This study investigated the possible active principles which support the endothelial nitric oxide-dependent relaxation produced by red wine and other plant polyphenolic compounds in thoracic aorta from male Wistar rats (12-14 wk old). Relaxation experiments were recorded isometrically on vessels precontracted with norepinephrine. Ten different chromatographic fractions (3-18 mg) isolated from red wine polyphenolic compounds (RWPC) and some available defined polyphenols (10-15 mg) were tested. Fractions enriched into either anthocyanins or oligomeric condensed tannins exhibited endothelium-dependent vasorelaxant activity (maximal relaxation in the range of 59-77%) comparable to the original RWPC. However, polymeric condensed tannins elicited a weaker vasorelaxant activity than the original RWPC (maximal relaxation ranged between 20-47%, P < 0.01). Moreover, the representative of either phenolic acid derivatives (benzoic acid, vanillic acid, gallic acid), hydroxycinnamic acid (p-coumaric acid, caffeic acid) or the flavanol [(+)-epicatechin] classes failed to induce this type of response. Among the anthocyanins, delphinidin (maximal relaxation being 89%), but not malvidin or cyanidin, showed endothelium-dependent vasorelaxation. These results show that anthocyanins and oligomeric-condensed tannins exhibited a pharmacological profile comparable to the original RWPC. These compounds may be involved in the reduction of cardiovascular mortality related to the presence of wine, fruits and vegetables in the diet.

In order to examine the possible implication of human epithelial and endothelial cells in the pathogenesis of various diseases associated with oral viridans streptococci, we tested the immunomodulatory effects of 11 representative strains of oral viridans streptococci on human epithelial KB cells and endothelial cells. We then examined the possible role of two major adhesins from oral viridans streptococci, protein I/II and rhamnoseglucose polymers (RGPs), in this process. In this study we demonstrate that oral viridans streptococci are potent stimulators of interleukin-8 (IL-8) production from KB cells and of IL-6 and IL-8 production from endothelial cells. The ability of protein I/II and RGPs to contribute to these effects was then examined. Using biotinylated protein I/IIf and RGPs from Streptococcus mutans OMZ 175, we showed that these adhesins bind to KB and endothelial cells through specific interactions and that the binding of these molecules initiates the release of IL-8 from KB cells and of IL-6 and IL-8 from endothelial cells. These results suggest that protein I/IIf and RGPs play an important role in the interactions between bacteria and KB and endothelial cells in that similar cytokine profiles are obtained when cells are stimulated with bacteria or surface components. We also provide evidence that protein I/IIf binds to and stimulates KB and endothelial cells through lectin interactions and that N-acetyl neuraminic acid (NANA) and fucose present on cell surface glycoproteins may form the recognition site since binding and cytokine release can be inhibited by dispase and periodate treatment of cells and by NANA and fucose. These results demonstrate that oral viridans streptococci, probably by engaging two cell surface adhesins, exert immunomodulatory effects on human KB and endothelial cells.

In order to examine the possible implication of capsular polysaccharide (CP) types 5 and 8 (CP5 and CP8) from Staphylococcus aureus in the pathological mechanism associated with staphylococcal infections, we tested the immunomodulatory effects of CP5 and CP8 on human epithelial KB cells, endothelial cells, and monocytes. Using biotinylated CP5 and CP8, we provide evidence that both CPs bind to KB cells, endothelial cells, and monocytes in a dose-and calcium-dependent manner through specific interactions. These results were confirmed by competition experiments using soluble cell extracts. Furthermore, we show that CPs bind to identical cell membrane receptors on all three types of human cells and that human normal serum contains a factor(s) which inhibits the binding of both CPs to human KB cells, endothelial cells, and monocytes. The ability of CP5 and CP8 to stimulate the production of cytokines by the human cells was then examined. CP5 and CP8 trigger KB cells to produce interleukin-8 (IL-8); endothelial cells to produce IL-8 and IL-6; and monocytes to produce IL-8, IL-6, IL-1␤, and tumor necrosis factor alpha. The release of cytokines by all three types of cells is time dependent and dose dependent, and the tumor necrosis factor alpha production by monocytes is not affected by the addition of polymyxin B. We further confirm that human normal serum inhibits the immunomodulatory effects of both polysaccharides on each kind of cell. These results confirm that S. aureus CPs act as bacterial adhesins having immunomodulatory effects for human cells.

Abstract-CD9, a member of the tetraspanin family, and very late-acting (VLA) integrins are known to associate and form functional units on the surface of several cell types. We studied the changes in expression of CD9 and ␤ 1 -integrins (CD29, VLA) in human vascular smooth muscle cells (VSMCs) under in vitro culture conditions mimicking proliferative vascular diseases. We also investigated possible interactions between CD9 and VLA integrins in VSMCs. We found that CD9 is highly expressed in VSMCs and is subject to modulation, depending on the proliferative/ contractile state of the cells. In the contractile phenotype, the levels of CD9, CD81, another tetraspanin, and CD29 are Ϸ50% of those found in the proliferative phenotype. Coimmunoprecipitation experiments showed physical association between CD9 and CD29. CD9 was mainly associated with ␣ 2 and ␣ 3 -integrins (CD49b and c) and also with ␣ 5 -integrin to a weaker extent. Functionally, the addition of anti-CD9 monoclonal antibodies (MoAbs) doubled the extent of collagen gel contraction mediated by VSMCs, a model for the reorganization of the extracellular collagen matrix occurring in the vessel wall. Anti-CD29 MoAbs inhibited gel contraction, but anti-CD9 MoAbs counteracted this inhibitory effect of anti-CD29 MoAbs. Transfection of human CD9 into Chinese hamster ovary cells more than doubled the extent of Chinese hamster ovary cell-mediated collagen gel contraction (130% stimulation), confirming a role for CD9 in extracellular matrix reorganization. Thus, CD9 seems to be involved in the modulation of VLA integrinmediated collagen matrix reorganization by VSMCs. These findings suggest that high CD9 expression is associated with a proliferative state of VSMCs. The role of CD9 could be to modulate the function of VLA integrins on the surface of VSMCs.

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Among the 12 subfamilies currently considered in the systematics of Poaceae, the Arundinoideae have long been considered as a dustbin group, with a diversity of forms putatively hiding incertae sedis. Because this subfamily has been poorly investigated using molecular markers for the last two decades, the present study provides the first complete phylogeny of the Arundinoideae based on five plastid DNA loci sequenced for 12 genera, and analysed with and without plastome data from previous studies. The refined Arundinoideae appear to be a robust evolutionary lineage of Poaceae, divided into three tribes with some biogeographical patterns: (1) tribe Arundineae, the most heterogeneous tribe, including Eurasian Arundo, Australian Amphipogon and Monachather, and South African Dregeochloa; (2) tribe Crinipedeae (described here), including Crinipes, Elytrophorus, Styppeiochloa and Pratochloa (described here), with a South and East African distribution; and (3) tribe Molinieae, including Hakonechloa, Molinia and Phragmites, with a Eurasian distribution. Despite reduction in size, this small subfamily conserves a high diversity of morphological forms, with several small but highly differentiated genera. Finally, the molecular dating approach provides an evolutionary framework to understand the diversification of Arundinoideae, refuting Gondwanan vicariance between genera and suggesting capability for long distance dispersal.

The systematics of Arundinoideae (Poaceae), a subfamily long considered as a dustbin group, has been progressively resolved in recent decades. The last members incertae sedis of Arundinoideae are two African species not observed for &gt; 150 years and currently studied only on the basis of old herbarium specimens. Based on the sequencing of its whole plastid genome, Leptagrostis schimperiana was placed in the monophyletic Crinipedeae (Arundinoideae) in the grass plastome phylogenetic tree. To date, whole plastome sequencing based on a 167-year-old herbarium specimen is a new record. Using a morphological cladistic approach based on 51 morphological and anatomical characters, we confirmed the position of Leptagrostis schimperiana and showed that Piptophyllum welwitschii is also a member of Crinipedeae.

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