Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Schizophr Res ; 270: 260-272, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38944972

RESUMO

BACKGROUND: It is known that the immune system is dysregulated in schizophrenia, having a state similar to chronic neuroinflammation. The origin of this process is unknown, but it is known that T and B lymphocytes, which are components of the adaptive immune system, play an important role in the pathogenic mechanisms of schizophrenia. METHODS: We analysed the membrane of PBMCs from patients diagnosed with schizophrenia through proteomic analysis (n = 5 schizophrenia and n = 5 control). We found the presence of the Kv1.3 voltage-gated potassium channel and its auxiliary subunit ß1 (KCNAB1) and ß2 (KCNAB2). From a sample of 90 participants, we carried out a study on lymphocytes with whole-cell patch-clamp experiments (n = 7 schizophrenia and n = 5 control), western blot (n = 40 schizophrenia and n = 40 control) and confocal microscopy to evaluate the presence and function of different channels. Kv in both cells. RESULTS: We demonstrated the overexpression of Kv1.1, Kv1.2, Kv1.3, Kv1.6, Kv4.2, Kv4.3 and Kv7.2 channels in PBMCs from patients with schizophrenia. This study represents a groundbreaking exploration, as it involves an electrophysiological analysis performed on T and B lymphocytes from patients diagnosed of schizophrenia compared to healthy participants. We observed that B lymphocytes exhibited an increase in output current along with greater peak current amplitude and voltage conductance curves among patients with schizophrenia compared with healthy controls. CONCLUSIONS: This study showed the importance of the B lymphocyte in schizophrenia. We know that the immune system is altered in schizophrenia, but the physiological mechanisms of this system are not very well known. We suggest that the B lymphocyte may be relevant in the pathophysiology of schizophrenia and that it should be investigated in more depth, opening a new field of knowledge and possibilities for new treatments combining antipsychotics and immunomodulators. The limitation is that all participants received antipsychotic medication, which may have influenced the differences observed between patients and controls. This implies that more studies need to be done where the groups can be separated according to the antipsychotic drug.

2.
J Cell Biol ; 221(11)2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36121394

RESUMO

Phagocytosis requires actin dynamics, but whether actomyosin contractility plays a role in this morphodynamic process is unclear. Here, we show that in the retinal pigment epithelium (RPE), particle binding to Mer Tyrosine Kinase (MerTK), a widely expressed phagocytic receptor, stimulates phosphorylation of the Cdc42 GEF Dbl3, triggering activation of MRCKß/myosin-II and its coeffector N-WASP, membrane deformation, and cup formation. Continued MRCKß/myosin-II activity then drives recruitment of a mechanosensing bridge, enabling cytoskeletal force transmission, cup closure, and particle internalization. In vivo, MRCKß is essential for RPE phagocytosis and retinal integrity. MerTK-independent activation of MRCKß signaling by a phosphomimetic Dbl3 mutant rescues phagocytosis in retinitis pigmentosa RPE cells lacking functional MerTK. MRCKß is also required for efficient particle translocation from the cortex into the cell body in Fc receptor-mediated phagocytosis. Thus, conserved MRCKß signaling at the cortex controls spatiotemporal regulation of actomyosin contractility to guide distinct phases of phagocytosis in the RPE and represents the principle phagocytic effector pathway downstream of MerTK.


Assuntos
Actomiosina , Miotonina Proteína Quinase , Fagocitose , Actinas/metabolismo , Actomiosina/metabolismo , Miosina Tipo II/metabolismo , Miotonina Proteína Quinase/metabolismo , Fagocitose/fisiologia , Proteínas Tirosina Quinases , Receptores Fc , c-Mer Tirosina Quinase/metabolismo
3.
Pharmaceutics ; 14(2)2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35214137

RESUMO

The major limitation of any cancer therapy lies in the difficulty of precisely controlling the localization of the drug in the tumor cells. To improve this drawback, our study explores the use of actively-targeted chemo-photo-nanocarriers that recognize and bind to epidermal growth factor receptor-overexpressing cells and promote the local on-demand release of the chemotherapeutic agent doxorubicin triggered by light. Our results show that the attachment of high concentrations of doxorubicin to cetuximab-IRDye700DX-mesoporous silica nanoparticles yields efficient and selective photokilling of EGFR-expressing cells mainly through singlet oxygen-induced release of the doxorubicin from the nanocarrier and without any dark toxicity. Therefore, this novel triply functionalized nanosystem is an effective and safe nanodevice for light-triggered on-demand doxorubicin release.

4.
Cell Mol Neurobiol ; 42(6): 1921-1932, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33712885

RESUMO

The brain extracellular matrix (ECM) is involved in crucial processes of neural support, neuronal and synaptic plasticity, extrasynaptic transmission, and neurotransmission. ECM is a tridimensional fibrillary meshwork composed of macromolecules that determine its bioactivity and give it unique characteristics. The characterization of the brain ECM is critical to understand its dynamic in SZ. Thus, a comparative study was developed with 71 patients with schizophrenia (SZ) and 70 healthy controls. Plasma of participants was analysed by label-free liquid chromatography-tandem mass spectrometry, and the results were validated using the classical western blot method. Lastly, immunostaining of post-mortem human brain tissue was performed to analyse the distribution of the brain ECM proteins by confocal microscopy. The analysis identified four proteins: fibronectin, lumican, nidogen-1, and secreted protein acidic and rich in cysteine (SPARC) as components of the brain ECM. Statistical significance was found for fibronectin (P = 0.0166), SPARC (P = 0.0003), lumican (P = 0.0012), and nidogen-1 (P < 0.0001) that were decreased in the SZ group. Fluorescence imaging of prefrontal cortex (PFC) sections revealed a lower expression of ECM proteins in SZ. Our study proposes a pathophysiological dysregulation of proteins of the brain ECM, whose abnormal composition leads to a progressive neuronal impairment and consequently to neurodegenerative processes due to lack of neurophysiological support and dysregulation of neuronal homeostasis. Moreover, the brain ECM and its components are potential pharmacological targets to develop new therapeutic approaches to treat SZ.


Assuntos
Fibronectinas , Esquizofrenia , Encéfalo/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Humanos , Lumicana/metabolismo , Osteonectina/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo
5.
Rev Psiquiatr Salud Ment (Engl Ed) ; 14(3): 125-138, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34384726

RESUMO

INTRODUCTION: Schizophrenia is a chronic illness often accompanied by metabolic disorders, diabetes, obesity and cardiovascular problems often associated with unhealthy lifestyles, as well as neuroendocrine problems caused by the disease itself. Lifestyle changes, such as regular physical exercise, have a positive effect on metabolic disorders and mental health, although the molecular changes that occur in this type of patient and how they explain the changes in their response are unknown. This study wants to analyze in a novel way the proteins and molecular pathways involved in critical plasmatic proteins in plasma to reveal the pathways involved in the implementation of physical exercise and the changes that occur among patients who participate in such programs with those who leave. METHODS: Twenty-one patients with chronic schizophrenia underwent a daily, 6-month aerobic training program. We divided them into a group that completed the program (12 patients) and a second group that left the training program (9 patients). The biochemical and clinical data of each patient were analyzed and the proteomic profile of the plasma was studied using ESI-LC-MS/MS. RESULTS: Proteomic analysis recognizes 21.165 proteins and peptides in each patient, of which we identified 1.812 proteins that varied between both groups linked to the metabolic and biological regulation pathways. After clinical analysis of each patient we found significant differences in weight, BMI, abdominal perimeter, diastolic blood pressure, and HDL cholesterol levels. The main change that vertebrates both groups is the Self-Assessment Anhedonia Scale, where we detected higher levels in the dropout group (no physical activity) compared to the active group. CONCLUSION: The benefits of physical exercise are clear in chronic patients with schizophrenia, as it substantially improves their BMI, as well as their clinical and biochemical parameters. However, our study reveals the biological and molecular pathways that affect physical exercise in schizophrenia, such as important metabolic proteins such as ApoE and ApoC, proteins involved in neuronal regulation such as tenascin and neurotrophins, neuroinflammatory regulatory pathways such as lipocalin-2 and protein 14-3-3, as well as cytoskeleton proteins of cells such as spectrins and annexines. Understanding these molecular mechanisms opens the door to future therapies in the chronicity of schizophrenia.


Assuntos
Esquizofrenia , Animais , Cromatografia Líquida , Exercício Físico , Humanos , Projetos Piloto , Proteômica , Espectrometria de Massas em Tandem
6.
Int J Mol Sci ; 22(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34445205

RESUMO

The neurobiology of schizophrenia is multifactorial, comprising the dysregulation of several biochemical pathways and molecules. This research proposes a peripheral biomarker for schizophrenia that involves the second extracellular loop of norepinephrine transporter (NEText), the tropomyosin receptor kinase C (TrkC), and the neurotrophin-3 (NT-3) in T cells. The study of NEText, NT-3, and TrkC was performed in T cells and plasma extracted from peripheral blood of 54 patients with schizophrenia and 54 healthy controls. Levels of NT-3, TrkC, and NET were significantly lower in plasma and T cells of patients compared to healthy controls. Co-immunoprecipitation (co-IPs) showed protein interactions with Co-IP NEText-NT-3 and Co-IP NEText-TrkC. Computational modelling of protein-peptide docking by CABS-dock provided a medium-high accuracy model for NT-3-NEText (4.6935 Å) and TrkC-NEText (2.1365 Å). In summary, immunocomplexes reached statistical relevance in the T cells of the control group contrary to the results obtained with schizophrenia. The reduced expression of NT-3, TrkC, and NET, and the lack of molecular complexes in T cells of patients with schizophrenia may lead to a peripheral dysregulation of intracellular signaling pathways and an abnormal reuptake of norepinephrine (NE) by NET. This peripheral molecular biomarker underlying schizophrenia reinforces the role of neurotrophins, and noradrenergic and immune systems in the pathophysiology of schizophrenia.


Assuntos
Simulação de Acoplamento Molecular , Neurotrofina 3/química , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/química , Receptor trkC/química , Esquizofrenia/etiologia , Adulto , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurotrofina 3/genética , Neurotrofina 3/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Estrutura Secundária de Proteína , Receptor trkC/genética , Receptor trkC/metabolismo , Esquizofrenia/genética , Esquizofrenia/metabolismo
7.
J Pediatr ; 232: 287-289.e4, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33484697

RESUMO

We conducted a multicenter clinical validity study of the Panbio coronavirus disease 2019 Antigen Rapid Test of nasopharyngeal samples in pediatric patients with coronavirus disease 2019-compatible symptoms of ≤5 days of evolution. Our study showed limited accuracy in nasopharyngeal antigen testing: overall sensitivity was 45.4%, and 99.8% of specificity, positive-predictive value was 92.5%.


Assuntos
Antígenos Virais/análise , COVID-19/diagnóstico , DNA Viral/análise , Nasofaringe/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/genética , Adolescente , COVID-19/virologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pandemias , Reprodutibilidade dos Testes , SARS-CoV-2/imunologia
8.
Chemistry ; 27(15): 4955-4963, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33442909

RESUMO

Herein, the photodynamic activity of phthalocyanine (pc)-assembled nanoparticles against bacterial strains is demonstrated. The photosensitizers (PS) studied in this work are two chiral ZnII Pcs (PS-1 and PS-2), with an AABB geometry (where A and B refer to differently substituted isoindole constituents). They contain differently functionalized, chiral binaphthyloxy-linked A isoindole units, which determine the hydrophobicity of the system, and cationic methyl pyridinium moieties in the other two isoindoles to embody hydrophilicity. Both compounds have the ability to self-assemble into nanoparticles in aqueous media and have proved efficient in the photo-inactivation of Staphylococcus aureus and Escherichia coli, selected as models of Gram-positive and Gram-negative bacteria. The average size of the nanoparticles was determined by substitution at the binaphthyl core and, in turn, influences the toxicity of the PS. Thus, PS-1, presenting a nonsubstituted binaphthyl core, forms larger nanoparticles with a larger cationic surface than the octyl-functionalized PS-2. Although both PSs present similar structure and photophysical features, the self-assembled nanostructures of PS-1 are more effective at killing both types of strain, showing an outstanding photo-inactivation capacity with the Gram-negative E. coli.


Assuntos
Anti-Infecciosos , Nanoestruturas , Fotoquimioterapia , Antibacterianos/farmacologia , Escherichia coli , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Indóis , Isoindóis , Fármacos Fotossensibilizantes
9.
Sci Rep ; 10(1): 14271, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868793

RESUMO

Schizophrenia is a progressive disorder characterized by multiple psychotic relapses. After every relapse, patients may not fully recover, and this may lead to a progressive loss of functionality. Pharmacological treatment represents a key factor to minimize the biological, psychological and psychosocial impact of the disorder. The number of relapses and the duration of psychotic episodes induce a potential neuronal damage and subsequently, neurodegenerative processes. Thus, a comparative study was performed, including forty healthy controls and forty-two SZ patients divided into first-episode psychosis (FEP) and chronic SZ (CSZ) subgroups, where the CSZ sub group was subdivided by antipsychotic treatment. In order to measure the potential neuronal damage, plasma levels of ß-III tubulin, neurofilament light chain (Nf-L), and glial fibrillary acidic protein (GFAP) were performed. The results revealed that the levels of these proteins were increased in the SZ group compared to the control group (P < 0.05). Moreover, multiple comparison analysis showed highly significant levels of ß-III tubulin (P = 0.0002), Nf-L (P = 0.0403) and GFAP (P < 0.015) in the subgroup of CSZ clozapine-treated. In conclusion, ß-III tubulin, Nf-L and GFAP proteins may be potential biomarkers of neurodegeneration and progression in SZ.


Assuntos
Encéfalo/patologia , Proteína Glial Fibrilar Ácida/sangue , Proteínas de Neurofilamentos/sangue , Esquizofrenia/patologia , Tubulina (Proteína)/sangue , Adulto , Antipsicóticos/uso terapêutico , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Esquizofrenia/sangue , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo
10.
Photochem Photobiol ; 96(3): 570-580, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32104926

RESUMO

Active targeting strategies are currently being extensively investigated in order to enhance the selectivity of photodynamic therapy. The aim of the present research was to evaluate whether the external decoration of nanopolymeric carriers with targeting peptides could add more value to a photosensitizer formulation and increase antitumor therapeutic efficacy and selectivity. To this end, we assessed PLGA-PLA-PEG nanoparticles (NPs) covalently attached to a hydrophilic photosensitizer 5-[4-azidophenyl]-10,15,20-tri-(N-methyl-4-pyridinium)porphyrinato zinc (II) trichloride (ZnTriMPyP) and also to c(RGDfK) peptides, in order to target αv ß3 integrin-expressing cells. In vitro phototoxicity investigations showed that the ZnTriMPyP-PLGA-PLA-PEG-c(RGDfK) nanosystem is effective at submicromolar concentrations, is devoid of dark toxicity, successfully targets αv ß3 integrin-expressing cells and is 10-fold more potent than related nanosystems where the PS is occluded instead of covalently bound.


Assuntos
Portadores de Fármacos , Nanopartículas , Neoplasias/tratamento farmacológico , Oligopeptídeos/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Polímeros/química , Linhagem Celular Tumoral , Humanos , Integrinas/efeitos dos fármacos , Cinética , Fármacos Fotossensibilizantes/uso terapêutico , Oxigênio Singlete/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
11.
Clin EEG Neurosci ; 51(1): 3-9, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31537100

RESUMO

Major depressive disorder (MDD) is a multidimensional disorder that is characterized by the presence of alterations in mood, cognitive capacity, sensorimotor, and homeostatic functions. Given that about half of the patients diagnosed with MDD do not respond to the various current treatments, new techniques are being sought to predict not only the course of the disease but also the characteristics that differentiate responders from non-responders. Using the electroencephalogram, a noninvasive and inexpensive tool, most studies have proposed that patients with MDD have some lateralization in brain electrical activity, with alterations in alpha and theta rhythms being observed, which would be related to dysfunctions in emotional capacity such as the absence or presence of responses to the different existing treatments. These alterations help in the identification of subjects at high risk of suffering from depression, in the differentiation into responders and nonresponders to various therapies (pharmacological, electroconvulsive therapy, and so on), as well as to establish in which period of the disease the treatment will be more effective. Although the data are still inconclusive and more research is needed, these alpha and theta neurophysiological markers could support future clinical practice when it comes to establishing an early diagnosis and treating state disorders more successfully and accurately of mood disorders.


Assuntos
Ondas Encefálicas/fisiologia , Depressão/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Ritmo Teta/fisiologia , Afeto/fisiologia , Animais , Biomarcadores/análise , Humanos
12.
Enferm Clin (Engl Ed) ; 30(5): 295-301, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31732428

RESUMO

AIMS: To analyze the incidence of complications related to the central peripheral insertion catheter and the viability of the infusion of haematopoietic stem cells through volumetric perfusion pumps. METHOD: Prospective descriptive study that includes all patients who received a haematopoietic transplant in the Haematology Service of the Hospital Clínico de Valencia between January and December 2016 (n=73). All of them received a central peripheral insertion catheter. SPSS™ v22 was used to perform the descriptive analysis of the main variables using a confidence interval of 95%. The student's t-test was used to compare the means of two independent samples assuming unequal variances. RESULTS: The 63% (n=73) of the catheters remained without problems throughout the procedure. Fever of unknown origin (28.8%) was the main cause of catheter removal. The median number of days for haematological recovery was 12.5 for the autologous transplants and 15 for the allogeneic transplants. CONCLUSIONS: The central peripheral insertion catheter presents few complications related to insertion. The administration of haematopoietic cells through these catheters with volumetric perfusion pumps does not imply a delay in haematological recovery. Good acceptance by the patient is confirmed.


Assuntos
Cateterismo Venoso Central , Cateterismo Periférico , Cateteres Venosos Centrais , Transplante de Células-Tronco Hematopoéticas , Cateterismo Venoso Central/efeitos adversos , Catéteres , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Estudos Prospectivos
13.
Front Psychiatry ; 10: 885, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849731

RESUMO

Schizophrenia is a severe and disabling psychiatric disorder with a complex and multifactorial etiology. The lack of consensus regarding the multifaceted dysfunction of this ailment has increased the need to explore new research lines. This research makes use of proteomics data to discover possible analytes associated with psychoneuroimmune signaling pathways in schizophrenia. Thus, we analyze plasma of 45 patients [10 patients with first-episode schizophrenia (FES) and 35 patients with chronic schizophrenia] and 43 healthy subjects by label-free liquid chromatography-tandem mass spectrometry. The analysis revealed a significant reduction in the levels of glia maturation factor beta (GMF-ß), the brain-derived neurotrophic factor (BDNF), and the 115-kDa isoform of the Rab3 GTPase-activating protein catalytic subunit (RAB3GAP1) in patients with schizophrenia as compared to healthy volunteers. In conclusion, GMF-ß, BDNF, and 115-kDa isoform of RAB3GAP1 showed significantly reduced levels in plasma of patients with schizophrenia, thus making them potential biomarkers in schizophrenia.

15.
Sci Rep ; 8(1): 1204, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29352236

RESUMO

Tight junctions are required for the formation of tissue barriers and function as suppressors of signalling mechanisms that control gene expression and cell behaviour; however, little is known about the physiological and developmental importance of such signalling functions. Here, we demonstrate that depletion of MarvelD3, a transmembrane protein of tight junctions, disrupts neural crest formation and, consequently, development of neural crest-derived tissues during Xenopus embryogenesis. Using embryos and explant cultures combined with a small molecule inhibitor or mutant mRNAs, we show that MarvelD3 is required to attenuate JNK signalling during neural crest induction and that inhibition of JNK pathway activation is sufficient to rescue the phenotype induced by MarvelD3 depletion. Direct JNK stimulation disrupts neural crest development, supporting the importance of negative regulation of JNK. Our data identify the junctional protein MarvelD3 as an essential regulator of early vertebrate development and neural crest induction and, thereby, link tight junctions to the control and timing of JNK signalling during early development.


Assuntos
Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Sistema de Sinalização das MAP Quinases , Proteínas com Domínio MARVEL/genética , Crista Neural/embriologia , Crista Neural/metabolismo , Animais , Biomarcadores , Diferenciação Celular/genética , Ectoderma/embriologia , Ectoderma/metabolismo , Embrião não Mamífero , Desenvolvimento Embrionário/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas com Domínio MARVEL/metabolismo , Fenótipo , Xenopus
16.
Front Pediatr ; 5: 288, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29318135

RESUMO

The objective is to evaluate the sleep characteristics of the staff working in a pediatric intensive care unit (PICU). They were asked to complete an anonymous survey concerning the characteristics and quality of their sleep, as well as the impact of sleep disturbances on their work and social life, assessed by Functional Outcomes of Sleep Questionnaire (FOSQ)-10 questionnaire. The response rate was 84.6% (85% females): 17% were doctors, 57% nurses, 23% nursing assistants, and 3% porters. 83.8% of them worked on fix shifts and 16.2% did 24-h shifts. 39.8% of workers considered that they had a good sleep quality and 39.8% considered it to be poor or bad. The score was good in 18.2% of the staff and bad in 81.8%. Night shift workers showed significantly worse sleep quality on both the objective and subjective evaluation. There was a weak concordance (kappa 0.267; p = 0.004) between the perceived quality of sleep and the FOSQ-10 evaluation. Sleep disorders affected their emotional state (30.2% of workers) and relationships or social life (22.6%). In conclusion, this study finds that a high percentage of health professionals from PICU suffer from sleep disorders that affect their personal and social life. This negative impact is significantly higher in night shift workers. Many health workers are not aware of their bad sleep quality.

17.
Biol Open ; 5(11): 1631-1641, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27870636

RESUMO

Ocular morphogenesis requires several signalling pathways controlling the expression of transcription factors and cell-cycle regulators. However, despite a well-known mechanism, the dialogue between those signals and factors remains to be unveiled. Here, we identify a requirement for MarvelD3, a tight junction transmembrane protein, in eye morphogenesis in Xenopus MarvelD3 depletion led to an abnormally pigmented eye or even an eye-less phenotype, which was rescued by ectopic MarvelD3 expression. Altering MarvelD3 expression led to deregulated expression of cell-cycle regulators and transcription factors required for eye development. The eye phenotype was rescued by increased c-Jun terminal Kinase activation. Thus, MarvelD3 links tight junctions and modulation of the JNK pathway to eye morphogenesis.

18.
Dev Cell ; 37(5): 473-83, 2016 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-27270042

RESUMO

Membrane contact sites between the ER and multivesicular endosomes/bodies (MVBs) play important roles in endosome positioning and fission and in neurite outgrowth. ER-MVB contacts additionally function in epidermal growth factor receptor (EGFR) tyrosine kinase downregulation by providing sites where the ER-localized phosphatase, PTP1B, interacts with endocytosed EGFR before the receptor is sorted onto intraluminal vesicles (ILVs). Here we show that these contacts are tethered by annexin A1 and its Ca(2+)-dependent ligand, S100A11, and form a subpopulation of differentially regulated contact sites between the ER and endocytic organelles. Annexin A1-regulated contacts function in the transfer of ER-derived cholesterol to the MVB when low-density lipoprotein-cholesterol in endosomes is low. This sterol traffic depends on interaction between ER-localized VAP and endosomal oxysterol-binding protein ORP1L, and is required for the formation of ILVs within the MVB and thus for the spatial regulation of EGFR signaling.


Assuntos
Anexina A1/metabolismo , Colesterol/metabolismo , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Transporte Biológico/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/ultraestrutura , Endossomos/efeitos dos fármacos , Endossomos/ultraestrutura , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Células HeLa , Humanos , Lipoproteínas LDL/farmacologia , Corpos Multivesiculares/efeitos dos fármacos , Corpos Multivesiculares/metabolismo , Corpos Multivesiculares/ultraestrutura , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Receptores de Esteroides/metabolismo , Vesículas Transportadoras/efeitos dos fármacos , Vesículas Transportadoras/metabolismo , Proteínas de Transporte Vesicular/metabolismo
20.
PLoS One ; 6(8): e24044, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21901156

RESUMO

Mutations in the inositol polyphosphate 5-phosphatase OCRL1 cause Lowe Syndrome, leading to cataracts, mental retardation and renal failure. We noted that cell types affected in Lowe Syndrome are highly polarized, and therefore we studied OCRL1 in epithelial cells as they mature from isolated individual cells into polarized sheets and cysts with extensive communication between neighbouring cells. We show that a proportion of OCRL1 targets intercellular junctions at the early stages of their formation, co-localizing both with adherens junctional components and with tight junctional components. Correlating with this distribution, OCRL1 forms complexes with junctional components α-catenin and zonula occludens (ZO)-1/2/3. Depletion of OCRL1 in epithelial cells growing as a sheet inhibits maturation; cells remain flat, fail to polarize apical markers and also show reduced proliferation. The effect on shape is reverted by re-expressed OCRL1 and requires the 5'-phosphatase domain, indicating that down-regulation of 5-phosphorylated inositides is necessary for epithelial development. The effect of OCRL1 in epithelial maturation is seen more strongly in 3-dimensional cultures, where epithelial cells lacking OCRL1 not only fail to form a central lumen, but also do not have the correct intracellular distribution of ZO-1, suggesting that OCRL1 functions early in the maturation of intercellular junctions when cells grow as cysts. A role of OCRL1 in junctions of polarized cells may explain the pattern of organs affected in Lowe Syndrome.


Assuntos
Polaridade Celular/fisiologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Síndrome Oculocerebrorrenal/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Animais , Western Blotting , Células CACO-2 , Proteínas de Transporte/metabolismo , Linhagem Celular , Polaridade Celular/genética , Proliferação de Células , Forma Celular/genética , Forma Celular/fisiologia , Cães , Eletroforese em Gel de Poliacrilamida , Humanos , Imunoprecipitação , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Síndrome Oculocerebrorrenal/genética , Fosfoproteínas/metabolismo , Monoéster Fosfórico Hidrolases/genética , Interferência de RNA , Proteínas da Zônula de Oclusão , Proteína da Zônula de Oclusão-1 , Proteína da Zônula de Oclusão-2 , alfa Catenina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA