Controlled Pore Glass-based oligonucleotide affinity support: towards High Throughput Screening methods for the identification of conformation-selective G-quadruplex ligands.
Publication Date: 07/11/2018, on Analytica chimica acta
by Platella C, Musumeci D, Arciello A, Doria F, Freccero M, Randazzo A, Amato J, Pagano B, Montesarchio D
Target selectivity is one of the main challenges in the search for small molecules able to act as effective and non-toxic anticancer and/or antiviral drugs. To achieve this goal, handy, rapid and reliable High Throughput Screening methodologies are needed. We here describe a novel functionalization for the solid phase synthesis of oligonucleotides on Controlled Pore Glass, including a flexible hexaethylene glycol spacer linking the first nucleoside through the nucleobase via a covalent bond stable to the final deprotection step. This allowed us preparing fully deprotected oligonucleotides still covalently attached to their supports. In detail, on this support we performed both the on-line synthesis of different secondary structure-forming oligonucleotides and the affinity chromatography-based screenings of conformation-selective G-quadruplex ligands. By using a fluorescent core-extended naphthalene diimide with different emitting response upon binding to sequences folding into G-quadruplexes of different topologies, we have been able to discriminate not only G-quadruplex vs. duplex DNA structures, but also different G-quadruplex conformations on the glass beads by confocal microscopy.
Ruminant meat and milk contain δ-valerobetaine, another precursor of trimethylamine N-oxide (TMAO) like γ-butyrobetaine.
Publication Date: 15/09/2018, on Food chemistry
by Servillo L, D'Onofrio N, Giovane A, Casale R, Cautela D, Castaldo D, Iannaccone F, Neglia G, Campanile G, Balestrieri ML
Quaternary ammonium compounds containing N-trimethylamino moiety, such as choline derivatives and carnitine, abundant in meat and dairy products, are metabolic precursors of trimethylamine (TMA). A similar fate is reported for N-trimethyllysine and γ-butyrobetaine. With the aim at investigating the metabolic profile of such metabolites in most employed animal dietary sources, HPLC-ESI-MS/MS analyses on ruminant and non-ruminant milk and meat were performed. Results demonstrate, for the first time, the presence of δ-valerobetaine, occurring at levels higher than γ-butyrobetaine in all ruminant samples compared to non-ruminants. Demonstration of δ-valerobetaine metabolic origin, surprisingly, showed that it originates from rumen through the transformation of dietary N-trimethyllysine. These results highlight our previous findings showing the ubiquity of free N-trimethyllysine in vegetable kingdom. Furthermore, δ-valerobetaine, similarly to γ-butyrobetaine, can be degraded by host gut microbiota producing TMA, precursor of the proatherogenic trimethylamine N-oxide (TMAO), unveiling its possible role in the biosynthetic route of TMAO.
Dihydroartemisinin induces apoptosis and autophagy-dependent cell death in cholangiocarcinoma through a DAPK1-BECLIN1 pathway.
Publication Date: 22/08/2018, on Molecular carcinogenesis
by Thongchot S, Vidoni C, Ferraresi A, Loilome W, Yongvanit P, Namwat N, Isidoro C
Cholangiocarcinoma (CCA) is a very aggressive cancer arising from the malignant transformation of cholangiocytes. Intrahepatic CCA is associated with reactive inflammation and intense fibrosis of the hepatobiliary tract. Dihydroartemisinin (DHA), the active compound found in Artemisia annua, has been shown to possess anti-tumor activity in a variety of human cancers, including hepatoma. Here, we tested the ability of DHA to specifically kill CCA cells and have investigated the underlying mechanisms. DHA induced both apoptosis and autophagy-dependent caspase-independent cell death in many CCA cell lines, while being slightly toxic to immortalized cholangiocytes. DHA induced the expression of many apoptosis- and autophagy-related genes in CCA cells. In particular, it greatly induced the expression of DAPK1, and reduced the interaction of BECLIN1 with BCL-2 while promoting its interaction with PI3KC3. Genetic silencing of DAPK1 prevented DHA-induced autophagy. Pharmacologic and genetic inhibition of BECLIN1 function prevented autophagy and cell death induced by DHA in CCA cells. These data unravel a novel pathway of DHA cancer toxicity and open the possibility to introduce DHA in the therapeutic regimen for the treatment of CCA. This article is protected by copyright. All rights reserved.
Isolation of Smenopyrone, a Bis-γ-Pyrone Polypropionate from the Caribbean Sponge <i>Smenospongia aurea</i>.
Publication Date: 17/08/2018, on Marine drugs
by Esposito G, Teta R, Della Sala G, Pawlik JR, Mangoni A, Costantino V
The organic extract of the Caribbean sponge has been shown to contain an array of novel chlorinated secondary metabolites derived from a mixed PKS-NRPS biogenetic route such as the smenamides. In this paper, we report the presence of a biogenetically different compound known as smenopyrone, which is a polypropionate containing two γ-pyrone rings. The structure of smenopyrone including its relative and absolute stereochemistry was determined by spectroscopic analysis (NMR, MS, ECD) and supported by a comparison with model compounds from research studies. Pyrone polypropionates are unprecedented in marine sponges but are commonly found in marine mollusks where their biosynthesis by symbiotic bacteria has been hypothesized and at least in one case demonstrated. Since pyrones have recently been recognized as bacterial signaling molecules, we speculate that smenopyrone could mediate inter-kingdom chemical communication between and its symbiotic bacteria.
Minimally Invasive and Portable Method for the Identification of Proteins in Ancient Paintings.
Publication Date: 15/08/2018, on Analytical chemistry
by Cicatiello P, Ntasi G, Rossi M, Marino G, Giardina P, Birolo L
A novel method for the analysis of proteinaceous materials present on painted surfaces was developed by taking advantage of the adhesive ability of some fungal proteins which can form a stable and homogeneous layer on flexible transparency sheets able to capture trypsin in a fully active form. We demonstrated that the bioactive sheets were able to efficiently digest proteins, present as such, on surfaces of painted tests and historical samples, releasing peptides that can allow an easy and confident identification of the proteinaceous binders by standard bottom-up proteomic approach. By this method there is no need: (i) to transport the artifacts and (ii) to remove, even at micro level, a sample from the object. The ingenuity of the method lies in the easily accommodated sampling coupled with a minimal invasiveness.
Novel use of Evolved Gas Analysis/Mass Spectrometry to identify the earliest organic binder in Aegean style wall paintings from Tel Kabri, Israel, dated to the late 18th C. B.C.E.
Publication Date: 10/08/2018, on Angewandte Chemie (International ed. in English)
by Linn R, Bonaduce I, Ntasi G, Birolo L, Yasur-Landau A, Cline E, Nevin A, Lluveras-Tenorio A
An organic binder was identified in the painted fragments from the Canaanite palace of Tel Kabri, Israel. Recently dated to the late 18th C. B.C.E. by 14C, Tel Kabri is the most ancient of the Eastern Mediterranean sites in which Aegean style paintings have been found. The application of pigments was suspected to be using an organic binding medium, particularly for the Egyptian Blue pigment. Samples of blue paint were examined using Evolved Gas Analysis/Mass Spectrometry (EGA-MS) in order to overcome the analytical challenge imposed by highly degraded aged proteinaceous materials. Egg was identified as the binder based on the presence of Hexadecanonitrile and octadecanonitrile confirming the use of a secco painting technique. Lysozyme C from Gallus gallus was detected by proteomics analysis, confirming the presence of egg. To the authors' knowledge, this is the earliest use of egg as a binder in Aegean style wall paintings.
Neutrophil Extracellular Traps as an Adhesion Substrate for Different Tumor Cells Expressing RGD-Binding Integrins.
Publication Date: 09/08/2018, on International journal of molecular sciences
by Monti M, De Rosa V, Iommelli F, Carriero MV, Terlizzi C, Camerlingo R, Belli S, Fonti R, Di Minno G, Del Vecchio S
Neutrophil extracellular traps (NETs), in addition to their function as a host defense mechanism, play a relevant role in thrombus formation and metastatic dissemination of cancer cells. Here we screened different cancer cell lines endogenously expressing a variety of integrins for their ability to bind to NETs. To this end, we used NETs isolated from neutrophil-like cells as a substrate for adhesion assays of HT1080, U-87 MG, H1975, DU 145, PC-3 and A-431 cells. Levels of α5, αIIb, αv, β1, β3 and β5 chains were determined by western blot analysis in all cell lines and levels of whole integrins on the plasma membrane were assessed by fluorescence-activated cell sorting (FACS) analysis. We found that high levels of α5β1, αvβ3 and αvβ5 enhance cell adhesion to NETs, whereas low expression of α5β1 prevents cell attachment to NETs. Excess of cyclic RGD peptide inhibited cell adhesion to NETs by competing with fibronectin within NETs. The maximal reduction of such adhesion was similar to that obtained by DNase 1 treatment causing DNA degradation. Our findings indicate that NETs from neutrophil-like cells may be used as a substrate for large screening of the adhesion properties of cancer cells expressing a variety of RGD-binding integrins.
HMGB1 binds to the KRAS promoter G-quadruplex: a new player in oncogene transcriptional regulation?
Publication Date: 06/08/2018, on Chemical communications (Cambridge, England)
by Amato J, Madanayake TW, Iaccarino N, Novellino E, Randazzo A, Hurley LH, Pagano B
This communication reports on a possible distinct role of HMGB1 protein. Biophysical studies revealed that HMGB1 binds and stabilizes the G-quadruplex of the KRAS promoter element that is responsible for most of the transcriptional activity. Biological data showed that inhibition of HMGB1 increases KRAS expression. These results suggest that HMGB1 could play a role in the gene transcriptional regulation via the functional recognition of the G-quadruplex.
Bullying at Workplace and Brain-Imaging Correlates.
Publication Date: 04/08/2018, on Journal of clinical medicine
by Nolfe G, Cirillo M, Iavarone A, Negro A, Garofalo E, Cotena A, Lazazzara M, Zontini G, Cirillo S
The relationship between psychosocial stress at work and mental health outcome is well-known. Brain-imaging studies hypothesize morphological brain modifications connected to work-related stress. To our knowledge this is the first study describing the link between work characteristics and brain imaging in a sample of work-related psychiatric patients assessed according to standardized clinical and diagnostic criteria. The aims of the study are: (1) to evaluate hippocampal and whole brain volumes in work-related psychiatric disturbances; (2) to verify the relationship between brain changes and the anxious and/or depressive symptoms; (3) to observe the relationship between the brain changes and the degree of the bullying at workplace. The hippocampus and whole brain volumes of 23 patients with work-related adjustment-disorders were compared with 15 controls by means of MRI. MR images highlight a smaller hippocampal volume in patients compared with controls. Significant reduction in the patients' gray matter was found in three brain areas: right inferior temporal gyrus, left cuneus, left inferior occipital gyrus. The reduction of the hippocampi volumes was related to work distress and, above all, to bullying at workplace. The results confirm that the morphological brain abnormalities could be involved in work-related psychiatric disturbances.
Visual pursuit of one's own face in disorders of consciousness: a quantitative analysis.
Publication Date: 30/07/2018, on Brain injury
by Trojano L, Moretta P, Masotta O, Loreto V, Estraneo A
Eye behaviour is important to distinguish minimally conscious state (MCS) from vegetative state (VS).
Determinants of therapy switch in multiple sclerosis treatment-naïve patients: A real-life study.
Publication Date: 25/07/2018, on Multiple sclerosis (Houndmills, Basingstoke, England)
by Saccà F, Lanzillo R, Signori A, Maniscalco GT, Signoriello E, Lo Fermo S, Repice A, Annovazzi P, Baroncini D, Clerico M, Binello E, Cerqua R, Mataluni G, Bonavita S, Lavorgna L, Zarbo IR, Laroni A, Rossi S, Pareja Gutierrez L, La Gioia S, Frigeni B, Barcella V, Frau J, Cocco E, Fenu G, Torri Clerici V, Sartori A, Rasia S, Cordioli C, Di Sapio A, Pontecorvo S, Grasso R, Barrilà C, Russo CV, Esposito S, Ippolito D, Bovis F, Gallo F, Sormani MP,
With many options now available, first therapy choice is challenging in multiple sclerosis (MS) and depends mainly on neurologist and patient preferences.
Organization of GPI-anchored proteins at the cell surface and its physiopathological relevance.
Publication Date: 24/07/2018, on Critical reviews in biochemistry and molecular biology
by Lebreton S, Zurzolo C, Paladino S
Glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs) are a class of proteins attached to the extracellular leaflet of the plasma membrane via a post-translational modification, the glycolipid anchor. The presence of both glycolipid anchor and protein portion confers them unique features. GPI-APs are expressed in all eukaryotes, from fungi to plants and animals. They display very diverse functions ranging from enzymatic activity, signaling, cell adhesion, cell wall metabolism, neuritogenesis, and immune response. Likewise other plasma membrane proteins, the spatio-temporal organization of GPI-APs is critical for their biological activities in physiological conditions. In this review, we will summarize the latest findings on plasma membrane organization of GPI-APs and the mechanism of its regulation in different cell types. We will also examine the involvement of specific GPI-APs namely the prion protein PrP, the Folate Receptor alpha and the urokinase plasminogen activator receptor in human diseases focusing on neurodegenerative diseases and cancer.
Carnitine Precursors and Short-Chain Acylcarnitines in Water Buffalo Milk.
Publication Date: 24/07/2018, on Journal of agricultural and food chemistry
by Servillo L, D'Onofrio N, Neglia G, Casale R, Cautela D, Marrelli M, Limone A, Campanile G, Balestrieri ML
Ruminants' milk contains δ-valerobetaine originating from rumen through the transformation of dietary N-trimethyllysine. Among ruminant's milk, the occurrence of δ-valerobetaine, along with carnitine precursors and metabolites, has not been investigated in buffalo milk, the second most worldwide consumed milk, well-known for its nutritional value. HPLC-ESI-MS/MS analyses of bulk milk revealed that the Italian Mediterranean buffalo milk contains δ-valerobetaine at levels higher than those in bovine milk. Importantly, we detected also γ-butyrobetaine, the l-carnitine precursor, never described so far in any milk. Of interest, buffalo milk shows higher levels of acetylcarnitine, propionylcarnitine, butyrylcarnitine, isobutyrylcarnitine, and 3-methylbutyrylcarnitine (isovalerylcarnitine) than cow milk. Moreover, buffalo milk shows isobutyrylcarnitine and butyrylcarnitine at a 1-to-1 molar ratio, while in cow's milk this ratio is 5 to 1. Results indicate a peculiar short-chain acylcarnitine profile characterizing buffalo milk, widening the current knowledge about its composition and nutritional value.
Structural differences between toxic and nontoxic HypF-N oligomers.
Publication Date: 18/07/2018, on Chemical communications (Cambridge, England)
by Capitini C, Patel JR, Natalello A, D'Andrea C, Relini A, Jarvis JA, Birolo L, Peduzzo A, Vendruscolo M, Matteini P, Dobson CM, De Simone A, Chiti F
We have studied two misfolded oligomeric forms of the protein HypF-N, which show similar morphologies but very different toxicities. We measured over 80 intermolecular distance-dependent parameters for each oligomer type using FRET, in conjunction with solution- and solid-state NMR and other biophysical techniques. The results indicate that the formation of a highly organised hydrogen bonded core in the toxic oligomers results in the exposure of a larger number of hydrophobic residues than in the nontoxic species, causing the former to form aberrant interactions with cellular components.
Usher syndrome and color vision.
Publication Date: 17/07/2018, on Current eye research
by Kurtenbach A, Hahn G, Kernstock C, Hipp S, Zobor D, Stingl K, Kohl S, Bonnet C, Mohand-Saïd S, Sliesoraityte I, Sahel JA, Audo I, Fakin A, Hawlina M, Testa F, Simonelli F, Petit C, Zrenner E
Purpose The aim of this study is to report on the results of color vision testing in a European cohort of patients with Usher syndrome (USH). We describe the results in relation to Usher type (USH1, USH2), age and visual acuity. Methods and Methods The color vision of 220 genetically confirmed adult USH patients, aged 18-70 years, was analyzed with one of 3 methods: the Farnsworth D-15 Dichotomous test (D-15) along with the Lanthony desaturated 15 Hue tests (D-15d), the Roth 28-Hue test, or the Ishihara 14-plate test. Visual acuity was measured with either the ETDRS or the SNELLEN charts. The Confusion index, the Selectivity index and the Confusion angle were calculated for the panel tests and used for analysis. The number of plates that could not be read were analyzed for the Ishihara test. Results For the panel tests, the degree of color loss (Confusion index) is similar in both subtypes of USH, but the polarization of error scores (Selectivity index) is significantly lower in USH1 than USH2, showing more diffuse errors than those found in USH2. There is no significant correlation between logMAR visual acuity and the Confusion or the Selectivity indices. Additionally, we find a significant correlation between patient age and the degree and the polarity of the loss only in USH2. There was no difference between USH1 and USH2 in the results of the Ishihara test. Conclusions The examination of color vision in patients with USH, shows a significant difference in the pattern of color vision loss in USH1 and USH2 patients, but not in the severity of the loss. In USH2 we find a correlation between patient age and the degree and the polarity of the loss. These results may be due to differences in the pathogenesis of retinal dystrophy in USH1 and USH2.