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1.
Semin Cell Dev Biol ; 144: 87-96, 2023 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-36182613

RESUMO

Infectious diseases worldwide affect human health and have important societal impacts. A better understanding of infectious diseases is urgently needed. In vitro and in vivo infection models have brought notable contributions to the current knowledge of these diseases. Organoids are multicellular culture systems resembling tissue architecture and function, recapitulating many characteristics of human disease and elucidating mechanisms of host-infectious agent interactions in the respiratory and gastrointestinal systems, the central nervous system and the skin. Here, we discuss the applicability of the organoid technology for modeling pathogenesis, host response and features, which can be explored for the development of preventive and therapeutic treatments.


Assuntos
Doenças Transmissíveis , Organoides , Humanos , Trato Gastrointestinal
2.
BMC Neurosci ; 23(1): 32, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641906

RESUMO

BACKGROUND: Fragile X syndrome, the major cause of inherited intellectual disability among men, is due to deficiency of the synaptic functional regulator FMR1 protein (FMRP), encoded by the FMRP translational regulator 1 (FMR1) gene. FMR1 alternative splicing produces distinct transcripts that may consequently impact FMRP functional roles. In transcripts without exon 14 the translational reading frame is shifted. For deepening current knowledge of the differential expression of Fmr1 exon 14 along the rat nervous system development, we conducted a descriptive study employing quantitative RT-PCR and BLAST of RNA-Seq datasets. RESULTS: We observed in the rat forebrain progressive decline of total Fmr1 mRNA from E11 to P112 albeit an elevation on P3; and exon-14 skipping in E17-E20 with downregulation of the resulting mRNA. We tested if the reduced detection of messages without exon 14 could be explained by nonsense-mediated mRNA decay (NMD) vulnerability, but knocking down UPF1, a major component of this pathway, did not increase their quantities. Conversely, it significantly decreased FMR1 mRNA having exon 13 joined with either exon 14 or exon 15 site A. CONCLUSIONS: The forebrain in the third embryonic week of the rat development is a period with significant skipping of Fmr1 exon 14. This alternative splicing event chronologically precedes a reduction of total Fmr1 mRNA, suggesting that it may be part of combinatorial mechanisms downregulating the gene's expression in the late embryonic period. The decay of FMR1 mRNA without exon 14 should be mediated by a pathway different from NMD. Finally, we provide evidence of FMR1 mRNA stabilization by UPF1, likely depending on FMRP.


Assuntos
Processamento Alternativo , Proteína do X Frágil da Deficiência Intelectual , Prosencéfalo , Processamento Alternativo/genética , Animais , Desenvolvimento Embrionário , Éxons/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Prosencéfalo/embriologia , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Mensageiro/metabolismo , Ratos , Transativadores/genética , Transativadores/metabolismo
3.
IUBMB Life ; 74(8): 763-779, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35384262

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by gradual deterioration of cognitive function, memory, and inability to perform daily, social, or occupational activities. Its etiology is associated with the accumulation of ß-amyloid peptides, phosphorylated tau protein, and neuroinflammatory and oxidative processes in the brain. Currently, there is no successful pharmacological treatment for AD. The few approved drugs are mainly aimed at treating the symptoms; however, due to the increasing discovery of etiopathological factors, there are great efforts to find new multifunctional molecules to slow down the course of this neurodegenerative disease. The commercial Ginkgo biloba formulation EGb 761® and Huperzine A, an alkaloid present in the plant Huperzia serrata, have shown in clinical trials to possess cholinergic and neuroprotective activities, including improvement in cognition, activities of daily living, and neuropsychiatric symptoms in AD patients. The purpose of this review is to expose the positive results of intervention with EGb 761® and Huperzine in patients with mild to moderate AD in the last 10 years, highlighting the pharmacological functions that justify their use in AD therapy.


Assuntos
Doença de Alzheimer , Ginkgolídeos/uso terapêutico , Atividades Cotidianas , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Ginkgolídeos/farmacologia , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Sesquiterpenos/farmacologia , Sesquiterpenos/uso terapêutico
4.
Mol Psychiatry ; 26(4): 1044-1059, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33328588

RESUMO

Scientists and health professionals are exhaustively trying to contain the coronavirus disease 2019 (COVID-19) pandemic by elucidating viral invasion mechanisms, possible drugs to prevent viral infection/replication, and health cares to minimize individual exposure. Although neurological symptoms are being reported worldwide, neural acute and long-term consequences of SARS-CoV-2 are still unknown. COVID-19 complications are associated with exacerbated immunoinflammatory responses to SARS-CoV-2 invasion. In this scenario, pro-inflammatory factors are intensely released into the bloodstream, causing the so-called "cytokine storm". Both pro-inflammatory factors and viruses may cross the blood-brain barrier and enter the central nervous system, activating neuroinflammatory responses accompanied by hemorrhagic lesions and neuronal impairment, which are largely described processes in psychiatric disorders and neurodegenerative diseases. Therefore, SARS-CoV-2 infection could trigger and/or worse brain diseases. Moreover, patients with central nervous system disorders associated to neuroimmune activation (e.g. depression, Parkinson's and Alzheimer's disease) may present increased susceptibility to SARS-CoV-2 infection and/or achieve severe conditions. Elevated levels of extracellular ATP induced by SARS-CoV-2 infection may trigger hyperactivation of P2X7 receptors leading to NLRP3 inflammasome stimulation as a key mediator of neuroinvasion and consequent neuroinflammatory processes, as observed in psychiatric disorders and neurodegenerative diseases. In this context, P2X7 receptor antagonism could be a promising strategy to prevent or treat neurological complications in COVID-19 patients.


Assuntos
Encefalopatias/complicações , Encefalopatias/patologia , COVID-19/complicações , COVID-19/patologia , Neuroimunomodulação , Receptores Purinérgicos P2X7/metabolismo , SARS-CoV-2/patogenicidade , Encefalopatias/tratamento farmacológico , Encefalopatias/metabolismo , COVID-19/imunologia , COVID-19/metabolismo , Humanos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Pandemias , SARS-CoV-2/imunologia
5.
Mol Psychiatry ; 26(6): 2633-2650, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32350390

RESUMO

Calcium, the most versatile second messenger, regulates essential biology including crucial cellular events in embryogenesis. We investigated impacts of calcium channels and purinoceptors on neuronal differentiation of normal mouse embryonic stem cells (ESCs), with outcomes being compared to those of in vitro models of Huntington's disease (HD). Intracellular calcium oscillations tracked via real-time fluorescence and luminescence microscopy revealed a significant correlation between calcium transient activity and rhythmic proneuronal transcription factor expression in ESCs stably expressing ASCL-1 or neurogenin-2 promoters fused to luciferase reporter genes. We uncovered that pharmacological manipulation of L-type voltage-gated calcium channels (VGCCs) and purinoceptors induced a two-step process of neuronal differentiation. Specifically, L-type calcium channel-mediated augmentation of spike-like calcium oscillations first promoted stable expression of ASCL-1 in differentiating ESCs, which following P2Y2 purinoceptor activation matured into GABAergic neurons. By contrast, there was neither spike-like calcium oscillations nor responsive P2Y2 receptors in HD-modeling stem cells in vitro. The data shed new light on mechanisms underlying neurogenesis of inhibitory neurons. Moreover, our approach may be tailored to identify pathogenic triggers of other developmental neurological disorders for devising targeted therapies.


Assuntos
Doença de Huntington , Células-Tronco Neurais , Trifosfato de Adenosina , Animais , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio , Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Neurônios GABAérgicos/metabolismo , Doença de Huntington/genética , Camundongos , Células-Tronco Neurais/metabolismo , Neurogênese
6.
Semin Cell Dev Biol ; 95: 25-33, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30529426

RESUMO

Calcium is an ubiquitous second messenger used by any living cell. The fine-tuning of intracellular free calcium concentration ([Ca2+]i) homeostasis and signalling pathways is crucial for the maintenance of the healthy organism. Many alterations in the homeostasis can be compensated by robust mechanisms; however, cells that already present some debility in those mechanisms, or that are over stimulated cannot compensate the stress and die. Many neurological diseases show [Ca2+] disbalance as trigger of apoptotic response resulting in massive neuronal loss and the neurodegeneration. In this review, we focus on presenting similarities and differences of neurological disorders like Huntington's, Parkinson's, Alzheimer's disease and schizophrenia and the current clinical trial status. Moreover, we describe the importance of Ca2+ signalling in neurogenesis, showing that interference of this signalling could go along with stem cell therapy in the central nervous system.


Assuntos
Sinalização do Cálcio , Doenças do Sistema Nervoso/metabolismo , Neurogênese , Animais , Humanos , Regeneração Nervosa , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo
7.
Semin Cell Dev Biol ; 95: 12-24, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30578863

RESUMO

Neurogenesis is the process by which new neurons are generated in the brain. Neural stem cells (NSCs) are differentiated into neurons, which are integrated into the neural network. Nowadays, pluripotent stem cells, multipotent stem cells, and induced pluripotent stem cells can be artificially differentiated into neurons utilizing several techniques. Specific transcriptional profiles from NSCs during differentiation are frequently used to approach and observe phenotype alteration and functional determination of neurons. In this context, the role of non-coding RNA, transcription factors and epigenetic changes in neuronal development and differentiation has gained importance. Epigenetic elucidation has become a field of intense research due to distinct patterns of normal conditions and different neurodegenerative disorders, which can be explored to develop new diagnostic methods or gene therapies. In this review, we discuss the complexity of transcription factors, non-coding RNAs, and extracellular vesicles that are responsible for guiding and coordinating neural development.


Assuntos
Diferenciação Celular/genética , Epigênese Genética , Neurônios/citologia , Neurônios/metabolismo , Transdução de Sinais/genética , Animais , Exossomos/metabolismo , Humanos , RNA não Traduzido/genética , RNA não Traduzido/metabolismo
8.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207177

RESUMO

Huntington's disease (HD) is a multi-system disorder that is caused by expanded CAG repeats within the exon-1 of the huntingtin (HTT) gene that translate to the polyglutamine stretch in the HTT protein. HTT interacts with the proteins involved in gene transcription, endocytosis, and metabolism. HTT may also directly or indirectly affect purine metabolism and signaling. We aimed to review existing data and discuss the modulation of the purinergic system as a new therapeutic target in HD. Impaired intracellular nucleotide metabolism in the HD affected system (CNS, skeletal muscle and heart) may lead to extracellular accumulation of purine metabolites, its unusual catabolism, and modulation of purinergic signaling. The mechanisms of observed changes might be different in affected systems. Based on collected findings, compounds leading to purine and ATP pool reconstruction as well as purinergic receptor activity modulators, i.e., P2X7 receptor antagonists, may be applied for HD treatment.


Assuntos
Doença de Huntington/metabolismo , Nucleotídeos de Purina/metabolismo , Transdução de Sinais , AMP Desaminase/antagonistas & inibidores , AMP Desaminase/metabolismo , Animais , Inibidores Enzimáticos/uso terapêutico , Humanos , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/tratamento farmacológico , Doença de Huntington/genética , Fármacos Neuroprotetores/uso terapêutico
9.
Cytometry A ; 97(11): 1109-1126, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32633884

RESUMO

Tumor-associated macrophages are widely recognized for their importance in guiding pro-tumoral or antitumoral responses. Mediating inflammation or immunosuppression, these cells support many key events in cancer progression: cell growth, chemotaxis, invasiveness, angiogenesis and cell death. The communication between cells in the tumor microenvironment strongly relies on the secretion and recognition of several molecules, including damage-associated molecular patterns (DAMPs), such as adenosine triphosphate (ATP). Extracellular ATP (eATP) and its degradation products act as signaling molecules and have extensively described roles in immune response and inflammation, as well as in cancer biology. These multiple functions highlight the purinergic system as a promising target to investigate the interplay between macrophages and cancer cells. Here, we reviewed purinergic signaling pathways connecting cancer cells and macrophages, a yet poorly investigated field. Finally, we present a new tool for the characterization of macrophage phenotype within the tumor. Image cytometry emerges as a cutting-edge tool, capable of providing a broad set of information on cell morphology, expression of specific markers, and its cellular or subcellular localization, preserving cell-cell interactions within the tumor section and providing high statistical strength in small-sized experiments. Thus, image cytometry allows deeper investigation of tumor heterogeneity and interactions between these cells. © 2020 International Society for Advancement of Cytometry.


Assuntos
Microambiente Tumoral , Macrófagos Associados a Tumor , Trifosfato de Adenosina , Humanos , Macrófagos , Transdução de Sinais
10.
Adv Exp Med Biol ; 1201: 275-353, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31898792

RESUMO

Extracellular purines exert several functions in physiological and pathophysiological mechanisms. ATP acts through P2 receptors as a neurotransmitter and neuromodulator and modulates heart contractility, while adenosine participates in neurotransmission, blood pressure, and many other mechanisms. Because of their capability to differentiate into mature cell types, they provide a unique therapeutic strategy for regenerating damaged tissue, such as in cardiovascular and neurodegenerative diseases. Purinergic signaling is pivotal for controlling stem cell differentiation and phenotype determination. Proliferation, differentiation, and apoptosis of stem cells of various origins are regulated by purinergic receptors. In this chapter, we selected neurodegenerative and cardiovascular diseases with clinical trials using cell therapy and purinergic receptor targeting. We discuss these approaches as therapeutic alternatives to neurodegenerative and cardiovascular diseases. For instance, promising results were demonstrated in the utilization of mesenchymal stem cells and bone marrow mononuclear cells in vascular regeneration. Regarding neurodegenerative diseases, in general, P2X7 and A2A receptors mostly worsen the degenerative state. Stem cell-based therapy, mainly through mesenchymal and hematopoietic stem cells, showed promising results in improving symptoms caused by neurodegeneration. We propose that purinergic receptor activity regulation combined with stem cells could enhance proliferative and differentiation rates as well as cell engraftment.


Assuntos
Doenças Cardiovasculares/terapia , Doenças Neurodegenerativas/terapia , Antagonistas Purinérgicos/uso terapêutico , Receptores Purinérgicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transplante de Células-Tronco , Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Humanos , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Antagonistas Purinérgicos/farmacologia
11.
Int J Mol Sci ; 20(11)2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31174279

RESUMO

Stress exposure is considered to be the main environmental cause associated with the development of depression. Due to the limitations of currently available antidepressants, a search for new pharmacological targets for treatment of depression is required. Recent studies suggest that adenosine triphosphate (ATP)-mediated signaling through the P2X7 receptor (P2X7R) might play a prominent role in regulating depression-related pathology, such as synaptic plasticity, neuronal degeneration, as well as changes in cognitive and behavioral functions. P2X7R is an ATP-gated cation channel localized in different cell types in the central nervous system (CNS), playing a crucial role in neuron-glia signaling. P2X7R may modulate the release of several neurotransmitters, including monoamines, nitric oxide (NO) and glutamate. Moreover, P2X7R stimulation in microglia modulates the innate immune response by activating the NLR family pyrin domain containing 3 (NLRP3) inflammasome, consistent with the neuroimmune hypothesis of MDD. Importantly, blockade of P2X7R leads to antidepressant-like effects in different animal models, which corroborates the findings that the gene encoding for the P2X7R is located in a susceptibility locus of relevance to depression in humans. This review will discuss recent findings linked to the P2X7R involvement in stress and MDD neuropathophysiology, with special emphasis on neurochemical, neuroimmune, and neuroplastic mechanisms.


Assuntos
Depressão/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Transdução de Sinais , Estresse Psicológico/metabolismo , Animais , Encéfalo/metabolismo , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neurotransmissores/metabolismo
12.
J Cell Sci ; 129(18): 3437-48, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27528403

RESUMO

During brain development, cells proliferate, migrate and differentiate in highly accurate patterns. In this context, published results indicate that bradykinin functions in neural fate determination, favoring neurogenesis and migration. However, mechanisms underlying bradykinin function are yet to be explored. Our findings indicate a previously unidentified role for bradykinin action in inducing neuron-generating division in vitro and in vivo, given that bradykinin lengthened the G1-phase of the neural progenitor cells (NPC) cycle and increased TIS21 (also known as PC3 and BTG2) expression in hippocampus from newborn mice. This role, triggered by activation of the kinin-B2 receptor, was conditioned by ERK1/2 activation. Moreover, immunohistochemistry analysis of hippocampal dentate gyrus showed that the percentage of Ki67(+) cells markedly increased in bradykinin-treated mice, and ERK1/2 inhibition affected this neurogenic response. The progress of neurogenesis depended on sustained ERK phosphorylation and resulted in ERK1/2 translocation to the nucleus in NPCs and PC12 cells, changing expression of genes such as Hes1 and Ngn2 (also known as Neurog2). In agreement with the function of ERK in integrating signaling pathways, effects of bradykinin in stimulating neurogenesis were reversed following removal of protein kinase C (PKC)-mediated sustained phosphorylation.


Assuntos
Bradicinina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/enzimologia , Neurônios/metabolismo , Animais , Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , AMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Células PC12 , Fenótipo , Fosforilação/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos
13.
Cytometry A ; 89(4): 365-75, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26671187

RESUMO

The most aggressive subtype of brain tumors is glioma WHO grade IV, the glioblastoma (GBM). The present work aims to elucidate the role of kinin receptors in interactions between GBM cells and mesenchymal stem cells (MSC). The GBM cell line U87-MG was stably transfected to express dsRed protein, single cell cloned, expanded, and cultured with MSC, both in the direct co-cultures (DC) and indirect co-cultures (IC) at equal cell number ratio for 72 h. Up- and down-regulation of matrix metalloproteases (MMP)-9 expression in U87-MG and MSC cells, respectively, in direct co-culture points to possible MSC participation in tumor invasion. MMP9 expression is in line with significantly increased expression of kinin B1 (B1R) and B2 receptor (B2R) in U87-MG cells and their decreased levels in MSC, as confirmed by quantitative assessment using flow cytometric analysis. Similarly, in indirect cultures (IC), lacking the contact between GBM and MSC cells, an increase of B1 and B2 receptor expression was again noted in U87-MG cells, and no significant changes in kinin receptors in MSC was observed. Functionality of kinin-B1 and B2 receptors was evidenced by stimulation of intracellular calcium fluxes by their respective agonists, des-Arg9-bradykinin (DBK) and bradykinin (BK). Moreover, BK showed a feedback control on kinin receptor expression in mono-cultures, direct and indirect co-cultures. The treatment with BK resulted in down-regulation of B1 and B2 receptors in MSC, with simultaneous up-regulation of these receptors in U87-MG cells, suggesting that functions of BK in information flow between these cells is important for tumor progression and invasion. © 2015 International Society for Advancement of Cytometry.


Assuntos
Bradicinina/metabolismo , Glioblastoma/metabolismo , Células-Tronco Mesenquimais/citologia , Receptores da Bradicinina/metabolismo , Comunicação Celular , Células Cultivadas , Técnicas de Cocultura , Humanos , Transdução de Sinais/fisiologia , Regulação para Cima
14.
Eukaryot Cell ; 14(9): 958-63, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26150416

RESUMO

Phototaxis in flagellated zoospores of the aquatic fungus Blastocladiella emersonii depends on a novel photosensor, Blastocladiella emersonii GC1 (BeGC1), comprising a type I (microbial) rhodopsin fused to a guanylyl cyclase catalytic domain, that produces the conserved second messenger cyclic GMP (cGMP). The rapid and transient increase in cGMP levels during the exposure of zoospores to green light was shown to be necessary for phototaxis and dependent on both rhodopsin function and guanylyl cyclase activity. It is noteworthy that BeGC1 was localized to the zoospore eyespot apparatus, in agreement with its role in the phototactic response. A putative cyclic nucleotide-gated channel (BeCNG1) was also identified in the genome of the fungus and was implicated in flagellar beating via the action of a specific inhibitor (l-cis-diltiazem) that compromised zoospore motility. Here we show that B. emersonii expresses a K(+) channel that is activated by cGMP. The use of specific channel inhibitors confirmed the activation of the channel by cGMP and its K(+) selectivity. These characteristics are consistent with the function of an ion channel encoded by the BeCNG1 gene. Other blastocladiomycete fungi, such as Allomyces macrogynus and Catenaria anguillulae, possess genes encoding a similar K(+) channel and the rhodopsin-guanylyl cyclase fusion protein, while the genes encoding both these proteins are absent in nonflagellated fungi. The presence of these genes as a pair seems to be an exclusive feature of blastocladiomycete fungi. Taken together, these data demonstrate that the B. emersonii cGMP-activated K(+) channel is involved in the control of zoospore motility, most probably participating in the cGMP-signaling pathway for the phototactic response of the fungus.


Assuntos
Blastocladiomycota/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Proteínas Fúngicas/metabolismo , Canais de Potássio/metabolismo , Blastocladiomycota/genética , Blastocladiomycota/fisiologia , GMP Cíclico/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Proteínas Fúngicas/genética , Potenciais da Membrana , Potássio/metabolismo , Canais de Potássio/genética , Esporos Fúngicos/metabolismo
15.
Mol Cancer ; 14: 201, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26597723

RESUMO

BACKGROUND: One of the challenging problems of current radio-chemotherapy is recurrence and metastasis of cancer cells that survive initial treatment. We propose that one of the unwanted effects of radiochemotherapy is the release from damaged ("leaky") cells of nucleotides such as ATP and UTP that exert pro-metastatic functions and can directly stimulate chemotaxis of cancer cells. METHODS: To address this problem in a model of human lung cancer (LC), we employed several complementary in vitro and in vivo approaches to demonstrate the role of extracellular nucleotides (EXNs) in LC cell line metastasis and tumor progression. We measured concentrations of EXNs in several organs before and after radiochemotherapy. The purinergic receptor agonists and antagonists, inhibiting all or selected subtypes of receptors, were employed in in vitro and in vivo pro-metastatic assays. RESULTS: We found that EXNs accumulate in several organs in response to radiochemotherapy, and RT-PCR analysis revealed that most of the P1 and P2 receptor subtypes are expressed in human LC cells. EXNs were found to induce chemotaxis and adhesion of LC cells, and an autocrine loop was identified that promotes the proliferation of LC cells. Most importantly, metastasis of these cells could be inhibited in immunodeficient mice in the presence of specific small molecule inhibitors of purinergic receptors. CONCLUSIONS: Based on this result, EXNs are novel pro-metastatic factors released particularly during radiochemotherapy, and inhibition of their pro-metastatic effects via purinergic signaling could become an important part of anti-metastatic treatment.


Assuntos
Trifosfato de Adenosina/fisiologia , Fatores Quimiotáticos/fisiologia , Quimiotaxia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/patologia , Animais , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Quimiorradioterapia/efeitos adversos , Líquido Extracelular/fisiologia , Fator de Crescimento de Hepatócito/fisiologia , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/prevenção & controle , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Camundongos Endogâmicos C57BL , Camundongos SCID , Antagonistas de Receptores Purinérgicos P1/farmacologia , Antagonistas do Receptor Purinérgico P2/farmacologia , Receptores Purinérgicos P1/metabolismo , Receptores Purinérgicos P2/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Cytometry A ; 87(11): 989-1000, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26243460

RESUMO

The kinins bradykinin and des-arg(9) -bradykinin cleaved from kininogen precursors by kallikreins exert their biological actions by stimulating kinin-B2 and B1 receptors, respectively. In vitro models of neural differentiation such as P19 embryonal carcinoma cells and neural progenitor cells have suggested the involvement of B2 receptors in neural differentiation and phenotype determination; however, the involvement of B1 receptors in these processes has not been established. Here, we show that B1 and B2 receptors are differentially expressed in mouse embryonic E14Tg2A stem cells undergoing neural differentiation. Proliferation and differentiation assays, performed in the presence of receptor subtype-selective agonists and antagonists, revealed that B1 receptor activity is required for the proliferation of embryonic and differentiating cells as well as for neuronal maturation at later stages of differentiation, while the B2 receptor acts on neural phenotype choice, promoting neurogenesis over gliogenesis. Besides the elucidation of bradykinin functions in an in vitro model reflecting early embryogenesis and neurogenesis, this study contributes to the understanding of B1 receptor functions in this process.


Assuntos
Bradicinina/metabolismo , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Neurais/citologia , Fenótipo , Receptores da Bradicinina/metabolismo , Animais , Camundongos , Neurônios/citologia
17.
Cytometry A ; 83(1): 48-61, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23027703

RESUMO

Modern medicine will unequivocally include regenerative medicine as a major breakthrough in the re-establishment of damaged or lost tissues due to degenerative diseases or injury. In this scenario, millions of patients worldwide can have their quality of life improved by stem cell implantation coupled with endogenous secretion or administration of survival and differentiation promoting factors. Large efforts, relying mostly on flow cytometry and imaging techniques, have been put into cell isolation, immunophenotyping, and studies of differentiation properties of stem cells of diverse origins. Mesenchymal stem cells (MSCs) are particularly relevant for therapy due to their simplicity of isolation. A minimal phenotypic pattern for the identification of MSCs cells requires them to be immunopositive for CD73, CD90, and CD105 expression, while being negative for CD34, CD45, and HLA-DR and other surface markers. MSCs identified by their cell surface marker expression pattern can be readily purified from patient's bone marrow and adipose tissues. Following expansion and/or predifferentiation into a desired tissue type, stem cells can be reimplanted for tissue repair in the same patient, virtually eliminating rejection problems. Transplantation of MSCs is subject of almost 200 clinical trials to cure and treat a very broad range of conditions, including bone, heart, and neurodegenerative diseases. Immediate or medium term improvements of clinical symptoms have been reported as results of many clinical studies.


Assuntos
Citometria de Fluxo/métodos , Imunofenotipagem/métodos , Células-Tronco Mesenquimais/citologia , Medicina Regenerativa/tendências , Diferenciação Celular , Proliferação de Células , Humanos
18.
Cell Commun Signal ; 11(1): 12, 2013 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-23414261

RESUMO

Purinergic receptors participate, in almost every cell type, in controlling metabolic activities and many physiological functions including signal transmission, proliferation and differentiation. While most of P2Y receptors induce transient elevations of intracellular calcium concentration by activation of intracellular calcium pools and forward these signals as waves which can also be transmitted into neighboring cells, P2X receptors produce calcium spikes which also include activation of voltage-operating calcium channels. P2Y and P2X receptors induce calcium transients that activate transcription factors responsible for the progress of differentiation through mediators including calmodulin and calcineurin. Expression of P2X2 as well as of P2X7 receptors increases in differentiating neurons and glial cells, respectively. Gene expression silencing assays indicate that these receptors are important for the progress of differentiation and neuronal or glial fate determination. Metabotropic receptors, mostly P2Y1 and P2Y2 subtypes, act on embryonic cells or cells at the neural progenitor stage by inducing proliferation as well as by regulation of neural differentiation through NFAT translocation. The scope of this review is to discuss the roles of purinergic receptor-induced calcium spike and wave activity and its codification in neurodevelopmental and neurodifferentiation processes.

19.
Front Neurosci ; 17: 1132825, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090809

RESUMO

Introduction: Physical exercise has beneficial effects by providing neuroprotective and anti-inflammatory responses to AD. Most studies, however, have been conducted with aerobic exercises, and few have investigated the effects of other modalities that also show positive effects on AD, such as resistance exercise (RE). In addition to its benefits in developing muscle strength, balance and muscular endurance favoring improvements in the quality of life of the elderly, RE reduces amyloid load and local inflammation, promotes memory and cognitive improvements, and protects the cortex and hippocampus from the degeneration that occurs in AD. Similar to AD patients, double-transgenic APPswe/PS1dE9 (APP/PS1) mice exhibit Αß plaques in the cortex and hippocampus, hyperlocomotion, memory deficits, and exacerbated inflammatory response. Therefore, the aim of this study was to investigate the effects of 4 weeks of RE intermittent training on the prevention and recovery from these AD-related neuropathological conditions in APP/PS1 mice. Methods: For this purpose, 6-7-month-old male APP/PS1 transgenic mice and their littermates, negative for the mutations (CTRL), were distributed into three groups: CTRL, APP/PS1, APP/PS1+RE. RE training lasted four weeks and, at the end of the program, the animals were tested in the open field test for locomotor activity and in the object recognition test for recognition memory evaluation. The brains were collected for immunohistochemical analysis of Aß plaques and microglia, and blood was collected for plasma corticosterone by ELISA assay. Results: APP/PS1 transgenic sedentary mice showed increased hippocampal Aß plaques and higher plasma corticosterone levels, as well as hyperlocomotion and reduced central crossings in the open field test, compared to APP/PS1 exercised and control animals. The intermittent program of RE was able to recover the behavioral, corticosterone and Aß alterations to the CTRL levels. In addition, the RE protocol increased the number of microglial cells in the hippocampus of APP/PS1 mice. Despite these alterations, no memory impairment was observed in APP/PS1 mice in the novel object recognition test. Discussion: Altogether, the present results suggest that RE plays a role in alleviating AD symptoms, and highlight the beneficial effects of RE training as a complementary treatment for AD.

20.
Stem Cell Rev Rep ; 19(6): 1800-1811, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37129730

RESUMO

Proteins involved in the Alzheimer's disease (AD), such as amyloid precursor protein (APP) and presenilin-1 (PS1), play critical roles in early development of the central nervous system (CNS), as well as in innate immune and glial cell responses. Familial AD is associated with the presence of APPswe and PS1dE9 mutations. However, it is still unknown whether these mutations cause deficits in CNS development of carriers. We studied genome-wide gene expression profiles of differentiated neural progenitor cells (NPCs) from wild-type and APPswe/PS1dE9 mouse embryo telencephalon. The occurrence of strong innate immune and glial cell responses in APPswe/PS1dE9 neurospheres mainly involves microglial activation, inflammatory mediators and chemokines. APPswe/PS1dE9 neurospheres augmented up to 100-fold CCL12, CCL5, CCL3, C3, CX3CR1, TLR2 and TNF-alpha expression levels, when compared to WT neurospheres. Expression levels of the glia cell marker GFAP and microglia marker Iba-1 were up to 20-fold upregulated in APPswe/PS1dE9 neurospheres. The secretome of differentiated APPswe/PS1dE9 NPCs revealed enhanced chemoattraction of peripheral blood mononuclear cells. When evaluating the inferred protein interaction networks constructed from the array data, an improvement in astrocyte differentiation in APPswe/PS1dE9 neurospheres was evident in view of increased GFAP expression. Transgenic NPCs differentiated into neural phenotypes presented expression patterns of cytokine, glial cells, and inflammatory mediators characteristic of APPswe/PS1dE9 adult animals. Consequently, the neurogenic niche obtained from differentiation of embryonic APPswe/PS1dE9 neurospheres spontaneously presents several alterations observed in adult AD brains. Finally, our data strengthen pathophysiological hypotheses that propose an early neurodevelopmental origin for familial AD.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Leucócitos Mononucleares/metabolismo , Camundongos Transgênicos , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Neuroglia/metabolismo , Diferenciação Celular/genética , Mediadores da Inflamação , Imunidade Inata/genética
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