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1.
Nat Immunol ; 24(1): 123-135, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36550322

RESUMO

Naive CD4+ T lymphocytes initially undergo antigen-specific activation to promote a broad-spectrum response before adopting bespoke cytokine expression profiles shaped by intercellular microenvironmental cues, resulting in pathogen-focused modular cytokine responses. Interleukin (IL)-4-induced Gata3 upregulation is important for the helper type 2 T cell (TH2 cell) polarization associated with anti-helminth immunity and misdirected allergic inflammation. Whether additional microenvironmental factors participate is unclear. Using whole mouse-genome CRISPR-Cas9 screens, we discovered a previously unappreciated role for αvß3 integrin in TH2 cell differentiation. Low-level αvß3 expression by naive CD4+ T cells contributed to pan-T cell activation by promoting T-T cell clustering and IL-2/CD25/STAT5 signaling. Subsequently, IL-4/Gata3-induced selective upregulation of αvß3 licensed intercellular αvß3-Thy1 interactions among TH2 cells, enhanced mammalian target of rapamycin (mTOR) signaling, supported differentiation and promoted IL-5/IL-13 production. In mice, αvß3 was required for efficient, allergen-driven, antigen-specific lung TH2 cell responses. Thus, αvß3-expressing TH2 cells form multicellular factories to propagate and amplify TH2 cell responses.


Assuntos
Citocinas , Células Th2 , Camundongos , Animais , Citocinas/metabolismo , Diferenciação Celular , Alérgenos , Pulmão , Mamíferos/metabolismo
2.
Nat Immunol ; 22(2): 166-178, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33432227

RESUMO

Type 2 innate lymphoid cells (ILC2) contribute to immune homeostasis, protective immunity and tissue repair. Here we demonstrate that functional ILC2 cells can arise in the embryonic thymus from shared T cell precursors, preceding the emergence of CD4+CD8+ (double-positive) T cells. Thymic ILC2 cells migrated to mucosal tissues, with colonization of the intestinal lamina propria. Expression of the transcription factor RORα repressed T cell development while promoting ILC2 development in the thymus. From RNA-seq, assay for transposase-accessible chromatin sequencing (ATAC-seq) and chromatin immunoprecipitation followed by sequencing (ChIP-seq) data, we propose a revised transcriptional circuit to explain the co-development of T cells and ILC2 cells from common progenitors in the thymus. When Notch signaling is present, BCL11B dampens Nfil3 and Id2 expression, permitting E protein-directed T cell commitment. However, concomitant expression of RORα overrides the repression of Nfil3 and Id2 repression, allowing ID2 to repress E proteins and promote ILC2 differentiation. Thus, we demonstrate that RORα expression represents a critical checkpoint at the bifurcation of the T cell and ILC2 lineages in the embryonic thymus.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Linhagem da Célula , Imunidade Inata , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Timócitos/metabolismo , Timo/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Movimento Celular , Células Cultivadas , Técnicas de Cocultura , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteína 2 Inibidora de Diferenciação/genética , Proteína 2 Inibidora de Diferenciação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Técnicas de Cultura de Órgãos , Fenótipo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Timócitos/imunologia , Timo/embriologia , Timo/imunologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
3.
Immunity ; 56(7): 1468-1484.e7, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37285842

RESUMO

Type 2 immune responses are critical in tissue homeostasis, anti-helminth immunity, and allergy. T helper 2 (Th2) cells produce interleukin-4 (IL-4), IL-5, and IL-13 from the type 2 gene cluster under regulation by transcription factors (TFs) including GATA3. To better understand transcriptional regulation of Th2 cell differentiation, we performed CRISPR-Cas9 screens targeting 1,131 TFs. We discovered that activity-dependent neuroprotector homeobox protein (ADNP) was indispensable for immune reactions to allergen. Mechanistically, ADNP performed a previously unappreciated role in gene activation, forming a critical bridge in the transition from pioneer TFs to chromatin remodeling by recruiting the helicase CHD4 and ATPase BRG1. Although GATA3 and AP-1 bound the type 2 cytokine locus in the absence of ADNP, they were unable to initiate histone acetylation or DNA accessibility, resulting in highly impaired type 2 cytokine expression. Our results demonstrate an important role for ADNP in promoting immune cell specialization.


Assuntos
Histonas , Fatores de Transcrição , Histonas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica , Células Th2 , Citocinas/metabolismo , Diferenciação Celular , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo
4.
Nature ; 623(7989): 1053-1061, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37844613

RESUMO

Inflammation is a hallmark of cancer1. In patients with cancer, peripheral blood myeloid expansion, indicated by a high neutrophil-to-lymphocyte ratio, associates with shorter survival and treatment resistance across malignancies and therapeutic modalities2-5. Whether myeloid inflammation drives progression of prostate cancer in humans remain unclear. Here we show that inhibition of myeloid chemotaxis can reduce tumour-elicited myeloid inflammation and reverse therapy resistance in a subset of patients with metastatic castration-resistant prostate cancer (CRPC). We show that a higher blood neutrophil-to-lymphocyte ratio reflects tumour myeloid infiltration and tumour expression of senescence-associated mRNA species, including those that encode myeloid-chemoattracting CXCR2 ligands. To determine whether myeloid cells fuel resistance to androgen receptor signalling inhibitors, and whether inhibiting CXCR2 to block myeloid chemotaxis reverses this, we conducted an investigator-initiated, proof-of-concept clinical trial of a CXCR2 inhibitor (AZD5069) plus enzalutamide in patients with metastatic CRPC that is resistant to androgen receptor signalling inhibitors. This combination was well tolerated without dose-limiting toxicity and it decreased circulating neutrophil levels, reduced intratumour CD11b+HLA-DRloCD15+CD14- myeloid cell infiltration and imparted durable clinical benefit with biochemical and radiological responses in a subset of patients with metastatic CRPC. This study provides clinical evidence that senescence-associated myeloid inflammation can fuel metastatic CRPC progression and resistance to androgen receptor blockade. Targeting myeloid chemotaxis merits broader evaluation in other cancers.


Assuntos
Antagonistas de Receptores de Andrógenos , Antineoplásicos , Quimiotaxia , Resistencia a Medicamentos Antineoplásicos , Células Mieloides , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Quimiotaxia/efeitos dos fármacos , Progressão da Doença , Inflamação/tratamento farmacológico , Inflamação/patologia , Antígenos CD15/metabolismo , Células Mieloides/efeitos dos fármacos , Células Mieloides/patologia , Metástase Neoplásica , Próstata/efeitos dos fármacos , Próstata/metabolismo , Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
5.
Immunity ; 51(1): 104-118.e7, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31128961

RESUMO

Innate lymphoid cells (ILCs) play strategic roles in tissue homeostasis and immunity. ILCs arise from lymphoid progenitors undergoing lineage restriction and the development of specialized ILC subsets. We generated "5x polychromILC" transcription factor reporter mice to delineate ILC precursor states by revealing the multifaceted expression of key ILC-associated transcription factors (Id2, Bcl11b, Gata3, RORγt, and RORα) during ILC development in the bone marrow. This approach allowed previously unattained enrichment of rare progenitor subsets and revealed hitherto unappreciated ILC precursor heterogeneity. In vivo and in vitro assays identified precursors with potential to generate all ILC subsets and natural killer (NK) cells, and also permitted discrimination of elusive ILC3 bone marrow antecedents. Single-cell gene expression analysis identified a discrete ILC2-committed population and delineated transition states between early progenitors and a highly heterogeneous ILC1, ILC3, and NK precursor cell cluster. This diversity might facilitate greater lineage potential upon progenitor recruitment to peripheral tissues.


Assuntos
Medula Óssea/imunologia , Subpopulações de Linfócitos/fisiologia , Linfócitos/fisiologia , Células Progenitoras Linfoides/fisiologia , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Imunidade Inata , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Análise de Célula Única , Fatores de Transcrição/genética
6.
Cell ; 145(3): 398-409, 2011 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-21529713

RESUMO

Sickle human hemoglobin (Hb) confers a survival advantage to individuals living in endemic areas of malaria, the disease caused by Plasmodium infection. As demonstrated hereby, mice expressing sickle Hb do not succumb to experimental cerebral malaria (ECM). This protective effect is exerted irrespectively of parasite load, revealing that sickle Hb confers host tolerance to Plasmodium infection. Sickle Hb induces the expression of heme oxygenase-1 (HO-1) in hematopoietic cells, via a mechanism involving the transcription factor NF-E2-related factor 2 (Nrf2). Carbon monoxide (CO), a byproduct of heme catabolism by HO-1, prevents further accumulation of circulating free heme after Plasmodium infection, suppressing the pathogenesis of ECM. Moreover, sickle Hb inhibits activation and/or expansion of pathogenic CD8(+) T cells recognizing antigens expressed by Plasmodium, an immunoregulatory effect that does not involve Nrf2 and/or HO-1. Our findings provide insight into molecular mechanisms via which sickle Hb confers host tolerance to severe forms of malaria.


Assuntos
Hemoglobina Falciforme/imunologia , Malária/imunologia , Plasmodium berghei , Animais , Linfócitos T CD8-Positivos/imunologia , Monóxido de Carbono/metabolismo , Quimiocinas/metabolismo , Cruzamentos Genéticos , Modelos Animais de Doenças , Heme Oxigenase-1/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Malária/fisiopatologia , Malária Cerebral/imunologia , Malária Cerebral/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo
7.
Mol Cell Proteomics ; 23(3): 100722, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272115

RESUMO

Glioblastoma (GBM) is the most aggressive brain tumor and different efforts have been employed in the search for new drugs and therapeutic protocols for GBM. Epitranscriptomics has shed light on new druggable Epigenetic therapies specifically designed to modulate GBM biology and behavior such as Histone Deacetylase inhibitors (iHDAC). Although the effects of iHDAC on GBM have been largely explored, there is a lack of information on the underlaying mechanisms HDAC-dependent that modulate the repertoire of GBM secreted molecules focusing on the set of Extracellular Matrix (ECM) associated proteins, the Matrisome, that may impact the surrounding tumor microenvironment. To acquire a better comprehension of the impacts of HDAC activity on the GBM Matrisome, we studied the alterations on the Matrisome-associated ECM regulators, Core Matrisome ECM glycoproteins, ECM-affiliated proteins and Proteoglycans upon HDAC inhibition in vitro as well as their relationship with glioma pathophysiological/clinical features and angiogenesis. For this, U87MG GBM cells were treated for with iHDAC or vehicle (control) and the whole secretome was processed by Mass Spectrometry NANOLC-MS/MS. In silico analyses revealed that proteins associated to the Angiogenic Matrisome (AngioMatrix), including Decorin, ADAM10, ADAM12 and ADAM15 were differentially regulated in iHDAC versus control secretome. Interestingly, genes coding for the Matrisome proteins differentially regulated were found mutated in patients and were correlated to glioma pathophysiological/clinical features. In vitro functional assays, using HBMEC endothelial cells exposed to the secretome of control or iHDAC treated GBM cells, coupled to 2D and 3D GBM cell culture system, showed impaired migratory capacity of endothelial cells and disrupted tubulogenesis in a Fibronectin and VEGF independent fashion. Collectively, our study provides understanding of epigenetic mechanisms HDAC-dependent to key Matrisomal proteins that may contribute to identify new druggable Epigenetic therapies or gliomagenesis biomarkers with relevant implications to improve therapeutic protocols for this malignancy.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Glioblastoma/genética , Glioblastoma/patologia , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Células Endoteliais/metabolismo , Espectrometria de Massas em Tandem , Matriz Extracelular/metabolismo , Glioma/metabolismo , Epigênese Genética , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Microambiente Tumoral , Proteínas de Membrana/metabolismo , Proteínas ADAM/metabolismo
8.
Proc Natl Acad Sci U S A ; 119(49): e2203454119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442116

RESUMO

The development of innate lymphoid cell (ILC) transcription factor reporter mice has shown a previously unexpected complexity in ILC hematopoiesis. Using novel polychromic mice to achieve higher phenotypic resolution, we have characterized bone marrow progenitors that are committed to the group 1 ILC lineage. These common ILC1/NK cell progenitors (ILC1/NKP), which we call "aceNKPs", are defined as lineage-Id2+IL-7Rα+CD25-α4ß7-NKG2A/C/E+Bcl11b-. In vitro, aceNKPs differentiate into group 1 ILCs, including NK-like cells that express Eomes without the requirement for IL-15, and produce IFN-γ and perforin upon IL-15 stimulation. Following reconstitution of Rag2-/-Il2rg-/- hosts, aceNKPs give rise to a spectrum of mature ILC1/NK cells (regardless of their tissue location) that cannot be clearly segregated into the traditional ILC1 and NK subsets, suggesting that group 1 ILCs constitute a dynamic continuum of ILCs that can develop from a common progenitor. In addition, aceNKP-derived ILC1/NK cells effectively ameliorate tumor burden in a model of lung metastasis, where they acquired a cytotoxic NK cell phenotype. Our results identify the primary ILC1/NK progenitor that lacks ILC2 or ILC3 potential and is strictly committed to ILC1/NK cell production irrespective of tissue homing.


Assuntos
Imunidade Inata , Interleucina-15 , Animais , Camundongos , Interleucina-15/genética , Células Matadoras Naturais , Perforina , Fatores de Transcrição , Proteínas Repressoras , Proteínas Supressoras de Tumor
9.
Neurobiol Dis ; 193: 106456, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423193

RESUMO

Spinocerebellar ataxia type 3 (SCA3)/Machado-Joseph disease (MJD) is a heritable proteinopathy disorder, whose causative gene, ATXN3, undergoes alternative splicing. Ataxin-3 protein isoforms differ in their toxicity, suggesting that certain ATXN3 splice variants may be crucial in driving the selective toxicity in SCA3. Using RNA-seq datasets we identified and determined the abundance of annotated ATXN3 transcripts in blood (n = 60) and cerebellum (n = 12) of SCA3 subjects and controls. The reference transcript (ATXN3-251), translating into an ataxin-3 isoform harbouring three ubiquitin-interacting motifs (UIMs), showed the highest abundance in blood, while the most abundant transcript in the cerebellum (ATXN3-208) was of unclear function. Noteworthy, two of the four transcripts that encode full-length ataxin-3 isoforms but differ in the C-terminus were strongly related with tissue expression specificity: ATXN3-251 (3UIM) was expressed in blood 50-fold more than in the cerebellum, whereas ATXN3-214 (2UIM) was expressed in the cerebellum 20-fold more than in the blood. These findings shed light on ATXN3 alternative splicing, aiding in the comprehension of SCA3 pathogenesis and providing guidance in the design of future ATXN3 mRNA-lowering therapies.


Assuntos
Doença de Machado-Joseph , Humanos , Doença de Machado-Joseph/metabolismo , Ataxina-3/genética , Ataxina-3/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Cerebelo/patologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
10.
Am J Physiol Heart Circ Physiol ; 326(5): H1193-H1203, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38334973

RESUMO

Pressure overload-induced hypertrophy compromises cardiac stretch-induced compliance (SIC) after acute volume overload (AVO). We hypothesized that SIC could be enhanced by physiological hypertrophy induced by pregnancy's chronic volume overload. This study evaluated SIC-cardiac adaptation in pregnant women with or without cardiovascular risk (CVR) factors. Thirty-seven women (1st trimester, 1stT) and a separate group of 31 (3rd trimester, 3rdT) women [healthy or with CVR factors (obesity and/or hypertension and/or with gestational diabetes)] underwent echocardiography determination of left ventricular end-diastolic volume (LVEDV) and E/e' before (T0), immediately after (T1), and 15 min after (T2; SIC) AVO induced by passive leg elevation. Blood samples for NT-proBNP quantification were collected before and after the AVO. Acute leg elevation significantly increased inferior vena cava diameter and stroke volume from T0 to T1 in both 1stT and 3rdT, confirming AVO. LVEDV and E/e' also increased immediately after AVO (T1) in both 1stT and 3rdT. SIC adaptation (T2, 15 min after AVO) significantly decreased E/e' in both trimesters, with additional expansion of LVEDV only in the 1stT. NT-pro-BNP increased slightly after AVO but only in the 1stT. CVR factors, but not parity or age, significantly impacted SIC cardiac adaptation. A distinct functional response to SIC was observed between 1stT and 3rdT, which was influenced by CVR factors. The LV of 3rdT pregnant women was hypertrophied, showing a structural limitation to dilate with AVO, whereas the lower LV filling pressure values suggest increased diastolic compliance.NEW & NOTEWORTHY The sudden increase of volume overload triggers an acute myocardial stretch characterized by an immediate rise in contractility by the Frank-Starling mechanism, followed by a progressive increase known as the slow force response. The present study is the first to characterize echocardiographically the stretch-induced compliance (SIC) mechanism in the context of physiological hypertrophy induced by pregnancy. A distinct functional adaptation to SIC was observed between first and third trimesters, which was influenced by cardiovascular risk factors.


Assuntos
Adaptação Fisiológica , Fatores de Risco de Doenças Cardíacas , Humanos , Feminino , Gravidez , Adulto , Função Ventricular Esquerda , Cardiomegalia/fisiopatologia , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/etiologia , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Complicações Cardiovasculares na Gravidez/fisiopatologia , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Complicações Cardiovasculares na Gravidez/sangue , Volume Sistólico , Terceiro Trimestre da Gravidez , Diabetes Gestacional/fisiopatologia , Complacência (Medida de Distensibilidade) , Primeiro Trimestre da Gravidez , Obesidade/fisiopatologia , Obesidade/complicações , Fatores de Risco
11.
Calcif Tissue Int ; 114(3): 267-275, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38253933

RESUMO

Bone and mineral metabolism abnormalities are frequent in kidney transplant recipients and have been associated with cardiovascular morbidity. The primary aim of this study was to analyse the association between routine clinically available biochemical evaluation, non-routine histomorphometric bone evaluation, and vascular disease in kidney transplanted patients. A cross-sectional analysis was performed on 69 patients, 1-year after kidney transplantation. Laboratory analysis, radiography of hands and pelvis, bone biopsy, bone densitometry, and coronary CT were performed. One-year post-transplantation, nearly one-third of the patients presented with hypercalcemia, 16% had hypophosphatemia, 39.3% had iPTH levels > 150 pg/mL, 20.3% had BALP levels > 40 U/L, and 26.1% had hypovitaminosis D. Evaluation of extraosseous calcifications revealed low Adragão and Agatston scores. We divided patients into three clusters, according to laboratory results routinely used in clinical practice: hypercalcemia and hyperparathyroidism (Cluster1); hypercalcemia and high BALP levels (Cluster2); hypophosphatemia and vitamin D deficiency (Cluster 3). Patients in clusters 1 and 2 had higher cortical porosity (p = 0.001) and osteoid measurements, although there was no difference in the presence of abnormal mineralization, or low volume. Patients in cluster 2 had a higher BFR/BS (half of the patients in cluster 2 had high bone turnover), and most patients in cluster 1 had low or normal bone turnover. Cluster 3 has no differences in volume, or turnover, but 60% of the patients presented with pre-osteomalacia. All three clusters were associated with high vascular calcifications scores. Vascular calcifications scores were not related to higher bone mineral density. Instead, an association was found between a higher Adragão score and the presence of osteoporosis at the femoral neck (p = 0.008). In conclusion, inferring bone TMV by daily clinical biochemical analysis can be misleading, and bone biopsy is important for assessing both bone turnover and mineralization after kidney transplantation, although hypophosphatemia combined with vitamin D deficiency is associated with abnormal mineralization. The presence of hypercalcemia with high levels of PTH or high levels of BALP, or hypophosphatemia and vitamin D deficiency should remind us to screen vascular calcification status of patients.Clinical Research: ClinicalTrials.gov ID NCT02751099.


Assuntos
Hipercalcemia , Hipofosfatemia , Transplante de Rim , Calcificação Vascular , Deficiência de Vitamina D , Humanos , Estudos Transversais , Remodelação Óssea , Deficiência de Vitamina D/complicações , Biópsia , Calcificação Vascular/complicações , Densidade Óssea , Hormônio Paratireóideo
12.
Mol Psychiatry ; 28(9): 3943-3954, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37914840

RESUMO

Functional output of the hippocampus, a brain region subserving memory function, depends on highly orchestrated cellular and molecular processes that regulate synaptic plasticity throughout life. The structural requirements of such plasticity and molecular events involved in this regulation are poorly understood. Specific molecules, including tissue inhibitor of metalloproteinases-2 (TIMP2) have been implicated in plasticity processes in the hippocampus, a role that decreases with brain aging as expression is lost. Here, we report that TIMP2 is highly expressed by neurons within the hippocampus and its loss drives changes in cellular programs related to adult neurogenesis and dendritic spine turnover with corresponding impairments in hippocampus-dependent memory. Consistent with the accumulation of extracellular matrix (ECM) in the hippocampus we observe with aging, we find that TIMP2 acts to reduce accumulation of ECM around synapses in the hippocampus. Moreover, its deletion results in hindrance of newborn neuron migration through a denser ECM network. A novel conditional TIMP2 knockout (KO) model reveals that neuronal TIMP2 regulates adult neurogenesis, accumulation of ECM, and ultimately hippocampus-dependent memory. Our results define a mechanism whereby hippocampus-dependent function is regulated by TIMP2 and its interactions with the ECM to regulate diverse processes associated with synaptic plasticity.


Assuntos
Encéfalo , Plasticidade Neuronal , Recém-Nascido , Humanos , Plasticidade Neuronal/fisiologia , Encéfalo/metabolismo , Neurônios/metabolismo , Hipocampo/metabolismo , Matriz Extracelular/metabolismo , Sinapses/metabolismo , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo
13.
Scand J Gastroenterol ; 59(3): 361-368, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37970898

RESUMO

INTRODUCTION: There is scarce data focused on recurrence neoplasia rate (RR) after piecemeal endoscopic mucosal resection (pEMR) of 10-19 mm non-pedunculated colorectal lesions (NPL). We aimed to analyze the RR after pEMR of 10-19 mm NPL, identify risk factors for its development and compare it with RR after pEMR of ≥ 20 mm NPL. METHODS: Retrospective cohort-study including all ≥10 mm NPL resected by pEMR in our center between 2018-2022 with an early repeat colonoscopy (ERC). RR was defined as recurrence neoplasia identified in the ERC EMR scar with virtual chromoendoscopy or histological confirmation. RESULTS: A total of 444 NPL were assessed, 124 (27.9%) with 10-19 mm. In the ERC, performed a median of 6 months after pEMR, RR was significantly lower for 10-19 mm NPL compared to ≥ 20 mm NPL (13/124 vs 68/320, p = 0.005). In subgroup analysis, RR after pEMR of 15-19 mm NPL was significantly higher compared to 10-14 mm NPL (13/98 vs 0, p = 0.041) but not significantly different compared to ≥ 20 mm NPL (13/98 vs 68/320, p = 0.073). In multivariable analysis, size of NPL (HR 1.501, 95% CI 1.012-2.227, p = 0.044) was the only independent risk factor identified for RR for 10-19 mm NPL. CONCLUSION: Although the early RR after pEMR of 10-19 mm NPL is significantly lower compared to ≥ 20 mm NPL, it is non-negligible (10.5%) and appears to be the highest among 15-19 mm NPL. The size of the lesion was the only independent risk factor for RR. Our findings should be accounted in the selection of the most appropriate post-polypectomy endoscopic surveillance.


Assuntos
Pólipos do Colo , Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Estudos Retrospectivos , Recidiva Local de Neoplasia/epidemiologia , Colonoscopia , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia , Pólipos do Colo/cirurgia , Pólipos do Colo/patologia
14.
Scand J Gastroenterol ; 59(2): 125-132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37872792

RESUMO

BACKGROUND: Gastric dysplasia in the absence of an endoscopically defined lesion is rare, usually either a false positive diagnosis or a previously unidentified precancerous lesion during esophagogastroduodenoscopy (EGD). AIMS: Evaluate factors associated with the presence of an endoscopically visible lesion during follow-up in patients with histologic diagnosis of gastric dysplasia in random biopsies. METHODS: Retrospective cohort study including patients referred to our institution for gastric dysplasia in random biopsies during Index EGD. Endoscopic evaluation was performed with a high-definition endoscope using narrow band imaging (HD EGD-0). If no lesion was detected, endoscopic surveillance (HD EGD-FU) was conducted within 6 months for high grade dysplasia (HGD) or 12 months for low grade (LGD) or indefinite for dysplasia (IFD). RESULTS: From a total sample of 96 patients, 5 (5.2%) presented with an endoscopically visible lesion during HD EGD-0, while 10 lesions (10.4%) were identified during HD EGD-FU. Patients with Helicobacter pylori infection at Index EDG and with regular alcohol consumption (≥25 g/day) were 8 and 4 times more likely to have an endoscopically visible lesion on HD EGD-FU (p = 0.012 and p = 0.047). In binary logistic regression, both factors were independent predictors of the presence of gastric lesion on HD EGD-FU (OR 9.284, p = 0.009 and OR 5.025, p = 0.033). CONCLUSIONS: The presence of an endoscopically visible lesion after the histologic diagnosis of gastric dysplasia in random biopsies was more frequent during HD EGD-FU. H. pylori infection at Index EGD and regular alcohol consumption were significant predictors of the presence of gastric lesion on HD EGD-FU.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Infecções por Helicobacter/epidemiologia , Estudos Retrospectivos , Biópsia , Neoplasias Gástricas/patologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Lesões Pré-Cancerosas/patologia
15.
Brain ; 146(10): 4132-4143, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37071051

RESUMO

Transcriptional dysregulation has been described in spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD), an autosomal dominant ataxia caused by a polyglutamine expansion in the ataxin-3 protein. As ataxin-3 is ubiquitously expressed, transcriptional alterations in blood may reflect early changes that start before clinical onset and might serve as peripheral biomarkers in clinical and research settings. Our goal was to describe enriched pathways and report dysregulated genes, which can track disease onset, severity or progression in carriers of the ATXN3 mutation (pre-ataxic subjects and patients). Global dysregulation patterns were identified by RNA sequencing of blood samples from 40 carriers of ATXN3 mutation and 20 controls and further compared with transcriptomic data from post-mortem cerebellum samples of MJD patients and controls. Ten genes-ABCA1, CEP72, PTGDS, SAFB2, SFSWAP, CCDC88C, SH2B1, LTBP4, MEG3 and TSPOAP1-whose expression in blood was altered in the pre-ataxic stage and simultaneously, correlated with ataxia severity in the overt disease stage, were analysed by quantitative real-time PCR in blood samples from an independent set of 170 SCA3/MJD subjects and 57 controls. Pathway enrichment analysis indicated the Gαi signalling and the oestrogen receptor signalling to be similarly affected in blood and cerebellum. SAFB2, SFSWAP and LTBP4 were consistently dysregulated in pre-ataxic subjects compared to controls, displaying a combined discriminatory ability of 79%. In patients, ataxia severity was associated with higher levels of MEG3 and TSPOAP1. We propose expression levels of SAFB2, SFSWAP and LTBP4 as well as MEG3 and TSPOAP1 as stratification markers of SCA3/MJD progression, deserving further validation in longitudinal studies and in independent cohorts.


Assuntos
Doença de Machado-Joseph , Ataxias Espinocerebelares , Humanos , Doença de Machado-Joseph/genética , Transcriptoma , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/complicações , Ataxina-3/genética , Biomarcadores , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas dos Microfilamentos/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética
16.
J Biochem Mol Toxicol ; 38(2): e23644, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38348714

RESUMO

The nonalcoholic fatty liver disease (NAFLD), which is closely related to westernized dietary (WD) patterns, displays a rising epidemiological and economic burden. Since there is no pharmacological therapy approved for this disease, mechanistic studies are warranted. In this work, we investigated the action of carnosine (CAR), a natural dipeptide with several protection roles against oxidative stress in the liver of NAFLD rats. NAFLD was induced by WD-rich sugars and fat, verifying the histological evidence of steatosis. As intraperitoneal administration of CAR reversed liver steatosis, the protein profiles of NAFLD liver and CAR NAFLD liver were evaluated by label-free proteomics approach. A total of 2531 proteins were identified and the 230 and 276 were significantly up- and downregulated, respectively, by CAR treatment of NAFLD rats and involved in fundamental pathways such as oxidative stress and lipid metabolism. Perilipin 2 and apolipoprotein E, components of the plasma membrane of vesicle, resulted in highly downregulated in the CAR-treated NAFLD liver. The advanced bioanalytical approach demonstrated the efficacy of CAR in overcoming the main symptoms of NAFLD, ameliorating the steatosis in the liver.


Assuntos
Carnosina , Hepatopatia Gordurosa não Alcoólica , Humanos , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Carnosina/farmacologia , Carnosina/uso terapêutico , Dieta Ocidental/efeitos adversos , Proteômica/métodos , Fígado/metabolismo , Modelos Animais , Dieta Hiperlipídica , Metabolismo dos Lipídeos , Modelos Animais de Doenças
17.
J Phys Chem A ; 128(23): 4674-4684, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38815182

RESUMO

This work presents a comprehensive study exploring the thermodynamics of the solid phase of a series of phenylimidazoles, encompassing experimental measurements of heat capacity, volatility, and thermal behavior. The influence of successive phenyl group insertions on the imidazole ring on thermodynamic properties and supramolecular behavior was thoroughly examined through the evaluation of 2-phenylimidazole (2-PhI), 4-phenylimidazole (4-PhI), 4,5-diphenylimidazole (4,5-DPhI), and 2,4,5-triphenylimidazole (2,4,5-TPhI). Structural correlations between molecular structure and thermodynamic properties were established. Furthermore, the investigation employed UV-vis spectroscopy and quantum chemical calculations. Additive effects arising from the introduction of phenyl groups were found through the analysis of the solid-liquid and solid-gas equilibria, as well as heat capacities. A good correlation emerged between the thermodynamic properties of sublimation and the molar volume of the unit cell, evident across 2-PhI, 4,5-DPhI, and 2,4,5-TPhI. In contrast to its isomer 2-PhI, 4-PhI exhibited greater cohesive energy due to the stronger N-H···N intermolecular interactions, leading to the disruption of coplanar geometry in the 4-PhI molecules. The observed higher entropies of phase transition (fusion and sublimation) are consistent with the higher structural order observed in the crystalline lattice of 4-PhI.

18.
Nature ; 559(7714): 363-369, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29950727

RESUMO

Patients with prostate cancer frequently show resistance to androgen-deprivation therapy, a condition known as castration-resistant prostate cancer (CRPC). Acquiring a better understanding of the mechanisms that control the development of CRPC remains an unmet clinical need. The well-established dependency of cancer cells on the tumour microenvironment indicates that the microenvironment might control the emergence of CRPC. Here we identify IL-23 produced by myeloid-derived suppressor cells (MDSCs) as a driver of CRPC in mice and patients with CRPC. Mechanistically, IL-23 secreted by MDSCs can activate the androgen receptor pathway in prostate tumour cells, promoting cell survival and proliferation in androgen-deprived conditions. Intra-tumour MDSC infiltration and IL-23 concentration are increased in blood and tumour samples from patients with CRPC. Antibody-mediated inactivation of IL-23 restored sensitivity to androgen-deprivation therapy in mice. Taken together, these results reveal that MDSCs promote CRPC by acting in a non-cell autonomous manner. Treatments that block IL-23 can oppose MDSC-mediated resistance to castration in prostate cancer and synergize with standard therapies.


Assuntos
Interleucina-23/antagonistas & inibidores , Interleucina-23/metabolismo , Células Supressoras Mieloides/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/terapia , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Androgênios/deficiência , Animais , Benzamidas , Proliferação de Células , Sobrevivência Celular , Humanos , Interleucina-23/sangue , Interleucina-23/imunologia , Masculino , Camundongos , Células Supressoras Mieloides/citologia , Células Supressoras Mieloides/imunologia , Nitrilas , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Feniltioidantoína/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Receptores de Interleucina/metabolismo , Transdução de Sinais
19.
Dig Dis Sci ; 69(4): 1372-1379, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38353789

RESUMO

BACKGROUND: Delayed bleeding (DB) is a possible adverse event following gastric endoscopic submucosal dissection (ESD). The BEST-J score was created as a risk prediction model for DB following gastric ESD, but is yet to be validated in Western populations. AIMS: We aimed to validate the BEST-J score on a European sample and to perform a subgroup analysis according to histological classification. METHODS: Retrospective study of all consecutive patients undergoing gastric ESD on a European Endoscopic Unit. DB was defined as hemorrhage with clinical symptoms and confirmed by emergency endoscopy from the time of completion to 28 days after ESD. BEST-J score was calculated in each patient and confronted with the outcome (DB). RESULTS: Final sample included 161 patients. From these, 10 (6.2%) presented DB following ESD, with a median time to bleeding of 7 days (IQR 6.8). BEST-J score presented an excellent accuracy predicting DB in our sample, with an AUC = 0.907 (95%CI 0.801-1.000; p < 0.001). Subgroup analysis by histological classification proved that the discriminative power was still excellent for each grade: low-grade dysplasia-AUC = 0.970 (p < 0.001); high-grade dysplasia-AUC = 0.874 (p < 0.001); early gastric cancer-AUC = 0.881 (p < 0.001). The optimal cut-off value to predict DB was a BEST-J score ≥ 3, which matches the cut-off value for high-risk of bleeding in the original investigation. CONCLUSIONS: The BEST-J score still presents excellent accuracy in risk stratification for post-ESD bleeding in European individuals. Thus, this score may help to guide which patients benefit the most from prophylactic therapies following gastric ESD in this setting.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Humanos , Ressecção Endoscópica de Mucosa/efeitos adversos , Estudos Retrospectivos , Hemorragia Pós-Operatória/etiologia , Mucosa Gástrica/patologia , Fatores de Risco , Endoscopia Gastrointestinal , Neoplasias Gástricas/patologia
20.
BMC Pediatr ; 24(1): 446, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992610

RESUMO

BACKGROUND: The prevalence of complex chronic conditions (CCC), which cause serious limitations and require specialized care, is increasing. The diagnosis of a CCC is a health-illness transition for children and their parents, representing a long-term change leading to greater vulnerability. Knowing the characteristics of these transitional processes is important for promoting safe transitions in this population. This scoping review aimed to map the available evidence on health-illness transition processes in children with complex chronic conditions and their parents in the context of healthcare. METHODS: Six databases were searched for studies focusing on children aged 0-21 years with CCC and their parents experiencing health-illness transition processes, particularly concerning adaptation to illness and continuity of care, in the context of healthcare. Studies within this scope carried out between 2013 and 2023 and written in Portuguese or English were identified. The articles were selected using the PRISMA methodology. The data were extracted to an instrument and then presented with a synthesizing approach supporting the interpretation of the results. RESULTS: Ninety-eight methodologically broad but predominantly qualitative articles were included in this review. Children with CCC have specific needs associated with complex and dynamic health-illness transitions with a multiple influence in their daily lives. Several facilitating factors (p.e. positive communication and a supportive therapeutic relationship with parents and professionals, as well as involvement in a collaborative approach to care), inhibiting factors (p.e. the complexity of the disease and therapeutic regime, as well as the inefficient organization and coordination of teams) and both positive (p.e. well-being and better quality of life) and negative response patterns (p.e. negative feelings about the chronic illness) were identified. Some interventions to support the transitional process also emerged from the literature. Pediatric palliative care is seen as a good practice and an integrative approach for these children and families. CONCLUSION: Health professionals play a fundamental role in supporting the transitional process and promoting positive response patterns. More significant investment is needed at the clinical and academic levels regarding production and dissemination of knowledge in this area to ensure the awareness of children with CCC and that their needs are fully enhanced. REVIEW REGISTRATION: https://doi.org/10.17605/OSF.IO/QRZC8 .


Assuntos
Pais , Humanos , Criança , Doença Crônica/terapia , Pais/psicologia , Adolescente , Pré-Escolar , Adaptação Psicológica , Lactente , Adulto Jovem , Continuidade da Assistência ao Paciente , Transição Epidemiológica
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