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1.
Food Funct ; 14(23): 10506-10519, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37943075

RESUMO

Background: Polyphenols are a broad group of compounds with a complex metabolic fate. Flavanones and their metabolites provide cardiovascular protection and assistance in long-term body composition management. Objective: This study evaluates the nutrikinetics and the bioavailability of phenolic compounds after both acute and chronic supplementation with a flavanone-rich product, namely Sinetrol® Xpur, in healthy overweight and obese volunteers. Design: An open-label study including 20 volunteers was conducted for 16 weeks. Participants received Sinetrol® Xpur, either a low dose (900 mg per day) or a high dose (1800 mg per day), in capsules during breakfast and lunch. They were advised to follow an individualized isocaloric diet and avoid a list of polyphenol-rich foods 48 hours before and during the pharmacokinetic measurements. Results: Over 20 phase II and colonic metabolites were measured in the plasma. Two peaks were observed at 1 h and 7h-10 h after the first capsule ingestion. No significant differences in the AUC were observed in circulating metabolites between both doses. In urine excretion, 53 metabolites were monitored, including human phase II and colonic metabolites, at weeks 1 and 16. Cumulative urine excretion was higher after the high dose than after the low dose in both acute and chronic studies. Total urinary metabolites were significantly lower in week 16 compared to week 1. Conclusion: Although the urinary excreted metabolites reduced significantly over 16 weeks, the circulating metabolites did not decrease significantly. This study suggests that chronic intake might not offer the same bioavailability as in the acute study, and this effect does not seem to be dose-dependent. The clinical trial registry number is NCT03823196.


Assuntos
Flavanonas , Humanos , Suplementos Nutricionais , Fenóis/farmacocinética , Polifenóis
2.
Nutrients ; 14(22)2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36432599

RESUMO

Dietary (poly)phenol intake derived from the daily consumption of five portions of fruits and vegetables could protect against the development of non-communicable diseases. However, the general population does not meet the recommended intake. Supplementation with (poly)phenol-rich ingredients, within a varied and balanced diet, could help in filling this nutritional gap. This study aimed to validate the proof-of-concept of a (poly)phenolic supplementation developed to enhance the daily consumption of potentially bioactive compounds. Oxxynea® is a (poly)phenol-rich ingredient developed to provide the quantity and the variety corresponding to five-a-day fruit and vegetable consumption. In this double-blind, randomized cross-over study, 10 participants were supplemented with 450 mg of a (poly)phenol-based supplement or a placebo. Pharmacokinetics and urinary excretion profiles were measured for 24 and 48 h, respectively, using UPHLC-MS/MS analysis. The pharmacokinetic profile displayed a triphasic absorption, indicating peaks of circulating metabolites at 1.75 ± 0.25 h, 4.50 ± 0.34 h, 9.50 ± 0.33 h and an average Tmax (time of maximal plasma concentration) of 6.90 ± 0.96 h. Similarly, the urinary profile showed maximum metabolite excretion at 3-6 h, 6-10 h and 14-24 h after supplement consumption. Compared to individual metabolites belonging to different (poly)phenolic subfamilies, the total circulating and excreted metabolites showed a reduced coefficient of variation (CV 38%). The overall bioavailability estimated was 27.4 ± 3.4%. Oxxynea® supplementation may provide a sustained exposure to several (poly)phenolic metabolites and catabolites and reduces the inter-individual variation that could arise from supplementing only one class of (poly)phenol.


Assuntos
Frutas , Verduras , Humanos , Frutas/metabolismo , Verduras/metabolismo , Fenol , Polifenóis , Estudos Cross-Over , Espectrometria de Massas em Tandem , Fenóis , Suplementos Nutricionais
3.
Nutrients ; 13(2)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540841

RESUMO

Overweight and obesity adversely affect health-related quality of life (HRQOL) through day-to-day impairments of both mental and physical functioning. It is assumed that polyphenols within the Mediterranean diet may contribute to improving HRQOL. This investigation aimed at studying the effects of a polyphenol-rich ingredient on HRQOL in overweight and obese but otherwise healthy individuals. A randomized, double-blind, placebo-controlled study including 72 volunteers was conducted. Subjects were randomly assigned to receive for a 16-week period either 900 mg/day of the supplement or a placebo. Dietary recommendations were individually determined and intakes were recorded. Daily physical mobility was also monitored. Improvement of HRQOL was set as the primary outcome and assessed at baseline and at the end of the investigation using the Short-Form 36 (SF-36) health survey. Body composition was analyzed using dual-energy X-ray absorptiometry (DXA). Physical activity was calculated using the International Physical Activity Questionnaire (IPAQ). After 16 weeks, despite there being no adherence to the Mediterranean Diet Serving Score (MDSS), supplemented individuals experienced significant HRQOL improvement (+5.3%; p = 0.001), including enhanced perceived physical (+11.2%; p = 0.002) and mental health (+4.1%; p = 0.021) components, with bodily pain, vitality, and general health being the greatest contributors. Body fat mass significantly decreased (-1.2 kg; p = 0.033), mainly within the trunk area (-1.0 kg; p = 0.002). Engagement in physical activity significantly increased (+1308 Met-min (Metabolic Equivalent Task minutes)/week; p = 0.050). Hence, chronic supplementation with nutritional diversity and dosing of a Mediterranean diet-inspired, polyphenol-rich ingredient resulted in significant amelioration in both perceived physical and mental health, concomitant with the improvement of body composition, in healthy subjects with excessive adiposity.


Assuntos
Obesidade/terapia , Sobrepeso/terapia , Extratos Vegetais/química , Polifenóis/administração & dosagem , Qualidade de Vida , Adulto , Composição Corporal/efeitos dos fármacos , Dieta Mediterrânea , Suplementos Nutricionais , Método Duplo-Cego , Exercício Físico , Feminino , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Placebos , Espanha , Resultado do Tratamento
4.
Artigo em Inglês | MEDLINE | ID: mdl-35010479

RESUMO

Free radicals are reactive products that have multiple effects on the human body. Endogenous and exogenous antioxidants manage the overproduction of free radicals. However, an imbalance between free radicals and antioxidant factors causes oxidative stress. Exercise and physical activity are factors that increase oxidative stress and disrupts the body's homeostasis. Intensity and duration of training, training characteristics, and fitness level can have positive or negative effects on oxidative stress. Green tea consumption is recommended for the prevention of a variety of diseases, health maintenance, and weight loss. The effectiveness of green tea is primarily due to the presence of catechins and polyphenols, specifically (-)-epigallocatechin-3-gallate, which has antioxidant and anti-inflammatory properties based on clinical and animal studies. This review investigates the effect of green tea exercise and their interactive effects on free radicals and sports improvement.


Assuntos
Desempenho Atlético , Chá , Animais , Antioxidantes/metabolismo , Exercício Físico , Humanos , Estresse Oxidativo , Espécies Reativas de Oxigênio
5.
Int J Sports Physiol Perform ; 15(3): 375-382, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31614330

RESUMO

PURPOSE: To compare the effects of 2 different intensity distribution training programs (threshold [THR] and polarized [POL]) on fat metabolism and neuromuscular variables. METHODS: Twenty ultrarunners were allocated to POL (n = 11; age 40.6 [9.7] y, weight 73.5 [10.8] kg, VO2max 55.8 [4.9] mL·kg-1·min-1) or THR group (n = 9; age 36.8 [9.2] y, weight 75.5 [10.4] kg, VO2max 57.1 [5.2] mL·kg-1·min-1) and performed a 12-week training program that consisted of 5 running sessions, 2 strength sessions, and 1 day of full rest per week. Both groups performed similar total training duration and load but with different intensity distribution during running sessions. Resting metabolic rate, fat metabolism, isometric rate of force development (RFD; N·s-1) and maximal voluntary contraction in the knee extensor, and electromyographic amplitude were measured before and after each program. RESULTS: A significant decrease in RFD0-100 ms (Δ -13.4%; P ≤ .001; effect size [ES] = 1.00), RFD0-200 ms (Δ -11.7%; P ≤ .001; ES = 1.4), and RFDpeak (Δ -18%; P ≤ .001; ES = 1.4) were observed in the POL group. In THR group, a significant increase in mean electromyographic amplitude (Δ 24.4%; P = .02; ES = 1.4) was observed. There were no significant differences between groups in any of the variables. CONCLUSIONS: Similar adaptations in fat metabolism and neuromuscular performance can be achieved after 12 weeks of POL or THR intensity distribution. However, THR distribution appears to better maintain strength (RFD) and improve mean electromyographic amplitude. Nevertheless, the combination of both running and maximum strength training could influence on results because of the residual fatigue thus inducing suboptimal adaptations in the POL group.

6.
Cell Rep ; 22(11): 2978-2994, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29539425

RESUMO

Abemaciclib, an inhibitor of cyclin dependent kinases 4 and 6 (CDK4/6), has recently been approved for the treatment of hormone receptor-positive breast cancer. In this study, we use murine syngeneic tumor models and in vitro assays to investigate the impact of abemaciclib on T cells, the tumor immune microenvironment and the ability to combine with anti-PD-L1 blockade. Abemaciclib monotherapy resulted in tumor growth delay that was associated with an increased T cell inflammatory signature in tumors. Combination with anti-PD-L1 therapy led to complete tumor regressions and immunological memory, accompanied by enhanced antigen presentation, a T cell inflamed phenotype, and enhanced cell cycle control. In vitro, treatment with abemaciclib resulted in increased activation of human T cells and upregulated expression of antigen presentation genes in MCF-7 breast cancer cells. These data collectively support the clinical investigation of the combination of abemaciclib with agents such as anti-PD-L1 that modulate T cell anti-tumor immunity.


Assuntos
Aminopiridinas/uso terapêutico , Benzimidazóis/uso terapêutico , Inibidor de Quinase Dependente de Ciclina p15/uso terapêutico , Inibidor de Quinase Dependente de Ciclina p18/uso terapêutico , Receptor de Morte Celular Programada 1/metabolismo , Aminopiridinas/farmacologia , Benzimidazóis/farmacologia , Inibidor de Quinase Dependente de Ciclina p15/farmacologia , Inibidor de Quinase Dependente de Ciclina p18/farmacologia , Humanos , Microambiente Tumoral
7.
Phytother Res ; 31(11): 1739-1746, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28856749

RESUMO

High-intensity exercises are known to provoke delayed onset muscle soreness (DOMS). Delayed onset muscle soreness typically occurs within the first 24 h, peaks between 24 and 72 h, and can last as long as 5-7 days post-exercise. Delayed onset muscle soreness is a multifactorial process involving both mechanical and biochemical components, associated with clinical features that may limit range of motion, and athletes seek for effective recovery strategies to optimize future training sessions. TensLess® is a food supplement developed to help manage post-exercise recovery. The supplement has been investigated on 13 recreationally active athletes of both sex, during a randomized, double-blind, and crossover clinical investigation, including a 3-week washout period. The clinical investigation was based on the study of TensLess® effects for DOMS management and on the reduction of associated muscle damages following an eccentric exercise protocol. Supplementation with TensLess® induced significant decrease in DOMS perception (-33%; p = 0.008) as of the first 24 h; this was significantly correlated with a lowered release of muscle damage-associated biomarkers, namely myoglobin, creatinine, and creatine kinase, for the whole length of the recovery period. Taken together, these positive results clearly indicate that post-exercise supplementation with TensLess® may preserve myocytes and reduce soreness following eccentric exercise-induced damages, and, accordingly, significantly shorten muscle recovery. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Suplementos Nutricionais , Exercício Físico , Músculo Esquelético/efeitos dos fármacos , Mialgia/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Polifenóis/uso terapêutico , Atletas , Creatina Quinase/sangue , Creatinina/sangue , Método Duplo-Cego , Humanos , Masculino , Mioglobina/sangue , Medição da Dor , Estudos Prospectivos , Adulto Jovem
8.
Nutrients ; 9(4)2017 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-28441760

RESUMO

Workout capacity is energy-production driven. To produce peak metabolic power outputs, the organism predominantly relies more on anaerobic metabolism, but this undoubtedly has a negative and limiting impact on muscle function and performance. The aim of the study was to evaluate if an innovative polyphenol-based food supplement, PerfLoad®, was able to improve metabolic homeostasis and physical performance during high-intensity exercises under anaerobic conditions. The effect of a supplementation has been investigated on fifteen recreationally-active male athletes during a randomized, double-blind and crossover clinical investigation. The Wingate test, an inducer of an unbalanced metabolism associated to oxidative stress, was used to assess maximum anaerobic power during a high-intensity exercise on a cycle ergometer. Supplementation with PerfLoad® correlated with a significant increase in total power output (5%), maximal peak power output (3.7%), and average power developed (5%), without inducing more fatigue or greater heart rate. Instead, oxidative homeostasis was stabilized in supplemented subjects. Such results demonstrated that PerfLoad® is a natural and efficient solution capable of, similarly to training benefits, helping athletes to improve their physical performance, while balancing their metabolism and reducing exercise-induced oxidative stress.


Assuntos
Suplementos Nutricionais , Exercício Físico , Polifenóis/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Eritropoese/efeitos dos fármacos , Humanos , Masculino , Polifenóis/administração & dosagem , Polifenóis/química , Adulto Jovem
9.
Int J Food Sci Nutr ; 68(7): 840-848, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28276901

RESUMO

Modern lifestyles face growing demands for natural solutions to help improve general well-being. Accordingly, mind-body activities such as yoga have considerably grown. However, beneficial effects require regular workout. Besides, literature suggests that polyphenols may demonstrate positive effects on both mental and physical health. Overweight and obese volunteers, for which well-being might be perceived degraded, were included in a 16-week double-blind, randomized and parallel trial with a daily supplementation of HolisFiit®, a polyphenol-rich food supplement. Body composition was assessed by dual-energy X-ray absorptiometry (DXA) technology; well-being was evaluated with both, Athens Insomnia Scale (AIS) and components from Short Form-36 questionnaire (SF-36). Body composition significantly rebalanced by 7.7% (p = .019) of the lean-to-fat mass ratio. Also, sleep quality significantly improved by 43% (p = .00015) as well as both physical and mental components from SF-36, respectively by 10% (p = .004) and 7% (p = .021). These data altogether, suggest that regular consumption of HolisFiit®, might significantly improve mind and body well-being.


Assuntos
Sobrepeso/tratamento farmacológico , Polifenóis/farmacologia , Adulto , Composição Corporal , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Qualidade de Vida , Redução de Peso
10.
PLoS One ; 8(12): e80638, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24324617

RESUMO

Mina is an epigenetic gene regulatory protein known to function in multiple physiological and pathological contexts, including pulmonary inflammation, cell proliferation, cancer and immunity. We showed previously that the level of Mina gene expression is subject to natural genetic variation linked to 21 SNPs occurring in the Mina 5' region. In order to explore the mechanisms regulating Mina gene expression, we set out to molecularly characterize the Mina promoter in the region encompassing these SNPs. We used three kinds of assays--reporter, gel shift and chromatin immunoprecipitation--to analyze a 2 kb genomic fragment spanning the upstream and intron 1 regions flanking exon 1. Here we discovered a pair of Mina promoters (P1 and P2) and a P1-specific enhancer element (E1). Pharmacologic inhibition and siRNA knockdown experiments suggested that Sp1/3 transcription factors trigger Mina expression through additive activity targeted to a cluster of four Sp1/3 binding sites forming the P1 promoter. These results set the stage for comprehensive analysis of Mina gene regulation from the context of tissue specificity, the impact of inherited genetic variation and the nature of upstream signaling pathways.


Assuntos
Elementos Facilitadores Genéticos , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp3/genética , Ativação Transcricional , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Epigênese Genética , Genes Reporter , Luciferases/genética , Luciferases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Polimorfismo de Nucleotídeo Único , Ligação Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Fator de Transcrição Sp1/antagonistas & inibidores , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp3/antagonistas & inibidores , Fator de Transcrição Sp3/metabolismo
11.
Nat Immunol ; 10(8): 872-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19561615

RESUMO

T helper type 2 (T(H)2) bias, which is the propensity of naive CD4(+) T cells to differentiate into interleukin 4 (IL-4)-secreting T(H)2 cells, is a genetic trait that affects susceptibility to infectious, autoimmune and allergic diseases. T(H)2 bias correlates with the amount of IL-4 initially secreted by newly activated helper T cells that feeds back positively through the pathway of the IL-4 receptor and the transcription factors STAT6 and GATA-3 to drive T(H)2 development. Here we identify Mina, a member of the jumonji C (JmjC) protein family, as a genetic determinant of T(H)2 bias. Mina specifically bound to and repressed the Il4 promoter. Mina overexpression in transgenic mice impaired Il4 expression, whereas its knockdown in primary CD4(+) T cells led to Il4 derepression. Our findings collectively provide mechanistic insight into an Il4-regulatory pathway that controls helper T cell differentiation and genetic variation in T(H)2 bias.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Interleucina-4/biossíntese , Proteínas de Neoplasias/fisiologia , Proteínas Nucleares/fisiologia , Células Th2/imunologia , Animais , Sequência de Bases , Linfócitos T CD4-Positivos/citologia , Diferenciação Celular , Fator de Transcrição GATA3/metabolismo , Haplótipos , Interleucina-4/genética , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Fator de Transcrição STAT6/metabolismo , Especificidade da Espécie , Células Th2/citologia
12.
EMBO J ; 26(10): 2562-74, 2007 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-17464290

RESUMO

Reduced levels of the cyclin-dependent kinase inhibitor p27(Kip1) connote poor prognosis in cancer. In human Burkitt lymphoma and in precancerous B cells and lymphomas arising in Emu-Myc transgenic mice, p27(Kip1) expression is markedly reduced. We show that the transcription of the Cks1 component of the SCF(Skp2) complex that is necessary for p27(Kip1) ubiquitylation and degradation is induced by Myc. Further, Cks1 expression is elevated in precancerous Emu-Myc B cells, and high levels of Cks1 are also a hallmark of Emu-Myc lymphoma and of human Burkitt lymphoma. Finally, loss of Cks1 in Emu-Myc B cells elevates p27(Kip1) levels, reduces proliferation and markedly delays lymphoma development and dissemination of disease. Therefore, Myc suppresses p27(Kip1) expression, accelerates cell proliferation and promotes tumorigenesis at least in part through its ability to selectively induce Cks1.


Assuntos
Linfoma de Burkitt/etiologia , Proteína Quinase CDC2/genética , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/antagonistas & inibidores , Linfoma de Células B/fisiopatologia , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Células da Medula Óssea/citologia , Proteína Quinase CDC2/metabolismo , Cruzamentos Genéticos , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/fisiologia , Humanos , Linfoma de Células B/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Retroviridae/genética , Células Tumorais Cultivadas
13.
Blood ; 110(1): 313-22, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17363733

RESUMO

Novel therapeutic strategies are needed to address the emerging problem of imatinib resistance. The histone deacetylase (HDAC) inhibitor suberoylanilide hydroxamic acid (SAHA) is being evaluated for imatinib-resistant chronic myelogenous leukemia (CML) and has multiple cellular effects, including the induction of autophagy and apoptosis. Considering that autophagy may promote cancer cell survival, we hypothesized that disrupting autophagy would augment the anticancer activity of SAHA. Here we report that drugs that disrupt the autophagy pathway dramatically augment the antineoplastic effects of SAHA in CML cell lines and primary CML cells expressing wild-type and imatinib-resistant mutant forms of Bcr-Abl, including T315I. This regimen has selectivity for malignant cells and its efficacy was not diminished by impairing p53 function, another contributing factor in imatinib resistance. Disrupting autophagy by chloroquine treatment enhances SAHA-induced superoxide generation, triggers relocalization and marked increases in the lysosomal protease cathepsin D, and reduces the expression of the cathepsin-D substrate thioredoxin. Finally, knockdown of cathepsin D diminishes the potency of this combination, demonstrating its role as a mediator of this therapeutic response. Our data suggest that, when combined with HDAC inhibitors, agents that disrupt autophagy are a promising new strategy to treat imatinib-refractory patients who fail conventional therapy.


Assuntos
Autofagia/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Antineoplásicos/farmacologia , Catepsina D/fisiologia , Linhagem Celular Tumoral , Cloroquina/farmacologia , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Proteínas de Fusão bcr-abl/farmacologia , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Vorinostat
14.
J Appl Physiol (1985) ; 99(4): 1508-15, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15961612

RESUMO

Phospholemman (PLM) is a recently identified accessory protein of the Na(+)-K(+)-ATPase (NKA), with a high level of expression in skeletal muscle. The objectives of this study are to characterize the PLM in skeletal muscle and to test the hypothesis that, as an accessory protein of NKA, expression of PLM and its association with the alpha-subunits of NKA is regulated during aging and with exercise training. PLM was characterized in skeletal muscle of 6- and 16-mo-old sedentary middle-aged rats (Ms), and the effects of aging and exercise training were studied in Ms, 29-mo-old sedentary senescent, and 29-mo-old treadmill-exercised senescent rats. Expression of PLM was muscle-type dependent, and immunofluorescence study showed that PLM distributed predominantly on the sarcolemmal membrane of the muscle fibers. Anti-PLM antibody reduced activity of NKA, and thus PLM appears to be required for NKA to express its full activity in skeletal muscle. Expression of PLM was not altered with aging but increased after exercise training. Coimmunoprecipitation studies demonstrated that PLM associates with both the alpha(1)- and alpha(2)-subunit isoforms of NKA. Compared with Ms rats, levels of PLM-associated alpha(1)-subunit increased in 29-mo-old sedentary senescent rats, and treadmill exercise has a tendency to partially reverse it. There was no significant change in PLM-associated alpha(2)-subunit with age, and exercise training has a tendency to increase that level. It is concluded that, in skeletal muscle, PLM appears to be a protein integral to the NKA complex and that PLM has the potential to modulate NKA in an isoform-specific and muscle type-dependent manner in aging and after exercise training.


Assuntos
Envelhecimento/metabolismo , Proteínas de Membrana/metabolismo , Músculo Esquelético/metabolismo , Fosfoproteínas/metabolismo , Condicionamento Físico Animal/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Imunofluorescência , Masculino , Ratos , Ratos Endogâmicos F344
15.
EMBO J ; 23(15): 3020-30, 2004 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-15257288

RESUMO

Breakdown of triple-helical interstitial collagens is essential in embryonic development, organ morphogenesis and tissue remodelling and repair. Aberrant collagenolysis may result in diseases such as arthritis, cancer, atherosclerosis, aneurysm and fibrosis. In vertebrates, it is initiated by collagenases belonging to the matrix metalloproteinase (MMP) family. The three-dimensional structure of a prototypic collagenase, MMP-1, indicates that the substrate-binding site of the enzyme is too narrow to accommodate triple-helical collagen. Here we report that collagenases bind and locally unwind the triple-helical structure before hydrolyzing the peptide bonds. Mutation of the catalytically essential residue Glu200 of MMP-1 to Ala resulted in a catalytically inactive enzyme, but in its presence noncollagenolytic proteinases digested collagen into typical 3/4 and 1/4 fragments, indicating that the MMP-1(E200A) mutant unwinds the triple-helical collagen. The study also shows that MMP-1 preferentially interacts with the alpha2(I) chain of type I collagen and cleaves the three alpha chains in succession. Our results throw light on the basic mechanisms that control a wide range of biological and pathological processes associated with tissue remodelling.


Assuntos
Colágeno/química , Colágeno/metabolismo , Metaloproteinase 1 da Matriz/química , Metaloproteinase 1 da Matriz/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Domínio Catalítico , Ácido Glutâmico/genética , Ácido Glutâmico/metabolismo , Hidrólise , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 3 da Matriz/química , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Mutação/genética , Estrutura Terciária de Proteína , Temperatura
16.
J Appl Physiol (1985) ; 97(4): 1291-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15155712

RESUMO

Vasoactive intestinal peptide (VIP) is known to induce histamine release in human skin and to include a nitric oxide (NO)-dependent dilation in several other vascular beds. However, the relative contribution of histamine and NO to VIP-mediated vasodilation in human skin is unknown. Forty-three subjects volunteered to participate in two studies designed to examine the mechanism of VIP-mediated vasodilation in human skin. Study 1 examined the contribution of NO in the skin blood flow response to eight doses of VIP ranging from 25 to 800 pmol. In addition, study 1 examined a specific role for NO in VIP-mediated dilation. Study 2 examined the relative contribution of NO and histamine to VIP-mediated dilation via H1 and H2 histamine receptors. Infusions were administered to skin sites via intradermal microdialysis. Red blood cell flux was measured by using laser-Doppler flowmetry (LDF), and cutaneous vascular conductance (CVC; LDF/mean arterial pressure) was calculated and normalized to maximal vasodilation. VIP-mediated vasodilation includes a NO-dependent component at doses above 100 pmol, where NO synthase inhibition significantly attenuates CVC (P < 0.05). Inhibition of H1 receptors attenuates the rise in CVC to exogenous VIP (P < 0.05); however, combined H1-receptor inhibition and NO synthase inhibition further reduced VIP-mediated vasodilation compared with either H1 inhibition or NO synthase inhibition alone (P < 0.05). In contrast to H1-receptor inhibition, H2-receptor inhibition did not affect vasodilation to exogenous VIP. Thus, in human skin, VIP-mediated vasodilation includes a NO-dependent component that could not be explained by H1- and H2-receptor activation.


Assuntos
Óxido Nítrico/metabolismo , Receptores Histamínicos/metabolismo , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Pele/irrigação sanguínea , Pele/efeitos dos fármacos , Peptídeo Intestinal Vasoativo/administração & dosagem , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Administração Tópica , Adulto , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Microdiálise/métodos , Vasodilatadores/administração & dosagem
17.
Obstet Gynecol ; 102(5 Pt 2): 1152-5, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14607039

RESUMO

BACKGROUND: Hereditary nonpolyposis colon cancer is associated with a 40-60% lifetime risk of endometrial cancer. Prophylactic hysterectomy is a reasonable management strategy for women who have completed childbearing. We report a case of a woman with hereditary nonpolyposis colon cancer who was found to have an unexpected endometrial cancer at prophylactic hysterectomy. CASE: A woman with hereditary nonpolyposis colon cancer underwent a laparoscopically assisted vaginal hysterectomy and bilateral salpingo-oophorectomy for prophylaxis against endometrial cancer. No unusual intraoperative findings were noted. Pathologic examination revealed a mixed clear cell and endometrioid endometrial carcinoma invading into the myometrium and cervix. The patient underwent a subsequent staging laparotomy, in which no additional disease was found. CONCLUSION: Patients with known hereditary nonpolyposis colon cancer undergoing prophylactic hysterectomy are at risk for having occult endometrial cancer. Gynecologists should consider preoperative endometrial biopsy and intraoperative assessment of the endometrium in these high-risk women.


Assuntos
Carcinoma Endometrioide/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/prevenção & controle , Histerectomia Vaginal , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco
18.
Cancer Res ; 63(19): 6195-9, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14559803

RESUMO

Overexpression of cdc25B, an important cell cycle regulator, has been shown to result in mammary gland hyperplasia in transgenic mice and to increase steroid hormone responsiveness as a direct coactivator of the estrogen receptor (ER). We investigated the potential role of cdc25B in the pathogenesis of endometrial carcinomas in conjunction with ER-alpha. We examined the expression of cdc25B and phosphorylated ER-alpha in 4 archived human specimens of normal endometrium; 7 endometrial hyperplasia with or without atypia; 32 endometrioid endometrial carcinoma (EEC), including 20 low-grade (grade 1) and 12 high-grade (grade 2 or 3) tumors; and 18 endometrial cancers with aggressive histological subtypes (uterine papillary serous carcinoma and clear cell carcinoma, UPSC/CCC) by immunohistochemistry with monoclonal antibodies. Expression of cdc25B and phosphorylated ER-alpha was increased in endometrial hyperplasia and atypical hyperplasia compared with normal secretory endometrium. Ninety percent (18 of 20) of the low-grade EEC expressed cdc25B at a high level, whereas only 42% (5 of 12) of the high-grade EEC did so (chi(2) = 8.7; P < 0.01). Sixty-five percent (13 of 20) of the low-grade EEC expressed phosphorylated ER-alpha at high levels, but only 17% (2 of 12) of high-grade EEC did so (chi(2) = 7.0; P < 0.01). Coordinate high-level expression of phosphorylated ER-alpha and cdc25B occurred in 65% (13 of 20) of low-grade EEC but in only 17% (2 of 12) of the high-grade EEC (chi(2) = 7.0; P < 0.01). In the UPSC/CCC tumors, only 22% (4 of 18) of the tumors expressed phosphorylated ER-alpha at high-levels. However, 83% (15 of 18) of these carcinomas showed high expression of cdc25B (chi(2) = 13.5; P < 0.01). The majority of the UPSC/CCC (15 of 18) did not show coordinate high expression of phosphorylated ER-alpha and cdc25B. Our findings show that in endometrial hyperplasia and low-grade EEC, coordinate increase in cdc25B and phosphorylated ER-alpha occurs. However, in UPSC/CCC, cdc25B is highly expressed without coordinate increase in phosphorylated ER-alpha. Cdc25B may play important roles in the development and progression of EEC and UPSC/CCC by different mechanisms.


Assuntos
Carcinoma Endometrioide/metabolismo , Carcinoma Endometrioide/patologia , Proteínas de Ciclo Celular/biossíntese , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Receptores de Estrogênio/biossíntese , Fosfatases cdc25/biossíntese , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/patologia , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Cistadenocarcinoma Papilar/metabolismo , Cistadenocarcinoma Papilar/patologia , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Receptor alfa de Estrogênio , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Fosforilação , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/biossíntese , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patologia
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