Is there an association between antiphospholipid antibodies and psoriasis?

Ever increasing evidence supports the association between psoriasis and cardiovascular risk. Antiphospholipid antibodies (APAs), which can occur in many autoimmune diseases, are considered prothrombotic and have been associated with atherosclerosis. The aim of this study is to evaluate the prevalence and levels of APAs in psoriasis patients. Fifty patients with moderate to severe plaque psoriasis and 48 healthy subjects were investigated for lupus anticoagulant (LAC) by screening and confirmatory coagulation tests, as well as for antibodies against cardiolipin or beta2-glycoprotein I. Levels of APAs and LAC-related parameters were similar for patients with psoriasis and normal controls (p>0.05). APAs were found in only one psoriatic patient (2%) and in none of the controls. LAC was detected in 2 patients (4%) and in one subject of the control group (2.1%). These results suggest that the prevalence of APAs is not increased in plaque psoriasis as compared to the control group. The increased cardiovascular risk observed in psoriatic patients is therefore likely to be correlated to factors different from APAs.     

15-deoxy-delta 12,14-prostaglandin J(2) inhibits the synthesis of the acute phase protein SIP24 in cartilage: Involvement of COX-2 in resolution of inflammation

We previously demonstrated that, in the MC615 cartilage cell line, the p38/NF-kB pathway is activated both during differentiation and in response to an inflammatory stimulus. In both cases, the p38/NF-kB pathway activation leads to the expression of the lipocalin SIP24 and of COX-2. Given the fact that, in the same cells, the COX-2 expression is sustained during the inflammation resolution, at the same time that the SIP24 expression is suppressed, in the present study we tested the hypothesis that COX-2 products play a role in SIP24 repression. Taken together, our results suggest that, during the resolution of inflammation, COX-2 represses the acute phase protein SIP24 and restores physiological conditions, possibly through a pathway involving PPARgamma. Experimental evidences being the following: (1) 15-deoxy-delta 12,14-prostaglandin J(2), but not PGE(2): (i) inhibits the expression of SIP24 in the inflammatory phase and induces COX-2 synthesis; (ii) represses NF-kB activation induced by LPS; (iii) represses the synthesis of microsomal PGE Synthase-1 induced by LPS. (2) PPARgamma and PPARalpha are present in MC615 cells in both proliferating and hyperconfluent cultures. (3) PPARgamma ligand GW7845, but not PPARalpha ligand GW7647: (i) represses the expression of SIP24 induced by LPS; (ii) induces COX-2 expression. (4) p38 is involved in the PPARgamma mediated induction of COX-2. In fact 15-deoxy-delta 12,14-prostaglandin J(2) activates p38 and the cell pretreatment with the p38 specific inhibitor SB203580 represses the expression of COX-2 induced by both the 15-deoxy-delta12,14-prostaglandin J(2) and the PPARgamma ligand GW7845.     

Iron deficiency differently affects peroxidase isoforms in sunflower

The response of both specific (ascorbate peroxidase, APX) and unspecific (POD) peroxidases and H(2)O(2) content of sunflower plants (Helianthus annuus L. cv. Hor) grown hydroponically with (C) or without (-Fe) iron in the nutrient solution were analysed to verify whether iron deficiency led to cell oxidative status. In -Fe leaves a significant increase of H(2)O(2) content was detected, a result confirmed by electron microscopy analysis. As regards extracellular peroxidases, while APX activity significantly decreased, no change was observed in either soluble guaiacol or syringaldazine-dependent POD activity following iron starvation. Moreover, guaiacol-dependent POD activity was found to decrease in both ionically and covalently-cell-wall bound fractions, while syringaldazine-POD activity decreased only in the covalently-bound fraction. At the intracellular level both guaiacol-POD and APX activities underwent a significant decrease. The overall reduction of peroxidase activity was confirmed by the electrophoretic separation of POD isoforms and, at the extracellular level, by cytochemical localization of peroxidases by diaminobenzidine staining. The electrophoretic separation, besides quantitative differences, also revealed quantitative changes, particularly evident for ionically and covalently-bound fractions. Therefore, in sunflower plants, iron deficiency seems to affect the different peroxidase isoenzymes to different extents and to induce a secondary oxidative stress, as indicated by the increased levels of H(2)O(2). However, owing to the almost completely lack of catalytic iron capable of triggering the Fenton reaction, iron-deficient sunflower plants are probably still sufficiently protected against oxidative stress.     

Structure elucidation and phytotoxicity of C13 nor-isoprenoids from Cestrum parqui

Twelve C(13) nor-isoprenoids have been isolated from the leaves of Cestrum parqui (Solanaceae). The structure (2R,6R,9R)-2,9-dihydroxy-4-megastigmen-3-one has been assigned to the new compound. All the structures have been determined by spectroscopic means and chemical correlations. The compounds showed phytotoxic effect on the germination and growth of Lactuca sativa L.     

Redundancy in the function of mitochondrial phosphate transport in Saccharomyces cerevisiae and Arabidopsis thaliana

Most cellular ATP is produced within the mitochondria from ADP and Pi which are delivered across the inner-membrane by specific nuclearly encoded polytopic carriers. In Saccharomyces cerevisiae, some of these carriers and in particular the ADP/ATP carrier, are represented by several related isoforms that are distinct in their pattern of expression. Until now, only one mitochondrial Pi carrier (mPic) form, encoded by the MIR1 gene in S. cerevisiae, has been described. Here we show that the gene product encoded by the YER053C ORF also participates in the delivery of phosphate to the mitochondria. We have called this gene PIC2 for Pi carrier isoform 2. Overexpression of PIC2 compensates for the mitochondrial defect of the double mutant Deltamir1 Deltapic2 and restores phosphate transport activity in mitochondria swelling experiments. The existence of two isoforms of mPic does not seem to be restricted to S. cerevisiae as two Arabidopsis thaliana cDNAs encoding two different mPic-like proteins are also able to complement the double mutant Deltamir1 Deltapic2. Finally, we demonstrate that Pic2p is a mitochondrial protein and that its steady state level increases at high temperature. We propose that Pic2p is a minor form of mPic which plays a role under specific stress conditions.     

Macromolecular and solution properties of Cepacian: the exopolysaccharide produced by a strain of Burkholderia cepacia isolated from a cystic fibrosis patient

Light scattering and viscosity measurements were carried out on the previously chemically characterised exopolysaccharide produced by a strain of Burkholderia cepacia isolated from a cystic fibrosis patient. The same exopolysaccharide was also produced by other clinical strains in different laboratories. Therefore, the name Cepacian is now proposed for this exopolysaccharide. Experiments performed as a function of the ionic strength on the native polymer revealed a change in the overall shape of the polymer at low ionic strength. This behaviour was absent in the de-acetylated sample. Potentiometric titrations and light scattering experiments carried out on the acidic form of the native polymer revealed the formation of macromolecular aggregates with a stoichiometry n and 2n stabilised by interactions involving the uronic acid residues.     

Cinnamic acid amides from Chenopodium album: effects on seeds germination and plant growth

Seven cinnamic acid amides have been isolated from Chenopodium album. The structures have been attributed by means of their spectral data. One of them, N-trans-4-O-methylferuloyl 4′-O-methyldopamine, is described for the first time. Their effects on germination and growth of dicotyledons Lactuca sativa L. (lettuce) and Lycopersicon esculentum L. (tomato) and of monocotyledon Allium cepa L. (onion) as standard target species have been studied in the range concentration 10⁻⁴-10⁻⁷ M.     

Chenoalbicin, a novel cinnamic acid amide alkaloid from Chenopodium album

The roots of Chenopodium album were infused in MeOH, and the extract was partitioned between AcOEt and H2O. AcOEt-Soluble material was subjected to different silica-gel column chromatographies and then purified by reverse-phase HPLC to afford a new cinnamic acid amide alkaloid as a racemic mixture. The new compound, named chenoalbicin (1), was characterized by extensive spectroscopic investigation, especially 1D and 2D NMR spectroscopy. Its effects on the germination and growth of Lactuca sativa L. has been studied. The results are reported as percentage differences of germination, root elongation, and shoot elongation from the control at concentrations ranging from 10(-4) to 10(-7) M.