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Biomedical subjects

Salvatore De Rosa

Publications and source records attributed to Salvatore De Rosa.

At least 19 recordsLinked to original sources
PubMed2006

Identification of avarol derivatives as potential antipsoriatic drugs using an in vitro model for keratinocyte growth and differentiation.

Avarol, a marine sesquiterpenoid hydroquinone, and 14 avarol derivatives have shown interesting anti-inflammatory properties in previous studies. In this study, avarol and derivatives were evaluated in high-throughput keratinocyte culture models using cytokeratin 10 and SKALP/Elafin expression as markers for respectively normal and psoriatic differentiation. Avarol and five of its derivatives (5, 10, 13, 14 and 15) were selected for further study. Only 10, 13, 14 and 15 were able to inhibit keratinocyte cell growth. Changes in expression levels of 22 genes were assessed by quantitative real time PCR (qPCR). From these genes, TNFalpha mRNA levels showed the strongest changes. For compound 13, 15 and dithranol (used as a model antipsoriatic drug), a dose-dependent downregulation of TNFalpha mRNA was found. The changes in TNFalpha mRNA were confirmed at the protein level for compound 13. Additionally, this compound was able to reduce also IL-8 and COX-2 mRNA levels and this effect was correlated with a reduction in COX-2 protein expression. The mechanism of action of this compound involves at least the inhibition of NF-kappaB-DNA binding activity. In conclusion, our high-throughput screening models in combination with quantitative assessment of changes in gene expression profiles identified the avarol derivative 13, a benzylamine derivative of avarol at the 4' position of benzoquinone ring, as an interesting anti-psoriatic drug candidate that inhibits keratinocyte cell growth and TNFalpha and COX-2 expression.

Animals↗
PubMed2006

Bioactive exopolysaccharides from the cultured cells of tomato, Lycopersicon esculentum var. San Marzano.

Three exopolysaccharides, EPS(1), EPS(2), and EPS(3), were isolated from suspension-cultured cells of tomato (Lycopersicon esculentum, var. San Marzano). The partial primary structures were determined on the basis of spectroscopic analyses. EPS(2) was a heteropolysaccharide with a tetrasaccharide repeating unit constituted by sugars having one residue in alpha-manno, one residue in beta-manno, and two different residues in beta-gluco/galacto configurations. EPS(3) was a heteropolysaccharide with a pentasaccharide repeating unit with sugars having three residues in alpha-manno, one residue in alpha-gluco/galacto, and one residue in beta-gluco/galacto configurations. The anticytotoxic activities of exopolysaccharides were tested in a brine shrimp bioassay.

Animals↗
PubMed2005

Chemical pretreatment of olive oil mill wastewater using a metal-organic framework catalyst.

Olive oil mill wastewaters (OOMW) are not suited for direct biological treatment because of their nonbiodegradable and phytotoxic compound (such as polyphenols) content. Advanced technologies for treatment of OOMW consider mainly the use of solid catalysts in processes that can be operated at room conditions. A system based on combined actions of catalytic oxidations and microbial technologies was studied. The wet hydrogen peroxide catalytic oxidation (WHPCO) process is one of the new emerging oxidation processes particularly attractive for the pretreatment of highly polluted OOMW containing polyphenols that are not suited for classical treatments. In this work, the biodegradability of OOMW was evaluated before and after treating the wastewater samples by the WHPCO process using a metal-organic framework (MOF) as a catalyst. This material, containing Cu and prepared with benzene-1,3,5-tricarboxylic acid (BTC), is a robust metal-organic polymer with a microporous structure that is reminiscent of the topology of zeolite frameworks.

Catalysis↗
PubMed2005

C-reactive protein induces tissue factor expression and promotes smooth muscle and endothelial cell proliferation.

OBJECTIVE: Inflammation plays a pivotal role in atherothrombosis. In addition to being a prognostic marker for major cardiovascular events, recent data indicate that C-reactive protein (CRP) might directly promote atherothrombosis by exerting direct effects on vascular cells. The aim of the present study was to determine whether CRP might affect the prothrombotic and proliferative characteristics of endothelial (ECs) and smooth muscle cells (SMCs). METHODS AND RESULTS: Incubation of ECs and SMCs with CRP resulted in a dose-dependent activation of cell proliferation, which was mediated by activation of the p44/42 MAP Kinase (ERK 1/2) pathway. In addition, CRP also induced tissue factor (TF) expression in both cell types in a dose-dependent fashion, exerting its effect at the transcriptional level, as demonstrated by semiquantitative and by real time PCR. Activation of the transcription factor, NF-kappaB, by CRP was demonstrated by EMSA and by suppression of TF expression by the NF-kappaB inhibitor, pyrrolidine-dithio-carbamate ammonium. CONCLUSIONS: These data indicate that CRP exerts direct effects on ECs and SMCs by promoting proliferation and TF expression and support the notion that CRP, besides representing a marker of inflammation, is an effector molecule able to induce a pro-atherothrombotic phenotype in cells of the vessel wall.

Animals↗
PubMed2005

Exocellular peptides from Antarctic psychrophile Pseudoalteromonas Haloplanktis.

A novel diketopiperazine, named cyclo-(D-pipecolinyl-L-isoleucine) (DKP 1), and 7 known diketopiperazines were isolated from the cell-free culture supernatant of the Antarctic psychrophilic bacterium Pseudoalteromonas haloplanktis TAC125. Two diketopiperazines containing pipecolinyl moiety were isolated for the first time from a natural source. Two new linear peptides, stable to bacterial proteolytic enzymes, were also characterized. The structures of the isolated compounds were elucidated by means of spectroscopic data (1D-, 2D-NMR, EIMS, FABMS, and ESIMS/MS) and chiral high-performance liquid chromatography. The potential antioxidant activity of the isolated compounds was evaluated by a DPPH free radical scavenging assay.

Amino Acid Sequence↗
PubMed2004

Tissue factor binding of activated factor VII triggers smooth muscle cell proliferation via extracellular signal-regulated kinase activation.

BACKGROUND: Tissue factor (TF) is the main initiator of coagulation in vivo. Recently, however, a role for TF as a cell receptor involved in signal transduction has been suggested. The aim of the present study was to assess whether activated factor VII (FVIIa) binding to TF could induce smooth muscle cell (SMC) proliferation and to clarify the possible intracellular mechanism(s) responsible for this proliferation. METHODS AND RESULTS: Cell proliferation was induced by FVIIa in a dose-dependent manner, as assessed by [3H]thymidine incorporation and direct cell counting, whereas no response was observed with active site-inhibited FVIIa (FVIIai), which is identical to FVIIa but is devoid of enzymatic activity. Similarly, no proliferation was observed when binding of FVIIa to TF was prevented by the monoclonal anti-TF antibody AP-1. Activation of the p44/42 mitogen-activated protein (MAP) kinase (extracellular signal-regulated kinases 1 and 2 [ERK 1/2]) pathway on binding of FVIIa to TF was demonstrated by transient ERK phosphorylation in Western blots and by suppression of proliferation with the specific MEK (MAP kinase/ERK kinase) inhibitor UO126. ERK phosphorylation was not observed with FVIIai or when cells were pretreated with AP-1. CONCLUSIONS: These data indicate a specific effect by which binding of FVIIa to TF on the surface of SMCs induces proliferation via a coagulation-independent mechanism and possibly indicate a new link between coagulation, inflammation, and atherosclerosis.

Animals↗
PubMed2004

Time trends in three triennial surveys of cardiovascular risk factors and their treatment among patients discharged from divisions of internal medicine The FAPOI-1, FADOI-2, and FADOI-3 studies.

BACKGROUND: There is increasing interest in monitoring cardiovascular risk factor levels and their treatment. We decided to study this in patients discharged from Divisions of Internal Medicine. METHODS: In three studies conducted in 1996, 1999, and 2002, data was collected on diagnoses of cardiovascular diseases and cardiovascular risk factor levels and treatment in 5904, 7476, and 9649 patients, respectively, aged 35 years or older, who were discharged within a week from 235, 345, and 517 Divisions of Internal Medicine in Italy. RESULTS: Between the first and third surveys, a relative decrease in atherosclerotic cardiovascular diseases was recorded, but heart failure showed a definite increase, reaching 11% of all cases. Mean levels of most cardiovascular risk factors decreased significant; only obesity did not. The proportion of treated hypertensives increased slightly (from 65% to 83% among men, and from 69% to 85% among women). The proportion of controlled hypertensives also rose, reaching around 37%. The proportion of treated dyslipidemics increased from 10% to 28% in men and from 12% to 25% in women, due to an increase in the use of statins. CONCLUSIONS: It is essential to focus attention on cardiovascular risk factors in order to optimize their treatment and to reduce cardiovascular disease.

Journal Article↗
PubMed2004

Potential antipsoriatic avarol derivatives as antioxidants and inhibitors of PGE(2) generation and proliferation in the HaCaT cell line.

The synthesis and structure-activity relationships for a series of 14 new avarol derivatives as antioxidants and inhibitors of cell proliferation and PGE(2) generation in human keratinocytes are described. Compound 6 (thiosalicylic derivative) was the most potent inhibitor of superoxide generation in human neutrophils and also potently inhibited PGE(2) generation in the human keratinocyte HaCaT cell line. Compound 7(3'-methylaminoavarone) presented the best antiproliferative profile, by the inhibition of (3)H-thymidine incorporation in HaCaT cells, with potency similar to the reference compound anthralin. None of the avarol derivatives showed any sign of cytotoxicity measured as LDH release in treated keratinocytes. The potency and pharmacological profile of derivatives are also discussed.

Antioxidants↗
PubMed2004

Cyclic peptides from a Ruegeria strain of bacteria associated with the sponge Suberites domuncula.

Two new cyclic peptides, cyclo-(glycyl-L-seryl-L-prolyl-L-glutamyl) and cyclo-(glycyl-L-prolyl-L-glutamyl), have been isolated from the cell extract of a Ruegeria strain associated with cell cultures of Suberites domuncula. Three other cyclopeptides have been isolated for the first time from a natural source. Additionally, a new diastereoisomer of a known compound is reported. The structures of isolated compounds have been elucidated by means of spectroscopic data (1D-, 2D-NMR, HRESIMS) and chiral HPLC analysis. The new cyclopeptides exhibited moderate antimicrobial activity against Bacillus subtilis.

Amino Acid Sequence↗
PubMed2004

Inhibition of the tissue factor coagulation pathway.

It is widely accepted that blood coagulation in vivo is initiated during normal hemostasis, as well as during intravascular thrombus formation, when the cell-surface protein, tissue factor, is exposed to the blood as a consequence of vascular injury. In addition to its essential role in hemostasis, tissue factor may be also implicated in several pathophysiological processes, such as intracellular signaling, cell proliferation, and inflammation. For these reasons, the tissue factor:factor VIIa complex has been the subject of intense research focus. Many experimental studies have demonstrated that inhibition of tissue factor:factor VIIa procoagulant activity are powerful inhibitors of in vivo thrombosis and that this approach usually results in less pronounced bleeding tendency, as compared to other "more classical" antithrombotic interventions. Alternative approaches may be represented by transfecting the arterial wall with natural inhibitors of tissue factor:factor VIIa complex, such as tissue factor pathway inhibitor, which may result in complete inhibition of local thrombosis without incurring in potentially harmful systemic effects. Additional studies are warranted to determine the efficacy and safety of such approaches in patients.

Animals↗
PubMed2003

Exocellular cyclic dipeptides from a Ruegeria strain associated with cell cultures of Suberites domuncula.

From cell cultures of Suberites domuncula was isolated a bacterial strain, SDC-1, which was identified by 16S ribosomal RNA sequence analysis as an alpha-Proteobacterium of the genus Ruegeria. The occurrence of the strain in sponge cell culture could be explained by its resistance to the antibiotics used in the isolation of sponge cell cultures or by the preservation of SDC-1 by host sponge cells. The fatty acid composition of SDC-1 is characterized by branched C-12 methyl fatty acids. Two new and 8 known cyclic dipeptides were isolated and characterized from the fermentation broth of SDC-1. Cyclodipeptides are one of the families of cell-cell signaling compounds and may have some role to play in sponge-bacteria interactions.

Animals↗
PubMed2003

Development in primary cell culture of demosponges.

We have established primary cell culture of the marine demosponge Dysidea avara and Suberites domuncula. Microbial contamination was controlled by the use of a pool of antibiotics confirming the goodness of this procedure. Effect of pH, temperature and light was studied to establish the better growth conditions. The comparison of lipid composition of sponge and cells suggested a series of experiments to optimise the medium. A glucose dose-dependent experiment showed that the ideal glucose concentration is 1 g l(-1). Supplementing the medium with unsaturated fatty acid and retinol, no promotion of growth was observed, but the compounds were totally metabolised by cells. Increments from 70 to 160% in the number of cells were observed, supplementing the medium with different concentration of cholesterol. These results suggest that the analysis of the chemical composition of sponge and cells give indication on the composition of the nutrient media.

Animals↗
PubMed2003

Activated platelets stimulate tissue factor expression in smooth muscle cells.

UNLABELLED: Tissue factor (TF)-induced activation of the coagulation plays a key role in the pathophysiology of acute coronary syndromes. Because TF represents the initial trigger of the coagulation cascade, its expression in the arterial wall is tightly regulated. OBJECTIVE: To determine whether and which soluble mediators released during platelet activation may upregulate TF expression in smooth muscle cells (SMCs). METHODS AND RESULTS: Rabbit SMCs were challenged with collagen-activated platelets and their effects on TF mRNA transcription and protein expression were evaluated at different time points (30 min, 1, 2, 4, 8, 12 and 24 h) by RT-PCR, immunofluorescence and a two-stage colorimetric assay. A progressive increase in TF mRNA, peaking at 2 h, was evident in SMCs stimulated with activated platelets with respect to baseline. The increase in TF mRNA expression was associated with a parallel increase in TF protein, as demonstrated by immunofluorescence and by colorimetric assay. In a different set of experiments, selected platelet-derived soluble mediators were shown to induce TF mRNA expression. CONCLUSIONS: Activated platelets upregulate TF, via release of several soluble mediators, in a cell population widely expressed in the vessel wall and in atherosclerotic plaques, such as SMCs. This phenomenon might play an important role in sustaining thrombus formation in vivo.

Animals↗
PubMed2003

Marine bacteria associated with sponge as source of cyclic peptides.

Two bacteria associated with the marine sponge Ircinia variabilis were isolated using commercial and experimental media. The use of media containing marine derived proteins improved the growth of both isolated bacteria, showing that marine bacteria need of marine derived proteins for a better growth. The composition of free and total fatty acids of both strains cultivated under different carbon source was investigated. Several diketopiperazines were isolated from both bacteria and the hypothesis of their role in the bacterial-spongy interaction is discussed.

Animals↗
PubMed2003

Cacospongionolide B suppresses the expression of inflammatory enzymes and tumour necrosis factor-alpha by inhibiting nuclear factor-kappa B activation.

1. The marine product cacospongionolide B, a sesterterpene isolated from the Mediterranean sponge Fasciospongia cavernosa, is an inhibitor of secretory phospholipase A(2) with anti-inflammatory properties. In this work, we have studied the mechanism of action of this compound in the inflammatory response induced by zymosan in primary cells and in the mouse air pouch. 2. In mouse peritoneal macrophages, cacospongionolide B was able to downregulate the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), resulting in decreased production of NO and prostaglandin E(2) (PGE(2)). This compound also reduced tumour necrosis factor-alpha (TNF-alpha) mRNA expression and TNF-alpha levels. 3. Cacospongionolide B inhibited nuclear factor-kappaB (NF-kappaB)-DNA binding activity and the nuclear translocation of this transcription factor. 4. Treatment of cells with cacospongionolide B impaired NF-kappaB inhibitory protein (IkappaB-alpha) phosphorylation and enhanced IkappaB-alpha expression. 5. Inhibition of iNOS, COX-2 and inflammatory mediators was confirmed in the mouse air pouch. 6. These results show that cacospongionolide B is able to control NO, PGE(2) and TNF-alpha production in vitro and in vivo, effects likely dependent on NF-kappaB inhibition.

4-Butyrolactone↗
PubMed2002

Coumarin glucosides from Cruciata taurica.

Two new coumarin glycosides (1 and 2) along with two known coumarin glucosides, daphnin (3) and daphnetin glucoside (4) were isolated from the aerial parts of Cruciata taurica. The structures of the new compounds were elucidated by spectral methods and chemical means as 7-O-(6' -acetoxy-beta-D-glucopyranosyl)-8-hydroxycoumarin (1) and 7-O-[6 '-O-(3'',4''-dihydroxycinnamoyl)-beta-D-glucopyranosyl]-8-hydroxycoumarin (2). The phylogenetic significance of coumarins in C. taurica was discussed.

Coumarins↗
PubMedDate not supplied

Chemical composition of Corallina mediterranea Areschoug and Corallina granifera Ell. et Soland.

The composition of sterols, volatiles and some polar compounds from three Corallina samples (C. granifera and C. mediterranea from the Black Sea and C. mediterranea from the Mediterranean Sea) was established. The sterol composition of the Black Sea samples was similar but it differs from that of the Mediterranean sample. The composition of the volatiles was very complex. The main groups of constituent were hydrocarbons, alcohols, carbonyl compounds, acids and their esters, terpenes. The composition of the polar components, soluble in n-butanol, was also established. There were some differences in the chemical composition of the two Black Sea species, which may be due to the biodiversity between them, while the differences in the composition of the two C. mediterranea samples could be due to the differences in the environment (salinity, temperature, pollution, etc.).

1-Butanol↗