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The involvement of the CD40-CD40L pathway in activated platelet-induced changes in HUVEC COX-2 and PPARα expression

Yan-qing Wu1, Xiao-shu Chen, Jun-bing Chai

  • 1Department of Cardiovasology, The Second Affiliated Hospital, Nan Chang University, 1st, Ming-De road, Nanchang, Jiang Xi Province 330006, China. wuyqyq@163.com

Inflammation
|January 6, 2012
PubMed

We aim to determine the extent of the CD40-CD40L pathway involvement in activated platelet-induced changes in human umbilical endothelial cells (HUVECs). Activated platelets were co-incubated with HUVECs in the presence or absence of CD40LmAb. HUVECs were also directly stimulated with rhCD40L. HUVEC endothelial cyclooxygenase 2 (COX-2) and peroxisome proliferator-activated receptor alpha (PPARα) expression was then assessed. To estimate COX-2 activity, PGE2 concentration was determined. PPARα activity was assessed using a nuclear factor activity kit. Co-incubation with activated platelets increased HUVEC COX-2 and PPARα mRNA expression (P < 0.01). The addition of CD40L mAb significantly attenuated these increases in mRNA and protein (both P < 0.01). Direct stimulation by rhCD40L increased HUVEC COX-2 mRNA and protein (P < 0.05) but did not significantly change the expression of PPARα mRNA and protein. CD40LmAb significantly decreased (P < 0.05) and rhCD40L significantly (P < 0.01) increased COX-2 enzymatic activity, but had almost no effects on PPARα binding activity. Activated platelets may increase HUVEC COX-2 expression and activity partly through the CD40-CD40L pathway.

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