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1.
Cancer ; 130(15): 2713-2722, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38581694

RESUMO

BACKGROUND: The purpose of this randomised study was to determine whether dose-intensified stereotactic body radiotherapy (SBRT) for painful vertebral metastases results in increased rates of pain improvement compared with conventional external beam radiotherapy (cEBRT) (control) 6 months after treatment. METHODS: This randomized, controlled phase 3 trial was conducted between November 2016 and January 2023, when it was stopped early. Patients were eligible if they were aged 18 years or older; had one or two painful, stable, or potentially unstable vertebral metastases; and had a life expectancy of 1 year or longer according to the investigator's estimates. Patients received 48.5 grays (Gy) in 10 fractions (with epidural involvement) or 40 Gy in five fractions (without epidural involvement) in the SBRT group and 30 Gy in 10 fractions or 20 Gy in five fractions in the cEBRT group, respectively. The primary end point was an improvement in the pain score at the treated site by at least 2 points (on a visual analog scale from 0 to 10 points) at 6-month follow-up. Data were analyzed on an intention-to-treat and per-protocol basis. RESULTS: Of 214 patients who were screened for eligibility, 63 were randomized 1:1 between SBRT (33 patients with 36 metastases) and cEBRT (30 patients with 31 metastases). The median age of all patients was 66 years, and 40 patients were men (63.5%). In the intention-to-treat analysis, the 6-month proportion of patients who had metastases with pain reduction by 2 or more points was significantly higher in the SBRT group versus the control group (69.4% vs. 41.9%, respectively; two-sided p = .02). Changes in opioid medication intake relative to baseline were nonsignificant between the groups. No differences were observed in vertebral compression fracture or adverse event rates between the groups. CONCLUSIONS: Dose-intensified SBRT improved pain score more effectively than cEBRT at 6 months.


Assuntos
Radiocirurgia , Neoplasias da Coluna Vertebral , Humanos , Radiocirurgia/métodos , Masculino , Feminino , Idoso , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Pessoa de Meia-Idade , Medição da Dor , Dor do Câncer/radioterapia , Dor do Câncer/etiologia , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Resultado do Tratamento , Dosagem Radioterapêutica
2.
Obesity (Silver Spring) ; 31 Suppl 1: 9-21, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36349432

RESUMO

OBJECTIVE: The objective of this meta-analysis was to compare the effectiveness of different intermittent fasting (IF) regimens on weight loss, in the general population, and compare these to traditional caloric energy restriction (CER). METHODS: Three databases were searched from 2011 to June 2021 for randomized controlled trials (RCTs) that assessed weight loss and IF, including alternate day fasting (ADF), the 5:2 diet, and time-restricted eating (TRE). A random effect network analysis was used to compare the effectiveness between the three regimens. Meta-regression analysis was presented as weighted mean differences of body weight loss. RESULTS: The exploratory random effects network analysis of 24 RCTs (n = 1768) ranked ADF as the most effective, followed by CER and TRE. The meta-analysis showed that IF regimens resulted in similar weight loss to CER (mean difference 0.26 kg, 95% CI: -0.31 to 0.84; p = 0.37). Compliance was generally high (>80%) in trials shorter than 3 months. CONCLUSIONS: The present meta-analysis concludes that IF is comparable to CER and a promising alternative for weight loss. Among the three regimens, ADF showed the highest effectiveness for weight loss, followed by CER and TRE. Further well-powered RCTs with longer durations of intervention are required to draw solid conclusions.


Assuntos
Dieta Redutora , Obesidade , Humanos , Dieta Redutora/métodos , Jejum , Restrição Calórica/métodos , Redução de Peso
3.
Front Aging ; 3: 852569, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35821844

RESUMO

Glycine and cysteine are non-essential amino acids that are required to generate glutathione, an intracellular tripeptide that neutralizes reactive oxygen species and prevents tissue damage. During aging glutathione demand is thought to increase, but whether additional dietary intake of glycine and cysteine contributes towards the generation of glutathione in healthy older adults is not well understood. We investigated supplementation with glycine and n-acetylcysteine (GlyNAC) at three different daily doses for 2 weeks (low dose: 2.4 g, medium dose: 4.8 g, or high dose: 7.2 g/day, 1:1 ratio) in a randomized, controlled clinical trial in 114 healthy volunteers. Despite representing a cohort of healthy older adults (age mean = 65 years), we found significantly higher baseline levels of markers of oxidative stress, including that of malondialdehyde (MDA, 0.158 vs. 0.136 µmol/L, p < 0.0001), total cysteine (Cysteine-T, 314.8 vs. 276 µM, p < 0.0001), oxidized glutathione (GSSG, 174.5 vs. 132.3 µmol/L, p < 0.0001), and a lower ratio of reduced to oxidized glutathione (GSH-F:GSSG) (11.78 vs. 15.26, p = 0.0018) compared to a young reference group (age mean = 31.7 years, n = 20). GlyNAC supplementation was safe and well tolerated by the subjects, but did not increase levels of GSH-F:GSSG (end of study, placebo = 12.49 vs. 7.2 g = 12.65, p-value = 0.739) or that of total glutathione (GSH-T) (end of study, placebo = 903.5 vs. 7.2 g = 959.6 mg/L, p-value = 0.278), the primary endpoint of the study. Post-hoc analyses revealed that a subset of subjects characterized by high oxidative stress (above the median for MDA) and low baseline GSH-T status (below the median), who received the medium and high doses of GlyNAC, presented increased glutathione generation (end of study, placebo = 819.7 vs. 4.8g/7.2 g = 905.4 mg/L, p-value = 0.016). In summary GlyNAC supplementation is safe, well tolerated, and may increase glutathione levels in older adults with high glutathione demand. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT05041179, NCT05041179.

4.
Eur Urol ; 80(3): 306-315, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34140144

RESUMO

BACKGROUND: Salvage radiotherapy (SRT) is utilized for biochemical progression of prostate cancer after radical prostatectomy (RP). OBJECTIVE: To report the outcomes of the SAKK 09/10 trial comparing conventional and dose-intensified SRT. DESIGN, SETTING, AND PARTICIPANTS: SAKK 09/10 was a randomized, multicenter, phase 3 trial that recruited men with biochemical progression after RP. INTERVENTION: Patients were randomly assigned to conventional-dose (64 Gy) or dose-intensified SRT (70 Gy) to the prostate bed without hormonal therapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was freedom from biochemical progression (FFBP). Secondary endpoints included clinical progression-free survival (PFS), time to hormonal treatment, overall survival (OS), acute and late toxicity (Common Terminology Criteria for Adverse Events v4.0), and quality of life (QoL). RESULTS AND LIMITATIONS: Between February 2011 and April 2014, 350 patients were randomly assigned to 64 Gy (n = 175) or 70 Gy (n = 175). Median prostate-specific antigen at randomization was 0.3 ng/ml. After median follow-up of 6.2 yr, the median FFBP was 8.2 yr in the 64 Gy arm and 7.6 in the 70 Gy arm (log-rank p = 0.4), with a hazard ratio of 1.14 (95% confidence interval 0.82-1.60). The 6-year FFBP rates were 62% and 61%, respectively. No significant differences in clinical PFS, time to hormonal treatment, or OS were observed. Late grade 2 and 3 genitourinary toxicity was observed in 35 (21%) and 13 (7.9%) patients in the 64 Gy arm, and 46 (26%) and seven (4%) in the 70 Gy arm, respectively (p = 0.8). Late grade 2 and 3 gastrointestinal toxicity was observed in 12 (7.3%) and seven patients (4.2%) in the 64 Gy arm, and 35 (20%) and four (2.3%) in the 70 Gy arm, respectively (p = 0.009). There were no significant differences in QoL. CONCLUSIONS: Conventional-dose SRT to the prostate bed is sufficient in patients with early biochemical progression of prostate cancer after RP. PATIENT SUMMARY: The optimal radiation therapy dose for patients who have increased tumor markers after surgery for prostate cancer is unclear. We found that administering a higher dose only increased the gastrointestinal side effects without providing any benefits to the patient. This clinical trial is registered on ClinicalTrials.gov as NCT01272050.


Assuntos
Recidiva Local de Neoplasia , Neoplasias da Próstata , Idoso , Progressão da Doença , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/radioterapia , Antígeno Prostático Específico/sangue , Prostatectomia/efeitos adversos , Neoplasias da Próstata/sangue , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Qualidade de Vida , Dosagem Radioterapêutica , Terapia de Salvação/métodos
5.
Nat Commun ; 11(1): 5927, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33230181

RESUMO

Mitochondrial acyl-coenzyme A species are emerging as important sources of protein modification and damage. Succinyl-CoA ligase (SCL) deficiency causes a mitochondrial encephalomyopathy of unknown pathomechanism. Here, we show that succinyl-CoA accumulates in cells derived from patients with recessive mutations in the tricarboxylic acid cycle (TCA) gene succinyl-CoA ligase subunit-ß (SUCLA2), causing global protein hyper-succinylation. Using mass spectrometry, we quantify nearly 1,000 protein succinylation sites on 366 proteins from patient-derived fibroblasts and myotubes. Interestingly, hyper-succinylated proteins are distributed across cellular compartments, and many are known targets of the (NAD+)-dependent desuccinylase SIRT5. To test the contribution of hyper-succinylation to disease progression, we develop a zebrafish model of the SCL deficiency and find that SIRT5 gain-of-function reduces global protein succinylation and improves survival. Thus, increased succinyl-CoA levels contribute to the pathology of SCL deficiency through post-translational modifications.


Assuntos
Acil Coenzima A/metabolismo , Doenças Mitocondriais/patologia , Succinato-CoA Ligases/genética , Animais , Células Cultivadas , Feminino , Humanos , Lactente , Lisina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Mutação , Proteômica , Sirtuínas/deficiência , Sirtuínas/genética , Sirtuínas/metabolismo , Succinato-CoA Ligases/deficiência , Succinato-CoA Ligases/metabolismo , Análise de Sobrevida , Peixe-Zebra
6.
Elife ; 92020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32969791

RESUMO

The glucose-sensing Mondo pathway regulates expression of metabolic genes in mammals. Here, we characterized its function in the zebrafish and revealed an unexpected role of this pathway in vertebrate embryonic development. We showed that knockdown of mondoa impaired the early morphogenetic movement of epiboly in zebrafish embryos and caused microtubule defects. Expression of genes in the terpenoid backbone and sterol biosynthesis pathways upstream of pregnenolone synthesis was coordinately downregulated in these embryos, including the most downregulated gene nsdhl. Loss of Nsdhl function likewise impaired epiboly, similar to MondoA loss of function. Both epiboly and microtubule defects were partially restored by pregnenolone treatment. Maternal-zygotic mutants of mondoa showed perturbed epiboly with low penetrance and compensatory changes in the expression of terpenoid/sterol/steroid metabolism genes. Collectively, our results show a novel role for MondoA in the regulation of early vertebrate development, connecting glucose, cholesterol and steroid hormone metabolism with early embryonic cell movements.


In most animals, a protein called MondoA closely monitors the amount of glucose in the body, as this type of sugar is the fuel required for many life processes. Glucose levels also act as a proxy for the availability of other important nutrients. Once MondoA has detected glucose molecules, it turns genetic programmes on and off depending on the needs of the cell. So far, these mechanisms have mainly been studied in adult cells. However, recent studies have shown that proteins that monitor nutrient availability, and their associated pathways, can control early development. MondoA had not been studied in this context before, so Weger et al. decided to investigate its role in embryonic development. The experiments used embryos from zebrafish, a small freshwater fish whose early development is easily monitored and manipulated in the laboratory. Inhibiting production of the MondoA protein in zebrafish embryos prevented them from maturing any further, stopping their development at an early key stage. This block was caused by defects in microtubules, the tubular molecules that act like a microscopic skeleton to provide structural support for cells and guide transport of cell components. In addition, the pathway involved in the production of cholesterol and cholesterol-based hormones was far less active in embryos lacking MondoA. Treating MondoA-deficient embryos with one of these hormones corrected the microtubule defects and let the embryos progress to more advanced stages of development. These results reveal that, during development, the glucose sensor MondoA also controls pathways involved in the creation of cholesterol and associated hormones. These new insights into the metabolic regulation of development could help to understand certain human conditions; for example, certain patients with defective cholesterol pathway genes also show developmental perturbations. In addition, the work highlights a biological link between cholesterol production and cellular responses to glucose, which Weger et al. hope could one day help to identify new cholesterol-lowering drugs.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Colesterol/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Proteínas de Peixe-Zebra , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Colesterol/genética , Embrião não Mamífero , Gastrulação/genética , Técnicas de Silenciamento de Genes , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
7.
Mech Ageing Dev ; 191: 111316, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32693105

RESUMO

At a recent symposium on aging biology, a debate was held as to whether or not we know what biological aging is. Most of the participants were struck not only by the lack of consensus on this core question, but also on many basic tenets of the field. Accordingly, we undertook a systematic survey of our 71 participants on key questions that were raised during the debate and symposium, eliciting 37 responses. The results confirmed the impression from the symposium: there is marked disagreement on the most fundamental questions in the field, and little consensus on anything other than the heterogeneous nature of aging processes. Areas of major disagreement included what participants viewed as the essence of aging, when it begins, whether aging is programmed or not, whether we currently have a good understanding of aging mechanisms, whether aging is or will be quantifiable, whether aging will be treatable, and whether many non-aging species exist. These disagreements lay bare the urgent need for a more unified and cross-disciplinary paradigm in the biology of aging that will clarify both areas of agreement and disagreement, allowing research to proceed more efficiently. We suggest directions to encourage the emergence of such a paradigm.


Assuntos
Envelhecimento , Pesquisa Biomédica , Consenso , Humanos
8.
Front Cell Dev Biol ; 7: 282, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824944

RESUMO

Organogenesis is well characterized in vertebrates. However, the anatomical and functional development of intracellular compartments during this phase of development remains unknown. Taking an organellogenesis point of view, we characterize the spatiotemporal adaptations of the mitochondrial network during zebrafish embryogenesis. Using state of the art microscopy approaches, we find that mitochondrial network follows three distinct distribution patterns during embryonic development. Despite of this constant morphological change of the mitochondrial network, electron transport chain supercomplexes occur at early stages of embryonic development and conserve a stable organization throughout development. The remodeling of the mitochondrial network and the conservation of its structural components go hand-in-hand with somite maturation; for example, genetic disruption of myoblast fusion impairs mitochondrial network maturation. Reciprocally, mitochondria quality represents a key factor to determine embryonic progression. Alteration of mitochondrial polarization and electron transport chain halts embryonic development in a reversible manner suggesting developmental checkpoints that depend on mitochondrial integrity. Our findings establish the subtle dialogue and co-dependence between organogenesis and mitochondria in early vertebrate development. They also suggest the importance of adopting subcellular perspectives to understand organelle-organ communications during embryogenesis.

9.
FASEB J ; 33(11): 12374-12391, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31404503

RESUMO

AMPK is a central regulator of energy homeostasis. AMPK not only elicits acute metabolic responses but also promotes metabolic reprogramming and adaptations in the long-term through regulation of specific transcription factors and coactivators. We performed a whole-genome transcriptome profiling in wild-type (WT) and AMPK-deficient mouse embryonic fibroblasts (MEFs) and primary hepatocytes that had been treated with 2 distinct classes of small-molecule AMPK activators. We identified unique compound-dependent gene expression signatures and several AMPK-regulated genes, including folliculin (Flcn), which encodes the tumor suppressor FLCN. Bioinformatics analysis highlighted the lysosomal pathway and the associated transcription factor EB (TFEB) as a key transcriptional mediator responsible for AMPK responses. AMPK-induced Flcn expression was abolished in MEFs lacking TFEB and transcription factor E3, 2 transcription factors with partially redundant function; additionally, the promoter activity of Flcn was profoundly reduced when its putative TFEB-binding site was mutated. The AMPK-TFEB-FLCN axis is conserved across species; swimming exercise in WT zebrafish induced Flcn expression in muscle, which was significantly reduced in AMPK-deficient zebrafish. Mechanistically, we have found that AMPK promotes dephosphorylation and nuclear localization of TFEB independently of mammalian target of rapamycin activity. Collectively, we identified the novel AMPK-TFEB-FLCN axis, which may function as a key cascade for cellular and metabolic adaptations.-Collodet, C., Foretz, M., Deak, M., Bultot, L., Metairon, S., Viollet, B., Lefebvre, G., Raymond, F., Parisi, A., Civiletto, G., Gut, P., Descombes, P., Sakamoto, K. AMPK promotes induction of the tumor suppressor FLCN through activation of TFEB independently of mTOR.


Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Transporte Ativo do Núcleo Celular , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Células Cultivadas , Perfilação da Expressão Gênica , Hepatócitos/metabolismo , Camundongos , Fosforilação , Ribonucleotídeos/farmacologia , Peixe-Zebra
10.
Cell Metab ; 30(1): 190-200.e6, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31105043

RESUMO

Mitochondrial abundance and function are tightly controlled during metabolic adaptation but dysregulated in pathological states such as diabetes, neurodegeneration, cancer, and kidney disease. We show here that translation of PGC1α, a key governor of mitochondrial biogenesis and oxidative metabolism, is negatively regulated by an upstream open reading frame (uORF) in the 5' untranslated region of its gene (PPARGC1A). We find that uORF-mediated translational repression is a feature of PPARGC1A orthologs from human to fly. Strikingly, whereas multiple inhibitory uORFs are broadly present in fish PPARGC1A orthologs, they are completely absent in the Atlantic bluefin tuna, an animal with exceptionally high mitochondrial content. In mice, an engineered mutation disrupting the PPARGC1A uORF increases PGC1α protein levels and oxidative metabolism and confers protection from acute kidney injury. These studies identify a translational regulatory element governing oxidative metabolism and highlight its potential contribution to the evolution of organismal mitochondrial function.


Assuntos
Regiões 5' não Traduzidas/genética , Fases de Leitura Aberta/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Animais , Dípteros , Feminino , Células HEK293 , Humanos , Imunoprecipitação , Masculino , Camundongos , Mutação/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Filogenia , Processamento de Proteína Pós-Traducional/genética , Atum , Peixe-Zebra
11.
Front Cell Dev Biol ; 7: 15, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30873407

RESUMO

In the past years, evidence has emerged that hallmarks of human metabolic disorders can be recapitulated in zebrafish using genetic, pharmacological or dietary interventions. An advantage of modeling metabolic diseases in zebrafish compared to other "lower organisms" is the presence of a vertebrate body plan providing the possibility to study the tissue-intrinsic processes preceding the loss of metabolic homeostasis. While the small size of zebrafish is advantageous in many aspects, it also has shortcomings such as the difficulty to obtain sufficient amounts for biochemical analyses in response to metabolic challenges. A workshop at the European Zebrafish Principal Investigator meeting in Trento, Italy, was dedicated to discuss the advantages and disadvantages of zebrafish to study metabolic disorders. This perspective article by the participants highlights strategies to achieve improved tissue-resolution for read-outs using "nano-sampling" approaches for metabolomics as well as live imaging of zebrafish expressing fluorescent reporter tools that inform on cellular or subcellular metabolic processes. We provide several examples, including the use of reporter tools to study the heterogeneity of pancreatic beta-cells within their tissue environment. While limitations exist, we believe that with the advent of new technologies and more labs developing methods that can be applied to minimal amounts of tissue or single cells, zebrafish will further increase their utility to study energy metabolism.

12.
Sci Data ; 6: 190011, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30747917

RESUMO

Sequential window acquisition of all theoretical mass spectra (SWATH-MS) requires a spectral library to extract quantitative measurements from the mass spectrometry data acquired in data-independent acquisition mode (DIA). Large combined spectral libraries containing SWATH assays have been generated for humans and several other organisms, but so far no publicly available library exists for measuring the proteome of zebrafish, a rapidly emerging model system in biomedical research. Here, we present a large zebrafish SWATH spectral library to measure the abundance of 104,185 proteotypic peptides from 10,405 proteins. The library includes proteins expressed in 9 different zebrafish tissues (brain, eye, heart, intestine, liver, muscle, ovary, spleen, and testis) and provides an important new resource to quantify 40% of the protein-coding zebrafish genes. We employ this resource to quantify the proteome across brain, muscle, and liver and characterize divergent expression levels of paralogous proteins in different tissues. Data are available via ProteomeXchange (PXD010876, PXD010869) and SWATHAtlas (PASS01237).


Assuntos
Biblioteca de Peptídeos , Proteômica/métodos , Peixe-Zebra , Animais , Espectrometria de Massas , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
13.
Cell Signal ; 57: 45-57, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30772465

RESUMO

AMP-activated protein kinase (AMPK) is a key regulator of cellular energy homeostasis, acting as a sensor of energy and nutrient status. As such, AMPK is considered a promising drug target for treatment of medical conditions particularly associated with metabolic dysfunctions. To better understand the downstream effectors and physiological consequences of AMPK activation, we have employed a chemical genetic screen in mouse primary hepatocytes in an attempt to identify novel AMPK targets. Treatment of hepatocytes with a potent and specific AMPK activator 991 resulted in identification of 65 proteins phosphorylated upon AMPK activation, which are involved in a variety of cellular processes such as lipid/glycogen metabolism, vesicle trafficking, and cytoskeleton organisation. Further characterisation and validation using mass spectrometry followed by immunoblotting analysis with phosphorylation site-specific antibodies identified AMPK-dependent phosphorylation of Gapex-5 (also known as GTPase-activating protein and VPS9 domain-containing protein 1 (GAPVD1)) on Ser902 in hepatocytes and starch-binding domain 1 (STBD1) on Ser175 in multiple cells/tissues. As new promising roles of AMPK as a key metabolic regulator continue to emerge, the substrates we identified could provide new mechanistic and therapeutic insights into AMPK-activating drugs in the liver.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Musculares/metabolismo , Animais , Hepatócitos/metabolismo , Homeostase/genética , Homeostase/fisiologia , Metabolismo dos Lipídeos/genética , Espectrometria de Massas/métodos , Camundongos Knockout , Fosforilação , Especificidade por Substrato
14.
Science ; 361(6403)2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30026314

RESUMO

Wnt signaling is key to many developmental, physiological, and disease processes in which cells seem able to discriminate between multiple Wnt ligands. This selective Wnt recognition or "decoding" capacity has remained enigmatic because Wnt/Frizzled interactions are largely incompatible with monospecific recognition. Gpr124 and Reck enable brain endothelial cells to selectively respond to Wnt7. We show that Reck binds with low micromolar affinity to the intrinsically disordered linker region of Wnt7. Availability of Reck-bound Wnt7 for Frizzled signaling relies on the interaction between Gpr124 and Dishevelled. Through polymerization, Dishevelled recruits Gpr124 and the associated Reck-bound Wnt7 into dynamic Wnt/Frizzled/Lrp5/6 signalosomes, resulting in increased local concentrations of Wnt7 available for Frizzled signaling. This work provides mechanistic insights into the Wnt decoding capacities of vertebrate cells and unravels structural determinants of the functional diversification of Wnt family members.


Assuntos
Proteínas Desgrenhadas/metabolismo , Receptores Frizzled/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Animais , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Células Endoteliais/metabolismo , Células HEK293 , Humanos , Ligantes , Neovascularização Fisiológica , Ligação Proteica , Peixe-Zebra
15.
Radiother Oncol ; 126(2): 257-262, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29103826

RESUMO

INTRODUCTION: Adjuvant radiation therapy (aRT) after radical prostatectomy (RP) is associated with impaired urinary continence recovery as compared to surveillance. Less is known regarding the effect of salvage radiation therapy (sRT) dose intensification on continence outcomes. MATERIALS AND METHODS: Urinary continence recovery was investigated within a multicentre randomized trial in biochemically recurrent prostate cancer patients who received either 64 Gy (32 fractions) or 70 Gy (35 fractions) sRT. Incontinence was assessed using Common Toxicity Criteria for Adverse Events v4.0 at baseline, at the end of sRT and 3 months afterward. Quality of life (QoL) was assessed with the EORTC QoL questionnaires C30 and PR25 at baseline and 3 months after completion of sRT. A total of 344 patients were evaluable. RESULTS: At baseline 233 (68%) of patients were fully continent and 14% in both arms became incontinent three months after treatment. Of the remaining 111 (32%) patients being incontinent at baseline, continence recovery was achieved 3 months after sRT by 44% vs. 41% with 64 vs. 70 Gy, respectively (p = 0.8). This analysis is limited by its short follow-up. CONCLUSIONS: Dose intensification of sRT had no impact on early urinary continence recovery or prevalence of de novo incontinence.


Assuntos
Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Incontinência Urinária/etiologia , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/patologia , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Neoplasias da Próstata/patologia , Qualidade de Vida , Radioterapia Adjuvante/efeitos adversos , Terapia de Salvação/métodos , Incontinência Urinária/patologia
16.
Cell Metab ; 26(3): 547-557.e8, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28877458

RESUMO

Ketogenic diets recapitulate certain metabolic aspects of dietary restriction such as reliance on fatty acid metabolism and production of ketone bodies. We investigated whether an isoprotein ketogenic diet (KD) might, like dietary restriction, affect longevity and healthspan in C57BL/6 male mice. We find that Cyclic KD, KD alternated weekly with the Control diet to prevent obesity, reduces midlife mortality but does not affect maximum lifespan. A non-ketogenic high-fat diet (HF) fed similarly may have an intermediate effect on mortality. Cyclic KD improves memory performance in old age, while modestly improving composite healthspan measures. Gene expression analysis identifies downregulation of insulin, protein synthesis, and fatty acid synthesis pathways as mechanisms common to KD and HF. However, upregulation of PPARα target genes is unique to KD, consistent across tissues, and preserved in old age. In all, we show that a non-obesogenic ketogenic diet improves survival, memory, and healthspan in aging mice.


Assuntos
Envelhecimento/fisiologia , Dieta Cetogênica , Memória/fisiologia , Mortalidade , Animais , Dieta Hiperlipídica , Jejum , Regulação da Expressão Gênica , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , PPAR alfa/genética , PPAR alfa/metabolismo
17.
Physiol Rev ; 97(3): 889-938, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28468832

RESUMO

The burden of cardiovascular and metabolic diseases worldwide is staggering. The emergence of systems approaches in biology promises new therapies, faster and cheaper diagnostics, and personalized medicine. However, a profound understanding of pathogenic mechanisms at the cellular and molecular levels remains a fundamental requirement for discovery and therapeutics. Animal models of human disease are cornerstones of drug discovery as they allow identification of novel pharmacological targets by linking gene function with pathogenesis. The zebrafish model has been used for decades to study development and pathophysiology. More than ever, the specific strengths of the zebrafish model make it a prime partner in an age of discovery transformed by big-data approaches to genomics and disease. Zebrafish share a largely conserved physiology and anatomy with mammals. They allow a wide range of genetic manipulations, including the latest genome engineering approaches. They can be bred and studied with remarkable speed, enabling a range of large-scale phenotypic screens. Finally, zebrafish demonstrate an impressive regenerative capacity scientists hope to unlock in humans. Here, we provide a comprehensive guide on applications of zebrafish to investigate cardiovascular and metabolic diseases. We delineate advantages and limitations of zebrafish models of human disease and summarize their most significant contributions to understanding disease progression to date.


Assuntos
Doenças Cardiovasculares/genética , Descoberta de Drogas/métodos , Doenças Metabólicas/genética , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Fármacos Cardiovasculares/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Modelos Animais de Doenças , Predisposição Genética para Doença , Humanos , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/metabolismo , Doenças Metabólicas/fisiopatologia , Fenótipo , Especificidade da Espécie , Peixe-Zebra/metabolismo
18.
BJU Int ; 120(5B): E45-E51, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-27987524

RESUMO

OBJECTIVE: To conduct a central pathology review within a randomized clinical trial on salvage radiation therapy (RT) in the presence of biochemical recurrence after prostatectomy to assess whether this results in changes in histopathological prognostic factors, such as Gleason score. PATIENTS AND METHODS: A total of 350 patients were randomized and specimens from 279 patients (80%) were centrally reviewed by a dedicated genitourinary pathologist. Gleason score, tumour classification and resection margin status were reassessed and compared with the results of local pathology review. Agreement was assessed using contingency tables and Cohen's kappa coefficient. The association between other histopathological features (e.g. largest diameter of carcinoma) and rapid biochemical progression (up to 6 months after salvage RT) was also investigated. RESULTS: There was good concordance between central and local pathology review for seminal vesicle invasion (pT3b: 91%; κ = 0.95 [95% confidence interval {CI} 0.89, 1.00]), extraprostatic extension (pT3a/b: 94%; κ = 0.82 [95% CI 0.75, 0.89]) and positive surgical margin (PSM) status (87%; κ = 0.7 [95% CI 0.62, 0.79]). The rate of agreement was lower for Gleason score (78%; κ = 0.61 [95% CI 0.52, 0.70]). The median (range) largest diameter of carcinoma was 16 (3-38) mm. A total of 49 patients (18%) experienced rapid biochemical progression after salvage RT. Largest diameter of carcinoma (odds ratio [OR] 2.04 [95% CI 1.30, 3.20]; P = 0.002), resection margin status (OR 0.36 [95% CI 0.18, 0.72]; P = 0.004) and Gleason score (OR 1.55 [95% CI 1.00, 2.42]; P = 0.05) remained associated with rapid progression after salvage RT after backward selection. CONCLUSION: The results of the central pathology analyses showed concordance between central and local pathology review with regard to seminal vesicle invasion, extraprostatic extension and PSM status, but a lower rate of agreement for Gleason score. Largest diameter of carcinoma was found to be a potential prognostic factor for rapid biochemical progression after salvage RT.


Assuntos
Prostatectomia , Neoplasias da Próstata/patologia , Idoso , Ensaios Clínicos Fase III como Assunto , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Valor Preditivo dos Testes , Antígeno Prostático Específico , Radioterapia Adjuvante , Distribuição Aleatória , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Terapia de Salvação , Resultado do Tratamento
19.
J Clin Oncol ; 33(35): 4158-66, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26527774

RESUMO

PURPOSE: Patients with biochemical failure (BF) after radical prostatectomy may benefit from dose-intensified salvage radiation therapy (SRT) of the prostate bed. We performed a randomized phase III trial assessing dose intensification. PATIENTS AND METHODS: Patients with BF but without evidence of macroscopic disease were randomly assigned to either 64 or 70 Gy. Three-dimensional conformal radiation therapy or intensity-modulated radiation therapy/rotational techniques were used. The primary end point was freedom from BF. Secondary end points were acute toxicity according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.0) and quality of life (QoL) according to the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaires C30 and PR25. RESULTS: Three hundred fifty patients were enrolled between February 2011 and April 2014. Three patients withdrew informed consent, and three patients were not eligible, resulting in 344 patients age 48 to 75 years in the safety population. Thirty patients (8.7%) had grade 2 and two patients (0.6%) had grade 3 genitourinary (GU) baseline symptoms. Acute grade 2 and 3 GU toxicity was observed in 22 patients (13.0%) and one patient (0.6%), respectively, with 64 Gy and in 29 patients (16.6%) and three patients (1.7%), respectively, with 70 Gy (P = .2). Baseline grade 2 GI toxicity was observed in one patient (0.6%). Acute grade 2 and 3 GI toxicity was observed in 27 patients (16.0%) and one patient (0.6%), respectively, with 64 Gy, and in 27 patients (15.4%) and four patients (2.3%), respectively, with 70 Gy (P = .8). Changes in early QoL were minor. Patients receiving 70 Gy reported a more pronounced and clinically relevant worsening in urinary symptoms (mean difference in change score between arms, 3.6; P = .02). CONCLUSION: Dose-intensified SRT was associated with low rates of acute grade 2 and 3 GU and GI toxicity. The impact of dose-intensified SRT on QoL was minor, except for a significantly greater worsening in urinary symptoms.


Assuntos
Biomarcadores Tumorais/sangue , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/radioterapia , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/efeitos adversos , Terapia de Salvação/métodos , Transtornos Urinários/etiologia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/sangue , Neoplasias da Próstata/cirurgia , Qualidade de Vida , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Autorrelato , Índice de Gravidade de Doença , Micção/efeitos da radiação
20.
Biochem Soc Trans ; 43(4): 537-42, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26551690

RESUMO

The translocator protein (18 kDa) (TSPO) resides on the outer mitochondrial membrane where it is believed to participate in cholesterol transport and steroid hormone synthesis. Although it is almost ubiquitously expressed, what TSPO does in non-steroidogenic tissues is largely unexplored. Recent studies report changes in glucose homoeostasis and cellular energy production when TSPO function is modulated by selective ligands or by genetic loss-of-function. This review summarizes findings that connect TSPO function with the regulation of mitochondrial energy metabolism. The juxtaposition of TSPO at the cytosolic/mitochondrial interface and the existence of endogenous ligands that are regulated by metabolism suggest that TSPO functions to adapt mitochondrial to cellular metabolism. From a pharmacological perspective the specific up-regulation of TSPO in neuro-inflammatory and injury-induced conditions make TSPO an interesting, druggable target of mitochondrial metabolism.


Assuntos
Metabolismo Energético , Mitocôndrias/metabolismo , Receptores de GABA/metabolismo , Animais , Citosol/metabolismo , Metabolismo Energético/efeitos dos fármacos , Humanos , Ligantes , Membranas Mitocondriais/metabolismo , Regulação para Cima
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