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Objective-Epidemiology suggests that Mediterranean diets are associated with reduced risk of cardiovascular disease.Because monocyte adhesion to the endothelium is crucial in early atherogenesis, we evaluated whether typical olive oil and red wine polyphenols affect endothelial-leukocyte adhesion molecule expression and monocyte adhesion. Methods and Results-Phytochemicals in olive oil and red wine, including oleuropein, hydroxytyrosol, tyrosol, elenolic acid, and resveratrol, with or without antioxidant activity, were incubated with human umbilical vein endothelial cells for 30 minutes, followed by co-incubation with bacterial lipopolysaccharide or cytokines to trigger adhesion molecule expression. At nutritionally relevant concentrations, only oleuropein, hydroxytyrosol, and resveratrol, possessing a marked antioxidant activity, reduced monocytoid cell adhesion to stimulated endothelium, as well as vascular cell adhesion molecule-1 (VCAM-1) mRNA and protein by Northern analysis and cell surface enzyme immunoassay. Reporter gene assays with deletional VCAM-1 promoter constructs indicated the relevance of nuclear factor-B, activator protein-1, and possibly GATA binding sites in mediating VCAM-1 transcriptional inhibition. The involvement of nuclear factor-B and activator protein-1 was finally demonstrated at electrophoretic mobility shift assays. Conclusions-Olive

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We report the molecular and functional characterisation of a novel peptide transporter from zebra¢sh, orthologue to mammalian and avian PEPT1. Zebra¢sh PEPT1 is a lowa⁄nity/high-capacity system. However, in contrast to higher vertebrate counterparts in which maximal transport activity is independent of extracellular pH, zebra¢sh PEPT1 maximal transport rates unexpectedly increase at alkaline extracellular pH. Zebra¢sh pept1 is highly expressed in the proximal intestine since day 4 post-fertilisation, thus preceding functional maturation of the gut, ¢rst feeding and complete yolk resorption. Zebra¢sh PEPT1 might help to understand the evolutionary and functional relationships among vertebrate peptide transporters. Moreover, zebra¢sh pept1 can be a useful marker for screening mutations that a¡ect gut regionalisation, di¡erentiation and morphogenesis. ß

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Here we demonstrated, by RT-PCR analysis, the expression of both angiotensin II (Ang II) receptor subtypes, AT1 and AT2, in a breast cancer epithelial cell line, MCF-7. Ang II was not able to affect the intracellular Ca 2+ concentration in Fura-2 loaded cells suggesting that AT1-mediated phospholipid hydrolysis is not involved in its intracellular transduction pathway. Ang II modulated the activity of the Na + /K + ATPase in a dose-and timedependent manner and was mitogenic, with a dosedependent (1-1000 nM) proliferative effect and a maximal response at 100 nM. Both Na + /K + ATPase activation and stimulation of proliferation were mediated by binding of Ang II to AT1, as the effects were completely blocked by DuP 753, a specific AT1 antagonist. CGP 42112, an AT2 antagonist, did not affect Ang II actions.The main conclusion of this study is that Ang II exerts its effects on cell proliferation and Na + /K + ATPase in breast cancer epithelial cells, MCF-7, via AT1 activation independently of the Ca 2+ signalling mechanism.

In the human vascular endothelium, statins reduce COX-2 and MMP-9 expression and activity. Through this mechanism, statins exert an anti-angiogenic effect possibly contributing to the cholesterol-lowering-unrelated protective effects of statins against plaque inflammatory angiogenesis and rupture.

Angiotensin II (Ang II) induces, through AT1, intracellular Ca(2+) increase in both normal and cancerous breast cells in primary culture (Greco et al., 2002 Cell Calcium 2:1-10). We here show that Ang II stimulated, in a dose-dependent manner, the 24 h-proliferation of breast cancer cells in primary culture, induced translocation of protein kinase C (PKC)-alpha, -beta1/2, and delta (but not -epsilon, -eta, -theta, -zeta, and -iota), and phosphorylated extracellular-regulated kinases 1 and 2 (ERK1/2). The proliferative effects of Ang II were blocked by the AT1 antagonist, losartan. Also epidermal growth factor (EGF) had mitogenic effects on serum-starved breast cancer cells since induced cell proliferation after 24 h and phosphorylation of ERK1/2. The Ang II-induced proliferation of breast cancer cells was reduced by (a) Gö6976, an inhibitor of conventional PKC-alpha and -beta1, (b) AG1478, an inhibitor of the tyrosine kinase of the EGF receptor (EGFR), and (c) downregulation of 1,2-diacylglycerol-sensitive PKCs achieved by phorbol 12-myristate 13-acetate (PMA). A complete inhibition of the Ang II-induced cell proliferation was achieved using the inhibitor of the mitogen activated protein kinase kinase (MAPKK or MEK), PD098059, or using Gö6976 together with AG1478. These results indicate that in human primary cultured breast cancer cells AT1 regulates mitogenic signaling pathways by two simultaneous mechanisms, one involving conventional PKCs and the other EGFR transactivation.