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1.
Cell ; 178(4): 795-806.e12, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31398337

RESUMEN

Most patients diagnosed with resected pancreatic adenocarcinoma (PDAC) survive less than 5 years, but a minor subset survives longer. Here, we dissect the role of the tumor microbiota and the immune system in influencing long-term survival. Using 16S rRNA gene sequencing, we analyzed the tumor microbiome composition in PDAC patients with short-term survival (STS) and long-term survival (LTS). We found higher alpha-diversity in the tumor microbiome of LTS patients and identified an intra-tumoral microbiome signature (Pseudoxanthomonas-Streptomyces-Saccharopolyspora-Bacillus clausii) highly predictive of long-term survivorship in both discovery and validation cohorts. Through human-into-mice fecal microbiota transplantation (FMT) experiments from STS, LTS, or control donors, we were able to differentially modulate the tumor microbiome and affect tumor growth as well as tumor immune infiltration. Our study demonstrates that PDAC microbiome composition, which cross-talks to the gut microbiome, influences the host immune response and natural history of the disease.


Asunto(s)
Carcinoma Ductal Pancreático/microbiología , Carcinoma Ductal Pancreático/mortalidad , Microbioma Gastrointestinal , Neoplasias Pancreáticas/microbiología , Neoplasias Pancreáticas/mortalidad , Adulto , Anciano , Animales , Bacterias/clasificación , Línea Celular Tumoral , Estudios de Cohortes , Trasplante de Microbiota Fecal , Heces/microbiología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , ARN Ribosómico 16S/genética , Análisis de Secuencia de ARN , Tasa de Supervivencia
2.
Dev Dyn ; 252(8): 1077-1095, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36880501

RESUMEN

Neural crest cells (NCCs) are highly motile, multipotent, embryonic cells that delaminate from the dorsal edges of the neural tube. NCCs follow stereotypical long-range migratory pathways to reach target organs during development, where they give rise to multiple derivatives. The identification of reservoirs of neural crest stem cells that persist to adulthood has recently aroused renewed interest in the biology of NCCs. In this context, several recent studies have demonstrated the essential role of the metabolic kinase LKB1 in NCC establishment. This review surveys how LKB1 governs the formation and maintenance of several neural crest derivatives, including facial bones, melanocytes, Schwann cells, and the enteric nervous system. We also detail the underlying molecular mechanisms that involve downstream effectors of LKB1, in particular the contribution of the AMPK-mTOR signaling pathway to both polarity and metabolic processes. Collectively, these recent discoveries open promising perspectives for new therapeutic applications for the treatment of neural crest disorders.


Asunto(s)
Cresta Neural , Células-Madre Neurales , Cresta Neural/metabolismo , Transducción de Señal , Tubo Neural , Células de Schwann , Movimiento Celular/fisiología , Diferenciación Celular
3.
Br J Cancer ; 118(12): 1596-1608, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29795310

RESUMEN

BACKGROUND: While lung adenocarcinoma patients can somewhat benefit from anti-angiogenic therapies, patients with squamous cell lung carcinoma (SQLC) cannot. The reasons for this discrepancy remain largely unknown. Soluble VEGF receptor-1, namely sVEGFR1-i13, is a truncated splice variant of the cell membrane-spanning VEGFR1 that has no transmembrane or tyrosine kinase domain. sVEGFR1-i13 is mainly viewed as an anti-angiogenic factor which counteracts VEGF-A/VEGFR signalling in endothelial cells. However, its role in tumour cells is poorly known. METHODS: mRNA and protein status were analysed by Real-Time qPCR, western blotting, ELISA assay, proximity ligation assay or immunohistochemistry in human tumour cell lines, murine tumourgrafts and non small cell lung carcinoma patients samples. RESULTS: We show that anti-angiogenic therapies specifically increase the levels of sVEGFR1-i13 in SQLC cell lines and chemically induced SQLC murine tumourgrafts. At the molecular level, we characterise a sVEGFR1-i13/ß1 integrin/VEGFR autocrine loop which determines whether SQLC cells proliferate or go into apoptosis, in response to anti-angiogenic therapies. Furthermore, we show that high levels of both sVEGFR1-i13 and ß1 integrin mRNAs and proteins are associated with advanced stages in SQLC patients and with a poor clinical outcome in patients with early stage SQLC. CONCLUSIONS: Overall, these results reveal an unexpected pro-tumoural function of sVEGFR1-i13 in SQLC tumour cells, which contributes to their progression and escape from anti-angiogenic therapies. These data might help to understand why some SQLC patients do not respond to anti-angiogenic therapies.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Integrina beta1/metabolismo , Neoplasias Pulmonares/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Animales , Comunicación Autocrina/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/irrigación sanguínea , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/irrigación sanguínea , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/genética , Progresión de la Enfermedad , Humanos , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Ratones , Isoformas de Proteínas , Receptor Cross-Talk/efectos de los fármacos , Células Tumorales Cultivadas , Receptor 1 de Factores de Crecimiento Endotelial Vascular/genética , Ensayos Antitumor por Modelo de Xenoinjerto
5.
BMC Bioinformatics ; 15 Suppl 7: S4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25077573

RESUMEN

BACKGROUND: Currently available microRNA (miRNA) target prediction algorithms require the presence of a conserved seed match to the 5' end of the miRNA and limit the target sites to the 3' untranslated regions of mRNAs. However, it has been noted that these requirements may be too stringent, leading to a substantial number of missing targets. RESULTS: We have developed TargetS, a novel computational approach for predicting miRNA targets with the target sites located along entire gene sequences, which permits finding additional targets that are not located in the 3' un-translated regions. Our model is based on both canonical seed matching and non-canonical seed pairing, which discovers targets that allow one bit GU wobble. It does not rely on evolutionary conservation, so it allows the detection of species-specific miRNA-mRNA interactions and makes it suitable for analyzing un-conserved gene sequences. To test the performance of our approach, we have imported the widely used benchmark dataset revealing fold-changes in protein production corresponding to each of the five selected microRNAs. Compared to well-known miRNA target prediction tools, including TargetScanS, PicTar and MicroT_CDS, our method yields the highest sensitivity, while achieving a comparable level of accuracy. Human miRNA target predictions using our computational approach are available online at http://liubioinfolab.org/targetS/mirna.html CONCLUSIONS: A simple but powerful computational miRNA target prediction method is developed that is solely based on canonical and non-canonical seed matches without requiring evolutionary conservation of the target sites. Our method also expands the target search space to different gene regions, rather than limiting to 3'UTR only. This improves the sensitivity of miRNA target identification, while achieving a comparable accuracy with existing methods.


Asunto(s)
Genómica/métodos , MicroARNs/metabolismo , ARN Mensajero/genética , Algoritmos , Humanos , MicroARNs/química , MicroARNs/genética , Biosíntesis de Proteínas , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/química , ARN Mensajero/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos
6.
Antimicrob Agents Chemother ; 58(8): 4915-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24867973

RESUMEN

Sterile alpha motif- and histidine/aspartic acid domain-containing protein 1 (SAMHD1) limits HIV-1 replication by hydrolyzing deoxynucleoside triphosphates (dNTPs) necessary for reverse transcription. Nucleoside reverse transcriptase inhibitors (NRTIs) are components of anti-HIV therapies. We report here that SAMHD1 cleaves NRTI triphosphates (TPs) at significantly lower rates than dNTPs and that SAMHD1 depletion from monocytic cells affects the susceptibility of HIV-1 infections to NRTIs in complex ways that depend not only on the relative changes in dNTP and NRTI-TP concentrations but also on the NRTI activation pathways.


Asunto(s)
Didesoxinucleótidos/metabolismo , Transcriptasa Inversa del VIH/antagonistas & inhibidores , VIH-1/efectos de los fármacos , Proteínas de Unión al GTP Monoméricas/metabolismo , Inhibidores de la Transcriptasa Inversa/farmacología , Adenina/análogos & derivados , Adenina/farmacología , Línea Celular , Expresión Génica , Genes Reporteros , Transcriptasa Inversa del VIH/genética , Transcriptasa Inversa del VIH/metabolismo , VIH-1/enzimología , Interacciones Huésped-Patógeno , Humanos , Lamivudine/farmacología , Luciferasas/genética , Luciferasas/metabolismo , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Monocitos/virología , Proteínas de Unión al GTP Monoméricas/antagonistas & inhibidores , Proteínas de Unión al GTP Monoméricas/genética , Organofosfonatos/farmacología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteína 1 que Contiene Dominios SAM y HD , Estavudina/farmacología , Tenofovir , Replicación Viral/efectos de los fármacos , Zidovudina/farmacología
7.
Hepatology ; 58(6): 1941-52, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23703580

RESUMEN

UNLABELLED: Nonalcoholic fatty liver disease (NAFLD) covers a spectrum of liver damage ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. To date, no pharmacological treatment is approved for NAFLD/NASH. Here, we report on preclinical and clinical data with GFT505, a novel dual peroxisome proliferator-activated receptor alpha/delta (PPAR-α/δ) agonist. In the rat, GFT505 concentrated in the liver with limited extrahepatic exposure and underwent extensive enterohepatic cycling. The efficacy of GFT505 was assessed in animal models of NAFLD/NASH and liver fibrosis (Western diet [WD]-fed human apolipoprotein E2 [hApoE2] transgenic mice, methionine- and choline-deficient diet-fed db/db mice, and CCl4 -induced fibrosis in rats). GFT505 demonstrated liver-protective effects on steatosis, inflammation, and fibrosis. In addition, GFT505 improved liver dysfunction markers, decreased hepatic lipid accumulation, and inhibited proinflammatory (interleukin-1 beta, tumor necrosis factor alpha, and F4/80) and profibrotic (transforming growth factor beta, tissue inhibitor of metalloproteinase 2, collagen type I, alpha 1, and collagen type I, alpha 2) gene expression. To determine the role of PPAR-α-independent mechanisms, the effect of GFT505 was assessed in hApoE2 knock-in/PPAR-α knockout mice. In these mice, GFT505 also prevented WD-induced liver steatosis and inflammation, indicating a contribution of PPAR-α-independent mechanisms. Finally, the effect of GFT505 on liver dysfunction markers was assessed in a combined analysis of four phase II clinical studies in metabolic syndrome patients. GFT505 treatment decreased plasma concentrations of alanine aminotransferase, gamma-glutamyl transpeptidase, and alkaline phosphatase. CONCLUSION: The dual PPAR-α/δ agonist, GFT505, is a promising liver-targeted drug for treatment of NAFLD/NASH. In animals, its protective effects are mediated by both PPAR-α-dependent and -independent mechanisms.


Asunto(s)
Chalconas/uso terapéutico , Hígado Graso/tratamiento farmacológico , PPAR alfa/agonistas , PPAR delta/agonistas , Propionatos/uso terapéutico , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Animales , Intoxicación por Tetracloruro de Carbono/tratamiento farmacológico , Dislipidemias/tratamiento farmacológico , Hígado Graso/prevención & control , Humanos , Hígado/efectos de los fármacos , Cirrosis Hepática/prevención & control , Ratones , Enfermedad del Hígado Graso no Alcohólico , PPAR alfa/uso terapéutico , PPAR delta/uso terapéutico , Ratas
8.
World J Radiol ; 16(1): 1-8, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38312349

RESUMEN

Anti-N-methyl-D-aspartate receptor-associated encephalitis (NMDARE) is a rare immune-mediated neuroinflammatory condition characterized by the rapid onset of neuropsychiatric symptoms and autonomic dysfunction. The mechanism of pathogenesis remains incompletely understood, but is thought to be related to antibodies targeting the GluN1 subunit of the NMDA receptor with resultant downstream dysregulation of dopaminergic pathways. Young adults are most frequently affected; the median age at diagnosis is 21 years. There is a strong female predilection with a female sex predominance of 4:1. NMDARE often develops as a paraneoplastic process and is most commonly associated with ovarian teratoma. However, NMDARE has also been described in patients with small cell lung cancer, clear cell renal carcinoma, and other benign and malignant neoplasms. Diagnosis is based on correlation of the clinical presentation, electroencephalography, laboratory studies, and imaging. Computed tomography, positron emission tomography, and magnetic resonance imaging are essential to identify an underlying tumor, exclude clinicopathologic mimics, and predict the likelihood of long-term functional impairment. Nuclear imaging may be of value for prognostication and to assess the response to therapy. Treatment may involve high-dose corticosteroids, intravenous immunoglobulin, and plasma exchange. Herein, we review the hallmark clinicopathologic features and imaging findings of this rare but potentially devastating condition and summarize diagnostic criteria, treatment regimens, and proposed pathogenetic mechanisms.

9.
J Ren Care ; 49(4): 278-287, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36210458

RESUMEN

BACKGROUND: Nurse practitioners (NP) have an expanded scope of practice beyond that of a registered nurse. In kidney care, nephrology NP can manage patients at various points along the chronic kidney disease (CKD) trajectory. OBJECTIVES: To profile the characteristics, service patterns, and domains of practice of nephrology NP in Australia. DESIGN: A cross-sectional online secure survey. PARTICIPANTS: Nephrology NP (NP students) who were members of the Renal Society of Australasia and working in Australia (n = 73). MEASUREMENTS: Data collected were demographic and practice characteristics, and domains of practice (using the modified Strong Model of Advanced Practice). The survey also sought qualitative perspectives of the enablers and barriers to sustainability nurse practitioner healthcare delivery services. RESULTS: Nephrology NP (n = 45) primarily worked in adult services, managing those receiving haemodialysis, peritoneal dialysis, or patients with earlier grades of CKD. Providing direct comprehensive care was the dominant domain of advanced practice although administrative activities took up considerable time each week. Support from nurse leaders and medical colleagues was identified as key enablers for sustainability of these services whereas succession planning, and workload were the main barriers. CONCLUSIONS: This study found a highly qualified, experienced but older nephrology nurse practitioner workforce who provide an additional model of health service delivery which can meet the growing CKD burden. Internationally, this level of nurse provides an opportunity for a career pathway to maintain nurses in direct clinical roles and to expand the nephrology nursing workforce.


Asunto(s)
Nefrología , Enfermeras Practicantes , Insuficiencia Renal Crónica , Adulto , Humanos , Estudios Transversales , Australia , Insuficiencia Renal Crónica/terapia , Rol de la Enfermera
10.
J Med Chem ; 65(24): 16290-16312, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36469401

RESUMEN

Dual leucine zipper kinase (DLK) and leucine zipper-bearing kinase (LZK) are regulators of neuronal degeneration and axon growth. Therefore, there is a considerable interest in developing DLK/LZK inhibitors for neurodegenerative diseases. Herein, we use ligand- and structure-based drug design approaches for identifying novel amino-pyrazine inhibitors of DLK/LZK. DN-1289 (14), a potent and selective dual DLK/LZK inhibitor, demonstrated excellent in vivo plasma half-life across species and is anticipated to freely penetrate the central nervous system with no brain impairment based on in vivo rodent pharmacokinetic studies and human in vitro transporter data. Proximal target engagement and disease relevant pathway biomarkers were also favorably regulated in an in vivo model of amyotrophic lateral sclerosis.


Asunto(s)
Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Humanos , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/metabolismo , Leucina Zippers , Quinasas Quinasa Quinasa PAM , Sistema Nervioso Central/metabolismo , Encéfalo/metabolismo , Enfermedades Neurodegenerativas/metabolismo
11.
J Biol Chem ; 285(47): 36759-67, 2010 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-20851881

RESUMEN

The bile acid receptor farnesoid X receptor (FXR) is expressed in adipose tissue, but its function remains poorly defined. Peroxisome proliferator-activated receptor-γ (PPARγ) is a master regulator of adipocyte differentiation and function. The aim of this study was to analyze the role of FXR in adipocyte function and to assess whether it modulates PPARγ action. Therefore, we tested the responsiveness of FXR-deficient mice (FXR(-/-)) and cells to the PPARγ activator rosiglitazone. Our results show that genetically obese FXR(-/-)/ob/ob mice displayed a resistance to rosiglitazone treatment. In vitro, rosiglitazone treatment did not induce normal adipocyte differentiation and lipid droplet formation in FXR(-/-) mouse embryonic fibroblasts (MEFs) and preadipocytes. Moreover, FXR(-/-) MEFs displayed both an increased lipolysis and a decreased de novo lipogenesis, resulting in reduced intracellular triglyceride content, even upon PPARγ activation. Retroviral-mediated FXR re-expression in FXR(-/-) MEFs restored the induction of adipogenic marker genes during rosiglitazone-forced adipocyte differentiation. The expression of Wnt/ß-catenin pathway and target genes was increased in FXR(-/-) adipose tissue and MEFs. Moreover, the expression of several endogenous inhibitors of this pathway was decreased early during the adipocyte differentiation of FXR(-/-) MEFs. These findings demonstrate that FXR regulates adipocyte differentiation and function by regulating two counteracting pathways of adipocyte differentiation, the PPARγ and Wnt/ß-catenin pathways.


Asunto(s)
Adipocitos/citología , Diferenciación Celular , PPAR gamma/metabolismo , Receptores Citoplasmáticos y Nucleares/fisiología , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Animales , Biomarcadores/metabolismo , Western Blotting , Células Cultivadas , Resistencia a Medicamentos , Embrión de Mamíferos/citología , Embrión de Mamíferos/efectos de los fármacos , Embrión de Mamíferos/metabolismo , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Proteína-1 Reguladora de Fusión , Perfilación de la Expresión Génica , Humanos , Hipoglucemiantes/farmacología , Riñón/citología , Riñón/efectos de los fármacos , Riñón/metabolismo , Lipólisis , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Obesos , Análisis de Secuencia por Matrices de Oligonucleótidos , PPAR gamma/genética , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rosiglitazona , Transducción de Señal , Tiazolidinedionas/farmacología , Proteínas Wnt/genética , beta Catenina/genética
12.
J Immunother Cancer ; 9(12)2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34916256

RESUMEN

BACKGROUND: Glypican-3 (GPC-3) is an oncofetal protein that is highly expressed in various solid tumors, but rarely expressed in healthy adult tissues and represents a rational target of particular relevance in hepatocellular carcinoma (HCC). Autologous chimeric antigen receptor (CAR) αß T cell therapies have established significant clinical benefit in hematologic malignancies, although efficacy in solid tumors has been limited due to several challenges including T cell homing, target antigen heterogeneity, and immunosuppressive tumor microenvironments. Gamma delta (γδ) T cells are highly cytolytic effectors that can recognize and kill tumor cells through major histocompatibility complex (MHC)-independent antigens upregulated under stress. The Vδ1 subset is preferentially localized in peripheral tissue and engineering with CARs to further enhance intrinsic antitumor activity represents an attractive approach to overcome challenges for conventional T cell therapies in solid tumors. Allogeneic Vδ1 CAR T cell therapy may also overcome other hurdles faced by allogeneic αß T cell therapy, including graft-versus-host disease (GvHD). METHODS: We developed the first example of allogeneic CAR Vδ1 T cells that have been expanded from peripheral blood mononuclear cells (PBMCs) and genetically modified to express a 4-1BB/CD3z CAR against GPC-3. The CAR construct (GPC-3.CAR/secreted interleukin-15 (sIL)-15) additionally encodes a constitutively-secreted form of IL-15, which we hypothesized could sustain proliferation and antitumor activity of intratumoral Vδ1 T cells expressing GPC-3.CAR. RESULTS: GPC-3.CAR/sIL-15 Vδ1 T cells expanded from PBMCs on average 20,000-fold and routinely reached >80% purity. Expanded Vδ1 T cells showed a primarily naïve-like memory phenotype with limited exhaustion marker expression and displayed robust in vitro proliferation, cytokine production, and cytotoxic activity against HCC cell lines expressing low (PLC/PRF/5) and high (HepG2) GPC-3 levels. In a subcutaneous HepG2 mouse model in immunodeficient NSG mice, GPC-3.CAR/sIL-15 Vδ1 T cells primarily accumulated and proliferated in the tumor, and a single dose efficiently controlled tumor growth without evidence of xenogeneic GvHD. Importantly, compared with GPC-3.CAR Vδ1 T cells lacking sIL-15, GPC-3.CAR/sIL-15 Vδ1 T cells displayed greater proliferation and resulted in enhanced therapeutic activity. CONCLUSIONS: Expanded Vδ1 T cells engineered with a GPC-3 CAR and sIL-15 represent a promising platform warranting further clinical evaluation as an off-the-shelf treatment of HCC and potentially other GPC-3-expressing solid tumors.


Asunto(s)
Carcinoma Hepatocelular/terapia , Glipicanos/inmunología , Inmunoterapia Adoptiva/métodos , Interleucina-15/inmunología , Neoplasias Hepáticas/terapia , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Receptores Quiméricos de Antígenos/inmunología , Animales , Apoptosis , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Proliferación Celular , Femenino , Humanos , Leucocitos Mononucleares , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Neuron ; 105(5): 837-854.e9, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-31902528

RESUMEN

Loss-of-function (LOF) variants of TREM2, an immune receptor expressed in microglia, increase Alzheimer's disease risk. TREM2 senses lipids and mediates myelin phagocytosis, but its role in microglial lipid metabolism is unknown. Combining chronic demyelination paradigms and cell sorting with RNA sequencing and lipidomics, we find that wild-type microglia acquire a disease-associated transcriptional state, while TREM2-deficient microglia remain largely homeostatic, leading to neuronal damage. TREM2-deficient microglia phagocytose myelin debris but fail to clear myelin cholesterol, resulting in cholesteryl ester (CE) accumulation. CE increase is also observed in APOE-deficient glial cells, reflecting impaired brain cholesterol transport. This finding replicates in myelin-treated TREM2-deficient murine macrophages and human iPSC-derived microglia, where it is rescued by an ACAT1 inhibitor and LXR agonist. Our studies identify TREM2 as a key transcriptional regulator of cholesterol transport and metabolism under conditions of chronic myelin phagocytic activity, as TREM2 LOF causes pathogenic lipid accumulation in microglia.


Asunto(s)
Encéfalo/metabolismo , Colesterol/metabolismo , Macrófagos/metabolismo , Glicoproteínas de Membrana/genética , Microglía/metabolismo , Vaina de Mielina/metabolismo , Fagocitosis/genética , Receptores Inmunológicos/genética , Acetil-CoA C-Acetiltransferasa/antagonistas & inhibidores , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Animales , Ésteres del Colesterol/metabolismo , Modelos Animales de Enfermedad , Citometría de Flujo , Humanos , Células Madre Pluripotentes Inducidas , Metabolismo de los Lípidos/genética , Lipidómica , Receptores X del Hígado/agonistas , Ratones , Ratones Noqueados , Ratones Noqueados para ApoE , RNA-Seq
14.
Genome Biol ; 21(1): 271, 2020 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-33148332

RESUMEN

BACKGROUND: Metastasis is the primary cause of cancer mortality accounting for 90% of cancer deaths. Our understanding of the molecular mechanisms driving metastasis is rudimentary. RESULTS: We perform whole exome sequencing (WES), RNA sequencing, methylation microarray, and immunohistochemistry (IHC) on 8 pairs of non-small cell lung cancer (NSCLC) primary tumors and matched distant metastases. Furthermore, we analyze published WES data from 35 primary NSCLC and metastasis pairs, and transcriptomic data from 4 autopsy cases with metastatic NSCLC and one metastatic lung cancer mouse model. The majority of somatic mutations are shared between primary tumors and paired distant metastases although mutational signatures suggest different mutagenesis processes in play before and after metastatic spread. Subclonal analysis reveals evidence of monoclonal seeding in 41 of 42 patients. Pathway analysis of transcriptomic data reveals that downregulated pathways in metastases are mainly immune-related. Further deconvolution analysis reveals significantly lower infiltration of various immune cell types in metastases with the exception of CD4+ T cells and M2 macrophages. These results are in line with lower densities of immune cells and higher CD4/CD8 ratios in metastases shown by IHC. Analysis of transcriptomic data from autopsy cases and animal models confirms that immunosuppression is also present in extracranial metastases. Significantly higher somatic copy number aberration and allelic imbalance burdens are identified in metastases. CONCLUSIONS: Metastasis is a molecularly late event, and immunosuppression driven by different molecular events, including somatic copy number aberration, may be a common characteristic of tumors with metastatic plasticity.


Asunto(s)
Terapia de Inmunosupresión , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Metástasis de la Neoplasia/genética , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Metilación de ADN , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica , Genómica , Humanos , Inmunohistoquímica , Ratones , Mutación , Transcriptoma , Secuenciación del Exoma
15.
Sci Adv ; 5(7): eaau5106, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31328154

RESUMEN

Metabolic processes underlying the development of the neural crest, an embryonic population of multipotent migratory cells, are poorly understood. Here, we report that conditional ablation of the Lkb1 tumor suppressor kinase in mouse neural crest stem cells led to intestinal pseudo-obstruction and hind limb paralysis. This phenotype originated from a postnatal degeneration of the enteric nervous ganglia and from a defective differentiation of Schwann cells. Metabolomic profiling revealed that pyruvate-alanine conversion is enhanced in the absence of Lkb1. Mechanistically, inhibition of alanine transaminases restored glial differentiation in an mTOR-dependent manner, while increased alanine level directly inhibited the glial commitment of neural crest cells. Treatment with the metabolic modulator AICAR suppressed mTOR signaling and prevented Schwann cell and enteric defects of Lkb1 mutant mice. These data uncover a link between pyruvate-alanine cycling and the specification of glial cell fate with potential implications in the understanding of the molecular pathogenesis of neural crest diseases.


Asunto(s)
Alanina/metabolismo , Cresta Neural/citología , Cresta Neural/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Ácido Pirúvico/metabolismo , Proteínas Quinasas Activadas por AMP , Animales , Diferenciación Celular/genética , Metabolismo Energético , Sistema Nervioso Entérico , Silenciador del Gen , Melanocitos/metabolismo , Ratones , Ratones Noqueados , Mitocondrias/metabolismo , Degeneración Nerviosa/etiología , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/patología , Neuroglía/citología , Neuroglía/metabolismo , Enfermedades del Sistema Nervioso Periférico/etiología , Enfermedades del Sistema Nervioso Periférico/metabolismo , Enfermedades del Sistema Nervioso Periférico/patología , Fenotipo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal
16.
J Nutr ; 138(10): 1915-22, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18806101

RESUMEN

The crossover relationship between cardiometabolic risk, in terms of insulin resistance and vascular dysfunction, and the fatty acid (FA) profile of insulin-sensitive tissues as well as the dietary FA impact has almost never been explored in the same experiment. In this study, the intake of alpha-linolenic acid (ALA) alone and/or with its higher metabolites, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were evaluated in a nonobese, hypertriglyceridemic and insulin-resistant rat model, that exhibits the 2 main characteristics of metabolic syndrome. Wistar rats were fed either a cornstarch and (n-6) PUFA-based diet (C-N6) or a 66% fructose diet over a 10-wk period. Fructose-fed rats received a diet containing ALA alone (F-ALA group) or ALA plus EPA and DHA (F-LC3 group) or no (n-3) PUFA (F-N6 group). The 10-wk high-fructose diet (F-N6) induced an insulin-resistant state, as assessed by glucose and insulin tolerance tests. Insulin resistance was linked to a specific FA pattern in insulin-sensitive tissues, which probably involved modifications of Delta9, Delta6, and Delta5-desaturases. This pathological status was related to high cardiovascular risk as assessed by increases in systolic and diastolic blood pressures and particularly by the increase of pulse pressure, an index of vascular stiffness obtained from telemetry investigations. The (n-3) experimental diets prevented changes in the FA patterns in insulin-sensitive tissues, insulin resistance, and vascular dysfunction. This beneficial effect was large with an intake of long chain (n-3) PUFA (ALA+EPA+DHA) and to a lesser extent with dietary ALA alone.


Asunto(s)
Carbohidratos de la Dieta , Ácidos Grasos Omega-3/farmacología , Fructosa , Enfermedades Metabólicas/prevención & control , Enfermedades Vasculares/prevención & control , Animales , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Ácidos Grasos Omega-3/uso terapéutico , Prueba de Tolerancia a la Glucosa , Insulina/sangre , Insulina/metabolismo , Insulina/farmacología , Resistencia a la Insulina , Secreción de Insulina , Masculino , Modelos Animales , Ratas , Ratas Wistar , Sístole/efectos de los fármacos
17.
Metabolism ; 57(2): 233-40, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18191054

RESUMEN

This study investigated the influence of an eicosapentaenoic acid (EPA)- or a docosahexaenoic acid (DHA)-supplemented diet on the deleterious effects of lysophosphatidylcholine (LPC) on endothelium-dependent vasorelaxation of Golden Syrian hamster thoracic aorta. In a second step, LPC-modulated phospholipase A(2) (PLA(2))-derived ways of relaxation were investigated. Golden Syrian hamsters were fed for 6 weeks with a control diet or an EPA- or DHA-supplemented diet. Aortic fatty acid composition was analyzed by gas chromatography. Aortic rings were incubated for 20 minutes with LPC before constructing cumulative concentration-response curves for acetylcholine (ACh; 3 nmol/L-30 micromol/L) or sodium nitroprusside (3 nmol/L-30 micromol/L). The EPA- or DHA-supplemented diet increased n-3 polyunsaturated fatty acids in aortic fatty acids content because of the increase of EPA or DHA content, respectively, and decreased arachidonic acid aortic content. Lysophosphatidylcholine (1, 10, 15, and 20 micromol/L) induced a concentration-dependent inhibition of ACh-induced relaxation of preconstricted aortic rings in the control group, but did not influence sodium nitroprusside-induced aortic relaxation. The DHA- or EPA-supplemented diet worsened LPC (20 micromol/L) inhibitory effects on ACh-induced vasorelaxation. In the control diet group, ACh-induced relaxation was abolished by the nitric oxide synthase inhibitor (l-N(G)-nitro-arginine methyl ester; 100 micromol/L), whether LPC was added or not. The ACh-induced vasorelaxation was partially inhibited by PLA(2) inhibitors methyl arachidonyl fluorophosphonate (25 micromol/L) and arachidonyl trifluoromethyl ketone (20 micromol/L) as well as by the combination of 2 Ca(2+)-dependent potassium (K(Ca)) channel inhibitors charybdotoxin (0.1 micromol/L) plus apamin (0.3 micromol/L). In the presence of LPC (20 micromol/L), ACh-induced vasorelaxation was abolished by these inhibitors. These effects were not influenced by DHA or EPA diet. Our results suggested that EPA- or DHA-supplemented diet did not exhibit any beneficial effect against LPC-induced inhibition of endothelium-dependent aortic relaxation in Golden Syrian hamsters. These LPC effects were associated in our study not only with an inhibition of nitric oxide-dependent vasorelaxation, but also with a concomitant activation of a compensatory vasorelaxant pathway depending both on PLA(2) metabolites and on K(Ca) channel opening.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Ácidos Grasos Omega-3/administración & dosificación , Lisofosfatidilcolinas/administración & dosificación , Acetilcolina/farmacología , Animales , Aorta Torácica , Cricetinae , Suplementos Dietéticos , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiología , Inhibidores Enzimáticos/farmacología , Técnicas In Vitro , Mesocricetus , Relajación Muscular/efectos de los fármacos , Relajación Muscular/fisiología , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/metabolismo , Nitroprusiato/farmacología , Inhibidores de Fosfolipasa A2 , Fosfolipasas A2/metabolismo , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio/metabolismo , Distribución Aleatoria
18.
Oncotarget ; 9(19): 14764-14790, 2018 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-29599906

RESUMEN

This manuscript follows a single patient with pancreatic adenocarcinoma for a five year period, detailing the clinical record, pathology, the dynamic evolution of molecular and cellular alterations as well as the responses to treatments with chemotherapies, targeted therapies and immunotherapies. DNA and RNA samples from biopsies and blood identified a dynamic set of changes in allelic imbalances and copy number variations in response to therapies. Organoid cultures established from biopsies over time were employed for extensive drug testing to determine if this approach was feasible for treatments. When an unusual drug response was detected, an extensive RNA sequencing analysis was employed to establish novel mechanisms of action of this drug. Organoid cell cultures were employed to identify possible antigens associated with the tumor and the patient's T-cells were expanded against one of these antigens. Similar and identical T-cell receptor sequences were observed in the initial biopsy and the expanded T-cell population. Immunotherapy treatment failed to shrink the tumor, which had undergone an epithelial to mesenchymal transition prior to therapy. A warm autopsy of the metastatic lung tumor permitted an extensive analysis of tumor heterogeneity over five years of treatment and surgery. This detailed analysis of the clinical descriptions, imaging, pathology, molecular and cellular evolution of the tumors, treatments, and responses to chemotherapy, targeted therapies, and immunotherapies, as well as attempts at the development of personalized medical treatments for a single patient should provide a valuable guide to future directions in cancer treatment.

19.
Psychiatr Serv ; 66(2): 112-4, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25642607

RESUMEN

Clinical evidence-based practices are strongly encouraged and commonly utilized in the behavioral health community. However, evidence-based practices that are related to quality improvement processes, such as Design for Six Sigma, are often not used in behavioral health care. This column describes the unique partnership formed between a behavioral health care provider in the greater Pittsburgh area, a nonprofit oversight and monitoring agency for behavioral health services, and academic researchers. The authors detail how the partnership used the multistep process outlined in Design for Six Sigma to completely redesign the provider's intake process. Implementation of the redesigned process increased access to care, decreased bad debt and uncollected funds, and improved cash flow--while consumer satisfaction remained high.


Asunto(s)
Conducta Cooperativa , Práctica Clínica Basada en la Evidencia/organización & administración , Servicios de Salud Mental/organización & administración , Organizaciones sin Fines de Lucro/organización & administración , Calidad de la Atención de Salud/organización & administración , Práctica Clínica Basada en la Evidencia/normas , Accesibilidad a los Servicios de Salud , Humanos , Servicios de Salud Mental/normas , Organizaciones sin Fines de Lucro/normas , Calidad de la Atención de Salud/normas , Universidades
20.
J Pharm Pharmacol ; 55(5): 639-46, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12831506

RESUMEN

This study examines the potential for the phytoestrogenic isoflavones, a type of complementary medicine, to be involved in pharmacokinetic interactions in the liver. Rat livers were isolated and perfused to steady state, in single-pass mode, with either 5 microM paracetamol (n = 6), or 5 microM paracetamol with a 50:50 molar mixture of genistein and biochanin A or daidzein and formononetin, at a total isoflavone concentration of 1 and 10 microM (n = 6 for each mixture at each concentration). At 1 microM, neither isoflavone mixture had any effect, while at 10 microM both mixtures decreased the clearance of paracetamol and the formation clearance to paracetamol sulfate. Genistein and biochanin A (10 microM) also increased the biliary extraction of hepatically-generated paracetamol sulfate. Additional livers were perfused with an infusion of 5 microM (14)C-paracetamol in the absence (n = 4), or presence, of a 10 microM genistein and biochanin A mixture (n = 4). Analysis of washout perfusate and bile samples (up to 30 min after stopping the infusion) revealed that the isoflavones reduced the first-order rate constant for paracetamol sulfate transport into perfusate, but not for transport into bile. The results indicate that isoflavones can reduce the formation of paracetamol sulfate and that its enhanced excretion into bile arises from the inhibition of sinusoidal efflux transport.


Asunto(s)
Acetaminofén/análogos & derivados , Acetaminofén/metabolismo , Estrógenos no Esteroides/farmacocinética , Isoflavonas/farmacocinética , Hígado/metabolismo , Animales , Estrógenos no Esteroides/farmacología , Isoflavonas/farmacología , Hígado/efectos de los fármacos , Masculino , Perfusión/métodos , Fitoestrógenos , Preparaciones de Plantas , Ratas , Ratas Sprague-Dawley
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