Poly (ADP-ribose) polymerase-1 is a nuclear DNAbinding protein that participates in the DNA base excision repair pathway in response to genotoxic stress in mammalian cells. Here we show that PARP-1-deficient cells are defective in NF-κB-dependent transcription activation, but not in its nuclear translocation, in response to TNF-α. Treating mice with lipopolysaccharide (LPS) resulted in the rapid activation of NF-κB in macrophages from PARP-1 ⍣/⍣ but not from PARP-1 -/-mice. PARP-1-deficient mice were extremely resistant to LPS-induced endotoxic shock. The molecular basis for this resistance relies on an almost complete abrogation of NF-κB-dependent accumulation of TNF-α in the serum and a downregulation of inducible nitric oxide synthase (iNOS), leading to decreased NO synthesis, which is the main source of free radical generation during inflammation. These results demonstrate a functional association in vivo between PARP-1 and NF-κB, with consequences for the transcriptional activation of NF-κB and a systemic inflammatory process.

1 The aim of this work was to investigate the mechanism of vasorelaxation induced by red wine polyphenolic compounds (RWPC) and two de®ned polyphenols contained in wine, leucocyanidol and catechin. The role of the endothelium, especially endothelium-derived nitric oxide (NO), was also investigated. 2 Relaxation produced by polyphenols was studied in rat aortic rings with and without functional endothelium, pre-contracted to the same extent with noradrenaline (0.3 and 0.1 mM, respectively). RWPC and leucocyanidol, but not catechin, produced complete relaxation of vessels with and without endothelium. However, 1000 fold higher concentrations were needed to relax endothelium-denuded rings compared to those with functional endothelium. 3 High concentrations of catechin (in the range of 10 71 g l 71 ) only produced partial relaxation (maximum 30%) and had the same potency in rings with and without endothelium. 4 The NO synthase inhibitor, N o -nitro-L-arginine-methyl-ester (L-NAME, 300 mM) completely abolished the endothelium-dependent but not the endothelium-independent relaxations produced by all of the polyphenolic compounds. 5 In contrast to superoxide dismutase (SOD, 100 u ml 71 ), neither RWPC nor leucocyanidol a ected the concentration-response curve for the NO donor, SIN-1 (3-morpholino-sydnonimine) which also produces superoxide anion (O 2 7 ). 6 In aortic rings with endothelium, RWPC (10 72 g l 71 ) produced a 7 fold increase in the basal production of guanosine 3' : 5'-cyclic monophosphate (cyclic GMP) which was prevented by L-NAME (300 mM). 7 Electron paramagnetic resonance (e.p.r.) spectroscopy studies with Fe 2+ -diethyldithiocarbamate as an NO spin trap demonstrated that RWPC and leucocyanidol increased NO levels in rat thoracic aorta about 2 fold. This NO production was entirely dependent on the presence of the endothelium and was abolished by L-NAME (300 mM). 8 These results show that RWPC and leucocyanidol, but not the structurally closely related polyphenol catechin, induced endothelium-dependent relaxation in the rat aorta. They indicate that this e ect results from enhanced synthesis of NO rather than enhanced biological activity of NO or protection against breakdown by O 2 7 . It is concluded that some polyphenols, with speci®c structure, contained in wine possess potent endothelium-dependent vasorelaxing activity.

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.

The mechanisms by which red wine polyphenolic compounds (RWPCs) induced endothelium-dependent relaxation were investigated in rat thoracic aorta rings with endothelium. RWPCs produced relaxation that was prevented by the nitric oxide (NO) synthase inhibitor, N(omega)-nitro-L-arginine-methyl-ester. This relaxation was abolished in the absence of extracellular calcium in the medium or in the presence of the Ca2+ entry blocker, La3+, but it was not affected by the nonselective K+ channels blocker, tetrabutylammonium. N-Ethyl-maleimide (NEM), a sulfhydryl alkylating agent, abolished vasorelaxation produced by RWPCs and acetylcholine but not that produced either by the sarcoendoplasmic reticulum Ca2+-adenosine triphosphatase (ATPase) pump inhibitor, cyclopyazonic acid (CPA) or the calcium ionophore, ionomycin. Neither pertussis toxin (PTX) nor cholera toxin (CTX) inhibited the vasorelaxant effect of RWPC. The effect of RWPC was not affected by the phospholipase C (PLC) blocker, L-alpha-glycerophospho-D-myo-inositol 4-monophosphate (Gro-pip), and the phospholipase A2 pathway blockers, quinacrine and ONO-RS-082. Finally, the protein kinase C (PKC) inhibitor, GF 109203X, and tyrosine kinase inhibitors, tyrphostin A-23 and genistein, did not impair the response to RWPCs. These results suggest that RWPCs produce endothelium-NO-derived vasorelaxation through an extracellular Ca2+-dependent mechanism via an NEM-sensitive pathway. They also show that PTX- or CTX-sensitive G proteins, activation of PLC or PLA2 pathways, PKC, or tyrosine kinase may not be involved.