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1.
Int J Cardiol ; 253: 7-13, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29306475

RESUMEN

AIMS: Lipoprotein-associated phospholipase A2 (Lp-PLA2), a novel biomarker for vascular inflammation, is associated with coronary endothelial dysfunction (CED) and independently predicts cardiovascular events. The current study aimed to determine whether darapladib, an orally administered Lp-PLA2 inhibitor, improved CED. METHODS AND RESULTS: Fifty-four patients with CED were enrolled in a double-blinded randomized placebo-controlled trial, and were randomized to receive oral darapladib, 160mg daily, or placebo. Coronary angiography and invasive coronary endothelial function assessment were performed at baseline and post-6months of treatment. Primary endpoints were change in coronary artery diameter and coronary blood flow in response to acetylcholine. Additionally, Lp-PLA2 activity was measured at baseline and on follow-up to evaluate for adherence and drug effect. Fifty-four patients were randomized to placebo (n=29) and darapladib (n=25). Mean age in darapladib group was 55.2.±11.7years vs. 54.0±10.5years (p=0.11). On follow-up, there was no significant difference in the percent response to acetylcholine of coronary artery diameter in treatment vs. placebo group (+3 (IQR -9, 15) vs. +3 (-12, 19); p=0.87) or coronary blood flow (-5 (IQR -24, 54) vs. 39 (IQR -26, 67); p=0.41). There was significant reduction in Lp-PLA2 activity in the treatment arm vs. placebo (-76 (IQR -113, -52) vs. -7(-21, -7); p<0.001). DISCUSSION: Lp-PLA2 inhibition with darapladib did not improve coronary endothelial function, despite significantly reduced Lp-PLA2 activity with darapladib. This study suggests endogenous Lp-PLA2 may not play a primary role in coronary endothelial function in humans. CLINICALTRIALS. GOV IDENTIFIER: NCT01067339.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/antagonistas & inhibidores , Benzaldehídos/administración & dosificación , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Vasos Coronarios/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Oximas/administración & dosificación , Inhibidores de Fosfolipasa A2/administración & dosificación , 1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Adulto , Anciano , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Velocidad del Flujo Sanguíneo/fisiología , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiología , Método Doble Ciego , Endotelio Vascular/diagnóstico por imagen , Endotelio Vascular/fisiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 42(2): 208-214, 2017 Feb 28.
Artículo en Chino | MEDLINE | ID: mdl-28255125

RESUMEN

OBJECTIVE: To analyze the relationship between lipoprotein-associated phospholipase A2 (Lp-PLA2) and ischemic stroke.
 Methods: Corresponding data, with case-control studies or cohorts regarding Lp-PLA2 and ischemic stroke, were retrieved from PubMed, Web of Science, Embase, the Cochrane Library, Chinese Biomedical Literature (CMB), VIP, China National Knowledge Infrastructure (CNKI), and Wanfang Database. Meta-analysis was performed by using Stata12.0.
 Results: Eight studies including 46 034 participants met the inclusion criteria. Meta-analysis showed that the combined effect of relative risk (RR) between Lp-PLA2 mass and ischemic stroke was [1.04 (0.98 to 1.11)] and that the combined effect of RR between Lp-PLA2 activity and ischemic stroke was [1.03 (0.96 to 1.10)], suggesting that Lp-PLA2 mass and activity were not associated with ischemic stroke.
 Conclusion: It cannot be considered that Lp-PLA2 mass and Lp-PLA2 activity was the risk factor for ischemic stroke.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Isquemia Encefálica/fisiopatología , Accidente Cerebrovascular/fisiopatología , Femenino , Humanos , Masculino , Factores de Riesgo
3.
J Immunol ; 197(6): 2090-101, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27534551

RESUMEN

Helper and cytotoxic T cells accomplish focused secretion through the movement of vesicles toward the microtubule organizing center (MTOC) and translocation of the MTOC to the target contact site. In this study, using Jurkat cells and OT-I TCR transgenic primary murine CTLs, we show that the dynein-binding proteins nuclear distribution E homolog 1 (NDE1) and dynactin (as represented by p150(Glued)) form mutually exclusive complexes with dynein, exhibit nonoverlapping distributions in target-stimulated cells, and mediate different transport events. When Jurkat cells expressing a dominant negative form of NDE1 (NDE1-enhanced GFP fusion) were activated by Staphylococcus enterotoxin E-coated Raji cells, NDE1 and dynein failed to accumulate at the immunological synapse (IS) and MTOC translocation was inhibited. Knockdown of NDE1 in Jurkat cells or primary mouse CTLs also inhibited MTOC translocation and CTL-mediated killing. In contrast to NDE1, knockdown of p150(Glued), which depleted the alternative dynein/dynactin complex, resulted in impaired accumulation of CTLA4 and granzyme B-containing intracellular vesicles at the IS, whereas MTOC translocation was not affected. Depletion of p150(Glued) in CTLs also inhibited CTL-mediated lysis. We conclude that the NDE1/Lissencephaly 1 and dynactin complexes separately mediate two key components of T cell-focused secretion, namely translocation of the MTOC and lytic granules to the IS, respectively.


Asunto(s)
Complejo Dinactina/fisiología , Dineínas/fisiología , Proteínas Asociadas a Microtúbulos/fisiología , Linfocitos T/fisiología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Señalización del Calcio , Citotoxicidad Inmunológica , Humanos , Células Jurkat , Centro Organizador de los Microtúbulos/metabolismo , Vesículas Secretoras/fisiología , Sinapsis/metabolismo , Linfocitos T Citotóxicos/inmunología
4.
Oncotarget ; 7(34): 55473-55490, 2016 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-27487154

RESUMEN

The non-keratinizing undifferentiated subtype of nasopharyngeal carcinoma (NPC) is a malignancy characterized by an intimate relationship between neoplastic cells and a non-neoplastic lymphoid component. Tumor-associated macrophages (TAMs) foster tumor progression through production of soluble mediators that support proliferation, angiogenesis, survival and invasion of malignant cells. However, the role of macrophages in the progression of NPC remains poorly understood. This study aims to investigate the functional and phenotypic changes that occur to macrophages in macrophage-NPC cell co-culture systems, and how these changes influence tumor cells. We found that monocytes, including THP-1 cells and primary human monocytes, co-cultured with C666-1 NPC cells upregulate expression of pro-inflammatory cytokines at the early stages, followed by the induction of metastasis-related genes and interferon-stimulated genes at the later stage of coculture, indicating that TAMs are "educated" by NPC cells for cancer progression. Importantly, the induction of these factors from the TAMs was also found to enhance the migratory capabilities of the NPC cells. We have also identified one of these macrophage-derived factor, phospholipase A2 Group 7 (PLA2G7), to be important in regulating tumor cell migration and a novel tumor-promoting factor in NPC. Further studies to characterize the role of PLA2G7 in tumor metastasis may help determine its potential as a therapeutic target in NPC.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Carcinoma/patología , Comunicación Celular , Macrófagos/fisiología , Monocitos/fisiología , Neoplasias Nasofaríngeas/patología , Línea Celular Tumoral , Movimiento Celular , Técnicas de Cocultivo , Citocinas/genética , Humanos , Carcinoma Nasofaríngeo , Invasividad Neoplásica , Metástasis de la Neoplasia
5.
Artículo en Japonés | MEDLINE | ID: mdl-27333658

RESUMEN

Cell positioning and neuronal network formation are crucial for proper brain function. Disrupted-In-Schizophrenia 1 (DISC1) is anterogradely transported to the neurite tips, together with Lis1, and functions in neurite extension via suppression of GSK3ß activity. Then, transported Lis1 is retrogradely transported and functions in cell migration. Here, we show that DISC1-binding zinc finger protein (DBZ) regulates mouse cortical cell positioning and neurite development in vivo, together with DISC1. DBZ hindered Ndel1 phosphorylation at threonine 219 and serine 251. DBZ depletion or expression of a double-phosphorylated mimetic form of Ndel1 impaired the transport of Lis1 and DISC1 to the neurite tips and hampered microtubule elongation. Moreover, application of DISC1 or a GSK3ß inhibitor rescued the impairments caused by DBZ insufficiency or double-phosphorylated Ndel1 expression. We concluded that DBZ controls cell positioning and neurite development by interfering with Ndel1 from disproportionate phosphorylation, which is critical for appropriate anterograde transport of the DISC1-complex.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , Proteínas Portadoras/metabolismo , Corteza Cerebral/citología , Corteza Cerebral/crecimiento & desarrollo , Proteínas de Unión al ADN/fisiología , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neuritas/fisiología , Neuronas/patología , Factores de Transcripción/fisiología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Animales , Transporte Biológico/genética , Corteza Cerebral/patología , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/fisiología , Glucógeno Sintasa Quinasa 3 beta , Humanos , Ratones , Proteínas Asociadas a Microtúbulos/fisiología , Proteínas del Tejido Nervioso/fisiología , Neuritas/patología , Fosforilación/genética , Esquizofrenia/genética , Esquizofrenia/patología
6.
Am J Physiol Lung Cell Mol Physiol ; 311(2): L303-16, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27233995

RESUMEN

We (66) have previously described an NSAID-insensitive intramitochondrial biosynthetic pathway involving oxidation of the polyunsaturated mitochondrial phospholipid, cardiolipin (CL), followed by hydrolysis [by calcium-independent mitochondrial calcium-independent phospholipase A2-γ (iPLA2γ)] of oxidized CL (CLox), leading to the formation of lysoCL and oxygenated octadecadienoic metabolites. We now describe a model system utilizing oxidative lipidomics/mass spectrometry and bioassays on cultured bovine pulmonary artery endothelial cells (BPAECs) to assess the impact of CLox that we show, in vivo, can be released to the extracellular space and may be hydrolyzed by lipoprotein-associated PLA2 (Lp-PLA2). Chemically oxidized liposomes containing bovine heart CL produced multiple oxygenated species. Addition of Lp-PLA2 hydrolyzed CLox and produced (oxygenated) monolysoCL and dilysoCL and oxidized octadecadienoic metabolites including 9- and 13-hydroxyoctadecadienoic (HODE) acids. CLox caused BPAEC necrosis that was exacerbated by Lp-PLA2 Lower doses of nonlethal CLox increased permeability of BPAEC monolayers. This effect was exacerbated by Lp-PLA2 and partially mimicked by authentic monolysoCL or 9- or 13-HODE. Control mice plasma contained virtually no detectable CLox; in contrast, 4 h after Pseudomonas aeruginosa (P. aeruginosa) infection, 34 ± 8 mol% (n = 6; P < 0.02) of circulating CL was oxidized. In addition, molar percentage of monolysoCL increased twofold after P. aeruginosa in a subgroup analyzed for these changes. Collectively, these studies suggest an important role for 1) oxidation of CL in proinflammatory environments and 2) possible hydrolysis of CLox in extracellular spaces producing lysoCL and oxidized octadecadienoic acid metabolites that may lead to impairment of pulmonary endothelial barrier function and necrosis.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Cardiolipinas/biosíntesis , Células Endoteliales/fisiología , Animales , Cardiolipinas/sangre , Bovinos , Células Cultivadas , Impedancia Eléctrica , Hidrólisis , Ratones Endogámicos C57BL , Oxidación-Reducción , Infecciones por Pseudomonas/sangre , Transducción de Señal
7.
Acta Physiol (Oxf) ; 218(1): 13-27, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27124368

RESUMEN

AIM: Platelet-activating factor acetyl hydrolase 1B1 (PAFAH1B1, also known as Lis1) is a protein essentially involved in neurogenesis and mostly studied in the nervous system. As we observed a significant expression of PAFAH1B1 in the vascular system, we hypothesized that PAFAH1B1 is important during angiogenesis of endothelial cells as well as in human vascular diseases. METHOD: The functional relevance of the protein in endothelial cell angiogenic function, its downstream targets and the influence of NONHSAT073641, a long non-coding RNA (lncRNA) with 92% similarity to PAFAH1B1, were studied by knockdown and overexpression in human umbilical vein endothelial cells (HUVEC). RESULTS: Knockdown of PAFAH1B1 led to impaired tube formation of HUVEC and decreased sprouting in the spheroid assay. Accordingly, the overexpression of PAFAH1B1 increased tube number, sprout length and sprout number. LncRNA NONHSAT073641 behaved similarly. Microarray analysis after PAFAH1B1 knockdown and its overexpression indicated that the protein maintains Matrix Gla Protein (MGP) expression. Chromatin immunoprecipitation experiments revealed that PAFAH1B1 is required for active histone marks and proper binding of RNA Polymerase II to the transcriptional start site of MGP. MGP itself was required for endothelial angiogenic capacity and knockdown of both, PAFAH1B1 and MGP, reduced migration. In vascular samples of patients with chronic thromboembolic pulmonary hypertension (CTEPH), PAFAH1B1 and MGP were upregulated. The function of PAFAH1B1 required the presence of the intact protein as overexpression of NONHSAT073641, which was highly upregulated during CTEPH, did not affect PAFAH1B1 target genes. CONCLUSION: PAFAH1B1 and NONHSAT073641 are important for endothelial angiogenic function.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Proteínas Asociadas a Microtúbulos/fisiología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , Proteínas de Unión al Calcio/biosíntesis , Proteínas de Unión al Calcio/genética , Células Cultivadas , Proteínas de la Matriz Extracelular/biosíntesis , Proteínas de la Matriz Extracelular/genética , Femenino , Técnicas de Silenciamiento del Gen , Histonas/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Neovascularización Fisiológica/genética , Neovascularización Fisiológica/fisiología , ARN Polimerasa II/metabolismo , ARN Largo no Codificante/fisiología , Tromboembolia/complicaciones , Tromboembolia/metabolismo , Cicatrización de Heridas , Proteína Gla de la Matriz
8.
Am J Respir Crit Care Med ; 191(1): 45-53, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25408961

RESUMEN

RATIONALE: Host antioxidant defense, consisting of enzymatic antioxidant activity and nonenzymatic antioxidant micronutrients, is implicated in asthma pathogenesis. Studies of antioxidant defense and adult incident asthma have either used measures of antioxidants estimated from questionnaires or not considered enzymatic aspects of host defense. OBJECTIVES: We conducted the first study designed and powered to investigate the association of antioxidant defenses on adult incident asthma. METHODS: In a nested case-control study, we followed Shanghai women (aged 40-70 years) without prevalent asthma at baseline, over 8 years. Subjects with incident asthma were ascertained prospectively by gold standard testing of symptomatic women and matched to two asymptomatic control subjects. MEASUREMENTS AND MAIN RESULTS: Baseline urinary F2-isoprostanes, plasma concentrations of antioxidant micronutrients (tocopherols, xanthines, carotenes, and lycopene), and antioxidant enzyme activity (platelet-activating factor acetylhydrolase [PAF-AH] and superoxide dismutase) were measured from samples collected before disease onset. Among 65,372 women, 150 (0.24%) developed asthma. F2-isoprostane levels before asthma onset were not different between cases and control subjects. Doubling of α-tocopherol concentrations and PAF-AH activity was associated with 50 and 37% decreased risk of incident asthma (α-tocopherol: adjusted odds ratio = 0.52; 95% confidence interval, 0.32-0.84; PAF-AH: adjusted odds ratio = 0.63; 95% confidence interval, 0.42-0.93). CONCLUSIONS: In this prospective study, α-tocopherol, within normal reference ranges, and PAF-AH enzymatic activity were associated with decreased asthma development. These modifiable risk factors may be an effective strategy to test for primary asthma prevention.


Asunto(s)
Antioxidantes/análisis , Asma/etiología , Estrés Oxidativo/inmunología , alfa-Tocoferol/inmunología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Adulto , Edad de Inicio , Anciano , Asma/enzimología , Asma/inmunología , Biomarcadores/sangre , Biomarcadores/orina , Estudios de Casos y Controles , China , F2-Isoprostanos/orina , Femenino , Humanos , Micronutrientes/sangre , Micronutrientes/inmunología , Persona de Mediana Edad , Factor de Activación Plaquetaria/fisiología , Estudios Prospectivos , Factores Protectores , Factores de Riesgo , alfa-Tocoferol/análisis
9.
G Ital Cardiol (Rome) ; 15(12): 664-9, 2014 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-25533115

RESUMEN

Phospholipase A(2) (PLA(2)) are enzymes that hydrolyze the ester bond of glycerophospholipids releasing free fatty acids and lysophospholipids, including the arachidonic acid, the precursor of the eicosanoids and the inflammatory cascades. PLA(2) are present in the atherosclerotic plaques and their direct involvement in the proatherogenic inflammatory response is well documented. Epidemiological and genetic studies have demonstrated the correlation of the PLA(2) mass and enzymatic activity with the incidence of cardiovascular diseases. The potential pro-atherogenic role of PLA(2) led to the development of two small molecules, varespladib, a reversible sPLA(2) inhibitor, and darapladib, a selective Lp-PLA(2) inhibitor. Both molecules have demonstrated antiatherosclerotic properties in animal models, and positive effects on atherosclerotic plaque composition evaluated in phase 2 clinical trials. On these grounds, the results of three phase 3 studies have recently been published: the VISTA-16 study with varespladib in patients with acute coronary syndrome, and the STABILITY and SOLID-TIMI 52 studies with darapladib in patients with stable coronary heart disease and acute coronary syndrome, respectively. Unexpectedly, both studies did not demonstrate an additional protective action of PLA 2 inhibitors over the standard of care treatment with statins, antiplatelet drugs, and coronary revascularization. In the present article, the enzymatic properties and the involvement of sPLA(2) and Lp-PLA(2) in atherogenesis are reviewed, with a focus on the results of experimental studies and clinical studies with both varespladib and darapladib inhibitors.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/antagonistas & inhibidores , 1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Aterosclerosis/etiología , Fosfolipasas A/antagonistas & inhibidores , Fosfolipasas A/fisiología , Acetatos/farmacología , Síndrome Coronario Agudo/tratamiento farmacológico , Aterosclerosis/enzimología , Benzaldehídos/farmacología , Ensayos Clínicos Fase III como Asunto , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Humanos , Indoles/farmacología , Cetoácidos , Lipoproteínas/fisiología , Oximas/farmacología , Inhibidores de Fosfolipasa A2/farmacología
11.
J Lipid Res ; 55(9): 1847-54, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24859738

RESUMEN

Mounting ambiguity persists around the functional role of the plasma form of platelet-activating factor acetylhydrolase (PAF-AH). Because PAF-AH hydrolyzes PAF and related oxidized phospholipids, it is widely accepted as an anti-inflammatory enzyme. On the other hand, its actions can also generate lysophosphatidylcholine (lysoPC), a component of bioactive atherogenic oxidized LDL, thus allowing the enzyme to have proinflammatory capabilities. Presence of a canonical lysoPC receptor has been seriously questioned for a multitude of reasons. Animal models of inflammation show that elevating PAF-AH levels is beneficial and not deleterious and overexpression of PAF receptor (PAF-R) also augments inflammatory responses. Further, many Asian populations have a catalytically inert PAF-AH that appears to be a severity factor in a range of inflammatory disorders. Correlation found with elevated levels of PAF-AH and CVDs has led to the design of a specific PAF-AH inhibitor, darapladib. However, in a recently concluded phase III STABILITY clinical trial, use of darapladib did not yield promising results. Presence of structurally related multiple ligands for PAF-R with varied potency, existence of multi-molecular forms of PAF-AH, broad substrate specificity of the enzyme and continuous PAF production by the so called bi-cycle of PAF makes PAF more enigmatic. This review seeks to address the above concerns.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Animales , Aterosclerosis/enzimología , Aterosclerosis/inmunología , Humanos , Hidrólisis , Mediadores de Inflamación/fisiología , Factor de Activación Plaquetaria/fisiología , Factores de Riesgo
12.
Best Pract Res Clin Endocrinol Metab ; 28(3): 281-94, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24840259

RESUMEN

Considerable progress has been achieved in the treatment of dyslipidemias. However, half of cardiovascular events occur in individuals with average or low cholesterol levels and there is still a considerable residual risk with 70% of patients having an event despite statin treatment. In the era of personalized medicine there is increased interest in the incorporation of individual biomarkers in risk score algorithms in order to improve cardiovascular risk stratification followed by the prompt initiation of preventive measures. Since the 2001 third report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation and Treatment on High Blood Cholesterol in Adults (ATP III) several studies have evaluated the prognostic value of lipid related biomarkers such as non-HDL-cholesterol, apolipoprotein B, apolipoprotein B/apolipoprotein A1 ratio, lipoprotein(a), lipoprotein-associated phospholipase A2, and C-reactive protein. This article tries to summarize the most recent results in this area.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Proteína C-Reactiva/fisiología , Dislipidemias/terapia , Lípidos/fisiología , Enfermedades Vasculares/prevención & control , 1-Alquil-2-acetilglicerofosfocolina Esterasa/sangre , Adulto , Apolipoproteínas/sangre , Apolipoproteínas/fisiología , Biomarcadores/sangre , Dislipidemias/sangre , Dislipidemias/complicaciones , Humanos , Lípidos/sangre , Lipoproteínas LDL/sangre , Lipoproteínas LDL/fisiología , Tamaño de la Partícula , Enfermedades Vasculares/sangre , Enfermedades Vasculares/etiología
13.
Nat Genet ; 46(3): 217-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24569235

RESUMEN

Cell fate regulation is a central component of maintaining tissue homeostasis, yet the mechanisms instructing cell division diversity in tissue-specific stem cells have not been well understood. A new study uncovers a central role for microtubule motor-regulating protein Lis1 in hematopoietic stem cell fate determination and in leukemogenesis.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/fisiología , Leucemia Mieloide/patología , Leucemia Mieloide/fisiopatología , Proteínas Asociadas a Microtúbulos/fisiología , Animales , Femenino , Humanos , Masculino , Embarazo
14.
Nat Genet ; 46(3): 245-52, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24487275

RESUMEN

Cell fate can be controlled through asymmetric division and segregation of protein determinants, but the regulation of this process in the hematopoietic system is poorly understood. Here we show that the dynein-binding protein Lis1 is critically required for hematopoietic stem cell function and leukemogenesis. Conditional deletion of Lis1 (also known as Pafah1b1) in the hematopoietic system led to a severe bloodless phenotype, depletion of the stem cell pool and embryonic lethality. Further, real-time imaging revealed that loss of Lis1 caused defects in spindle positioning and inheritance of cell fate determinants, triggering accelerated differentiation. Finally, deletion of Lis1 blocked the propagation of myeloid leukemia and led to a marked improvement in survival, suggesting that Lis1 is also required for oncogenic growth. These data identify a key role for Lis1 in hematopoietic stem cells and mark its directed control of asymmetric division as a critical regulator of normal and malignant hematopoietic development.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/fisiología , Leucemia Mieloide/patología , Leucemia Mieloide/fisiopatología , Proteínas Asociadas a Microtúbulos/fisiología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/antagonistas & inhibidores , 1-Alquil-2-acetilglicerofosfocolina Esterasa/deficiencia , 1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , Animales , Carcinogénesis , División Celular , Línea Celular Tumoral , Femenino , Hematopoyesis , Humanos , Células K562 , Leucemia Mieloide/genética , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Proteínas Asociadas a Microtúbulos/antagonistas & inhibidores , Proteínas Asociadas a Microtúbulos/deficiencia , Proteínas Asociadas a Microtúbulos/genética , Fenotipo , Embarazo , Huso Acromático/patología
15.
Clin Exp Obstet Gynecol ; 41(6): 613-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25551949

RESUMEN

Premature ovarian failure (POF) appears to be a complex disease entity with several underlying etiopathogenic contributions including the possibility of multiple distinctly different autoimmune mechanisms, in which inflammatory autoimmunity targeted to ovarian-specific germline antigens (e.g., zona pellucida proteins or Mater) or differentiation/regulatory factors (e.g. inhibin-alpha) were regarded as one of the most crucial factors. Platelet-activating factor (PAF) and PAF class oxidized phospholipids stimulate the occurrence and development of inflammation and atherosclerosis. PAF acetylhydrolase (PAF-AH) can hydrolyze PAF and PAF class oxidized phospholipids and eventually prevent the body from the damage of these inflammatory mediators. These findings indicate a potential relationship between PAF-AH and POF thus have major implications for the future health of women who suffer with premature ovarian failure.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Insuficiencia Ovárica Primaria/etiología , Femenino , Humanos , Oxidación-Reducción , Fosfolípidos/metabolismo , Insuficiencia Ovárica Primaria/metabolismo
16.
Eur J Clin Invest ; 44(2): 136-45, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24328921

RESUMEN

OBJECTIVES: In this study, we sought to determine the metabolic markers associated with structural valve degeneration (SVD). BACKGROUND: Structural valve degeneration (SVD) is the major cause of bioprosthetic valve failure leading to bioprostheses (BPs) stenosis or regurgitation. We hypothesized that lipoprotein-associated phospholipase A2 (Lp-PLA2) is involved in the SVD of BPs. METHODS: We included 197 patients who underwent aortic valve replacement with a bioprosthetic valve and had echocardiographic follow-up to evaluate valve function. Moreover, explanted BPs (n = 39) were analysed by immunohistochemistry for the expression of Lp-PLA2. RESULTS: After a mean follow-up of 7·9 ±0·2 years, forty-one patients (21%) were identified as developing SVD. Patients with SVD had significantly higher plasma level of Lp-PLA2 mass (151·8 ± 9·2 ng/mL vs. 133·2 ± 3·4 ng/mL, P = 0·03) and activity (27·6 ± 0·9 nmol/min/mL vs. 25·0 ± 0·4 nmol/min/mL, P = 0·005). Multivariate analysis revealed that Lp-PLA2 activity (OR: 1·09, 95% CI: 1·01-1·18; P = 0·03) was the strongest independent predictor of SVD. Immunohistochemistry studies of explanted BP showed that 77% of explanted BPs had the expression of Lp-PLA2, which correlated with the density of macrophages (CD68), and ox-LDL levels in bioprosthetic tissues. CONCLUSIONS: Increased blood plasma activity of Lp-PLA2 is associated with higher prevalence of SVD. These findings open new avenues for the identification of patients at risk for SVD and for the development of pharmacotherapy aiming at the prevention of SVD.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Bioprótesis , Oclusión de Injerto Vascular/etiología , Prótesis Valvulares Cardíacas , Falla de Prótesis/etiología , Anciano , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/etiología , Estenosis de la Válvula Aórtica/cirugía , Estudios Transversales , Ecocardiografía Doppler , Femenino , Humanos , Masculino , Estudios Prospectivos
17.
Rev Med Chil ; 141(11): 1382-8, 2013 Nov.
Artículo en Español | MEDLINE | ID: mdl-24718463

RESUMEN

BACKGROUND: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an inflammatory biomarker involved in atherosclerosis and directly associated with cardiovascular events. AIM: To determine Lp-PLA2 levels in asymptomatic subjects with differing cardiovascular risk. MATERIAL AND METHODS: We studied 152 subjects aged 46 ± 11 years (69 women). We recorded traditional cardiovascular risk factors, creatinine, ultrasensitive C-reactive protein, fibrinogen, fasting lipids, blood sugar and activity levels of Lp-PLA2. Cardiovascular risk was classified according to the number of risk factors of each subject (0,1-2 or ≥ 3 risk factors). Besides, we calculated global Framingham risk score. RESULTS: The average Framingham score of participants was 6%. Twenty percent of participants had no risk factors, 46% had 1 or 2 and 34% had ≥ 3. Mean Lp-PLA2 levels were 185 ± 48 nmol/ml/min (201 ± 49 in men and 166 ± 38 in women). Lp-PLA2 correlated significantly (p < 0,05 for all) with non-HDL cholesterol, LDL, HDL, creatinine, waist circumference, body mass index and Framingham risk score. There was no correlation with blood sugar, C-reactive protein, fibrinogen or smoking status. Lp-PLA2 levels were significantly higher according to the number of risk factors: 0 factors: 163 ± 43, 1-2 factors: 185 ± 45 and ≥ 3 factors: 201 ± 47 nmol/ml/min, respectively. Linear regression analysis showed that the best predictor of Lp-PLA2 was non-HDL cholesterol (ß = 0,74; p < 0,0001). CONCLUSIONS: Lp-PLA2 activity increased along with the number of cardiovascular risk factors and was correlated mainly with non -HDL cholesterol.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/sangre , Enfermedades Cardiovasculares/sangre , 1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Adulto , Aterosclerosis/sangre , Aterosclerosis/diagnóstico , Biomarcadores/sangre , Presión Sanguínea/fisiología , Índice de Masa Corporal , Proteína C-Reactiva/análisis , Creatinina/sangre , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo
18.
Eur Heart J ; 33(23): 2899-909, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22802388

RESUMEN

Certain members of the phospholipase A(2) superfamily of enzymes have established causal involvement in atherosclerosis, thus at least two groups of this family of enzymes have been considered potential candidates for the prevention of cardiovascular events. Recently completed experimental animal studies, human biomarker data, vascular imaging studies, and genome-wide atherosclerosis studies provide the rationale for proceeding with clinical outcome trials directed at inhibition of secretory phospholipase A(2) and lipoprotein-associated phospholipase A(2). A clinical trial with the sPLA(2) inhibitor varespladib methyl was recently terminated, while clinical trials with the Lp-PLA(2) inhibitor darapladib are being conducted in coronary heart disease patients. This article reviews the available experimental animal and human trial evidence that serve as the basis for the development of these two classes of phospholipase A(2) inhibitors.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Aterosclerosis/enzimología , Fosfolipasas A2 Secretoras/fisiología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/antagonistas & inhibidores , 1-Alquil-2-acetilglicerofosfocolina Esterasa/química , Acetatos/farmacología , Acetatos/uso terapéutico , Animales , Aterosclerosis/tratamiento farmacológico , Benzaldehídos/farmacología , Benzaldehídos/uso terapéutico , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/enzimología , Ensayos Clínicos como Asunto , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Cobayas , Humanos , Indoles/farmacología , Indoles/uso terapéutico , Cetoácidos , Ratones , Mutación Missense/genética , Isquemia Miocárdica/enzimología , Miocitos Cardíacos/enzimología , Oximas/farmacología , Oximas/uso terapéutico , Fosfolipasas A2 Secretoras/antagonistas & inhibidores , Fosfolipasas A2 Secretoras/química , Polimorfismo Genético/genética , Factores de Riesgo
19.
Panminerva Med ; 54(2): 83-90, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22525563

RESUMEN

High-density lipoprotein (HDL) is protective against atherosclerosis development. Other than its central role in reverse cholesterol transport, HDL exhibits several other mechanisms by which it is protective. These include antioxidative, anti-inflammatory and antiapoptopic activities and the normalisation of vascular function. In light of the current view that oxidative modification of low-density lipoprotein (LDL) is essential for the initiation and progression of atherosclerosis, the antioxidative properties of HDL may be an important protective mechanism. HDL can retard the oxidation of LDL and limit its atherogenicity. Several proteins are present on HDL and the evidence that some of them metabolise lipid peroxidation products of phospholipids, cholesteryl esters and triglycerides associated with LDL and vascular cell membranes are discussed in this review.


Asunto(s)
Antioxidantes/farmacología , Lipoproteínas HDL/farmacología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Animales , Apolipoproteína A-I/fisiología , Arildialquilfosfatasa/fisiología , Aterosclerosis/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Oxidación-Reducción , Fosfatidilcolina-Esterol O-Aciltransferasa/fisiología
20.
Biomarkers ; 17(4): 289-302, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22401038

RESUMEN

OBJECTIVE: To conduct a comprehensive, systematic review of studies assessing the significance of lipoprotein-associated phospholipase A2 in cardiovascular diseases (CVDs). MATERIAL AND METHODS: A review of the literature was performed using the search term "Lipoprotein-associated phospholipase A2 (Lp-PLA2)" and each of the following terms: "cardiovascular risk," "cardiovascular death," "atherosclerotic disease," "coronary events," "transient ischemic attack (TIA)," "stroke," and "heart failure." The searches were performed on Medline, Google Scholar and ClinicalTrials.gov. RESULTS: The majority of published studies showed a significant association between Lp-PLA2 levels and cardiovascular events after multivariate adjustment. The association was consistent across a wide variety of subjects of both sexes and different ethnic backgrounds. CONCLUSIONS: The role of Lp-PLA2 as a significant biomarker of vascular inflammation was confirmed, and Lp-PLA2 seems to be closely correlated to cardiovascular events. It may be an important therapeutic target and may have an important role in prevention, risk stratification and personalised medicine.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/fisiología , Enfermedades Cardiovasculares/enzimología , 1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/terapia , Humanos , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/fisiología , Lipoproteínas/metabolismo , Lipoproteínas/fisiología , Terapia Molecular Dirigida , Estrés Oxidativo
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