Publications by authors named "Annamaria Naggi"

Introduction: Heparins, naturally occurring glycosaminoglycans, are widely used for thrombosis prevention. Upon application as anticoagulants in cancer patients, heparins were found to possess additional antitumor activities. Ectonucleotidases have recently been proposed as novel targets for cancer immunotherapy.

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Several publications have recently proposed NMR spectroscopy to evaluate the critical quality attributes (CQA) of pentosan polysulfate sodium (PPS), the active ingredient of Elmiron™ approved to treat interstitial cystitis. PPS is a polymer of sulfated β(1-4)-d-xylopyranose residues randomly substituted by 4-O-methyl-glucopyranosyluronic acid, containing, beyond the main xylose-2,3-O-disulfate repetitive unit, some minor residues that can be marker of both the starting material and preparation process. In the present study we assigned some previously unknown cross-peaks in H-C HSQC NMR of PPS related to its minor sequences adding additional details to its CQA.

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Objective:  Danaparoid sodium is a biopolymeric complex drug composed of the most abundant heparan sulfate (HS) followed in descending order by dermatan sulfate (DS) and chondroitin sulfate (CS). This composite nature explains its peculiar antithrombotic and anticoagulant properties and make it particularly advantageous when the risk of heparin-induced thrombocytopenia occurs. A specific control of the danaparoid composition is required by the Ph.

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In renal transplantation, chronic transplant dysfunction (CTD) is associated with increased PCSK9 and dyslipidemia. PCSK9 is an enzyme that increases plasma cholesterol levels by downregulating LDLR expression. We recently showed increased PCSK9-syndecan-1 interaction in conditions of proteinuria and renal function loss.

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Two years since the outbreak of the novel coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic, there remain few clinically effective drugs to complement vaccines. One is the anticoagulant, heparin, which in 2004 was found able to inhibit invasion of SARS-CoV (CoV-1) and which has been employed during the current pandemic to prevent thromboembolic complications and moderate potentially damaging inflammation. Heparin has also been shown experimentally to inhibit SARS-CoV-2 attachment and infection in susceptible cells.

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During the manufacture of pharmaceutical heparin, a range of treatments are applied to sanitize, decolourise and reduce the pyrogenic properties of the samples. The structural effects of bleaching, an oxidative process, are examined. Among H and C NMR signals ascribable to the tetrasaccharide linkage region of heparin, samples of porcine mucosal heparin frequently display characteristic signals at chemical shift values of 4.

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Enoxaparin, widely used antithrombotic drug, is a polydisperse glycosaminoglycan with highly microheterogeneous structure dictated by both parent heparin heterogeneity and depolymerization conditions. While the process-related modifications of internal and terminal sequences of enoxaparin have been extensively studied, very little is known about the authentic non-reducing ends (NRE). In the present study a multi-step isolation and thorough structural elucidation by NMR and LC/MS allowed to identify 16 saturated tetramers along with 23 unsaturated ones in the complex enoxaparin tetrasaccharide fraction.

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Background: The bone morphogenetic protein 6 (BMP6) is a crucial inducer of hepcidin, the peptide hormone that regulates the iron availability in our body. Hepcidin expression is influenced by hepatic heparan sulfate (HS) and by heparin administration, suggesting BMP6 interaction with heparin/HS. The BMP2/4 subfamily has been deeply characterized to have a N-terminal heparin/HS binding domain (HBD), whose basic residues contact the sulfate groups on heparin and HS.

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Tetra-tert-butyl-3-chloro-1-hydroxydistannoxane has been found to selectively cleave with high efficiency primary acetates on complex oligosaccharides containing esterified l-iduronic acid and bearing an anomeric acetate. This tin based catalyst was found much more effective than magnesium methoxide to carry out selective deacetylation.

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It is well-known that heparin and other glycosaminoglycans (GAGs) inhibit complement activation. It is however not known whether fractionation and/or modification of GAGs might deliver pathway-specific inhibition of the complement system. Therefore, we evaluated a library of GAGs and their derivatives for their functional pathway specific complement inhibition, including the MASP-specific C4 deposition assay.

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The chapter will review early and more recent seminal contributions to the discovery and characterization of heparanase and non-anticoagulant heparins inhibiting its peculiar enzymatic activity. Indeed, heparanase displays a unique versatility in degrading heparan sulfate chains of several proteoglycans expressed in all mammalian cells. This endo-β-D-glucuronidase is overexpressed in cancer, inflammation, diabetes, atherosclerosis, nephropathies and other pathologies.

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Tumor cell-platelet interactions are regarded as an initial crucial step in hematogenous metastasis. Platelets protect tumor cells from immune surveillance in the blood, mediate vascular arrest, facilitate tumor extravasation, growth, and finally angiogenesis in the metastatic foci. Tumor cells aggregate platelets in the bloodstream by activation of the plasmatic coagulation cascade and by direct contact formation.

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Hepcidin peptide is crucial in the regulation of systemic iron availability controlling its uptake from the diet and its release from the body storage tissues. Hepcidin dysregulation causes different human disorders ranging from iron overload (e.g.

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Due to the biological properties of heparin and low-molecular-weight heparin (LMWH), continuous advances in elucidation of their microheterogeneous structure and discovery of novel structural peculiarities are crucial. Effective strategies for monitoring manufacturing processes and assessment of more restrictive specifications, as imposed by the current regulatory agencies, need to be developed. Hereby, we apply an efficient heparanase-based strategy to assert the structure of two major isomeric octasaccharides of dalteparin and investigate the tetrasaccharides arising from antithrombin binding region (ATBR) of bovine mucosal heparin.

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Heparanase is regarded as a promising target for anticancer drugs and Ronepastat is one of the most promising heparanase inhibitors insert in clinical study for Multiple Myeloma Therapy. To improve its pharmacokinetic/pharmacodynamic profile, as well to have an antidote able to neutralize its activity in case of over dosages or intolerance, a new class of its derivatives was obtained inserting non-carbohydrate moieties of different length between the polysaccharide chain and biotin or its derivatives. In vitro these novel derivatives maintain the anti-heparanase activity without induced toxicity.

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A biological medicine (or biologicals) is a term for a medicinal compound that is derived from a living organism. By their very nature, they are complex and often heterogeneous in structure, composition and biological activity. Some of the oldest pharmaceutical products are biologicals, for example insulin and heparin.

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Heparin is a complex mixture of heterogeneous sulfated polysaccharidic chains. Its physico-chemical characterization is based on the contribution of several methods, but advantages of the use of complementary techniques have not been fully investigated yet. Strong-Anion-Exchange HPLC after enzymatic digestion and quantitative bidimensional H-C NMR (HSQC) are the most used methods for the determination of heparin structure, providing the composition of its building blocks.

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Chitin is widespread in nature and is increasingly used in synthetic process for the production of new biomaterials. Chitin degree of acetylation, crystalline structure and microfibril arrangement differentiate chemical, physical and mechanical properties. Nevertheless, no information are available on the relationship between the mechanical properties and the degree of acetylation (DA) in chitin samples in which the microfibril arrangement does not change.

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Multiple osteochondromas (MO) is a hereditary disorder associated with benign cartilaginous tumors, known to be characterized by absence or highly reduced amount of heparan sulfate (HS) in the extracellular matrix of growth plate cartilage, which alters proper signaling networks leading to improper bone growth. Although recent studies demonstrated accumulation of HS in the cytoplasm of MO chondrocytes, nothing is known on the structural alterations which prevent HS from undergoing its physiologic pathway. In this work, osteochondroma (OC), peripheral chondrosarcoma, and healthy cartilaginous human samples were processed following a procedure previously set up to structurally characterize and compare HS from pathologic and physiologic conditions, and to examine the phenotypic differences that arise in the presence of either exostosin 1 or 2 ( or ) mutations.

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Polysaccharides represent a main weight fraction of the intraskeletal organic matrix of corals, but their structure, as well as their function in the calcification process, has been poorly investigated. This communication shows by a combination of techniques (nuclear magnetic resonance, Fourier transform infrared, and monosaccharide composition) that their key component is a 1→3 β-d glucuronic acid polymer and evidences its influence in vitro in the calcification process.

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Several chronic respiratory diseases are characterized by recurrent and/or persistent infections, chronic inflammatory responses and tissue remodeling, including increased levels of glycosaminoglycans which are known structural components of the airways. Among glycosaminoglycans, heparan sulfate (HS) has been suggested to contribute to excessive inflammatory responses. Here, we aim at (i) investigating whether long-term infection by , one of the most worrisome threat in chronic respiratory diseases, may impact HS levels, and (ii) exploring HS competitors as potential anti-inflammatory drugs during pneumonia.

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Synovial sarcoma (SS) is an aggressive tumor with propensity for lung metastases which significantly impact patients' prognosis. New therapeutic approaches are needed to improve treatment outcome. Targeting the heparanase/heparan sulfate proteoglycan system by heparin derivatives which act as heparanase inhibitors/heparan sulfate mimetics is emerging as a therapeutic approach that can sensitize the tumor response to chemotherapy.

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AvidinOX, the oxidized derivative of Avidin, is a chemically modified glycoprotein, being currently under clinical investigation for targeted delivery of radioactive biotin to inoperable tumors. AvidinOX is produced by 4-hydroxyazobenzene-2-carboxylic acid (HABA)-assisted sodium periodate oxidation of Avidin. The peculiar property of the periodate-generated glycol-split carbohydrate moieties to form Schiff's bases with amino groups of the tissue proteins allows to achieve a tissue half-life of 2 weeks compared to 2 h of native Avidin.

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Danaparoid sodium salt, is the active component of ORGARAN, an anticoagulant and antithrombotic drug constituted of three glycosaminoglycans (GAGs) obtained from porcine intestinal mucosa extracts. Heparan sulfate is the major component, dermatan sulfate and chondroitin sulfate being the minor ones. Currently dermatan sulfate and chondroitin sulfate are quantified by UV detection of their unsaturated disaccharides obtained by enzymatic depolymerization.

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A number of low molecular weight heparin (LMWH) products are available for clinical use and although all share a similar mechanism of action, they are classified as distinct drugs because of the different depolymerisation processes of the native heparin resulting in substantial pharmacokinetic and pharmacodynamics differences. While enoxaparin has been extensively investigated, little information is available regarding the LMWH dalteparin. The present study is focused on the detailed structural characterization of Fragmin by LC-MS and NMR applied both to the whole drug and to its enzymatic products.

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