showing 15 related works from this author
Synthesis and evaluation of diverse thio avarol derivatives as potential UVB photoprotective candidates.
2007
Semisynthesis of 13 new thio avarol derivatives (4-16) and in vitro evaluation on the photodamage response induced by UVB irradiation are described. Their ability to inhibit NF-kappaB activation and TNF-alpha generation in HaCaT cells as well as their antioxidant capacity in human neutrophils has also been studied. Among them we have identified two monophenyl thio avarol derivatives (4-5) lacking cytotoxicity which can be considered promising UVB photoprotective agents through the potent inhibition of NF-kappaB activation with a mild antioxidant pharmacological profile.
Suppression of leukotriene B4 and tumour necrosis factor alpha release in acute inflammatory responses by novel prenylated hydroquinone derivatives.
1998
A series of prenyl hydroquinone derivatives synthesized as structural analogs of marine products were tested for their effects on inflammatory responses in vitro and in vivo. 2-Prenyl-1,4-hydroquinone (H1), 2-diprenyl-1,4-hydroquinone (H2), 2-triprenyl-1,4-hydroquinone (H3) and 2-tetraprenyl-1,4-hydroquinone (H4) scavenged reactive oxygen species and inhibited 5-lipoxygenase (5-LO) activity in human neutrophils. The inhibition of 5-LO activity was demonstrated in vivo in the mouse air pouch injected with zymosan and arachidonic acid-induced ear inflammation. The four compounds suppressed the production of tumour necrosis factor alpha (TNFalpha) in J774 cells stimulated with lipopolysacchari…
Synthesis of the neurotoxin quinolinic acid in apoptotic tissue from Suberites domuncula: cell biological, molecular biological and chemical analyses
2002
Sessile marine animals, such as sponges, are prone to infection by prokaryotic as well as by eukaryotic attacking organisms. In the present study we document for the first time that in tissue from sponges which underwent apoptosis, a toxic compound is produced which very likely controls the elimination of the dying tissue. The marine sponge Suberites domuncula develops in the field occasionally apoptotic tissue areas which are rapidly eliminated. In the present study apoptosis was induced in S. domuncula by exposing the specimens in aquaria to 5 µg/ml Dip or by maintaining the sponges for 3 - 5 days under non-aeration conditions. After that treatment only one eukaryotic epibiont, the mollus…
Cacospongionolide B suppresses the expression of inflammatory enzymes and tumour necrosis factor-αby inhibiting nuclear factor-κB activation
2003
The marine product cacospongionolide B, a sesterterpene isolated from the Mediterranean sponge Fasciospongia cavernosa, is an inhibitor of secretory phospholipase A2 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. 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 E2 (PGE2). This compound also reduced tumour necrosis factor-α (TNF-α) mRNA expression and TNF-α levels. Cacosp…
Modulation of acute and chronic inflammatory processes by cacospongionolide B, a novel inhibitor of human synovial phospholipase A2
1999
Cacospongionolide B is a novel marine metabolite isolated from the sponge Fasciospongia cavernosa. In in vitro studies, this compound inhibited phospholipase A2 (PLA2), showing selectivity for secretory PLA2 (sPLA2) versus cytosolic PLA2 (cPLA2), and its potency on the human synovial enzyme (group II) was similar to that of manoalide. This activity was confirmed in vivo in the 8 h zymosan-injected rat air pouch, on the secretory enzyme accumulating in the pouch exudate. Cacospongionolide B, that is bioavailable when is given orally, reduced the elevated levels of sPLA2 present in paw homogenates of rats with adjuvant arthritis. This marine metabolite showed topical anti-inflammatory activit…
A New Cacospongionolide Inhibitor of Human Secretory Phospholipase A2 from the Tyrrhenian Sponge Fasciospongia cavernosa and Absolute Configuration o…
1998
A new inhibitor of human secretory phospholipase A2 (PLA2), cacospongionolide E (4a), has been isolated from the Tyrrhenian sponge Fasciospongia cavernosa. The structure was proposed on the basis of spectroscopic data and by chemical transformations. The absolute configuration of cacospongionolides 2a-4a was established using the modified Mosher's method. Cacospongionolide E was the most potent inhibitor toward human synovial PLA2, showing higher potency than the reference compound manoalide and exerting no signs of toxicity on human neutrophils. It showed high activity in the Artemia salina bioassay and moderate toxicity in the fish (Gambusia affinis) lethality assay.
Identification of avarol derivatives as potential antipsoriatic drugs using an in vitro model for keratinocyte growth and differentiation.
2006
Contains fulltext : 49512schalkwijk.pdf (Publisher’s version ) (Closed access) 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 …
Potential Antipsoriatic Avarol Derivatives as Antioxidants and Inhibitors of PGE2 Generation and Proliferation in the HaCaT Cell Line
2004
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…
Effects of marine 2-polyprenyl-1,4-hydroquinones on phospholipase A2 activity and some inflammatory responses.
1995
Three 2-polyprenyl-1,4-hydroquinone derivatives (2-heptaprenyl-1,4-hydroquinone: IS1, 2-octaprenyl-1,4-hydroquinone: IS2 and 2-[24-hydroxy]-octaprenyl-1,4-hydroquinone: IS3) isolated from the Mediterranean sponge Ircinia spinosula, were evaluated for effects on phospholipase A2 activity of different origin (Naja naja venom, human recombinant synovial fluid and bee venom), as well as on human neutrophil function and mouse ear oedema induced by 12-O-tetradecanoylphorbol 13-acetate (TPA). IS1 interacted minimally with these responses. In contrast, IS2 and IS3 inhibited human recombinant synovial phospholipase A2 in a concentration-dependent manner, with minor effects on the rest of the enzymes…
Inhibition of phospholipase A2 activities and some inflammatory responses by the marine product ircinin
1996
The marine product ircinin has been tested for its effects on secretory and cytosolic phospholipase A2 (PLA2) activities in vitro as well as for inhibition of cellular functions in human neutrophils and inflammatory responses in mice. Ircinin inhibited Naja naja venom, human synovial recombinant, bee venom and zymosan-injected rat air pouch PLA2 with IC50 values in the microM range, similar to those of the known inhibitor scalaradial. On the other hand, ircinin was less active on cytosolic PLA2 from human monocytes and decreased potently the release of LTB4 in human neutrophils. This marine product affected weakly human neutrophil functions like superoxide generation and degranulation. In t…
Avarol inhibits TNF-a generation and NF-kB activation in human cells and in animal models
2007
Avarol is a marine sesquiterpenoid hydroquinone with interesting pharmacological properties including anti-inflammatory and antipsoriatic effects. In the present study we evaluated the pharmacological effect of avarol on some inflammatory parameters related to the pathogenesis of psoriasis. Avarol inhibited tumor necrosis factor-alpha (TNF-alpha) generation in stimulated human monocytes (IC(50) 1 microM) and TNF-alpha-induced activation of nuclear factor-kappaB (NF-kappaB)-DNA binding in keratinocytes. In the mouse air pouch model, administration of avarol produced a dose-dependent reduction of TNF-alpha generation (ED(50) 9.2 nmol/pouch) as well as of interleukin (IL)-1beta, prostaglandin …
Reduction of hospitalizations for myocardial infarction in Italy in the COVID-19 era
2020
Abstract Aims To evaluate the impact of the COVID-19 pandemic on patient admissions to Italian cardiac care units (CCUs). Methods and Results We conducted a multicentre, observational, nationwide survey to collect data on admissions for acute myocardial infarction (AMI) at Italian CCUs throughout a 1 week period during the COVID-19 outbreak, compared with the equivalent week in 2019. We observed a 48.4% reduction in admissions for AMI compared with the equivalent week in 2019 (P < 0.001). The reduction was significant for both ST-segment elevation myocardial infarction [STEMI; 26.5%, 95% confidence interval (CI) 21.7–32.3; P = 0.009] and non-STEMI (NSTEMI; 65.1%, 95% CI 60.3–70.3; P …
Impact of Sex Differences and Diabetes on Coronary Atherosclerosis and Ischemic Heart Disease
2018
Cardiovascular diseases (CVD) including coronary artery disease (CAD) and ischemic heart disease (IHD) are the main cause of mortality in industrialized countries. Although it is well known that there is a difference in the risk of these diseases in women and men, current therapy does not consider the sexual dimorphism; i.e., differences in anatomical structures and metabolism of tissues. Here, we discuss how genetic, epigenetic, hormonal, cellular or molecular factors may explain the different CVD risk, especially in high-risk groups such as women with diabetes. We analyze whether sex may modify the effects of diabetes at risk of CAD. Finally, we discuss current diagnostic techniques in th…
"Delirium Day": a nationwide point prevalence study of delirium in older hospitalized patients using an easy standardized diagnostic tool
2016
Background To date, delirium prevalence in adult acute hospital populations has been estimated generally from pooled findings of single-center studies and/or among specific patient populations. Furthermore, the number of participants in these studies has not exceeded a few hundred. To overcome these limitations, we have determined, in a multicenter study, the prevalence of delirium over a single day among a large population of patients admitted to acute and rehabilitation hospital wards in Italy. Methods This is a point prevalence study (called “Delirium Day”) including 1867 older patients (aged 65 years or more) across 108 acute and 12 rehabilitation wards in Italian hospitals. Delirium wa…
Clinical evaluation of bempedoic acid for the treatment of hyperlipidaemia.
2021
Bempedoic acid (BA) is a novel first-in-class oral lipid-lowering therapy. BA has been approved by the European Medicinal Agency and Food and Drug Administration and has been commercialised throughout Europe since the end of 2020 as an add-on therapy in patients at high/very-high cardiovascular risk that are not at LDL-C goals with current lipid-lowering treatments. Recently, Italian lipid management experts gathered to discuss several open questions on BA characteristics and BArelated practical clinical issues. The panel permitted collection of its opinions in a ten Q&A format. Aim: The aim of this viewpoint is to discuss and answer several open questions on BA characteristics and BA-r…