Effect of cis-resveratrol on genes involved in nuclear factor kappa B signaling.

This study investigated for the first time the effects of the cis isomer of RESV (c-RESV), a polyphenol present in red wine, on an array of genes whose expression is controlled by nuclear factor kappa B (NF-kappaB) and whose transcriptional activation is critical in a number of pathologies (including some cardiovascular diseases). In inflammatory peritoneal macrophages stimulated with lipopolysaccharide (LPS) and gamma interferon (IFN-gamma), c-RESV significantly blocked the expression of genes related to the REL/NF-kappaB/IkappaB family, adhesion molecules and acute-phase proteins; however, the greatest modulatory effect was obtained on the expression of genes related to the pro-inflammatory cytokines. c-RESV down-regulated the nuclear factor of kappa light chain gene enhancer in B-cells 1 (NFkappaBL1) gene product p105 and up-regulated the nuclear factor of kappa light chain gene enhancer in B-cells inhibitor alpha (IkappaBalpha) gene. c-RESV also significantly inhibited intercellular adhesion molecule-1 (ICAM-1) gene expression and the transmembrane receptors RIP (receptor TNFRSF) and TLR3 (toll-like receptor 7). At 100 muM, c-RESV significantly inhibited transcription of Scya2 (chemokine MCP-1), the chemokine RANTES (regulated on activation, normal T cell expressed and secreted), pro-inflammatory cytokines that attract monocyte-granulocyte cells such as M-CSF (colony-stimulating factor 1), GM-CSF (colony-stimulating factor 2) and G-CSF (colony-stimulating factor 3), the cytokine tumor growth factor beta (TGF-beta) and the extracellular ligand IL-1alpha. In contrast, c-RESV stimulated transcription of the pro-inflammatory cytokines IL-6 and tumor necrosis factor alpha (TNF-alpha), the extracellular ligand IL-1beta, and the IFN regulatory factor (IRF)-1. In conclusion, c-RESV has a significant modulatory effect on the NF-kappaB signaling pathway and, consequently, an important antioxidant role that may partially explain the cardioprotective effects attributed to long-term moderate red wine consumption.

Calpain controls the balance between protein tyrosine kinase and tyrosine phosphatase activities during platelet activation.

Protein phosphorylation was studied during platelet stimulation in two ranges of ionized [Ca2+]. At ionized [Ca2+]i< or = 1 microM, proteins were phosphorylated. At ionized [Ca2+]i > or = 4 microM, phosphoproteins disappeared. Protein dephosphorylation was prevented by the combined action of calpeptin and phosphatase inhibitors. Protein tyrosine phosphatase activity was stimulated regardless of the ionized [Ca2+] level. Protein tyrosine kinase activity was stimulated at ionized [Ca2+]i < or =1 microM, whereas at ionized [Ca2+]i > or =4 microM, no protein tyrosine kinase activity was observed except in the presence of calpeptin. Thus, the massive tyrosine phosphoprotein disappearance observed at a high ionized [Ca2+]i resulted not only in protein tyrosine phosphatase activation, but also in calpain-induced protein tyrosine kinase inactivation.

Pyridazines. XVIII. 6-Aryl-3(2H)-pyridazinones inhibit calcium influx in stimulated platelets.

6-Phenyl-5-hydroxymethyl-4,5-dihydro-3(2H)-pyridazinone (1) and 6-thienyl-5-hydroxymethyl-4,5-dihydro-3(2H)-pyridazinone (2) inhibit platelet aggregation induced by thrombin (IC50 = 0.25 and 0.26 mM, respectively) or by the calcium ionophore ionomycin (IC50 = 0.42 and 0.43 mM, respectively). Pyridazinones 1 and 2 also show concentration-dependent attenuation of the increases in platelet cytosolic free calcium concentration induced by thrombin and ionomycin, suggesting that their antiaggregatory activity may be due to their capacity to inhibit the passage of calcium through the cytoplasmic membrane. This effect may be implicated in other pharmacological activities of 6-aryl-5-substituted-pyridazinones.