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1.
Can J Diet Pract Res ; 84(3): 154-158, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37071489

RESUMO

It is important that breast cancer patients know where they can access evidence-based nutrition information because misinformation may lead to confusion for patients regarding dietary requirements, as well as potentially causing harm to health. There are gaps in knowledge about where and when patients seek nutrition information. Our exploratory study used telephone interviews to investigate where patients with breast cancer obtained nutrition information pre and postdiagnosis, and their preferred sources and timing for receiving nutrition information. We interviewed 29 women diagnosed with breast cancer who had attended the Cross Cancer Institute in Edmonton, Alberta. The structured interview included 13 closed-ended questions and 1 open-ended question. Interviews revealed that motives for seeking nutrition information changed between pre and postdiagnosis, but the sources did not. The majority of participants did not access a registered dietitian (RD) postdiagnosis but did specify that meeting with a RD would be their preferred source of information. Responses varied for the preferred sources and timing of nutrition information provision. Our study suggests that further research is necessary to know how to best meet the nutrition information needs of patients diagnosed with breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Estado Nutricional , Comunicação , Alberta
2.
J Am Coll Health ; 71(5): 1374-1380, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-34469260

RESUMO

Objective: Prevalence of food insecurity in NCAA DIII student-athletes was assessed via an anonymous, online survey (n = 787) in February of 2020. Participants: Participants were mainly female, 18-21 years old, self-identified as white, lived on campus and had a campus meal plan. Methods: Food security was assessed using an anonymous, online survey based off of the USDA 6-item short form food security survey. Results: Overall prevalence of food insecurity was 14.7% with Hispanic students, Black students, those without a meal plan, recipients of a Pell grant, first generation college students and those experiencing food insecurity prior to enrolling in college being at higher risk. A majority of respondents felt lack of access to food impacted their academic and athletic performance, as well as overall health and cited timing of practices and games overlapping with dining hall hours as a key contributor. Conclusion: Based off of these results, educational programs and resources should be targeted toward these high-risk groups to help ensure consistent access to safe and healthy food for student-athletes.


Assuntos
Atletas , Estudantes , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Masculino , Prevalência , Universidades , Insegurança Alimentar , Abastecimento de Alimentos
3.
Adv Nutr ; 13(4): 1118-1130, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34918023

RESUMO

Body composition parameters are not captured by measures of body mass, which may explain inconsistent associations between body weight and prostate cancer (PC) risk. The objective of this systematic review was to characterize the association between fat mass (FM) and fat-free mass (FFM) parameters and PC risk. A search of PubMed, Embase, and Web of Science identified case-control and cohort studies that measured body composition in relation to PC risk. Methodological quality was assessed using the Newcastle-Ottawa Scale (NOS). Thirteen observational studies were included, of which 8 were case-control studies (n = 1572 cases, n = 1937 controls) and 5 were prospective cohort studies (n = 7854 incident cases with PC). The NOS score was 5.9 ± 1.1 for case-control studies and 8.4 ± 1.3 for cohort studies. The most common body composition technique was bioelectrical impedance analysis (n = 9 studies), followed by DXA (n = 2), computed tomography (n = 2), air displacement plethysmography (n = 1), and MRI (n = 1). No case-control studies reported differences in %FM between PC cases and controls and no consistent differences in FM or FFM (in kilograms) were observed. Two out of 5 cohort studies reported that higher %FM was associated with lower PC risk. Conversely, 3 cohort studies reported a greater risk of being diagnosed with advanced/aggressive PC with higher FM (expressed in kilograms, %FM, or fat distribution). Two out of 4 studies (both case-control and cohort) found that higher abdominal adipose tissue was associated with increased PC risk. In conclusion, although results were inconsistent, there is some evidence that FM may be negatively associated with total PC risk but positively associated with the risk of advanced/aggressive PC; modest evidence suggests that abdominal adipose tissue may increase the risk of PC. Future work should elucidate unique patterns of FM distribution and PC risk to triage men at risk for developing PC. This study protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database as CRD42019133388.


Assuntos
Tecido Adiposo , Neoplasias da Próstata , Humanos , Masculino , Absorciometria de Fóton , Tecido Adiposo/metabolismo , Composição Corporal , Índice de Massa Corporal , Impedância Elétrica , Estudos Prospectivos , Neoplasias da Próstata/etiologia , Estudos Observacionais como Assunto
4.
Nutr Res ; 89: 45-55, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33894660

RESUMO

Visual analogue scales (VAS) have commonly been used to assess appetite in children 8 years and older; however, these tools have been considered unreliable for children 7 years old and under. The objective of this pilot study was to develop a picture-based appetite assessment (PBAA) tool for children aged 4-10 years and pilot test it compared to a VAS-based appetite assessment. The study hypothesis was that the PBAA scores would decrease following the consumption of an ad libitum snack compared to the scores in the fasted state in children 4 to 10 years old; furthermore, there would be a good level of agreement (intraclass correlation coefficients >0.75) between the appetite scores by the PBAA and VAS tools in children aged 8 years or older. At Visit 1, in a fasted state, all children (n = 15) completed the PBAA. Children who were 8-10 years old (n = 8) also completed the VAS-based appetite assessment. Then, an ad libitum snack was provided, and appetite assessments were repeated at 5-, 30- and 60-minutes post-snack. The same assessments were completed at visit 2 pre (fasting)- and post-consumption of a snack containing 25% of the amount consumed at visit 1 (limited snack). PBAA scores were different across time (P < .001) and between types of meal (ad libitum vs limited snack) (P = .015) in all children. A good agreement between the PBAA and VAS scores at 30 and 60 minutes after both types of meal was found (intraclass correlation coefficients >0.75). The PBAA tool was able to detect expected changes in appetite sensations and was in good agreement with the VAS instrument.


Assuntos
Apetite , Criança , Pré-Escolar , Jejum , Feminino , Humanos , Fome , Masculino , Refeições , Projetos Piloto , Saciação , Sensação , Lanches , Escala Visual Analógica
5.
Curr Dev Nutr ; 5(3): nzab016, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33817544

RESUMO

The aim of this study was to explore the feasibility of measuring a postprandial increase in energy expenditure (ΔEE) using a state-of-the-art whole-body calorimetry unit (WBCU) in children and youth with Prader-Willi syndrome (PWS). Five participants (aged 10-25 y) received both a standard and a high-protein diet in a random order (crossover design). Resting energy expenditure, postprandial ΔEE 6 h after intake of a standard [15% of total energy (TE)] and a high-protein (30% TE) meal, and respiratory exchange ratio (RER) were measured in a WBCU. No differences were observed in ΔEE comparing the 2 meals. Mean RER was lower following the high-protein meal (0.80 ± 0.01) compared with the standard meal (0.87 ± 0.02) (P = 0.009). Despite the high participant burden, it was feasible to conduct this metabolic test in children and youth with PWS. This study paves the way for further studies targeting EE in this patient population.

6.
Clin Endocrinol (Oxf) ; 93(5): 579-589, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32638409

RESUMO

BACKGROUND: The effects of dietary macronutrients on orexigenic and anorexigenic hormones in children are poorly understood. OBJECTIVE: To explore effects of varying dietary macronutrients on appetite-regulating hormones [acyl ghrelin (AG) and desacyl ghrelin (DAG), glucagon-like peptide 1 (GLP-1), peptide tyrosine tyrosine (PYY) and insulin] in children with PWS and healthy children (HC). DESIGN: Randomized, cross-over experiments compared two test diets [high protein-low carbohydrate (HP-LC) and high protein-low fat (HP-LF)] to a STANDARD meal (55% carbohydrate, 30% fat, 15% protein). Experiment 1 included ten children with PWS (median age 6.63 years; BMI z 1.05); experiment 2 had seven HC (median age 12.54 years; BMI z 0.95). Blood samples were collected at baseline and at 60-minute intervals for 4 hours. Independent linear mixed models were adjusted for age, sex and BMI z-score. RESULTS: Fasting and post-prandial AG and DAG concentrations are elevated in PWS children; the ratio of AG/DAG is normal. Food consumption reduced AG and DAG concentrations in both PWS and HC. GLP-1 levels were higher in PWS after the HP-LC and HP-LF meals than the STANDARD meal (P = .02-0.04). The fasting proinsulin to insulin ratio (0.08 vs 0.05) was higher in children with PWS (P = .05) than in HC. Average appetite scores in HC declined after all three meals (P = .02) but were lower after the HP-LC and HP-LF meals than the STANDARD meal. CONCLUSION: Altered processing of proinsulin and increased GLP-1 secretion in children with PWS after a high protein meal intake might enhance satiety and reduce energy intake.


Assuntos
Síndrome de Prader-Willi , Glicemia , Criança , Jejum , Grelina , Humanos , Nutrientes
7.
Front Physiol ; 11: 583825, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33551830

RESUMO

Sarcopenic obesity is associated with several negative health outcomes. However, the prevalence of this condition - and the relationship to physical performance parameters - varies across definitions. The aim of this cross-sectional investigation was to describe the prevalence of sarcopenic obesity using different published definitions and their relationship with handgrip strength and walking speed in older Canadian adults. Individuals aged 65+ in the Canadian Longitudinal Study on Aging (n = 11,803; 49.6% male, 50.4% female) were included. Body composition was measured using dual X-ray absorptiometry. Sarcopenic obesity was defined using 29 definitions. Low handgrip strength was identified as < 27 kg in males and < 16 kg in females and poor physical performance was defined as gait speed ≤ 0.8 m/s. The prevalence of sarcopenic obesity ranged from 0.1 to 85.3% in males, and from 0 to 80.4% in females. Sarcopenic obesity was frequently associated with low handgrip strength (p < 0.05) in both males (14/17 definitions, 82.4%) and females (21/29 definitions, 72.4%). In very few definitions, sarcopenic obesity was associated with slow gait speed (males: 1/17 definitions [6.7%]; females: 2/29 [6.9%]). In conclusion, the prevalence of sarcopenic obesity varied greatly according to definitions and sarcopenic obesity was frequently associated with low handgrip strength.

8.
Am J Med Genet A ; 176(11): 2309-2317, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30216657

RESUMO

Dietary management is important to prevent severe obesity in individuals with Prader-Willi syndrome (PWS); however, few studies have examined dietary intake and quality in youth with PWS. Our objective was to estimate intake of essential nutrients and diet quality in youth with PWS compared to those without PWS. Three-day food records were used to estimate intake of energy, nutrients, nutrient-density, foods, and adherence to healthy eating guidelines. Data were presented as medians and interquartile ranges with Mann-Whitney U and Fisher's test used to compare between groups with p < .05 considered significant. Youth with (n = 23) and without (n = 23) PWS were similar in age and sex distribution. The PWS group had a lower energy intake (p ≤ .001), higher nutrient density (p = .003), and better adherence to guidelines (p = .007) compared to the control group. The proportion with nutrient intake from food below Estimated Average Requirement or Adequate Intake were similar between groups. Fiber, vitamin D, calcium, and potassium intake were below recommendations in 50% or more in both groups. The inclusion of supplement intake lowered the proportion below recommendations, except for fiber and potassium. Youth with PWS had a similar nutrient intake as those without PWS despite a lower energy intake, which could be attributed to higher diet quality. However, more than half of youth with PWS were at risk of inadequate fiber, vitamin D, calcium, and potassium intake. A greater emphasis on nutrient-dense foods would improve nutrient intake, but supplements may be warranted in youth with PWS who do not meet recommendations.


Assuntos
Dieta , Ingestão de Alimentos , Síndrome de Prader-Willi/epidemiologia , Adolescente , Bebidas , Estudos de Casos e Controles , Criança , Dieta Saudável , Suplementos Nutricionais , Ingestão de Energia , Feminino , Humanos , Masculino , Micronutrientes , Nutrientes
9.
Adv Nutr ; 8(6): 905-915, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29141973

RESUMO

Prader-Willi syndrome (PWS) is a rare genetic disorder associated with excessive weight gain. Hyperphagia associated with PWS may result in higher energy intake, but alterations in energy expenditure may also contribute to energy imbalance. The purpose of this critical literature review is to determine the presence of alterations in energy expenditure in individuals with PWS. Ten studies that measured total energy expenditure (TEE), resting energy expenditure (REE), sleep energy expenditure (SEE), activity energy expenditure (AEE), and diet induced thermogenesis (DIT) were included in this review. The studies provided evidence that absolute TEE, REE, SEE, and AEE are lower in individuals with PWS than in age-, sex-, and body mass index-matched individuals without the syndrome. Alterations in lean body mass and lower physical activity amounts appear to be responsible for the lower energy expenditure in PWS rather than metabolic differences. Regardless of the underlying mechanism for lower TEE, the estimation of energy requirements with the use of equations derived for the general population would result in weight gain in individuals with PWS. The determination of energy requirements for weight management in individuals with PWS requires a more comprehensive understanding of energy metabolism. Future studies should aim to comprehensively profile all specific components of energy expenditure in individuals with PWS with the use of appropriately matched controls and gold standard methods to measure energy metabolism and body composition. One component of energy expenditure that is yet to be explored in detail in PWS is DIT. A reduced DIT (despite differences in fat free mass), secondary to hormonal dysregulation, may be present in PWS individuals, leading to a reduced overall energy expenditure. Further research exploring DIT in PWS needs to be conducted. Dietary energy recommendations for weight management in PWS have not yet been clearly established.


Assuntos
Metabolismo Energético/fisiologia , Síndrome de Prader-Willi/fisiopatologia , Índice de Massa Corporal , Dieta/efeitos adversos , Ingestão de Energia/fisiologia , Humanos , Descanso/fisiologia , Termogênese/fisiologia
10.
Int J Mol Sci ; 18(3)2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28264487

RESUMO

Prader-Willi syndrome (PWS), a rare genetic disorder caused by the lack of expression of paternal genes from chromosome 15q11-13, has been investigated for autism spectrum disorder (ASD) symptomatology in various studies. However, previous findings have been variable, and no studies investigating ASD symptomatology in PWS have exclusively studied children. We aimed to characterize social communication functioning and other ASD-related symptoms in children with PWS, and assessed agreement across measures and rates of ASD diagnosis. Measures included the Autism Diagnostic Observation Schedule-2 (ADOS-2), the Social Communication Questionnaire (SCQ), Social Responsiveness Scale-2 (SRS-2), Social Skills Improvement System-Rating Scales (SSIS-RS), and the Vineland Adaptive Behavioral Scales-II (VABS-II). General adaptive and intellectual skills were also assessed. Clinical best estimate (CBE) diagnosis was determined by an experienced developmental pediatrician, based on history and review of all available study measures, and taking into account overall developmental level. Participants included 10 children with PWS, aged 3 to 12 years. Three of the 10 children were male and genetic subtypes were two deletion (DEL) and eight uniparental disomy (UPD) (with a total of 6 female UPD cases). Although 8 of the 10 children exceeded cut-offs on at least one of the ASD assessments, agreement between parent questionnaires (SCQ, SRS-2, SSIS-RS) and observational assessment (ADOS-2) was very poor. None of the children were assigned a CBE diagnosis of ASD, with the caveat that the risk may have been lower because of the predominance of girls in the sample. The lack of agreement between the assessments emphasizes the complexity of interpreting ASD symptom measures in children with PWS.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Fenótipo , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/psicologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Testes Psicológicos , Reprodutibilidade dos Testes
11.
Metabolism ; 69: 67-75, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28285653

RESUMO

INTRODUCTION: Magnetic resonance imaging (MRI) provides detailed assessment of body composition compartments. No studies have employed state-of-the-art MRI methods to accurately examine abdominal adipose tissue (AT) and skeletal muscle in youth with Prader-Willi syndrome (PWS). Therefore, this study aimed to describe AT distribution and skeletal muscle in the abdominal region of youth with PWS using MRI. METHODS: Anthropometric measures and whole-abdominal T1-weighted MRI were performed in sixteen (5 males and 11 females) youth diagnosed with PWS, and seventeen (10 males and 7 females) youth who did not have PWS (controls). Volume of subcutaneous, visceral, intermuscular, and total AT, and skeletal muscle in the abdominal region were quantified using a semiautomatic procedure. Results were summarized using median and interquartile range (IQR, 25th-75th), and ANCOVA test was used (with age and sex as covariates) to examine differences in body composition compartments between PWS and control group. RESULTS: PWS group had similar age (10.5, 6.6-13.9 vs. 12.8, 10.0-14.4years; P=0.14) and BMI z-score (0.5, 0.2-1.3 vs. 0.2, -0.3 to 1.0; P=0.33) when compared with controls. Significant differences were observed in absolute volumes of total AT (PWS: 4.1, 2.0-6.6L; control: 2.9, 2.0-4.5L; P=0.01), subcutaneous AT (PWS: 2.8, 1.4-4.8L; control: 1.8, 1.1-3.2L; P=0.01), and intermuscular AT (PWS: 0.3, 0.1-0.4L; control: 0.3, 0.2-0.3L; P<0.005). Visceral AT/subcutaneous AT was lower in PWS (0.4, 0.3-0.5) compared to controls (0.5, 0.4-0.6), P=0.01. In addition, skeletal muscle volume was lower in PWS (1.5, 1.0-2.6L) compared to controls (3.1, 1.6-3.9L), P=0.03. Ratios of abdominal AT compartments to skeletal muscle were all higher in PWS compared to controls (all P<0.005). CONCLUSIONS: PWS youth have greater abdominal adiposity, particularly subcutaneous AT and intermuscular AT, and lower volume of skeletal muscle compared to controls. The decreased ratio of visceral AT/subcutaneous AT in youth with PWS suggests an improved metabolic profile for the level of adiposity present; however, elevated ratios of AT to skeletal muscle suggest a sarcopenic obesity-like phenotype, which could lead to worse health outcomes.


Assuntos
Composição Corporal , Imageamento por Ressonância Magnética/métodos , Síndrome de Prader-Willi/metabolismo , Gordura Abdominal/metabolismo , Adolescente , Fatores Etários , Antropometria , Distribuição da Gordura Corporal , Índice de Massa Corporal , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Músculo Esquelético/metabolismo , Fenótipo , Fatores Sexuais
12.
Physiol Behav ; 164(Pt A): 54-7, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27235736

RESUMO

Perceptual-biases are important for understanding an animal's natural history, identifying potential ecological traps, and for developing effective means to monitor individuals and populations. Despite research demonstrating anurans having a positive phototactic response towards blue colors, we do not yet understand if color cues are used functionally beyond sexual selection. The aim of our study was to determine if color cues are used in selecting microhabitat, and if anuran's blue-positive phototactic response could increase selection of artificial PVC refugia used to monitor cryptic camouflaging anuran species. We captured 32 Cope's Gray Treefrogs and placed them in mesh enclosures with three PVC tubes painted blue, brown, and white. Concurrently, we placed blue, brown, or unpainted white PVC tubes in stratified arrays around a treefrog breeding pond, and counted the number of occasions treefrogs occupied different colored PVC tubes. In the confined choice experiment, treefrogs selected blue tubes (48.3%) significantly more often than brown (28.5%) or white (23.2%) tubes. Our field experiment mirrored these findings (52.0% of capture events in blue, 29.0% in brown, and 19.0% in unpainted white tubes). Our results suggest color influences Cope's Gray Treefrog microhabitat selection, and they utilize color vision when choosing refugia. We demonstrate simple, small changes based on perceptual-biases can induce behaviors that may in turn have large impacts on sampling techniques used in monitoring and inventorying. Incorporating non-traditional physiological measures into animal inventorying and monitoring programs can be used in the future to improve conservation efforts.


Assuntos
Anuros/fisiologia , Percepção de Cores/fisiologia , Cor , Hábitos , Animais , Sinais (Psicologia) , Especificidade da Espécie
13.
Appl Physiol Nutr Metab ; 33(1): 1-11, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18347648

RESUMO

Patients with advanced and incurable cancer are a compelling group. Questions and comments that these individuals and their families have may include: "My daughter is expecting our first grandchild in 3 months--can I hope to see our new family member?"; "I can't keep any food down--is there anything I can do?"; "I am worried about losing so much weight, and feeling tired and weak--is there anything that may help?"; "Will I suffer a lot?". Indeed, the most pressing concerns of the patient relate to predictions about survival and control of symptoms. The clinician taking care of the patient may wonder what is the utility or futility of home parenteral nutrition (HPN) in both the individual with advanced cancer and in this population of patients at large, whether there is potential for harm such as increasing the burden of care or prolonging suffering, and how to optimize care and communication with the patient and their families. The nutrition scientist may want to know what the implications of advanced cancer are on nutrient requirements and utilization, whether there are markers that would differentiate between cachexia and simple starvation, and whether it is possible to use specific nutrients to modify the disease process. This review will provide insights into the understanding of the role of HPN in advanced cancer and opportunities for further investigation.


Assuntos
Desnutrição/dietoterapia , Neoplasias/complicações , Cuidados Paliativos/tendências , Nutrição Parenteral no Domicílio/tendências , Humanos , Desnutrição/etiologia , Desnutrição/psicologia , Neoplasias/psicologia , Cuidados Paliativos/psicologia , Nutrição Parenteral no Domicílio/psicologia , Guias de Prática Clínica como Assunto
14.
J Nutr ; 136(1 Suppl): 237S-42S, 2006 01.
Artigo em Inglês | MEDLINE | ID: mdl-16365090

RESUMO

Many of the features of BCAA metabolism in the tumor-bearing state are similar to the other disease states that feature involuntary weight loss and skeletal muscle atrophy. These states are generally characterized by altered BCAA availability (low BCAA intakes, elevated rates of BCAA oxidation, and gluconeogenesis), which are concurrent with activation of proteolysis and suppression of protein synthesis in skeletal muscle and ultimately lead to erosion of lean tissue mass. These features in turn imply BCAA deficiency compared with whole-body requirements and are the basis of suggestions for dietary supplementation with BCAA or their metabolites. Recent studies on BCAA supplementation in cancer focus on leucine and its derivative, beta-methyl beta-hydroxybutyrate, as regulators of skeletal muscle metabolism, although their relative efficacy is unknown. However, what would otherwise be a relatively straightforward consideration of amino acid supply and demand is confounded by the presence of the tumor and its potential utilization of BCAA for its proliferative and invasive activities. Positron emission tomography with (11)C-leucine, used for in vivo tumor imaging, points to the high avidity of tumor amino acid uptake. These features have incited research in opposing directions, probing BCAA deprivation, with a view to limiting tumor growth, as well as BCAA supplementation, with a view to supporting maintenance of host lean tissue. No clear conclusion is presently available from the sum of these efforts. Animal models with relevant clinical features are essential to determine if amino acid therapy can alter the balance between the host and the tumor in a manner that favors the host overall.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Neoplasias Experimentais/metabolismo , Aminoácidos de Cadeia Ramificada/administração & dosagem , Animais , Caquexia/metabolismo , Modelos Animais de Doenças , Humanos , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Neoplasias Experimentais/tratamento farmacológico
15.
Am J Physiol Endocrinol Metab ; 289(4): E527-33, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15941785

RESUMO

Chronic or acute inflammation may participate in the etiology of cancer cachexia. To investigate the interaction between tumor and a secondary inflammatory stimulus on muscle wasting, rats with and without tumors (Yoshida ascites hepatoma) received low doses of endotoxin (LPS, 400 microg/kg sc) or saline. Nitrogen balance was measured 24 h before and after LPS/saline. Epitrochlearis muscle was used to measure in vitro protein metabolism, and gastrocnemius muscle was used for quantification of the mRNA for components of the ubiquitin proteolytic pathway. The YAH reduced muscle mass (P = 0.002), increased muscle protein degradation (P = 0.042), and elevated mRNA expression of components of the ubiquitin proteolytic pathway (P < 0.01) including ubiquitin, ubiquitin-conjugating enzyme E2(14k), and ubiquitin ligases muscle RING Finger 1 and atrogin-1. Although the selected low dose of LPS had no impact on protein metabolism in control rats, LPS in rats bearing YAH caused weight loss (P = 0.0007), lowered nitrogen balance (P = <0.0001), and increased muscle protein degradation (P = 0.0336). In conclusion, the presence of a tumor can potentiate whole body and muscle-specific catabolic losses of protein in response to a stimulus that is not catabolic in healthy animals. This effect might be dependent on the inflammatory nature of the tumor.


Assuntos
Carcinoma Hepatocelular/imunologia , Citocinas/imunologia , Lipopolissacarídeos/administração & dosagem , Proteínas Musculares/imunologia , Músculo Esquelético/imunologia , Músculo Esquelético/patologia , Proteínas de Neoplasias/imunologia , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Masculino , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
16.
J Nutr ; 133(6): 1875-81, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12771332

RESUMO

Our aim was to examine the effect of acute inflammation localized in the colon and early macronutrient restriction on protein synthesis in a piglet model. In a 2 x 2 factorial design, piglets (n = 32) were fed an adequate or macronutrient-restricted diet with or without dextran sulfate-induced colitis for 7 d. The stable isotope tracer L-[5,5,5-(2)H(3)]leucine was infused to determine protein kinetics at the whole-body level and synthesis of tissue and plasma proteins. In the well-nourished state, colitis did not affect weight gain or protein kinetics except for an increase in albumin synthesis (P < 0.05). Macronutrient restriction alone caused a general slowing of protein metabolism including decreased weight gain (P < 0.0004), whole-body protein turnover (P < 0.0001), and liver (P < 0.01) and plasma protein (P < 0.03) synthesis. However, in the presence of macronutrient restriction, colitis compromised weight gain further (P < 0.02) and decreased muscle protein synthesis (P < 0.05) due to a redistribution of protein metabolism that supported enhanced synthesis of plasma proteins. The increased contribution of plasma protein synthesis to whole-body protein turnover was attributable mainly to increased synthesis of albumin (P < 0.006). Concentrations of plasma proteins were unaffected despite dramatic changes in their synthesis rates, thereby underestimating the effects of malnutrition and colitis on protein metabolism. Increased synthesis of plasma proteins, particularly the negative acute phase reactant albumin, compromises weight gain and muscle protein synthesis only when macronutrient intake is inadequate, underscoring the role of adequate nutrition in preventing growth impairment and muscle wasting in acute inflammation. These results suggest that the hypoalbuminemia of inflammatory bowel disease should not be attributed to decreased synthesis.


Assuntos
Albuminas/biossíntese , Fenômenos Fisiológicos da Nutrição Animal , Animais Recém-Nascidos/metabolismo , Colite/metabolismo , Proteínas Musculares/biossíntese , Distúrbios Nutricionais/metabolismo , Animais , Proteínas Sanguíneas/metabolismo , Ingestão de Alimentos , Proteínas/metabolismo , Suínos , Aumento de Peso
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