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1.
Chem Res Toxicol ; 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39361003

RESUMEN

6-PPD (N-[1,3-dimethylbutyl]-N'-phenyl-p-phenylenediamine) is an industrial antioxidant reported to be an environmental contaminant. It was found to be highly toxic to coho salmon and potentially other aquatic organisms. The toxicity of 6-PPD in humans, however, remains unknown. The neutrophil enzyme myeloperoxidase (MPO) is known to catalyze xenobiotic metabolism; therefore, its role in 6-PPD cytotoxicity was investigated using the MPO-rich HL-60 cell line. UV-visible spectroscopy and liquid chromatography-mass spectrometry (LC/MS) were performed to investigate the MPO-mediated oxidation of 6-PPD and identify possible metabolites in the absence and presence of glutathione (GSH). 6-PPD's cytotoxicity, effect on mitochondrial membrane potential (MMP), and GSH-depleting ability in HL-60 cells were assessed. Electron paramagnetic resonance (EPR) was used to determine GSH radical formation using DMPO, and mitochondrial-derived superoxide was assessed with the mito-TEMPO-H probe. Evaluation of the 6-PPD-induced cellular injury pathways was performed by preincubating an antioxidant and an MPO inhibitor with HL-60 cells. UV-vis analysis of MPO-catalyzed oxidation of 6-PPD demonstrated changes in the 6-PPD spectrum, whereas the addition of GSH altered the spectrum, indicating possible GSH conjugate formation. LC/MS showed the formation of multiple products, including GSH-6-PPD conjugates and a GSH conjugate to a 4-hydroxydiphenylamine (a known 6-PPD degradant), which could potentially induce cytotoxicity. 6-PPD demonstrated concentration-dependent cytotoxicity, and cellular GSH levels were decreased by 6-PPD. Similarly, the level of MMP decreased, suggesting mitochondrial depolarization. Furthermore, the EPR spin probe for mitochondrial superoxide showed a positive relationship with 6-PPD concentration, and EPR spin-trapping demonstrated 6-PPD concentration-dependent GSH radical signal intensity using MPO/H2O2. The GSH precursor, NAC, demonstrated partial cytoprotection against 6-PPD; however, the MPO inhibitor PF-1355 surprisingly showed no significant cytoprotective effect. Our results suggest that MPO could be a potential catalyst for 6-PPD toxicity in humans. However, MPO inhibition did not significantly affect cellular viability, suggesting an MPO-independent toxicity pathway. These findings warrant a deeper investigation to determine 6-PPD mammalian toxicity pathways.

2.
Eur Biophys J ; 53(4): 171-181, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38597963

RESUMEN

Polymeric micelles are nanocarriers for drug, protein and gene delivery due to their unique core/shell structure, which encapsulates and protects therapeutic cargos with diverse physicochemical properties. However, information regarding the micellar nanoenvironment's fluidity can provide unique insight into their makeup. In this study, we used electron paramagnetic resonance (EPR) spectroscopy to study free radical spin probe (5-doxylstearate methyl ester, 5-MDS, and 16-doxylstearic acid, 16-DS) behaviour in methoxy-poly(ethylene oxide)-poly(α-benzyl carboxylate-ε-caprolactone) (PEO-PBCL) and methoxy-poly(ethylene oxide)-poly(ε-caprolactone) (PEO-PCL) polymeric micelles. Spin probes provided information about the spectroscopic rotational correlation time (τ, s) and the spectroscopic partition parameter F. We hypothesized that spin probes would partition into the polymeric micelles, and these parameters would be calculated. The results showed that both 5-MDS and 16-DS spectra were modulated in the presence of polymeric micelles. Based on τ values, 5-MDS revealed that PEO-PCL (τ = 3.92 ± 0.26 × 10-8 s) was more fluid than PEO-PBCL (τ = 7.15 ± 0.63 × 10-8 s). The F parameter, however, could not be calculated due to the rotational hindrance of the probe within the micelles. With 16-DS, more probe rotation was observed, and although the F parameter could be calculated, it was not helpful to distinguish the micelles' fluidity. Also, doxorubicin-loading interfered with the spin probes, particularly for 16-DS. However, using simulations, we could distinguish the hydrophilic and hydrophobic components of the 16-DS probe. The findings suggest that EPR spectroscopy is a valuable method for determining core fluidity in polymeric micelles.


Asunto(s)
Micelas , Espectroscopía de Resonancia por Spin del Electrón/métodos , Poliésteres/química , Polietilenglicoles/química , Marcadores de Spin , Polímeros/química
3.
BMC Biotechnol ; 23(1): 44, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37817108

RESUMEN

Target identification is an essential part of the drug discovery and development process, and its efficacy plays a crucial role in the success of any given therapy. Although protein target identification research can be challenging, two main approaches can help researchers make significant discoveries: affinity-based pull-down and label-free methods. Affinity-based pull-down methods use small molecules conjugated with tags to selectively isolate target proteins, while label-free methods utilize small molecules in their natural state to identify targets. Target identification strategy selection is essential to the success of any drug discovery process and must be carefully considered when determining how to best pursue a specific project. This paper provides an overview of the current target identification approaches in drug discovery related to experimental biological assays, focusing primarily on affinity-based pull-down and label-free approaches, and discusses their main limitations and advantages.


Asunto(s)
Descubrimiento de Drogas , Proteínas , Proteínas/metabolismo
4.
Crit Rev Food Sci Nutr ; : 1-19, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37203963

RESUMEN

To achieve a more sustainable global food production, a shift from animal to plant protein based food is necessary. At the same time, these plant proteins are preferentially derived from side-streams of industrial processes. Wheat bran and germ represent two major side-streams of the wheat milling industry, and contain aqueous-phase soluble proteins with a well-balanced amino acid composition. To successfully use wheat bran and germ proteins in novel plant-based liquid and semi-solid foods, they need to (i) be rendered extractable and (ii) contribute functionally to stabilizing the food system. Prior heat treatment and the occurrence of intact cell walls are important barriers in this regard. Several strategies have been applied to overcome these issues, including physical processing and (bio)chemical modification. We here present a comprehensive, critical overview of the aqueous-phase extraction of protein from (modified) wheat bran and germ. Moreover, we discuss the functionality of the extracted protein, specifically in the context of liquid (foam- and emulsion-type) and semi-solid (gel-type) food applications. In each section, we identify important knowledge gaps and highlight several future prospects that could further increase the application potential of wheat bran and germ proteins in the food industry.

5.
Compr Rev Food Sci Food Saf ; 22(3): 1517-1554, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36815740

RESUMEN

A shift from animal protein- to plant protein-based foods is crucial in transitioning toward a more sustainable global food system. Among food products typically stabilized by animal proteins, food foams represent a major category. Wheat proteins are ubiquitous and structurally diverse, which offers opportunities for exploiting them for food foam and air-water interface stabilization. Notably, they are often classified into those that are soluble in aqueous systems (albumins and globulins) and those that are not (gliadins and glutenins). However, gliadins are at least to an extent water extractable and thus surface active. We here provide a comprehensive overview of studies investigating the air-water interfacial and foaming properties of the different wheat protein fractions. Characteristics in model systems are related to the functional role that wheat proteins play in gas cell stabilization in existing wheat-based foods (bread dough, cake batter, and beer foam). Still, to further extend the applicability of wheat proteins, and particularly the poorly soluble glutenins, to other food foams, their modification is required. Different physical, (bio)chemical, and other modification strategies that have been utilized to alter the solubility and therefore the air-water interfacial and foaming properties of the gluten protein fraction are critically reviewed. Such approaches may open up new opportunities for the application of (modified) gluten proteins in other food products, such as plant-based meringues, whippable drinks, or ice cream. In each section, important knowledge gaps are highlighted and perspectives for research efforts that could lead to the rational design of wheat protein systems with enhanced functionality and overall an increased applicability in food industry are proposed.


Asunto(s)
Triticum , Agua , Animales , Triticum/química , Agua/química , Gliadina/química , Gliadina/metabolismo , Proteínas de Plantas , Pan
6.
Chem Res Toxicol ; 35(6): 1001-1010, 2022 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-35575633

RESUMEN

The atypical antipsychotic drugs, quetiapine and clozapine, are associated with idiosyncratic drug reactions (such as agranulocytosis or neutropenia) that are thought to involve reactive metabolites. Neutrophil myeloperoxidase (MPO) metabolism of quetiapine is not well-studied, but is metabolized by cytochrome P450. Based on structural similarity to clozapine, we hypothesized that quetiapine can be metabolized by MPO and that there is overlap between cytochrome P450 and MPO metabolism of quetiapine. The interaction of quetiapine and clozapine with MPO and MPO chlorination activity was studied using UV-vis spectrophotometry. The metabolites were characterized using liquid chromatography-mass spectrometry (LC-MS), and electron paramagnetic resonance (EPR) spectroscopy was used for detecting drug-catalyzed glutathione oxidation. In the presence of quetiapine, MPO compound II accumulated for about 7.5 min, whereas in the presence of clozapine, MPO compound II was not observed as it was rapidly reduced back to the resting state. Increasing quetiapine concentrations resulted in a decrease in MPO chlorination activity, while the opposite result was found in the case of clozapine. UV-vis spectral studies showed no change when quetiapine was oxidized in the absence and presence of chloride anion (Cl-, to catalyze chlorination reactions). Significant changes, however, were observed in the same assay with clozapine, where Cl- appeared to hinder the rate of clozapine metabolism. The MPO-catalyzed hydroxylated and dealkylated metabolites of quetiapine and hydroxylated metabolites of clozapine were observed from the LC-MS analyses, particularly when Cl- was included in the reaction. In addition, hydroxylated, dealkylated, and a proposed sulfoxide metabolite of quetiapine were also observed in the reaction catalyzed by human microsomes/NADPH. Lastly, compared to quetiapine, clozapine metabolism by MPO/H2O2 and glutathione produced more glutathionyl radicals using EPR spin trapping. In conclusion, MPO/H2O2/Cl- was shown to metabolize quetiapine to S-oxidation and P450-like dealkylation products, and quetiapine metabolites were generally less reactive than clozapine.


Asunto(s)
Clozapina , Clozapina/metabolismo , Clozapina/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Desmetilación , Glutatión/metabolismo , Humanos , Peróxido de Hidrógeno , Neutrófilos/metabolismo , Peroxidasa/metabolismo , Fumarato de Quetiapina
7.
Compr Rev Food Sci Food Saf ; 20(4): 3881-3917, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34056854

RESUMEN

Proper gas cell stability during fermentation and baking is essential to obtain high-quality bread. Gas cells in wheat dough are stabilized by the gluten network formed during kneading and, from the moment this network locally ruptures, by liquid films containing nonstarch polysaccharides (NSPs) and surface-active proteins and lipids. Dough liquor (DL), the supernatant after ultracentrifugation of dough, is a model system for these liquid films and has been extensively studied mostly in the context of wheat bread making. Nonwheat breads are often of lower quality (loaf volume and crumb structure) than wheat breads because their doughs/batters lack a viscoelastic wheat gluten network. Therefore, gas cell stabilization by liquid film constituents may be more important in nonwheat than in wheat bread making. This manuscript aims to review the knowledge on DL/batter liquor (BL) and its relevance for studying gas cell stabilization in wheat and nonwheat (rye and oat) bread making. To this end, the unit operations in wheat, rye, and oat bread making are described with emphasis on gas incorporation and gas cell (de)stabilization. A discussion of the knowledge on the recoveries and chemical structures of proteins, lipids, and NSPs in DLs/BLs is provided and key findings of studies dealing with foaming and air-water interfacial properties of DL/BL are discussed. Next, the extent to which DL/BL functionality can be related to bread properties is addressed. Finally, the extent to which DL/BL is a representative model system for the aqueous phase of dough/batter is discussed and related to knowledge gaps and further research opportunities.


Asunto(s)
Pan , Triticum , Avena , Secale , Agua
8.
Annu Rev Genomics Hum Genet ; 17: 1-15, 2016 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-27147253

RESUMEN

It is my great pleasure to have been asked by the Editorial Committee of the Annual Review of Genomics and Human Genetics to write a short autobiography of my life in genetics over the past 70 years. It has been a great adventure. I came both to America and to human genetics by a circuitous and ultimately very fortunate route. I hope the next generation of geneticists will enjoy reading about it.


Asunto(s)
Genética Médica/historia , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Estados Unidos
9.
Arch Biochem Biophys ; 664: 15-23, 2019 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-30682330

RESUMEN

Isoniazid (INH) is one of the oldest drugs for the treatment of tuberculosis (TB) and is of continual clinical and research interest. The aim of the current study is to investigate the ability of INH to induce monocyte differentiation and the underlying signaling pathway involved in this phenomenon using HL-60 cells. In this study, HL-60 cells were treated with different non-cytotoxic concentrations of INH or vitamin D (a well-known inducer of monocytic differentiation) to determine key functional changes in the phenotype of these cells using several biochemical and cytobiological experiments. HL-60 cells are derived from human promyelocytic leukemia and bear some resemblance to promyelocytes, which differentiate into various cell types. INH-induced differentiation was confirmed to occur in a concentration-dependent manner through several functional markers such as nonspecific esterase activity, NADPH oxidase activity and expression of surface markers CD14 and CD16 (characteristic of monocytes). INH-induced monocytic-like differentiation in HL-60 cells and demonstrated that at least 25% of cells were differentiated within the range of the pharmacological concentrations of INH. To determine the effects of INH on HL-60 cells, we applied quantitative proteomics that revealed 32 proteins were altered significantly in pathways that could involve differentiation signals. Lastly, INH activated the ERK-1/MAPK signaling pathway based on detection of phosphorylated ERK-1. These in vitro findings in HL-60 cells warrant further study using promyelocytes or hematopoietic stem cells to evaluate the physiological capability of INH to induce monocytic differentiation that may aid in host defense against TB.


Asunto(s)
Isoniazida/farmacología , Monocitos/citología , Monocitos/efectos de los fármacos , Fenotipo , Supervivencia Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Células HL-60 , Humanos , Receptores de Lipopolisacáridos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Monocitos/metabolismo , NADPH Oxidasas/metabolismo , Receptores de IgG/metabolismo
10.
Am J Hum Genet ; 97(4): 512-20, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26365338

RESUMEN

Hereditary hemochromatosis (HH) is a common autosomal-recessive disorder associated with pathogenic HFE variants, most commonly those resulting in p.Cys282Tyr and p.His63Asp. Recommendations on returning incidental findings of HFE variants in individuals undergoing genome-scale sequencing should be informed by penetrance estimates of HH in unselected samples. We used the eMERGE Network, a multicenter cohort with genotype data linked to electronic medical records, to estimate the diagnostic rate and clinical penetrance of HH in 98 individuals homozygous for the variant coding for HFE p.Cys282Tyr and 397 compound heterozygotes with variants resulting in p.[His63Asp];[Cys282Tyr]. The diagnostic rate of HH in males was 24.4% for p.Cys282Tyr homozygotes and 3.5% for compound heterozygotes (p < 0.001); in females, it was 14.0% for p.Cys282Tyr homozygotes and 2.3% for compound heterozygotes (p < 0.001). Only males showed differences across genotypes in transferrin saturation levels (100% of homozygotes versus 37.5% of compound heterozygotes with transferrin saturation > 50%; p = 0.003), serum ferritin levels (77.8% versus 33.3% with serum ferritin > 300 ng/ml; p = 0.006), and diabetes (44.7% versus 28.0%; p = 0.03). No differences were found in the prevalence of heart disease, arthritis, or liver disease, except for the rate of liver biopsy (10.9% versus 1.8% [p = 0.013] in males; 9.1% versus 2% [p = 0.035] in females). Given the higher rate of HH diagnosis than in prior studies, the high penetrance of iron overload, and the frequency of at-risk genotypes, in addition to other suggested actionable adult-onset genetic conditions, opportunistic screening should be considered for p.[Cys282Tyr];[Cys282Tyr] individuals with existing genomic data.


Asunto(s)
Variación Genética/genética , Hemocromatosis/epidemiología , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Proteínas de la Membrana/genética , Adulto , Anciano , Sustitución de Aminoácidos , Niño , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Genotipo , Hemocromatosis/diagnóstico , Proteína de la Hemocromatosis , Heterocigoto , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Penetrancia , Pronóstico , Estados Unidos/epidemiología
11.
Blood ; 127(11): 1375, 2016 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-26989183

RESUMEN

To study erythropoiesis and anemia, one must have a firm foundation of indices that accurately measure red blood cell production and destruction. This paper, authored by hematology legends Arno G. Motulsky and Clement A. Finch, provides that foundation. Using methods that would not be approved in today's environment, the authors studied a cohort of normal healthy patients and an equal number of patients with different forms of anemia. The results confirm a reciprocal model of red cell production and destruction, show that anemia can be the result of either underproduction (a regenerative anemia or ineffective erythropoiesis) or increased destruction, and define parameters for distinguishing these 2 possibilities that are still widely used today.


Asunto(s)
Anemia/historia , Eritropoyesis , Hematología/historia , Anemia/fisiopatología , Envejecimiento Eritrocítico , Volumen de Eritrocitos , Historia del Siglo XX , Humanos
12.
Environ Sci Technol ; 52(5): 2898-2908, 2018 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-29420883

RESUMEN

Halobenzoquinones (HBQs) are a class of emerging disinfection byproducts. Chronic exposure to chlorinated drinking water is potentially associated with an increased risk of human bladder cancer. HBQ-induced cytotoxicity involves depletion of cellular glutathione (GSH), but the underlying mechanism remains unclear. Here we used ultrahigh performance liquid chromatography-high resolution mass spectrometry and electron paramagnetic resonance spectroscopy to study interactions between HBQs and GSH and found that HBQs can directly react with GSH, forming various glutathionyl conjugates (HBQ-SG) in both aqueous solution and HepG2 cells. We found that the formation of HBQ-SG varies with the initial molar ratio of GSH to HBQ in reaction mixtures. Higher molar ratios of GSH to HBQ facilitate the conjugation of more GSH molecules to an HBQ molecule. We deduced the reaction mechanism between GSH and HBQs, which involves redox cycling-induced formation of halosemiquinone (HSQ) free radicals and glutathione disulfide, Michael addition, as well as nucleophilic substitution. The proposed reaction rates are in the following order: formation of HSQ radicals > substitution of bromine by GSH > Michael addition of GSH on the benzoquinone ring > substitution of chlorine by GSH > substitution of the methyl group by GSH. The conjugates identified in HBQ-treated HepG2 cells were the same as those found in aqueous solution containing a 5:1 ratio of GSH:HBQs.


Asunto(s)
Agua Potable , Glutatión , Desinfección , Células Hep G2 , Humanos , Espectrometría de Masas en Tándem
13.
Mol Cell Biochem ; 429(1-2): 151-165, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28251434

RESUMEN

Numerous experimental studies have demonstrated the role of cytochrome P450 1B1 (CYP1B1) and its associated mid-chain hydroxyeicosatetraenoic acids (mid-chain HETEs) metabolite in the pathogenesis of cardiac hypertrophy. However, the ability of isoproterenol (ISO) to induce cardiac hypertrophy through mid-chain HETEs has not been investigated yet. Therefore, we hypothesized that ISO induces cardiac hypertrophy through the induction of CYP1B1 and its associated mid-chain HETE metabolites. To test our hypothesis, Sprague-Dawley rats were treated with ISO (5 mg/kg i.p.) for 12 and 72 h whereas, human ventricular cardiomyocytes RL-14 cells were exposed to 100 µM ISO in the presence and absence of 0.5 µM tetramethoxystilbene (TMS) a selective CYP1B1 inhibitor, or 25 nM CYP1B1-siRNA. Moreover, RL-14 cells were transiently transfected with the CRISPR-CYP1B1 plasmid. Thereafter, real-time PCR, western blot analysis, and liquid chromatography-electrospray ionization mass spectroscopy were used to determine the level of gene expression, protein expression, and mid-chain HETEs, respectively. Our results showed that ISO induced CYP1B1 protein expression and the level of cardiac mid-chain HETEs in vivo at pre-hypertrophic and hypertrophic stage. In vitro, inhibition of CYP1B1 using TMS or CYP1B1-siRNA significantly attenuates ISO-induced hypertrophy. Furthermore, overexpression of CYP1B1 significantly induced cellular hypertrophy and mid-chain HETEs metabolite. Mechanistically, the protective effect of TMS against cardiac hypertrophy was mediated through the modulation of superoxide anion, mitogen-activated protein kinases (MAPKs), and nuclear factor-κB (NF-κB). In conclusion, our study provides the first evidence that CYP1B1 and its associated mid-chain HETE metabolites are directly involved in the ISO-induced cardiac hypertrophy.


Asunto(s)
Cardiomegalia/metabolismo , Citocromo P-450 CYP1B1/metabolismo , Ácidos Hidroxieicosatetraenoicos/metabolismo , Isoproterenol/efectos adversos , Animales , Cardiomegalia/inducido químicamente , Cardiomegalia/genética , Línea Celular , Citocromo P-450 CYP1B1/genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Ratas , Ratas Sprague-Dawley
14.
Nature ; 470(7334): 382-5, 2011 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-21331040

RESUMEN

Interest in attributing the risk of damaging weather-related events to anthropogenic climate change is increasing. Yet climate models used to study the attribution problem typically do not resolve the weather systems associated with damaging events such as the UK floods of October and November 2000. Occurring during the wettest autumn in England and Wales since records began in 1766, these floods damaged nearly 10,000 properties across that region, disrupted services severely, and caused insured losses estimated at £1.3 billion (refs 5, 6). Although the flooding was deemed a 'wake-up call' to the impacts of climate change at the time, such claims are typically supported only by general thermodynamic arguments that suggest increased extreme precipitation under global warming, but fail to account fully for the complex hydrometeorology associated with flooding. Here we present a multi-step, physically based 'probabilistic event attribution' framework showing that it is very likely that global anthropogenic greenhouse gas emissions substantially increased the risk of flood occurrence in England and Wales in autumn 2000. Using publicly volunteered distributed computing, we generate several thousand seasonal-forecast-resolution climate model simulations of autumn 2000 weather, both under realistic conditions, and under conditions as they might have been had these greenhouse gas emissions and the resulting large-scale warming never occurred. Results are fed into a precipitation-runoff model that is used to simulate severe daily river runoff events in England and Wales (proxy indicators of flood events). The precise magnitude of the anthropogenic contribution remains uncertain, but in nine out of ten cases our model results indicate that twentieth-century anthropogenic greenhouse gas emissions increased the risk of floods occurring in England and Wales in autumn 2000 by more than 20%, and in two out of three cases by more than 90%.


Asunto(s)
Desastres/estadística & datos numéricos , Inundaciones/estadística & datos numéricos , Efecto Invernadero/estadística & datos numéricos , Actividades Humanas , Lluvia , Inglaterra , Calentamiento Global/estadística & datos numéricos , Modelos Teóricos , Medición de Riesgo , Ríos , Estaciones del Año , Gales
15.
Hum Mol Genet ; 23(13): 3513-22, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24516071

RESUMEN

Mitochondria integrate metabolic networks for maintaining bioenergetic requirements. Deregulation of mitochondrial metabolic networks can lead to mitochondrial dysfunction, which is a common hallmark of many diseases. Reversible post-translational protein acetylation modifications are emerging as critical regulators of mitochondrial function and form a direct link between metabolism and protein function, via the metabolic intermediate acetyl-CoA. Sirtuins catalyze protein deacetylation, but how mitochondrial acetylation is determined is unclear. We report here a mechanism that explains mitochondrial protein acetylation dynamics in vivo. Food withdrawal in mice induces a rapid increase in hepatic protein acetylation. Furthermore, using a novel LC-MS/MS method, we were able to quantify protein acetylation in human fibroblasts. We demonstrate that inducing fatty acid oxidation in fibroblasts increases protein acetylation. Furthermore, we show by using radioactively labeled palmitate that fatty acids are a direct source for mitochondrial protein acetylation. Intriguingly, in a mouse model that resembles human very-long chain acyl-CoA dehydrogenase (VLCAD) deficiency, we demonstrate that upon food-withdrawal, hepatic protein hyperacetylation is absent. This indicates that functional fatty acid oxidation is necessary for protein acetylation to occur in the liver upon food withdrawal. Furthermore, we now demonstrate that protein acetylation is abundant in human liver peroxisomes, an organelle where acetyl-CoA is solely generated by fatty acid oxidation. Our findings provide a mechanism for metabolic control of protein acetylation, which provides insight into the pathophysiogical role of protein acetylation dynamics in fatty acid oxidation disorders and other metabolic diseases associated with mitochondrial dysfunction.


Asunto(s)
Acetilcoenzima A/metabolismo , Ácidos Grasos/metabolismo , Acetilación , Animales , Western Blotting , Cromatografía Liquida , Electroforesis en Gel de Poliacrilamida , Fibroblastos/metabolismo , Humanos , Inmunoprecipitación , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Oxidación-Reducción , Peroxisomas/metabolismo , Espectrometría de Masas en Tándem
16.
Am J Hum Genet ; 93(6): 1035-45, 2013 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-24268658

RESUMEN

Hypertriglyceridemia (HTG) is a heritable risk factor for cardiovascular disease. Investigating the genetics of HTG may identify new drug targets. There are ~35 known single-nucleotide variants (SNVs) that explain only ~10% of variation in triglyceride (TG) level. Because of the genetic heterogeneity of HTG, a family study design is optimal for identification of rare genetic variants with large effect size because the same mutation can be observed in many relatives and cosegregation with TG can be tested. We considered HTG in a five-generation family of European American descent (n = 121), ascertained for familial combined hyperlipidemia. By using Bayesian Markov chain Monte Carlo joint oligogenic linkage and association analysis, we detected linkage to chromosomes 7 and 17. Whole-exome sequence data revealed shared, highly conserved, private missense SNVs in both SLC25A40 on chr7 and PLD2 on chr17. Jointly, these SNVs explained 49% of the genetic variance in TG; however, only the SLC25A40 SNV was significantly associated with TG (p = 0.0001). This SNV, c.374A>G, causes a highly disruptive p.Tyr125Cys substitution just outside the second helical transmembrane region of the SLC25A40 inner mitochondrial membrane transport protein. Whole-gene testing in subjects from the Exome Sequencing Project confirmed the association between TG and SLC25A40 rare, highly conserved, coding variants (p = 0.03). These results suggest a previously undescribed pathway for HTG and illustrate the power of large pedigrees in the search for rare, causal variants.


Asunto(s)
Exoma , Estudios de Asociación Genética , Ligamiento Genético , Hipertrigliceridemia/genética , Proteínas de Transporte de Membrana Mitocondrial/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Cromosomas Humanos Par 17 , Cromosomas Humanos Par 7 , Femenino , Predisposición Genética a la Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hipertrigliceridemia/metabolismo , Masculino , Persona de Mediana Edad , Fenotipo , Polimorfismo de Nucleótido Simple , Triglicéridos/sangre , Adulto Joven
17.
Am J Hum Genet ; 93(4): 631-40, 2013 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-24055113

RESUMEN

The incorporation of genomics into medicine is stimulating interest on the return of incidental findings (IFs) from exome and genome sequencing. However, no large-scale study has yet estimated the number of expected actionable findings per individual; therefore, we classified actionable pathogenic single-nucleotide variants in 500 European- and 500 African-descent participants randomly selected from the National Heart, Lung, and Blood Institute Exome Sequencing Project. The 1,000 individuals were screened for variants in 114 genes selected by an expert panel for their association with medically actionable genetic conditions possibly undiagnosed in adults. Among the 1,000 participants, 585 instances of 239 unique variants were identified as disease causing in the Human Gene Mutation Database (HGMD). The primary literature supporting the variants' pathogenicity was reviewed. Of the identified IFs, only 16 unique autosomal-dominant variants in 17 individuals were assessed to be pathogenic or likely pathogenic, and one participant had two pathogenic variants for an autosomal-recessive disease. Furthermore, one pathogenic and four likely pathogenic variants not listed as disease causing in HGMD were identified. These data can provide an estimate of the frequency (∼3.4% for European descent and ∼1.2% for African descent) of the high-penetrance actionable pathogenic or likely pathogenic variants in adults. The 23 participants with pathogenic or likely pathogenic variants were disproportionately of European (17) versus African (6) descent. The process of classifying these variants underscores the need for a more comprehensive and diverse centralized resource to provide curated information on pathogenicity for clinical use to minimize health disparities in genomic medicine.


Asunto(s)
Enfermedad/genética , Exoma , Predisposición Genética a la Enfermedad , Hallazgos Incidentales , Polimorfismo de Nucleótido Simple , Bases de Datos Genéticas , Frecuencia de los Genes , Humanos , Penetrancia
18.
Bioorg Med Chem Lett ; 26(5): 1411-5, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26850006

RESUMEN

Resveratrol is a natural compound with a plethora of activities as well as limitations. We recently reported a series of resveratrol-salicylate analogs with potential chemopreventive activity. Herein, we report the anti-inflammatory and antioxidant properties of these resveratrol derivatives. Using an in vitro COX inhibition assay, and two in vivo protocols (carrageenan-induced peritonitis and paw edema), we identified a novel compound (C10) as a potent anti-inflammatory agent. The enhanced potency of C10 was associated with the ability of C10 to decrease the activity of myeloperoxidase (MPO) enzyme at 10mg/kg, whereas resveratrol and it's natural analog (TMS) did not exert the same effect. Additionally, C10 significantly reduced the concentration of intracellular reactive oxygen species. Because of the proven association between cancer, inflammation, and oxidative stress, we believe that C10 is a promising chemopreventive molecule.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antioxidantes/farmacología , Edema/tratamiento farmacológico , Peritonitis/tratamiento farmacológico , Salicilatos/farmacología , Estilbenos/farmacología , Administración Oral , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Antioxidantes/síntesis química , Antioxidantes/química , Carragenina , Inhibidores de la Ciclooxigenasa/síntesis química , Inhibidores de la Ciclooxigenasa/química , Inhibidores de la Ciclooxigenasa/farmacología , Relación Dosis-Respuesta a Droga , Células Hep G2 , Humanos , Peróxido de Hidrógeno/antagonistas & inhibidores , Peróxido de Hidrógeno/farmacología , Ratones , Estructura Molecular , Estrés Oxidativo/efectos de los fármacos , Prostaglandina-Endoperóxido Sintasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Resveratrol , Salicilatos/química , Estilbenos/administración & dosificación , Estilbenos/química , Relación Estructura-Actividad
19.
J Sci Food Agric ; 96(3): 757-63, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25704643

RESUMEN

BACKGROUND: There is a growing interest in texturally and nutritionally satisfying vegetable alternatives to meat. Wheat gluten proteins have unique functional properties but a poor nutritional value in comparison to animal proteins. This study investigated the potential of egg white and bovine milk casein with well-balanced amino acid composition to increase the quality of wheat gluten-based protein-rich foods. RESULTS: Heating a wheat gluten (51.4 g)-water (100.0 mL) blend for 120 min at 100 °C increased its firmness less than heating a wheat gluten (33.0 g)-freeze-dried egg white (16.8 g)-water (100.0 mL) blend. In contrast, the addition of casein to the gluten-water blend negatively impacted firmness after heating. Firmness was correlated with loss of protein extractability in sodium dodecyl sulfate containing medium during heating, which was higher with egg white than with casein. Even more, heat-induced polymerization of the gluten-water blend with egg white but not with casein was greater than expected from the losses in extractability of gluten and egg white on their own. CONCLUSION: Structure formation was favored by mixing gluten with egg white but not with casein. These observations were linked to the intrinsic polymerization behavior of egg white and casein, but also to their interaction with gluten. Thus not all nutritionally suitable proteins can be used for enrichment of gluten-based protein-rich foods.


Asunto(s)
Caseínas/química , Proteínas en la Dieta/química , Proteínas del Huevo/química , Glútenes/química , Triticum/química , Aminoácidos/análisis , Aminoácidos/química , Animales , Bovinos , Fenómenos Químicos , Pollos , Calor , Carne , Valor Nutritivo , Polimerizacion , Sensación
20.
Compr Rev Food Sci Food Saf ; 15(4): 786-800, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33401841

RESUMEN

Proteins play a crucial role in determining texture and structure of many food products. Although some animal proteins (such as egg white) have excellent functional and organoleptic properties, unfortunately, they entail a higher production cost and environmental impact than plant proteins. It is rather unfortunate that plant protein functionality is often insufficient because of low solubility in aqueous media. Enzymatic hydrolysis strongly increases solubility of proteins and alters their functional properties. The latter is attributed to 3 major structural changes: a decrease in average molecular mass, a higher availability of hydrophobic regions, and the liberation of ionizable groups. We here review current knowledge on solubility, water- and fat-holding capacity, gelation, foaming, and emulsifying properties of plant protein hydrolysates and discuss how these properties are affected by controlled enzymatic hydrolysis. In many cases, research in this field has been limited to fairly simple set-ups where functionality has been assessed in model systems. To evolve toward a more widely applied industrial use of plant protein hydrolysates, a more thorough understanding of functional properties is required. The structure-function relationship of protein hydrolysates needs to be studied in depth. Finally, test model systems closer to real food processing conditions, and thus to real foods, would be helpful to evaluate whether plant protein hydrolysates could be a viable alternative for other functional protein sources.

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