Transgenesis of Drosophila melanogaster with an Elovl5 gene enables the production of longer-chain fatty acids / 生物工程学报

In most insects, polyunsaturated fatty acids (PUFAs) are mainly polyunsaturated fatty acids with a carbon-chain length less than 18 carbon atoms, hardly any long-chain polyunsaturated fatty acids such as C20 and C22 that are more valuable and bioactive. This study, by using Drosophila melanogaster (Fruit fly) as a model organism, optimized the Δ6-fatty acid elongase enzyme Elovl5 gene from mice and transferred it to fruit flies for expression. Vectors containing Elovl5 gene were successfully injected into drosophila embryo through the microscopic injection. There were enhanced green fluorescent proteins expressed in the whole developmental stage of Drosophila be means of fluorescence microscope. At the same time, expression of Elovl5 gene significantly contributed to the transformation of fruit flies C18-polyunsaturated fatty acids in the body towards the biosynthesis of longer-chain polyunsaturated fatty acids. The transgenic fruit fly model rich in long-chain polyunsaturated fatty acids such as C20 and C22 were obtained, providing a basis for further research on biosynthesis of polyunsaturated fatty acids in fruit flies.

Composición de ácidos grasos (MUFA y CLA) en tejido muscular de bovino relacionado con la presencia del polimorfismo g.878TC en el gen SCD / Fatty acid composition (MUFA and CLA) in bovine muscle tissue related with the presence of the g.878TC SCD gene polymorphism

El tejido muscular de muchos animales domésticos es fuente de proteínas, grasa y minerales para los seres humanos y está compuesto por una serie de estructuras que le otorgan propiedades nutricionales y bioquímicas. En los ultimos años se ha identificado un polimorfismo de único nucleótido (SNP) en el gen SCD (g.878TC), que influye sobre la composición de ácidos grasos en los bovinos. El objetivo de este estudio fue determinar la presencia del SNP g.878TC en músculo Longissimus dorsi de bovino (Bos taurus) por medio de la técnica PCR-RFLP. Fue utilizada una muestra de 100 novillos de raza Aberdeen Angus criados y sacrificados en la Región de La Araucanía (Chile). La frecuencia genotípica del polimorfismo fue de: 0,33 para TT, 0,43 para TC y 0,24 para el genotipo CC. La frecuencia alélica fue de 0,54 para el alelo T y 0,63 para el alelo C. De acuerdo a la composición de ácidos grasos, se determinó que existe una relación positiva entre el genotipo CC y el contenido de ácidos grasos MUFA y CLA presentes en el músculo Longissimus dorsi de novillos Angus. Por lo tanto, el SNP g.878TC podría ser considerado como un marcador genético para la selección de animales Aberdeen Angus, con una composición de ácidos grasos más saludable...

The muscle tissue of many domestic animals is a source of protein, fat and minerals to humans and consists of a series of structures that give nutritional and biochemical properties. In recent years it has identified a single nucleotide polymorphism (SNP) in the SCD gene (g.878TC), which influences the fatty acid composition in cattle. The aim of this study was to determine the presence of SNP g.878TC in Longissimus dorsi bovine (Bos taurus) using the PCR-RFLP. It was used a sample of 100 Aberdeen Angus steers raised and slaughtered in the region of Araucania (Chile). Polymorphism genotype frequency were: 0.33 for TT, 043 for CT and 0.24 for the CC genotype. The allelic frequency was 0.54 for the T allele and 0.63 for allele C. According to the fatty acid composition was determined that a positive relationship between genotype CC and the content of MUFA and CLA fatty acids present in the Longissimus dorsi muscle of Angus steers. Therefore, the SNP g.878TC could be considered as a genetic marker for selection of animals Aberdeen Angus, with a fatty acid composition more healthy...

High glucose, unsaturated and saturated fatty acids differentially regulate expression of ATP-binding cassette transporters ABCA1 and ABCG1 in human macrophages

The ATP-binding cassette transporters ABCA1 and ABCG1 are highly expressed in macrophage-derived foam cells and promote reverse cholesterol efflux via biogenesis of high-density lipoproteins. The aim of this study was to analyze the direct effects of bioactive factors related to the metabolic syndrome on macrophage transcript levels of all 47 human ABC transporters. Using in vitro M-CSF predifferentiated macrophages and TaqMan low density arrays we could show that linoleic acid, palmitic acid, and high glucose levels have a major impact on ABCA1 and ABCG1 expression but do not strongly affect most other human ABC transporters. In Western blot experiments we demonstrate that ABCA1 and ABCG1 protein levels are synchronously suppressed by high glucose levels and the omega6-unsaturated fatty acid linoleic acid. We conclude that metabolites associated with the metabolic syndrome enhance the formation of atherosclerotic lesions by diminishing the reverse cholesterol transport function of ABCA1 and ABCG1.

Mecanismos moleculares por los cuales los ácidos grasos podrían influir en la captación de glucosa / Molecular mechanism by which free fatty acids migth interfere with periferic insuline action

Esta revisión tiene el propósito de actualizar el probable mecanismo molecular que ejercen los ácidos grasos en las células que captan glucosa, bajo el estimulo de la insulina y su posible implicación en la diabetes mellitus tipo 2 en la que suelen asociarse resistencia a la insulina, obesidad y síndrome metabólico. Entre los mecanismos moleculares por los cuales un aumento de los ácidos grasos libres podría producir resistencia a la insulina, se encuentra la disminución de los niveles de xilulosa 5-fosfato que bloquea la glucólisis por inhibición de la fosfofructocinasa, ello conduce a un aumento de los productos finales en la vía de las hexosaminas y a la activación de la proteincinasa C, un conocido activador de inhibidor de la cinasa Kappa Beta que inhibe la fosforilación del receptor del sustrato de insulina en tirosina, bloqueando los transportadores de glucosa. Existen investigaciones que sugieren que los ácidos grasos libres están implicados en la insulino-resistencia pero el mecanismo bioquímico no esta dilucidado del todo, pues no hay un mecanismo integral que los relacione o interconecte para concluir determinantemente cómo los altos niveles de ácidos grasos libres inducen la resistencia a la insulina

Avances en la genética molecular de la obesidad / Advances in the molecular genetics of the obesity

In the last decade, specially after the discovery of leptin, several neuropeptides that regulate energy intake and expenditure have been described in animal models. This has partially unvelied the underlying mechanisms that regulate body composition and weight and therefore a promise of a more effective treatment of obesity and its comorbidities is ad portas