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1.
Science ; 368(6495): 1132-1135, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32499443

RESUMO

The lumicrine system is a postulated signaling system in which testis-derived (upstream) secreted factors enter the male reproductive tract to regulate epididymal (downstream) pathways required for sperm maturation. Until now, no lumicrine factors have been identified. We demonstrate that a testicular germ-cell-secreted epidermal growth factor-like protein, neural epidermal growth factor-like-like 2 (NELL2), specifically binds to an orphan receptor tyrosine kinase, c-ros oncogene 1 (ROS1), and mediates the differentiation of the initial segment (IS) of the caput epididymis. Male mice in which Nell2 had been knocked out were infertile. The IS-specific secreted proteases, ovochymase 2 (OVCH2) and A disintegrin and metallopeptidase 28 (ADAM28), were expressed upon IS maturation, and OVCH2 was required for processing of the sperm surface protein ADAM3, which is required for sperm fertilizing ability. This work identifies a lumicrine system essential for testis-epididymis-spermatozoa (NELL2-ROS1-OVCH2-ADAM3) signaling and male fertility.


Assuntos
Comunicação Celular/fisiologia , Endopeptidases/metabolismo , Epididimo/metabolismo , Fertilidade , Infertilidade Masculina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Proteínas ADAM/metabolismo , Animais , Comunicação Celular/genética , Endopeptidases/genética , Infertilidade Masculina/genética , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo
2.
Tumori ; 106(4): 325-332, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32567505

RESUMO

INTRODUCTION: In January 2020, the coronavirus disease 2019 (COVID-19) outbreak in Italy necessitated rigorous application of more restrictive safety procedures in the management and treatment of patients with cancer to ensure patient and staff protection. Identification of respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was a challenge during the pandemic owing to a large number of asymptomatic or mildly symptomatic patients. METHODS: We report 5 patients with unknown SARS-CoV-2 infection undergoing positron emission tomography (PET)/computed tomography (CT) with radiopharmaceuticals targeting different tumor processes: 18F-FDG, 18F-choline (FCH), and 68Ga-PSMA. RESULTS: In all patients, PET/CT showed increased tracer uptake in the lungs corresponding to CT findings of SARS-CoV-2 pneumonia. Quantitative assessment of tracer uptake showed more elevated values for the glucose analogue 18F-FDG (mean SUVmax 5.4) than for the other tracers (mean SUVmax 3.5). CONCLUSIONS: Our findings suggest that PET/CT is a sensitive modality to hypothesize SARS-CoV-2 pneumonia in patients with cancer, even when asymptomatic. More data are needed to verify the correlation among immune response to SARS-CoV-2 infection, clinical evolution, and PET results. Under the strict safety measures implemented at the PET center, the number of potentially SARS-CoV-2-positive patients undergoing PET/CT was very low (1.6%), and no staff member has been diagnosed with infection as of April 30, 2020.


Assuntos
Infecções por Coronavirus/diagnóstico , Neoplasias/diagnóstico , Pneumonia Viral/diagnóstico , Pneumonia/diagnóstico , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Betacoronavirus/patogenicidade , Meios de Contraste/uso terapêutico , Infecções por Coronavirus/complicações , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Surtos de Doenças , Feminino , Fluordesoxiglucose F18/uso terapêutico , Humanos , Itália/epidemiologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Glicoproteínas de Membrana/uso terapêutico , Neoplasias/complicações , Neoplasias/terapia , Neoplasias/virologia , Compostos Organometálicos/uso terapêutico , Pandemias , Pneumonia/complicações , Pneumonia/terapia , Pneumonia/virologia , Pneumonia Viral/complicações , Pneumonia Viral/terapia , Pneumonia Viral/virologia , Compostos Radiofarmacêuticos/uso terapêutico
3.
J Transl Med ; 18(1): 233, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32522207

RESUMO

BACKGROUND: Epidemiological, virological and pathogenetic characteristics of SARS-CoV-2 infection are under evaluation. A better understanding of the pathophysiology associated with COVID-19 is crucial to improve treatment modalities and to develop effective prevention strategies. Transcriptomic and proteomic data on the host response against SARS-CoV-2 still have anecdotic character; currently available data from other coronavirus infections are therefore a key source of information. METHODS: We investigated selected molecular aspects of three human coronavirus (HCoV) infections, namely SARS-CoV, MERS-CoV and HCoV-229E, through a network based-approach. A functional analysis of HCoV-host interactome was carried out in order to provide a theoretic host-pathogen interaction model for HCoV infections and in order to translate the results in prediction for SARS-CoV-2 pathogenesis. The 3D model of S-glycoprotein of SARS-CoV-2 was compared to the structure of the corresponding SARS-CoV, HCoV-229E and MERS-CoV S-glycoprotein. SARS-CoV, MERS-CoV, HCoV-229E and the host interactome were inferred through published protein-protein interactions (PPI) as well as gene co-expression, triggered by HCoV S-glycoprotein in host cells. RESULTS: Although the amino acid sequences of the S-glycoprotein were found to be different between the various HCoV, the structures showed high similarity, but the best 3D structural overlap shared by SARS-CoV and SARS-CoV-2, consistent with the shared ACE2 predicted receptor. The host interactome, linked to the S-glycoprotein of SARS-CoV and MERS-CoV, mainly highlighted innate immunity pathway components, such as Toll Like receptors, cytokines and chemokines. CONCLUSIONS: In this paper, we developed a network-based model with the aim to define molecular aspects of pathogenic phenotypes in HCoV infections. The resulting pattern may facilitate the process of structure-guided pharmaceutical and diagnostic research with the prospect to identify potential new biological targets.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno , Modelos Biológicos , Pneumonia Viral/genética , Pneumonia Viral/virologia , Mapeamento de Interação de Proteínas , Humanos , Glicoproteínas de Membrana/metabolismo , Pandemias , Transdução de Sinais/genética , Proteínas do Envelope Viral
4.
Science ; 368(6497)2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32554568

RESUMO

Meissner corpuscles are mechanosensory end organs that densely occupy mammalian glabrous skin. We generated mice that selectively lacked Meissner corpuscles and found them to be deficient in both perceiving the gentlest detectable forces acting on glabrous skin and fine sensorimotor control. We found that Meissner corpuscles are innervated by two mechanoreceptor subtypes that exhibit distinct responses to tactile stimuli. The anatomical receptive fields of these two mechanoreceptor subtypes homotypically tile glabrous skin in a manner that is offset with respect to one another. Electron microscopic analysis of the two Meissner afferents within the corpuscle supports a model in which the extent of lamellar cell wrappings of mechanoreceptor endings determines their force sensitivity thresholds and kinetic properties.


Assuntos
Epiderme/inervação , Células de Merkel/fisiologia , Células de Merkel/ultraestrutura , Percepção do Tato/fisiologia , Tato/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Feminino , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica , Proteínas Tirosina Quinases/genética , Transdução de Sinais
5.
Am J Clin Nutr ; 111(6): 1150-1158, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32393980

RESUMO

BACKGROUND: Saturated-fat intake and endotoxemia can impair cognition. However, their acute impact on cognitive performance is unknown. OBJECTIVE: This study assessed the impact of 2 high-fat meals and endotoxemia on attention. METHODS: In this double-blind, randomized crossover trial, 51 women (n = 32 breast cancer survivors, n = 19 noncancer controls; mean ± SD age: 53 ± 8 y) completed the Continuous Performance Test (CPT) and had their blood drawn to assess endotoxemia markers LPS binding protein (LBP), soluble CD14 (sCD14), and the LBP to sCD14 ratio 1 h prior to eating either a high-saturated-fat meal or a high-oleic-sunflower-oil meal. Women again completed the CPT 5 h postmeal. At 1 to 4 wk later, women completed the same protocol but consumed the other meal. RESULTS: In adjusted models, women had more difficulty distinguishing target stimuli from distractors after consuming the high-saturated-fat meal than they did after the oleic-sunflower-oil meal (B = 4.44, SE = 1.88, P = 0.02). Women with higher baseline LBP had less consistent response times (B = 0.002, SE = 0.0008, P = 0.04). Those with higher LBP and LBP:sCD14 were less able to sustain their attention throughout the entire CPT, as reflected by their progressively slower (B = 0.002, SE = 0.0006, P = 0.003; and B = 2.43, SE = 0.090, P = 0.008, respectively) and more erratic (B = 0.003, SE = 0.0008, P < 0.0001; and B = 3.29, SE = 1.17, P = 0.006, respectively) response times. Additionally, women with higher baseline LBP or sCD14 were less able to maintain or increase response speeds at higher interstimulus intervals (B = 0.002, SE = 0.0006, P = 0.02; and B = 0.006, SE = 0.003, P = 0.03, respectively), indicating greater difficulty adapting to changing task demands. Significant meal type by LBP and LBP:sCD14 interactions emerged (P < 0.05), such that high LBP and LBP:sCD14 erased between-meal cognitive differences, uniformly impairing performance. CONCLUSIONS: These results suggest that higher LBP, sCD14, and LBP:sCD14 and saturated-fat intake individually and jointly influence attention. Endotoxemia may override the relative cognitive benefit of healthier oil choices.This trial is registered at clinicaltrials.gov as NCT04247763.


Assuntos
Endotoxemia/psicologia , Proteínas da Fase Aguda , Adulto , Idoso , Atenção , Proteínas de Transporte/sangue , Cognição , Dieta Hiperlipídica/psicologia , Método Duplo-Cego , Endotoxemia/sangue , Endotoxemia/metabolismo , Feminino , Humanos , Receptores de Lipopolissacarídeos/sangue , Masculino , Refeições/psicologia , Glicoproteínas de Membrana/sangue , Pessoa de Meia-Idade , Período Pós-Prandial
6.
Medicine (Baltimore) ; 99(19): e19957, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32384443

RESUMO

Studies of PDPN in cancers have focused on the interactions with palates through the binding with CECL-2 which mainly express on palates and immune cells, while little is known on its interactions with immune cells.PDPN expression in cancers was analyzed through Oncomine, GEPIA, and TIMER database. Prognostic value (HR, P value from log-rank test) was evaluated through Kaplan-Meier plotter and OncoLnc database. The correlations between PDPN and the infiltrating levels of immune cells in different cancers, and diverse immune markers in gastric cancer were investigated through TIMER database.High PDPN expression predicted poor overall survival (OS) and post-progression survival (PPS) particularly in gastric cancer (OS P = .0089; PPS P = .00085), especially among patients with Her-2 (+) and lymph node metastasis. In addition, PDPN was positively correlated with infiltrating levels of immune cells, other than B cells in gastric cancer. However, PDPN showed more correlations with immune markers of M2 type TAM (CD163, VSIG4, MS4A4A) and T cell exhaustion (TIM-3, TOX, and GZMB).These findings all suggest that high PDPN predicts poor survival outcomes, especially for Her-2 (+) gastric cancer patients. Though inducing M2 type TAM and T cell exhaustion, high PDPN can predict high levels of various immune cells infiltration in STAD. Those correlations may bring new ideas to immunology treatment for gastric cancer patients who do not benefit from the existing immune checkpoint inhibitors.


Assuntos
Linfócitos do Interstício Tumoral/metabolismo , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/imunologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática/genética , Masculino , Prognóstico , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/mortalidade
7.
Life Sci ; 255: 117758, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32407845

RESUMO

AIMS: NLR family pyrin domain containing 3 (NLRP3) inflammasome activation contributes to the development of diabetic cardiovascular complications. CD38 regulates vascular inflammation through cyclic ADP-ribose (cADPR)-mediated Ca2+ signaling in vascular smooth muscle cells (VSMCs). Ca2+ mobilization may modulate inflammasome activation by impacting mitochondrial function. However, it remains unclear whether CD38 regulates NLRP3 inflammasome activation in VSMCs through cADPR-dependent Ca2+ release under diabetic condition. Main methods and key findings: In VSMCs, we observed that high glucose (HG, 30 mM) enhanced CD38 protein expression and ADP ribosyl cyclase activity. Moreover, along with less abundance of NLRP3, apoptosis-associated speck-like protein containing CARD (ASC) and their colocalization, the expression of active caspase-1(p20) and IL-1ß were significantly inhibited by CD38 gene deficiency with siRNA transfection in VSMCs. Further, CD38 regulated the release of intracellular cADPR-mediated Ca2+ and mitochondrial DNA (mtDNA) to the cytosol, which was associated with NLRP3 inflammasome activation and VSMCs proliferation and collagen I synthesis. Finally, we found that CD38 inhibitors, nicotinamide and telmisartan significantly improved the endothelium-independent contraction and vascular remodeling, which was also associated with the inhibition of NLRP3 inflammasome in the aorta media in the diabetic mice. SIGNIFICANCE: Our data suggested that CD38/cADPR-mediated Ca2+ signaling contributed to the mitochondrial damage, consequently released mtDNA to the cytosol, which was related with NLRP3 inflammasome activation and VSMCs remodeling in diabetic mice.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Cálcio/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Inflamassomos/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Sinalização do Cálcio/fisiologia , ADP-Ribose Cíclica/metabolismo , DNA Mitocondrial/metabolismo , Diabetes Mellitus Experimental/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/patologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia
9.
PLoS Pathog ; 16(5): e1008543, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32401783

RESUMO

Triggering receptor expressed on myeloid cells 2 (TREM2) serves as an anti-inflammatory receptor, negatively regulating the innate immune response. TREM2 is mainly expressed on dendritic cells and macrophages, the target cells of porcine reproductive and respiratory syndrome virus (PRRSV). Thus, we investigated the potential role of TREM2 in PRRSV infection in porcine alveolar macrophages (PAMs). We found that there was an increased expression of TREM2 upon PRRSV infection in vitro. TREM2 silencing restrained the replication of PRRSV, whereas TREM2 overexpression facilitated viral replication. The cytoplasmic tail domain of TREM2 interacted with PRRSV Nsp2 to promote infection. TREM2 downregulation led to early activation of PI3K/NF-κB signaling, thus reinforcing the expression of proinflammatory cytokines and type I interferons. Due to the enhanced cytokine expression, a disintegrin and metalloproteinase 17 was activated to promote the cleavage of membrane CD163, which resulted in suppression of infection. Furthermore, exogenous soluble TREM2 (sTREM2)-mediated inhibition of PRRSV attachment might be attributed to its competitive binding to viral envelope proteins. In pigs, following PRRSV challenge in vivo, the expression of TREM2 in lungs and lymph nodes as well as the production of sTREM2 were significantly increased. These novel findings indicate that TREM2 plays a role in regulating PRRSV replication via the inflammatory response. Therefore, our work describes a novel antiviral mechanism against PRRSV infection and suggests that targeting TREM2 could be a new approach in the control of the PRRSV infection.


Assuntos
Glicoproteínas de Membrana/imunologia , NF-kappa B/imunologia , Fosfatidilinositol 3-Quinases/imunologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Transdução de Sinais/imunologia , Animais , Inflamação/imunologia , Inflamação/patologia , Inflamação/virologia , Síndrome Respiratória e Reprodutiva Suína/patologia , Suínos
10.
J Virol ; 94(14)2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32376627

RESUMO

The 2019 coronavirus disease (COVID-19), caused by the emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has posed serious threats to global public health and economic and social stabilities, calling for the prompt development of therapeutics and prophylactics. In this study, we first verified that SARS-CoV-2 uses human angiotensin-converting enzyme 2 (ACE2) as a cell receptor and that its spike (S) protein mediates high membrane fusion activity. The heptad repeat 1 (HR1) sequence in the S2 fusion protein of SARS-CoV-2 possesses markedly increased α-helicity and thermostability, as well as a higher binding affinity with its corresponding heptad repeat 2 (HR2) site, than the HR1 sequence in S2 of severe acute respiratory syndrome coronavirus (SARS-CoV). Then, we designed an HR2 sequence-based lipopeptide fusion inhibitor, termed IPB02, which showed highly potent activities in inhibiting SARS-CoV-2 S protein-mediated cell-cell fusion and pseudovirus transduction. IPB02 also inhibited the SARS-CoV pseudovirus efficiently. Moreover, the structure-activity relationship (SAR) of IPB02 was characterized with a panel of truncated lipopeptides, revealing the amino acid motifs critical for its binding and antiviral capacities. Therefore, the results presented here provide important information for understanding the entry pathway of SARS-CoV-2 and the design of antivirals that target the membrane fusion step.IMPORTANCE The COVID-19 pandemic, caused by SARS-CoV-2, presents a serious global public health emergency in urgent need of prophylactic and therapeutic interventions. The S protein of coronaviruses mediates viral receptor binding and membrane fusion, thus being considered a critical target for antivirals. Herein, we report that the SARS-CoV-2 S protein has evolved a high level of activity to mediate cell-cell fusion, significantly differing from the S protein of SARS-CoV that emerged previously. The HR1 sequence in the fusion protein of SARS-CoV-2 adopts a much higher helical stability than the HR1 sequence in the fusion protein of SARS-CoV and can interact with the HR2 site to form a six-helical bundle structure more efficiently, underlying the mechanism of the enhanced fusion capacity. Also, importantly, the design of membrane fusion inhibitors with high potencies against both SARS-CoV-2 and SARS-CoV has provided potential arsenals to combat the pandemic and tools to exploit the fusion mechanism.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Lipopeptídeos/farmacologia , Fusão de Membrana/efeitos dos fármacos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Sequência de Aminoácidos , Betacoronavirus/fisiologia , Desenho de Fármacos , Células HEK293 , Humanos , Lipopeptídeos/química , Glicoproteínas de Membrana/metabolismo , Pandemias , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Proteínas do Envelope Viral/metabolismo
11.
Radiology ; 295(3): 606-615, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32255416

RESUMO

Background Current measurements of multiple myeloma disease burden are suboptimal. Daratumumab is a monoclonal antibody that targets CD38, an antigen expressed on nearly all myeloma cells. Purpose To demonstrate preclinical and first-in-human application of an antibody composed of the native daratumumab labeled with the positron-emitting radionuclide zirconium 89 (89Zr) through the chelator deferoxamine (DFO), or 89Zr-DFO-daratumumab, for immunologic PET imaging of multiple myeloma. Materials and Methods 89Zr-DFO-daratumumab was synthesized by conjugating 89Zr to daratumumab with DFO. A murine xenograft model using CD38-positive OPM2 multiple myeloma cells was used to evaluate CD38-specificity of 89Zr-DFO-daratumumab. Following successful preclinical imaging, a prospective phase I study of 10 patients with multiple myeloma was performed. Study participants received 74 MBq (2 mCi) of intravenous 89Zr-DFO-daratumumab. Each participant underwent four PET/CT scans over the next 8 days, as well as blood chemistry and whole-body counts, to determine safety, tracer biodistribution, pharmacokinetics, and radiation dosimetry. Because 89Zr has a half-life of 78 hours, only a single administration of tracer was needed to obtain all four PET/CT scans. Results 89Zr-DFO-daratumumab was synthesized with radiochemical purity greater than 99%. In the murine model, substantial bone marrow uptake was seen in OPM2 mice but not in healthy mice, consistent with CD38-targeted imaging of OPM2 multiple myeloma cells. In humans, 89Zr-DFO-daratumumab was safe and demonstrated acceptable dosimetry. 89Zr-DFO-daratumumab uptake was visualized at PET in sites of osseous myeloma. Conclusion These data demonstrate successful CD38-targeted immunologic PET imaging of multiple myeloma in a murine model and in humans. © RSNA, 2020 Online supplemental material is available for this article.


Assuntos
ADP-Ribosil Ciclase 1 , Neoplasias Ósseas/diagnóstico por imagem , Modelos Animais de Doenças , Glicoproteínas de Membrana , Mieloma Múltiplo/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Animais , Anticorpos Monoclonais , Desferroxamina , Xenoenxertos , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade , Carga Tumoral , Zircônio
12.
Science ; 368(6489)2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32327568

RESUMO

Misfolded luminal endoplasmic reticulum (ER) proteins undergo ER-associated degradation (ERAD-L): They are retrotranslocated into the cytosol, polyubiquitinated, and degraded by the proteasome. ERAD-L is mediated by the Hrd1 complex (composed of Hrd1, Hrd3, Der1, Usa1, and Yos9), but the mechanism of retrotranslocation remains mysterious. Here, we report a structure of the active Hrd1 complex, as determined by cryo-electron microscopy analysis of two subcomplexes. Hrd3 and Yos9 jointly create a luminal binding site that recognizes glycosylated substrates. Hrd1 and the rhomboid-like Der1 protein form two "half-channels" with cytosolic and luminal cavities, respectively, and lateral gates facing one another in a thinned membrane region. These structures, along with crosslinking and molecular dynamics simulation results, suggest how a polypeptide loop of an ERAD-L substrate moves through the ER membrane.


Assuntos
Proteínas de Transporte/química , Degradação Associada com o Retículo Endoplasmático , Glicoproteínas de Membrana/química , Proteínas de Membrana/química , Complexos Multiproteicos/química , Proteólise , Proteínas de Saccharomyces cerevisiae/química , Ubiquitina-Proteína Ligases/química , Proteínas de Transporte/metabolismo , Microscopia Crioeletrônica , Retículo Endoplasmático/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Simulação de Dinâmica Molecular , Complexos Multiproteicos/metabolismo , Domínios Proteicos , Dobramento de Proteína , Proteínas de Saccharomyces cerevisiae/metabolismo
13.
Nat Commun ; 11(1): 1729, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32265438

RESUMO

The TrkB receptor is critical for the control of energy balance, as mutations in its gene (NTRK2) lead to hyperphagia and severe obesity. The main neural substrate mediating the appetite-suppressing activity of TrkB, however, remains unknown. Here, we demonstrate that selective Ntrk2 deletion within paraventricular hypothalamus (PVH) leads to severe hyperphagic obesity. Furthermore, chemogenetic activation or inhibition of TrkB-expressing PVH (PVHTrkB) neurons suppresses or increases food intake, respectively. PVHTrkB neurons project to multiple brain regions, including ventromedial hypothalamus (VMH) and lateral parabrachial nucleus (LPBN). We find that PVHTrkB neurons projecting to LPBN are distinct from those to VMH, yet Ntrk2 deletion in PVH neurons projecting to either VMH or LPBN results in hyperphagia and obesity. Additionally, TrkB activation with BDNF increases firing of these PVH neurons. Therefore, TrkB signaling is a key regulator of a previously uncharacterized neuronal population within the PVH that impinges upon multiple circuits to govern appetite.


Assuntos
Hiperfagia/metabolismo , Glicoproteínas de Membrana/metabolismo , Neurônios/metabolismo , Obesidade/metabolismo , Núcleo Hipotalâmico Paraventricular/citologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Apetite/genética , Comportamento Alimentar/fisiologia , Feminino , Hiperfagia/genética , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/genética , Núcleos Parabraquiais/citologia , Núcleos Parabraquiais/metabolismo , Núcleos Parabraquiais/fisiopatologia , Proteínas Tirosina Quinases/genética , Núcleo Hipotalâmico Ventromedial/citologia , Núcleo Hipotalâmico Ventromedial/metabolismo
14.
Biochim Biophys Acta Proteins Proteom ; 1868(7): 140426, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272193

RESUMO

Lipotoxicity, an important factor in the pathogenesis of diabetes, leads to defective ß-cell proliferation and increased apoptosis. Glucagon-like peptide-1 (GLP-1) analogs, which are used to treat type 2 diabetes, reduce endoplasmic reticulum stress and inflammation in pancreatic ß-cells and improve their survival. However, their effects on the heat shock response (HSR) have not been elucidated yet. We investigated whether the GLP-1 analog exendin-4 exerts its protective effect by modulating the HSR and mitogen-activated protein kinases (MAPKs) in BTC-6 mouse pancreatic cells under palmitic acid (PA) stress. Expression patterns were analyzed using mass spectrometry, Western blotting, and qRT-PCR in the presence of 250 or 400 µM PA and 100 nM exendin-4. Additionally, we measured MAPK expression and phosphorylation using qRT-PCR and Western blotting, respectively. Upregulation of heat shock protein (HSP), notably HSP72, in the presence of PA, was attenuated by exendin-4. Despite the absence of global effects on the HSR system, exendin-4 attenuated the expression of other non-classical HSPs (GRP94, DNAJA1, and DNAJB6) in the presence of PA. Regarding MAPKs, only extracellular signal-regulated kinase (ERK) phosphorylation was highly increased by exendin-4 in both the presence and absence of PA. Furthermore, exendin-4 significantly alleviated PA-induced cell death, which was further confirmed with proteomics analysis where key cellular functions, including cellular growth, assembly, and organization, were improved by exendin-4 treatment. Thus, our results expand the protective role of GLP-1 analogs to include other cellular mechanisms involved in restoring normal ß-cell homeostasis.


Assuntos
Exenatida/metabolismo , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Proteínas de Choque Térmico HSP72/metabolismo , Células Secretoras de Insulina/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Exenatida/farmacologia , Proteínas de Choque Térmico HSP40 , Glicoproteínas de Membrana , Camundongos , Chaperonas Moleculares , Fosforilação , Substâncias Protetoras/farmacologia , Mapas de Interação de Proteínas , Regulação para Cima
15.
PLoS One ; 15(4): e0231379, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302347

RESUMO

This randomized, double-blinded, placebo-controlled trial tested the hypothesis that 20mg of melatonin before and during the first cycle of adjuvant chemotherapy for breast cancer (ACBC) reduced the side effects associated with cognitive impairment. We evaluated the effects of melatonin on cognition, depressive symptoms and sleep quality, and whether these effects were related to serum levels of Brain Derived Neurotrophic Factor (BDNF) and its receptor, tropomyosin kinase B (TrkB). Thirty-six women were randomly assigned to receive melatonin or placebo for 10 days. To evaluate cognitive performance, we used the Trail-Making-Test Parts A and B (A-B), Rey Auditory-Verbal Learning Test (RAVLT), Controlled Oral Word Association Test (COWAT) and an inhibitory task type Go / No-Go. Our results revealed that melatonin improved executive function on TMT scores, enhanced episodic memory (immediate and delayed) and recognition on RAVLT, and increased verbal fluency in the orthographic COWAT. The TMT-A-B(A-B) were negatively correlated with baseline levels of TrkB and BDNF, respectively. At the end of treatment, changes in TrkB and BDNF were inversely associated with depressive symptoms and sleep quality, but not with the TMT scores. These results suggest a neuroprotective effect of melatonin to counteract the adverse effects of ACBC on cognitive function, sleep quality and depressive symptoms.


Assuntos
Neoplasias da Mama/patologia , Disfunção Cognitiva/prevenção & controle , Depressão/tratamento farmacológico , Melatonina/uso terapêutico , Sono , Adulto , Idoso , Antineoplásicos/uso terapêutico , Biomarcadores/sangue , Fator Neurotrófico Derivado do Encéfalo/sangue , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Depressão/etiologia , Método Duplo-Cego , Feminino , Humanos , Melatonina/farmacologia , Glicoproteínas de Membrana/sangue , Pessoa de Meia-Idade , Testes Neuropsicológicos , Efeito Placebo , Receptor trkB/sangue , Sono/efeitos dos fármacos , Resultado do Tratamento
16.
J Nucl Med ; 61(5): 632-636, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32238429

RESUMO

Infection with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may remain asymptomatic, leading to under-recognition of the related disease, coronavirus disease, 2019 (COVID-19), and to incidental findings in nuclear imaging procedures performed for standard clinical indications. Here, we report about our local experience in a region with high COVID-19 prevalence and dynamically increasing infection rates. Methods: Within the 8-d period of March 16-24, 2020, hybrid imaging studies of asymptomatic patients who underwent 18F-FDG PET/CT or 131I SPECT/CT for standard oncologic indications at our institution in Brescia, Italy, were analyzed for findings suggestive of COVID-19. The presence, radiologic features, and metabolic activity of interstitial pneumonia were identified, correlated with the subsequent short-term clinical course, and described in a case series. Results: Six of 65 patients (9%) who underwent PET/CT for various malignancies showed unexpected signs of interstitial pneumonia on CT and elevated regional 18F-FDG avidity. Additionally, 1 of 12 patients who received radioiodine for differentiated thyroid carcinoma also showed interstitial pneumonia on SPECT/CT. Five of 7 patients had subsequent proof of COVID-19 by reverse-transcriptase polymerase chain reaction. The remaining 2 patients were not tested immediately but underwent quarantine and careful monitoring. Conclusion: Incidental findings suggestive of COVID-19 may not be infrequent in hybrid imaging of asymptomatic patients in regions with an expansive spread of SARS-CoV-2. Nuclear medicine services should prepare accordingly.


Assuntos
Infecções por Coronavirus/diagnóstico , Achados Incidentais , Doenças Pulmonares Intersticiais , Pneumonia Viral/diagnóstico , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Idoso , Doenças Assintomáticas , Betacoronavirus , Infecções por Coronavirus/complicações , Feminino , Fluordesoxiglucose F18 , Humanos , Controle de Infecções , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/etiologia , Masculino , Glicoproteínas de Membrana , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Medicina Nuclear/tendências , Pandemias , Pneumonia Viral/complicações , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
17.
Life Sci ; 251: 117609, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32272180

RESUMO

AIMS: To identify the target of an adipose specific aptamer adipo-8, predict the potential interaction between adipo-8 and its target, and investigate lipid-lowering effect of adipo-8 in vitro and in vivo. MAIN METHODS: Distinct membranous protein of 3T3-L1 adipocyte pulled-down by adipo-8 was mass-spectrometry analyzed as target candidate(s), and affinity of adipo-8 to target protein-silent adipocyte was detected to validate it. Interaction between adipo-8 and target was predicted by bioinformatic analysis, further confirmed by aptamer truncation and competitive binding assay. To investigate lipid-lowering effect of adipo-8 and mechanism behind, 250 nmol/L adipo-8 or library was incubated with 3T3-L1 adipocyte or target-protein-silent adipocyte for 24 h, and 0.01 µg/g/day adipo-8 or library was administrated to high-fat-fed male mice for 21 days. KEY FINDINGS: APMAP (Adipocyte Plasma Membrane Associated Protein) was identified as adipo-8 target, and adipo-8 affinity to adipocytes was in proportional to APMAP expression. Docking model between the stem-loop structure of adipo-8 and APMAP were predicted that adipo-8 was likely to interact with APMAP at its amino-acid 275-411 sequence. Moreover, adipo-8 could ameliorate fat deposition through interaction with APMAP in vitro, and administration of adipo-8 in high-fat-diet fed mice resulted in body weight loss and blood triglyceride decrease without liver or renal dysfunction. SIGNIFICANCE: Adipo-8 could recognize APMAP specifically and interact with its targets to ameliorate fat deposition in vitro and in vivo. Aptamer adipo-8 has potential to act as an effective and safe targeted drug for obesity and obesity related diseases.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , Glicoproteínas de Membrana/metabolismo , Células 3T3-L1 , Animais , Dieta Hiperlipídica , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular
18.
Cancer Immunol Immunother ; 69(7): 1237-1252, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32166404

RESUMO

Clear cell renal cell carcinoma (ccRCC) constitutes the most common renal cell carcinoma subtype and has long been recognized as an immunogenic cancer. As such, significant attention has been directed toward optimizing immune-checkpoints (IC)-based therapies. Despite proven benefits, a substantial number of patients remain unresponsive to treatment, suggesting that yet unreported, immunosuppressive mechanisms coexist within tumors and their microenvironment. Here, we comprehensively analyzed and ranked forty-four immune-checkpoints expressed in ccRCC on the basis of in-depth analysis of RNAseq data collected from the TCGA database and advanced statistical methods designed to obtain the group of checkpoints that best discriminates tumor from healthy tissues. Immunohistochemistry and flow cytometry confirmed and enlarged the bioinformatics results. In particular, by using the recursive feature elimination method, we show that HLA-G, B7H3, PDL-1 and ILT2 are the most relevant genes that characterize ccRCC. Notably, ILT2 expression was detected for the first time on tumor cells. The levels of other ligand-receptor pairs such as CD70:CD27; 4-1BB:4-1BBL; CD40:CD40L; CD86:CTLA4; MHC-II:Lag3; CD200:CD200R; CD244:CD48 were also found highly expressed in tumors compared to adjacent non-tumor tissues. Collectively, our approach provides a comprehensible classification of forty-four IC expressed in ccRCC, some of which were never reported before to be co-expressed in ccRCC. In addition, the algorithms used allowed identifying the most relevant group that best discriminates tumor from healthy tissues. The data can potentially assist on the choice of valuable immune-therapy targets which hold potential for the development of more effective anti-tumor treatments.


Assuntos
Antígenos CD/imunologia , Biomarcadores Tumorais/imunologia , Carcinoma de Células Renais/imunologia , Antígenos HLA-G/imunologia , Neoplasias Renais/imunologia , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/imunologia , Glicoproteínas de Membrana/imunologia , Receptores Imunológicos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/patologia , Estudos de Casos e Controles , Feminino , Seguimentos , Perfilação da Expressão Gênica , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
19.
Proc Natl Acad Sci U S A ; 117(11): 5761-5771, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32132203

RESUMO

The circadian clock coordinates a variety of immune responses with signals from the external environment to promote survival. We investigated the potential reciprocal relationship between the circadian clock and skin inflammation. We treated mice topically with the Toll-like receptor 7 (TLR7) agonist imiquimod (IMQ) to activate IFN-sensitive gene (ISG) pathways and induce psoriasiform inflammation. IMQ transiently altered core clock gene expression, an effect mirrored in human patient psoriatic lesions. In mouse skin 1 d after IMQ treatment, ISGs, including the key ISG transcription factor IFN regulatory factor 7 (Irf7), were more highly induced after treatment during the day than the night. Nuclear localization of phosphorylated-IRF7 was most prominently time-of-day dependent in epidermal leukocytes, suggesting that these cell types play an important role in the diurnal ISG response to IMQ. Mice lacking Bmal1 systemically had exacerbated and arrhythmic ISG/Irf7 expression after IMQ. Furthermore, daytime-restricted feeding, which affects the phase of the skin circadian clock, reverses the diurnal rhythm of IMQ-induced ISG expression in the skin. These results suggest a role for the circadian clock, driven by BMAL1, as a negative regulator of the ISG response, and highlight the finding that feeding time can modulate the skin immune response. Since the IFN response is essential for the antiviral and antitumor effects of TLR activation, these findings are consistent with the time-of-day-dependent variability in the ability to fight microbial pathogens and tumor initiation and offer support for the use of chronotherapy for their treatment.


Assuntos
Ritmo Circadiano , Imunidade Inata/genética , Interferons/genética , Glicoproteínas de Membrana/genética , Pele/metabolismo , Receptor 7 Toll-Like/genética , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Imiquimode/farmacologia , Indutores de Interferon/farmacologia , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/metabolismo , Interferons/metabolismo , Masculino , Glicoproteínas de Membrana/agonistas , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Pele/efeitos dos fármacos , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/metabolismo
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