with the Trail Making Tests A and B; decision-making was measured with the Iowa Gambling Task. Additionally, demographic (age and education level), clinical (SLE Disease Activity Index (SLEDAI), Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology (ACR) Damage Index (SDI) and disease duration) and psychological characteristics (stress vulnerability, perceived stress and psychopathic symptomatology) were evaluated. The results showed that both SLE groups displayed poorer decision-making than the healthy women ( p = 0.006) and also that the SLE group receiving corticosteroid treatment showed lower cognitive flexibility than the other two groups ( p = 0.030). Moreover, SLE patients showed poorer scores than healthy women on the following SCL-90-R subscales: somatisation ( p = 0.005), obsessions and compulsions ( p = 0.045), depression ( p = 0.004), hostility ( p = 0.013), phobic anxiety ( p = 0.005), psychoticism ( p = 0.016) and positive symptom total ( p = 0.001). In addition, both SLE groups were more vulnerable to stress ( p = 0.000). These findings help to understand the effects of corticosteroid treatment on cognitive flexibility and decision-making, in addition to the disease-specific effects suffered by women with SLE.


Assuntos
Corticosteroides/farmacologia , Cognição/efeitos dos fármacos , Tomada de Decisões/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Corticosteroides/administração & dosagem , Adulto , Feminino , Humanos , Lúpus Eritematoso Sistêmico/psicologia , Pessoa de Meia-Idade , Índice de Gravidade de Doença
11.
Arterioscler Thromb Vasc Biol ; 35(6): 1489-97, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25857312

RESUMO

OBJECTIVE: Actin dynamics in vascular smooth muscle is known to regulate contractile differentiation and may play a role in the pathogenesis of vascular disease. However, the list of genes regulated by actin polymerization in smooth muscle remains incomprehensive. Thus, the objective of this study was to identify actin-regulated genes in smooth muscle and to demonstrate the role of these genes in the regulation of vascular smooth muscle phenotype. APPROACH AND RESULTS: Mouse aortic smooth muscle cells were treated with an actin-stabilizing agent, jasplakinolide, and analyzed by microarrays. Several transcripts were upregulated including both known and previously unknown actin-regulated genes. Dystrophin and synaptopodin 2 were selected for further analysis in models of phenotypic modulation and vascular disease. These genes were highly expressed in differentiated versus synthetic smooth muscle and their expression was promoted by the transcription factors myocardin and myocardin-related transcription factor A. Furthermore, the expression of both synaptopodin 2 and dystrophin was significantly reduced in balloon-injured human arteries. Finally, using a dystrophin mutant mdx mouse and synaptopodin 2 knockdown, we demonstrate that these genes are involved in the regulation of smooth muscle differentiation and function. CONCLUSIONS: This study demonstrates novel genes that are promoted by actin polymerization, that regulate smooth muscle function, and that are deregulated in models of vascular disease. Thus, targeting actin polymerization or the genes controlled in this manner can lead to novel therapeutic options against vascular pathologies that involve phenotypic modulation of smooth muscle cells.


Assuntos
Actinas/metabolismo , Distrofina/genética , Proteínas dos Microfilamentos/genética , Músculo Liso Vascular/metabolismo , Doenças Vasculares/genética , Doenças Vasculares/metabolismo , Animais , Artérias/lesões , Células Cultivadas , Expressão Gênica , Humanos , Camundongos Endogâmicos mdx , Camundongos Knockout , Contração Muscular , Relaxamento Muscular , Polimerização , Transcrição Gênica
12.
Pflugers Arch ; 467(8): 1711-22, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25208915

RESUMO

Phenotypic modulation (PM) of vascular smooth muscle cells (VSMCs) is central to the process of intimal hyperplasia which constitutes a common pathological lesion in occlusive vascular diseases. Changes in the functional expression of Kv1.5 and Kv1.3 currents upon PM in mice VSMCs have been found to contribute to cell migration and proliferation. Using human VSMCs from vessels in which unwanted remodeling is a relevant clinical complication, we explored the contribution of the Kv1.5 to Kv1.3 switch to PM. Changes in the expression and the functional contribution of Kv1.3 and Kv1.5 channels were studied in contractile and proliferating VSMCs obtained from human donors. Both a Kv1.5 to Kv1.3 switch upon PM and an anti-proliferative effect of Kv1.3 blockers on PDGF-induced proliferation were observed in all vascular beds studied. When investigating the signaling pathways modulated by the blockade of Kv1.3 channels, we found that anti-proliferative effects of Kv1.3 blockers on human coronary artery VSMCs were occluded by selective inhibition of MEK/ERK and PLCγ signaling pathways, but were unaffected upon blockade of PI3K/mTOR pathway. The temporal course of the anti-proliferative effects of Kv1.3 blockers indicates that they have a role in the late signaling events essential for the mitogenic response to growth factors. These findings establish the involvement of Kv1.3 channels in the PM of human VSMCs. Moreover, as current therapies to prevent restenosis rely on mTOR blockers, our results provide the basis for the development of novel, more specific therapies.


Assuntos
Proliferação de Células , Músculo Liso Vascular/enzimologia , Miócitos de Músculo Liso/enzimologia , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/genética , Canal de Potássio Kv1.3/metabolismo , Canal de Potássio Kv1.5/genética , Canal de Potássio Kv1.5/metabolismo , Potenciais da Membrana , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Fenótipo , Inibidores de Fosfodiesterase/farmacologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Fatores de Tempo
13.
Lupus ; 24(8): 875-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25697771

RESUMO

OBJECTIVE: To analyze the role of the antiphospholipid autoantibodies (aPL) on the neuropsychological deficits in systemic lupus erythematosus (SLE) patients, comparing groups of patients with antiphospholipid syndrome (APS; n = 15), SLE with aPL (n = 12), and SLE without aPL (n = 27), and a healthy control group (n = 31). METHODS: Patients fulfilled the American College of Rheumatology SLE classification criteria or the Sydney criteria for APS. All participants were woman, and groups were matched on age and education. A standardized cognitive examination classified patients as cognitively declined or impaired according to the American College of Rheumatology. RESULTS: Differences between the groups were found in all of the studied variables, comprising attention and executive functions (sustained and selective attention, fluency, and inhibition), and memory (verbal and visual). Post-hoc analyses showed cognitive performance was equivalent between APS and SLE with aPL. Differences between SLE without aPL and control groups were found only in four of the 10 studied variables, while differences in all but two memory variables were found between SLE without aPL and control groups. Furthermore, cognitive deficit was three times more frequent in APS and SLE with aPL patients than for the control group (80%, 75%, and 16%, respectively), and two times more frequent compared to SLE patients without aPL (48%). CONCLUSIONS: Our results support the relationship between aPL and cognitive symptoms in SLE. Also, almost half of the patients with SLE and no aPL showed cognitive problems, pointing to the multifactorial causes of cognitive problems in SLE. Future research with larger sample size is guaranteed to replicate our results.


Assuntos
Anticorpos Antifosfolipídeos/imunologia , Síndrome Antifosfolipídica/imunologia , Transtornos Cognitivos/epidemiologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/imunologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/psicologia , Adulto , Atenção , Função Executiva , Feminino , Humanos , Memória , Pessoa de Meia-Idade
14.
Neurocase ; 20(4): 421-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23668221

RESUMO

In a patient with a lesion of the right amygdala and temporal pole who had the characteristics of the gourmand syndrome, sensory and hedonic testing was performed to examine the processing of taste, olfactory, and some emotional stimuli. The gourmand syndrome describes a preoccupation with food and a preference for fine eating and is associated with right anterior lesions. It was found that the taste thresholds for sweet, salt, bitter, and sour were normal; that the patient did not dislike the taste of salt (NaCl) at low and moderate concentrations as much as age-matched controls; that this also occurred for monosodium glutamate (MSG); that there were some olfactory differences from normal controls; and that there was a marked reduction in the ability to detect face expressions of disgust.


Assuntos
Tonsila do Cerebelo/patologia , Transtornos da Alimentação e da Ingestão de Alimentos/patologia , Olfato/fisiologia , Paladar/fisiologia , Emoções , Expressão Facial , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Humanos , Masculino , Meningioma/complicações , Meningioma/patologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Limiar Sensorial/fisiologia , Limiar Gustativo/fisiologia
15.
Cardiovasc Drugs Ther ; 28(6): 501-11, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25348824

RESUMO

INTRODUCTION: K(+) channels are central to vascular pathophysiology. Previous results demonstrated that phenotypic modulation associates with a change in Kv1.3 to Kv1.5 expression, and that Kv1.3 blockade inhibits proliferation of VSMCs cultures. PURPOSE: To explore whether the Kv1.3 to Kv1.5 switch could be a marker of the increased risk of intimal hyperplasia in essential hypertension and whether systemic treatment with Kv1.3 blockers can prevent intimal hyperplasia after endoluminal lesion . METHODS: Morphometric and immunohistochemical analysis were performed in arterial segments following arterial injury and constant infusion of the Kv1.3 blocker PAP-1 during 28 days. Differential expression of K(+) channel genes was studied in VSMC from hypertensive (BPH) and normotensive (BPN) mice, both in control and after endoluminal lesion. Finally, the migration and proliferation rate of BPN and BPH VSMCs was explored in vitro. RESULTS: Changes in mRNA expression led to an increased Kv1.3/Kv1.5 ratio in BPH VSMC. Consistent with this, arterial injury in BPH mice induced a higher degree of luminal stenosis, (84 ± 4% vs. 70 ± 5% in BPN, p < 0.01), although no differences in migration and proliferation rate were observed in cultured VSMCs. The in vivo proliferative lesions were significantly decreased upon PAP-1 systemic infusion (18 ± 6% vs. 58 ± 20% with vehicle, p < 0.05). CONCLUSIONS: Hypertension leads to a higher degree of luminal stenosis in our arterial injury model, that correlates with a decreased expression of Kv1.5 channels. Kv1.3 blockers decreased in vitro VSMCs proliferation, migration, and in vivo intimal hyperplasia formation, pointing to Kv1.3 channels as promising therapeutical targets against restenosis.


Assuntos
Artérias/efeitos dos fármacos , Hiperplasia/metabolismo , Hipertensão/metabolismo , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Túnica Íntima/efeitos dos fármacos , Animais , Artérias/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Hipertensão Essencial , Feminino , Hiperplasia/tratamento farmacológico , Hipertensão/tratamento farmacológico , Masculino , Camundongos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Proteínas Associadas a Pancreatite , Túnica Íntima/metabolismo
16.
Hipertens Riesgo Vasc ; 41(1): 62-65, 2024.
Artigo em Espanhol | MEDLINE | ID: mdl-38402070

RESUMO

Post-COVID-19 syndrome is a set of symptoms and signs that persist for more than 12 weeks after COVID-19 infection and currently lacks a standardised clinical definition. Only one case has been reported in which a pheochromocytoma was mistaken for post-COVID-19 syndrome. The symptomatology of this syndrome is variable and ranges from headache and fatigue to persistent dyspnoea and neurocognitive disturbances. In addition, SARS-CoV-2 can affect the autonomic nervous system, contributing to symptoms resembling those of pheochromocytoma. The importance and need to discern between COVID-19-related symptoms and other conditions is emphasised, as the specificity of the clinical manifestations of post-COVID-19 syndrome is very low and can be confused with other vital pathologies. A case is presented in which a pheochromocytoma was mistaken for post-COVID-19 syndrome in a patient with no medical history.


Assuntos
Neoplasias das Glândulas Suprarrenais , COVID-19 , Hipertensão , Feocromocitoma , Humanos , COVID-19/complicações , COVID-19/diagnóstico , Feocromocitoma/complicações , Feocromocitoma/diagnóstico , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/diagnóstico , Cefaleia/etiologia , Hipertensão/diagnóstico , Hipertensão/etiologia
17.
Rev Neurol ; 79(6): 175-178, 2024 Sep 16.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-39267403

RESUMO

INTRODUCTION: Aortic arch complex atheromatosis is a source of cerebral embolism. A percentage of lacunar infarct could be of embolic etiology, especially due to microemboli of the aortic arch. CASE REPORT: We present the case of a 63-year-old hypertensive man suffering from dysarthria-clumsy hand syndrome for a right hemispheric minor ischemic stroke. The patient developed sequential acute thromboembolism of the left lower and right upper limbs. Computed tomography angiography revealed an aortic arch thrombus. Vascular surgery was successfully performed. CONCLUSION: This case highlights the importance of considering embolic sources in lacunar syndromes, especially at the level of the aortic arch.


TITLE: Síndrome de disartria-mano torpe y embolias agudas secuenciales múltiples de las extremidades como forma de presentación de un trombo del cayado aórtico.Introducción. La ateromatosis del complejo del arco aórtico es una fuente de embolia cerebral. Un porcentaje de infartos lacunares podría ser de etiología embólica, especialmente debidos a microembolias del arco aórtico. Caso clínico. Presentamos el caso de un varón hipertenso de 63 años con síndrome de disartria-mano torpe por un ictus isquémico minor hemisférico derecho. El paciente desarrolló un tromboembolismo agudo secuencial de los miembros inferior izquierdo y superior derecho. La angiografía por tomografía computarizada reveló un trombo en el arco aórtico. La cirugía vascular se llevó a cabo con éxito. Conclusión. Este caso destaca la importancia de considerar las fuentes embólicas en los síndromes lacunares, especialmente en el arco aórtico.


Assuntos
Aorta Torácica , Disartria , Humanos , Masculino , Pessoa de Meia-Idade , Disartria/etiologia , Aorta Torácica/diagnóstico por imagem , Mãos/irrigação sanguínea , Síndrome , Doença Aguda , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/complicações
18.
Function (Oxf) ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39322240

RESUMO

Essential hypertension (HT) is a highly prevalent cardiovascular disease of unclear physiopathology. Pharmacological studies suggest that purinergic P2Y6 receptors (P2ry6) play important roles in cardiovascular function and may contribute to angiotensin II (AgtII) pathophysiological effects. Here, we tested the hypothesis that functional coupling between P2ry6 and AgtII receptors mediates altered vascular reactivity in HT. For this, a multipronged approach was implemented using mesenteric vascular smooth muscle cells (VSMCs) and arteries from BPN (Blood Pressure Normal) and BPH (Blood Pressure High) mice. Differential transcriptome profiling of mesenteric artery VSMCs identified P2ry6 purinergic receptor mRNA as one of the top upregulated transcripts in BPH. P2Y receptor activation elicited distinct vascular responses in mesenteric arteries from BPN and BPH mice. Accordingly, 10 µM UTP produced a contraction close to half-maximal activation in BPH arteries but no response in BPN vessels. AgtII-induced contraction was also higher in BPH mice despite having lower AgtII receptor type-1 (Agtr1) expression and was sensitive to P2ry6 modulators. Proximity Ligation Assay (PLA) and super-resolution microscopy (SRM) showed closer localization of Agtr1 and P2ry6 at/near the membrane of BPH mice. This proximal association was reduced in BPN mice, suggesting a functional role for Agtr1-P2ry6 complexes in the hypertensive phenotype. Intriguingly, BPN mice were resistant to AgtII-induced HT and showed reduced P2ry6 expression in VSMCs. Altogether, results suggest that increased functional coupling between P2ry6 and Agtr1 may contribute to enhanced vascular reactivity during HT. In this regard, blocking P2ry6 could be a potential pharmacological strategy to treat HT.

19.
Sci Rep ; 14(1): 20753, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237591

RESUMO

Currently, there are no national and international certified reference materials (CRM) in lithium clays that can make reliable and traceable lithium measurements for the International System of Units (SI). Hence, it is necessary to have references to meet the needs in terms of mining and activities that involve the use of lithium to favor the economy derived from its multiple uses and associated benefits in the exploration, exploitation, and handling of lithium ore. In this study, a candidate for reference material (RM) of Li in clays was developed and certified based on the provisions of ISO 17034:2016 and ISO Guide 35:2017. Different mass sizes of the RM (0.05, 0.1, and 0.25 g) were used to evaluate homogeneity. An isochronous study (short-term stability) was carried out in the assessment of stability, influenced by the effects of transport at different temperatures (20, 40, and 50 °C) for a determined time of 6 weeks, in addition to a classic (long-term) study for 19 weeks. The sample was treated using microwave-assisted acid digestion and Li measurements were performed using the analytical technique of Flame Atomic Absorption Spectrometry (FAAS). The CRM is homogeneous for the sample mass sizes of 0.05 and 0.1 g, and the mass fraction of w(Li) was stable in the RM for temperatures of 20, 40, and 50 °C. The determined period of validity was 3 years.

20.
J Physiol ; 591(24): 6175-91, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24167226

RESUMO

Hypertension is a clinical syndrome characterized by increased arterial tone. Although the mechanisms are varied, the generally accepted view is that increased CaV1.2 channel function is a common feature of this pathological condition. Here, we investigated the mechanisms underlying vascular dysfunction in a mouse model of genetic hypertension. Contrary to expectation, we found that whole-cell CaV1.2 currents (ICa) were lower in hypertensive (BPH line) than normotensive (BPN line) myocytes. However, local CaV1.2 sparklet activity was higher in BPH cells, suggesting that the relatively low ICa in these cells was produced by a few hyperactive CaV1.2 channels. Furthermore, our data suggest that while the lower expression of the pore-forming α1c subunit of CaV1.2 currents underlies the lower ICa in BPH myocytes, the increased sparklet activity was due to a different composition in the auxiliary subunits of the CaV1.2 complexes. ICa currents in BPN cells were produced by channels composed of α1c/α2δ/ß3 subunits, while in BPH myocytes currents were probably generated by the opening of channels formed by α1c/α2δ/ß2 subunits. In addition, Ca(2+) sparks evoked large conductance, Ca(2+)-activated K(+) (BK) currents of lower magnitude in BPH than in BPN myocytes, because BK channels were less sensitive to Ca(2+). Our data are consistent with a model in which a decrease in the global number of CaV1.2 currents coexist with the existence of a subpopulation of highly active channels that dominate the resting Ca(2+) influx. The decrease in BK channel activity makes the hyperpolarizing brake ineffective and leads BPH myocytes to a more contracted resting state.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Cálcio/metabolismo , Regulação para Baixo , Hipertensão/metabolismo , Miócitos de Músculo Liso/metabolismo , Potenciais de Ação , Animais , Canais de Cálcio Tipo L/genética , Sinalização do Cálcio , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Camundongos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/fisiologia , Subunidades Proteicas/metabolismo
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