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1.
Int J Biol Macromol ; 163: 1649-1658, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32979436

RESUMO

The SARS-CoV-2 spike glycoproteins (SGPs) and human angiotensin converting enzyme 2 (ACE2) are the two key targets for the prevention and treatment of COVID-19. Host cell surface heparan sulfate (HS) is believed to interact with SARS-CoV-2 SGPs to facilitate host cell entry. In the current study, a series of polysaccharides from Saccharina japonica were prepared to investigate the structure-activity relationship on the binding abilities of polysaccharides (oligosaccharides) to pseudotype particles, including SARS-CoV-2 SGPs, and ACE2 using surface plasmon resonance. Sulfated galactofucan (SJ-D-S-H) and glucuronomannan (Gn) displayed strongly inhibited interaction between SARS-CoV-2 SGPs and heparin while showing negligible inhibition of the interaction between SARS-CoV-2 SGPs and ACE2. The IC50 values of SJ-D-S-H and Gn in blocking heparin SGP binding were 27 and 231 nM, respectively. NMR analysis showed that the structure of SJ-D-S-H featured with a backbone of 1, 3-linked α-L-Fucp residues sulfated at C4 and C2/C4 and 1, 3-linked α-L-Fucp residues sulfated at C4 and branched with 1, 6-linked ß-D-galacto-biose; Gn had a backbone of alternating 1, 4-linked ß-D-GlcAp residues and 1, 2-linked α-D-Manp residues. The sulfated galactofucan and glucuronomannan showed strong binding ability to SARS-CoV-2 SGPs, suggesting that these polysaccharides might be good candidates for preventing and/or treating SARS-CoV-2.


Assuntos
Infecções por Coronavirus/virologia , Glucuronatos/metabolismo , Manose/análogos & derivados , Pneumonia Viral/virologia , Polissacarídeos/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Betacoronavirus/química , Betacoronavirus/metabolismo , Sítios de Ligação , Glucuronatos/química , Heparina/química , Heparina/metabolismo , Humanos , Manose/química , Manose/metabolismo , Oligossacarídeos/química , Pandemias , Peptidil Dipeptidase A/metabolismo , Feófitas/química , Polissacarídeos/química , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/química , Relação Estrutura-Atividade
2.
Cells ; 9(9)2020 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-32899484

RESUMO

Hybrid nanoparticles from lipidic and polymeric components were assembled to serve as vehicles for the transfection of messenger RNA (mRNA) using different portions of the cationic lipid DOTAP (1,2-Dioleoyl-3-trimethylammonium-propane) and the cationic biopolymer protamine as model systems. Two different sequential assembly approaches in comparison with a direct single-step protocol were applied, and molecular organization in correlation with biological activity of the resulting nanoparticle systems was investigated. Differences in the structure of the nanoparticles were revealed by thorough physicochemical characterization including small angle neutron scattering (SANS), small angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). All hybrid systems, combining lipid and polymer, displayed significantly increased transfection in comparison to lipid/mRNA and polymer/mRNA particles alone. For the hybrid nanoparticles, characteristic differences regarding the internal organization, release characteristics, and activity were determined depending on the assembly route. The systems with the highest transfection efficacy were characterized by a heterogenous internal organization, accompanied by facilitated release. Such a system could be best obtained by the single step protocol, starting with a lipid and polymer mixture for nanoparticle formation.


Assuntos
Biopolímeros/química , Lipídeos/química , Nanopartículas/química , RNA Mensageiro/metabolismo , Transfecção/métodos , Animais , Linhagem Celular , Ácidos Graxos Monoinsaturados/química , Feminino , Heparina/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Imagem Óptica , Tamanho da Partícula , Compostos de Amônio Quaternário/química , RNA Mensageiro/química
3.
J Chromatogr A ; 1626: 461367, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797846

RESUMO

This paper analyzes the use of animal-component free chromatographic materials for the efficient purification of the human fibroblast growth factor 2 (hFGF-2). hFGF-2 is produced in Escherichia coli and purified via three different chromatography steps, which include a strong cation exchange chromatography as a capture step, followed by heparin affinity chromatography and an anion exchange chromatography as a polishing step. The affinity chromatography step is based on the animal-derived material heparin. Chemically produced ligands provide a viable alternative to animal-derived components in production processes, since they are characterized by a defined structure which leads to reproducible results and a broad range of applications. The alternative ligands can be assigned to adsorber of the mixed-mode chromatography (MMC) and pseudo-affinity chromatography. Eight different animal-component free materials used as adsorbers in MMC or pseudo-affinity chromatography were tested as a substitute for heparin. The MMCs were cation exchangers characterized with further functional residues. The ligands of the pseudo-affinity chromatography were heparin-like ligands which are based on heparin's molecular structure. The alternative methods were tested as a capture step and in combination with another chromatographic step in the purification procedure of hFGF-2. In each downstream step purity, recovery and yield were analysed and compared to the conventional downstream process. Two types of MMC - the column ForesightTM NuviaTM cPrimeTM from Bio-Rad Laboratories and the column HiTrapTM CaptoTM MMC from GE Healthcare Life Sciences - can be regarded as effective animal-component free alternatives to the heparin - based adsorber.


Assuntos
Fator 2 de Crescimento de Fibroblastos/isolamento & purificação , Adsorção , Animais , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Heparina/química , Humanos , Ligantes
4.
Chemistry ; 26(51): 11814-11818, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32515841

RESUMO

Heparin binds to and activates antithrombin (AT) through a specific pentasaccharide sequence, in which a trisaccharide subsite, containing glucuronic acid (GlcA), has been considered as the initiator in the recognition of the polysaccharide by the protein. Recently it was suggested that sulfated iduronic acid (IdoA2S) could replace this "canonical" GlcA. Indeed, a heparin octasaccharidic sequence obtained by chemoenzymatic synthesis, in which GlcA is replaced with IdoA2S, has been found to similarly bind to and activate antithrombin. By using saturation-transfer-difference (STD) NMR, NOEs, transferred NOEs (tr-NOEs) NMR and molecular dynamics, we show that, upon binding to AT, this IdoA2S unit develops comparable interactions with AT as GlcA. Interestingly, two IdoA2S units, both present in a 1 C4 -2 S0 equilibrium in the unbound saccharide, shift to full 2 S0 and full 1 C4 upon binding to antithrombin, providing the best illustration of the critical role of iduronic acid conformational flexibility in biological systems.


Assuntos
Anticoagulantes/química , Antitrombinas/química , Ácido Glucurônico/química , Heparina/química , Ácido Idurônico/química , Oligossacarídeos/química , Polissacarídeos/química , Anticoagulantes/farmacologia , Antitrombinas/metabolismo , Espectroscopia de Ressonância Magnética , Conformação Molecular , Sulfatos/química
5.
Nat Commun ; 11(1): 2694, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483155

RESUMO

Toxin complex (Tc) toxins are virulence factors of pathogenic bacteria. Tcs are composed of three subunits: TcA, TcB and TcC. TcA facilitates receptor-toxin interaction and membrane permeation, TcB and TcC form a toxin-encapsulating cocoon. While the mechanisms of holotoxin assembly and pore formation have been described, little is known about receptor binding of TcAs. Here, we identify heparins/heparan sulfates and Lewis antigens as receptors for different TcAs from insect and human pathogens. Glycan array screening reveals that all tested TcAs bind negatively charged heparins. Cryo-EM structures of Morganella morganii TcdA4 and Xenorhabdus nematophila XptA1 reveal that heparins/heparan sulfates unexpectedly bind to different regions of the shell domain, including receptor-binding domains. In addition, Photorhabdus luminescens TcdA1 binds to Lewis antigens with micromolar affinity. Here, the glycan interacts with the receptor-binding domain D of the toxin. Our results suggest a glycan dependent association mechanism of Tc toxins on the host cell surface.


Assuntos
Toxinas Bacterianas/toxicidade , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Polissacarídeos/metabolismo , Animais , Toxinas Bacterianas/química , Toxinas Bacterianas/farmacocinética , Sítios de Ligação , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células HEK293 , Heparina/química , Heparina/metabolismo , Humanos , Insetos/microbiologia , Antígenos CD15/química , Antígenos CD15/metabolismo , Modelos Moleculares , Simulação de Acoplamento Molecular , Morganella morganii/patogenicidade , Photorhabdus/patogenicidade , Polissacarídeos/química , Xenorhabdus/patogenicidade
6.
J Med Vasc ; 45(3): 147-157, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32402428

RESUMO

The recognized therapeutic effect of heparins is an anticoagulant activity (anti-Xa and anti-IIa) acting in an indirect manner (cofactor of antithrombin) but which is carried by only 20% at best of the glycan chains composing any commercial preparation of heparin, whether unfractionated or low molecular weight. However, the effects of glycan chains that participate in the therapeutic but also potentially adverse effects of heparin preparations must also be considered. These specific effects of glycans are potentially different for each commercial preparation of heparins and, in particular, low molecular weight heparins (LMWH) compared with unfractionated heparin (UFH) and LMWH between them. The glycanic nature of heparin is responsible for its very particular pharmacology: exchange with the glycocalyx of cells in particular endothelial. Exchanges which depend on the length and structure of the glycan chains therefore different between UFH and LMWH between the different heparin preparations between them but also according to the state of glycocalyx differently altered according to the underlying diseases and their degree of evolution. If the anticoagulant effects of heparins can potentially be replaced with those of new oral anticoagulants, the glycan effects of heparins cannot be replaced by synthetic non-glycan molecules. This replacement will undoubtedly limit certain risks such as heparin-induced thrombocytopenia (HIT) but other beneficial effects participating to the overall efficacy of heparin (whose relative importance remains to be ascertained), will also disappear: effects on surfaces, anti-inflammatory effects, antineoplastic and anti-metastatic effects, ancillary anticoagulant effects (not dependent on antithrombin), effect on endothelial dysfunction. This review will be focused on all of these related/pleiotropic effects of heparins that are in fact the effects of the glycan nature of heparin. Among the antithrombotic effects not dependent on antithrombin one has been more recently highlighted: the passivation/neutralization of the positively charged fibrils of Netosis, by the negatively charged glycan chains of heparin. This also has clinical implications: in the era of generics and biosimilars where biosimilar heparins begin to appear, it is important to know that accordingly to FDA and EMEA rules: their biosimilarity is judged only on the "classical" anticoagulation effect cofactor of antithrombin (anti-IIa/anti-Xa) but that all glycan effects that are potentially beneficial or potentially deleterious are not taken into consideration in their assessment.


Assuntos
Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Heparina/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Anticoagulantes/efeitos adversos , Anticoagulantes/química , Anticoagulantes/metabolismo , Antineoplásicos/uso terapêutico , Células Endoteliais/metabolismo , Glicocálix/metabolismo , Hemorragia/induzido quimicamente , Heparina/efeitos adversos , Heparina/química , Heparina/metabolismo , Humanos , Peso Molecular , Conformação Proteica , Medição de Risco , Fatores de Risco , Relação Estrutura-Atividade , Trombocitopenia/sangue , Trombocitopenia/induzido quimicamente
7.
Anesth Analg ; 130(6): 1594-1604, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32224832

RESUMO

Bleeding and coagulation management are essential aspects in the management of neonates and children undergoing cardiac surgery. The use of point-of-care tests (POCTs) in a pediatric setting is not as widely used as in the adult setting. This systematic review aims to summarize the evidence showed by the literature regarding the use of POCTs in children undergoing cardiac surgery. We included all studies examining the pediatric population (<18 years old) undergoing cardiac surgery in which the coagulation profile was assessed with POCTs. Three electronic databases (PubMed, Embase, and the Cochrane Controlled Clinical Trials register) were searched. Tests involved were heparin effect tests, viscoelastic tests, and platelet function tests. Due to the wide heterogeneity of the patients and tests studied, a formal meta-analysis was impossible, and the results are therefore presented through a systematic review. Eighty articles were found, of which 47 are presented in this review. At present, literature data are too weak to define POCTs as a "gold standard" for the treatment of perioperative bleeding in pediatric cardiac surgery. Nevertheless, introduction of POCTs into postoperative algorithms has shown to improve bleeding management, patient outcome, and cost efficiency.


Assuntos
Anticoagulantes/uso terapêutico , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Testes Imediatos , Hemorragia Pós-Operatória/prevenção & controle , Adolescente , Algoritmos , Coagulação Sanguínea/efeitos dos fármacos , Testes de Coagulação Sanguínea , Perda Sanguínea Cirúrgica , Criança , Pré-Escolar , Cianose/complicações , Elasticidade , Fibrinólise , Heparina/química , Heparina/uso terapêutico , Humanos , Lactente , Recém-Nascido , Testes de Função Plaquetária , Hemorragia Pós-Operatória/sangue , Tromboelastografia , Viscosidade
8.
Adv Exp Med Biol ; 1221: 169-188, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32274710

RESUMO

Heparanase is the principal enzyme that degrades heparan sulfate (HS) in both physiological (HS turnover) and pathological (tumor metastasis, inflammation) cell conditions, catalysing the hydrolysis of the ß-1-4 glycosidic bond in -GlcUA-ß(1-4)-GlcNX-. Despite efforts to define the minimum trisaccharide sequence that allows glycans to be recognized by heparanase, a rigorous "molecular code" by which the enzyme reads and degrades HS chains has not been identified. The X-ray diffraction model of heparanase, resolved by Wu et al (2015), revealed a complex between the trisaccharide GlcNS6S-GlcUA-GlcNS6S and heparanase. Efforts are ongoing to better understand how HS mimetics longer than three residues are recognized by heparanase before being hydrolyzed or inhibit the enzyme. It is also important to consider the flexibility of the enzyme active site, a feature that opens up the development of heparanase inhibitors with structures significantly different from HS or heparin. This chapter reviews the state-of-the-art knowledge about structural aspects of heparanase activities in terms of substrate recognition, mechanism of hydrolysis, and inhibition.


Assuntos
Glucuronidase , Glicóis , Heparina , Heparitina Sulfato , Glucuronidase/antagonistas & inibidores , Glucuronidase/química , Glucuronidase/metabolismo , Glicóis/química , Glicóis/metabolismo , Heparina/química , Heparina/metabolismo , Heparitina Sulfato/química , Heparitina Sulfato/metabolismo , Humanos , Hidrólise , Especificidade por Substrato
9.
Adv Exp Med Biol ; 1221: 493-522, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32274724

RESUMO

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-ß-D-glucuronidase is overexpressed in cancer, inflammation, diabetes, atherosclerosis, nephropathies and other pathologies. Starting from known low- or non-anticoagulant heparins, the search for heparanase inhibitors evolved focusing on structure-activity relationship studies and taking advantage of new chemical-physical analytical methods which have allowed characterization and sequencing of polysaccharide chains. New methods to screen heparanase inhibitors and to evaluate their mechanism of action and in vivo activity in experimental models prompted their development. New non-anticoagulant heparin derivatives endowed with anti-heparanase activity are reported. Some leads are under clinical evaluation in the oncology field (e.g., acute myeloid leukemia, multiple myeloma, pancreatic carcinoma) and in other pathological conditions (e.g., sickle cell disease, malaria, labor arrest).


Assuntos
Glucuronidase/antagonistas & inibidores , Heparina/análogos & derivados , Heparina/farmacologia , Animais , Glucuronidase/metabolismo , Heparina/química , Heparitina Sulfato/metabolismo , Humanos , Neoplasias/tratamento farmacológico
10.
Adv Exp Med Biol ; 1221: 567-603, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32274727

RESUMO

Despite the enormous progress made in recent years with antibodies, vaccines, antisense oligonucleotides, etc., the so-called "biological" approaches for tackling the control of various diseases, medicinal chemistry remains a bulwark to refer to for the development of new drugs. Also in the case of heparanase, medicinal chemistry has always been in the forefront to identify new inhibitors, through modification of natural macromolecules, e.g., sulfated polysaccharides like heparin, or of natural compounds isolated from bacteria or plants, or through rational design. In this chapter, the reader will find a detailed description of the most relevant small-molecule heparanase inhibitors reported so far in the scientific literature and in patent applications, with mention to the design strategy and to structure-activity relationships. Starting from heparanase inhibitors of natural origin and the attempts to improve their potency and selectivity, the reader will be guided through the major chemical classes of synthetic inhibitors, with representation of the structure of the most relevant compounds. The last paragraph is dedicated to a brief description of inhibitors that have reached clinical trials, highlighting their structure, mechanism, and improved derivatives.


Assuntos
Glucuronidase/antagonistas & inibidores , Heparina/análogos & derivados , Heparina/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Heparina/farmacologia , Humanos , Relação Estrutura-Atividade
11.
Adv Exp Med Biol ; 1221: 523-538, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32274725

RESUMO

A growing interest around heparanase and its role in cancer, inflammation and other diseases prompted the identification of specific inhibitors of this enzyme and the exploration of their potential therapeutic role. Roneparstat, a 15-25 kDa N-acetylated and glycol split heparin, is one of the most potent and widely studied heparanase inhibitors. These studies generated a large body of data, which allowed to characterize Roneparstat properties and to endorse its potential therapeutic role. Multiple Myeloma represents the indication that most of the studies, including the phase I clinical trial, addressed. However, Roneparstat antitumor activity activity has been documented in other cancers, and in non-oncological conditions.In addition, assessing Roneparstat activity in different experimental models contributed to understanding heparanase role and the biological factors that may be affected by heparanase inhibition in more detail. Finally, some studies elucidated the molecular mechanisms regulating the enzyme-inhibitor kinetics, thus providing important data for the identification and design of new inhibitors.The objective of this chapter is to provide a comprehensive overview of the most significant studies involving Roneparstat and discuss its potential role in therapy.


Assuntos
Heparina/análogos & derivados , Mieloma Múltiplo/tratamento farmacológico , Animais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Glucuronidase/antagonistas & inibidores , Glucuronidase/metabolismo , Heparina/química , Heparina/farmacologia , Heparina/uso terapêutico , Humanos
12.
J Dairy Sci ; 103(6): 5509-5513, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32307153

RESUMO

The objectives of this study were to describe the stability of bovine whole-blood electrolytes, glucose, and lactate in samples collected in lithium heparin tubes and stored in thermoconductive modules immersed in ice water. A total of 99 Jersey cows (40 first-parity, 18 second-parity, and 41 third-parity or greater cows) from a commercial dairy farm in West Texas were enrolled between June and July 2018. Blood was collected from the jugular vein using a 60-mL polypropylene syringe and equally distributed into 5 spray-dried evacuated lithium heparin tubes. Baseline samples were analyzed within 90 s of collection using a benchtop blood gas analyzer. The remaining 4 tubes were stored in a thermoconductive, passive-temperature-regulating module inside a cooler with ice water. At 30 min and 2, 4, and 8 h post-collection, samples were removed from the temperature-regulating module, gently inverted for 10 s, and analyzed. Repeated-measures models were built to evaluate the effect of time on the stability of ionized Ca (iCa), ionized Mg (iMg), Na, K, Cl, glucose, and lactate. Most of the analytes investigated remained stable up to 8 h under ice water storage conditions before analysis, including iCa, iMg, Cl, glucose, and lactate. However, Na and K were significantly affected by delayed analysis: Na remained stable up to 4 h post-collection, but K was not stable starting at 2 h post-collection. The results of this study are useful in helping future researchers and consultants to recognize acceptable time delays between whole blood collection and processing or analysis for electrolytes, glucose, and lactate.


Assuntos
Coleta de Amostras Sanguíneas/veterinária , Bovinos/sangue , Eletrólitos/sangue , Heparina/química , Animais , Gasometria/veterinária , Glicemia/análise , Cálcio/sangue , Cloretos/sangue , Feminino , Ácido Láctico/sangue , Lítio/química , Magnésio/sangue , Potássio/sangue , Refrigeração/veterinária , Sódio/sangue , Texas , Fatores de Tempo
13.
Mikrochim Acta ; 187(4): 226, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170394

RESUMO

Heparin was employed as the stabilizing agent in the synthesis of peroxidase-mimicking Pd nanoparticles. The heparin-capped Pd nanozyme can act as both the signal amplifier and the selective binder of protamine. The most efficient nanozyme with the mean size of 3.5 nm consists of 70.8% metallic Pd0 and 29.2% Pd2+ species. Enzyme kinetic studies show that the Km values are 0.036 mM for 3,3',5,5'-tetramethylbenzidine and 78 mM for H2O2. Protamine shows strong affinity to the heparin-capped Pd nanozyme, and induces an apparent aggregation of the nanoparticles. This results in a significant inhibition of the peroxidase-mimicking activities. Hence, the oxidation of TMB by H2O2 to a blue product with a maximum absorption at 652 nm is suppressed. Based on this finding, a photometric assay is developed for the determination of protamine. The linear response is in the concentration range 0.02 ~ 0.8 µg mL-1, and the limit of detection is 0.014 µg mL-1. This assay presents high selectivity toward other biological substances. Graphical abstract Highly active and selective Pd nanozyme was synthesized through adopting heparin as the capping agent for quantitative determination of protamine.


Assuntos
Heparina/química , Nanopartículas/química , Paládio/química , Peroxidase/química , Fotometria , Protaminas/análise , Heparina/metabolismo , Nanopartículas/metabolismo , Paládio/metabolismo , Peroxidase/metabolismo , Protaminas/metabolismo
14.
Talanta ; 211: 120707, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32070586

RESUMO

In this study, a colorimetric sensing assay of isoniazid based on excellent oxidase-like activity of heparin sodium stabilized platinum nanoparticles (HS-PtNPs) has been demonstrated. The newly prepared HS-PtNPs exhibit a great dispersion with an average size distribution of 4.8 ± 0.6 nm, and maintain more than 90% catalytic activity under strong acid and alkali or long-term storage conditions, indicating a robust nanomaterial with attractive potential. The HS-PtNPs show distinct oxidase-like activity with an ultrahigh affinity (Km = 0.01012 mM) for 3, 3', 5, 5'-tetramethylbenzidine (TMB). More significantly, we found that the pyridine ring of isoniazid has a strong reductive hydrazyl substitution, which can compete with TMB for the catalytic site of HS-PtNPs resulting in a colorless solution. Accordingly, a colorimetric sensing of isoniazid was fabricated. A linear relationship for isoniazid was achieved in 2.5 × 10-6 to 2.5 × 10-4 M (R2 = 0.998) with a low limit of detection 1.7 × 10-6 M (S/N = 3). Recovery experiments in drug tablets show that the standard recovery rates were 95%-103%. The quantitative detection data for isoniazid in drug tablets calculated respectively from the standard method and this method exhibited a high correlation coefficient (a slope of 0.9995), suggesting that high accuracy in isoniazid detection.


Assuntos
Antituberculosos/análise , Heparina/química , Isoniazida/análise , Nanopartículas Metálicas/química , Platina/química , Antituberculosos/química , Benzidinas/química , Colorimetria , Isoniazida/química , Oxirredutases/química , Comprimidos
15.
Carbohydr Polym ; 231: 115695, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888803

RESUMO

Building blocks characterization is a significant approach for understanding the molecular structure of heparin and its derivatives. Nitrous acid (HONO) depolymerization of heparin generates oligosaccharides that maintain the epimerization conformation on C5 of the uronic acids, reflecting the authentic structure of the parental chain. HONO treatment at pH 1.5 selectively cleaves the bond between N-sulfated glucosamine and hexuronic acid, resulting mainly disaccharides, as well as tetra-, tri-, and mono-saccharides. The tetrasaccharides are derived from the structure of N-acetylated domains while tri-, and mono-saccharides are derived from the reducing or the non-reducing end of the heparin chain. The resulted oligosaccharides were separated and analyzed using a UHPLC-HILIC/WAX-MS method. We succeeded in the identification of 19 tetrasaccharides, 19 trisaccharides and 4 monosaccharides species, majority of which is structurally characterized. By comparing the theoretical possibilities and actual occurrence of the well-characterized tetrasaccharides, we demonstrated that the biosynthesis of heparin is a systematic process.


Assuntos
Heparina/química , Estrutura Molecular , Ácido Nitroso/química , Oligossacarídeos/química , Sequência de Carboidratos/genética , Cromatografia Líquida de Alta Pressão , Dissacarídeos/química , Glucosamina/química , Heparina Liase/química , Espectroscopia de Ressonância Magnética , Oligossacarídeos/genética , Polissacarídeo-Liase/química , Trissacarídeos/química
16.
Carbohydr Polym ; 230: 115654, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887958

RESUMO

A novel fluorescent heparanase assay based on hybrid nano-assembly of gold nanocluster and glycosaminoglycan is developed. The nanoparticle probes are fabricated through the co-assembly of positively charged gold nanoclusters with negatively charged heparin molecules, which is accompanied by a dramatic size change and a 2.5-fold fluorescence enhancement. It is demonstrated that the fluorescence enhancement is due to denser aggregation of Au-thiolate complexes in the hybrid nanoparticle and the fluctuation of the fluorescence intensity is an indicator of the variation in assembly efficiency. Experiments in solution and in cell lysis media showed that the heparanase could turn-off the fluorescence with a high selectivity, which could be utilized for the assessment of heparanase activity and the metastatic potentials of different tumour cells. This assay technique is low cost, easy to prepare, and showing good performance. The co-assembly strategy has potential to be transferable to construct other functional nanomaterial.


Assuntos
Técnicas Biossensoriais/métodos , Fluorescência , Ouro , Heparina , Nanopartículas Metálicas/química , Neoplasias/diagnóstico por imagem , Animais , Ouro/química , Ouro/farmacologia , Células HeLa , Heparina/química , Heparina/farmacologia , Humanos , Células MCF-7 , Camundongos , Células NIH 3T3
17.
FASEB J ; 34(1): 446-457, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914682

RESUMO

Mechanical damage or infection to the endometrium can lead to the formation of adhesions in the uterine cavity, which may result in reduced reproductive outcome and/or pregnancy complications. The prognosis of this disease is poor due to few effective treatments and the complex environment of endometrium. Heparin-Poloxamer Hydrogel (HP hydrogel) is a nontoxic and biodegradable biomaterial, which has been commonly used as a sustained-release delivery system. In this study, we applied a mini-endometrial curette to scrape the endometrium of rats to mimic the process of curettage in patients. After the establishment of IUA model in rats, we injected the thermo-sensitive hydrogel(E2-HP hydrogel) into the injured uterine cavity and evaluated the therapeutic effect of E2-HP hydrogel on the recovery of IUA. Our results showed that E2-HP hydrogel can significantly facilitate the regeneration of injured endometrium along with inhibiting the cell apoptosis in IUA model. Furthermore, we revealed that E2-HP hydrogel on the recovery of IUA was closely associated with the upregulation of kisspeptin through activating the ERK1/2 and MAPKs p38 pathways. In conclusion, E2-HP hydrogel can effectively transfer E2 into the injured endometrium and it can be considered as a promising therapeutic method for the women with intrauterine adhesions.


Assuntos
Endométrio/citologia , Estradiol/farmacologia , Heparina/química , Hidrogéis/farmacologia , Poloxâmero/química , Regeneração , Aderências Teciduais/tratamento farmacológico , Útero/citologia , Animais , Endométrio/efeitos dos fármacos , Endométrio/lesões , Estradiol/química , Feminino , Hidrogéis/química , Gravidez , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Útero/efeitos dos fármacos , Útero/lesões
18.
Carbohydr Polym ; 230: 115592, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887923

RESUMO

The complicated preparation procedure and carrier's suspicious biocompatibility are two major limitations for traditional drug carrier. In this manuscript, a novel polyion complex (PIC) was prepared by simply mixing two biocompatible components, thiolated heparin and doxorubicin (DOX), and subsequently crosslinking under atmosphere, so that it can overcome the above limitations. The PIC's particle size kept stable for one week storage in PBS, and the particles wouldn't decomposed by the dilution, indicating excellent storage and anti-dilution stability resulting from the crosslinking. The PIC can release the larger amount of DOX in acidic environment than psychological environment, and largest amount in acidic and glutathione (GSH) environment, showing the pH and GSH dual sensitive drug release behavior. Furthermore, the PIC exhibited obvious tumor inhibition effect in vivo as well as long circulation ability and low heart toxicity by anti-tumor tests on tumor-bearing mice. Consequently, as-prepared PIC shows promising potential in drug carrier application.


Assuntos
Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Glutationa/química , Heparina/farmacologia , Neoplasias/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Glutationa/genética , Heparina/química , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Micelas , Neoplasias/genética , Compostos de Sulfidrila/química
19.
Sci Adv ; 6(1): eaay1240, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31922007

RESUMO

Supraphysiologic doses of bone morphogenetic protein-2 (BMP-2) are used clinically to promote bone formation in fracture nonunions, large bone defects, and spinal fusion. However, abnormal bone formation (i.e., heterotopic ossification) caused by rapid BMP-2 release from conventional collagen sponge scaffolds is a serious complication. We leveraged the strong affinity interactions between heparin microparticles (HMPs) and BMP-2 to improve protein delivery to bone defects. We first developed a computational model to investigate BMP-2-HMP interactions and demonstrated improved in vivo BMP-2 retention using HMPs. We then evaluated BMP-2-loaded HMPs as a treatment strategy for healing critically sized femoral defects in a rat model that displays heterotopic ossification with clinical BMP-2 doses (0.12 mg/kg body weight). HMPs increased BMP-2 retention in vivo, improving spatial localization of bone formation in large bone defects and reducing heterotopic ossification. Thus, HMPs provide a promising opportunity to improve the safety profile of scaffold-based BMP-2 delivery.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Regeneração Óssea/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Osteogênese/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Animais , Proteína Morfogenética Óssea 2/química , Regeneração Óssea/genética , Colágeno/química , Fêmur/crescimento & desenvolvimento , Fêmur/patologia , Heparina/química , Heparina/farmacologia , Humanos , Ossificação Heterotópica/tratamento farmacológico , Ossificação Heterotópica/genética , Ossificação Heterotópica/patologia , Ratos , Proteínas Recombinantes/química , Fator de Crescimento Transformador beta/genética , Microtomografia por Raio-X
20.
Colloids Surf B Biointerfaces ; 188: 110768, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31945629

RESUMO

Thrombosis is a main complication of cancer. It can increase the mortality of cancer patients. Therefore, the anticoagulant heparin (Hep) as an adjuvant therapy was introduced to the drug delivery system based on doxorubicin hydrochloride (DOX)-carbon dots (CDs)-Hyaluronic acid (HA), which obviously enhanced the blood compatibility of the system. Drug release process of the CDs-HA-Hep/DOX system was dual-responsive by HA and pH value. Results of in vitro MTT and scratch tests demonstrated that the drug delivery system could targetedly inhibit growth and migration of cancerous cells. In addition, the system allows visual tracking of the drug based on fluorescence of CDs.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Carbono/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Heparina/química , Ácido Hialurônico/química , Pontos Quânticos/química , Antibióticos Antineoplásicos/química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
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