IMIBIO-SL   20937
INSTITUTO MULTIDISCIPLINARIO DE INVESTIGACIONES BIOLOGICAS DE SAN LUIS
Unidad Ejecutora - UE
artículos
Título:
Vitamin A deficiency injures liver parenchyma and alters the expression of hepatic extracellular matrix.
Autor/es:
AGUILAR RP; GENTA S; OLIVEROS L; ANZULOVICH A; GIMÉNEZ MS; SÁNCHEZ SS
Revista:
JOURNAL OF APPLIED TOXICOLOGY
Editorial:
John Wiley & Sons, Ltd
Referencias:
Año: 2009 vol. 29 p. 214 - 222
ISSN:
0260-437X
Resumen:
Vitamin A is an essential lipid-soluble nutrient that is crucial for morphogenesis and adult tissue maintenance. The retinoid homeostasis in the liver depends on a regular supply of vitamin A from an adequate dietary intake to preserve the normal organ structure and functions. This study focuses on the effect of vitamin A deficiency on the morphology and extracellular proteins expression of the liver in adult Wistar rats. Animals were fed with a normal (control group) or deficient vitamin A diet for 3 months. At the end of the experimental period, histological examination of the livers under light and electron microscopy revealed that vitamin A deficiency produced a loss of hepatocyte cord disposition with an irregular parenchymal organization. Abundant fat droplets were present in the cytoplasm of the hepatocytes. Elongated myofibroblastic-like cells with an irregular cytoplasmic process and without lipid droplets could be seen at the perisinusoidal space, where an elevated intensity of alpha smooth muscle actin (a-SMA) was observed. These results suggest that an activation of hepatic stellate cells (HSCs) occurred. Moreover, immunochemical methods revealed that vitamin A deficiency led to an increased expression of hepatic fibronectin, laminin and collagen type IV. We propose that vitamin A deprivation caused liver injury and that HSCs underwent a process of activation in which they produced a-SMA and synthesized extracellular components. These changes may be a factor predisposing to liver fibrosis. In consequence, vitamin A deprivation could affect human and animal health. Copyright © 2008 John Wiley & Sons, Ltd.