Abstract

AIM:

To investigate the role of protein kinase C (PKC) to regulate the expression of beta-1, 4-galactosyltransferase-I(beta-1, 4-GalT-I)and the influence to cytoskeleton and adherence ability of human umbilical vein endothelial cells(HUVECs) when stimulated by tumor necrosis factor (TNF-alpha).

METHODS:

Cultured HUVECs were pretreated by various PKC inhibitors or PMA, an excitomotor of PKC respectively for 30 minutes, then stimulated by TNF-alpha for 4 hours, beta-1, 4-GalT-I expression were detected by RT-PCR and Western blot, expression of beta-1, 4-galactosylated carbohydrate chains and cytoskeleton were assayed by immunofluorescence, adherence ability of HUVECs was observed by endothelial-monocyte cell adherence test.

RESULTS:

Up-regulated expression of beta-1, 4-GalT-I and beta-1, 4-galactosylated carbohydrate chains in HUVECs stimulated by TNF-alpha were suppressed by PKC inhibitors and increased by PMA. F-actin and beta-1, 4-GalT-I were partly co-localized in HUVECs, PKC inhibitor inhibited the effect of TNF-alpha on the distribution of f-actin and beta-1, 4-GalT-I. Adherence ability of HUVECs enhanced by LPS was significantly suppressed by PKC inhibitor.

CONCLUSION:

PKC signal transduction pathway may participate in regulating beta-1, 4-GalT-I expression in endothelial cells (EC) stimulated by TNF-alpha, furthermore, polytypes of PKC may participate in this regulating process; PKC might regulate cytoskeleton reorganization and adherence ability of EC through beta-1, 4-GalT-I during inflammation.