RESUMO
Food-based diet indices provide a practical, rapid, and inexpensive way of evaluating dietary intake. Rather than nutrients, diet indices assess the intake of whole foods and dietary patterns, and compare these with nutrition guidelines. An athlete-specific diet index would offer an efficient and practical way to assess the quality of athletes' diets, guide nutrition interventions, and focus sport nutrition support. This study describes the development and validation of an Athlete Diet Index (ADI). Item development was informed by a review of existing diet indices, relevant literature, and in-depth focus groups with 20 sports nutritionists (median of 11 years' professional experience) from four elite athlete sporting institutes. Focus group data were analyzed (NVivo 11 Pro; QSR International Pty. Ltd., 2017, Melbourne, Australia), and key themes were identified to guide the development of athlete-relevant items. A modified Delphi survey in a subgroup of sports nutritionists (n = 9) supported item content validation. Pilot testing with athletes (n = 15) subsequently informed face validity. The final ADI (n = 68 items) was categorized into three sections. Section A (n = 45 items) evaluated usual intake, special diets or intolerances, dietary habits, and culinary skills. Section B (n = 15 items) assessed training load, nutrition supporting training, and sports supplement use. Section C (n = 8 items) captured the demographic details, sporting type, and caliber. All of the athletes reported the ADI as easy (40%) or very easy (60% of participants) to use and rated the tool as relevant (37%) or very relevant (63% of participants) to athletes. Further evaluation of the ADI, including the development of a scoring matrix and validation compared with established dietary methodology, is warranted.
Assuntos
Atletas , Dieta , Comportamento Alimentar , Avaliação Nutricional , Estado Nutricional , Inquéritos e Questionários/normas , Feminino , Humanos , Masculino , Fenômenos Fisiológicos da Nutrição EsportivaRESUMO
The aim of the present study was to investigate and benchmark the level of general nutrition knowledge in elite Australian athletes (EA) against a similar aged community (CM) and criterion sample with dietetic training (DT). EA (n 175), CM (n 116) and DT (n 53) completed the General Nutrition Knowledge Questionnaire (GNKQ), which assesses four domains (sections A-D) of general nutrition knowledge (section A: dietary guidelines; section B: sources of nutrients; section C: choosing everyday foods; section D: diet-disease relationships). Age, sex and education level were collected in all groups, and athletic calibre and sport type (team or individual) in EA. Dietitians and nutrition scientists (n 53) re-examined the GNKQ for content validity, resulting in instrument revision (R-GNKQ; ninety-six items). Psychometric assessment (internal consistency: Cronbach-α; test-retest: Spearman rank correlation) was performed in a sub-sample (n 28). Independent t tests, ANOVA and ANCOVA (χ² for categorical variables) were used to assess between-group differences. DT scored higher than EA and CM in all sub-sections and overall (P < 0·005). EA scored lower than CM in GNKQ for section B (P < 0·005) and overall (P < 0·005), and in R-GNKQ for section B (P < 0·005), section C (P < 0·005), section D (P = 0·006) and overall (P < 0·005). Overall score was influenced by age (P = 0·036 for GNKQ: P = 0·053 for R-GNKQ), sex (P = 0·016 for GNKQ: P = 0·003 for R-GNKQ) and athletic calibre (P = 0·029 for R-GNKQ only), but not level of education, living situation or ethnicity. EA and CM performed best on section A and worst on D. EA had lower overall general knowledge scores than CM. This was significantly influenced by age and sex.
Assuntos
Atletas , Dieta , Dietética , Comportamento Alimentar , Guias como Assunto , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Adulto , Fatores Etários , Análise de Variância , Austrália , Benchmarking , Feminino , Saúde , Humanos , Masculino , Psicometria , Fatores Sexuais , Adulto JovemRESUMO
Peripheral tolerance induction is critical for the maintenance of self-tolerance and can be mediated by immunoregulatory T cells or by direct induction of T-cell anergy or deletion. Although the molecular processes underlying anergy have been extensively studied, little is known about the molecular basis for peripheral T-cell deletion. Here, we determined the gene expression signature of peripheral CD8(+) T cells undergoing deletional tolerance, relative to those undergoing immunogenic priming or lymphopenia-induced proliferation. From these data, we report the first detailed molecular signature of cells undergoing deletion. Consistent with defective cytolysis, these cells exhibited deficiencies in granzyme up-regulation. Furthermore, they showed antigen-driven Bcl-2 down-regulation and early up-regulation of the proapoptotic protein Bim, consistent with the requirement of this BH3-only protein for peripheral T-cell deletion. Bim up-regulation was paralleled by defective interleukin-7 receptor alpha (IL-7Ralpha) chain reexpression, suggesting that Bim-dependent death may be triggered by loss of IL-7/IL-7R signaling. Finally, we observed parallels in molecular signatures between deletion and anergy, suggesting that these tolerance pathways may not be as molecularly distinct as previously surmised.
Assuntos
Apoptose/fisiologia , Biomarcadores/metabolismo , Linfócitos T CD8-Positivos/fisiologia , Transdução de Sinais , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Citometria de Fluxo , Perfilação da Expressão Gênica , Granzimas/metabolismo , Proteínas de Homeodomínio/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores de Interleucina-7/genética , Receptores de Interleucina-7/metabolismoRESUMO
A key learning outcome for undergraduate biochemistry classes is a thorough understanding of the principles of protein structure. Traditional approaches to teaching this material, which include two-dimensional (2D) images on paper, physical molecular modeling kits, and projections of 3D structures into 2D, are unable to fully capture the dynamic 3D nature of proteins. We have built a virtual reality application, Peppy, aimed at facilitating teaching of the principles of protein secondary structure. Rather than attempt to model molecules with the same fidelity to the underlying physical chemistry as existing, research-oriented molecular modelling approaches, we took the more straightforward approach of harnessing the Unity video game physics engine. Indeed, the simplicity and limitations of our model are strengths in a teaching context, provoking questions and thus deeper understanding. Peppy allows exploration of the relative effects of hydrogen bonding (and electrostatic interactions more generally), backbone φ/ψ angles, basic chemical structure, and steric effects on a polypeptide structure in an accessible format that is novel, dynamic, and fun to use. Apart from describing the implementation and use of Peppy, we discuss the outcomes of deploying Peppy in undergraduate biochemistry courses.
Assuntos
Bioquímica/educação , Peptídeos/química , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Secundária de Proteína , Interface Usuário-Computador , Jogos de Vídeo , Realidade VirtualRESUMO
The insulin-like growth factor (IGF) system is altered with intra-uterine growth retardation and in adult metabolic disease. The aim of the present study was to observe effects of continued protein restriction on the IGF-I system and body composition in offspring of mothers fed a low-protein (LP) diet. Offspring from Wistar dams fed either a 20 % (CON) or 8 % (LP) protein diet during gestation and lactation were studied at birth, 10 d, weaning and at 12 weeks after maintenance on either the 8 % (lp) or 20 % (con) protein diet from weaning. LP offspring had reduced weaning weights (P < 0.05) and reduced serum insulin (P < 0.005). Serum IGF-I (P < 0.001) and acid-labile subunit (ALS) (P < 0.0001) were reduced at 10 and 21 d. Hepatic expression of IGF-I (P < 0.05) and ALS (P < 0.005) were reduced at 10 and 21 d. IGF binding protein (IGFBP)-1 hepatic expression was elevated at 10 d (P < 0.001) but not at 21 d. Adult LP-con offspring had reduced body weight (P < 0.05), lean (P < 0.0001) and bone (P < 0.0001) but not fat (P = 0.6) mass with no persistent effects on IGF-I, ALS and IGFBP-1.Postnatal lp feeding reduced lean mass (P < 0.0001) and bone mass (P < 0.0001) in CON and LP animals. Percentage fat (LP P = 0.04; CON P = 0.6) and IGFBP-1 (LP P = 0.01; CON P = 0.2) were increased in LP-lp but not CON-lp offspring. This suggests that postnatal nutrition is important in the effects of maternal protein restriction on adult body composition and that IGFBP-1 may be involved.
Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Animais Recém-Nascidos/crescimento & desenvolvimento , Dieta com Restrição de Proteínas , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal , Ração Animal , Animais , Animais Recém-Nascidos/metabolismo , Composição Corporal , Peso Corporal , Proteínas de Transporte/sangue , Feminino , Glicoproteínas/sangue , Insulina/sangue , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Fator de Crescimento Insulin-Like I/análise , Lactação/fisiologia , Fígado/química , Gravidez , Ratos , Ratos Wistar , Fatores de Tempo , DesmameRESUMO
BACKGROUND: Many laboratories offer glycemic index (GI) services. OBJECTIVE: We assessed the performance of the method used to measure GI. DESIGN: The GI of cheese-puffs and fruit-leather (centrally provided) was measured in 28 laboratories (n=311 subjects) by using the FAO/WHO method. The laboratories reported the results of their calculations and sent the raw data for recalculation centrally. RESULTS: Values for the incremental area under the curve (AUC) reported by 54% of the laboratories differed from central calculations. Because of this and other differences in data analysis, 19% of reported food GI values differed by >5 units from those calculated centrally. GI values in individual subjects were unrelated to age, sex, ethnicity, body mass index, or AUC but were negatively related to within-individual variation (P=0.033) expressed as the CV of the AUC for repeated reference food tests (refCV). The between-laboratory GI values (mean+/-SD) for cheese-puffs and fruit-leather were 74.3+/-10.5 and 33.2+/-7.2, respectively. The mean laboratory GI was related to refCV (P=0.003) and the type of restrictions on alcohol consumption before the test (P=0.006, r2=0.509 for model). The within-laboratory SD of GI was related to refCV (P<0.001), the glucose analysis method (P=0.010), whether glucose measures were duplicated (P=0.008), and restrictions on dinner the night before (P=0.013, r2=0.810 for model). CONCLUSIONS: The between-laboratory SD of the GI values is approximately 9. Standardized data analysis and low within-subject variation (refCV<30%) are required for accuracy. The results suggest that common misconceptions exist about which factors do and do not need to be controlled to improve precision. Controlled studies and cost-benefit analyses are needed to optimize GI methodology. The trial was registered at clinicaltrials.gov as NCT00260858.
Assuntos
Técnicas de Laboratório Clínico/normas , Carboidratos da Dieta/metabolismo , Análise de Alimentos/normas , Alimentos/classificação , Índice Glicêmico , Adolescente , Adulto , Idoso , Área Sob a Curva , Glicemia/metabolismo , Estudos Cross-Over , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Nutrition literacy is linked to health via its influence on dietary intake. There is a need for a tool to assess nutrition literacy in research and dietetic practice. We sought guidance from nutrition professionals on topic areas and features of an electronic nutrition literacy assessment tool for Australian adults. 28 experienced nutrition professionals engaged in a range of nutrition and dietetic work areas participated in six focus groups using a semi-structured interview schedule. Data were analysed using an inductive approach using NVivo 10 (QSR International, Pty Ltd., Doncaster, Australia, 2012). Key areas identified to assess nutrition literacy included specific nutrients versus foods, labels and packaging, construction of the diet, knowledge of the Australian Dietary Guidelines and Australian Guide to Healthy Eating, understanding of serve and portion sizes, ability to select healthier foods, and demographics such as belief systems and culture. Exploitation of electronic features to enhance visual and auditory displays, including interactive animations such as "drag and drop" and virtual reality situations, were discussed. This study provided insight into the most relevant topic areas and presentation format to assess the nutrition literacy of adult Australians. The visual, auditory, and interactive capacity of the available technology could enhance the assessment of nutrition literacy.
Assuntos
Coleta de Dados , Dietética/educação , Conhecimentos, Atitudes e Prática em Saúde , Letramento em Saúde , Estado Nutricional , Adulto , Austrália , Comportamento de Escolha , Dieta Saudável , Estudos de Avaliação como Assunto , Grupos Focais , Embalagem de Alimentos , Preferências Alimentares , Humanos , Política Nutricional , Tamanho da Porção , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Shifts in the gastrointestinal microbiome have been shown to contribute to the progression of metabolic diseases including prediabetes and type 2 diabetes mellitus. Research suggests that in-vivo modulation of the gut microbiome by specific probiotic microorganisms may improve insulin sensitivity and blood sugar management, preventing or delaying the development of type 2 diabetes mellitus. However, further research is needed to understand the effect of probiotics as a therapy for the treatment of metabolic diseases. An evidence-based multi-species probiotic was developed to encourage a shift in the gastrointestinal bacterial cohort from a disease-prone to a balanced state with the aim of improving metabolic markers associated with type 2 diabetes mellitus. METHODS: Sixty adults with a body mass index ≥25 kg/m2 with prediabetes or type 2 diabetes mellitus (diagnosed within the previous 12 months) will be enrolled in a double-blind, placebo-controlled pilot study. Participants will be randomized to a multi-species probiotic or placebo for 12 weeks. Both groups will receive lifestyle and nutritional advice. The primary outcome measure is the change between groups in fasting plasma glucose levels from baseline to 12 weeks. Secondary outcome measures include, but are not limited to, the change in lipid profile, systemic inflammation, gut permeability, and faecal microbial and metabolomic profiles. Blood and stool samples are collected at baseline and 12 weeks after treatment. DISCUSSION: Intentional manipulation of gastrointestinal microbial profiles may be useful for preventing and controlling type 2 diabetes mellitus and its associated metabolic complications. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12613001378718 . Registered on 16 December 2013.
Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/terapia , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Estado Pré-Diabético/terapia , Probióticos/uso terapêutico , Biomarcadores/sangue , Protocolos Clínicos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/microbiologia , Método Duplo-Cego , Fezes/microbiologia , Humanos , Mediadores da Inflamação/sangue , Lipídeos/sangue , New South Wales , Projetos Piloto , Estado Pré-Diabético/sangue , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/microbiologia , Probióticos/efeitos adversos , Projetos de Pesquisa , Fatores de Tempo , Resultado do TratamentoRESUMO
Increased availability of fatty acids causes cell death and dysfunction in beta-cell lines, isolated islets, and animal models of diabetes. From the MIN6 beta-cell line, we selected two subpools that are resistant to palmitate-induced apoptosis. Protection was not universal because palmitate-resistant cells remained sensitive to cytokine- and streptozotocin-induced apoptosis. Palmitate oxidation and incorporation into cholesterol ester (but not triglycerides) were significantly higher in palmitate-resistant cells than in control cells. Consistent with these findings, transcript profiling revealed increased expression in palmitate-resistant cells of several beta-oxidation genes as well as a 2.8-fold upregulation of stearoyl-CoA desaturase 1 (SCD1). Correspondingly, the oleate-to-palmitate ratio of palmitate-resistant cells was double that of palmitate-pretreated control cells. At least some of this additional oleate in palmitate-resistant cells was incorporated into cholesterol ester stored in the form of large cytosolic lipid bodies. However, blocking cholesterol ester formation did not render palmitate-resistant cells sensitive to palmitate-induced apoptosis. On the other hand, an inhibitor of SCD1, 10,12-conjugated linoleic acid, dose dependently overcame the resistance of palmitate-resistant cells to lipoapoptosis. Our results suggest that desaturation per se is more important in protecting beta-cells from the cytotoxic effects of palmitate than is the nature of neutral lipid storage pool thus generated.
Assuntos
Apoptose , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos/metabolismo , Ilhotas Pancreáticas/patologia , Ácido Palmítico/toxicidade , Estearoil-CoA Dessaturase/metabolismo , Animais , Apoptose/efeitos dos fármacos , Ésteres do Colesterol/metabolismo , Resistência a Medicamentos , Ilhotas Pancreáticas/química , Lipídeos/análise , Camundongos , Oxirredução , Ácido Palmítico/metabolismo , Ácido Palmítico/farmacologia , Estearoil-CoA Dessaturase/antagonistas & inibidores , Triglicerídeos/metabolismoRESUMO
Insulin resistance is commonly observed in patients prior to the development of type 2 diabetes and may predict the onset of the disease. We tested the hypothesis that impairment in insulin stimulated glucose-disposal in insulin resistant patients would be reflected in the gene expression profile of skeletal muscle. We performed gene expression profiling on skeletal muscle of insulin resistant and insulin sensitive subjects using microarrays. Microarray analysis of 19,000 genes in skeletal muscle did not display a significant difference between insulin resistant and insulin sensitive muscle. This was confirmed with real-time PCR. Our results suggest that insulin resistance is not reflected by changes in the gene expression profile in skeletal muscle.
Assuntos
Expressão Gênica , Resistência à Insulina/genética , Músculo Quadríceps/fisiologia , Adulto , Biópsia , Estudos de Casos e Controles , Feminino , Perfilação da Expressão Gênica , Humanos , Insulina/metabolismo , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Músculo Quadríceps/patologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
A microarray experiment is presented that, in six laboratory sessions, takes undergraduate students from the tissue sample right through to data analysis. The model chosen, the murine erythroleukemia cell line, can be easily cultured in sufficient quantities for class use. Large changes in gene expression can be induced in these cells by erythropoietic agents such as DMSO over a 72-h time period. Students isolate total RNA from control (0 h) and 72-h DMSO-treated murine erythroleukemia cells. From this, they synthesize a cDNA copy incorporating amino-allyl dUTP, which is then coupled to either a Cy5 or a Cy3 dye. Equal amounts of the two labeled cDNA samples are then applied to a standard cDNA microarray, which is then hybridized, washed, and scanned. Up- and down-regulated genes are selected using an "in-house" user-friendly data base program. Quality control checks are included at various stages throughout the procedure and, as the process of erythropoiesis is well characterized, a number of erythroid sequences serve as internal controls on the validity of the array data. Through this experiment, students gain experience in a wide range of molecular biology techniques, the use of controls to check a multistep process, validation of results, and strategies to manage the large amount of data generated. Most importantly, it provides undergraduate students with an opportunity to carry out experiments using cutting edge techniques normally found only in research laboratories.
RESUMO
Chronic lipid exposure is implicated in beta-cell dysfunction in type 2 diabetes. We therefore used oligonucleotide arrays to define global alterations in gene expression in MIN6 cells after 48-h pretreatment with oleate or palmitate. Altogether, 126 genes were altered > or =1.9-fold by palmitate, 62 by oleate, and 46 by both lipids. Importantly, nine of the palmitate-regulated genes are known to be correspondingly changed in models of type 2 diabetes. A tendency toward beta-cell de-differentiation was also apparent with palmitate: pyruvate carboxylase and mitochondrial glycerol 3-phosphate dehydrogenase were downregulated, whereas lactate dehydrogenase and fructose 1,6-bisphosphatases were induced. Increases in the latter (also seen with oleate), along with glucosamine-phosphate N-acetyl transferase, imply upregulation of the hexosamine biosynthesis pathway in palmitate-treated cells. However, palmitate also increased expression of calcyclin and 25-kDa synaptosomal-associated protein (SNAP25), which control distal secretory processes. Consistent with these findings, secretory responses to noncarbohydrate stimuli, especially palmitate itself, were upregulated in palmitate-treated cells (much less so with oleate). Indeed, glucose-stimulated secretion was slightly sensitized by chronic palmitate exposure but inhibited by oleate treatment, whereas both lipids enhanced basal secretion. Oleate and palmitate also induced expression of chemokines (MCP-1 and GRO1 oncogene) and genes of the acute phase response (serum amyloid A3). Increases in transcriptional modulators such as ATF3, CCAAT/enhancer binding protein-beta (C/EBPbeta), C/EBPdelta, and c-fos were also seen. The results highlight links between regulated gene expression and phenotypic alterations in palmitate versus oleate-pretreated beta-cells.
Assuntos
Impressões Digitais de DNA , Enzimas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Ilhotas Pancreáticas/fisiologia , Ácido Oleico/farmacologia , Ácido Palmítico/farmacologia , Proteínas de Fase Aguda/genética , Animais , Linhagem Celular , Quimiocinas/genética , Genes fos/efeitos dos fármacos , Glucose/farmacologia , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , CinéticaRESUMO
OBJECTIVE: Inflammatory markers such as C-reactive protein (CRP) are associated with insulin resistance, adiposity, and type 2 diabetes. Whether inflammation causes insulin resistance or is an epiphenomenon of obesity remains unresolved. We aimed to determine whether first-degree relatives of type 2 diabetic subjects differ in insulin sensitivity from control subjects without a family history of diabetes, whether first-degree relatives of type 2 diabetic subjects and control subjects differ in CRP, adiponectin, and complement levels, and whether CRP is related to insulin sensitivity independently of adiposity. RESEARCH DESIGN AND METHODS: We studied 19 young normoglycemic nonobese first-degree relatives of type 2 diabetic subjects and 22 control subjects who were similar for age, sex, and BMI. Insulin sensitivity (glucose infusion rate [GIR]) was measured by the euglycemic-hyperinsulinemic clamp. Dual-energy X-ray absorptiometry determined total and abdominal adiposity. Magnetic resonance imaging measured abdominal adipose tissue volumes. RESULTS: First-degree relatives of type 2 diabetic subjects had a 20% lower GIR than the control group (51.8 +/- 3.9 vs. 64.9 +/- 4.6 micromol x min(-1) x kg fat-free mass(-1), P = 0.04). However, first-degree relatives of subjects with type 2 diabetes and those without a family history of diabetes had normal and comparable levels of CRP, adiponectin, and complement proteins. When the cohort was examined as a whole, CRP was inversely related to GIR (r = -0.33, P = 0.04) and adiponectin (r = -0.34, P = 0.03) and positively related to adiposity (P < 0.04). However, CRP was not related to GIR independently of fat mass. In contrast to C3 (r = 0.41, P = 0.009) and factor B (r = 0.43, P = 0.005), CRP was unrelated to factor D. CONCLUSIONS: The insulin-resistant state is not associated with changes in inflammatory markers or complement proteins in subjects at high risk of type 2 diabetes. Our study confirms a strong relationship between CRP and fat mass. Increasing adiposity and insulin resistance may interact to raise CRP levels.
Assuntos
Tecido Adiposo/anatomia & histologia , Diabetes Mellitus Tipo 2/genética , Inflamação/fisiopatologia , Resistência à Insulina/fisiologia , Adiponectina , Adulto , Índice de Massa Corporal , Peso Corporal , Proteína C-Reativa/análise , Família , Feminino , Humanos , Inflamação/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Valores de ReferênciaRESUMO
Allodynia, hyperalgesia and spontaneous pain are cardinal sensory signs of neuropathic pain. Clinically, many neuropathic pain patients experience affective-motivational state changes, including reduced familial and social interactions, decreased motivation, anhedonia and depression which are severely debilitating. In earlier studies we have shown that sciatic nerve chronic constriction injury (CCI) disrupts social interactions, sleep-wake-cycle and endocrine function in one third of rats, a subgroup reliably identified six days after injury. CCI consistently produces allodynia and hyperalgesia, the intensity of which was unrelated either to the altered social interactions, sleep-wake-cycle or endocrine changes. This decoupling of the sensory consequences of nerve injury from the affective-motivational changes is reported in both animal experiments and human clinical data. The sensory changes triggered by CCI are mediated primarily by functional changes in the lumbar dorsal horn, however, whether lumbar spinal changes may drive different affective-motivational states has never been considered. In these studies, we used microarrays to identify the unique transcriptomes of rats with altered social behaviours following sciatic CCI to determine whether specific patterns of lumbar spinal adaptations characterised this subgroup. Rats underwent CCI and on the basis of reductions in dominance behaviour in resident-intruder social interactions were categorised as having Pain & Disability, Pain & Transient Disability or Pain alone. We examined the lumbar spinal transcriptomes two and six days after CCI. Fifty-four 'disability-specific' genes were identified. Sixty-five percent were unique to Pain & Disability rats, two-thirds of which were associated with neurotransmission, inflammation and/or cellular stress. In contrast, 40% of genes differentially regulated in rats without disabilities were involved with more general homeostatic processes (cellular structure, transcription or translation). We suggest that these patterns of gene expression lead to either the expression of disability, or to resilience and recovery, by modifying local spinal circuitry at the origin of ascending supraspinal pathways.
Assuntos
Regulação da Expressão Gênica , Vértebras Lombares/lesões , Nervo Isquiático/lesões , Animais , Constrição Patológica , Vértebras Lombares/metabolismo , Vértebras Lombares/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/metabolismo , Nervo Isquiático/fisiopatologiaRESUMO
The history of food provision at the summer Olympic Games (OG) over the past century (1896-2008) provides insight into the evolution of sports nutrition research and the dietary strategies of athletes. Early research favoring protein as the main fuel for exercise was reflected in OG menus from 1932 to 1968. Despite conclusive research from the 1960s demonstrating the clear benefit of carbohydrate on exercise performance, a specific emphasis on carbohydrate-rich foods was not noted until the 1970s. Athlete food preferences and catering complexity evolved rapidly between 1970 and 2000, driven predominantly by a dramatic expansion of the OG and the emergence of systematic sports nutrition research. Nutritional advice by experts and sponsorship by food companies became increasingly important beginning with the 1984 Los Angeles OG. More recent developments include nutritional labeling of menu items and provision of a nutrition information desk (Barcelona 1992), demand for a "high-starch, low-fat menu" (Atlanta 1996), the addition of a dedicated menu website and the systematic gathering of information on athletes' apparent consumption (Sydney 2000), and appointment of the first international dietetic review committee (Beijing 2008). The history of catering at the OG tracks the evolution of sports nutrition practice from anecdotes and myth towards an established specialty in nutrition and dietetics grounded in evidence-based science.
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Serviços de Alimentação/história , Agências Internacionais , Esportes , Atletas/psicologia , Desempenho Atlético , Dieta , Preferências Alimentares , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Ciências da Nutrição/história , Estações do AnoRESUMO
It is well established that the NF-kappaB family of transcription factors serves a major role in controlling gene expression in response to T cell activation, but the genome-wide roles of individual family members remain to be determined. c-Rel, a member of the NF-kappaB family, appears to play a specific role in T cell function because T cells from c-Rel(-/-) animals are defective in their response to immune signals. We have used expression profiling to identify sets of genes that are affected by either deletion or overexpression of c-Rel in T cells. Very few of these genes exhibit a strong requirement for c-Rel; rather, c-Rel appears to modulate the expression of a large number of genes in these cells. The sets of c-Rel-affected genes are significantly enriched for genes containing consensus NF-kappaB/Rel sites in their proximal promoter regions. In addition, their promoters contain a higher average density of NF-kappaB/Rel sites compared with all genes represented on the microarrays. A transcriptional module comprised of two closely spaced c-Rel consensus sites is found with higher frequency in the c-Rel-affected gene sets and may represent an important control module for genes regulated by c-Rel or other NF-kappaB family members. We confirmed the importance of these findings on a subgroup of genes by using quantitative PCR to monitor gene expression as well as in vitro c-Rel/DNA binding assays and luciferase reporter assays. The c-Rel-regulated genes identified here support a role for c-Rel in inflammatory responses as well as in the promotion of cell growth and survival.
Assuntos
Linfócitos T CD4-Positivos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Marcação de Genes , NF-kappa B/fisiologia , Proteínas Proto-Oncogênicas c-rel/fisiologia , Animais , Sítios de Ligação/genética , Linhagem Celular Tumoral , Humanos , Células Jurkat , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-rel/deficiência , Proteínas Proto-Oncogênicas c-rel/genética , Proteínas Proto-Oncogênicas c-rel/metabolismoAssuntos
Endotoxemia/metabolismo , Trato Gastrointestinal/microbiologia , Inflamação/fisiopatologia , Gordura Intra-Abdominal/metabolismo , Doenças Metabólicas/fisiopatologia , Metagenoma , Animais , Distribuição da Gordura Corporal , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/metabolismo , Humanos , Macrófagos/imunologia , Doenças Metabólicas/imunologia , Doenças Metabólicas/microbiologia , Obesidade/imunologia , Obesidade/microbiologia , Obesidade/fisiopatologiaRESUMO
The intracellular and intramembrane profiles of fatty acids mirror those of dietary fat intake. The properties of transporter and receptor proteins embedded within cell membranes are influenced by the composition of the phospholipid membrane of cells. Many cell-signalling pathways involve lipids or lipid-derived molecules. Specific fatty acids are increasingly being identified as key regulators of gene expression and tissue differentiation.
Assuntos
Membrana Celular/fisiologia , Gorduras na Dieta/farmacologia , Ácidos Graxos/fisiologia , Transdução de Sinais/fisiologia , HumanosRESUMO
This study aimed to determine whether maternal protein restriction alters hepatic glycogen metabolism. Mated female rats were fed diets containing 20% protein throughout pregnancy and lactation (CONT), 8% protein throughout pregnancy and lactation (LP), or 8% protein during the last week of pregnancy only and lactation (LLP). Weights and lengths were reduced in the LLP and LP offspring compared with the CONT offspring. The LLP and LP offspring demonstrated reduced insulin concentrations at both 10 and 26 d and also failed to show the increase in insulin seen with time in the CONT offspring. Serum glucose and leptin levels increased with time but were not different among the groups; however, in relation to adiposity leptin levels were greater in the LLP and LP offspring at 26 d. The LLP and LP offspring had increased hepatic glycogen at day 10 (CONT, 75.1 +/- 9.8; LLP, 103.4 +/- 11.0; LP, 116.0 +/- 18.4 glucose residues/g tissue) and d 26 (CONT, 183.1 +/- 38.9; LLP, 395.3 +/- 16.8; LP, 396.6 +/- 15.1 glucose residues/g tissue). Glycogen synthase expression was increased in the LLP and LP offspring at 10 d but not 26 d; glucose transporter 2 and glycogen phosphorylase expressions were not different at either time. At 26 d glycogen synthase activity was not different; however, glycogen phosphorylase a activity was reduced. The enhanced capacity to store glycogen despite reductions in insulin secretion suggests increased insulin sensitivity possibly acting with an alternative non-insulin-dependent glycogen storage mechanism.