Format

Send to

Choose Destination
Biochim Biophys Acta. 1996 Nov 22;1304(2):139-44.

Effect of vitamin E on expression of cyclooxygenase-2 in lipopolysaccharide-stimulated rat macrophages.

Author information

1
Department of Biochemistry, School of Dentistry, Sapporo, Japan.

Abstract

To clarify the role of vitamin E (alpha-tocopherol) for the induction of cyclooxygenase-2 (COX-2) in rat macrophages stimulated by lipopolysaccharide (LPS), vitamin E-enriched macrophages were prepared by intraperitoneal injection of vitamin E for 6 days at a rate of 5 mg per day. The production of PGE2 was increased in dose- and time-dependent manners by addition of LPS in both control and vitamin E-enriched peritoneal macrophages. The maximum effect of LPS was observed in 12 h at concentration of 5 micrograms/ml. By analyzing COX-2 mRNA level by Northern blot and COX-2 enzyme mass and phosphotyrosine by Western blot, it was revealed that the increase of PGE2 production reflected the induction of COX-2 expression through activation of tyrosine kinase. Vitamin E failed to inhibit PGE2 production in LPS-stimulated macrophages; however, genistein, a tyrosine kinase inhibitor, completely inhibited the production at 100 microM. These results suggest that vitamin E does not inhibit COX-2 expression via LPS-mediated tyrosine kinase signal transduction pathway.

PMID:
8954137
DOI:
10.1016/s0005-2760(96)00114-2
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center