HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

The beta-specific protein kinase C inhibitor ruboxistaurin (LY333531) suppresses glucose-induced adhesion of human monocytes to endothelial cells in vitro.

AbstractAIMS:
Strong evidence shows that late diabetic complications in diabetes mellitus are substantially related to an increased synthesis of diacylglycerol with a subsequent activation of protein kinase C (PKC) beta. Several studies have shown that specific inhibition of the PKC isoform beta by ruboxistaurin is able to attenuate the development of microvascular complications under diabetic conditions. The aim of this in vitro study was to investigate the effect of ruboxistaurin on glucose-induced adhesion of monocytes to endothelial cells, representing one of the first pivotal steps in the course of atherogenesis.
METHODS:
Human umbilical venous endothelial cells were isolated and cultured to confluence in microtiter plates. After coincubation with monocytes in the presence of 0, 10, or 400 ng ruboxistaurin to achieve PKC beta-specific and -unspecific PKC inhibition, cells were fixed and monocyte adhesion was determined by means of a standardized chemiluminescence assay. Expression of adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin) was also measured by chemiluminescence methods.
RESULTS:
Adhesion of monocytes to endothelial cells cultured under hyperglycemic conditions (27.7 mM glucose) was increased by 30.9 +/- 5.1% (p < 0.001) versus endothelial cells cultured under normoglycemic (NG) conditions (5.5 mM). Pretreatment of endothelial cells with 10 nM (PKC beta-specific concentration) and 400 nM (PKC beta-unspecific concentration) led to a significant reduction of glucose-induced adhesion of monocytes to endothelial cells that was statistically not different from endothelial adhesion under NG conditions (-7.2 +/- 3.1 and -8.1 +/- 2.6%, respectively; not significant vs NG). A nonsignificant tendency to lower the expression of adhesion molecules was seen with 10 ng of ruboxistaurin.
CONCLUSIONS:
We conclude that monocyte adhesion to endothelial cells under hyperglycemic conditions is at least mediated by PKC beta activation. Ruboxistaurin is able to suppress this monocyte adhesion even in a PKC beta-specific concentration. Further studies should evaluate these potential effects of ruboxistaurin in vivo.
AuthorsThomas Kunt, Thomas Forst, Christof Kazda, Oliver Harzer, Martin Engelbach, Mirjam Löbig, Jürgen Beyer, Andreas Pfützner
JournalJournal of diabetes science and technology (J Diabetes Sci Technol) Vol. 1 Issue 6 Pg. 929-35 (Nov 2007) ISSN: 1932-2968 [Electronic] United States
PMID19885168 (Publication Type: Journal Article)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: