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1.
Cell ; 179(6): 1276-1288.e14, 2019 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-31778654

RESUMEN

Although human genetic studies have implicated many susceptible genes associated with plasma lipid levels, their physiological and molecular functions are not fully characterized. Here we demonstrate that orphan G protein-coupled receptor 146 (GPR146) promotes activity of hepatic sterol regulatory element binding protein 2 (SREBP2) through activation of the extracellular signal-regulated kinase (ERK) signaling pathway, thereby regulating hepatic very low-density lipoprotein (VLDL) secretion, and subsequently circulating low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) levels. Remarkably, GPR146 deficiency reduces plasma cholesterol levels substantially in both wild-type and LDL receptor (LDLR)-deficient mice. Finally, aortic atherosclerotic lesions are reduced by 90% and 70%, respectively, in male and female LDLR-deficient mice upon GPR146 depletion. Taken together, these findings outline a regulatory role for the GPR146/ERK axis in systemic cholesterol metabolism and suggest that GPR146 inhibition could be an effective strategy to reduce plasma cholesterol levels and atherosclerosis.


Asunto(s)
Aterosclerosis/metabolismo , Hipercolesterolemia/metabolismo , Receptores Acoplados a Proteínas G/deficiencia , Animales , Aterosclerosis/sangre , Secuencia de Bases , Colesterol/sangre , Dependovirus/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ayuno , Femenino , Hepatocitos/metabolismo , Humanos , Hipercolesterolemia/sangre , Lipoproteínas VLDL/metabolismo , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , ARN Interferente Pequeño/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de LDL/metabolismo , Transducción de Señal , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Triglicéridos/sangre , Regulación hacia Arriba
2.
Proc Natl Acad Sci U S A ; 116(21): 10441-10446, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31040209

RESUMEN

Polymorphic HLAs form the primary immune barrier to cell therapy. In addition, innate immune surveillance impacts cell engraftment, yet a strategy to control both, adaptive and innate immunity, is lacking. Here we employed multiplex genome editing to specifically ablate the expression of the highly polymorphic HLA-A/-B/-C and HLA class II in human pluripotent stem cells. Furthermore, to prevent innate immune rejection and further suppress adaptive immune responses, we expressed the immunomodulatory factors PD-L1, HLA-G, and the macrophage "don't-eat me" signal CD47 from the AAVS1 safe harbor locus. Utilizing in vitro and in vivo immunoassays, we found that T cell responses were blunted. Moreover, NK cell killing and macrophage engulfment of our engineered cells were minimal. Our results describe an approach that effectively targets adaptive as well as innate immune responses and may therefore enable cell therapy on a broader scale.


Asunto(s)
Ingeniería Genética/métodos , Células Madre Pluripotentes/inmunología , Sistemas CRISPR-Cas , Línea Celular , Técnicas de Inactivación de Genes , Genes MHC Clase I , Genes MHC Clase II , Humanos
3.
Hepatology ; 59(6): 2196-206, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24442997

RESUMEN

UNLABELLED: The protein deacetylase, sirtuin 1 (SIRT1), involved in regulating hepatic insulin sensitivity, shows circadian oscillation and regulates the circadian clock. Recent studies show that circadian misalignment leads to insulin resistance (IR); however, the underlying mechanisms are largely unknown. Here, we show that CLOCK and brain and muscle ARNT-like protein 1 (BMAL1), two core circadian transcription factors, are correlated with hepatic insulin sensitivity. Knockdown of CLOCK or BMAL1 induces hepatic IR, whereas their ectopic expression attenuates hepatic IR. Moreover, circadian change of insulin sensitivity is impaired in Clock mutant, liver-specific Bmal1 knockout (KO) or Sirt1 KO mice, and CLOCK and BMAL1 are required for hepatic circadian expression of SIRT1. Further studies show that CLOCK/BMAL1 binds to the SIRT1 promoter to enhance its expression and regulates hepatic insulin sensitivity by SIRT1. In addition, constant darkness-induced circadian misalignment in mice decreases hepatic BMAL1 and SIRT1 levels and induces IR, which can be dramatically reversed by resveratrol. CONCLUSION: These findings offer new insights for coordination of the circadian clock and metabolism in hepatocytes by circadian regulation of hepatic insulin sensitivity via CLOCK/BMAL1-dependent SIRT1 expression and provide a potential application of resveratrol for combating circadian misalignment-induced metabolic disorders.


Asunto(s)
Factores de Transcripción ARNTL/fisiología , Proteínas CLOCK/fisiología , Ritmo Circadiano , Regulación hacia Abajo , Resistencia a la Insulina , Hígado/fisiología , Sirtuina 1/metabolismo , Animales , Antioxidantes/uso terapéutico , Oscuridad , Hepatocitos/fisiología , Ratones , Ratones Noqueados , Regiones Promotoras Genéticas , Resveratrol , Estilbenos/uso terapéutico
4.
Int J Mol Med ; 53(3)2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38299236

RESUMEN

Stroke, a debilitating cerebrovascular ailment, poses significant threats to human life and health. The intricate interplay between the gut­brain­microbiota axis (GBMA) and cerebral ischemia­reperfusion has increasingly become a focal point of scientific exploration, emerging as a pivotal research avenue in stroke pathophysiology. In the present review, the authors delved into the nexus between the GBMA and neuroinflammation observed post­stroke. The analysis underscored the pivotal roles of histone deacetylase 3 and neutrophil extracellular traps subsequent to stroke incidents. The influence of gut microbial compositions and their metabolites, notably short­chain fatty acids and trimethylamine N­oxide, on neuroinflammatory processes, was further elucidated. The involvement of immune cells, especially regulatory T­cells, and the intricate signaling cascades including cyclic GMP­AMP synthase/stimulator of interferon genes/Toll­like receptor, further emphasized the complex regulatory mechanisms of GBMA in cerebral ischemia/reperfusion injury (CI/RI). Collectively, the present review offered a comprehensive perspective on the metabolic, immune and inflammatory modulations orchestrated by GBMA, augmenting the understanding of its role in neuroinflammation following CI/RI.


Asunto(s)
Isquemia Encefálica , Daño por Reperfusión , Accidente Cerebrovascular , Humanos , Enfermedades Neuroinflamatorias , Eje Cerebro-Intestino , Isquemia Encefálica/metabolismo , Accidente Cerebrovascular/metabolismo , Daño por Reperfusión/metabolismo
5.
Tob Induc Dis ; 222024.
Artículo en Inglés | MEDLINE | ID: mdl-38550907

RESUMEN

INTRODUCTION: This study analyzes the impact of active smoking and secondhand smoke on the ischemic stroke burden of Pakistan, 1990-2019. METHODS: We used data from the Global Burden of Disease (GBD) database to conduct a comprehensive evaluation of ischemic stroke-related indicators in Pakistan, including the number of deaths, mortality rates, disability-adjusted life years (DALYs), DALY rates, and the estimated annual percentage change (EAPC). Joinpoint analysis was applied to assess sex-specific temporal trends in the burden of active smoking and secondhand smoke in Pakistan and regions of Pakistan. These assessments incorporated the Socio-Demographic Index (SDI) and we have made comparative analyses of epidemiological differences between active smoking and secondhand smoke exposure. RESULTS: The burden of ischemic stroke related to tobacco use is presented in terms of the age-standardized mortality rate (ASMR) and the age-standardized disability-adjusted life year rate (ASDR) per 100000 population. The results (ASMR/ASDR) for Pakistan were 6.04/130.81, in the middle SDI region 7.69/176.54, and low-middle SDI region 5.64/124.22. Pakistan's ASMR is higher than the global average of 5.85, while ASDR is lower than the global average of 140.23. From 1990 to 2019, a downward trend in both ASMR and ASDR was observed, indicating progress in controlling tobacco-related stroke burdens. Individuals aged ≥70 years experienced the highest rates of stroke (ASMR: 66.31; ASDR: 1091.20). Gender disparities were evident: men were more affected by active smoking (ASMR: 3.08; ASDR: 78.47) than women (ASMR: 0.79; ASDR: 20.76), while women faced a higher burden from secondhand smoke (ASMR: 0.66; ASDR: 16.33) compared to men (ASMR: 0.79; ASDR: 9.93). Regional differences within Pakistan show fluctuating death and DALY rates. Notably, an increasing trend in female ASDR due to secondhand smoke in the Khyber Pakhtunkhwa Region (annual percentage change, APC=0.17 from 2010 to 2019) calls for focused health interventions. CONCLUSIONS: The study finds ASMR for tobacco-related ischemic stroke in Pakistan exceeds global averages, with significant gender and age disparities in exposure to smoke, highlighting the need for targeted health interventions.

6.
Front Neurol ; 14: 1170780, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37483441

RESUMEN

Background: Epilepsy is one of the most common neurological diseases, affecting people of any age. Although the treatments of epilepsy are more and more diverse, the uncertainty regarding efficacy and adverse events still exists, especially in the control of childhood epilepsy. Methods: We performed a systematic review and meta- analysis following the Cochrane Handbook and preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Four databases including PubMed, Embase, Web of Science and Cochrane library were searched. Studies reporting the use of brivaracetam monotherapy or adjuvant therapy in children (aged ≤18 years) were eligible for inclusion. Each stage of the review was conducted by two authors independently. Random-effects models were used to combine effect sizes for the estimation of efficacy and safety. Results: A total of 1884 articles were retrieved, and finally 9 articles were included, enrolling 503 children with epilepsy. The retention rate of BRV treatment was 78% (95% CI: 0.64-0.91), the responder rate (reduction of seizure frequency ≥ 50%) was 35% (95% CI: 0.24-0.47), the freedom seizure rate (no seizure) was 18% (95% CI: 0.10-0.25), and the incidence rate of any treatment-emergent adverse events (TEAE) was 39% (95% CI: 0.09-0.68). The most common TEAE was somnolence, which had an incidence rate of 9% (95% CI: 0.07-0.12). And the incidence rate of mental or behavioral disorders was 12% (95% CI: 0.06-0.17). Conclusion: Our systematic review and meta-analysis showed that BRV seemed to be safe and effective in the treatment of childhood epilepsy.

7.
J Lipid Res ; 53(3): 358-367, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22231784

RESUMEN

Patt1 is a newly identified protein acetyltransferase that is highly expressed in liver. However, the role of Patt1 in liver is still unclear. We generated Patt1 liver-specific knockout (LKO) mice and mainly measured the effect of hepatic Patt1 deficiency on lipid metabolism. Hepatic Patt1 deficiency in male mice markedly decreases fat mass and dramatically alleviates age-associated accumulation of lipid droplets in liver. Moreover, hepatic Patt1 abrogation in male mice significantly reduces the liver triglyceride and free fatty acid levels, but it has no effect on liver cholesterol level, liver weight, and liver function. Consistently, primary cultured Patt1-deficient hepatocytes are resistant to palmitic acid-induced lipid accumulation, but hepatic Patt1 deficiency fails to protect male mice from high-fat diet-induced hepatic steatosis. Further studies show that hepatic Patt1 deficiency decreases fatty acid uptake, reduces lipid synthesis, and enhances fatty acid oxidation, which may contribute to the attenuated hepatic steatosis in Patt1 LKO mice. These results demonstrate that Patt1 plays an important role in hepatic lipid metabolism and have implications toward resolving age-associated hepatic steatosis.


Asunto(s)
Acetiltransferasas/metabolismo , Hígado Graso/prevención & control , Acetiltransferasas/genética , Animales , Peso Corporal/efectos de los fármacos , Células Cultivadas , Colesterol/metabolismo , Dieta Alta en Grasa/efectos adversos , Ingestión de Alimentos/efectos de los fármacos , Ácidos Grasos no Esterificados/metabolismo , Hígado Graso/inducido químicamente , Hígado Graso/genética , Hígado Graso/metabolismo , Immunoblotting , Inmunoprecipitación , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ácido Palmítico/efectos adversos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Triglicéridos/metabolismo
8.
Glia ; 58(2): 244-52, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19672968

RESUMEN

Astrocytes have important immune functions in CNS, and astrocytes stimulated by interferon-gamma were showed to have direct antimicrobial function. However whether astrocytes without the stimulation of cytokines have antibacterial function, and how this function is regulated are still largely unknown. In this study, we found that primary cultured astrocytes inhibited the growth of both gram-negative and gram-positive bacteria. Further more, we showed that interleukin-1beta (IL-1beta) enhanced the antibacterial effect in a dose-dependent manner, and the antibacterial effect of astrocytes from IL-1beta receptor-deficient mice failed to be enhanced by IL-1beta. IL-1beta stimulated IkappaBalpha degradation, NF-kappaB nuclear translocation, and transactivation in astrocytes. NF-kappaB inhibitors blocked NF-kappaB activation and the enhanced antibacterial effect induced by IL-1beta. In addition, overexpression of dominant negative IkappaBalpha in astrocytes inhibited IkappaBalpha degradation and NF-kappaB transactivation, and also inhibited the enhanced antibacterial effect induced by IL-1beta. All these data demonstrated that IL-1beta enhanced the antibacterial activity of astrocytes by activation of NF-kappaB.


Asunto(s)
Astrocitos/inmunología , Bacterias Gramnegativas/fisiología , Bacterias Grampositivas/fisiología , Interleucina-1beta/metabolismo , Viabilidad Microbiana , FN-kappa B/metabolismo , Transporte Activo de Núcleo Celular/fisiología , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Células Cultivadas , Proteínas I-kappa B/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , Receptores Tipo I de Interleucina-1/genética
9.
Nat Cell Biol ; 17(8): 994-1003, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26214132

RESUMEN

The use of human pluripotent stem cells for in vitro disease modelling and clinical applications requires protocols that convert these cells into relevant adult cell types. Here, we report the rapid and efficient differentiation of human pluripotent stem cells into vascular endothelial and smooth muscle cells. We found that GSK3 inhibition and BMP4 treatment rapidly committed pluripotent cells to a mesodermal fate and subsequent exposure to VEGF-A or PDGF-BB resulted in the differentiation of either endothelial or vascular smooth muscle cells, respectively. Both protocols produced mature cells with efficiencies exceeding 80% within six days. On purification to 99% via surface markers, endothelial cells maintained their identity, as assessed by marker gene expression, and showed relevant in vitro and in vivo functionality. Global transcriptional and metabolomic analyses confirmed that the cells closely resembled their in vivo counterparts. Our results suggest that these cells could be used to faithfully model human disease.


Asunto(s)
Diferenciación Celular , Linaje de la Célula , Células Endoteliales/fisiología , Células Madre Pluripotentes Inducidas/fisiología , Músculo Liso Vascular/fisiología , Miocitos del Músculo Liso/fisiología , Animales , Becaplermina , Biomarcadores/metabolismo , Proteína Morfogenética Ósea 4/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Linaje de la Célula/efectos de los fármacos , Técnicas de Cocultivo , Relación Dosis-Respuesta a Droga , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Células Endoteliales/trasplante , Perfilación de la Expresión Génica/métodos , Regulación del Desarrollo de la Expresión Génica , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/enzimología , Células Madre Pluripotentes Inducidas/trasplante , Metabolómica/métodos , Ratones Endogámicos NOD , Ratones SCID , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/enzimología , Músculo Liso Vascular/trasplante , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/enzimología , Miocitos del Músculo Liso/trasplante , Neovascularización Fisiológica , Fenotipo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-sis/farmacología , Factores de Tiempo , Transcripción Genética , Transfección , Factor A de Crecimiento Endotelial Vascular/farmacología , Vía de Señalización Wnt/efectos de los fármacos
10.
Artículo en Zh | MEDLINE | ID: mdl-12518234

RESUMEN

PHO85 is a versatile gene in Saccharomyces cerevisiae, which is involved in metabolism of inorganic phosphate and usage of carbon source, accumulation of glycogen, regulation of protein stability and cell cycle control. The viability of wild type budding yeast strain YPH499 and its derivative pho85Delta mutant, pho80 mutant, and pap1(pcl-7)Delta mutant in different cations were investigated and their tolerance to the cations(LC(50)) was measured. The results showed that the deletion of PHO85 or PHO80 gene both increased sensibility of Sacchromyces cerevisiae to ions K(+), Mg(2+), Zn(2+), Ca(2+) and Mn(2+), while the deletion of pap1(pcl-7) gene did not lead to such phenotype. The difference between the patterns of relative growth curve of the mutants and wild type strain in the above ions also implied that PHO80 was the unique PCLs in complex with PHO85 CDK, that were contributed to K(+) and Mg(2+) ion homeostasis control and there were some other PCLs besides PHO80 that were involved in Zn(2+), Ca(2+) and Mn(2+) tolerance regulation as cyclin of PHO85 CDK. Furthermore, the amount of the total cellular calcium of pho85Delta mutant, pho80Delta mutant and YPH499 indicated that the ability of calcium accumulation of pho85 mutant and pho80Delta mutant was impaired.


Asunto(s)
Cationes/farmacología , Quinasas Ciclina-Dependientes/fisiología , Ciclinas/fisiología , Proteínas Represoras/fisiología , Proteínas de Saccharomyces cerevisiae/fisiología , Saccharomyces cerevisiae/efectos de los fármacos , Calcio/metabolismo , Cloruro de Calcio/farmacología , División Celular/efectos de los fármacos , División Celular/genética , Cloruros/farmacología , Sulfato de Cobre/farmacología , Quinasas Ciclina-Dependientes/genética , Ciclinas/genética , Relación Dosis-Respuesta a Droga , Eliminación de Gen , Cloruro de Magnesio/farmacología , Compuestos de Manganeso/farmacología , Mutación , Proteínas Asociadas a Pancreatitis , Cloruro de Potasio/farmacología , Proteínas Represoras/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Proteínas de Saccharomyces cerevisiae/genética , Sulfato de Zinc/farmacología
11.
Cell Stem Cell ; 12(2): 238-51, 2013 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-23246482

RESUMEN

Transcription activator-like effector nucleases (TALENs) are a new class of engineered nucleases that are easier to design to cleave at desired sites in a genome than previous types of nucleases. We report here the use of TALENs to rapidly and efficiently generate mutant alleles of 15 genes in cultured somatic cells or human pluripotent stem cells, the latter for which we differentiated both the targeted lines and isogenic control lines into various metabolic cell types. We demonstrate cell-autonomous phenotypes directly linked to disease-dyslipidemia, insulin resistance, hypoglycemia, lipodystrophy, motor-neuron death, and hepatitis C infection. We found little evidence of TALEN off-target effects, but each clonal line nevertheless harbors a significant number of unique mutations. Given the speed and ease with which we were able to derive and characterize these cell lines, we anticipate TALEN-mediated genome editing of human cells becoming a mainstay for the investigation of human biology and disease.


Asunto(s)
Desoxirribonucleasas/genética , Células Madre/enzimología , Alelos , Genoma Humano/genética , Humanos , Mutación
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