RESUMEN
CBL is rapidly phosphorylated upon insulin receptor activation. Mice whole body CBL depletion improved insulin sensitivity and glucose clearance; however, the precise mechanisms remain unknown. We depleted either CBL or its associated protein SORBS1/CAP independently in myocytes and assessed mitochondrial function and metabolism compared to control cells. CBL- and CAP-depleted cells showed increased mitochondrial mass with greater proton leak. Mitochondrial respiratory complex I activity and assembly into respirasomes were reduced. Proteome profiling revealed alterations in proteins involved in glycolysis and fatty acid degradation. Our findings demonstrate CBL/CAP pathway couples insulin signaling to efficient mitochondrial respiratory function and metabolism in muscle.
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Resistencia a la Insulina , Proteínas Proto-Oncogénicas c-cbl , Animales , Ratones , Metabolismo Energético , Insulina/metabolismo , Mitocondrias/metabolismo , Mitocondrias Musculares/metabolismo , Células Musculares/metabolismo , Proteínas Proto-Oncogénicas c-cbl/metabolismo , Respiración de la CélulaRESUMEN
Aging, obesity, and insulin resistance are associated with low levels of PGC1α and PGC1ß coactivators and defective mitochondrial function. We studied mice deficient for PGC1α and PGC1ß [double heterozygous (DH)] to investigate their combined pathogenic contribution. Contrary to our hypothesis, DH mice were leaner, had increased energy dissipation, a pro-thermogenic profile in BAT and WAT, and improved carbohydrate metabolism compared to wild types. WAT showed upregulation of mitochondriogenesis/oxphos machinery upon allelic compensation of PGC1α4 from the remaining allele. However, DH mice had decreased mitochondrial OXPHOS and biogenesis transcriptomes in mitochondria-rich organs. Despite being metabolically healthy, mitochondrial defects in DH mice impaired muscle fiber remodeling and caused qualitative changes in the hepatic lipidome. Our data evidence first the existence of organ-specific compensatory allostatic mechanisms are robust enough to drive an unexpected phenotype. Second, optimization of adipose tissue bioenergetics is sufficient to maintain a healthy metabolic phenotype despite a broad severe mitochondrial dysfunction in other relevant metabolic organs. Third, the decrease in PGC1s in adipose tissue of obese and diabetic patients is in contrast with the robustness of the compensatory upregulation in the adipose of the DH mice.
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Tejido Adiposo/metabolismo , Mitocondrias/genética , Proteínas Nucleares/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Factores de Transcripción/genética , Envejecimiento/genética , Animales , Modelos Animales de Enfermedad , Metabolismo Energético/genética , Heterocigoto , Resistencia a la Insulina/genética , Masculino , Ratones , Obesidad/genética , Termogénesis/genética , Transcriptoma/genéticaRESUMEN
The adipokine Neuregulin 4 (Nrg4) protects against obesity-induced insulin resistance. Here, we analyze how the downregulation of Nrg4 influences insulin action and the underlying mechanisms in adipocytes. Validated shRNA lentiviral vectors were used to generate scramble (Scr) and Nrg4 knockdown (KD) 3T3-L1 adipocytes. Adipogenesis was unaffected in Nrg4 KD adipocytes, but there was a complete impairment of the insulin-induced 2-deoxyglucose uptake, which was likely the result of reduced insulin receptor and Glut4 protein. Downregulation of Nrg4 enhanced the expression of proinflammatory cytokines. Anti-inflammatory agents recovered the insulin receptor, but not Glut4, content. Proteins enriched in Glut4 storage vesicles such as the insulin-responsive aminopeptidase (IRAP) and Syntaxin-6 as well as TBC1D4, a protein involved in the intracellular retention of Glut4 vesicles, also decreased by Nrg4 KD. Insulin failed to reduce autophagy in Nrg4 KD adipocytes, observed by a minor effect on mTOR phosphorylation, at the time that proteins involved in autophagy such as LC3-II, Rab11, and Clathrin were markedly upregulated. The lysosomal activity inhibitor bafilomycin A1 restored Glut4, IRAP, Syntaxin-6, and TBC1D4 content to those found in control adipocytes. Our study reveals that Nrg4 preserves the insulin responsiveness by preventing inflammation and, in turn, benefits the insulin regulation of autophagy.
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Autofagia/fisiología , Transportador de Glucosa de Tipo 4/metabolismo , Resistencia a la Insulina/fisiología , Neurregulinas/metabolismo , Receptor de Insulina/biosíntesis , Células 3T3 , Adipocitos/metabolismo , Animales , Línea Celular , Cistinil Aminopeptidasa/biosíntesis , Citocinas/biosíntesis , Desoxiglucosa/metabolismo , Regulación hacia Abajo , Proteínas Activadoras de GTPasa/biosíntesis , Inflamación/patología , Insulina/metabolismo , Ratones , Neurregulinas/biosíntesis , Neurregulinas/genética , Proteínas Qa-SNARE/biosíntesis , Interferencia de ARN , ARN Interferente Pequeño/genéticaRESUMEN
There is increasing interest in research into fruits as sources of secondary metabolites because of their potential bioactivities. In this study, the phenolic profiles of Malus domestica Anna and Jonagold cultivars from Costa Rica were determined by Ultra Performance Liquid Chromatography coupled with High Resolution Mass Spectrometry (HRMS) using a quadrupole-time-of-flight analyzer (UPLC-QTOF-ESI MS), on enriched-phenolic extracts from skins and flesh, obtained through Pressurized Liquid Extraction (PLE). In total, 48 different phenolic compounds were identified in the skin and flesh extracts, comprising 17 flavan-3-ols, 12 flavonoids, 4 chalcones, 1 glycosylated isoprenoid and 14 hydroxycinnamic acids and derivatives. Among extracts, the flesh of Jonagold exhibits a larger number of polyphenols and is especially rich in procyanidin trimers, tetramers and pentamers. Evaluating total phenolic content (TPC) and antioxidant activities using ORAC and DPPH procedures yields higher values for this extract (608.8 mg GAE/g extract; 14.80 mmol TE/g extract and IC50 = 3.96 µg/mL, respectively). In addition, cytotoxicity evaluated against SW620 colon cancer cell lines and AGS gastric cancer cell lines also delivered better effects for Jonagold flesh (IC50 = 62.4 and 60.0 µg/mL, respectively). In addition, a significant negative correlation (p < 0.05) was found between TPC and cytotoxicity values against SW620 and AGS adenocarcinoma (r = -0.908, and -0.902, respectively). Furthermore, a significant negative correlation (p < 0.05) was also found between the number of procyanidins and both antioxidant activities and cytotoxicity towards SW620 (r = -0.978) and AGS (r = -0.894) cell lines. These results align with Jonagold flesh exhibiting the highest abundance in procyanidin oligomers and yielding better cytotoxic and antioxidant results. In sum, our findings suggest the need for further studies on these Costa Rican apple extracts-and particularly on the extracts from Jonagold flesh-to increase the knowledge on their potential benefits for health.
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Antineoplásicos Fitogénicos/análisis , Antioxidantes/análisis , Malus/química , Polifenoles/análisis , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Costa Rica , Humanos , Espectrometría de Masas , Neoplasias/tratamiento farmacológico , Extractos Vegetales/análisis , Extractos Vegetales/farmacología , Polifenoles/farmacologíaRESUMEN
There is an increased interest in plum research because of their metabolites' potential bioactivities. In this study, the phenolic profiles of Prunus domestica commercial cultivars (Methley, Pisardii and Satsuma) in Costa Rica were determined by Ultra Performance Liquid Chromatography coupled with High Resolution Mass Spectrometry using a quadrupole-time-of-flight analyzer (UPLC-ESI-QTOF MS) on enriched phenolic extracts obtained through Pressurized Liquid Extraction (PLE) under acidic and neutral extraction conditions. In total, 41 different phenolic compounds were identified in the skin and flesh extracts, comprising 11 flavan-3-ols, 14 flavonoids and 16 hydroxycinnamic acids and derivatives. Neutral extractions for the skins and flesh from all of the cultivars yielded a larger number of compounds, and were particularly rich in the number of procyanidin trimers and tetramers when compared to the acid extractions. The total phenolic content (TPC) and antioxidant potential using the DPPH and ORAC methods exhibited better results for neutral extracts with Satsuma skins and Methley flesh, which showed the best values (685.0 and 801.6 mg GAE/g extract; IC50 = 4.85 and 4.39 µg/mL; and 12.55 and 12.22 mmol TE/g extract, respectively). A Two-Way ANOVA for cytotoxicity towards AGS gastric adenocarcinoma and SW620 colon adenocarcinoma indicated a significant difference (p < 0.05) for PLE conditions, with better results for neutral extractions, with Satsuma skin delivering the best results (IC50 = 60.7 and 46.7 µg/mL respectively) along with Methley flesh (IC50 = 76.3 and 60.9 µg/mL, respectively). In addition, a significant positive correlation was found between TPC and ORAC (r = 0.929, p < 0.05), as well as a significant negative correlation (p < 0.05) between TPC and cytotoxicity towards AGS and SW620 cell lines (r = -0.776, and -0.751, respectively). A particularly high, significant, negative correlation (p < 0.05) was found between the number of procyanidins and cytotoxicity against the AGS (r = -0.868) and SW620 (r = -0.855) cell lines. Finally, the PCA clearly corroborated that neutral extracts are a more homogenous group exhibiting higher antioxidant and cytotoxic results regardless of the part or cultivar; therefore, our findings suggest that PLE extracts under neutral conditions would be of interest for further studies on their potential health benefits.
Asunto(s)
Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Polifenoles/química , Polifenoles/farmacología , Prunus domestica/química , Línea Celular Tumoral , Supervivencia Celular , Cromatografía Líquida de Alta Presión , Costa Rica , Ácidos Cumáricos/análisis , Ácidos Cumáricos/química , Relación Dosis-Respuesta a Droga , Flavonoides/análisis , Humanos , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Glucose-dependent insulinotropic polypeptide (GIP) beyond its insulinotropic effects may regulate postprandial lipid metabolism. Whereas the insulinotropic action of GIP is known to be impaired in type 2 diabetes mellitus (T2DM), its adipogenic effect is unknown. We hypothesized that GIP is anabolic in human subcutaneous adipose tissue (SAT) promoting triacylglycerol (TAG) deposition through reesterification of nonesterified fatty acids (NEFA), and this effect may differ according to obesity status or glucose tolerance. Twenty-three subjects categorized into four groups, normoglycemic lean (n = 6), normoglycemic obese (n = 6), obese with impaired glucose regulation (IGR; n = 6), and obese T2DM (n = 5), participated in a double-blind, randomized, crossover study involving a hyperglycemic clamp with a 240-min GIP infusion (2 pmol·kg-1·min-1) or normal saline. Insulin, NEFA, SAT-TAG content, and gene expression of key lipogenic enzymes were determined before and immediately after GIP/saline infusions. GIP lowered NEFA concentrations in the obese T2DM group despite diminished insulinotropic activity (mean NEFA AUC0-4 h ± SE, 41,992 ± 9,843 µmol·l-1·min-1 vs. 71,468 ± 13,605 with placebo, P = 0.039, 95% CI: 0.31-0.95). Additionally, GIP increased SAT-TAG in obese T2DM (1.78 ± 0.4 vs 0.86 ± 0.1-fold with placebo, P = 0.043, 95% CI: 0.1-1.8). Such effect with GIP was not observed in other three groups despite greater insulinotropic activity. Reduction in NEFA concentration with GIP correlated with adipose tissue insulin resistance for all subjects (Pearson, r = 0.56, P = 0.005). There were no significant gene expression changes in key SAT lipid metabolism enzymes. In conclusion, GIP appears to promote fat accretion and thus may exacerbate obesity and insulin resistance in T2DM.
Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Polipéptido Inhibidor Gástrico/farmacología , Intolerancia a la Glucosa/metabolismo , Incretinas/farmacología , Lipogénesis/efectos de los fármacos , Obesidad/metabolismo , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adipogénesis/efectos de los fármacos , Adulto , Glucemia/metabolismo , Estudios de Casos y Controles , Estudios Cruzados , Diabetes Mellitus Tipo 2/complicaciones , Método Doble Ciego , Esterificación/efectos de los fármacos , Ácidos Grasos no Esterificados/metabolismo , Técnica de Clampeo de la Glucosa , Intolerancia a la Glucosa/complicaciones , Humanos , Insulina/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Grasa Subcutánea/citología , Triglicéridos/metabolismoRESUMEN
Respiratory syncytial virus (RSV) requires protein biosynthesis machinery to generate progeny. There is evidence that RSV might alter some translation components since stress granules are formed in their host cells. Consistent with these observations, we found that RSV induces dephosphorylation of 4EBP1 (eIF4E-binding protein), an important cellular translation factor. Our results show no correlation between the 4EBP1 dephosphorylation time and the decrease in the global rate of protein synthesis. Interestingly, treatment with rapamycin stimulates virus generation. The results suggest that RSV is a virus that still contains unknown mechanisms involved in the translation of their mRNAs through the alteration or modification of some translation factors, such as 4EBP1, possibly to favor its replicative cycle.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Fosfoproteínas/metabolismo , Biosíntesis de Proteínas , Virus Sincitial Respiratorio Humano/fisiología , Proteínas de Ciclo Celular , Línea Celular , Células Epiteliales/virología , Humanos , Fosforilación , ARN Mensajero/genética , Sirolimus/efectos adversos , Sirolimus/metabolismo , Sirolimus/farmacología , Replicación Viral/efectos de los fármacosRESUMEN
The insulin/IGF signaling pathway is a highly conserved regulator of metabolism in flies and mammals, regulating multiple physiological functions including lipid metabolism. Although insulin signaling is known to regulate the activity of a number of enzymes in metabolic pathways, a comprehensive understanding of how the insulin signaling pathway regulates metabolic pathways is still lacking. Accepted knowledge suggests the key regulated step in triglyceride (TAG) catabolism is the release of fatty acids from TAG via the action of lipases. We show here that an additional, important regulated step is the activation of fatty acids for beta-oxidation via Acyl Co-A synthetases (ACS). We identify pudgy as an ACS that is transcriptionally regulated by direct FOXO action in Drosophila. Increasing or reducing pudgy expression in vivo causes a decrease or increase in organismal TAG levels respectively, indicating that pudgy expression levels are important for proper lipid homeostasis. We show that multiple ACSs are also transcriptionally regulated by insulin signaling in mammalian cells. In sum, we identify fatty acid activation onto CoA as an important, regulated step in triglyceride catabolism, and we identify a mechanistic link through which insulin regulates lipid homeostasis.
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Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Ácidos Grasos/metabolismo , Insulina/metabolismo , Triglicéridos/metabolismo , Células 3T3 , Acilcoenzima A/metabolismo , Animales , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Regulación de la Expresión Génica , Células HEK293 , Humanos , Insulina/genética , Metabolismo de los Lípidos , Masculino , Metabolismo , Ratones , Transducción de Señal , Activación TranscripcionalRESUMEN
Type 2 Diabetes (T2D) is a highly prevalent chronic metabolic disease with strong co-morbidity with obesity and cardiovascular diseases. There is growing evidence supporting the notion that a crosstalk between mitochondria and the insulin signaling cascade could be involved in the etiology of T2D and insulin resistance. In this study we investigated the molecular basis of this crosstalk by using systems biology approaches. We combined, filtered, and interrogated different types of functional interaction data, such as direct protein-protein interactions, co-expression analyses, and metabolic and signaling dependencies. As a result, we constructed the mitochondria-insulin (MITIN) network, which highlights 286 genes as candidate functional linkers between these two systems. The results of internal gene expression analysis of three independent experimental models of mitochondria and insulin signaling perturbations further support the connecting roles of these genes. In addition, we further assessed whether these genes are involved in the etiology of T2D using the genome-wide association study meta-analysis from the DIAGRAM consortium, involving 8,130 T2D cases and 38,987 controls. We found modest enrichment of genes associated with T2D amongst our linker genes (pâ=â0.0549), including three already validated T2D SNPs and 15 additional SNPs, which, when combined, were collectively associated to increased fasting glucose levels according to MAGIC genome wide meta-analysis (pâ=â8.12×10(-5)). This study highlights the potential of combining systems biology, experimental, and genome-wide association data mining for identifying novel genes and related variants that increase vulnerability to complex diseases.
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Diabetes Mellitus Tipo 2 , Estudio de Asociación del Genoma Completo , Resistencia a la Insulina/genética , Mitocondrias , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Regulación de la Expresión Génica , Predisposición Genética a la Enfermedad , Glucosa/metabolismo , Humanos , Insulina/genética , Insulina/metabolismo , Redes y Vías Metabólicas , Mitocondrias/genética , Mitocondrias/metabolismo , Obesidad/genética , Polimorfismo de Nucleótido Simple , Biología de SistemasRESUMEN
Rotaviruses are the most important agent of severe gastroenteritis in young children. Early in infection, these viruses take over the host translation machinery, causing a severe shutoff of cell protein synthesis while viral proteins are efficiently synthesized. In infected cells, there is an accumulation of the cytoplasmic poly(A)-binding protein in the nucleus, induced by the viral protein NSP3. Here we found that poly(A)-containing mRNAs also accumulate and become hyperadenylated in the nuclei of infected cells. Using reporter genes bearing the untranslated regions (UTRs) of cellular or viral genes, we found that the viral UTRs do not determine the efficiency of translation of mRNAs in rotavirus-infected cells. Furthermore, we showed that while a polyadenylated reporter mRNA directly delivered into the cytoplasm of infected cells was efficiently translated, the same reporter introduced as a plasmid that needs to be transcribed and exported to the cytoplasm was poorly translated. Altogether, these results suggest that nuclear retention of poly(A)-containing mRNAs is one of the main strategies of rotavirus to control cell translation and therefore the host antiviral and stress responses.
Asunto(s)
Núcleo Celular/metabolismo , Regulación hacia Abajo , Interacciones Huésped-Patógeno , ARN Mensajero/metabolismo , Infecciones por Rotavirus/genética , Infecciones por Rotavirus/metabolismo , Rotavirus/metabolismo , Transporte Activo de Núcleo Celular , Núcleo Celular/genética , Regulación de la Expresión Génica , Humanos , Biosíntesis de Proteínas , ARN Mensajero/genética , Rotavirus/genética , Infecciones por Rotavirus/virologíaRESUMEN
OBJECTIVE: To investigate renal functional outcomes of surveillance, embolization, and surgery for angiomyolipomas (AML). METHODS: Longitudinal data regarding patients with AML were analyzed retrospectively in this 2-center study. Demographic, radiographic, and functional data were tabulated according to treatment type. Primary outcome was change in renal function from diagnosis to within 6 months postdiagnosis (interim) and to latest glomerular filtration rate (GFR) assessment. RESULTS: 318 patients were diagnosed with AMLs; mean follow-up was 6.2 years. 184 patients (57.9%) were managed with surveillance, 30 (9.4%) underwent embolization, and 103 (32.4%) underwent surgery (91 partial nephrectomy; 12 radical nephrectomy). Baseline characteristics, including tumor size, age, and race differed between the 3 groups (P<.05). Surveilled AMLs were smaller (P<.001) than the intervention groups: 1.9 cm vs 5.4 cm (embolization) and 4.9 cm (surgery). Greater interim decreases in GFR were observed following intervention with embolization (-14.0%) or surgery (-11.8%), when compared with surveillance (-4.1%); however, this was not statistically significant (P=.19). Latest GFR was also reduced more (P=.02) with embolization (-14.1%) and surgery (-14.7%) when compared to surveillance (-6.0%). At latest determination, chronic kidney disease progression by at least one stage occurred in 37.8% overall, including 33.7% of surveilled patients, and was not statistically different across the three cohorts (P=.074). CONCLUSION: Within the study limitations, surveillance appears to be appropriate for most AML patients; embolization and surgical intervention should be reserved for selected patients with large and/or symptomatic AML. Renal functional deterioration is common in patients with AML, whether managed with surveillance, embolization, or surgery. Long-term monitoring of renal function should be obligatory for all AML patients.
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Angiomiolipoma , Embolización Terapéutica , Neoplasias Renales , Humanos , Angiomiolipoma/cirugía , Neoplasias Renales/cirugía , Neoplasias Renales/patología , Estudios Retrospectivos , Riñón/fisiología , Riñón/patología , Nefrectomía , Resultado del TratamientoRESUMEN
OBJECTIVE: Metabolic dysfunction-associated fatty liver disease (MAFLD) is a poor attended disease, which has gained attention due the elevated number of cases in countries as Mexico, where the incidence is the number 4th globally. MAFLD develops in obese or overweighted individuals and is characterized by triglycerides accumulation in the liver, this condition can develop to hepatocellular carcinoma. It has been observed that MAFLD depends on the genetics and lifestyle. Due to the high prevalence of this disease among Hispanic population, we focused on this study in the characteristics and prevalence of MAFLD in Mexican patients. METHODS: In this study were included 572 overweighted and obese patients, who underwent a screening analysis using the fatty liver index (IHG), clinical parameters were analysed, demographic and comorbidities. Frequency of variables were obtained, and the data were analysed by Chi-square test or Fisher test, odd ratio (OR) and binary logistic regression. RESULTS: A MALFD prevalence of 37% were obtained, where the history of familiar obesity, paracetamol usage, carbohydrate and fat intake are shown to be risk factors. It was found that high blood pressure, central obesity and hypertriglyceridemia were also associated to the MAFLD development. On the other hand, physical exercise was a protector factor. CONCLUSIONS: Our results show the necessity to study the MAFLD causalities in Mexican patients, focused on the paracetamol intake.
OBJETIVO: La enfermedad hepática grasa asociada a disfunción metabólica (MAFLD) es una enfermedad poco considerada, que ha recibido atención debido al número de casos en países como México, donde ocupa el 4º lugar mundial de incidencia. La MAFLD se desarrolla en personas con sobrepeso u obesidad y se caracteriza por la acumulación de triglicéridos en el hígado, donde puede evolucionar hacia carcinoma hepatocelular. Se ha observado que la MAFLD depende de la genética y del estilo de vida. Tomando en cuenta la alta prevalencia de MAFLD en la población hispana, nos enfocamos en este trabajo en estudiar la prevalencia y características relacionadas con esta enfermedad en pacientes mexicanos. METODOS: En este estudio se incluyeron 572 pacientes con sobrepeso u obesidad, a los cuales se les realizó un análisis de cribado mediante el índice de hígado graso (IHG), se analizaron parámetros clínicos, demográficos y comorbilidades. Se obtuvieron frecuencias de las variables y se analizaron los datos mediante chi cuadrado o exacta de Fisher, razón de momios (OR) y regresión logística binaria. RESULTADOS: Se obtuvo una prevalencia del 37% de MAFLD, donde la historia familiar de obesidad, el uso de paracetamol, así como el consumo de carbohidratos y grasas fueron factores de riesgo para su desarrollo. Se encontró que la hipertensión arterial, la obesidad visceral y la hipertrigliceridemia también estaban asociados al desarrollo de la MAFLD. Por otro lado, el ejercicio fue un factor protector. CONCLUSIONES: Nuestros resultados ponen de manifiesto la necesidad de realizar estudios relacionados con las causalidades de la MAFLD en los pacientes mexicanos, principalmente en el uso del paracetamol.
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Hígado Graso , Hispánicos o Latinos , Humanos , Acetaminofén , México/epidemiología , Obesidad/complicaciones , Obesidad/epidemiología , Factores de Riesgo , España , Hígado Graso/etnologíaRESUMEN
One of the main forms of nitrogen assimilated by microorganisms and plants is ammonium, despite its toxicity at low millimolar concentrations. Ammonium absorption has been demonstrated to be carried out by highly selective plasma membrane-located transporters of the AMT/MEP/Rh family and characterized by the presence of a well conserved hydrophobic pore through which ammonia is proposed to move. However, uncertainties exist regarding the exact chemical species transported by these membrane proteins, which can be in the form of either hydrophobic ammonia or charged ammonium. Here, we present the characterization of PvAMT1;1 from the common bean and demonstrate that it mediates the high affinity (micromolar), rapidly saturating (1 mM) electrogenic transport of ammonium. Activity of the transporter is enhanced by low extracellular pH, and associated with this acidic pH stimulation are changes in the reversal potential and cytoplasm acidification, indicating that PvAMT1;1 functions as an H(+)/NH(4)(+) symporter. Mutation analysis of a unique histidine present in PvAMT1;1 (H125R) leads to the stimulation of ammonium transport by decreasing the K(m) value by half and by increasing the V(max) 3-fold, without affecting the pH dependence of the symporter. In contrast, mutation of the first conserved histidine within the channel modifies the properties of PvAMT1;1, increasing its K(m) and V(max) values and transforming it into a pH-independent mechanism.
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Proteínas de Transporte de Catión/metabolismo , Phaseolus/metabolismo , Proteínas de Plantas/metabolismo , Simportadores/metabolismo , Citoplasma , Fenómenos Electrofisiológicos , Concentración de Iones de Hidrógeno , Mutación , Compuestos de Amonio Cuaternario/farmacologíaRESUMEN
Extracellular vesicles (EVs) are membrane enclosures released by eukaryotic cells that carry bioactive molecules and serve to modulate biological responses in recipient cells. Both increased EV release and altered EV composition are associated with the development and progression of many pathologies including cancer. Hypoxia, a feature of rapidly growing solid tumours, increases the release of EVs. However, the molecular mechanisms remain unknown. The hypoxia inducible factors (HIFs) are transcription factors that act as major regulators of the cellular adaptations to hypoxia. Here, we investigated the requirement of HIF pathway activation for EV release in Human Embryonic Kidney Cells (HEK293). Time course experiments showed that EV release increased concomitantly with sustained HIF1α and HIF2α activation following the onset of hypoxia. shRNA mediated knock-down of HIF1α but not HIF2α abrogated the effect of hypoxia on EV release, suggesting HIF1α is involved in this process. However, stabilization of HIF proteins in normoxic conditions through: (i) heterologous expression of oxygen insensitive HIF1α or HIF2α mutants in normoxic cells or (ii) chemical inhibition of the prolyl hydroxylase 2 (PHD2) repressor protein, did not increase EV release, suggesting HIF activation alone is not sufficient for this process. Our findings suggest HIF1α plays an important role in the regulation of EV release during hypoxia in HEK293 cells, however other hypoxia triggered mechanisms likely contribute as stabilization of HIF1α alone in normoxia is not sufficient for EV release.
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Hipoxia de la Célula , Células Epiteliales/metabolismo , Vesículas Extracelulares/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Embrión de Mamíferos , Células Epiteliales/citología , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Riñón/citologíaRESUMEN
OBJECTIVE: High-risk (HR) prostate cancer (CaP) patients are at greatest risk for occult metastases and disease progression. Radical prostatectomy (RP) provides benefit, but remains of unknown oncologic value compared with other options. We investigated outcomes of RP for HR, very-high-risk (VHR), or metastatic CaP. METHODS: Included are 1,635 patients undergoing RP between January 2012 and December 2018 (prior to widespread availability of CaP-specific PET imaging). VHR CaP was defined as having ≥2HR features, >4cores of biopsy Gleason ≥4+4, or primary Gleason pattern 5. Metastatic CaP was defined by radiographic evidence of N1 and/or M1 CaP and grouped as cN1Many and cN0M1. Pre-treatment, perioperative, and early oncologic data were compared. Patient/tumor characteristics were compared according to risk groups using Chi-squared and Wilcoxon rank-sum tests. Kaplan-Meier analysis of cancer progression and multivariable analyses were performed. RESULTS: Length of stay >2days and readmission following RP was 10.8% and 5.5% for patients with HR or higher CaP. Median time to progression was 3.9 months (IQR:1.6-13.9), and 2-year progression-free probability was 67% for HR, 53% for VHR, 51% for cN1Many, and 58% for cN0M1. In multivariable analysis, VHR (hazard ratio:1.70; P < 0.0001) and cN1Many (1.96, P < 0.0001) were highly significant predictors of progression, while cN0M1 was not (P = 0.54), compared with non-metastatic HR CaP. Limitations include selection biases and imprecision of imaging methodologies. CONCLUSIONS: Most patients with HR or higher CaP remain progression-free 2 years after RP, with acceptable perioperative outcomes. Progression-free survival was similar in cN1 and VHR patients, better with non-metastatic HR CaP, and between these for cN0M1 patients indicating the imprecise clinical staging occurring with conventional imaging modalities alone.
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Música , Neoplasias de la Próstata , Humanos , Masculino , Clasificación del Tumor , Próstata/patología , Antígeno Prostático Específico , Prostatectomía/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/cirugía , Estudios RetrospectivosRESUMEN
Poor solubility and short biological half-life present a challenge that needs to be overcome in order to improve the recognized bioactivities of curcumin (CUR), the main phenolic compounds derived from the roots of Curcuma longa. However, drug delivery systems have proven to be an excellent strategy to improve and obtain greater bioavailability. Our previous studies on curcuminoid hybrid nanoparticles have shown promising results by significantly increasing the solubility of desmethoxycurcumin (DMC) and bisdemethoxycurcumin (BDM). In this contribution, we performed a detailed characterization of a CUR as well as in vitro and in vivo studies. The developed method produced CUR loaded nanoparticles with an average size of 49.46 ± 0.80. Moreover, the FT-IR analysis confirmed the encapsulation, and TEM images showed their spherical shape. The NP achieved an encapsulation efficiency greater than 99%. Further, the release studies found that the NPs obtained a significantly higher release than the pure compounds in water. In vivo delayed-type hypersensitivity (DTH) studies showed promising results by enhancing the immune activity response of CUR in NP compared to bulk CUR. Furthermore, we report a significant increase in antioxidant activity for CUR-NP in aqueous solution compared to free CUR. Finally, an important in vitro cytotoxic effect on gastric AGS and colon SW620 adenocarcinoma cell lines was found for CUR-NP while empty carrier nanoparticles are observed to exhibit low cytotoxicity, indicating the potential of these CUR-PLU NPs for further studies to assess their phytotherapeutic applications.
RESUMEN
Curcuma longa constitutes an important source of secondary metabolites that have been associated with multiple health benefits. For instance, curcumin, demethoxycurcumin and bisdemethoxycurcumin, have been found to perform important biological activities, such as anti-inflammatory, antioxidant, anticancer, antimicrobial, antihypertensive and anticoagulant. These promising results prompted this research to evaluate the polyphenols of C. longa rhizomes in Costa Rica. The present work reports a comprehensive study on the polyphenolic profile and the contents of the three main curcuminoids as well as the antioxidant activity of extracts from C. longa rhizomes (n = 12) produced in Costa Rica. Through UPLC-QTOF-ESI MS, a total of 33 polyphenols were identified, grouped in eight types of structures. In addition, our findings on the main curcuminoids using UPLC-DAD show all rhizomes complying with total curcuminoids (TC) content established by the United States Pharmacopeia (USP). At an individual level, samples NW-3 and NE-1 show the higher contents (118.7 and 125.0 mg/g dry material), representing more than twice the average values of the lowest samples. These samples also exhibit the highest Folin−Ciocalteu (FC) reducing capacity results as well as the best DPPH (IC50 15.21 and 16.07 µg extract/mL) and NO (IC50 between 52.5 and 54.3 µg extract/mL) antioxidant values. Further, Pearson correlation analysis findings indicated positive correlation (p < 0.05) between TC, CUR with FC results (r = 0.833 and r = 0.867 respectively) and negative correlation (p < 0.05) between CUR, TC and FC with DPPH results (r = −0.898, r = −0.911, and r = −0.890, respectively) and between NO results and DPPH (r = −0.805, p < 0.05). Finally, results for Principal Component Analysis (PCA) showed composition variability associated with their region of origin with products from the Northeastern (NE) region exhibiting higher average values for FC, TC and antioxidant activities. Further, PCA confirmed that two samples, namely NE-1 and NW-3, stand out by presenting the highest PC1 due to their particularly high TC, CUR and antioxidant activities. Consequently, our findings agree with previous results indicating the importance of C. longa extracts to elaborate products with potential benefits for health, while delivering extracts with higher levels of curcuminoids than previous reports and exhibiting high antioxidant activity.
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There are still questions about whether macrophage differentiation is predetermined or is induced in response to tissue microenvironments. C2D macrophage cells reside early in the macrophage lineage in vitro, but differentiate to a more mature phenotype after adoptive transfer to the peritoneal cavity (PEC-C2D). Since C2D macrophage cells also traffic to adipose tissue after adoptive transfer, we explored the impact of white adipose tissue (WAT), brown adipose tissue (BAT) and in vitro cultured adipocytes on C2D macrophage cells. When PEC-C2D macrophage cells were cultured with preadipocytes the cells stretched out and CD11b and Mac-2 expression was lower compared to PEC-C2D macrophage cells placed in vitro alone. In contrast, PEC-C2D cells co-cultured with adipocytes maintained smaller, round morphology and more cells expressed Mac-2 compared to PEC-C2D co-cultured with preadipocytes. After intraperitoneal injection, C2D macrophage cells migrated into both WAT and BAT. A higher percentage of C2D macrophage cells isolated from WAT (WAT-C2D) expressed Ly-6C (33%), CD11b (11%), Mac-2 (11%) and F4/80 (29%) compared to C2D macrophage cells isolated from BAT (BAT-C2D). Overall, BAT-C2D macrophage cells had reduced expression of many cytokine, chemokine and receptor gene transcripts when compared to in vitro grown C2D macrophages, while WAT-C2D macrophage cells and PEC-C2D up-regulated many of these gene transcripts. These data suggest that the C2D macrophage phenotype can change rapidly and distinct phenotypes are induced by different microenvironments.
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Adipocitos/citología , Tejido Adiposo Pardo/citología , Tejido Adiposo Blanco/citología , Macrófagos/citología , Células 3T3-L1 , Adipocitos/metabolismo , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Traslado Adoptivo , Animales , Antígeno CD11b/metabolismo , Diferenciación Celular , Línea Celular , Movimiento Celular , Tamaño de la Célula , Células Cultivadas , Técnicas de Cocultivo , Femenino , Citometría de Flujo , Galectina 3/metabolismo , Perfilación de la Expresión Génica , Interleucina-6/genética , Macrófagos/metabolismo , Macrófagos/trasplante , Masculino , Ratones , Ratones Endogámicos C57BL , Cavidad Peritoneal/citología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
The flatworm Taenia solium causes human and pig cysticercosis. When cysticerci are established in the human central nervous system, they cause neurocysticercosis, a potentially fatal disease. Neurocysticercosis is a persisting public health problem in rural regions of Mexico and other developing countries of Latin America, Asia, and Africa, where the infection is endemic. The great variability observed in the phenotypic and genotypic traits of cysticerci result in a great heterogeneity in the patterns of molecules secreted by them within their host. This work is aimed to identify and characterize cysticercal secretion proteins of T. solium cysticerci obtained from 5 naturally infected pigs from Guerrero, Mexico, using 2D-PAGE proteomic analysis. The isoelectric point (IP) and molecular weight (MW) of the spots were identified using the software ImageMaster 2D Platinum v.7.0. Since most secreted proteins are impossible to identify by mass spectrometry (MS) due to their low concentration in the sample, a novel strategy to predict their sequence was applied. In total, 108 conserved and 186 differential proteins were identified in five cysticercus cultures. Interestingly, we predicted the sequence of 14 proteins that were common in four out of five cysticercus cultures, which could be used to design vaccines or diagnostic methods for neurocysticercosis. A functional characterization of all sequences was performed using the algorithms SecretomeP, SignalP, and BlastKOALA. We found a possible link between signal transduction pathways in parasite cells and human cancer due to deregulation in signal transduction pathways. Bioinformatics analysis also demonstrated that the parasite release proteins by an exosome-like mechanism, which could be of biological interest.
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Cysticercus/metabolismo , Proteoma , Taenia solium/metabolismo , Animales , Cisticercosis/veterinaria , Electroforesis en Gel Bidimensional , Proteínas del Helminto/genética , Proteínas del Helminto/aislamiento & purificación , Análisis de Secuencia de Proteína , Transducción de Señal , Porcinos , Enfermedades de los Porcinos/parasitología , Taenia solium/genética , Taenia solium/crecimiento & desarrolloRESUMEN
Canine hyperadrenocorticism is a common endocrine disorder caused by chronic secretion of glucocorticoid, often associated with hypercoagulability and secondary thrombosis. The thrombin generation assay (TGA) evaluates hemostasis globally by measuring endogenous thrombin potential. We aimed to determine whether TGA is suitable for assessing hypercoagulability in dogs with endogenous hyperadrenocorticism (HAC), and to correlate TGA with coagulation markers including fibrinogen, antithrombin (AT), D-dimer, prothrombin time (PT) and activated partial thromboplastin time (aPTT), and with routine laboratory tests for elucidating prothrombotic mechanisms and evaluating their utility as hypercoagulability screening tests. Thrombin generation performed with high activator concentration showed significantly higher endogenous thrombin potential (ETP) (Pâ¯=â¯.0239) and peak thrombin (Pâ¯=â¯.0281) in Cushing patients. Fibrinogen (Pâ¯=â¯<.0001) and AT (Pâ¯=â¯.0444) activities were significantly higher in the HAC group, while those of PT (Pâ¯=â¯.0046) and aPTT (Pâ¯=â¯.0002) were lower. Basal cortisol levels correlated positively with fibrinogen (r = 0.4503; P = .0355) and negatively with AT activity (r = -0.4580; Pâ¯=â¯.0280). Fibrinogen and hematocrit values were inversely correlated (r = -0.4853; P = .0076). Our study confirmed the presence of higher thrombin generation in dogs with HAC. However, TGA performed with lower activator concentrations was unsuitable for detecting hypercoagulability. Higher AT and fibrinogen levels and lower aPTT activity were identified in dogs with HAC relative to controls suggesting a potential role for the combined use of these assays when assessing hypercoagulability in canine hyperadrenocorticism.