HDL is the major source of vitamin E for type II pneumocytes.
Free Radic Biol Med
; 27(7-8): 882-90, 1999 Oct.
Article
en En
| MEDLINE
| ID: mdl-10515593
The alveolar surfactant is a prime target of reactive oxygen species present in air. Alveolar surfactant is supplemented with vitamin E during its assembly in type II pneumocytes. However, it is unknown which of the lipoproteins supply type II pneumocytes with vitamin E. The measurement of the uptake kinetics indicates that HDL might be the primary source of the vitamin E uptake by type II pneumocytes. Vitamin E depletion of rats caused an increase of vitamin E uptake by isolated type II pneumocytes from HDL but not from LDL or VLDL. We demonstrated that type II pneumocytes express the scavenger receptor class B type 1 (SR-B1), an HDL-specific receptor. Vitamin E depletion caused an increased expression of SR-B1 by a post-transcriptional mechanism. The increased vitamin E uptake from HDL and the increased expression of the SR-B1 were reversed by refeeding the vitamin. We propose that HDL is the primary source of vitamin E for type II pneumocytes. The rate of uptake of vitamin E by this cell type might be regulated by the expression of SR-B1.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Vitamina E
/
Receptores Inmunológicos
/
Receptores de Lipoproteína
/
Lipoproteínas HDL
/
Proteínas de la Membrana
Límite:
Animals
Idioma:
En
Revista:
Free Radic Biol Med
Asunto de la revista:
BIOQUIMICA
/
MEDICINA
Año:
1999
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Estados Unidos