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3.
Front Nutr ; 9: 874312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592635

RESUMO

Globally, we are failing to meet numerous nutritional, health, and environmental targets linked to food. Defining food composition in its full chemical and quantitative diversity is central to data-driven decision making for supporting nutrition and sustainable diets. "Foodomics"-the application of omics-technology to characterize and quantify biomolecules to improve wellbeing-has the potential to comprehensively elucidate what is in food, how this composition varies across the food system, and how diet composition as an ensemble of foods guides outcomes for nutrition, health, and sustainability. Here, we outline: (i) challenges of evaluating food composition; (ii) state-of-the-art omics technology and innovations for the analysis of food; and (iii) application of foodomics as a complementary data-driven approach to revolutionize nutrition and sustainable diets. Featuring efforts of the Periodic Table of Food Initiative, a participatory effort to create a globally shared foodomics platform, we conclude with recommendations to accelerate foodomics in ways that strengthen the capacity of scientists and benefit all people.

4.
Mol Cell Proteomics ; 18(11): 2165-2177, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31409668

RESUMO

Secretory Immunoglobulin A (SIgA) is central to mucosal immunity: represents one of the main immunological mechanisms of defense against the potential attack of pathogens. During lactation SIgA is produced by plasmablasts in the mammary gland and is present in breast milk, playing a vital role in the passive immunity of the newborn. Interestingly, the different components of SIgA are highly N-glycosylated, and these N-Glycans have an essential role in health maintenance. In this work, we performed a glycomic study to compare N-glycosylation of SIgA purified from mature breast milk and saliva, and plasma IgA from the same lactating participants. Our results revealed a greater diversity than previously reported, with 89 glycan compositions that may correspond to over 250 structures. Among these glycans, 54 glycan compositions were characterized as body-fluid specific. Most of these unique N-Glycan compositions identified in SIgA from mature milk and IgA from plasma were fucosylated and both fucosylated and sialylated species, whereas in salivary SIgA the unique structures were mainly undecorated complex N-Glycans. In addition, we evaluated the effect of delivery mode on (S)IgA glycosylation. Lactating participants who had given birth by vaginal delivery presented an increased proportion of high mannose and fucosylated glycans in salivary SIgA, and selected high mannose, fucosylated, sialylated, and both fucosylated and sialylated glycans in plasma IgA, indicating that the hormonal changes during vaginal delivery could affect plasma and saliva IgA. These results reveal the structural details that provide a new dimension to the roles of (S)IgA N-Glycans in different tissues, and especially in maternal and new-born protection and infant development. The design of optimal recombinant IgA molecules specifically targeted to protect mucosal surfaces will need to include this dimension of structural detail.


Assuntos
Imunoglobulina A Secretora/análise , Imunoglobulina A/análise , Lactação , Leite Humano/metabolismo , Plasma/metabolismo , Polissacarídeos/análise , Saliva/metabolismo , Feminino , Glicosilação , Humanos
5.
Am J Clin Nutr ; 110(3): 769-779, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31274142

RESUMO

Nationally representative data from mother-child dyads that capture human milk composition (HMC) and associated health outcomes are important for advancing the evidence to inform federal nutrition and related health programs, policies, and consumer information across the governments in the United States and Canada as well as in nongovernment sectors. In response to identified gaps in knowledge, the National Institute of Diabetes and Digestive and Kidney Diseases of the NIH sponsored the "Workshop on Human Milk Composition-Biological, Environmental, Nutritional, and Methodological Considerations" held 16-17 November 2017 in Bethesda, Maryland. Through presentations and discussions, the workshop aimed to 1) share knowledge on the scientific need for data on HMC; 2) explore the current understanding of factors affecting HMC; 3) identify methodological challenges in human milk (HM) collection, storage, and analysis; and 4) develop a vision for a research program to develop an HMC data repository and database. The 4 workshop sessions included 1) perspectives from both federal agencies and nonfederal academic experts, articulating scientific needs for data on HMC that could lead to new research findings and programmatic advances to support public health; 2) information about the factors that influence lactation and/or HMC; 3) considerations for data quality, including addressing sampling strategies and the complexities in standardizing collection, storage, and analyses of HM; and 4) insights on how existing research programs and databases can inform potential visions for HMC initiatives. The general consensus from the workshop is that the limited scope of HM research initiatives has led to a lack of robust estimates of the composition and volume of HM consumed and, consequently, missed opportunities to improve maternal and infant health.


Assuntos
Dieta/normas , Lactação/fisiologia , Fenômenos Fisiológicos da Nutrição Materna , Leite Humano/química , Canadá , Feminino , Humanos , Estados Unidos
6.
J Invest Dermatol ; 134(1): 192-202, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23867896

RESUMO

CD1d is a major histocompatibility complex class 1-like molecule that regulates the function and development of natural killer T (NKT) cells. Previously, we identified a critical role for the CD1d-NKT cell arm of innate immunity in promoting the development of UVB-induced p53 mutations, immune suppression, and skin tumors. Sunburn, an acute inflammatory response to UVB-induced cutaneous tissue injury, represents a clinical marker for non-melanoma skin cancer (NMSC) risk. However, the innate immune mechanisms controlling sunburn development are not considered relevant in NMSC etiology, and remain poorly investigated. Here we found that CD1d knockout (CD1d(-/-)) mice resist UVB-induced cutaneous tissue injury and inflammation compared with wild-type (WT) mice. This resistance was coupled with a faster epithelial tissue healing response. In contrast, the skins of UVB-irradiated invariant NKT cell-knockout (Jα18(-/-)) and NKT cell-deficient (TCRα(-/-)) mice, which express CD1d but are deficient in CD1d-dependent NKT cells, exhibited as much cutaneous tissue injury and inflammation as WT mice. In the absence of NKT cells, CD1d-deficient keratinocytes, dendritic cells, and macrophages exhibited diminished basal and stress-induced levels of pro-inflammatory mediators. Thus, our findings identify an essential role for CD1d in promoting UVB-induced cutaneous tissue injury and inflammation. They also suggest sunburn and NMSC etiologies are immunologically linked.


Assuntos
Antígenos CD1d/imunologia , Dermatite/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Queimadura Solar/imunologia , Raios Ultravioleta/efeitos adversos , Animais , Antígenos CD1d/genética , Dermatite/patologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Mediadores da Inflamação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pele/patologia , Pele/efeitos da radiação , Queimadura Solar/patologia , Cicatrização/imunologia
7.
J Dairy Res ; 79(1): 66-75, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22114848

RESUMO

Genes in the sterol regulatory element-binding protein-1 (SREBP1) pathway play a central role in regulation of milk fat synthesis, especially the de-novo synthesis of saturated fatty acids. SCD, a SREBP-responsive gene, is the key enzyme in the synthesis of monounsaturated fatty acids in the mammary gland. In the present study, we discovered SNP in candidate genes associated with this signalling pathway and SCD to identify genetic markers that can be used for genetic and metabolically directed selection in cattle. We resequenced six candidate genes in the SREBP1 pathway (SREBP1, SCAP, INSIG1, INSIG2, MBTPS1, MBTPS2) and two genes for SCD (SCD1 and SCD5) and discovered 47 Tag SNP that were used in a marker-trait association study. Milk and blood samples were collected from Holstein cows in their 1st or 2nd parity at 100-150 days of lactation. Individual fatty acids from C4 to C20, saturated fatty acid (SFA) content, monounsaturated fatty acid content, polyunsaturated fatty acid content and desaturase indexes were measured and used to perform the asociation analysis. Polymorphisms in the SCD5 and INSIG2 genes were the most representative markers associated with SFA/unsaturated fatty acid (UFA) ratio in milk. The analysis of desaturation activity determined that markers in the SCD1 and SCD5 genes showed the most significant effects. DGAT1 K232A marker was included in the study to examine the effect of this marker on the variation of milk fatty acids in our Holstein population. The percentage of variance explained by DGAT1 in the analysis was only 6% of SFA/UFA ratio. Milk fat depression was observed in one of the dairy herds and in this particular dairy one SNP in the SREBP1 gene (rs41912290) accounted for 40% of the phenotypic variance. Our results provide detailed SNP information for key genes in the SREBP1 signalling pathway and SCD that can be used to change milk fat composition by marker-assisted breeding to meet consumer demands regarding human health, as well as furthering understanding of technological aspects of cows' milk.


Assuntos
Bovinos/metabolismo , Leite/química , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Bovinos/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Feminino , Regulação da Expressão Gênica/fisiologia , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Transdução de Sinais/fisiologia
8.
J Proteome Res ; 10(5): 2612-24, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21469647

RESUMO

Extensive site-specific glycosylation analysis of individual glycoproteins is difficult due to the nature and complexity of glycosylation in proteins. In protein mixtures, these analyses are even more difficult. We present an approach combining nonspecific protease digestion, nanoflow liquid chromatography, and tandem mass spectrometry (MS/MS) aimed at comprehensive site-specific glycosylation analysis in protein mixtures. The strategy described herein involves the analysis of a complex mixture of glycopeptides generated from immobilized-Pronase digestion of a cocktail of glycoproteins consisting of bovine lactoferrin, kappa casein, and bovine fetuin using nanoflow liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (nano-LC-Q-TOF MS). The resulting glycopeptides were chromatographically separated on a micro fluidic chip packed with porous graphitized carbon and analyzed via MS and MS/MS analyses. In all, 233 glycopeptides (identified based on composition and including isomers) corresponding to 18 glycosites were observed and determined in a single mixture. The glycopeptides were a mixture of N-linked glycopeptides (containing high mannose, complex and hybrid glycans) and O-linked glycopeptides (mostly sialylated). Results from this study were comprehensive as detailed glycan microheterogeneity information was obtained. This approach presents a platform to simultaneously characterize N- and O-glycosites in the same mixture with extensive site heterogeneity.


Assuntos
Cromatografia Líquida/métodos , Glicopeptídeos/análise , Glicoproteínas/metabolismo , Nitrogênio/metabolismo , Oxigênio/metabolismo , Proteômica/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Caseínas/análise , Bovinos , Glicosilação , Lactoferrina/análise , alfa-Fetoproteínas/análise
9.
Cell Mol Immunol ; 8(3): 248-54, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21278762

RESUMO

Anemia and immunological dysfunction (i.e. immunosenescence) are commonly found in older subjects and nutritional approaches are sought to counteract these phenomena. Spirulina is a filamentous and multicellular bule-green alga capable of reducing inflammation and also manifesting antioxidant effects. We hypothesized that Spirulina may ameliorate anemia and immunosenescence in senior citizens with a history of anemia. We enrolled 40 volunteers of both sexes with an age of 50 years or older who had no history of major chronic diseases. Participants took a Spirulina supplementation for 12 weeks and were administered comprehensive dietary questionnaires to determine their nutritional regimen during the study. Complete cell count (CCC) and indoleamine 2,3-dioxygenase (IDO) enzyme activity, as a sign of immune function, were determined at baseline and weeks 6 and 12 of supplementation. Thirty study participants completed the entire study and the data obtained were analyzed. Over the 12-week study period, there was a steady increase in average values of mean corpuscular hemoglobin in subjects of both sexes. In addition, mean corpuscular volume and mean corpuscular hemoglobin concentration also increased in male participants. Older women appeared to benefit more rapidly from Spirulina supplements. Similarly, the majority of subjects manifested increased IDO activity and white blood cell count at 6 and 12 weeks of Spirulina supplementation. Spirulina may ameliorate anemia and immunosenescence in older subjects. We encourage large human studies to determine whether this safe supplement could prove beneficial in randomized clinical trials.


Assuntos
Anemia/dietoterapia , Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Suplementos Nutricionais , Spirulina , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anemia/diagnóstico , Anemia/imunologia , Hemoglobinas/genética , Hemoglobinas/metabolismo , Humanos , Imunidade/efeitos dos fármacos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Masculino , Pessoa de Meia-Idade , Spirulina/imunologia
10.
Br J Nutr ; 99(2): 287-96, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17761014

RESUMO

Chicory roots are rich in inulin that is degraded into SCFA in the caecum and colon. Whole-body SCFA metabolism was investigated in rats during food deprivation and postprandial states. After 22 h of food deprivation, sixteen rats received an IV injection of radioactive 14C-labelled SCFA. The volume of distribution and the fractional clearance rate of SCFA were 0.25-0.27 litres/kg and 5.4-5.9 %/min, respectively. The half-life in the first extracellular rapidly decaying compartment was between 0.9 and 1.4 min. After 22 h of food deprivation, another seventeen rats received a primed continuous IV infusion of 13C-labelled SCFA for 2 h. Isotope enrichment (13C) of SCFA was determined in peripheral arterial blood by MS. Peripheral acetate, propionate and butyrate turnover rates were 29, 4 and 0.3 micromol/kg per min respectively. Following 4 weeks of treatment with chicory root or control diets, eighteen fed rats received a primed continuous IV infusion of 13C-labelled SCFA for 2 h. Intestinal degradation of dietary chicory lowered caecal pH, enhanced caecal and colonic weights, caecal SCFA concentrations and breath H2. The diet with chicory supplementation enhanced peripheral acetate turnover by 25 % (P = 0.017) concomitant with an increase in plasma acetate concentration. There were no changes in propionate or butyrate turnovers. In conclusion, by setting up a multi-tracer approach to simultaneously assess the turnovers of acetate, propionate and butyrate it was demonstrated that a chronic chicory-rich diet significantly increases peripheral acetate turnover but not that of propionate or butyrate in rats.


Assuntos
Acetatos/sangue , Cichorium intybus , Ácidos Graxos Voláteis/sangue , Animais , Butiratos/sangue , Radioisótopos de Carbono , Ceco/metabolismo , Colo/metabolismo , Ácidos Graxos Voláteis/biossíntese , Feminino , Privação de Alimentos/fisiologia , Meia-Vida , Masculino , Veia Porta/metabolismo , Período Pós-Prandial/fisiologia , Propionatos/sangue , Ratos
11.
Contemp Clin Trials ; 27(4): 364-73, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16632411

RESUMO

BACKGROUND: Detrimental effects of consumption of industrial trans fatty acids (TFA) from partially hydrogenated vegetable oils (PHVO) on cardiovascular disease (CVD) risk factors are well documented. However, very little information is available on the effect of natural sources of TFA coming from milk fat, dairy products and ruminant meat. In fact, due to the naturally low level of TFA in milk fat, it is almost impossible to conduct a clinical trial with a limited number of subjects (<200). METHODOLOGY: To compare the effects of industrial and natural dietary sources of TFA, two specific test fats have been designed and produced. A substantial amount of milk fat (130 kg) enriched in TFA has been produced by modification of the cow's diet and selection of cows with the highest TFA content. The level obtained was approximately 4- to 7-fold higher than typically present in milk fat (approximately 20 instead of 3-6 g/100 g of total fatty acids). The control fat is composed of PHVO balanced in saturated fatty acids (lauric, myristic and palmitic). Both experimental fats contain about 20-22% of monounsaturated TFA and the volunteers' daily experimental fat intake (54 g), will represent about 12.0 g/day of TFA or 5.4% of the daily energy (based on 2000 kcal/day). These two test fats have been incorporated into food items and will be provided to 46 healthy subjects under a randomised, double blind, controlled, cross-over design. The primary outcome is high-density lipoprotein cholesterol (HDL-C), which is an independent risk factor for CVD. Other parameters such as low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), and HDL-C level and subclasses will be also to be evaluated. CONCLUSION: We have shown that it is technically feasible to perform a clinical trial on the comparative effects of natural and industrial sources of TFA isomers on CVD risk factors. Results are expected by mid-2006.


Assuntos
Doenças Cardiovasculares/dietoterapia , Ácidos Graxos trans/uso terapêutico , Adulto , Doenças Cardiovasculares/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Fatores de Risco , Resultado do Tratamento
12.
Br J Nutr ; 94(5): 623-32, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16277761

RESUMO

Nutrigenomics is the study of how constituents of the diet interact with genes, and their products, to alter phenotype and, conversely, how genes and their products metabolise these constituents into nutrients, antinutrients, and bioactive compounds. Results from molecular and genetic epidemiological studies indicate that dietary unbalance can alter gene-nutrient interactions in ways that increase the risk of developing chronic disease. The interplay of human genetic variation and environmental factors will make identifying causative genes and nutrients a formidable, but not intractable, challenge. We provide specific recommendations for how to best meet this challenge and discuss the need for new methodologies and the use of comprehensive analyses of nutrient-genotype interactions involving large and diverse populations. The objective of the present paper is to stimulate discourse and collaboration among nutrigenomic researchers and stakeholders, a process that will lead to an increase in global health and wellness by reducing health disparities in developed and developing countries.


Assuntos
Genômica , Fenômenos Fisiológicos da Nutrição/fisiologia , Animais , Modelos Animais de Doenças , Ingestão de Alimentos , Meio Ambiente , Variação Genética/genética , Genoma Humano , Humanos , Cooperação Internacional , Fenótipo , Pesquisa
13.
Electrophoresis ; 26(19): 3641-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16196105

RESUMO

The nanoLC separations of oligosaccharides using microchip-based columns are described. Mixtures of alditols from mucins and human milk are separated on graphitized carbon. The nanoLC-MS device showed high mass accuracy for the oligosaccharides ranging between 1 and 6 ppm on routine analyses. The high mass accuracy readily allowed identification of oligosaccharide peaks and the determination of their compositions. High retention time reproducibility was exhibited by the microchip LC. Little variation was observed for standard sample either alone or in a complex heterogeneous mixture. The nanoLC-MS exhibits excellent capabilities in profiling mixtures of oligosaccharides.


Assuntos
Cromatografia Líquida/instrumentação , Espectrometria de Massas , Técnicas Analíticas Microfluídicas/instrumentação , Nanotecnologia/instrumentação , Oligossacarídeos/análise , Carbono/química , Humanos , Leite Humano/química , Mucinas/química
14.
Am J Clin Nutr ; 82(3): 497-503, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16155259

RESUMO

Metabolomics has been widely adopted in pharmacology and toxicology but is relatively new in human nutrition. The ultimate goal, to understand the effects of exogenous compounds on human metabolic regulation, is similar in all 3 fields. However, the application of metabolomics to nutritional research will be met with unique challenges. Little is known of the extent to which changes in the nutrient content of the human diet elicit changes in metabolic profiles. Moreover, the metabolomic signal from nutrients absorbed from the diet must compete with the myriad of nonnutrient signals that are absorbed, metabolized, and secreted in both urine and saliva. The large-bowel microflora also produces significant metabolic signals that can contribute to and alter the metabolome of biofluids in human nutrition. Notwithstanding these possible confounding effects, every reason exists to be optimistic about the potential of metabolomics for the assessment of various biofluids in nutrition research. This potential lies both in metabolic profiling through the use of pattern-recognition statistics on assigned and unassigned metabolite signals and in the collection of comprehensive data sets of identified metabolites; both objectives have the potential to distinguish between different dietary treatments, which would not have been targeted with conventional techniques. The latter objective sets out a well-recognized challenge to modern biology: the development of libraries of small molecules to aid in metabolite identification. The purpose of the present review was to highlight some early challenges that need to be addressed if metabolomics is to realize its great potential in human nutrition.


Assuntos
Genômica/métodos , Metabolismo/fisiologia , Fenômenos Fisiológicos da Nutrição , Dieta , Meio Ambiente , Regulação da Expressão Gênica , Genótipo , Nível de Saúde , Humanos , Metabolismo/efeitos dos fármacos , Metabolismo/genética
16.
Metabolism ; 53(2): 236-40, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14767877

RESUMO

There is growing evidence supporting the importance of inflammation in all stages of atherosclerosis. While both omega-3 polyunsaturated fatty acids (n3PUFA) and the lipid-soluble antioxidant alpha-tocopherol (AT) have been shown to independently have significant anti-inflammatory effects, there is paucity of data examining the effect of n3PUFA alone and in combination with AT on markers of inflammation and monocyte function. Therefore, we tested the effect of n3PUFA alone, all-rac (synthetic) AT alone, and the combination on markers of inflammation and monocyte function. Healthy nonsmoking volunteers were randomly assigned to 1 of 4 groups (n = 20 per group): 1.5 g/d n3PUFA, 800 IU/d AT, 1.5 g n3PUFA + 800 IU/d AT, or placebo in a parallel double-blinded study. Compared to baseline, 12 weeks of supplementation resulted in no changes in plasma lipids regardless of treatment. Plasma AT was significantly increased only in those groups that received AT (P <.0001). Similarly, groups receiving n3PUFA showed a significant increase in plasma docosahexaenoic acid (P <.0001). No significant within- or between-group differences were found for plasma levels of high-sensitivity C-reactive protein (hsCRP). Furthermore, there were no differences in monocyte proinflammatory cytokine release (interleukin [IL]-1beta, tumor necrosis factor [TNF]-alpha and IL-6) after activation with monocyte chemotactic protein-1 (MCP-1). In conclusion, supplementation with n3PUFA and all-rac AT at these doses is not anti-inflammatory.


Assuntos
Anti-Inflamatórios , Ácidos Graxos Ômega-3/farmacologia , Vitamina E/farmacologia , Adulto , Biomarcadores , Proteína C-Reativa/metabolismo , Quimiocina CCL2/metabolismo , Citocinas/metabolismo , Suplementos Nutricionais , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Estereoisomerismo , Vitamina E/sangue
17.
Ann N Y Acad Sci ; 1029: 374-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15681785

RESUMO

Ibuprofen and antibiotics are commonly prescribed during early childhood. When given to mice at the time at which oral tolerance is induced, both treatments affect either the induction or the maintenance of oral tolerance. These results suggest that the coadministration of these and similarly acting drugs should be considered cautiously for infants at risk of allergy.


Assuntos
Antibacterianos/farmacologia , Ibuprofeno/farmacologia , Tolerância Imunológica/imunologia , Animais , Pré-Escolar , Dinoprostona/metabolismo , Fezes/microbiologia , Humanos , Tolerância Imunológica/efeitos dos fármacos , Imunoglobulina E/sangue , Camundongos , Camundongos Endogâmicos BALB C
18.
Eur J Nutr ; 42(3): 171-9, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12811475

RESUMO

BACKGROUND: Conjugated linoleic acid (CLA) has been reported to decrease fat deposition, and increase lean body mass. This has been broadly inferred to mean that CLA alters protein turnover. However, data to test the effects of CLA on protein turnover are lacking. An enhancement in immune responses by CLA has also been demonstrated. AIM OF THE STUDY: The objective of this study was to determine the potential for dietary CLA and protein intervention to improve nutritional and functional recovery in an animal model of catabolic stress and immunodepletion. METHODS: Diets varying in their protein levels in the presence or absence of CLA were tested for their effects on the recovery of glucocorticoid (intraperitoneal injection of dexamethasone, 120 mg/kg) treated rats. Following steroid injection, rats were fed 4 dietary treatments for 4 d. The diets contained 10 or 20 g/100 g protein with or without 0.5 g/100 g CLA. RESULTS: Dexamethasone treatment resulted in a decreased food intake and loss of weight, independent of dietary treatment. A higher number of blood monocytes occurred in rats fed the high CLA diets. The protein fractional synthesis rate in spleens of rats fed the diets containing either high proteins or CLA were higher compared to those fed diets with low protein content or without CLA, respectively. CLA, consumed post-dexamethasone treatment, did not improve protein turnover in the other tissues studied, including gut mucosa, liver, muscle and thymus. CONCLUSIONS: The present study was performed to determine the effect of CLA in acute conditions, as opposed to a preventive approach, on the recovery from a catabolic stress with immunodepletion. Overall, no effect of short-term feeding CLA on the recovery from dexamethasone-mediated immunodepletion was observed.


Assuntos
Dexametasona/farmacologia , Proteínas Alimentares/administração & dosagem , Glucocorticoides/farmacologia , Imunidade Celular/efeitos dos fármacos , Ácidos Linoleicos/administração & dosagem , Animais , Contagem de Células Sanguíneas , Proteínas Alimentares/metabolismo , Suplementos Nutricionais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glutationa/análise , Injeções Intraperitoneais/veterinária , Ácidos Linoleicos/farmacologia , Fígado/química , Fígado/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Músculo Esquelético/química , Músculo Esquelético/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Timo/efeitos dos fármacos
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