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OBJECTIVE: Mitochondrial ATP-sensitive K+ (mitoKATP) channels are involved in neuronal and cardiac protection from ischemia and oxidative stress. Penile erection is a neurovascular event mediated by relaxation of the erectile tissue via nitric oxide (NO) released from nerves and endothelium. In the present study, we investigated whether mitoKATP channels play a role in the control of penile vascular tone and mitochondrial dynamics, and the involvement of NO. METHODS: The effect of the selective mitoKATP activator BMS191095 was examined on vascular tone, on mitochondrial bioenergetics by real-time measurements with Agilent Seahorse and on ROS production by MitoSOX fluorescence in freshly isolated microarteries. RESULTS: BMS191095 and diazoxide relaxed penile arteries, BMS191095 being one order of magnitude more potent. BMS191095-induced relaxations were reduced by mechanical endothelium removal and by inhibitors of the nitric oxide synthase (NOS) and PI3K enzymes. The NO-dependent component of the relaxation to BMS191095 was impaired in penile arteries from insulin resistant obese rats. The blockers of mitoKATP channel 5-HD, sarcolemma KATP (sarcKATP) channel glibenclamide, and large conductance Ca2+-activated K+ (BKCa) channel iberiotoxin, inhibited relaxations to BMS191095 and to the NO donor SNAP. BMS191095 reduced the mitochondrial bioenergetic profile of penile arteries and attenuated mitochondrial ROS production. Blockade of endogenous NO impaired and exogenous NO mimicked, respectively, the inhibitory effects of BMS191095 on basal respiration and oxygen consumed for ATP synthesis. Exogenous NO exhibited dual inhibitory/stimulatory effects on mitochondrial respiration. CONCLUSIONS: These results demonstrate that selective activation of mitoKATP channels causes penile vasodilation, attenuates ROS production and inhibits mitochondrial respiration in part by releasing endothelial NO. These mechanisms couple blood flow and metabolism in penile arterial wall and suggest that activation of vascular mitoKATP channels may protect erectile tissue against ischemic injury.
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Óxido Nítrico , Canais de Potássio , Vasodilatação , Masculino , Ratos , Animais , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trifosfato de Adenosina , RespiraçãoRESUMO
Chimeric antigen receptor T cells (CAR-Ts) have remarkable efficacy in liquid tumors, but limited responses in solid tumors. We conducted a Phase I trial (NCT02107963) of GD2 CAR-Ts (GD2-CAR.OX40.28.z.iC9), demonstrating feasibility and safety of administration in children and young adults with osteosarcoma and neuroblastoma. Since CAR-T efficacy requires adequate CAR-T expansion, patients were grouped into good or poor expanders across dose levels. Patient samples were evaluated by multi-dimensional proteomic, transcriptomic, and epigenetic analyses. T cell assessments identified naive T cells in pre-treatment apheresis associated with good expansion, and exhausted T cells in CAR-T products with poor expansion. Myeloid cell assessment identified CXCR3+ monocytes in pre-treatment apheresis associated with good expansion. Longitudinal analysis of post-treatment samples identified increased CXCR3- classical monocytes in all groups as CAR-T numbers waned. Together, our data uncover mediators of CAR-T biology and correlates of expansion that could be utilized to advance immunotherapies for solid tumor patients.
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Neuroblastoma , Receptores de Antígenos Quiméricos , Criança , Adulto Jovem , Humanos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos de Linfócitos T/genética , Proteômica , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Linfócitos T , Neuroblastoma/patologia , Terapia Baseada em Transplante de Células e TecidosRESUMO
A 76-year-old man with stage IV urothelial carcinoma who was receiving atezolizumab presented with dyspnea, elevated cardiac biomarkers, new negative T waves, and left ventricular apical akinesia. Coronary angiography results were normal. Immune checkpoint inhibitor-related myocarditis was suspected, and high-dose corticosteroid treatment was started. Cardiac magnetic resonance showed apical edema, suggesting stress cardiomyopathy. (Level of Difficulty: Beginner.).
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Doenças do Sistema Nervoso Autônomo , Hemangioma Cavernoso do Sistema Nervoso Central , Malformações do Sistema Nervoso , Humanos , Tronco Encefálico/diagnóstico por imagem , Doenças do Sistema Nervoso Autônomo/diagnóstico por imagem , Doenças do Sistema Nervoso Autônomo/etiologia , Pele , Hemangioma Cavernoso do Sistema Nervoso Central/complicações , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagemRESUMO
BACKGROUND: Strongyloidiasis is an underdiagnosed and preventable life-threatening disease caused by infection with the helminth Strongyloides stercoralis. Chronic asymptomatic infection can be sustained for decades, and immunosuppression can lead to disseminated infection, with a mortality rate of 70%-100%. In the neurosurgical population, corticosteroids are the most consistent cause of hyperinfection. OBSERVATIONS: The authors present the case of a 33-year-old woman of Paraguayan origin who was diagnosed with sphenoid planum meningioma and treated with a high dose of corticosteroids on the basis of the diagnosis. She underwent surgery, and pathological anatomy reflected grade I meningioma. After the surgery, she started with a history of dyspnea, productive cough, fever, and urticarial rash. Later, she presented with intestinal pseudo-obstruction and bacterial meningitis with hydrocephalus. Serology was positive for Strongyloides (enzyme-linked immunosorbent assay), and she was diagnosed with hyperinfection syndrome. Ivermectin 200 µg/kg daily was established. LESSONS: It may be of interest to rule out a chronic Strongyloides infection in patients from risk areas (immigrants or those returning from recent trips) before starting treatment with corticosteroids.
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Adenosine monophosphate-activated protein kinase (AMPK) is a cellular energy sensor activated during energy stress that plays a key role in maintaining energy homeostasis. This ubiquitous signaling pathway has been implicated in multiple functions including mitochondrial biogenesis, redox regulation, cell growth and proliferation, cell autophagy and inflammation. The protective role of AMPK in cardiovascular function and the involvement of dysfunctional AMPK in the pathogenesis of cardiovascular disease have been highlighted in recent years. In this review, we summarize and discuss the role of AMPK in the regulation of blood flow in response to metabolic demand and the basis of the AMPK physiological anticontractile, antioxidant, anti-inflammatory, and antiatherogenic actions in the vascular system. Investigations by others and us have demonstrated the key role of vascular AMPK in the regulation of endothelial function, redox homeostasis, and inflammation, in addition to its protective role in the hypoxia and ischemia/reperfusion injury. The pathophysiological implications of AMPK involvement in vascular function with regard to the vascular complications of metabolic disease and the therapeutic potential of AMPK activators are also discussed.
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Proteínas Quinases Ativadas por AMP/metabolismo , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Vasos Sanguíneos/metabolismo , Doenças Cardiovasculares/metabolismo , Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Doenças Metabólicas/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Monofosfato de Adenosina/metabolismo , Animais , Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Vasos Sanguíneos/patologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Regulação da Expressão Gênica , Glucose/metabolismo , Humanos , Hipóxia/genética , Hipóxia/patologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Metabolismo dos Lipídeos/genética , Doenças Metabólicas/genética , Doenças Metabólicas/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Estresse FisiológicoRESUMO
Metastasis is the leading cause of cancer-related deaths, and greater knowledge of the metastatic microenvironment is necessary to effectively target this process. Microenvironmental changes occur at distant sites prior to clinically detectable metastatic disease; however, the key niche regulatory signals during metastatic progression remain poorly characterized. Here, we identify a core immune suppression gene signature in pre-metastatic niche formation that is expressed predominantly by myeloid cells. We target this immune suppression program by utilizing genetically engineered myeloid cells (GEMys) to deliver IL-12 to modulate the metastatic microenvironment. Our data demonstrate that IL12-GEMy treatment reverses immune suppression in the pre-metastatic niche by activating antigen presentation and T cell activation, resulting in reduced metastatic and primary tumor burden and improved survival of tumor-bearing mice. We demonstrate that IL12-GEMys can functionally modulate the core program of immune suppression in the pre-metastatic niche to successfully rebalance the dysregulated metastatic microenvironment in cancer.
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Terapia de Imunossupressão , Células Mieloides/metabolismo , Imunidade Adaptativa , Animais , Linhagem Celular Tumoral , Engenharia Genética , Humanos , Interleucina-12/genética , Interleucina-12/metabolismo , Pulmão/metabolismo , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células Mieloides/citologia , Células Mieloides/imunologia , Metástase Neoplásica , Rabdomiossarcoma/metabolismo , Rabdomiossarcoma/patologia , Taxa de Sobrevida , Linfócitos T/imunologia , Linfócitos T/metabolismo , Microambiente TumoralRESUMO
Despite a remarkable increase in the genomic profiling of cancer, integration of genomic discoveries into clinical care has lagged behind. We report the feasibility of rapid identification of targetable mutations in 153 pediatric patients with relapsed/refractory or high-risk leukemias enrolled on a prospective clinical trial conducted by the LEAP Consortium. Eighteen percent of patients had a high confidence Tier 1 or 2 recommendation. We describe clinical responses in the 14% of patients with relapsed/refractory leukemia who received the matched targeted therapy. Further, in order to inform future targeted therapy for patients, we validated variants of uncertain significance, performed ex vivo drug-sensitivity testing in patient leukemia samples, and identified new combinations of targeted therapies in cell lines and patient-derived xenograft models. These data and our collaborative approach should inform the design of future precision medicine trials. SIGNIFICANCE: Patients with relapsed/refractory leukemias face limited treatment options. Systematic integration of precision medicine efforts can inform therapy. We report the feasibility of identifying targetable mutations in children with leukemia and describe correlative biology studies validating therapeutic hypotheses and novel mutations.See related commentary by Bornhauser and Bourquin, p. 1322.This article is highlighted in the In This Issue feature, p. 1307.
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Leucemia/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Biomarcadores Tumorais/genética , Criança , Estudos de Coortes , Progressão da Doença , Estudos de Viabilidade , Feminino , Humanos , Leucemia/genética , Leucemia/mortalidade , Masculino , Terapia de Alvo Molecular , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Estudos Prospectivos , Estados UnidosRESUMO
BACKGROUND: The treatment paradigm for patients with relapsed/refractory B-cell acute lymphoblastic leukemia (rrALL) has been revolutionized given recent clinical trials demonstrating remarkable success of immunotherapies and leading to drug approvals by United States and European agencies. We report experience with commercial blinatumomab and inotuzumab use at two North American pediatric oncology centers in children and adolescents/young adults with B-ALL. PROCEDURE: Patients 0-25 years old treated with the CD19 × CD3 bispecific T cell-engaging antibody blinatumomab and/or the CD22 antibody-drug conjugate inotuzumab from January 1, 2010, to June 1, 2018, were eligible. Disease status included relapsed B-ALL in second or greater relapse, primary chemotherapy-refractory B-ALL, or B-ALL complicated by severe infection precluding delivery of conventional chemotherapy. RESULTS: We identified 27 patients who received blinatumomab and/or inotuzumab outside of clinical trials during the study period. Four of the 13 patients (31%) with relapsed disease achieved minimal residual disease (MRD)-negative remission, and five patients (39%) underwent hematopoietic stem cell transplant (HSCT). In the 12 patients with primary chemorefractory B-ALL treated with immunotherapy, 11 (92%) achieved MRD-negative remission as assessed by flow cytometry; 10 patients (83%) underwent subsequent HSCT. Two patients with B-ALL in MRD-negative remission received blinatumomab due to severe infection and remained in remission after chemotherapy continuation. CONCLUSIONS: Blinatumomab and inotuzumab can induce deep remissions in patients with rrALL and facilitate subsequent HSCT or other cellular therapies. Blinatumomab can also serve as an effective bridging therapy during severe infection. The optimal timing, choice of immunotherapeutic agent(s), and duration of responses require further investigation via larger-scale clinical trials.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Recidiva Local de Neoplasia/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Adolescente , Adulto , Anticorpos Biespecíficos/administração & dosagem , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Inotuzumab Ozogamicina/administração & dosagem , Masculino , Recidiva Local de Neoplasia/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Prognóstico , Estudos Retrospectivos , Terapia de Salvação , Adulto JovemRESUMO
Allogeneic hematopoietic cell transplantation (HCT) for children with nonmalignant disorders is challenged by potential drug-related toxicities and poor engraftment. This retrospective analysis expands on our single pediatric medical center experience with targeted busulfan, fludarabine, and intravenous (IV) alemtuzumab as a low-toxicity regimen to achieve sustained donor engraftment. Sixty-two patients received this regimen for their first HCT for a nonmalignant disorder between 2004 and 2018. Donors were matched sibling in 27%, 8/8 HLA allele-matched unrelated in 50%, and 7/8 HLA allele-mismatched in 23% (some of whom received additional immunoablation with thiotepa or clofarabine). Five patients experienced graft failure for a cumulative incidence of 8.4% (95% CI, 1 to 16%). In engrafted patients, the median donor chimerism in whole blood and CD3, CD14/15, and CD19 subsets at 1-year were 96%, 90%, 99%, and 99%, respectively. Only one patient received donor lymphocyte infusions (DLIs) for poor chimerism. Two patients died following disease progression despite 100% donor chimerism. The 3-year cumulative incidence of treatment-related mortality was 10% (95% CI, 2 to 17%). Overall survival and event-free-survival at 3-years were 87% (95% CI, 78 to 95%) and 80% (95% CI, 70 to 90%), respectively. The 6-month cumulative incidence of grade II to IV acute graft-versus-host disease (GVHD) was 7% (95% CI, 3 to 13%), while the 3-year cumulative incidence of chronic GVHD was 5% (95% CI, 0 to 11%). These results suggest that use of targeted busulfan, fludarabine and IV alemtuzumab offers a well-tolerated option for children with nonmalignant disorders to achieve sustained engraftment with a low incidence of GVHD.
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Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Bussulfano/uso terapêutico , Criança , Doença Enxerto-Hospedeiro/etiologia , Humanos , Estudos Retrospectivos , Condicionamento Pré-Transplante , Vidarabina/uso terapêuticoRESUMO
AMP-activated protein kinase (AMPK) is a cellular energy sensor activated during energy stress to stimulate ATP production pathways and restore homeostasis. AMPK is widely expressed in the kidney and involved in mitochondrial protection and biogenesis upon acute renal ischemia, AMPK activity being blunted in metabolic disease-associated kidney disease. Since little is known about AMPK in the regulation of renal blood flow, the present study aimed to assess the role of AMPK in renal vascular function. Functional responses to the selective AMPK activator A769662 were assessed in intrarenal small arteries isolated from the kidney of renal tumour patients and Wistar rats and mounted in microvascular myographs to perform simultaneous measurements of intracellular calcium [Ca2+]i and tension. Superoxide (O2.-) and hydrogen peroxide (H2O2) production were measured by chemiluminescence and fluorescence and protein expression by Western blot. Activation of AMPK with A769662 increased AMPKα phosphorylation at Thr-172 and induced potent relaxations compared to AICAR in isolated human and rat intrarenal arteries, through both endothelium-dependent mechanisms involving nitric oxide (NO) and intermediate-conductance calcium-activated potassium (IKCa) channels, as well as activation of ATP-sensitive (KATP) channels and sarcoplasmic reticulum Ca2+-ATPase (SERCA) in vascular smooth muscle (VSM). Furthermore, AMPK activator reduced NADPH oxidase 4 (Nox4) and Nox2-derived reactive oxygen species (ROS) production. These results demonstrate that A769662 has potent vasodilator and antioxidant effects in intrarenal arteries. The benefits of AMPK activation in rat kidney are reproduced in human arteries and therefore vascular AMPK activation might be a therapeutic target in the treatment of metabolic disease-associated kidney injury.
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Proteínas Quinases Ativadas por AMP , Vasodilatação , Proteínas Quinases Ativadas por AMP/genética , Monofosfato de Adenosina , Adenilato Quinase , Animais , Humanos , Peróxido de Hidrogênio , Rim , Ratos , Ratos Wistar , Espécies Reativas de OxigênioRESUMO
Introducción: el análisis de la mortalidad hospitalaria permite evaluar la calidad de la asistencia médica. Las últimas publicaciones sobre mortalidad en el Hospital Infantil Dr. Robert Reid Cabral datan de 1997 Objetivo: conocer el comportamiento de la mortalidad en el Hospital Infantil Dr. Robert Reid Cabral durante el periodo 20132017 Métodos: estudio descriptivo. Se revisaron los libros de registro y actas de defunciones de los pacientes fallecidos en el Hospital Dr. Robert Reid Cabral durante el periodo 20132017. Resultados: 3,800 pacientes fallecieron, en promedio 760 fallecidos por año (margen 679-868). 79.9 % con menos de 5 años de edad; las muertes en menores de 1 año de edad representaron el 61.3 % y en el periodo neonatal el 26.1 %. La Sepsis/Shock Séptico (43.4 %) y la Hemorragia Pulmonar (15.4 %) fueron los dos principales diagnósticos de defunción; el 34 % de los fallecidos presentaban una morbilidad asociada al diagnóstico de defunción y en el 40 % la morbilidad asociada era una malformación congénita. El 69.5 % fallecieron en la Unidad de Cuidados Intensivos Pediátricos o Neonatal y 40 % de los pacientes fallecieron antes de las 48 horas de su ingreso al hospital. Conclusión: el grupo etario de mayor mortalidad son los menores de 1 año de edad, se evidencia un alto porcentaje de muertes con enfermedad crónica y malformaciones congénitas asociadas. El hecho de que el 40 % de los pacientes fallecieran antes de las 48 horas de su ingreso, indica la condición de gravedad en que estos pacientes llegan al hospital
Introduction: the analysis of hospital mortality allows to evaluate the quality of medical care. The latest publications on mortality at Dr. Robert Reid Cabral Children's Hospital date from 1997. Objective: to know the behavior of mortality in the Dr. Robert Reid Cabral Children's Hospital during the period 2013-2017. Methods: descriptive study. Registration books and death certificates of deceased patients at Dr. Robert Reid Cabral Hospital during 2013-2017 were reviewed. Results: 3,800 patients died, on average 760 deaths per year (margin 679-868). 79.9 % with less than 5 years of age; deaths in children under 1 year of age represented 61.3 % and in the neonatal period 26.1 %. Sepsis / Septic Shock (43.4 %) and Pulmonary Hemorrhage (15.4 %) were the two main diagnoses of death; 34 % of the deceased had a morbidity associated with the diagnosis of death and in 40 % the associated morbidity was a congenital malformation. 69.5 % died in the Pediatric or Neonatal Intensive Care Unit and 40 % of the patients died within 48 hours of admission to the hospital. Conclusion: the age group with the highest mortality are those under 1 year of age, a high percentage of deaths with chronic disease and associated congenital malformations are evident. The fact that 40 % of patients died before 48 hours of admission indicates the serious condition in which these patients arrive at the hospital.
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Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Mortalidade Infantil , Causas de Morte , Choque Séptico/mortalidade , Anormalidades Congênitas/mortalidade , Fatores de Risco , República Dominicana/epidemiologiaRESUMO
Introducción: el traumatismo cardíaco es una condición poco frecuente en edad pediátrica, ocurriendo en menos del 5 % de traumatismos torácicos. Afecta más frecuentemente los ventrículos que las aurículas. Según el mecanismo de injuria puede ser: cerrado (como las contusiones torácicas) o penetrante (como las heridas por arma blanca o armas de fuego). El siguiente documento tiene la intención de describir la presentación clínica y el manejo de un paciente pediátrico con traumatismo cardíaco penetrante; se pretendió realizar una revisión de literatura sobre otros casos de traumatismo cardíaco penetrante. Presentación del caso: se expone el caso clínico de un paciente masculino de 14 años de edad, quien es referido al centro por historia de herida de arma blanca en región precordial izquierda. Se recibe con inestabilidad hemodinámica y hemitórax izquierdo hipodinámico; luego de realizar estudios de imagen y laboratorio se decide realizar toracocentesis. Ante evidente deterioro clínico, se decide realizar exploración quirúrgica, donde se halla laceración del ventrículo izquierdo y hematoma pericárdico, y se procede a drenar hematoma y cardiorrafia de ventrículo izquierdo. Conclusión: luego de describir la presentación y manejo de nuestro paciente, llegamos a la conclusión de que la sospecha clínica y el diagnóstico y manejo precoz son imprescindibles para mejorar el pronóstico de estos traumatismos. Asimismo, entendemos pertinente la exploración quirúrgica temprana ante los casos de inestabilidad hemodinámica, evitando el retraso de un tratamiento oportuno
Introduction: Cardiac trauma is a rare condition in pediatrics, occurring in less than 5 % of thoracic trauma. It affects the ventricles more often than the atria. Depending on the mechanism of injury, it may be classified as closed (such as blunt chest traumas) or penetrating (such as wounds with a knife or guns). The following document has the intention to describe the clinical presentation and management of a pediatric patient with a penetrating cardiac trauma, and it was intended to conduct a literature review on other cases of penetrating cardiac trauma. Case presentation: We present the clinical case of a 14-year-old male, who is referred to the center with history of a knife wound in the left precordial region. He is received with hemodynamic instability and hypodynamic left hemithorax, and, after performing imaging and laboratory studies, it was decided to perform thoracentesis. In the presence of evident clinical deterioration, it was decided to perform surgical exploration, where laceration of the left ventricle and pericardial hematoma is evidenced, for which drainage of hematoma and left ventricle cardiorrhaphy were performed. Conclusion: After describing the presentation and management of our patient, we conclude that clinical suspicion and early diagnosis and management are essential to improve the prognosis of these injuries. Likewise, we recognize the pertinence of early surgical exploration in cases of hemodynamic instability, avoiding the delay of a timely treatment.
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Humanos , Masculino , Adolescente , Traumatismo por Reperfusão Miocárdica , Ferimentos e Lesões , Cardiologia , Saúde da CriançaRESUMO
PURPOSE AND METHODS: In human basal-like breast cancer, mutations and deletions in TP53 and BRCA1 are frequent oncogenic events. Thus, we interbred mice expressing the CRE-recombinase with mice harboring loxP sites at TP53 and BRCA1 (K14-Cre; p53f/f Brca1f/f) to test the hypothesis that tissue-specific deletion of TP53 and BRCA1 would give rise to tumors reflective of human basal-like breast cancer. RESULTS: In support of our hypothesis, these transgenic mice developed tumors that express basal-like cytokeratins and demonstrated intrinsic gene expression features similar to human basal-like tumors. Array comparative genomic hybridization revealed a striking conservation of copy number alterations between the K14-Cre; p53f/f Brca1f/f mouse model and human basal-like breast cancer. Conserved events included MYC amplification, KRAS amplification, and RB1 loss. Microarray analysis demonstrated that these DNA copy number events also led to corresponding changes in signatures of pathway activation including high proliferation due to RB1 loss. K14-Cre; p53f/f Brca1f/f also matched human basal-like breast cancer for a propensity to have immune cell infiltrates. Given the long latency of K14-Cre; p53f/f Brca1f/f tumors (~ 250 days), we created tumor syngeneic transplant lines, as well as in vitro cell lines, which were tested for sensitivity to carboplatin and paclitaxel. These therapies invoked acute regression, extended overall survival, and resulted in gene expression signatures of an anti-tumor immune response. CONCLUSION: These findings demonstrate that this model is a valuable preclinical resource for the study of human basal-like breast cancer.
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Modelos Animais de Doenças , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Animais , Proteína BRCA1 , Feminino , Humanos , Camundongos , Camundongos TransgênicosRESUMO
Compelling evidence has shown that, besides its putative effect on the regulation of the gonadal axis, estradiol (E2) exerts a dichotomic effect on the hypothalamus to regulate food intake and energy expenditure. The anorectic effect of E2 is mainly mediated by its action on the arcuate nucleus (ARC), whereas its effects on brown adipose tissue (BAT) thermogenesis occur in the ventromedial nucleus (VMH). Here, we demonstrate that central E2 decreases hypothalamic ceramide levels and endoplasmic reticulum (ER) stress. Pharmacological or genetic blockade of ceramide synthesis and amelioration of ER stress selectively occurring in the VMH recapitulate the effect of E2, leading to increased BAT thermogenesis, weight loss, and metabolic improvement. These findings demonstrate that E2 regulation of ceramide-induced hypothalamic lipotoxicity and ER stress is an important determinant of energy balance, suggesting that dysregulation of this mechanism may underlie some changes in energy homeostasis seen in females.
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Tecido Adiposo Marrom/fisiologia , Ceramidas/toxicidade , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Estradiol/farmacologia , Hipotálamo/fisiologia , Termogênese/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Animais , Estrogênios/farmacologia , Feminino , Homeostase , Hipotálamo/efeitos dos fármacos , RatosRESUMO
Recent data have demonstrated that the hypothalamic GRP78/BiP (glucose regulated protein 78 kDa/binding immunoglobulin protein) modulates brown adipose tissue (BAT) thermogenesis by acting downstream on AMP-activated protein kinase (AMPK). Herein, we aimed to investigate whether genetic over-expression of GRP78 in the ventromedial nucleus of the hypothalamus (VMH: a key site regulating thermogenesis) could ameliorate very high fat diet (vHFD)-induced obesity. Our data showed that stereotaxic treatment with adenoviruses harboring GRP78 in the VMH reduced hypothalamic endoplasmic reticulum ER stress and reversed vHFD-induced obesity. Herein, we also demonstrated that this body weight decrease was more likely associated with an increased BAT thermogenesis and browning of white adipose tissue (WAT) than to anorexia. Overall, these results indicate that the modulation of GRP78 in the VMH may be a target against obesity.
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Current evidence suggests that estradiol (E2), the main ovarian steroid, modulates energy balance by regulating both feeding and energy expenditure at the central level, through the energy sensor AMP-activated protein kinase (AMPK). We hypothesized that the hypothalamic mechanistic target of rapamycin (mTOR) pathway, a well-established nutrient sensor and modulator of appetite and puberty, could also mediate the anorectic effect of E2. Our data showed that ovariectomy (OVX) elicited a marked downregulation of the mTOR signaling in the arcuate nucleus of the hypothalamus (ARC), an effect that was reversed by either E2 replacement or central estrogen receptor alpha (ERα) agonism. The significance of this molecular signaling was given by the genetic inactivation of S6 kinase B1 (S6K1, a key downstream mTOR effector) in the ARC, which prevented the E2-induced hypophagia and weight loss. Overall, these data indicate that E2 induces hypophagia through modulation of mTOR pathway in the ARC.
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Anorexia/induzido quimicamente , Anorexia/metabolismo , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Estradiol/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Depressores do Apetite/farmacologia , Núcleo Arqueado do Hipotálamo/metabolismo , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Feminino , Ovariectomia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/fisiologiaRESUMO
Lipoprotein lipase (LPL) is expressed in different areas of the brain, including the hypothalamus and plays an important role in neural control of the energy balance, including feeding behavior and metabolic fluxes. This study tested the hypothesis that hypothalamic LPL participates in the control of body temperature. We first showed that cold exposure induces decreased activity and expression of LPL in the mouse hypothalamus. We then selectively deleted LPL in the mediobasal hypothalamus (MBH) through an adeno-associated virus approach in LPL-floxed mice and generated MBHΔ Lpl mice with 30-35% decrease in hypothalamic LPL activity. Results showed a decrease in body temperature in MBHΔ Lpl mice when compared with controls at 22°C. Exposure to cold (4°C for 4 h) decreased the body temperature of the control mice while that of the MBHΔ Lpl mice remained similar to that observed at 22°C. MBHΔ Lpl mice also showed increased energy expenditure during cold exposure, when compared to controls. Finally, the selective MBH deletion of LPL also increased the expression of the thermogenic PRMD16 and Dio2 in subcutaneous and perigonadal adipose tissues. Thus, the MBH LPL deletion seems to favor thermogenesis. These data demonstrate that for the first time hypothalamic LPL appears to function as a regulator of body temperature and cold-induced thermogenesis.
RESUMO
UNLABELLED: The opioid system is widely known to modulate the brain reward system and thus affect the behavior of humans and other animals, including feeding. We hypothesized that the hypothalamic opioid system might also control energy metabolism in peripheral tissues. Mice lacking the kappa opioid receptor (κOR) and adenoviral vectors overexpressing or silencing κOR were stereotaxically delivered in the lateral hypothalamic area (LHA) of rats. Vagal denervation was performed to assess its effect on liver metabolism. Endoplasmic reticulum (ER) stress was inhibited by pharmacological (tauroursodeoxycholic acid) and genetic (overexpression of the chaperone glucose-regulated protein 78 kDa) approaches. The peripheral effects on lipid metabolism were assessed by histological techniques and western blot. We show that in the LHA κOR directly controls hepatic lipid metabolism through the parasympathetic nervous system, independent of changes in food intake and body weight. κOR colocalizes with melanin concentrating hormone receptor 1 (MCH-R1) in the LHA, and genetic disruption of κOR reduced melanin concentrating hormone-induced liver steatosis. The functional relevance of these findings was given by the fact that silencing of κOR in the LHA attenuated both methionine choline-deficient, diet-induced and choline-deficient, high-fat diet-induced ER stress, inflammation, steatohepatitis, and fibrosis, whereas overexpression of κOR in this area promoted liver steatosis. Overexpression of glucose-regulated protein 78 kDa in the liver abolished hypothalamic κOR-induced steatosis by reducing hepatic ER stress. CONCLUSIONS: This study reveals a novel hypothalamic-parasympathetic circuit modulating hepatic function through inflammation and ER stress independent of changes in food intake or body weight; these findings might have implications for the clinical use of opioid receptor antagonists. (Hepatology 2016;64:1086-1104).
Assuntos
Dieta , Estresse do Retículo Endoplasmático , Hormônios Hipotalâmicos/fisiologia , Hipotálamo/fisiologia , Hepatopatias/etiologia , Melaninas/fisiologia , Hormônios Hipofisários/fisiologia , Receptores Opioides kappa/fisiologia , Animais , Inflamação/complicações , Inflamação/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-DawleyRESUMO
Aneurysmal disease is uncommon in children, and its presence often leads to suspicion of genetic disorders (Loeys-Dietz syndrome, Marfan syndrome, Ehlers-Danlos syndrome, tuberous sclerosis), trauma, and infection. We describe the case of a newborn boy with generalized left lower limb hypoplasia associated with diffuse areas of arteriectasis combined with areas of stenosis and fusiform aneurysms of the iliac, femoral, and popliteal arteries. No additional vascular territories were affected. The patient was asymptomatic, and no therapeutic intervention has been considered. Numerous complementary imaging and laboratory examinations failed to establish a definitive diagnosis. This collection of findings has not been previously reported.