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1.
J Nutr ; 153(8): 2205-2215, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37247819

RESUMEN

BACKGROUND: Adding carotenoids, particularly lutein (L) and zeaxanthin (Z), to prenatal micronutrient formulations has been promoted to enhance infant visual and neural development and to maintain maternal health. Although these claims are biologically plausible, they are not yet supported by a compelling prospective trial. OBJECTIVE: We investigated the effect of prenatal carotenoid supplementation on biomarkers of maternal and infant systemic carotenoid status. METHODS: We randomly assigned 47 first trimester pregnant subjects by 1:1 allocation to receive standard-of-care prenatal vitamins plus a 10 mg L and 2 mg Z softgel (the Carotenoid group) or standard-of-care prenatal vitamins with a placebo softgel (the Control group) for 6-8 mo. Maternal carotenoid concentrations in the serum and skin at the end of each trimester and postpartum were measured with HPLC and resonance Raman spectroscopy, respectively. Infants' systemic carotenoid status was assessed using similar techniques but optimized for infants. Repeated measures and paired t-tests were determined, and a P value < 0.05 was considered statistically significant. RESULTS: After supplementation, there was a statistically significant increase in maternal serum L + Z concentrations, serum total carotenoid concentrations, and skin carotenoid status (P < 0.001 for all) in the Carotenoid group relative to the Control group at all study time points. Similarly, infants whose mothers were in the Carotenoid group had a significant 5-fold increase in cord blood L + Z concentrations, over a 3-fold increase in cord blood total carotenoids, and a 38% increase in skin carotenoids compared with the Control group (P < 0.0001 for all). In addition, there was a strong positive, statistically significant correlation between postpartum maternal and infant systemic carotenoid status (P < 0.0001). CONCLUSION: Prenatal carotenoid supplementation significantly increased maternal and infant systemic (skin and serum) carotenoid status, which may benefit pregnant women and their infants' health. This trial was registered at clinicaltrials.gov as NCT03750968.


Asunto(s)
Luteína , Madres , Femenino , Humanos , Lactante , Embarazo , Carotenoides , Suplementos Dietéticos , Estudios Prospectivos , Vitaminas , Zeaxantinas
2.
J Biol Chem ; 296: 100283, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33450224

RESUMEN

Metabolic reprogramming provides transformed cells with proliferative and/or survival advantages. Capitalizing on this therapeutically, however, has been only moderately successful because of the relatively small magnitude of these differences and because cancers may further adapt their metabolism to evade metabolic pathway inhibition. Mice lacking the peroxisomal bifunctional enzyme enoyl-CoA hydratase/3-hydroxyacyl CoA dehydrogenase (Ehhadh) and supplemented with the 12-carbon fatty acid lauric acid (C12) accumulate the toxic metabolite dodecanedioic acid (DDDA), which causes acute hepatocyte necrosis and liver failure. We noted that, in a murine model of pediatric hepatoblastoma (HB) and in primary human HBs, downregulation of Ehhadh occurs in association with the suppression of mitochondrial ß- and endosomal/peroxisomal ω-fatty acid oxidation pathways. This suggested that HBs might be more susceptible than normal liver tissue to C12 dietary intervention. Indeed, HB-bearing mice provided with C12- and/or DDDA-supplemented diets survived significantly longer than those on standard diets. In addition, larger tumors developed massive necrosis following short-term DDDA administration. In some HBs, the eventual development of DDDA resistance was associated with 129 transcript differences, ∼90% of which were downregulated, and approximately two-thirds of which correlated with survival in numerous human cancers. These transcripts often encoded extracellular matrix components, suggesting that DDDA resistance arises from reduced Ehhadh uptake. Lower Ehhadh expression was also noted in murine hepatocellular carcinomas and in subsets of certain human cancers, supporting the likely generality of these results. Our results demonstrate the feasibility of C12 or DDDA dietary supplementation that is nontoxic, inexpensive, and likely compatible with more standard chemotherapies.


Asunto(s)
Ácidos Grasos/metabolismo , Hepatoblastoma/metabolismo , Neoplasias Hepáticas/metabolismo , Enzima Bifuncional Peroxisomal/genética , Animales , Ácidos Dicarboxílicos/efectos adversos , Ácidos Dicarboxílicos/farmacología , Ácidos Grasos/genética , Hepatoblastoma/genética , Hepatoblastoma/patología , Humanos , Hígado/enzimología , Hígado/metabolismo , Hígado/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Metabolismo/genética , Ratones , Ratones Noqueados , Mitocondrias/genética , Mitocondrias/metabolismo , Oxidación-Reducción , Peroxisomas/genética , Peroxisomas/metabolismo
3.
J Biol Chem ; 294(14): 5466-5486, 2019 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-30755479

RESUMEN

Eukaryotic cell metabolism consists of processes that generate available energy, such as glycolysis, the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (Oxphos), and those that consume it, including macromolecular synthesis, the maintenance of ionic gradients, and cellular detoxification. By converting pyruvate to acetyl-CoA (AcCoA), the pyruvate dehydrogenase (PDH) complex (PDC) links glycolysis and the TCA cycle. Surprisingly, disrupting the connection between glycolysis and the TCA cycle by inactivation of PDC has only minor effects on cell replication. However, the molecular basis for this metabolic re-equilibration is unclear. We report here that CRISPR/Cas9-generated PDH-knockout (PDH-KO) rat fibroblasts reprogrammed their metabolism and their response to short-term c-Myc (Myc) oncoprotein overexpression. PDH-KO cells replicated normally but produced surprisingly little lactate. They also exhibited higher rates of glycolysis and Oxphos. In addition, PDH-KO cells showed altered cytoplasmic and mitochondrial pH, redox states, and mitochondrial membrane potential (ΔΨM). Conditionally activated Myc expression affected some of these parameters in a PDH-dependent manner. PDH-KO cells had increased oxygen consumption rates in response to glutamate, but not to malate, and were depleted in all TCA cycle substrates between α-ketoglutarate and malate despite high rates of glutaminolysis, as determined by flux studies with isotopically labeled glutamine. Malate and pyruvate were diverted to produce aspartate, thereby potentially explaining the failure to accumulate lactate. We conclude that PDH-KO cells maintain proliferative capacity by utilizing glutamine to supply high rates of AcCoA-independent flux through the bottom portion of the TCA cycle while accumulating pyruvate and aspartate that rescue their redox defects.


Asunto(s)
Ciclo del Ácido Cítrico , Fibroblastos/metabolismo , Potencial de la Membrana Mitocondrial , Consumo de Oxígeno , Complejo Piruvato Deshidrogenasa/genética , Animales , Línea Celular Tumoral , Proliferación Celular , Fibroblastos/patología , Humanos , Complejo Piruvato Deshidrogenasa/metabolismo , Ratas , Ratas Mutantes
4.
J Biol Chem ; 294(46): 17524-17542, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31597698

RESUMEN

Hepatoblastoma (HB) is the most common pediatric liver cancer. Although long-term survival of HB is generally favorable, it depends on clinical stage, tumor histology, and a variety of biochemical and molecular features. HB appears almost exclusively before the age of 3 years, is represented by seven histological subtypes, and is usually associated with highly heterogeneous somatic mutations in the catenin ß1 (CTNNB1) gene, which encodes ß-catenin, a Wnt ligand-responsive transcriptional co-factor. Numerous recurring ß-catenin mutations, not previously documented in HB, have also been identified in various other pediatric and adult cancer types. Little is known about the underlying factors that determine the above HB features and behaviors or whether non-HB-associated ß-catenin mutations are tumorigenic when expressed in hepatocytes. Here, we investigated the oncogenic properties of 14 different HB- and non-HB-associated ß-catenin mutants encoded by Sleeping Beauty vectors following their delivery into the mouse liver by hydrodynamic tail-vein injection. We show that all ß-catenin mutations, as well as WT ß-catenin, are tumorigenic when co-expressed with a mutant form of yes-associated protein (YAP). However, tumor growth rates, histologies, nuclear-to-cytoplasmic partitioning, and metabolic and transcriptional landscapes were strongly influenced by the identities of the ß-catenin mutations. These findings provide a context for understanding at the molecular level the notable biological diversity of HB.


Asunto(s)
Hepatoblastoma/genética , Neoplasias Hepáticas/genética , beta Catenina/genética , Animales , Proliferación Celular , Hepatoblastoma/patología , Neoplasias Hepáticas/patología , Ratones , Mutación , Activación Transcripcional , Transcriptoma
5.
Ophthalmol Sci ; 4(5): 100537, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39071916

RESUMEN

Purpose: Lutein (L) and zeaxanthin (Z) are xanthophyll carotenoids that have been promoted to enhance maternal health and infant visual and neurodevelopment. In this study, we determined the effects of prenatal L and Z supplementation on systemic and ocular carotenoid status in the mother and her newborn infant (NCT03750968). This report focuses on the ocular effects of prenatal carotenoid supplementation. Design: A prospective randomized clinical trial with 47 subjects randomly assigned by 1:1 allocation to receive standard-of-care prenatal vitamins along with 10 mg L and 2 mg Z softgel (Carotenoid Group) or standard-of-care prenatal vitamins with a placebo softgel (Control Group) starting in the first trimester. Subjects: We enrolled low-risk pregnancy subjects aged ≥18 years from the obstetrics and gynecology clinic of the University of Utah Hospital. Methods: Maternal macular, skin, and serum carotenoid concentrations were measured using autofluorescence imaging, resonance Raman spectroscopy, and high-performance liquid chromatography, respectively. Infants' ocular carotenoids and retinal architecture were measured by blue light reflectance imaging and spectral-domain OCT, respectively. Main Outcome Measures: Changes in maternal and infant macular pigment, skin, and serum carotenoid status over the study period. Differences in infants' retinal maturity indicators between the 2 study groups. Results: Following supplementation, there was a statistically significant increase in maternal macular pigment optical volume (P < 0.001) in the Carotenoid Group relative to the Control Group at all study time points, and there was no detectable maternal ocular carotenoid depletion. Infant skin and serum carotenoids increased significantly in the Carotenoid Group compared with the Control Group. As exploratory endpoints, infants in the Carotenoid Group had a 20% increase in macular pigment optical density (P = 0.242) and more mature foveal parameters compared with those in the Control Group. Conclusion: Prenatal carotenoid supplementation significantly increased maternal and infant systemic carotenoids and caused a pattern of increased infant ocular carotenoid status, which may benefit both mothers and their infants' ocular development and function. This study provides important data to design and power a future multicenter study of prenatal carotenoid supplementation in higher-risk pregnancies. Financial Disclosures: The author(s) have no proprietary or commercial interest in any materials discussed in this article.

6.
Phys Chem Chem Phys ; 15(26): 10885-94, 2013 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-23698702

RESUMEN

Geometrically well-defined Cu6Sn5 thin films were used as a model system to estimate the diffusion depth and diffusion pathway requirements of Na ions in alloy anodes. Cu6Sn5 anodes have an initial reversible capacity towards Li of 545 mA h g(-1) (Li3.96Sn or 19.8 Li/Cu6Sn5), close to the theoretical 586 mA h g(-1) (Li4.26Sn), and a very low initial irreversible capacity of 1.6 Li/Cu6Sn5 (Li0.32Sn). In contrast, the reaction with Na is limited with a reversible capacity of 160 mA h g(-1) compared to the expected 516 mA h g(-1) (Na3.75Sn). X-ray diffraction and (119)Sn-Mössbauer spectroscopy measurements show that this limited capacity likely results from the restricted diffusion of Na into the anode nanoparticles and not the formation of a low Na-content phase. Moreover, our results suggest that the η-Cu6Sn5 alloy should have optimized particle sizes of nearly 10 nm diameter to increase the Na capacity significantly. An alternative system consisting of a two-phase mixture of Cu6Sn5 and Sn of nominal composition 'Cu6Sn10' has been studied and is able to deliver a larger initial reversible storage capacity of up to 400 mA h g(-1). Finally, we have demonstrated that the presence of Cu in Cu6Sn5 and 'Cu6Sn10' suppresses the anomalous electrolyte decomposition normally observed for pure Sn.

7.
Cell Mol Gastroenterol Hepatol ; 12(1): 199-228, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33618031

RESUMEN

BACKGROUND & AIMS: Hepatoblastoma (HB), the most common pediatric liver cancer, often bears ß-catenin mutations and deregulates the Hippo tumor suppressor pathway. Murine HBs can be generated by co-expressing ß-catenin mutants and the constitutively active Hippo effector YAPS127A. Some HBs and other cancers also express mutants of NFE2L2/NRF2 (NFE2L2), a transcription factor that tempers oxidative and electrophilic stress. In doing so, NFE2L2 either suppresses or facilitates tumorigenesis. METHODS: We evaluated NFE2L2's role in HB pathogenesis by co-expressing all combinations of mutant ß-catenin, YAPS127A, and the patient-derived NFE2L2 mutants L30P and R34P in murine livers. We evaluated growth, biochemical and metabolic profiles, and transcriptomes of the ensuing tumors. RESULTS: In association with ß-catenin+YAPS127A, L30P and R34P markedly accelerated HB growth and generated widespread cyst formation and necrosis, which are otherwise uncommon features. Surprisingly, any 2 members of the mutant ß-catenin-YAPS127A-L30P/R34P triad were tumorigenic, thus directly establishing NFE2L2's oncogenicity. Each tumor group displayed distinct features but shared 22 similarly deregulated transcripts, 10 of which perfectly correlated with survival in human HBs and 17 of which correlated with survival in multiple adult cancers. One highly up-regulated transcript encoded serpin E1, a serine protease inhibitor that regulates fibrinolysis, growth, and extracellular matrix. Although the combination of mutant ß-catenin, YAPS127A, and serpin E1 did not accelerate cystogenic tumor growth, it did promote the widespread necrosis associated with mutant ß-catenin-YAPS127A-L30P/R34P tumors. CONCLUSIONS: Our findings establish the direct oncogenicity of NFE2L2 mutants and key transcripts, including serpin E1, that drive specific HB features.


Asunto(s)
Hepatoblastoma/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Animales , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Hepatoblastoma/patología , Humanos , Ratones , Mutación , Factor 2 Relacionado con NF-E2/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
8.
PLoS One ; 14(6): e0218186, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31242205

RESUMEN

In two different mouse liver cancer models, we recently showed that a switch from oxidative phosphorylation (Oxphos) to glycolysis (the Warburg effect) is invariably accompanied by a marked decline in fatty acid oxidation (FAO) and a reciprocal increase in the activity of pyruvate dehydrogenase (PDH), which links glycolysis to the TCA cycle. We now show that short-term implementation of either medium-chain (MC) or long-chain (LC) high fat diets (HFDs) nearly doubled the survival of mice with c-Myc oncoprotein-driven hepatocellular carcinoma (HCC). Mechanistically, HFDs forced tumors to become more reliant on fatty acids as an energy source, thus normalizing both FAO and PDH activities. More generally, both MC- and LC-HFDs partially or completely normalized the expression of 682 tumor-dysregulated transcripts, a substantial fraction of which are involved in cell cycle control, proliferation and metabolism. That these same transcripts were responsive to HFDs in livers strongly suggested that the changes were the cause of tumor inhibition rather than its consequence. In seven different human cancer cohorts, patients with tumors containing high ratios of FAO-related:glycolysis-related transcripts had prolonged survival relative to those with low ratios. Furthermore, in 13 human cancer types, the expression patterns of transcripts encoding enzymes participating in FAO and/or cholesterol biosynthesis also correlated with significantly prolonged survival. Collectively, our results support the idea that the survival benefits of HFDs are due to a reversal of the Warburg effect and other tumor-associated metabolic and cell cycle abnormalities. They also suggest that short-term dietary manipulation, either alone or in combination with more traditional chemotherapeutic regimens, might be employed as a relatively non-toxic and cost-effective means of enhancing survival in certain cancer types.


Asunto(s)
Neoplasias Hepáticas Experimentales/metabolismo , Animales , Línea Celular Tumoral , Dieta Alta en Grasa , Perfilación de la Expresión Génica , Glucólisis , Humanos , Neoplasias Hepáticas Experimentales/enzimología , Neoplasias Hepáticas Experimentales/genética , Ratones , Fosforilación Oxidativa , Proteínas Proto-Oncogénicas c-myc/metabolismo , Complejo Piruvato Deshidrogenasa/metabolismo , Transcripción Genética
9.
Przegl Epidemiol ; 62(2): 393-400, 2008.
Artículo en Polaco | MEDLINE | ID: mdl-18807486

RESUMEN

OBJECTIVE: To evaluate usefulness of total fluorescence of advanced glycation end products (AGE) and haptoglobin (Hp) measurement in human serum as parameters in liver cirrhosis and hepatocellular carcinoma development among patients with anti-HCV antibodies. MATERIALS AND METHODS: 43 patients (20 women and 23 men) with chronic hepatitis HCV were examined (14 individuals with liver cirrhosis and 9 with primary liver cancer). The control group numbers 20. As reflection of AGE concentration, total fluorescence in serum samples was measured with spectrofluorimetric method and haptoglobin with microplate guaiacol test. RESULTS: We affirmed that total fluorescence in examined groups was higher than in healthy subjects, but increase was not statistically significant. Fluorescence of AGE in serum from patients with hepatocellular carcinoma was lower in comparison to patients with cirrhosis and anti-HCV carriers. Haptoglobin was significantly decreased in serum of cirrhosis patients as compared to HCV carriers of patients with hepatocellular carcinoma (p < 0.001). CONCLUSIONS: The measurement of total fluorescence AGE is not differentiating for liver cirrhosis and hepatocellular carcinoma among anty-HCV carriers. We confirmed that haptoglobin, parameter included in fibrotest, is very useful, in detecting liver cirrhosis.


Asunto(s)
Carcinoma Hepatocelular/sangre , Productos Finales de Glicación Avanzada/sangre , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C Crónica/sangre , Cirrosis Hepática/sangre , Neoplasias Hepáticas/sangre , Anciano , Carcinoma Hepatocelular/virología , Estudios de Casos y Controles , Femenino , Hepatitis C Crónica/complicaciones , Humanos , Cirrosis Hepática/virología , Neoplasias Hepáticas/virología , Masculino , Persona de Mediana Edad , Polonia , Espectrometría de Fluorescencia/métodos
10.
Nanoscale ; 2(12): 2868-72, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20835448

RESUMEN

Novel α-alumina crystalline nanosheets are used for the preparation of alumina-carbon composites, in which the latter component is phenolic resin-based ordered mesoporous carbon. A unique feature of these composites is perpendicular orientation of ordered mesopores of the carbon to the (001) facets of nonporous α-alumina nanosheets accompanied by significant enlargement of these mesopores in comparison to those present in the bulk carbon.


Asunto(s)
Óxido de Aluminio/química , Carbono/química , Nanocompuestos/química , Cristalización , Nanocompuestos/ultraestructura , Porosidad , Difracción de Rayos X
11.
Chem Commun (Camb) ; 46(36): 6798-800, 2010 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-20717603

RESUMEN

Mesoporous composites of metal organic frameworks (MOFs) with boehmite and silica were prepared by one-pot microwave hydrothermal synthesis in the presence of Pluronic-type triblock-copolymer.

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