Latest PUBLICATIONS

  • Cytotoxicity of Endoperoxides from the Caribbean Sponge Plakortis halichondrioides towards Sensitive and Multidrug-Resistant Leukemia Cells: Acids vs. Esters Activity Evaluation.
    Publication Date: 03/03/2017, on Marine drugs
    by Schirmeister T, Oli S, Wu H, Della Sala G, Costantino V, Seo EJ, Efferth T
    DOI: 10.3390/md15030063

    The 6-epimer of the plakortide H acid (1), along with the endoperoxides plakortide E (2), plakortin (3), and dihydroplakortin (4) have been isolated from a sample of the Caribbean sponge Plakortis halichondrioides. To perform a comparative study on the cytotoxicity towards the drug-sensitive leukemia CCRF-CEM cell line and its multi-drug resistant subline CEM/ADR5000, the acid of plakortin, namely plakortic acid (5), as well as the esters plakortide E methyl ester (6) and 6-epi-plakortide H (7) were synthesized by hydrolysis and Steglich esterification, respectively. The data obtained showed that the acids (1, 2, 5) exhibited potent cytotoxicity towards both cell lines, whereas the esters showed no activity (6, 7) or weaker activity (3, 4) compared to their corresponding acids. Plakortic acid (5) was the most promising derivative with half maximal inhibitory concentration (IC50) values of ca. 0.20 µM for both cell lines.

  • Resveratrol inhibits IL-6-induced ovarian cancer cell migration through epigenetic up-regulation of autophagy.
    Publication Date: 01/03/2017, on Molecular carcinogenesis
    by Ferraresi A, Phadngam S, Morani F, Galetto A, Alabiso O, Chiorino G, Isidoro C
    DOI: 10.1002/mc.22582

    Interleukin-6 (IL-6), a pro-inflammatory cytokine released by cancer-associated fibroblasts, has been linked to the invasive and metastatic behavior of ovarian cancer cells. Resveratrol is a naturally occurring polyphenol with the potential to inhibit cancer cell migration. Here we show that Resveratrol and IL-6 affect in an opposite manner the expression of RNA messengers and of microRNAs involved in cell locomotion and extracellular matrix remodeling associated with the invasive properties of ovarian cancer cells. Among the several potential candidates responsible for the anti-invasive effect promoted by Resveratrol, here we focused our attention on ARH-I (DIRAS3), that encodes a Ras homolog GTPase of 26-kDa. This protein is known to inhibit cell motility, and it has been shown to regulate autophagy by interacting with BECLIN 1. IL-6 down-regulated the expression of ARH-I and inhibited the formation of LC3-positive autophagic vacuoles, while promoting cell migration. On opposite, Resveratrol could counteract the IL-6 induction of cell migration in ovarian cancer cells through induction of autophagy in the cells at the migration front, which was paralleled by up-regulation of ARH-I and down-regulation of STAT3 expression. Spautin 1-mediated disruption of BECLIN 1-dependent autophagy abrogated the effects of Resveratrol, while promoting cell migration. The present data indicate that Resveratrol elicits its anti-tumor effect through epigenetic mechanisms and support its inclusion in the chemotherapy regimen for highly aggressive ovarian cancers. © 2016 Wiley Periodicals, Inc.

  • Plakofuranolactone as a Quorum Quenching Agent from the Indonesian Sponge Plakortis cf. lita.
    Publication Date: 28/02/2017, on Marine drugs
    by Costantino V, Della Sala G, Saurav K, Teta R, Bar-Shalom R, Mangoni A, Steindler L
    DOI: 10.3390/md15030059

    There is an urgent need for novel strategies to fight drug resistance and multi-drug resistance. As an alternative to the classic antibiotic therapy, attenuation of the bacteria virulence affecting their Quorum sensing (QS) system is a promising approach. Quorum sensing (QS) is a genetic regulation system that allows bacteria to communicate with each other and coordinate group behaviors. A new γ-lactone that is capable of inhibiting the LasI/R QS system, plakofuranolactone (1), was discovered in the extract of the marine sponge Plakortis cf. lita, and its structure, including absolute configuration, was determined by NMR spectroscopy, MS spectrometry, and quantum-mechanical prediction of optical rotation. The quorum quenching activity of plakofuranolactone was evaluated using reporter gene assays for long- and short-chain signals (E. coli pSB1075, E. coli pSB401, and C. violeaceum CV026) and was confirmed by measuring the total protease activity (a virulence factor which is under control of the LasI/R system) of the wild-type P. aeruginosa PAO1. Further research will be pursued to assess the potential of plakofuranolactone as a new antivirulence lead compound and a chemical tool to increase the knowledge in this field.

  • X-ray Structure of the Carboplatin-Loaded Apo-Ferritin Nanocage.
    Publication Date: 28/02/2017, on ACS medicinal chemistry letters
    by Pontillo N, Ferraro G, Helliwell JR, Amoresano A, Merlino A
    DOI: 10.1021/acsmedchemlett.7b00025

    The second-generation Pt anticancer agent carboplatin (CBDCA) was encapsulated within the apo horse spleen ferritin (AFt) nanocage, and the X-ray structure of the drug-loaded protein was refined at 1.49 Å resolution. Two Pt binding sites, different from the one observed in the cisplatin-encapsulated AFt, were identified in Ft subunits by inspection of anomalous electron density maps at two wavelengths and difference Fourier electron density maps, which provide the necessary sensitivity to discriminate between Pt from CBDCA and Cd ions that are present in the crystallization conditions. Pt centers coordinate to the NE2 atom of His49 and to the NE2 atom of His132, both on the inner surface of the Ft nanocage.

  • tDCS reactivation of dormant adaptation circuits.
    Publication Date: 24/02/2017, on Cortex; a journal devoted to the study of the nervous system and behavior
    by Panico F, Jacquin-Courtois S, Di Marco J, Perrin C, Trojano L, Rossetti Y
    DOI: 10.1016/j.cortex.2017.02.003

  • Quorum Sensing Inhibitors from the Sea Discovered Using Bacterial N-acyl-homoserine Lactone-Based Biosensors.
    Publication Date: 23/02/2017, on Marine drugs
    by Saurav K, Costantino V, Venturi V, Steindler L
    DOI: 10.3390/md15030053

    Marine natural products with antibiotic activity have been a rich source of drug discovery; however, the emergence of antibiotic-resistant bacterial strains has turned attention towards the discovery of alternative innovative strategies to combat pathogens. In many pathogenic bacteria, the expression of virulence factors is under the regulation of quorum sensing (QS). QS inhibitors (QSIs) present a promising alternative or potential synergistic treatment since they disrupt the signaling pathway used for intra- and interspecies coordination of expression of virulence factors. This review covers the set of molecules showing QSI activity that were isolated from marine organisms, including plants (algae), animals (sponges, cnidarians, and bryozoans), and microorganisms (bacteria, fungi, and cyanobacteria). The compounds found and the methods used for their isolation are the emphasis of this review.

  • Butyrate Regulates Liver Mitochondrial Function, Efficiency, and Dynamic, in Insulin Resistant Obese Mice.
    Publication Date: 21/02/2017, on Diabetes
    by Mollica MP, Raso GM, Cavaliere G, Trinchese G, De Filippo C, Aceto S, Prisco M, Pirozzi C, Di Guida F, Lama A, Crispino M, Tronino D, Di Vaio P, Canani RB, Calignano A, Meli R
    DOI: 10.2337/db16-0924

    Fatty liver, oxidative stress, and mitochondrial dysfunction are key pathophysiological features of insulin resistance and obesity. Butyrate, produced by fermentation in the large intestine by gut microbiota, and its synthetic derivative, the N-(1-carbamoyl-2-phenyl-ethyl) butyramide, FBA, have been demonstrated to be protective against insulin resistance and fatty liver.Here, hepatic mitochondria were identified as the main target of the beneficial effect of both butyrate-based compounds in reverting insulin resistance and fat accumulation in diet induced obese mice. In particular, butyrate and FBA improved respiratory capacity and fatty acid oxidation, activating AMPK-ACC pathway, and promoted inefficient metabolism, as shown by the increase in proton leak. Consistently, both treatments increase utilization of substrates, especially fatty acids, leading to the reduction of intracellular lipid accumulation and oxidative stress. Finally, the shift of mitochondrial dynamic toward fusion by butyrate and FBA resulting in the improvement not only of mitochondrial cell energy metabolism but also of glucose homeostasis.In conclusion, butyrate and its more palatable synthetic derivative, FBA, modulating mitochondrial function, efficiency and dynamic, can be considered a new therapeutic strategy to counteract obesity and insulin resistance.

  • Formyl peptide receptor 1 suppresses gastric cancer angiogenesis and growth by exploiting inflammation resolution pathways.
    Publication Date: 21/02/2017, on Oncoimmunology
    by Prevete N, Liotti F, Illiano A, Amoresano A, Pucci P, de Paulis A, Melillo RM
    DOI: 10.1080/2162402X.2017.1293213

    Chronic inflammation can result from inadequate engagement of resolution mechanisms, mainly accomplished by specialized pro-resolving mediators (SPMs) arising from the metabolic activity of lipoxygenases (ALOX5/15) on ω-6 or ω-3 essential polyunsaturated fatty acids (PUFA). We previously demonstrated that formyl peptide receptor 1 (FPR1) suppresses gastric cancer (GC) by inhibiting its inflammatory/angiogenic potential. In this study, we asked whether FPR1 exploits inflammation resolution pathways to suppress GC angiogenesis and growth. Here, we demonstrate that genetic or pharmacologic modulation of FPR1 in GC cells regulated ALOX5/15 expression and production of the SPMs Resolvin D1 (RvD1) and Lipoxin B4 (LXB4). SPM treatment of GC cells abated their angiogenic potential. Genetic deletion of ALOX15 or of the RvD1 receptor GPR32 increased the angiogenic and tumorigenic activity of GC cells thereby mimicking FPR1 loss. Deletion/inhibition of ALOX5/15 or GPR32 blocked FPR1-mediated anti-angiogenic activities, indicating that ALOX5/15 and GPR32 are required for FPR1's pro-resolving action. An ω-3- or ω-6-enriched diet enforced SPM endogenous production in mice and inhibited growth of shFPR1 GC xenografts by suppressing their angiogenic activity. These data implicate that FPR1 and/or pro-resolving pathway components might be used as risk/prognostic markers for GC; ω-6/3-enriched diets, and targeting FPR1 or SPM machinery may be exploited for GC management.

  • Integrin-dependent cell adhesion to neutrophil extracellular traps through engagement of fibronectin in neutrophil-like cells.
    Publication Date: 06/02/2017, on PloS one
    by Monti M, Iommelli F, De Rosa V, Carriero MV, Miceli R, Camerlingo R, Di Minno G, Del Vecchio S
    DOI: 10.1371/journal.pone.0171362

    Neutrophil extracellular traps (NETs), originally recognized as a host defense mechanism, were reported to promote thrombosis and metastatic dissemination of cancer cells. Here we tested the role of integrins α5β1 and ανβ3 in the adhesion of cancer cells to NETs. Neutrophil-like cells stimulated with calcium ionophore (A23187) were used as a stable source of cell-free NETs-enriched suspensions. Using NETs as an adhesion substrate, two human K562 cell lines, differentially expressing α5β1 and ανβ3 integrins, were subjected to adhesion assays in the presence or absence of DNAse 1, blocking antibodies against α5β1 or ανβ3, alone or in combination with DNAse 1, and Proteinase K. As expected DNAse 1 treatment strongly inhibited adhesion of both cell lines to NETs. An equivalent significant reduction of cell adhesion to NETs was obtained after treatment of cells with blocking antibodies against α5β1 or ανβ3 indicating that both integrins were able to mediate cell adhesion to NETs. Furthermore, the combination of DNAse 1 and anti-integrin antibody treatment almost completely blocked cell adhesion. Western blot analysis and immunoprecipitation experiments showed a dose-dependent increase of fibronectin levels in samples from stimulated neutrophil-like cells and a direct or indirect interaction of fibronectin with histone H3. Finally, co-immunolocalization studies with confocal microscopy showed that fibronectin and citrullinated histone H3 co-localize inside the web-structure of NETs. In conclusion, our study showed that α5β1 and ανβ3 integrins mediate cell adhesion to NETs by binding to their common substrate fibronectin. Therefore, in addition to mechanical trapping and aspecific adsorption of different cell types driven by DNA/histone complexes, NETs may provide specific binding sites for integrin-mediated cell adhesion of neutrophils, platelets, endothelial and cancer cells thus promoting intimate interactions among these cells.

  • Alterations in the carnitine cycle in a mouse model of Rett syndrome.
    Publication Date: 02/02/2017, on Scientific reports
    by Mucerino S, Di Salle A, Alessio N, Margarucci S, Nicolai R, Melone MA, Galderisi U, Peluso G
    DOI: 10.1038/srep41824

    Rett syndrome (RTT) is a neurodevelopmental disease that leads to intellectual deficit, motor disability, epilepsy and increased risk of sudden death. Although in up to 95% of cases this disease is caused by de novo loss-of-function mutations in the X-linked methyl-CpG binding protein 2 gene, it is a multisystem disease associated also with mitochondrial metabolic imbalance. In addition, the presence of long QT intervals (LQT) on the patients' electrocardiograms has been associated with the development of ventricular tachyarrhythmias and sudden death. In the attempt to shed light on the mechanism underlying heart failure in RTT, we investigated the contribution of the carnitine cycle to the onset of mitochondrial dysfunction in the cardiac tissues of two subgroups of RTT mice, namely Mecp2(+/-) NQTc and Mecp2(+/-) LQTc mice, that have a normal and an LQT interval, respectively. We found that carnitine palmitoyltransferase 1 A/B and carnitine acylcarnitine translocase were significantly upregulated at mRNA and protein level in the heart of Mecp2(+/-) mice. Moreover, the carnitine system was imbalanced in Mecp2(+/-) LQTc mice due to decreased carnitine acylcarnitine transferase expression. By causing accumulation of intramitochondrial acylcarnitines, this imbalance exacerbated incomplete fatty acid oxidation, which, in turn, could contribute to mitochondrial overload and sudden death.

  • Mesenchymal stromal cells having inactivated RB1 survive following low irradiation and accumulate damaged DNA: Hints for side effects following radiotherapy.
    Publication Date: 01/02/2017, on Cell cycle (Georgetown, Tex.)
    by Alessio N, Capasso S, Di Bernardo G, Cappabianca S, Casale F, Calarco A, Cipollaro M, Peluso G, Galderisi U
    DOI: 10.1080/15384101.2016.1175798

    Following radiotherapy, bone sarcomas account for a significant percentage of recurring tumors. This risk is further increased in patients with hereditary retinoblastoma that undergo radiotherapy. We analyzed the effect of low and medium dose radiation on mesenchymal stromal cells (MSCs) with inactivated RB1 gene to gain insights on the molecular mechanisms that can induce second malignant neoplasm in cancer survivors. MSC cultures contain subpopulations of mesenchymal stem cells and committed progenitors that can differentiate into mesodermal derivatives: adipocytes, chondrocytes, and osteocytes. These stem cells and committed osteoblast precursors are the cell of origin in osteosarcoma, and RB1 gene mutations have a strong role in its pathogenesis. Following 40 and 2000 mGy X-ray exposure, MSCs with inactivated RB1 do not proliferate and accumulate high levels of unrepaired DNA as detected by persistence of gamma-H2AX foci. In samples with inactivated RB1 the radiation treatment did not increase apoptosis, necrosis or senescence versus untreated cells. Following radiation, CFU analysis showed a discrete number of cells with clonogenic capacity in cultures with silenced RB1. We extended our analysis to the other members of retinoblastoma gene family: RB2/P130 and P107. Also in the MSCs with silenced RB2/P130 and P107 we detected the presence of cells with unrepaired DNA following X-ray irradiation. Cells with unrepaired DNA may represent a reservoir of cells that may undergo neoplastic transformation. Our study suggests that, following radiotherapy, cancer patients with mutations of retinoblastoma genes may be under strict controls to evaluate onset of secondary neoplasms following radiotherapy.

  • Tyramine Pathways in Citrus Plant Defense: Glycoconjugates of Tyramine and Its N-Methylated Derivatives.
    Publication Date: 01/02/2017, on Journal of agricultural and food chemistry
    by Servillo L, Castaldo D, Giovane A, Casale R, D'Onofrio N, Cautela D, Balestrieri ML
    DOI: 10.1021/acs.jafc.6b04423

    Glucosylated forms of tyramine and some of its N-methylated derivatives are here reported for the first time to occur in Citrus genus plants. The compounds tyramine-O-β-d-glucoside, N-methyltyramine-O-β-d-glucoside, and N,N-dimethyltyramine-O-β-d-glucoside were detected in juice and leaves of sweet orange, bitter orange, bergamot, citron, lemon, mandarin, and pomelo. The compounds were identified by mass spectrometric analysis, enzymatic synthesis, and comparison with extracts of Stapelia hirsuta L., a plant belonging to the Apocynaceae family in which N,N-dimethyltyramine-O-β-d-glucoside was identified by others. Interestingly, in Stapelia hirsuta we discovered also tyramine-O-β-d-glucoside, N-methyltyramine-O-β-d-glucoside, and the tyramine metabolite, N,N,N-trimethyltyramine-O-β-glucoside. However, the latter tyramine metabolite, never described before, was not detected in any of the Citrus plants included in this study. The presence of N-methylated tyramine derivatives and their glucosylated forms in Citrus plants, together with octopamine and synephrine, also deriving from tyramine, supports the hypothesis of specific biosynthetic pathways of adrenergic compounds aimed to defend against biotic stress.

  • Incretin treatment and atherosclerotic plaque stability: Role of adiponectin/APPL1 signaling pathway.
    Publication Date: 01/02/2017, on Journal of diabetes and its complications
    by Barbieri M, Marfella R, Esposito A, Rizzo MR, Angellotti E, Mauro C, Siniscalchi M, Chirico F, Caiazzo P, Furbatto F, Bellis A, D'Onofrio N, Vitiello M, Ferraraccio F, Paolisso G, Balestrieri ML
    DOI: 10.1016/j.jdiacomp.2016.10.001

    Glucagon like peptide 1 (GLP-1) analogues and dipeptidyl peptidase IV (DPP-4) inhibitors reduce atherosclerosis progression in type 2 diabetes mellitus (T2DM) patients and are associated with morphological and compositional characteristics of stable plaque phenotype. GLP-1 promotes the secretion of adiponectin which exerts anti-inflammatory effects through the adaptor protein PH domain and leucine zipper containing 1 (APPL1). The potential role of APPL1 expression in the evolution of atherosclerotic plaque in TDM2 patients has not previously evaluated.

  • Hot spot mapping of protein surfaces with TEMPOL: Bovine pancreatic RNase A as a model system.
    Publication Date: 01/02/2017, on Biochimica et biophysica acta
    by Niccolai N, Morandi E, Gardini S, Costabile V, Spadaccini R, Crescenzi O, Picone D, Spiga O, Bernini A
    DOI: 10.1016/j.bbapap.2016.11.014

    TEMPOL spin-label has been used to identify surface exposure of protein nuclei from NMR analysis of the induced paramagnetic relaxation enhancements (PRE). The absence of linear dependence between atom depths and observed PRE reveals that specific mechanisms drive the approach of the paramagnet to the protein surface. RNase A represents a unique protein system to explore the fine details of the information offered by TEMPOL induced PRE, due to the abundance of previous results, obtained in solution and in the crystal, dealing with surface dynamics behavior of this protein. MD simulations in explicit solvent have been performed, also in the presence of TEMPOL, in order to delineate the role of intermolecular hydrogen bonds (HB) on PRE extents. Comparison of our results with the ones obtained from multiple solvent crystal structure (MSCS) studies yields information on the specificities that these two techniques have for characterizing protein-ligand interactions, a fundamental step in the development of reliable surface druggability predictors.

  • Genetic characterization of Italian patients with Bardet-Biedl syndrome and correlation to ocular, renal and audio-vestibular phenotype: identification of eleven novel pathogenic sequence variants.
    Publication Date: 01/02/2017, on BMC medical genetics
    by Esposito G, Testa F, Zacchia M, Crispo AA, Di Iorio V, Capolongo G, Rinaldi L, D'Antonio M, Fioretti T, Iadicicco P, Rossi S, Franzè A, Marciano E, Capasso G, Simonelli F, Salvatore F
    DOI: 10.1186/s12881-017-0372-0

    Bardet-Biedl syndrome (BBS) is a rare genetic disorder that features retinal degeneration, obesity, polydactyly, learning disabilities and renal abnormalities. The diagnosis is often missed at birth, the median age at diagnosis being 9 years. In the attempt to shed light on BBS and improve its diagnosis and treatment, we evaluated the genotype-phenotype relationship in patients with a molecular diagnosis of BBS.