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1.
J Nutr ; 153(8): 2205-2215, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37247819

RESUMO

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.


Assuntos
Luteína , Mães , Feminino , Humanos , Lactente , Gravidez , Carotenoides , Suplementos Nutricionais , Estudos Prospectivos , Vitaminas , Zeaxantinas
2.
J Biol Chem ; 296: 100283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33450224

RESUMO

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.


Assuntos
Ácidos Graxos/metabolismo , Hepatoblastoma/metabolismo , Neoplasias Hepáticas/metabolismo , Enzima Bifuncional do Peroxissomo/genética , Animais , Ácidos Dicarboxílicos/efeitos adversos , Ácidos Dicarboxílicos/farmacologia , Ácidos Graxos/genética , Hepatoblastoma/genética , Hepatoblastoma/patologia , Humanos , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metabolismo/genética , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/metabolismo , Oxirredução , Peroxissomos/genética , Peroxissomos/metabolismo
3.
J Biol Chem ; 294(14): 5466-5486, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30755479

RESUMO

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.


Assuntos
Ciclo do Ácido Cítrico , Fibroblastos/metabolismo , Potencial da Membrana Mitocondrial , Consumo de Oxigênio , Complexo Piruvato Desidrogenase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Fibroblastos/patologia , Humanos , Complexo Piruvato Desidrogenase/metabolismo , Ratos , Ratos Mutantes
4.
J Biol Chem ; 294(46): 17524-17542, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31597698

RESUMO

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.


Assuntos
Hepatoblastoma/genética , Neoplasias Hepáticas/genética , beta Catenina/genética , Animais , Proliferação de Células , Hepatoblastoma/patologia , Neoplasias Hepáticas/patologia , Camundongos , Mutação , Ativação Transcricional , Transcriptoma
5.
Ophthalmol Sci ; 4(5): 100537, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39071916

RESUMO

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.

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