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1.
MicroPubl Biol ; 20232023.
Artículo en Inglés | MEDLINE | ID: mdl-37143449

RESUMEN

The no gametophores 4 ( nog4-R ) mutant cannot make the transition from 2-dimensional (2D) to 3-dimensional (3D) growth in Physcomitrium patens and forms side branch initials that are largely fated to become sporophyte-like structures. We describe the three different developmental trajectories adopted by the nog4-R mutant, all of which result in indeterminate growth and defects in cell division plane orientation. A candidate gene approach confirmed that the causative mutation resided in the CURLY LEAF gene, and we highlight a previously uncharacterized role for CURLY LEAF in maintaining auxin homeostasis in P. patens .

2.
Front Toxicol ; 5: 1051483, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36742129

RESUMEN

Understanding the metabolic fate of a xenobiotic substance can help inform its potential health risks and allow for the identification of signature metabolites associated with exposure. The need to characterize metabolites of poorly studied or novel substances has shifted exposure studies towards non-targeted analysis (NTA), which often aims to profile many compounds within a sample using high-resolution liquid-chromatography mass-spectrometry (LCMS). Here we evaluate the suitability of suspect screening analysis (SSA) liquid-chromatography mass-spectrometry to inform xenobiotic chemical metabolism. Given a lack of knowledge of true metabolites for most chemicals, predictive tools were used to generate potential metabolites as suspect screening lists to guide the identification of selected xenobiotic substances and their associated metabolites. Thirty-three substances were selected to represent a diverse array of pharmaceutical, agrochemical, and industrial chemicals from Environmental Protection Agency's ToxCast chemical library. The compounds were incubated in a metabolically-active in vitro assay using primary hepatocytes and the resulting supernatant and lysate fractions were analyzed with high-resolution LCMS. Metabolites were simulated for each compound structure using software and then combined to serve as the suspect screening list. The exact masses of the predicted metabolites were then used to select LCMS features for fragmentation via tandem mass spectrometry (MS/MS). Of the starting chemicals, 12 were measured in at least one sample in either positive or negative ion mode and a subset of these were used to develop the analysis workflow. We implemented a screening level workflow for background subtraction and the incorporation of time-varying kinetics into the identification of likely metabolites. We used haloperidol as a case study to perform an in-depth analysis, which resulted in identifying five known metabolites and five molecular features that represent potential novel metabolites, two of which were assigned discrete structures based on in silico predictions. This workflow was applied to five additional test chemicals, and 15 molecular features were selected as either reported metabolites, predicted metabolites, or potential metabolites without a structural assignment. This study demonstrates that in some-but not all-cases, suspect screening analysis methods provide a means to rapidly identify and characterize metabolites of xenobiotic chemicals.

3.
Essays Biochem ; 66(6): 769-779, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36342774

RESUMEN

The colonization of land by plants, and the greening of the terrestrial biosphere, was one of the most important events in the history of life on Earth. The transition of plants from water to land was accompanied, and largely facilitated, by the acquisition of apical cells with three or more cutting faces (3D growth). This enabled plants to develop the morphological characteristics required to survive and reproduce effectively on land and to colonize progressively drier habitats. Most plants develop in such a way that makes genetic studies of 3D growth difficult as the onset of 3D growth is established early during embryo development. On the other hand, in the moss Physcomitrium patens, the onset of 3D growth is preceded by a protracted 2D filamentous phase of the life cycle that can be continuously propagated. P. patens is an ideal model system in which to identify the genetic toolkit underpinning the 2D to 3D growth transition, and this is because 3D growth is not a pre-requisite for survival. Thus, insights into the mechanisms underpinning the formation of apical cells and the subsequent establishment and maintenance of 3D growth have largely been gained through studies in P. patens. This review summarizes the most recently published articles that have provided new and important insights into the mechanisms underpinning 3D growth in P. patens.

4.
PLoS Comput Biol ; 18(5): e1010109, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35639779

RESUMEN

Heterogeneity of cancer means many tumorigenic genes are only aberrantly expressed in a subset of patients and thus follow a bimodal distribution, having two modes of expression within a single population. Traditional statistical techniques that compare sample means between cancer patients and healthy controls fail to detect bimodally expressed genes. We utilize a mixture modeling approach to identify bimodal microRNA (miRNA) across cancers, find consistent sources of heterogeneity, and identify potential oncogenic miRNA that may be used to guide personalized therapies. Pathway analysis was conducted using target genes of the bimodal miRNA to identify potential functional implications in cancer. In vivo overexpression experiments were conducted to elucidate the clinical importance of bimodal miRNA in chemotherapy treatments. In nine types of cancer, tumors consistently displayed greater bimodality than normal tissue. Specifically, in liver and lung cancers, high expression of miR-105 and miR-767 was indicative of poor prognosis. Functional pathway analysis identified target genes of miR-105 and miR-767 enriched in the phosphoinositide-3-kinase (PI3K) pathway, and analysis of over 200 cancer drugs in vitro showed that drugs targeting the same pathway had greater efficacy in cell lines with high miR-105 and miR-767 levels. Overexpression of the two miRNA facilitated response to PI3K inhibitor treatment. We demonstrate that while cancer is marked by considerable genetic heterogeneity, there is between-cancer concordance regarding the particular miRNA that are more variable. Bimodal miRNA are ideal biomarkers that can be used to stratify patients for prognosis and drug response in certain types of cancer.


Asunto(s)
MicroARNs , Neoplasias , Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Genoma , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3
5.
Evol Dev ; 23(3): 123-136, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33822471

RESUMEN

One of the most defining moments in history was the colonization of land by plants approximately 470 million years ago. The transition from water to land was accompanied by significant changes in the plant body plan, from those than resembled filamentous representatives of the charophytes, the sister group to land plants, to those that were morphologically complex and capable of colonizing harsher habitats. The moss Physcomitrium patens (also known as Physcomitrella patens) is an extant representative of the bryophytes, the earliest land plant lineage. The protonema of P. patens emerges from spores from a chloronemal initial cell, which can divide to self-renew to produce filaments of chloronemal cells. A chloronemal initial cell can differentiate into a caulonemal initial cell, which can divide and self-renew to produce filaments of caulonemal cells, which branch extensively and give rise to three-dimensional shoots. The process by which a chloronemal initial cell differentiates into a caulonemal initial cell is tightly regulated by auxin-induced remodeling of the actin cytoskeleton. Studies have revealed that the genetic mechanisms underpinning this transition also regulate tip growth and differentiation in diverse plant taxa. This review summarizes the known cellular and molecular mechanisms underpinning the chloronema to caulonema transition in P. patens.


Asunto(s)
Bryopsida , Animales , Bryopsida/genética , Células Germinativas , Proteínas de Plantas
6.
J Nutr Biochem ; 91: 108598, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33549890

RESUMEN

Chronic metabolic diseases are on the rise worldwide and their etiology is multifactorial. Among them, inflammatory components like Tumor Necrosis Factor (TNF), contribute to whole-body metabolic impairment. Caloric Restriction (CR) combats metabolic diseases, but how it reduces inflammation remains understudied. We aimed to evaluate the impact of chronic CR on muscle inflammation, in particular TNF. In our study, 4-week old male Sprague-Dawley rats were fed a high-fat diet (HF, 45% Kcal of fat from lard) ad libitum for 3 months. After estimation of their energy requirement (1 month), they were then divided into three groups: HF ad libitum (OL), weight maintenance with AIN93M (9.5% Kcal from fat; ML, 100% of energy requirement), and caloric restriction (CR, AIN93M with 75% of energy requirement). This dietary intervention continued for six months. At this point, rats were sacrificed and gastrocnemius muscle was collected. CR induced a profound shift in fat and lean mass, and decreased growth factor IGF-1. Muscle qPCR analysis showed a marked decrease in inflammation and TNF (premRNA, mRNA, and protein) by CR, accompanied by Tnf promoter DNA hypermethylation. CR increased expression of histone deacetylase Sirt6 and decreased methyltransferase Suv39h1, together with decreased Tnf promoter and coding region binding of NF- κB and C/EBP-ß. Following miRNA database mining, qPCR analysis revealed that CR downregulated the proinflammatory miR-19b and increased the anti-inflammatory miR-181a and its known targets. Chronic CR is able to regulate muscle-specific inflammation by targeting the NF-κB pathway as well as transcriptional and post-transcriptional regulation of Tnf gene.


Asunto(s)
Restricción Calórica , Dieta Alta en Grasa , Músculo Esquelético/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Metilación de ADN , Masculino , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/genética
7.
Curr Biol ; 31(3): 555-563.e4, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33242390

RESUMEN

The colonization of land by plants was one of the most transformative events in the history of life on Earth. The transition from water, which coincided with and was likely facilitated by the evolution of three-dimensional (3D) growth, enabled the generation of morphological diversity on land. In many plants, the transition from two-dimensional (2D) to 3D growth occurs during embryo development. However, in the early divergent moss Physcomitrella patens, 3D growth is preceded by an extended filamentous phase that can be maintained indefinitely. Here, we describe the identification of the cytokinin-responsive NO GAMETOPHORES 2 (PpNOG2) gene, which encodes a shikimate o-hydroxycinnamoyltransferase. In mutants lacking PpNOG2 function, transcript levels of CLAVATA and SCARECROW genes are significantly reduced, excessive gametophore initial cells are produced, and buds undergo premature developmental arrest. Mutants also exhibit misregulation of auxin-responsive genes. Our results suggest that PpNOG2 functions in the ascorbic acid pathway leading to cuticle formation and that NOG2-related genes were co-opted into the lignin biosynthesis pathway after the divergence of bryophytes and vascular plants. We present a revised model of 3D growth in which PpNOG2 comprises part of a feedback mechanism that is required for the modulation of gametophore initial cell frequency. We also propose that the 2D to 3D growth transition in P. patens is underpinned by complex auxin-cytokinin crosstalk that is regulated, at least in part, by changes in flavonoid metabolism.


Asunto(s)
Bryopsida , Bryopsida/genética , Citocininas , Células Germinativas , Ácidos Indolacéticos , Proteínas de Plantas/genética
8.
BMC Med Genomics ; 13(Suppl 10): 148, 2020 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-33087122

RESUMEN

BACKGROUND: Advancements in transcriptomic profiling have led to the emergence of new challenges regarding data integration and interpretability. Variability between measurement platforms makes it difficult to compare between cohorts, and large numbers of gene features have encouraged the use black box methods that are not easily translated into biologically and clinically meaningful findings. We propose that gene rankings and algorithms that rely on relative expression within gene pairs can address such obstacles. METHODS: We implemented an innovative process to evaluate the performance of five feature selection methods on simulated gene-pair data. Along with TSP, we consider other methods that retain more information in their score calculations, including the magnitude of gene expression change as well as within-class variation. Tree-based rule extraction was also applied to serum microRNA (miRNA) pairs in order to devise a noninvasive screening tool for pancreatic and ovarian cancer. RESULTS: Gene pair data were simulated using different types of signal and noise. Pairs were filtered using feature selection approaches, including top-scoring pairs (TSP), absolute differences between gene ranks, and Fisher scores. Methods that retain more information, such as the magnitude of expression change and within-class variance, yielded higher classification accuracy using a random forest model. We then demonstrate two powerful applications of gene pairs by first performing large-scale integration of 52 breast cancer datasets consisting of 10,350 patients. Not only did we confirm known oncogenes, but we also propose novel tumorigenic genes, such as BSDC1 and U2AF1, that could distinguish between tumor subtypes. Finally, circulating miRNA pairs were filtered and salient rules were extracted to build simplified tree ensemble learners (STELs) for four types of cancer. These accessible clinical frameworks detected pancreatic and ovarian cancer with 84.8 and 93.6% accuracy, respectively. CONCLUSION: Rank-based gene pair classification benefits from careful feature selection methods that preserve maximal information. Gene pairs enable dataset integration for greater statistical power and discovery of robust biomarkers as well as facilitate construction of user-friendly clinical screening tools.


Asunto(s)
Detección Precoz del Cáncer/métodos , Perfilación de la Expresión Génica/métodos , Neoplasias/diagnóstico , Algoritmos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Biología Computacional , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/genética , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/genética , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética
9.
Clin Epigenetics ; 12(1): 138, 2020 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-32917280

RESUMEN

BACKGROUND: Inflammation has been associated with higher rates of recurrence and mortality in head and neck cancer (HNC). While the biological mechanisms predisposing patients to heightened inflammatory states remain largely unknown, DNA methylation has been proposed to reflect systemic inflammation. In this analysis, we attempt to identify meaningful epigenetic patterns in HNC survivors by stratifying individuals based on DNA methylation profiles in leukocytes. RESULTS: We used hierarchical clustering to uncover three distinct methylation patterns among HNC survivors. Each group displayed a unique methylation signature in inflammatory pathways including cytokine and B-cell receptor signaling. Additionally, we examined physiological, clinical, and lifestyle parameters related to inflammation, such as circulating carotenoid and cytokine levels, cancer treatment type, and alcohol consumption. Specifically, we identified one group of survivors who had significant differential methylation of transcriptional and translational regulators as well as genes in the T-cell receptor signaling pathway, including hypermethylation of CD40 ligand (CD40LG) and Tec protein tyrosine kinase (TEC) and hypomethylation of CD8A. This group also displayed high circulating lycopene levels. We identified another group that had distinctive methylation in the toll-like receptor (TLR) signaling pathway, including hypomethylation of TLR5, a component of the inhibitor of nuclear factor-kappa B kinase complex (CHUK), and two mitogen-activated protein kinases (MAP3K8 and MAP2K3). This group also had hypermethylation of mitochondrial ribosomal genes along with higher rates of alcohol consumption. CONCLUSION: The correlation between lycopene, alcohol consumption, DNA methylation, and inflammation warrants further investigation and may have implications in future recommendations and interventions to impact health outcomes in HNC survivors.


Asunto(s)
Consumo de Bebidas Alcohólicas/genética , Epigénesis Genética/genética , Neoplasias de Cabeza y Cuello/genética , Inflamación/genética , Licopeno/sangre , Carotenoides/sangre , Estudios de Casos y Controles , Islas de CpG/genética , Citocinas/metabolismo , Metilación de ADN/genética , Epigenómica/métodos , Genes Reguladores/genética , Humanos , Regiones Promotoras Genéticas/genética , Sobrevivientes/estadística & datos numéricos
10.
J Plant Res ; 133(3): 283-290, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32095969

RESUMEN

One of the most transformative events in the history of life on earth was the transition of plants from water to land approximately 470 million years ago. Within the Charophyte green algae, the closest living relatives of land plants, body plans have evolved from those that comprise simple unicells to those that are morphologically complex, large and multicellular. The Charophytes developed these broad ranging body plans by exploiting a range of one-dimensional and two-dimensional growth strategies to produce filaments, mats and branches. When plants were confronted with harsh conditions on land, they were required to make significant changes to the way they shaped their body plans. One of the fundamental developmental transitions that occurred was the evolution of three-dimensional growth and the acquisition of apical cells with three or more cutting faces. Plants subsequently developed a range of morphological adaptations (e.g. vasculature, roots, flowers, seeds) that enabled them to colonise progressively drier environments. 3D apical growth also evolved convergently in the brown algae, completely independently of the green lineage. This review summarises the evolving developmental complexities observed in the early divergent Charophytes all the way through to the earliest conquerors of land, and investigates 3D apical growth in the brown algae.


Asunto(s)
Evolución Biológica , Chlorophyta/crecimiento & desarrollo , Embryophyta/crecimiento & desarrollo , Filogenia , Chlorophyta/clasificación , Embryophyta/clasificación , Flores , Phaeophyceae/clasificación , Phaeophyceae/crecimiento & desarrollo , Raíces de Plantas
11.
Nutrients ; 11(9)2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-31484384

RESUMEN

Obesity and metabolic disease present a danger to long-term health outcomes. It has been hypothesized that epigenetic marks established during early life might program individuals and have either beneficial or harmful consequences later in life. In the present study, we examined whether maternal diet alters DNA methylation and whether such modifications persist after an obesogenic postnatal dietary challenge. During gestation and lactation, male Sprague-Dawley rats were exposed to either a high-fat diet (HF; n = 10) or low-fat diet (LF; n = 10). After weaning, all animals were fed a HF diet for an additional nine weeks. There were no differences observed in food intake or body weight between groups. Hepatic DNA methylation was quantified using both methylated DNA immunoprecipitation sequencing (MeDIP-seq) and methylation-sensitive restriction enzyme sequencing (MRE-seq). Overall, 1419 differentially methylated regions (DMRs) were identified. DMRs tended to be located in CpG shores and were enriched for genes involved in metabolism and cancer. Gene expression was measured for 31 genes in these pathways. Map3k5 and Igf1r were confirmed to be differentially expressed. Finally, we attempted to quantify the functional relevance of intergenic DMRs. Using chromatin contact data, we saw that conserved DMRs were topologically associated with metabolism genes, which were associated with differential expression of Adh5, Enox1, and Pik3c3. We show that although maternal dietary fat is unable to reverse offspring weight gain in response to a postnatal obesogenic diet, early life diet does program the hepatic methylome. Epigenetic alterations occur primarily in metabolic and cancer pathways and are associated with altered gene expression, but it is unclear whether they bear consequence later in life.


Asunto(s)
Dieta con Restricción de Grasas , Grasas de la Dieta/administración & dosificación , Epigenoma , Hígado/metabolismo , Fenómenos Fisiologicos Nutricionales Maternos , Obesidad/etiología , Animales , Islas de CpG , Metilación de ADN , Dieta Alta en Grasa , Epigénesis Genética , Femenino , Regulación de la Expresión Génica , Ratas , Ratas Sprague-Dawley
12.
Cancers (Basel) ; 11(8)2019 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-31382594

RESUMEN

Background: MicroRNAs have altered expression levels in various diseases and may play an important role in the diagnosis and prognosis of colorectal cancer (CRC). Methods: We systemically reviewed and quantitatively synthesized the scientific evidence pertaining to microRNA-20a (miR-20a) as a CRC biomarker. A keyword and reference search in PubMed yielded 32 studies, in which miR-20a was measured in feces, serum, or tumor tissue. Data were extracted from a total of 5014 cancer cases and 2863 controls. Results: Twenty out of 21 relevant studies found that miR-20a was upregulated in CRC patients compared to controls. Meta-analysis revealed a pooled miR-20a fold change of 2.45 (95% CI: 2.24-2.66) in CRC patients versus controls. To estimate sensitivity and specificity of miR-20a as a diagnostic biomarker of CRC, a pooled area under the receiver operating characteristic curve (AUROC) was calculated (0.70, 95% CI: 0.63-0.78). The prognostic capacity of miR-20a was assessed using hazard ratios (HRs) for the overall survival (OS). The meta-analysis estimated the pooled HR for OS to be 2.02 (95% CI: 0.90-3.14) in CRC patients with high miR-20a expression. Conclusions: miR-20a may be a valid biomarker for CRC detection but may not be a strong predictor of poor prognosis in CRC.

13.
Int J Mol Sci ; 20(13)2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31262088

RESUMEN

Calorie-dense high-fat diets (HF) are associated with detrimental health outcomes, including obesity, cardiovascular disease, and diabetes. Both pre- and post-natal HF diets have been hypothesized to negatively impact long-term metabolic health via epigenetic mechanisms. To understand how the timing of HF diet intake impacts DNA methylation and metabolism, male Sprague-Dawley rats were exposed to either maternal HF (MHF) or post-weaning HF diet (PHF). At post-natal week 12, PHF rats had similar body weights but greater hepatic lipid accumulation compared to the MHF rats. Genome-wide DNA methylation was evaluated, and analysis revealed 1744 differentially methylation regions (DMRs) between the groups with the majority of the DMR located outside of gene-coding regions. Within differentially methylated genes (DMGs), intragenic DNA methylation closer to the transcription start site was associated with lower gene expression, whereas DNA methylation further downstream was positively correlated with gene expression. The insulin and phosphatidylinositol (PI) signaling pathways were enriched with 25 DMRs that were associated with 20 DMGs, including PI3 kinase (Pi3k), pyruvate kinase (Pklr), and phosphodiesterase 3 (Pde3). Together, these results suggest that the timing of HF diet intake determines DNA methylation and gene expression patterns in hepatic metabolic pathways that target specific genomic contexts.


Asunto(s)
Metilación de ADN , Dieta Alta en Grasa/efectos adversos , Epigénesis Genética , Hígado/metabolismo , Efectos Tardíos de la Exposición Prenatal/genética , Animales , Femenino , Genotipo , Insulina/metabolismo , Metabolismo de los Lípidos , Masculino , Fosfatidilinositoles/metabolismo , Embarazo , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Sitio de Iniciación de la Transcripción
14.
Environ Epigenet ; 5(2): dvz009, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31240115

RESUMEN

Perinatal exposure to endocrine disrupting chemicals negatively impacts health, but the mechanism by which such toxicants damage long-term reproductive and metabolic function is unknown. Lipid metabolism plays a pivotal role in steroid hormone synthesis as well as energy utilization and storage; thus, aberrant lipid regulation may contribute to phthalate-driven health impairments. In order to test this hypothesis, we specifically examined epigenetic disruptions in lipid metabolism pathways after perinatal phthalate exposure. During gestation and lactation, pregnant Long-Evans rat dams were fed environmentally relevant doses of phthalate mixture: 0 (CON), 200 (LO), or 1000 (HI) µg/kg body weight/day. On PND90, male offspring in the LO and HI groups had higher body weights than CON rats. Gene expression of lipid metabolism pathways was altered in testis and adipose tissue of males exposed to the HI phthalate dosage. Specifically, Srebf1 was downregulated in testis and Srebf2 was upregulated in adipose tissue. In testis of HI rats, DNA methylation was increased at two loci and reduced at one other site surrounding Srebf1 transcription start site. In adipose tissue of HI rats, we observed increased DNA methylation at one region within the first intron of Srebf2. Computational analysis revealed several potential transcriptional regulator binding sites, suggesting functional relevance of the identified differentially methylated CpGs. Overall, we show that perinatal phthalate exposure affects lipid metabolism gene expression in a tissue-specific manner possibly through altering DNA methylation of Srebf1 and Srebf2.

15.
Adv Nutr ; 10(3): 520-536, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30915465

RESUMEN

Chronic caloric restriction (CR) without malnutrition is known to affect different cellular processes such as stem cell function, cell senescence, inflammation, and metabolism. Despite the differences in the implementation of CR, the reduction of calories produces a widespread beneficial effect in noncommunicable chronic diseases, which can be explained by improvements in immuno-metabolic adaptation. Cellular adaptation that occurs in response to dietary patterns can be explained by alterations in epigenetic mechanisms such as DNA methylation, histone modifications, and microRNA. In this review, we define these modifications and systematically summarize the current evidence related to CR and the epigenome. We then explain the significance of genome-wide epigenetic modifications in the context of disease development. Although substantial evidence exists for the widespread effect of CR on longevity, there is no consensus regarding the epigenetic regulations of the underlying cellular mechanisms that lead to improved health. We provide compelling evidence that CR produces long-lasting epigenetic effects that mediate expression of genes related to immuno-metabolic processes. Epigenetic reprogramming of the underlying chronic low-grade inflammation by CR can lead to immuno-metabolic adaptations that enhance quality of life, extend lifespan, and delay chronic disease onset.


Asunto(s)
Adaptación Fisiológica , Restricción Calórica , Enfermedad Crónica/terapia , Epigénesis Genética , Enfermedades no Transmisibles/terapia , Humanos , Inflamación
16.
J Nutr Biochem ; 65: 15-25, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30599393

RESUMEN

Environmental factors such as diet and endocrine-disrupting chemicals have individually been shown to mediate metabolic function. However, the underlying mechanism by which the combination disrupts adipocyte morphology and fat storage remains unknown. The current study evaluated early-life programming by diet and phthalate exposure. During gestation and lactation, pregnant Long-Evans hooded rat dams were fed either a control (C) or high-fat (HF) diet and were orally administered one of three phthalate dosages (0, 200 or 1000 µg/kg/day), yielding six groups of offspring: C-0, C-200, C-1000, HF-0, HF-200 and HF-1000. On postnatal day (PND) 90, gonadal fat pads were collected and analyzed for histology, gene expression and DNA methylation. Differences in body weight were observed only in males. Hematoxylin and eosin staining revealed larger adipocyte size in HF-0 vs. C-0 females. Exposure to 200 or 1000 µg/kg/day phthalates modulated diet-induced changes in adipose morphology. Compared to C-0 females, HF-0 females also had higher expression of the adipogenesis gene Wnt receptor, frizzled 1 (Fzd1) and the triglyceride cleaving enzyme lipoprotein lipase (Lpl). These increases in gene expression were accompanied by lower DNA methylation surrounding the transcription start sites of the two genes. Diet-driven effects were observed in unexposed females but not in phthalate-treated rats. Results suggest a sex-specific association between perinatal HF diet and body weight, adipocyte size and DNA methylation. Perinatal phthalate exposure appears to produce a phenotype that more closely resembles HF-fed animals.


Asunto(s)
Adipocitos/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Ácidos Ftálicos/toxicidad , Adipogénesis/efectos de los fármacos , Adipogénesis/genética , Animales , Animales Recién Nacidos , Composición Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Tamaño de la Célula/efectos de los fármacos , Femenino , Receptores Frizzled/genética , Regulación de la Expresión Génica/efectos de los fármacos , Lactancia , Lipoproteína Lipasa/genética , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas Long-Evans , Receptores de Neurotransmisores/genética , Factores Sexuales
17.
J Acad Nutr Diet ; 119(4): 659-671, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30661935

RESUMEN

BACKGROUND: Higher intakes of cruciferous vegetables (CVs) and green leafy vegetables (GLVs) in observational studies are associated with improvements in survival and cancer-related biomarkers in patients diagnosed with head and neck cancer (HNC). These results have yet to be corroborated in a randomized clinical trial (RCT). OBJECTIVE: Determine the feasibility of implementing a 12-week RCT to increase CV and GLV intake in posttreatment HNC survivors. DESIGN AND PARTICIPANTS: This was a two-arm RCT conducted among 24 posttreatment HNC survivors. Survivors were recruited from a southeastern, National Cancer Institute-designated Comprehensive Cancer Center between January 2015 and September 2016. INTERVENTION: There were two groups: (1) an experimental group (n=12) receiving weekly 15- to 30-minute telephone dietary counseling from a registered dietitian nutritionist stressing 2.5 cups per week CVs and 3.5 cups per week GLVs, and (2) an attention control group (n=12) receiving weekly 15- to 30-minute telephone dietary counseling from a registered dietitian nutritionist focusing on general healthy eating for cancer survivors. Participants completed a baseline survey, three 24-hour dietary recalls, phlebotomy, and anthropometric measures prior to randomization and at the end of the 12-week study period. The experimental group also completed weekly vegetable record recalls. MAIN OUTCOME MEASURES: Primary outcomes included feasibility, recruitment, retention, adherence, and safety. Secondary outcomes included inflammatory markers and carotenoids. STATISTICAL ANALYSES PERFORMED: Descriptive statistics were generated for demographic, epidemiological, and clinical variables as well as the primary feasibility outcomes. Between- and within-group comparisons of mean serum cytokine and carotenoid levels were performed using appropriate statistical tests depending on their respective distributions for the purpose of generating preliminary effect sizes. RESULTS: Overall, 350 incident HNC cases were screened for eligibility, and 98 were eligible for study participation. Reasons for ineligibility and exclusion included deceased (n=93); wrong or inactive telephone numbers, or unable to be reached, or lost to follow-up (n=93); not meeting inclusion criteria (n=39); and too ill to participate (n=27). Of the 98 eligible HNC cases, 24 agreed to participate, for an enrollment rate of 25%. The most common reason for nonparticipation was distance (n=48), as participants were asked to report for two on-site assignments. The retention rate was 96%. Mean intervention adherence rates for weekly goals were 67% CV, 74% GLV, and 71% overall. Completion rate of weekly counseling calls was 90%. The experimental group reported an overall mean increase of 5.5 cups GLV and 3.5 cups CV per week from baseline intake, respectively. No significant between- or within-arm differences were observed for inflammatory markers or carotenoids. CONCLUSION: A posttreatment intervention aimed at increasing CV and GLV intake in HNC survivors is feasible. A larger RCT is needed to assess the efficacy of this intervention on disease outcomes.


Asunto(s)
Supervivientes de Cáncer/psicología , Dieta/métodos , Neoplasias de Cabeza y Cuello/dietoterapia , Verduras , Adulto , Carotenoides/sangre , Consejo , Dieta/psicología , Estudios de Factibilidad , Femenino , Neoplasias de Cabeza y Cuello/sangre , Neoplasias de Cabeza y Cuello/psicología , Humanos , Mediadores de Inflamación/sangre , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Proyectos Piloto , Teléfono
18.
Biochim Biophys Acta Gene Regul Mech ; 1862(2): 141-152, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30605728

RESUMEN

Carnitine palmitoyltransferase 1 (Cpt1a) is a rate-limiting enzyme that mediates the transport of fatty acids into the mitochondria for subsequent beta-oxidation. The objective of this study was to uncover how diet mediates the transcriptional regulation of Cpt1a. Pregnant Sprague Dawley rats were exposed to either a high-fat (HF) or low-fat control diet during gestation and lactation. At weaning, male offspring received either a HF or control diet, creating 4 groups: lifelong control diet (C/C; n = 12), perinatal HF diet (HF/C; n = 9), post-weaning HF diet (C/HF; n = 10), and lifelong HF diet (HF/HF; n = 10). Only HF/HF animals had higher hepatic Cpt1a mRNA expression than C/C. Epigenetic analysis revealed reduced DNA methylation (DNAMe) and increased histone 3 lysine 4 dimethylation (H3K4Me2) upstream and within the promoter of Cpt1a in the HF/HF group. This was accompanied by increased peroxisome proliferator activated receptor alpha (PPARα) and CCAAT/enhancer binding protein beta (C/EBPß) binding directly downstream of the Cpt1a transcription start site within the first intron. Findings were confirmed in rat hepatoma H4IIEC3 cells treated with non-esterified fatty acid (NEFA). After 12 h of NEFA treatment, there was an enrichment of SWI/SNF related matrix associated actin dependent regulator of chromatin subfamily D member 1 (BAF60a or SMARCD1) in the first intron of Cpt1a. We conclude that dietary fat elevates hepatic Cpt1a expression via a highly coordinated transcriptional mechanism involving increased H3K4Me2, reduced DNAMe, and recruitment of C/EBPß, PPARα, PGC1α, and BAF60a to the gene.


Asunto(s)
Carnitina O-Palmitoiltransferasa/genética , Dieta Alta en Grasa , Epigénesis Genética , Transcripción Genética , Animales , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Carnitina O-Palmitoiltransferasa/metabolismo , Línea Celular Tumoral , Metilación de ADN , Femenino , Histonas/metabolismo , Masculino , PPAR alfa/metabolismo , Embarazo , Ratas , Ratas Sprague-Dawley
19.
J Biomed Inform ; 100S: 100001, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-34384574

RESUMEN

Standard methods for detecting cancer-associated genes rely on comparison of sample means between cancer patients and healthy controls. While such methods have successfully identified several oncogenes and tumor suppressor genes, they neglect to account for heterogeneity within the cancer population. Genetic mutations, translocations, and amplifications are often inconsistent across tumors, and instead they often affect smaller subsets of patients. This concept gives rise to the idea of bimodally expressed genes, or genes that display two modes of expression within one population. Analysis of bimodal gene expression has been explored via a variety of techniques including test statistics and clustering. In this review, we summarize the methodologies used to quantify bimodal gene expression and address the utility of these genes in patient stratification and specialized therapeutics in breast and lung cancer. Finally we discuss the limitations and future directions for bimodal genes in the era of high-throughput sequencing and personalized medicine.

20.
J Pharm Pract ; 32(2): 126-131, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29162021

RESUMEN

OBJECTIVE: To compare the time taken and steps completed by nurses in the process of insulin preparation and administration using the pen device compared to the vial and syringe method. METHODS: Observational and exploratory study utilizing a time-motion analysis of nurses' administration of insulin using the pen versus vial and syringe delivery methods. Nurses were observed, video-recorded, and timed during insulin preparation and administration using each delivery method. The steps performed by nurses were observed against recommended processes for preparing and administering insulin, and the percentage of nurses completing each step was noted. RESULTS: A total of 137 (94%) nurses participated. Nurses took less time preparing and administering insulin with the pen device compared with the vial and syringe method (79 ± 18 seconds vs 88 ± 20 seconds, respectively, P < .001). The overall average completion rate of steps with the pen device was 90% ± 7% compared to 88% ± 7% with the vial and syringe method. CONCLUSION: The time taken by nurses to prepare and administer insulin was lower with the pen device compared with vial and syringe. Furthermore, areas were identified for potential nursing education to enhance safe and appropriate use of insulin with both delivery methods.


Asunto(s)
Sistemas de Liberación de Medicamentos/enfermería , Insulina/administración & dosificación , Estudios de Tiempo y Movimiento , Sistemas de Liberación de Medicamentos/métodos , Humanos , Inyecciones Subcutáneas/enfermería , Pacientes Internos , Enfermeras y Enfermeros , Entrenamiento Simulado , Jeringas
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