28 research outputs found
Multidirectional Time-Dependent Effect of Sinigrin and Allyl Isothiocyanate on Metabolic Parameters in Rats
Sinigrin (SIN) and allyl isothiocyanate (AITC) are compounds found in high concentrations in Brassica family vegetables, especially in Brussels sprouts. Recently, they have been used as a nutrition supplement for their preventive and medicinal effect on some types of cancer and other diseases. In this research, nutritional significance of parent glucosinolate sinigrin 50 μmol/kg b. w./day and its degradation product allyl isothiocyanate 25 μmol/kg b. w./day and 50 μmol/kg b. w./day was studied by the evaluation of their influence on some parameters of carbohydrate and lipid metabolism in an animal rat model in vivo after their single (4 h) and 2 weeks oral administration. Additionally, the aim of this trial was to evaluate the direct action of AITC on basal and epinephrine-induced lipolysis in isolated rat adipocytes at concentration 1 μM, 10 μM and 100 μM in vitro. Sole AITC after 4 h of its ingestion caused liver triacylglycerols increment at both doses and glycaemia only at the higher dose. Multiple SIN treatment showed its putative bioconversion into AITC. It was found that SIN and AITC multiple administration in the same way strongly disturbed lipid and carbohydrate homeostasis, increasing esterified and total cholesterol, free fatty acids and lowering tracylglycerols in the blood serum. Additionally, AITC at both doses elevated insulinaemia and liver glycogen enhancement. The in vitro experiment revealed that AITC potentiated basal lipolysis process at 10 μM, and had stimulatory effect on epinephrine action at 1 μM and 10 μM. The results of this study demonstrated that the effect of SIN and AITC is multidirectional, indicating its impact on many organs like liver as well as pancreas, intestine in vivo action and rat adipocytes in vitro. Whilst consumption of cruciferous vegetables at levels currently considered “normal” seems to be beneficial to human health, this data suggest that any large increase in intake could conceivably lead to undesirable effect. This effect is potentiated with time of action of the examined compounds, whose influence is rather adverse for the majority of metabolic pathways (liver steatosis at short duration and insulinaemia, cholesterolaemia at long time treatment). Beneficial action of AITC concerned intensified hydrolysis of TG in the blood serum with a simultaneous lipolysis in adipocytes
Intestinal acyl-CoA:diacylglycerol acyltransferase 2 overexpression enhances postprandial triglyceridemic response and exacerbates high fat diet-induced hepatic triacylglycerol storage
Intestinal acyl-CoA:diacylglycerol acyltransferase 2 (DGAT2) is important in the cellular and physiological responses to dietary fat. To determine the effect of increased intestinal DGAT2 on cellular and physiological responses to acute and chronic dietary fat challenges, we generated mice with intestine-specific overexpression of DGAT2 and compared them with intestine-specific overexpression of DGAT1 and wild-type (WT) mice. We found that when intestinal DGAT2 is present in excess, triacylglycerol (TG) secretion from enterocytes is enhanced compared to WT mice; however, TG storage within enterocytes is similar compared to WT mice. We found that when intestinal DGAT2 is present in excess, mRNA levels of genes involved in fatty acid oxidation were reduced. This result suggests that reduced fatty acid oxidation may contribute to increased TG secretion by overexpression of DGAT2 in intestine. Furthermore, this enhanced supply of TG for secretion in Dgat2(Int) mice may be a significant contributing factor to the elevated fasting plasma TG and exacerbated hepatic TG storage in response to a chronic HFD. These results highlight that altering fatty acid and TG metabolism within enterocytes has the capacity to alter systemic delivery of dietary fat and may serve as an effective target for preventing and treating metabolic diseases such as hepatic steatosis. (C) 2013 Elsevier B.V. All rights reserved
A produção acadêmica publicada na revista Gestão & Produção de 1999 a 2010: tendências e direções para pesquisas futuras Academic research published in the Management & Production Journal (G&P, 1999-2010): trends and future research directions
Esta pesquisa analisou as publicações da revista Gestão & Produção (G&P) nos últimos doze anos. O objetivo foi identificar as tendências de pesquisa na área "Gestão da Produção e Operações" (POM): sua diversidade em termos de quantidade, tópico de interesse, fonte de dados, contribuição da pesquisa e redes sociais. Os artigos da revista G&P foram classificados quanto ao tipo de contribuição primária (conceitual, aplicação da teoria e construção de teoria), abordagem de coleta de dados (questionário, estudo de caso, pesquisa qualitativa, pesquisa de arquivo, pesquisa de laboratório), técnica de análise de dados (estatística básica, técnicas de análise multivariada e modelagem matemática) e tópico de interesse (estratégia de operações, qualidade, gestão da cadeia de suprimento, entre outros). Com o levantamento realizado, observa-se que a pesquisa em gestão de operações cresceu consideravelmente na última década. O foco dos artigos amadureceu, passou de uma ênfase de artigos descritivos para uma vertente mais voltada à aplicação de teoria. A principal das fontes foram casos. Sugestões de direções para pesquisas futuras foram propostas.<br>This study is a review and evaluation of studies published in a Brazilian journal of management & production (G&P) from 1999 to 2010 in order to investigate the diversity of articles in terms of the purposes of research, data collection approaches, and data analysis techniques. The research articles were classified based on their primary purpose (theory building, application, and concepts), data collection approach (case study, qualitative research, archival research, survey-based research, laboratory research, and field research), data analysis technique (descriptive statistics, various multivariate statistical techniques, and mathematical modeling), and operations topics (strategy, quality, and supply chain management). The numbers of articles published increased substantially between 1999 to 2010. The focus of the articles on the manufacturing industry published in this journal changed considerably, and more recently the gap between the number of manufacturing and service-focused articles on production and operations management (POM) has reduced. While previous articles published in the G&P journal were based on conceptual descriptions, our results indicate that the journal has published articles based on theory and application. Case study is the most widely used method for data collection. Directions for future research in operations management were also discussed