Proanthocyanidins, from <it>Ribes nigrum</it> leaves, reduce endothelial adhesion molecules ICAM-1 and VCAM-1

• Main Authors: Desmecht D (Author), Nusgens B (Author), Kinet M (Author), Garbacki N (Author), Damas J (Author)
• Format: Book
• Published: BMC, 2005-08-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.1186/1476-9255-2-9; 1476-9255
• Keywords: Therapeutics. Pharmacology; RM1-950
• Source: Journal of Inflammation, Vol 2, Iss 1, p 9 (2005)

<p>Abstract</p> <p>Background</p> <p>The effects of proanthocyanidins (PACs), isolated from blackcurrant (<it>Ribes nigrum </it>L.) leaves, on neutrophil accumulation during inflammatory processes were investigated <it>in vivo </it>and <it>in vitro</it>.</p> <p>Methods</p> <p><it>In vivo </it>studies were performed using carrageenin-induced pleurisy in rats pre-treated with PACs. Exudate volume and PMNs accumulation were measured. Leukocyte cell adhesion molecules (LFA-1, Mac-1 and VLA-4) mobilization in circulating granulocytes were analysed by flow cytometry and endothelial cell adhesion molecules (ICAM-1 and VCAM-1) were detected by immunohistochemistry on lung sections.</p> <p><it>In vitro </it>studies were conducted on endothelial LT2 cells, stimulated with TNF-α, to evaluate ICAM-1, IL-8 and VEGF mRNA expression upon PACs treatment.</p> <p>Data sets were examined by one-way analysis of variance (ANOVA) followed by a Scheffe post-hoc test.</p> <p>Results</p> <p>Pretreatment of the animals with PACs (10, 30 and 60 mg/kg) inhibited dose-dependently carrageenin-induced pleurisy in rats by reducing pleural exudate formation and PMNs infliltration. Leukocyte cell adhesion molecules mobilization was not down-regulated on granulocytes by PACs. Immunohistochemistry on lung sections showed a decreased production of endothelial cell adhesion molecules.</p> <p><it>In vitro </it>experiments demonstrated that PACs were able to significantly inhibit ICAM-1 but not IL-8 and VEGF₁₆₅mRNA expression. Moreover, VEGF₁₂₁mRNA expression was dose-dependently enhanced.</p> <p>Conclusion</p> <p>This study provides evidence to support the anti-inflammatory activity of proanthocyanidins is related to an inhibition of leukocyte infiltration which can be explained at least in part by a down-regulation of endothelial adhesion molecules, ICAM-1 and VCAM-1 and that these compounds are capable of modulating TNF-α-induced VEGF transcription.</p>