El tejido adiposo: algo más que un reservorio de energía

Grasas y Aceites (Impact Factor: 0.74). 01/2009; DOI: 10.3989/gya.043209
Source: DOAJ

ABSTRACT Adipose tissue is a reservoir of energy and also an organ that contributes to the aesthetics and health of human body working as an endocrine tissue. White adipose tissue, which is formed by unilocular adipose cells, can modify organic homeostasis by controlling energy expenditure and consumption and by producing adipokines that regulate food consumption, and carbohydrate and lipid metabolic utilization. Brown adipose tissue is structured by multilocular cells containing many small fat drops that can be easily hydrolyzed. This tissue is involved in adaptative or facultative thermogenesis because it contains the uncoupling-1 protein (UCP-1) which by inhibiting ATP synthesis releases heat. The size of brow adipose tissue is reduced with aging and the most recent future strategies to fight obesity may be by transforming white cells into brown adipose tissue. The present work reviews the main structural and functional characteristics of white and brown adipose tissue with emphasis in its endocrine and regulatory function.

El tejido adiposo es un reservorio de grasa y también un órgano que contribuye a la estética y a la salud de las personas, tarea que cumple funcionando como un tejido endocrino. El tejido adiposo blanco, formado por células adiposas uniloculares puede regular la homeostasis orgánica entre el gasto y el consumo de energía. Produce una serie de adipokinas que regulan el consumo de alimentos, la utilización de glucosa y de lípidos por parte del organismo. El tejido adiposo pardo o marrón, estructurado por células multiloculares, contiene numerosas gotas de grasa de pequeño tamaño, las que pueden ser hidrolizadas con mayor facilidad. El tejido participa en la termogénesis adaptativa o facultativa debido a la proteína desacoplante-1 (UCP-1) que inhibe la síntesis de ATP produciendo calor. Con la edad, este tejido se reduce y por ello actualmente se considera que una forma de combatir la obesidad es lograr que el tejido adiposo blanco adquiera característica de pardo. Este trabajo revisa las principales características estructurales y funcionales del tejido adiposo blanco y pardo, con énfasis en sus funciones reguladoras y endocrinas.

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