Cigarette smoke is an aerosol that contains >4,000 chemicals, including nicotine, carbon monoxide, acrolein, and oxidant compounds. Exposure to cigarette smoke induces multiple pathological effects in the endothelium, several of which are the result of oxidative stress initiated by reactive oxygen species, reactive nitrogen species, and other oxidant constituents of cigarette smoke. Cigarette-smoke exposure interferes adversely with the control of all stages of plaque formation and development and pathological thrombus formation. The reactive oxygen species in cigarette smoke contribute to oxidative stress, upregulation of inflammatory cytokines, and endothelial dysfunction, by reducing the bioavailability of nitric oxide. Plaque formation and the development of vulnerable plaques also result from exposure to cigarette smoke via the enhancement of inflammatory processes and the activation of matrix metalloproteases. Moreover, exposure to cigarette smoke results in platelet activation, stimulation of the coagulation cascade, and impairment of anticoagulative fibrinolysis. Many cigarette-smoke-mediated prothrombotic changes are quickly reversible upon smoking cessation. Public health efforts should urgently promote our understanding of current cigarette-smoke-induced cardiovascular pathology to encourage individuals to reduce their exposure to cigarette smoke and, therefore, the detrimental consequences of associated atherothrombotic disease.

Basic proteins normally lost by the cathodic drift of carrier ampholyte focusing, or separated by NEPHGE with limited reproducibility, could be well separated by two-dimensional (2-D) electrophoresis under equilibrium conditions using immobilized pH gradients (IPGs) 4-10 and 6-10 using a previously published protocol (Görg et al., Electrophoresis 1988, 9, 531-546). In the present study we have extended the pH gradient to pH 12 with IPGs 8-12, 9-12 and 10-12 for the analysis of very basic proteins. Different optimization steps with respect to pH engineering, gel composition and running conditions, such as substitution of acrylamide by dimethylacrylamide and addition of isopropanol with and without methylcellulose to the IPG rehydration solution (in order to suppress the reverse electroosmotic flow) were necessary to obtain highly reproducible 2-D patterns of ribosomal proteins from HeLa cells and mouse liver. Histones from chicken erythrocyte nuclei as well as total cell extracts of erythrocytes were also successfully separated under steady-state conditions. Due to the selectivity of isoelectric focusing in IPG 9-12, where the more acidic proteins abandon the gel, the tedious procedure of nuclei preparation prior to histone extraction can be omitted.

We report that resveratrol (3,5,4'-trihydroxy-trans-stilbene), a phytoalexin found in grapes and other plant food, induced a breakdown of the mitochondrial transmembrane potential (∆Ψ m ) in T-acute lymphoblastic leukemia cells and swelling of isolated rat mitochondria. The breakdown of ∆Ψ m was accompanied by the production of reactive oxygen species (ROS), and preceded phosphatidylserine exposure and DNA fragmentation. Breakdown of ∆Ψ m was not caused by the activation of caspase-8 or Bid, as no significant cleavage of these proteins could be detected in the induction phase of resveratrol-induced apoptosis. Though loss of ∆Ψ m was not followed by cytochrome c translocation to the cytosol, the mitochondrial changes triggered significant activation of caspase-9, -2, -3, and -6. Inhibition of ∆Ψ m breakdown and of ROS generation by N-acetylcysteine, or by overexpression of Bcl-2 protein, prevented apoptosis induction by resveratrol. The Bcl-2 expression status of tumor cells should therefore be considered relevant for potential clinical application of resveratrol as anticancer agent.Key words: cell death • antioxidant • cytochrome c-independent • lymphoblastic leukemia esveratrol, a polyphenolic compound present in grapes and in red wine, has been found to inhibit cellular events that increase the risk of carcinogenesis, a finding that has initiated numerous studies on its molecular mechanisms. These studies revealed antioxidant activities such as the inhibition of free radical formation following TPA stimulation (1) and of peroxidation of lipids in microsomes and of plasma LDL (2). Further mechanisms of action comprise modulation of lipoprotein metabolism and inhibition of platelet aggregation and coagulation (3). Its chemopreventive properties have been demonstrated in vitro, where R resveratrol lowers the mutagenic responses induced in salmonella by the aryl hydrocarbon dimethylbenz[a]anthracene treatment and induces quinone reductase activity (an enzyme capable of detoxifying carcinogens) (4). Moreover, it strongly inhibits P450-1A1 activity (an enzyme that transforms environmental toxins and procarcinogens into ultimate carcinogens), and it prevents dioxin toxicity by antagonistic activity on the aryl hydrocarbon receptor (5).More recently, its antioxidant and chemopreventive effects have been demonstrated in vivo by showing that it prevents the development of preneoplastic lesions in carcinogen-treated mouse mammary glands and inhibits tumorigenesis in a mouse skin cancer model (6). These results may be explained by its growth-inhibitory effects on tumor cell lines; by its capacity to directly induce apoptosis in various human tumor models, including promyelocytic leukemia (7), prostate cancer (8), and breast cancer (9, 10); and by its tumor specificity, because it does not affect human peripheral blood lymphocytes from healthy donors (9). The growth-inhibitory effect of resveratrol might result from its influence on the expression levels or phosphorylation status of cell cycle regulators such as cyclin E, c...

INTRODUCTION: CONSERVED CHARACTER OF MULTIPLE ACETYLATION POSITIONS OF CORE HISTONES Organization of the eukaryotic genome and histone structure at different chromatin regions is possible and acetylations occur with different turnover. Distinctly different acetylation patterns emerge when species, cell lines, different physiological situations and chromatin fractions are compared. The actual acetylation pattern is determined by the available acetylation positions on the one side, and the activities of histone acetyltransferase(s) and deacetylase(s) on the other. Thus, the regulation of histone acetylation is conceivable either at the level of chromatin structure, or alternatively at the level of Vol. 265