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1.
Nat Immunol ; 21(11): 1430-1443, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32839607

RESUMEN

Macrophages demonstrate remarkable plasticity that is essential for host defense and tissue repair. The tissue niche imprints macrophage identity, phenotype and function. The role of vascular endothelial signals in tailoring the phenotype and function of tissue macrophages remains unknown. The lung is a highly vascularized organ and replete with a large population of resident macrophages. We found that, in response to inflammatory injury, lung endothelial cells release the Wnt signaling modulator Rspondin3, which activates ß-catenin signaling in lung interstitial macrophages and increases mitochondrial respiration by glutaminolysis. The generated tricarboxylic acid cycle intermediate α-ketoglutarate, in turn, serves as the cofactor for the epigenetic regulator TET2 to catalyze DNA hydroxymethylation. Notably, endothelial-specific deletion of Rspondin3 prevented the formation of anti-inflammatory interstitial macrophages in endotoxemic mice and induced unchecked severe inflammatory injury. Thus, the angiocrine-metabolic-epigenetic signaling axis specified by the endothelium is essential for reprogramming interstitial macrophages and dampening inflammatory injury.


Asunto(s)
Reprogramación Celular , Metabolismo Energético , Epigénesis Genética , Inflamación/etiología , Inflamación/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Trombospondinas/genética , Animales , Biomarcadores , Reprogramación Celular/genética , Reprogramación Celular/inmunología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Técnica del Anticuerpo Fluorescente , Inflamación/patología , Ratones , Ratones Noqueados , Ratones Transgénicos , Trombospondinas/metabolismo
2.
Immunity ; 52(3): 475-486.e5, 2020 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-32164878

RESUMEN

Cytosolic DNA acts as a universal danger-associated molecular pattern (DAMP) signal; however, the mechanisms of self-DNA release into the cytosol and its role in inflammatory tissue injury are not well understood. We found that the internalized bacterial endotoxin lipopolysaccharide (LPS) activated the pore-forming protein Gasdermin D, which formed mitochondrial pores and induced mitochondrial DNA (mtDNA) release into the cytosol of endothelial cells. mtDNA was recognized by the DNA sensor cGAS and generated the second messenger cGAMP, which suppressed endothelial cell proliferation by downregulating YAP1 signaling. This indicated that the surviving endothelial cells in the penumbrium of the inflammatory injury were compromised in their regenerative capacity. In an experimental model of inflammatory lung injury, deletion of cGas in mice restored endothelial regeneration. The results suggest that targeting the endothelial Gasdermin D activated cGAS-YAP signaling pathway could serve as a potential strategy for restoring endothelial function after inflammatory injury.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas de Ciclo Celular/genética , Proliferación Celular/genética , ADN Mitocondrial/genética , Células Endoteliales/metabolismo , Inflamación/genética , Nucleotidiltransferasas/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Citosol/metabolismo , ADN Mitocondrial/metabolismo , Células Endoteliales/citología , Células HEK293 , Humanos , Inflamación/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Nucleótidos Cíclicos/metabolismo , Nucleotidiltransferasas/metabolismo , Proteínas de Unión a Fosfato/genética , Proteínas de Unión a Fosfato/metabolismo , Transducción de Señal , Proteínas Señalizadoras YAP
3.
Immunity ; 49(1): 56-65.e4, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-29958799

RESUMEN

Potassium (K+) efflux across the plasma membrane is thought to be an essential mechanism for ATP-induced NLRP3 inflammasome activation, yet the identity of the efflux channel has remained elusive. Here we identified the two-pore domain K+ channel (K2P) TWIK2 as the K+ efflux channel triggering NLRP3 inflammasome activation. Deletion of Kcnk6 (encoding TWIK2) prevented NLRP3 activation in macrophages and suppressed sepsis-induced lung inflammation. Adoptive transfer of Kcnk6-/- macrophages into mouse airways after macrophage depletion also prevented inflammatory lung injury. The K+ efflux channel TWIK2 in macrophages has a fundamental role in activating the NLRP3 inflammasome and consequently mediates inflammation, pointing to TWIK2 as a potential target for anti-inflammatory therapies.


Asunto(s)
Inflamasomas/metabolismo , Inflamación/fisiopatología , Macrófagos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Animales , Caspasa 1/deficiencia , Caspasa 1/metabolismo , Línea Celular , Inflamasomas/efectos de los fármacos , Interleucina-1beta/metabolismo , Lipopolisacáridos/farmacología , Lesión Pulmonar/metabolismo , Lesión Pulmonar/fisiopatología , Macrófagos/trasplante , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR/deficiencia , Canales de Potasio/efectos de los fármacos , Canales de Potasio/metabolismo , Canales de Potasio de Dominio Poro en Tándem/antagonistas & inhibidores , Canales de Potasio de Dominio Poro en Tándem/deficiencia , Quinina/farmacología , ARN Interferente Pequeño/farmacología , Receptores Purinérgicos P2X7/deficiencia , Receptores Purinérgicos P2X7/metabolismo , Sepsis/metabolismo , Sepsis/fisiopatología , Transducción de Señal/efectos de los fármacos
4.
BMC Cancer ; 24(1): 164, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38302968

RESUMEN

BACKGROUND: For high-risk stageIImismatch repair deficient (dMMR) colon cancers, the benefit of adjuvant chemotherapy remains debatable. The principal aim of this study was to evaluate the prognostic value of high-risk factors and the effect of oxaliplatin-based adjuvant chemotherapy among dMMR stageIIcolon cancers. METHODS: Patients with stage II dMMR colon cancers diagnosed between June 2011 and May 2018 were enrolled in the study. Clinicopathological characteristics, treatment, and follow-up data were retrospectively collected. The high-risk group was defined as having one of the following factors: pT4 disease, fewer than twelve lymph nodes harvested (< 12 LNs), poorly differentiated histology, perineural invasion (PNI), lymphatic vascular invasion (LVI), or elevated preoperative carcinoembryonic antigen (CEA). The low-risk group did not have any risk factors above. Factors associated with disease-free survival (DFS) were included in univariate and multivariate Cox analyses. RESULTS: We collected a total of 262 consecutive patients with stage II dMMR colon cancer. 179 patients (68.3%) have at least one high-risk factor. With a median follow-up of 50.1 months, the low-risk group was associated with a tended to have a better 3-year DFS than the high-risk group (96.4% vs 89.4%; P = 0.056). Both elevated preoperative CEA (HR 2.93; 95% CI 1.26-6.82; P = 0.013) and pT4 disease (HR 2.58; 95% CI 1.06-6.25; P = 0.037) were independent risk factors of recurrence. Then, the 3-year DFS was 92.6% for the surgery alone group and 88.1% for the adjuvant chemotherapy group (HR 1.64; 95% CI 0.67-4.02; P = 0.280). Furthermore, no survival benefit from oxaliplatin-based adjuvant chemotherapy was observed in the high-risk group and in the subgroups with pT4 disease or < 12 LNs. CONCLUSIONS: These data suggests that not all high-risk factors have a similar impact on stage II dMMR colon cancers. Elevated preoperative CEA and pT4 tumor stage are associated with increased recurrence risk. However, oxaliplatin-based adjuvant chemotherapy shows no survival benefits in stage II dMMR colon cancers, either with or without high-risk factors.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Colon , Neoplasias Colorrectales , Reparación de la Incompatibilidad de ADN , Síndromes Neoplásicos Hereditarios , Humanos , Estudios Retrospectivos , Oxaliplatino/uso terapéutico , Estadificación de Neoplasias , Antígeno Carcinoembrionario , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Neoplasias del Colon/cirugía , Pronóstico , Quimioterapia Adyuvante
5.
J Natl Compr Canc Netw ; 22(3)2024 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-38498975

RESUMEN

BACKGROUND: Neoadjuvant anti-PD-1 therapy has shown encouraging efficacy in patients with deficient DNA mismatch repair (dMMR)/microsatellite instability-high (MSI-H) locally advanced rectal cancer (LARC), which suggests its potential as a curative-intent therapy and a promising treatment option for organ preservation. We aimed to investigate the long-term outcomes of patients with dMMR/MSI-H LARC who experienced clinical complete response (cCR) after anti-PD-1 therapy. METHODS: We retrospectively analyzed patients with dMMR/MSI-H LARC who achieved cCR and received nonoperative management following neoadjuvant anti-PD-1-based treatment from 4 Chinese medical centers. Patients were followed up for at least 1 year after they achieved cCR, their clinical data were collected, and survival outcomes were analyzed using the Kaplan-Meier method. RESULTS: A total of 24 patients who achieved cCR and received nonoperative management from March 2018 to May 2022 were included, with a median age of 51.0 years (range, 19.0-77.0 years). The median treatment course to reach cCR was 6.0 (range, 1.0-12.0). Fifteen patients (62.5%) continued their treatments after experiencing cCR, and the median treatment course was 17.0 (range, 3.0-36.0). No local regrowth or distant metastasis was observed in a median follow-up time of 29.1 months (range, 12.6-48.5 months) after cCR. The 3-year disease-free and overall survivals were both 100%. CONCLUSIONS: Patients with dMMR/MSI-H locally advanced or low-lying rectal cancer who achieved cCR following anti-PD-1-based therapy had promising long-term outcomes. A prospective clinical trial with a larger sample size is required to further validate these findings.


Asunto(s)
Neoplasias Colorrectales , Neoplasias del Recto , Adulto , Anciano , Humanos , Persona de Mediana Edad , Adulto Joven , Neoplasias Colorrectales/genética , Reparación de la Incompatibilidad de ADN , Inmunoterapia , Inestabilidad de Microsatélites , Terapia Neoadyuvante , Neoplasias del Recto/genética , Neoplasias del Recto/terapia , Estudios Retrospectivos , Resultado del Tratamiento
6.
BMC Cancer ; 23(1): 3, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36593480

RESUMEN

BACKGROUND: Lymphovascular invasion (LVI) and perineural invasion (PNI) can indicate poor survival outcomes in colorectal cancer, but few studies have focused on stage III colon cancer. The current study aimed to confirm the prognostic value of LVI and PNI and identify patients who could benefit from a complete duration of adjuvant chemotherapy based on the two pathological factors. METHODS: We enrolled 402 consecutive patients with stage III colon cancer who received colon tumor resection from November 2007 to June 2016 at Sun Yat-sen University Cancer Center. Survival analyses were performed by using Kaplan-Meier method with log-rank tests. Risk factors related to disease-free survival (DFS) and overall survival (OS) were identified through Cox proportional hazards analysis. RESULTS: 141 (35.1%) patients presented with LVI, and 108 (26.9%) patients with PNI. The LVI-positive group was associated with poorer 3-year DFS (86.5% vs. 76.3%, P = 0.001) and OS (96.0% vs. 89.1%, P = 0.003) rates compared with the LVI-negative group. The PNI-positive group showed a worse outcome compared with the PNI-negative group in 3-year DFS rate (72.5% vs. 86.7%, P < 0.001). Moreover, LVI-positive group present better 3-year DFS and OS rate in patients completing 6-8 cycles of adjuvant chemotherapy than those less than 6 cycles (3-year DFS: 80.0% vs. 64.9%, P = 0.019; 3-year OS: 93.2% vs. 76.3%, P = 0.002). CONCLUSIONS: LVI is a superior prognostic factor to PNI in stage III colon cancer patients undergoing curative treatment. PNI status can noly predict the 3-year DFS wihout affecting the 3-year OS. Furthermore, LVI also represents an effective indicator for adjuvant chemotherapy duration.


Asunto(s)
Neoplasias del Colon , Humanos , Pronóstico , Estudios Retrospectivos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/cirugía , Supervivencia sin Enfermedad , Quimioterapia Adyuvante , Invasividad Neoplásica , Estadificación de Neoplasias
7.
Dis Colon Rectum ; 66(10): e996-e1005, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35485833

RESUMEN

BACKGROUND: Colorectal cancer with mismatch repair deficiency is usually less aggressive and associated with a lower risk of distant metastasis. Immune checkpoint inhibition, rather than traditional chemoradiotherapy, has shown great advantages in treating such patients. OBJECTIVE: This study aimed to verify the hypothesis that locally very advanced (T4b) colorectal cancer without distant metastases might present with higher probability of mismatch repair deficiency and be more sensitive to neoadjuvant immune checkpoint inhibition. DESIGN: This study was designed as a single-center retrospective observational study. SETTINGS: The study was conducted in a tertiary referral center in China. PATIENTS: The study included patients who were clinically diagnosed with T4bM0 colorectal cancer from 2008 to 2019. MAIN OUTCOME MEASURES: Clinicopathological characteristics, mismatch repair status, and survival outcomes of patients with mismatch repair deficiency were analyzed. RESULTS: A total of 268 patients were included. The incidence of patients with mismatch repair deficiency in the T4bM0 population was 27.6% (75/268), with 84.0% (63/75) in the colon and 16.0% (12/75) in the rectum. For tumors located in the proximal colon, 45.0% (50/111) exhibited mismatch repair deficiency, whereas the incidence of mismatch repair deficiency in sigmoid colon cancer and rectal cancer was only 15.9% (25/157). Neoadjuvant immune checkpoint inhibition significantly reduced the open surgery rate ( p = 0.000) and multivisceral resection rate ( p = 0.025). The pathological complete remission rate in the neoadjuvant immune checkpoint inhibition group was significantly higher than that in neoadjuvant chemoradiotherapy/chemotherapy group (70.0% vs 0%; p = 0.004). No tumor downstaging was observed after neoadjuvant chemotherapy. Neoadjuvant immune checkpoint inhibition provided significantly better disease-free survival ( p = 0.0078) and relatively longer overall survival ( p = 0.15) than other groups. LIMITATIONS: This study is limited by the possible selection bias and small sample size. CONCLUSIONS: Our data depicted the high incidence of mismatch repair deficiency in T4bM0 mismatch repair deficiency and the effectiveness of the neoadjuvant immune checkpoint inhibition group in organ preservation. Precision oncology requires identification of the protein status of mismatch repair at initial diagnosis to make a rational treatment decision for these patients. See Video Abstract at http://links.lww.com/DCR/B952 . LA INHIBICIN DEL PUNTO DE CONTROL INMUNITARIO NEOADYUVANTE MEJORA LA PRESERVACIN DE RGANOS EN EL CNCER COLORRECTAL TBM CON DEFICIENCIA DE REPARACIN DE ERRORES DE COINCIDENCIA UN ESTUDIO OBSERVACIONAL RETROSPECTIVO: ANTECEDENTES:Los pacientes con cáncer colorrectal con deficiencia en la reparación de desajustes suelen (dMMR) ser menos agresivos y se asocian con un menor riesgo de metástasis a distancia. La inhibición del punto de control inmunitario, en lugar de la quimiorradioterapia tradicional, ha mostrado grandes ventajas en el tratamiento de estos pacientes.OBJETIVO:Este estudio tuvo como objetivo verificar nuestra hipótesis de que el CCR localmente muy avanzado (T4b) sin metástasis a distancia podría presentarse con una mayor probabilidad de dMMR y ser más sensible a la inhibición del punto de control inmunitario neoadyuvante.DISEÑO:Este estudio fue diseñado como un estudio observacional retrospectivo de un solo centro.CONFIGURACIÓN:El estudio se realizó en un centro de referencia terciario en China.PACIENTES:Se incluyeron pacientes con diagnóstico clínico de CCR T4bM0 desde 2008 hasta 2019.PRINCIPALES MEDIDAS DE RESULTADO:Se analizaron las características clinicopatológicas, el estado de MMR y los resultados de supervivencia de los pacientes con dMMR.RESULTADOS:Se incluyeron un total de 268 pacientes. La incidencia de dMMR en la población T4bM0 fue del 27,6% (75/268), con un 84,0% (63/75) en colon y un 16,0% (12/75) en recto. Para los tumores ubicados en el colon proximal, el 45,0% (50/111) exhibió dMMR, mientras que la incidencia de dMMR en el cáncer de colon sigmoideo y el cáncer de recto fue solo del 15,9% (25/157). La inhibición del punto de control inmunitario neoadyuvante redujo significativamente la cirugía abierta y la tasa de resección multivisceral ( p = 0,000 y p = 0,025, respectivamente). La tasa de PCR en el grupo de inhibición del punto de control inmunitario neoadyuvante fue significativamente mayor que en el grupo de quimiorradioterapia/quimioterapia neoadyuvante (70,0% frente a 0%, p = 0,004). No se observó reducción del estadio del tumor después de la quimioterapia neoadyuvante. La inhibición del punto de control inmunitario neoadyuvante proporcionó una supervivencia sin enfermedad significativamente mejor ( p = 0,0078) y una supervivencia general relativamente más larga ( p = 0,15) que otros grupos.LIMITACIONES:Este estudio está limitado por el posible sesgo de selección y el pequeño tamaño de la muestra.CONCLUSIONES:Nuestros datos representan la alta incidencia de dMMR en T4bM0 CRC y la eficacia del grupo de inhibición del punto de control inmunitario neoadyuvante en la preservación de órganos. La oncología de precisión requiere la identificación del estado de la proteína MMR en el diagnóstico inicial para tomar una decisión de tratamiento racional para estos pacientes especiales. Consulte el Video Resumen en http://links.lww.com/DCR/B952 . (Traducción-Dr. Yesenia Rojas-Khalil ).


Asunto(s)
Neoplasias Colorrectales , Neoplasias del Recto , Humanos , Terapia Neoadyuvante , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Preservación de Órganos , Estadificación de Neoplasias , Medicina de Precisión , Neoplasias Colorrectales/patología , Estudios Retrospectivos , Neoplasias del Recto/cirugía , Reparación de la Incompatibilidad de ADN
8.
Circ Res ; 126(12): 1723-1745, 2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32216531

RESUMEN

RATIONALE: Right ventricular (RV) fibrosis in pulmonary arterial hypertension contributes to RV failure. While RV fibrosis reflects changes in the function of resident RV fibroblasts (RVfib), these cells are understudied. OBJECTIVE: Examine the role of mitochondrial metabolism of RVfib in RV fibrosis in human and experimental pulmonary arterial hypertension. METHODS AND RESULTS: Male Sprague-Dawley rats received monocrotaline (MCT; 60 mg/kg) or saline. Drinking water containing no supplement or the PDK (pyruvate dehydrogenase kinase) inhibitor dichloroacetate was started 7 days post-MCT. At week 4, treadmill testing, echocardiography, and right heart catheterization were performed. The effects of PDK activation on mitochondrial dynamics and metabolism, RVfib proliferation, and collagen production were studied in RVfib in cell culture. Epigenetic mechanisms for persistence of the profibrotic RVfib phenotype in culture were evaluated. PDK expression was also studied in the RVfib of patients with decompensated RV failure (n=11) versus control (n=7). MCT rats developed pulmonary arterial hypertension, RV fibrosis, and RV failure. MCT-RVfib (but not left ventricular fibroblasts) displayed excess mitochondrial fission and had increased expression of PDK isoforms 1 and 3 that persisted for >5 passages in culture. PDK-mediated decreases in pyruvate dehydrogenase activity and oxygen consumption rate were reversed by dichloroacetate (in RVfib and in vivo) or siRNA targeting PDK 1 and 3 (in RVfib). These interventions restored mitochondrial superoxide and hydrogen peroxide production and inactivated HIF (hypoxia-inducible factor)-1α, which was pathologically activated in normoxic MCT-RVfib. Redox-mediated HIF-1α inactivation also decreased the expression of TGF-ß1 (transforming growth factor-beta-1) and CTGF (connective tissue growth factor), reduced fibroblast proliferation, and decreased collagen production. HIF-1α activation in MCT-RVfib reflected increased DNMT (DNA methyltransferase) 1 expression, which was associated with a decrease in its regulatory microRNA, miR-148b-3p. In MCT rats, dichloroacetate, at therapeutic levels in the RV, reduced phospho-pyruvate dehydrogenase expression, RV fibrosis, and hypertrophy and improved RV function. In patients with pulmonary arterial hypertension and RV failure, RVfib had increased PDK1 expression. CONCLUSIONS: MCT-RVfib manifest a DNMT1-HIF-1α-PDK-mediated, chamber-specific, metabolic memory that promotes collagen production and RV fibrosis. This epigenetic mitochondrial-metabolic pathway is a potential antifibrotic therapeutic target.


Asunto(s)
Epigénesis Genética , Ventrículos Cardíacos/metabolismo , Hipertensión Pulmonar/metabolismo , Mitocondrias Cardíacas/metabolismo , Miofibroblastos/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Animales , Células Cultivadas , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Fibrosis , Ventrículos Cardíacos/patología , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Dinámicas Mitocondriales , Monocrotalina/toxicidad , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
9.
Proc Natl Acad Sci U S A ; 116(26): 12980-12985, 2019 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-31186359

RESUMEN

Increased pulmonary microvessel pressure experienced in left heart failure, head trauma, or high altitude can lead to endothelial barrier disruption referred to as capillary "stress failure" that causes leakage of protein-rich plasma and pulmonary edema. However, little is known about vascular endothelial sensing and transduction of mechanical stimuli inducing endothelial barrier disruption. Piezo1, a mechanosensing ion channel expressed in endothelial cells (ECs), is activated by elevated pressure and other mechanical stimuli. Here, we demonstrate the involvement of Piezo1 in sensing increased lung microvessel pressure and mediating endothelial barrier disruption. Studies were made in mice in which Piezo1 was deleted conditionally in ECs (Piezo1iΔEC ), and lung microvessel pressure was increased either by raising left atrial pressure or by aortic constriction. We observed that lung endothelial barrier leakiness and edema induced by raising pulmonary microvessel pressure were abrogated in Piezo1iΔEC mice. Piezo1 signaled lung vascular hyperpermeability by promoting the internalization and degradation of the endothelial adherens junction (AJ) protein VE-cadherin. Breakdown of AJs was the result of activation of the calcium-dependent protease calpain and degradation of the AJ proteins VE-cadherin, ß-catenin, and p120-catenin. Deletion of Piezo1 in ECs or inhibition of calpain similarly prevented reduction in the AJ proteins. Thus, Piezo1 activation in ECs induced by elevated lung microvessel pressure mediates capillary stress failure and edema formation secondary to calpain-induced disruption of VE-cadherin adhesion. Inhibiting Piezo1 signaling may be a useful strategy to limit lung capillary stress failure injury in response to elevated vascular pressures.


Asunto(s)
Endotelio Vascular/patología , Canales Iónicos/metabolismo , Microvasos/patología , Edema Pulmonar/patología , Insuficiencia Respiratoria/patología , Uniones Adherentes/patología , Uniones Adherentes/ultraestructura , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Presión Arterial/fisiología , Presión Sanguínea/fisiología , Cadherinas/genética , Cadherinas/metabolismo , Permeabilidad Capilar/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Células Endoteliales/citología , Células Endoteliales/patología , Células Endoteliales/ultraestructura , Endotelio Vascular/citología , Endotelio Vascular/ultraestructura , Femenino , Técnicas de Sustitución del Gen , Humanos , Presión Hidrostática/efectos adversos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Canales Iónicos/antagonistas & inhibidores , Canales Iónicos/genética , Pulmón/irrigación sanguínea , Masculino , Mecanotransducción Celular , Ratones , Ratones Noqueados , Microscopía Electrónica de Transmisión , Microvasos/citología , Microvasos/efectos de los fármacos , Cultivo Primario de Células , Edema Pulmonar/etiología , Edema Pulmonar/fisiopatología , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/prevención & control , Venenos de Araña/farmacología
10.
Int J Colorectal Dis ; 36(6): 1201-1208, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33511478

RESUMEN

PURPOSE: As a kind of secondary tumor of the ovary, ovarian metastasis from colorectal cancer (OMCRC) happens rarely. Prognostic factors of OMCRC are still undetermined. This study was conducted to analyze clinical characteristics and prognostic factors of OMCRC patients. METHODS: Data of patients with OMCRC were collected retrospectively from four large-capacity hospitals in China. Kaplan-Meier method was applied to estimate disease-specific overall survival (OS), and multivariate Cox regression analysis was used to identify prognostic factors. A novel nomogram was developed to estimate individual survival probability, whose performance was internally validated using concordance index (C-index) and calibration curve. RESULTS: Totally, 162 cases were eligible, with a median age at diagnosis of 49 years old. The median size of ovarian metastases was 9.0 cm (95% CI: 8.5-10.4 cm). 93.8% of patients received surgery of ovarian metastases. Median time from CRC diagnosis to metachronous ovarian metastasis was 13.0 months (95% CI: 13.5-17.7 months). Median OS after ovarian metastasis diagnosis was 26.0 months (95% CI: 22.3-29.7 months). Integrating univariate and multivariate analyses, eight factors (including age, menopausal status, primary tumor location, N stage of primary tumor, surgery of primary tumor, differentiation grade, bilateral metastasis, and systemic chemotherapy) were used to develop a novel nomogram, with a C-index of 0.65 (95% CI: 0.595-0.705). Calibration curves indicated relatively good agreement between predicted and actual survival. CONCLUSIONS: This nomogram could be a promising tool to help clinicians to estimate individual survival outcome of patients with OMCRC. Further study is warranted to validate the practicality of this model.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Ováricas , China/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
11.
Am J Respir Cell Mol Biol ; 63(4): 531-539, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32663411

RESUMEN

Caveolae are prominent plasmalemmal invaginations in endothelial cells, especially in the lung vasculature, which comprises a vast surface area. PV1 (plasmalemmal vesicle-associated protein-1), a 60-kD glycoprotein expressed in endothelial cells, is essential for generating spoke-like diaphragmatic structures that span the neck region of endothelial caveolae. However, their role in caveolae-mediated uptake and endothelial-barrier function is unknown. Here, we generated mice with endothelial cell-specific deletion of PV1 through tamoxifen-induced Cdh5.Cre.ERT2 (endothelial-specific vascular cadherin.Cre.estrogen receptor 2)-mediated excision of the floxed PV1 allele. We observed that loss of PV1 specifically in endothelial cells increased lung vascular permeability of fluid and protein, indicating that PV1 is required for maintenance of lung vascular-barrier integrity. Endothelial-specific PV1 deletion also increased caveolae-mediated uptake of tracer albumin compared with controls, promoted Au-albumin accumulation in the bulb of caveolae, and induced caveolar swelling. In addition, we observed the progressive loss of plasma proteins from the circulation and reduced arterial pressure resulting from transudation of water and protein as well as edema formation in multiple tissues, including lungs. These changes seen after endothelial-specific PV1 deletion occurred in the absence of disruption of endothelial junctions. We demonstrated that exposure of wild-type mice to endotoxin, which is known to cause acute lung injury and increase protein permeability, also significantly reduced PV1 protein expression. We conclude that the key function of PV1 is to regulate lung endothelial permeability through its ability to restrict the entry of plasma proteins such as albumin into caveolae and their transport through the endothelial barrier.


Asunto(s)
Permeabilidad Capilar/fisiología , Caveolas/metabolismo , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Pulmón/metabolismo , Proteínas de la Membrana/metabolismo , Albúminas/metabolismo , Animales , Endotelio Vascular/fisiología , Pulmón/fisiología , Ratones , Ratones Endogámicos C57BL
12.
Am J Respir Cell Mol Biol ; 62(2): 168-177, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31409093

RESUMEN

Disruption of alveolar-capillary barriers is a major complication of high-volume mechanical ventilation referred to as "ventilator-induced lung injury." The stretching force in alveoli is transmitted to endothelial cells, increasing the tension on underlying endothelial plasma membrane. The mechanosensor Piezo1, a plasma membrane cation channel, was inducibly deleted in endothelial cells of mice (Piezo1iEC-/-), which allowed us to study its role in regulating the endothelial barrier response to alveolar stretch. We observed significant increase in lung vascular permeability in Piezo1iEC-/- mice as compared with control Piezo1fl/fl mice in response to high-volume mechanical ventilation. We also observed that human lung endothelial monolayers depleted of Piezo1 and exposed to cyclic stretch had increased permeability. We identified the calcium-dependent cysteine protease calpain as a downstream target of Piezo1. Furthermore, we showed that calpain maintained stability of the endothelial barrier in response to mechanical stretch by cleaving Src kinase, which was responsible for disassembling endothelial adherens junctions. Pharmacological activation of calpain caused Src cleavage and thereby its inactivation, and it restored the disrupted lung endothelial barrier seen in Piezo1iEC-/- mice undergoing high-volume mechanical ventilation. Our data demonstrate that downregulation of Piezo1 signaling in endothelium is a critical factor in the pathogenesis of ventilator-induced lung injury, and thus augmenting Piezo1 expression or pharmacologically activating Piezo1 signaling may be an effective therapeutic strategy.


Asunto(s)
Uniones Adherentes/metabolismo , Células Endoteliales/metabolismo , Canales Iónicos/metabolismo , Pulmón/metabolismo , Animales , Permeabilidad Capilar/efectos de los fármacos , Membrana Celular/metabolismo , Endotelio Vascular/metabolismo , Ratones , Alveolos Pulmonares/metabolismo , Lesión Pulmonar Inducida por Ventilación Mecánica/metabolismo
13.
Am J Physiol Cell Physiol ; 318(5): C913-C930, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32159364

RESUMEN

Whole exome sequencing (WES) was used in the research of familial pulmonary arterial hypertension (FPAH). CAV1 and KCNK3 were found as two novel candidate genes of FPAH. However, few pathogenic genes were identified in idiopathic pulmonary arterial hypertension (IPAH). We conducted WES in 20 unrelated IPAH patients who did not carry the known PAH-pathogenic variants among BMPR2, CAV1, KCNK3, SMAD9, ALK1, and ENG. We found a total of 4,950 variants in 3,534 genes, including 4,444 single-nucleotide polymorphisms and 506 insertions/deletions (InDels). Through the comprehensive and multilevel analysis, we disclosed several novel signaling cascades significantly connected to IPAH, including variants related to cadherin signaling pathway, dilated cardiomyopathy, glucose metabolism, immune response, mucin-type O-glycosylation, phospholipase C (PLC)-activating G protein-coupled receptor (GPCR) signaling pathway, vascular contraction and generation, and voltage-dependent Ca2+ channels. We also conducted validation studies in five mutant genes related to PLC-activating GPCR signaling pathway potentially involved in intracellular calcium regulation through Sanger sequencing for mutation accuracy, qRT-PCR for mRNA stability, immunofluorescence for subcellular localization, Western blotting for protein level, Fura-2 imaging for intracellular calcium, and proliferation analysis for cell function. The validation experiments showed that those variants in CCR5 and C3AR1 significantly increased the rise of intracellular calcium and the variant in CCR5 profoundly enhanced proliferative capacity of human pulmonary artery smooth muscle cells. Thus, our study suggests that multiple genetically affected signaling pathways take effect together to cause the formation of IPAH and the development of right heart failure and may further provide new therapy targets or putative clues for the present treatments such as limited therapeutic effectiveness of Ca2+ channel blockers.


Asunto(s)
Hipertensión Pulmonar Primaria Familiar/genética , Insuficiencia Cardíaca/genética , Receptores CCR5/genética , Receptores de Complemento/genética , Adulto , Bloqueadores de los Canales de Calcio/efectos adversos , Bloqueadores de los Canales de Calcio/uso terapéutico , Señalización del Calcio/genética , Caveolina 1/genética , Proliferación Celular/efectos de los fármacos , Hipertensión Pulmonar Primaria Familiar/tratamiento farmacológico , Hipertensión Pulmonar Primaria Familiar/patología , Femenino , Células HEK293 , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/patología , Humanos , Masculino , Persona de Mediana Edad , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Proteínas del Tejido Nervioso/genética , Canales de Potasio de Dominio Poro en Tándem/genética , Arteria Pulmonar/metabolismo , Arteria Pulmonar/patología , Transducción de Señal/genética , Secuenciación del Exoma
14.
Am J Physiol Cell Physiol ; 316(1): C92-C103, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30427721

RESUMEN

Angiogenesis is initiated in response to a variety of external cues, including mechanical and biochemical stimuli; however, the underlying signaling mechanisms remain unclear. Here, we investigated the proangiogenic role of the endothelial mechanosensor Piezo1. Genetic deletion and pharmacological inhibition of Piezo1 reduced endothelial sprouting and lumen formation induced by wall shear stress and proangiogenic mediator sphingosine 1-phosphate, whereas Piezo1 activation by selective Piezo1 activator Yoda1 enhanced sprouting angiogenesis. Similarly to wall shear stress, sphingosine 1-phosphate functioned by activating the Ca2+ gating function of Piezo1, which in turn signaled the activation of the matrix metalloproteinase-2 and membrane type 1 matrix metalloproteinase during sprouting angiogenesis. Studies in mice in which Piezo1 was conditionally deleted in endothelial cells demonstrated the requisite role of sphingosine 1-phosphate-dependent activation of Piezo1 in mediating angiogenesis in vivo. These results taken together suggest that both mechanical and biochemical stimuli trigger Piezo1-mediated Ca2+ influx and thereby activate matrix metalloproteinase-2 and membrane type 1 matrix metalloproteinase and synergistically facilitate sprouting angiogenesis.


Asunto(s)
Canales Iónicos/deficiencia , Metaloproteinasa 14 de la Matriz/metabolismo , Neovascularización Fisiológica/fisiología , Transducción de Señal/fisiología , Animales , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Canales Iónicos/genética , Metaloproteinasa 14 de la Matriz/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos
15.
BMC Bioinformatics ; 19(1): 217, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29940845

RESUMEN

BACKGROUND: The heterogeneity of cells across tissue types represents a major challenge for studying biological mechanisms as well as for therapeutic targeting of distinct tissues. Computational prediction of tissue-specific gene regulatory networks may provide important insights into the mechanisms underlying the cellular heterogeneity of cells in distinct organs and tissues. RESULTS: Using three pathway analysis techniques, gene set enrichment analysis (GSEA), parametric analysis of gene set enrichment (PGSEA), alongside our novel model (HeteroPath), which assesses heterogeneously upregulated and downregulated genes within the context of pathways, we generated distinct tissue-specific gene regulatory networks. We analyzed gene expression data derived from freshly isolated heart, brain, and lung endothelial cells and populations of neurons in the hippocampus, cingulate cortex, and amygdala. In both datasets, we found that HeteroPath segregated the distinct cellular populations by identifying regulatory pathways that were not identified by GSEA or PGSEA. Using simulated datasets, HeteroPath demonstrated robustness that was comparable to what was seen using existing gene set enrichment methods. Furthermore, we generated tissue-specific gene regulatory networks involved in vascular heterogeneity and neuronal heterogeneity by performing motif enrichment of the heterogeneous genes identified by HeteroPath and linking the enriched motifs to regulatory transcription factors in the ENCODE database. CONCLUSIONS: HeteroPath assesses contextual bidirectional gene expression within pathways and thus allows for transcriptomic assessment of cellular heterogeneity. Unraveling tissue-specific heterogeneity of gene expression can lead to a better understanding of the molecular underpinnings of tissue-specific phenotypes.


Asunto(s)
Células/metabolismo , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Redes Reguladoras de Genes , Heterogeneidad Genética , Transcriptoma , Células/citología , Bases de Datos Factuales , Humanos , Especificidad de Órganos , Fenotipo , Factores de Transcripción/metabolismo
16.
Circulation ; 135(25): 2505-2523, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28381471

RESUMEN

BACKGROUND: The mechanisms underlying the dedifferentiation and lineage conversion of adult human fibroblasts into functional endothelial cells have not yet been fully defined. Furthermore, it is not known whether fibroblast dedifferentiation recapitulates the generation of multipotent progenitors during embryonic development, which give rise to endothelial and hematopoietic cell lineages. Here we established the role of the developmental transcription factor SOX17 in regulating the bilineage conversion of fibroblasts by the generation of intermediate progenitors. METHODS: CD34+ progenitors were generated after the dedifferentiation of human adult dermal fibroblasts by overexpression of pluripotency transcription factors. Sorted CD34+ cells were transdifferentiated into induced endothelial cells and induced erythroblasts using lineage-specific growth factors. The therapeutic potential of the generated cells was assessed in an experimental model of myocardial infarction. RESULTS: Induced endothelial cells expressed specific endothelial cell surface markers and also exhibited the capacity for cell proliferation and neovascularization. Induced erythroblasts expressed erythroid surface markers and formed erythroid colonies. Endothelial lineage conversion was dependent on the upregulation of the developmental transcription factor SOX17, whereas suppression of SOX17 instead directed the cells toward an erythroid fate. Implantation of these human bipotential CD34+ progenitors into nonobese diabetic/severe combined immunodeficiency (NOD-SCID) mice resulted in the formation of microvessels derived from human fibroblasts perfused with mouse and human erythrocytes. Endothelial cells generated from human fibroblasts also showed upregulation of telomerase. Cell implantation markedly improved vascularity and cardiac function after myocardial infarction without any evidence of teratoma formation. CONCLUSIONS: Dedifferentiation of fibroblasts to intermediate CD34+ progenitors gives rise to endothelial cells and erythroblasts in a SOX17-dependent manner. These findings identify the intermediate CD34+ progenitor state as a critical bifurcation point, which can be tuned to generate functional blood vessels or erythrocytes and salvage ischemic tissue.


Asunto(s)
Antígenos CD34/fisiología , Desdiferenciación Celular/fisiología , Células Endoteliales/fisiología , Eritroblastos/fisiología , Fibroblastos/fisiología , Factores de Transcripción SOXF/fisiología , Células Madre/fisiología , Animales , Células Cultivadas , Humanos , Recién Nacido , Ratones , Ratones Endogámicos NOD , Ratones SCID
17.
Am J Respir Crit Care Med ; 195(4): 515-529, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27648837

RESUMEN

RATIONALE: Pulmonary arterial hypertension (PAH) is an obstructive vasculopathy characterized by excessive pulmonary artery smooth muscle cell (PASMC) proliferation, migration, and apoptosis resistance. This cancer-like phenotype is promoted by increased cytosolic calcium ([Ca2+]cyto), aerobic glycolysis, and mitochondrial fission. OBJECTIVES: To determine how changes in mitochondrial calcium uniporter (MCU) complex (MCUC) function influence mitochondrial dynamics and contribute to PAH's cancer-like phenotype. METHODS: PASMCs were isolated from patients with PAH and healthy control subjects and assessed for expression of MCUC subunits. Manipulation of the pore-forming subunit, MCU, in PASMCs was achieved through small interfering RNA knockdown or MCU plasmid-mediated up-regulation, as well as through modulation of the upstream microRNAs (miRs) miR-138 and miR-25. In vivo, nebulized anti-miRs were administered to rats with monocrotaline-induced PAH. MEASUREMENTS AND MAIN RESULTS: Impaired MCUC function, resulting from down-regulation of MCU and up-regulation of an inhibitory subunit, mitochondrial calcium uptake protein 1, is central to PAH's pathogenesis. MCUC dysfunction decreases intramitochondrial calcium ([Ca2+]mito), inhibiting pyruvate dehydrogenase activity and glucose oxidation, while increasing [Ca2+]cyto, promoting proliferation, migration, and fission. In PAH PASMCs, increasing MCU decreases cell migration, proliferation, and apoptosis resistance by lowering [Ca2+]cyto, raising [Ca2+]mito, and inhibiting fission. In normal PASMCs, MCUC inhibition recapitulates the PAH phenotype. In PAH, elevated miRs (notably miR-138) down-regulate MCU directly and also by decreasing MCU's transcriptional regulator cAMP response element-binding protein 1. Nebulized anti-miRs against miR-25 and miR-138 restore MCU expression, reduce cell proliferation, and regress established PAH in the monocrotaline model. CONCLUSIONS: These results highlight miR-mediated MCUC dysfunction as a unifying mechanism in PAH that can be therapeutically targeted.


Asunto(s)
Canales de Calcio/genética , Proteínas de Unión al Calcio/genética , Proteínas de Transporte de Catión/genética , Terapia Genética/métodos , Hipertensión Pulmonar/genética , MicroARNs/genética , Proteínas de Transporte de Membrana Mitocondrial/genética , Músculo Liso Vascular/patología , Arteria Pulmonar/patología , Animales , Apoptosis/genética , Calcio/metabolismo , Canales de Calcio/metabolismo , Estudios de Casos y Controles , Técnicas de Cultivo de Célula/métodos , Proliferación Celular/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Citosol/metabolismo , Modelos Animales de Enfermedad , Regulación hacia Abajo/genética , Glucólisis , Humanos , Hipertensión Pulmonar/patología , Hipertensión Pulmonar/fisiopatología , Hipertensión Pulmonar/terapia , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/fisiopatología , Fenotipo , Arteria Pulmonar/efectos de los fármacos , Complejo Piruvato Deshidrogenasa/metabolismo , Ratas , Regulación hacia Arriba/genética
18.
Pflugers Arch ; 468(1): 43-58, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26395471

RESUMEN

The mammalian homeostatic oxygen sensing system (HOSS) initiates changes in vascular tone, respiration, and neurosecretion that optimize oxygen uptake and tissue oxygen delivery within seconds of detecting altered environmental or arterial PO2. The HOSS includes carotid body type 1 cells, adrenomedullary cells, neuroepithelial bodies, and smooth muscle cells (SMCs) in pulmonary arteries (PAs), ductus arteriosus (DA), and fetoplacental arteries. Hypoxic pulmonary vasoconstriction (HPV) optimizes ventilation-perfusion matching. In utero, HPV diverts placentally oxygenated blood from the non-ventilated lung through the DA. At birth, increased alveolar and arterial oxygen tension dilates the pulmonary vasculature and constricts the DA, respectively, thereby transitioning the newborn to an air-breathing organism. Though modulated by endothelial-derived relaxing and constricting factors, O2 sensing is intrinsic to PASMCs and DASMCs. Within the SMC's dynamic mitochondrial network, changes in PO2 alter the reduction-oxidation state of redox couples (NAD(+)/NADH, NADP(+)/NADPH) and the production of reactive oxygen species, ROS (e.g., H2O2), by complexes I and III of the electron transport chain (ETC). ROS and redox couples regulate ion channels, transporters, and enzymes, changing intracellular calcium [Ca(2+)]i and calcium sensitivity and eliciting homeostatic responses to hypoxia. In PASMCs, hypoxia inhibits ROS production and reduces redox couples, thereby inhibiting O2-sensitive voltage-gated potassium (Kv) channels, depolarizing the plasma membrane, activating voltage-gated calcium channels (CaL), increasing [Ca(2+)]i, and causing vasoconstriction. In DASMCs, elevated PO2 causes mitochondrial fission, increasing ETC complex I activity and ROS production. The DASMC's downstream response to elevated PO2 (Kv channel inhibition, CaL activation, increased [Ca(2+)]i, and rho kinase activation) is similar to the PASMC's hypoxic response. Impaired O2 sensing contributes to human diseases, including pulmonary arterial hypertension and patent DA.


Asunto(s)
Conducto Arterial/metabolismo , Pulmón/metabolismo , Mitocondrias Musculares/metabolismo , Músculo Liso Vascular/metabolismo , Oxígeno/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Canales de Calcio/metabolismo , Humanos , Pulmón/irrigación sanguínea , Oxígeno/sangre , Canales de Potasio/metabolismo
19.
FASEB J ; 28(1): 316-26, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24076965

RESUMEN

Mitochondrial fission, regulated by dynamin-related protein-1 (Drp1), is a newly recognized determinant of mitochondrial function, but its contribution to left ventricular (LV) impairment following ischemia-reperfusion (IR) injury is unknown. We report that Drp1 activation during IR results in LV dysfunction and that Drp1 inhibition is beneficial. In both isolated neonatal murine cardiomyocytes and adult rat hearts (Langendorff preparation) mitochondrial fragmentation and swelling occurred within 30 min of IR. Drp1-S637 (serine 637) dephosphorylation resulted in Drp1 mitochondrial translocation and increased mitochondrial fission. The Drp1 inhibitor Mdivi-1 preserved mitochondrial morphology, reduced cytosolic calcium, and prevented cell death. Drp1 siRNA similarly preserved mitochondrial morphology. In Langendorff hearts, Mdivi-1 reduced mitochondrial reactive oxygen species, improved LV developed pressure (92±5 vs. 28±10 mmHg, P<0.001), and lowered LV end diastolic pressure (10±1 vs. 86±13 mmHg, P<0.001) following IR. Mdivi-1 was protective if administered prior to or following ischemia. Because Drp1-S637 dephosphorylation is calcineurin sensitive, we assessed the effects of a calcineurin inhibitor, FK506. FK506 treatment prior to IR prevented Drp1-S637 dephosphorylation and preserved cardiac function. Likewise, therapeutic hypothermia (30°C) inhibited Drp1-S637 dephosphorylation and preserved mitochondrial morphology and myocardial function. Drp1 inhibition is a novel strategy to improve myocardial function following IR.


Asunto(s)
Dinaminas/metabolismo , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Animales , Inhibidores de la Calcineurina , Células Cultivadas , Dinaminas/genética , Immunoblotting , Inmunosupresores/farmacología , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Transmisión , Dinámicas Mitocondriales/efectos de los fármacos , Dinámicas Mitocondriales/genética , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Consumo de Oxígeno/genética , Quinazolinonas/farmacología , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tacrolimus/farmacología
20.
Circ Res ; 112(5): 802-15, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23334860

RESUMEN

RATIONALE: Closure of the ductus arteriosus (DA) is essential for the transition from fetal to neonatal patterns of circulation. Initial PO2-dependent vasoconstriction causes functional DA closure within minutes. Within days a fibrogenic, proliferative mechanism causes anatomic closure. Though modulated by endothelial-derived vasodilators and constrictors, O2 sensing is intrinsic to ductal smooth muscle cells and oxygen-induced DA constriction persists in the absence of endothelium, endothelin, and cyclooxygenase mediators. O2 increases mitochondrial-derived H2O2, which constricts ductal smooth muscle cells by raising intracellular calcium and activating rho kinase. However, the mechanism by which oxygen changes mitochondrial function is unknown. OBJECTIVE: The purpose of this study was to determine whether mitochondrial fission is crucial for O2-induced DA constriction and closure. METHODS AND RESULTS: Using DA harvested from 30 term infants during correction of congenital heart disease, as well as DA from term rabbits, we demonstrate that mitochondrial fission is crucial for O2-induced constriction and closure. O2 rapidly (<5 minutes) causes mitochondrial fission by a cyclin-dependent kinase- mediated phosphorylation of dynamin-related protein 1 (Drp1) at serine 616. Fission triggers a metabolic shift in the ductal smooth muscle cells that activates pyruvate dehydrogenase and increases mitochondrial H2O2 production. Subsequently, fission increases complex I activity. Mitochondrial-targeted catalase overexpression eliminates PO2-induced increases in mitochondrial-derived H2O2 and cytosolic calcium. The small molecule Drp1 inhibitor, Mdivi-1, and siDRP1 yield concordant results, inhibiting O2-induced constriction (without altering the response to phenylephrine or KCl) and preventing O2-induced increases in oxidative metabolism, cytosolic calcium, and ductal smooth muscle cells proliferation. Prolonged Drp1 inhibition reduces DA closure in a tissue culture model. CONCLUSIONS: Mitochondrial fission is an obligatory, early step in mammalian O2 sensing and offers a promising target for modulating DA patency.


Asunto(s)
Conducto Arterial/fisiología , GTP Fosfohidrolasas/fisiología , Proteínas Asociadas a Microtúbulos/fisiología , Dinámicas Mitocondriales/fisiología , Proteínas Mitocondriales/fisiología , Músculo Liso Vascular/fisiología , Oxígeno/fisiología , Vasoconstricción/fisiología , Animales , Animales Recién Nacidos , Calcio/metabolismo , Proliferación Celular , Células Cultivadas , Conducto Arterial/citología , Dinaminas , Femenino , Humanos , Peróxido de Hidrógeno/metabolismo , Recién Nacido , Masculino , Mitocondrias/metabolismo , Modelos Animales , Músculo Liso Vascular/citología , Consumo de Oxígeno/fisiología , Conejos , Técnicas de Cultivo de Tejidos , Quinasas Asociadas a rho/metabolismo
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