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1.
J Virol ; 95(4)2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33219167

RESUMO

Among seven coronaviruses that infect humans, three (severe acute respiratory syndrome coronavirus [SARS-CoV], Middle East respiratory syndrome coronavirus [MERS-CoV], and the newly identified severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) are associated with a severe, life-threatening respiratory infection and multiorgan failure. We previously proposed that the cationically modified chitosan N-(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (HTCC) is a potent inhibitor of human coronavirus NL63 (HCoV-NL63). Next, we demonstrated the broad-spectrum antiviral activity of the compound, as it inhibited all low-pathogenicity human coronaviruses (HCoV-NL63, HCoV-229E, HCoV-OC43, and HCoV-HKU1). Here, using in vitro and ex vivo models of human airway epithelia, we show that HTCC effectively blocks MERS-CoV and SARS-CoV-2 infection. We also confirmed the mechanism of action for these two viruses, showing that the polymer blocks the virus entry into the host cell by interaction with the S protein.IMPORTANCE The beginning of 2020 brought us information about the novel coronavirus emerging in China. Rapid research resulted in the characterization of the pathogen, which appeared to be a member of the SARS-like cluster, commonly seen in bats. Despite the global and local efforts, the virus escaped the health care measures and rapidly spread in China and later globally, officially causing a pandemic and global crisis in March 2020. At present, different scenarios are being written to contain the virus, but the development of novel anticoronavirals for all highly pathogenic coronaviruses remains the major challenge. Here, we describe the antiviral activity of an HTCC compound, previously developed by us, which may be used as a potential inhibitor of currently circulating highly pathogenic coronaviruses-SARS-CoV-2 and MERS-CoV.


Assuntos
Tratamento Farmacológico da COVID-19 , Quitosana/análogos & derivados , Infecções por Coronavirus/tratamento farmacológico , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , COVID-19/epidemiologia , COVID-19/virologia , Quitosana/farmacologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Pandemias , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/virologia , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos
2.
Int J Mol Sci ; 23(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36012551

RESUMO

Recombinant human bone morphogenetic protein-2 (rhBMP-2) plays a key role in the stem cell response, not only via its influence on osteogenesis, but also on cellular adhesion, migration, and proliferation. However, when applied clinically, its supra-physiological levels cause many adverse effects. Therefore, there is a need to concomitantly retain the biological activity of BMP-2 and reduce its doses. Currently, the most promising strategies involve site-specific and site-directed immobilization of rhBMP-2. This work investigated the covalent and electrostatic binding of rhBMP-2 to ultrathin-multilayers with chondroitin sulfate (CS) or diazoresin (DR) as the topmost layer. Angle-resolved X-ray photoelectron spectroscopy was used to study the exposed chemical groups. The rhBMP-2 binding efficiency and protein state were studied with time-of-flight secondary ion mass spectrometry. Quartz crystal microbalance, atomic force microscopy, and enzyme-linked immunosorbent assay were used to analyze protein-substrate interactions. The effect of the topmost layer was tested on initial cell adhesion and short-term osteogenesis marker expression. The results show the highest expression of selected osteomarkers in cells cultured on the DR-ended layer, while the cellular flattening was rather poor compared to the CS-ended system. rhBMP-2 adhesion was observed only on negatively charged layers. Cell flattening became more prominent in the presence of the protein, even though the osteogenic gene expression decreased.


Assuntos
Proteína Morfogenética Óssea 2 , Células-Tronco Mesenquimais , Proteína Morfogenética Óssea 2/metabolismo , Adesão Celular , Diferenciação Celular , Células Cultivadas , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Células-Tronco/metabolismo , Fator de Crescimento Transformador beta/farmacologia
3.
Int J Mol Sci ; 22(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34681808

RESUMO

Uncontrolled bleeding after enoxaparin (ENX) is rare but may be life-threatening. The only registered antidote for ENX, protamine sulfate (PS), has 60% efficacy and can cause severe adverse side effects. We developed a diblock copolymer, heparin-binding copolymer (HBC), that reverses intravenously administered heparins. Here, we focused on the HBC inhibitory activity against subcutaneously administered ENX in healthy mice. BALB/c mice were subcutaneously injected with ENX at the dose of 5 mg/kg. After 110 min, vehicle, HBC (6.25 and 12.5 mg/kg), or PS (5 and 10 mg/kg) were administered into the tail vein. The blood was collected after 3, 10, 60, 120, 360, and 600 min after vehicle, HBC, or PS administration. The activities of antifactors Xa and IIa and biochemical parameters were measured. The main organs were collected for histological analysis. HBC at the lower dose reversed the effect of ENX on antifactor Xa activity for 10 min after antidote administration, whereas at the higher dose, HBC reversed the effect on antifactor Xa activity throughout the course of the experiment. Both doses of HBC completely reversed the effect of ENX on antifactor IIa activity. PS did not reverse antifactor Xa activity and partially reversed antifactor IIa activity. HBC modulated biochemical parameters. Histopathological analysis showed changes in the liver, lungs, and spleen of mice treated with HBC and in the lungs and heart of mice treated with PS. HBC administered in an appropriate dose might be an efficient substitute for PS to reverse significantly increased anticoagulant activity that may be connected with major bleeding in patients receiving ENX subcutaneously.


Assuntos
Enoxaparina/efeitos adversos , Hemorragia/tratamento farmacológico , Protaminas/uso terapêutico , Animais , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Testes de Coagulação Sanguínea , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Enoxaparina/administração & dosagem , Feminino , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Heparina/metabolismo , Antagonistas de Heparina/metabolismo , Antagonistas de Heparina/farmacologia , Antagonistas de Heparina/uso terapêutico , Infusões Subcutâneas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Polímeros/química , Polímeros/metabolismo , Polímeros/farmacologia , Polímeros/uso terapêutico , Protaminas/metabolismo , Protaminas/farmacologia , Ligação Proteica
4.
J Pharmacol Exp Ther ; 373(1): 51-61, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31937564

RESUMO

Bleeding resulting from the application of low-molecular-weight heparins (LMWHs) may be treated with protamine sulfate, but this treatment lacks efficiency; its action against antifactor Xa activity is limited to ∼60%. Moreover, protamine sulfate can cause life-threatening hypersensitivity reactions. We developed diblock heparin-binding copolymer (HBC), which can neutralize the anticoagulant activity of parenteral anticoagulants. In the present study, we explored the safety profile of HBC and its potential to reverse enoxaparin, nadroparin, dalteparin, and tinzaparin in human plasma and at in vivo conditions. HBC-LMWH complexes were characterized using zeta potential, isothermal titration calorimetry, and dynamic light scattering. The rat cardiomyocytes and human endothelial cells were used for the assessment of in vitro toxicity. Male Wistar rats were observed for up to 4 days after HBC administration for clinical evaluation, gross necropsy, and biochemistry and histopathological analysis. Rats were treated with LMWHs alone or followed by short-time intravenous infusion of HBC, and bleeding time and antifactor Xa activity were measured. HBC completely reversed antifactor Xa activity prolonged in vitro by all LMWHs with an optimal weight ratio of 2.5:1. The complexes of HBC-LMWHs were below 5 µm. We observed no effects on the viability of cardiovascular cells treated with HBC at concentrations up to 0.05 mg/ml. Single doses up to 20 mg/kg of HBC were well tolerated by rats. HBC completely reversed the effects of LMWHs on bleeding time and antifactor Xa activity in vivo after 20 minutes and retained ∼80% and ∼60% of reversal activity after 1 and 2 hours, respectively. Well-documented efficacy and safety of HBC both in vitro and in vivo make this polymer a promising candidate for LMWHs reversal. SIGNIFICANCE STATEMENT: Over the last decade, there has been significant progress in developing antidotes for the reversal of anticoagulants. Until now, there has been no effective and safe treatment for patients with severe bleeding under low-molecular-weight heparin therapy. Based on our in vitro and in vivo studies, heparin-binding copolymer seems to be a promising candidate for neutralizing all clinically relevant low-molecular-weight heparins.


Assuntos
Anticoagulantes/metabolismo , Antídotos/metabolismo , Hemorragia/metabolismo , Heparina de Baixo Peso Molecular/metabolismo , Animais , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Antídotos/farmacologia , Antídotos/uso terapêutico , Relação Dose-Resposta a Droga , Fator Xa/metabolismo , Hemorragia/prevenção & controle , Heparina/efeitos adversos , Heparina/metabolismo , Heparina de Baixo Peso Molecular/efeitos adversos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Distribuição Aleatória , Ratos , Ratos Wistar
5.
Bioorg Med Chem ; 27(7): 1414-1420, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30808605

RESUMO

A cationic derivative of γ-cyclodextrin (GCD) modified with propylenediamine (PDA) was synthesized. It was shown that the derivative (GCD-PDA) is mucoadhesive and resistant to the digestion with ∝-amylase indicating that it may constitute an efficient oral delivery vehicle. GCD-PDA formed an inclusion complex with berberine (BBR), an alkaloid displaying a multitude of beneficial physiological effects. The complexed BBR penetrates a lipid membrane easier than the free one. Both uncomplexed BBR and that complexed with GCD-PDA was delivered to normal (NMuMG) and cancerous (4T1) murine mammary gland cells. In the normal cells both free and complexed BBR was homogeneously dispersed in the cytoplasm and was nontoxic up to 131 µM. In the cancerous cells uncomplexed BBR was also homogeneously dispersed but it was toxic to about 25% of cells at 131 µM, while the GCD-PDA/BBR complex was preferably localized in lysosomes and its toxicity doubled at this concentration compared to that of free BBR. Moreover, free BBR and GCD-PDA/BBR showed even more efficient inhibitory effect against murine melanoma (B16-F10) cells than against 4T1 cells.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , gama-Ciclodextrinas/química , gama-Ciclodextrinas/farmacologia , Animais , Antineoplásicos/síntese química , Cátions/síntese química , Cátions/química , Cátions/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , gama-Ciclodextrinas/síntese química
6.
Mar Drugs ; 17(9)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533230

RESUMO

Protamine sulfate (PS) is a polycationic protein drug obtained from the sperm of fish, and is used to reverse the anticoagulant effect of unfractionated heparin (UFH). However, the interactions between PS, UFH, and platelets are still not clear. We measured the platelet numbers and collagen-induced aggregation, P-selectin, platelet factor 4, ß-thromboglobulin, prostacyclin metabolite, D-dimers, activated partial thromboplastin time, prothrombin time, anti-factor Xa, fibrinogen, thrombus weight and megakaryocytopoiesis in blood collected from mice and rats in different time points.. All of the groups were treated intravenously with vehicle, UFH, PS, or UFH with PS. We found a short-term antiplatelet activity of PS in mice and rats, and long-term platelet-independent antithrombotic activity in rats with electrically-induced thrombosis. The antiplatelet and antithrombotic potential of PS may contribute to bleeding risk in PS-overdosed patients. The inhibitory effect of PS on the platelets was attenuated by UFH without inducing thrombocytopenia. Treatment with UFH and PS did not affect the formation, number, or activation of platelets, or the thrombosis development in rodents.


Assuntos
Anticoagulantes/efeitos adversos , Antagonistas de Heparina/efeitos adversos , Heparina/efeitos adversos , Protaminas/efeitos adversos , Trombocitopenia/diagnóstico , Animais , Anticoagulantes/administração & dosagem , Plaquetas/efeitos dos fármacos , Modelos Animais de Doenças , Hemorragia/sangue , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Heparina/administração & dosagem , Antagonistas de Heparina/administração & dosagem , Humanos , Masculino , Camundongos , Tempo de Tromboplastina Parcial , Agregação Plaquetária/efeitos dos fármacos , Protaminas/administração & dosagem , Ratos , Trombocitopenia/sangue , Trombocitopenia/induzido quimicamente , Fatores de Tempo
7.
Biomacromolecules ; 19(7): 3104-3118, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29733637

RESUMO

Di- and triblock copolymers with low dispersity of molecular weight were synthesized using radical addition-fragmentation chain transfer polymerization. The copolymers contained anionic poly(sodium 2-acrylamido-2-methylpropanesulfonate) (PAMPS) block as an anticoagulant component. The block added to lower the toxicity was either poly(ethylene glycol) (PEG) or poly(2-(methacryloyloxy)ethyl phosphorylcholine) (PMPC). The polymers prolonged clotting times both in vitro and in vivo. The influence of the polymer architecture and composition on the efficacy of anticoagulation and safety parameters was evaluated. The polymer with the optimal safety/efficacy profile was PEG47- b-PAMPS108, i.e., a block copolymer with the degrees of polymerization of PEG and PAMPS blocks equal to 47 and 108, respectively. The anticoagulant action of copolymers is probably mediated by antithrombin, but it differs from that of unfractionated heparin. PEG47- b-PAMPS108 also inhibited platelet aggregation in vitro and increased the prostacyclin production but had no antiplatelet properties in vivo. PEG47- b-PAMPS108 anticoagulant activity can be efficiently reversed with a copolymer of PEG and poly((3-(methacryloylamino)propyl)trimethylammonium chloride) (PMAPTAC) (PEG41- b-PMAPTAC53, HBC), which may be attributed to the formation of polyelectrolyte complexes with PEG shells without anticoagulant properties.


Assuntos
Anticoagulantes/síntese química , Polímeros/química , Ácidos Sulfônicos/química , Animais , Anticoagulantes/farmacologia , Masculino , Metacrilatos/química , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Agregação Plaquetária/efeitos dos fármacos , Polietilenoglicóis/química , Polímeros/farmacologia , Ratos , Ratos Wistar , Ácidos Sulfônicos/farmacologia
8.
Nanotechnology ; 28(4): 045701, 2017 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-27977416

RESUMO

Novel, highly fluorescent cadmium telluride quantum dots conjugated with thymine and stabilized with thioglycolic acid were obtained and characterized. Successful formation of the conjugate was confirmed by elemental analysis, and UV-vis, fluorescence and Fourier transform infrared spectroscopies. Crystal structure and composition of the conjugates were characterized with xray diffraction and x-ray photoelectron spectroscopy. The size of the conjugates was 4-6 nm as demonstrated using atomic force microscopy and high resolution transmission electron microscopy imaging. The plasmon resonance fluorescence band at 540 nm on excitation at 351 nm was observed for these nanoparticles. The intensity of this band increased with the increase in the amount of conjugated thymine with no shift in its position. Based on the fluorescence measurements it was found that the CdTe-thymine conjugate interacted efficiently and selectively not only with adenine, a nucleobase complementary to thymine, but also with adenine-containing modified nucleosides, i.e., 5'-deoxy-5'-(methylthio)adenosine and 2'-O-methyladenosine, the urinary tumor markers which allow monitoring of the disease progression. To the best of our knowledge, as yet, there have been no studies presented in literature on that type of the interaction with CdTe-thymine conjugates. Therefore, the system presented can be considered as a working component of a selective adenine/adenosine biosensor with potential application in cancer diagnosis.

9.
Antimicrob Agents Chemother ; 60(4): 1955-66, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26729490

RESUMO

Novel sulfonated derivatives of poly(allylamine hydrochloride) (NSPAHs) and N-sulfonated chitosan (NSCH) have been synthesized, and their activity against influenza A and B viruses has been studied and compared with that of a series of carrageenans, marine polysaccharides of well-documented anti-influenza activity. NSPAHs were found to be nontoxic and very soluble in water, in contrast to gel-forming and thus generally poorly soluble carrageenans.In vitroandex vivostudies using susceptible cells (Madin-Darby canine kidney epithelial cells and fully differentiated human airway epithelial cultures) demonstrated the antiviral effectiveness of NSPAHs. The activity of NSPAHs was proportional to the molecular mass of the chain and the degree of substitution of amino groups with sulfonate groups. Mechanistic studies showed that the NSPAHs and carrageenans inhibit influenza A and B virus assembly in the cell.


Assuntos
Antivirais/farmacologia , Quitosana/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza B/efeitos dos fármacos , Poliaminas/farmacologia , Polímeros/farmacologia , Ésteres do Ácido Sulfúrico/farmacologia , Animais , Antivirais/síntese química , Quitosana/síntese química , Cães , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/crescimento & desenvolvimento , Vírus da Influenza B/genética , Vírus da Influenza B/crescimento & desenvolvimento , Concentração Inibidora 50 , Células Madin Darby de Rim Canino , Poliaminas/síntese química , Polieletrólitos , Polímeros/síntese química , RNA Viral/antagonistas & inibidores , RNA Viral/biossíntese , Relação Estrutura-Atividade , Ésteres do Ácido Sulfúrico/síntese química , Montagem de Vírus/efeitos dos fármacos , Ligação Viral/efeitos dos fármacos , Inativação de Vírus/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
10.
J Sep Sci ; 39(15): 3072-80, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27296785

RESUMO

Modified adenosine nucleosides have been proposed to be potential DNA-based biomarkers for early diagnosis of tumor and a promising tool for the development of noninvasive prediction systems. However, the low concentration of modified adenosine nucleosides in physiological fluids makes them challenging for both quantitative and qualitative determination. Therefore, materials, which are potentially useful for selective adsorption of nucleobase-containing compounds, were obtained. To obtain the adsorbents, the silica gel particles were coated layer-by-layer with films of the polymers with different combinations of polymers containing thymine groups. Next, the microspheres were irradiated with UV light in the presence of 2'-deoxyadenosine or 5'-deoxy-5'-(methylthio)adenosine, as template molecules, which resulted in the photodimerization of thymine moieties and molecular imprinting of adsorbed modified adenosine compounds. The selectivity of the adsorption was significantly enhanced by the photoimprinting process. Eventually, the imprinted particles have shown an improved ability to recognize mainly 2'-deoxyadenosine and 5'-deoxy-5'-(methylthio)adenosine molecules. The best performing adsorbent was obtained using modified natural polysaccharides. The studied materials could serve as promising adsorbents of biomarkers for tumor diagnostics.


Assuntos
Adenosina/isolamento & purificação , Biomarcadores Tumorais/isolamento & purificação , Impressão Molecular , Adenosina/química , Adsorção , Biomarcadores Tumorais/química , Estrutura Molecular , Tamanho da Partícula , Polímeros/síntese química , Polímeros/química , Propriedades de Superfície
11.
Mar Drugs ; 12(7): 3953-69, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24983639

RESUMO

This study was performed to evaluate the ability of N-(2-hydroxypropyl)-3-tri methylammonium chitosan chloride (HTCC), the cationically modified chitosan, to form biologically inactive complexes with unfractionated heparin and thereby blocking its anticoagulant activity. Experiments were carried out in rats in vivo and in vitro using the activated partial thromboplastin time (APTT) and prothrombin time (PT) tests for evaluation of heparin anticoagulant activity. For the first time we have found that HTCC effectively neutralizes anticoagulant action of heparin in rat blood in vitro as well as in rats in vivo. The effect of HTCC on suppression of heparin activity is dose-dependent and its efficacy can be comparable to that of protamine-the only agent used in clinic for heparin neutralization. HTCC administered i.v. alone had no direct effect on any of the coagulation tests used. The potential adverse effects of HTCC were further explored using rat experimental model of acute toxicity. When administered i.p. at high doses (250 and 500 mg/kg body weight), HTCC induced some significant dose-dependent structural abnormalities in the liver. However, when HTCC was administered at low doses, comparable to those used for neutralization of anticoagulant effect of heparin, no histopathological abnormalities in liver were observed.


Assuntos
Quitosana/análogos & derivados , Antagonistas de Heparina/farmacologia , Animais , Quitosana/farmacologia , Relação Dose-Resposta a Droga , Antagonistas de Heparina/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Tempo de Tromboplastina Parcial , Ratos , Ratos Wistar
12.
ACS Appl Mater Interfaces ; 16(5): 5426-5437, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38277775

RESUMO

Curcumin, a natural product with recognized antiviral properties, is limited in its application largely due to its poor solubility. This study presents the synthesis of water-soluble curcumin-poly(sodium 4-styrenesulfonate) (Cur-PSSNan) covalent conjugates. The antiflaviviral activity of conjugates was validated in vitro by using the Zika virus as a model. In the development of these water-soluble curcumin-containing derivatives, we used the macromolecules reported by us to also hamper viral infections. Mechanistic investigations indicated that the conjugates exhibited excellent stability and bioavailability. The curcumin and macromolecules in concerted action interact directly with virus particles and block their attachment to host cells, hampering the infection process.


Assuntos
Curcumina , Infecção por Zika virus , Zika virus , Humanos , Curcumina/farmacologia , Internalização do Vírus , Infecção por Zika virus/tratamento farmacológico , Solubilidade , Água
13.
Adv Healthc Mater ; : e2402191, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370656

RESUMO

Despite targeting different coagulation cascade sites, all Food and Drug Administration-approved anticoagulants present an elevated risk of bleeding, including potentially life-threatening intracranial hemorrhage. Existing studies have not thoroughly investigated the efficacy and safety of sulfonate polymers in animal models and fully elucidate the precise mechanisms by which these polymers act. The activity and safety of sulfonated di- and triblock copolymers containing poly(sodium styrenesulfonate) (PSSS), poly(sodium 2-acrylamido-2-methylpropanesulfonate) (PAMPS), poly(ethylene glycol) (PEG), poly(sodium methacrylate) (PMAAS), poly(acrylic acid) (PAA), and poly(sodium 11-acrylamidoundecanoate) (PAaU) blocks are synthesized and assessed. PSSS-based copolymers exhibit greater anticoagulant activity than PAMPS-based ones. Their activity is mainly affected by the total concentration of sulfonate groups and molecular weight. PEG-containing copolymers demonstrate a better safety profile than PAA-containing ones. The selected copolymer PEG47-PSSS32 exhibits potent anticoagulant activity in rodents after subcutaneous and intravenous administration. Heparin Binding Copolymer (HBC) completely reverses the anticoagulant activity of polymer in rat and human plasma. No interaction with platelets is observed. Selected copolymer targets mainly factor XII and fibrinogen, and to a lesser extent factors X, IX, VIII, and II, suggesting potential application in blood-contacting biomaterials for anticoagulation purposes. Further studies are needed to explore its therapeutic applications fully.

14.
ACS Omega ; 8(7): 6875-6883, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36844524

RESUMO

A series of poly(ethylene glycol)-block-poly(sodium 4-styrenesulfonate) (PEG-b-PSSNa) copolymers were synthesized, and their antiviral activity against Zika virus (ZIKV) was determined. The polymers inhibit ZIKV replication in vitro in mammalian cells at nontoxic concentrations. The mechanistic analysis revealed that the PEG-b-PSSNa copolymers interact directly with viral particles in a zipper-like mechanism, hindering their interaction with the permissive cell. The antiviral activity of the copolymers is well-correlated with the length of the PSSNa block, indicating that the copolymers' ionic blocks are biologically active. The blocks of PEG present in copolymers studied do not hinder that interaction. Considering the practical application of PEG-b-PSSNa and the electrostatic nature of the inhibition, the interaction between the copolymers and human serum albumin (HSA) was evaluated. The formation of PEG-b-PSSNa-HSA complexes in the form of negatively charged nanoparticles well-dispersed in buffer solution was observed. That observation is promising, given the possible practical application of the copolymers.

15.
J Med Chem ; 66(3): 1778-1789, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36657057

RESUMO

Unfractionated heparin (UFH) and enoxaparin (Enox) were substituted with a photoswitch (PS) showing quantitative trans-cis and cis-trans photoisomerizations. Long half-life of the cis photoisomer enabled comparison of the properties of heparins substituted with both PS photoisomers. Hydrodynamic diameter, Dh, of UFH-PS decreased upon trans-cis photoisomerization, the change being more pronounced for UFH-PS with a higher degree of substitution (DS), while Dh of Enox-PS did not significantly change. The anticoagulative properties of substituted heparins were significantly attenuated compared to non-substituted compounds. The interaction of UFH-PS with HSA, lysozyme, and protamine was studied with ITC. Under serum-free conditions, UFH-PS-trans with a high DS stimulated proliferation of murine fibroblasts, while UFH-PS-cis decreased the viability of these cells. Under serum conditions, both UFH-PS-cis and UFH-PS-trans decreased cell viability, the reduction for UFH-PS-cis being higher than that for UFH-PS-trans. Neither Enox-PS-trans nor Enox-PS-cis influenced the viability at concentrations prolonging aPTT, while at higher concentrations their cytotoxicity did not differ.


Assuntos
Enoxaparina , Heparina , Animais , Camundongos , Heparina/farmacologia , Resultado do Tratamento , Enoxaparina/farmacologia , Anticoagulantes
16.
Biomolecules ; 13(5)2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37238712

RESUMO

Despite the plethora of research that exists on recombinant human bone morphogenetic protein-2 and -7 (rhBMP-2 and rhBMP-7) and has been clinically approved, there is still a need to gain information that would allow for their more rational use in bone implantology. The clinical application of supra-physiological dosages of these superactive molecules causes many serious adverse effects. At the cellular level, they play a role in osteogenesis and cellular adhesion, migration, and proliferation around the implant. Therefore, in this work, we investigated the role of the covalent binding of rhBMP-2 and rhBMP-7 separately and in combination with ultrathin multilayers composed of heparin and diazoresin in stem cells. In the first step, we optimized the protein deposition conditions via quartz crystal microbalance (QCM). Then, atomic force microscopy (AFM) and enzyme-linked immunosorbent assay (ELISA) were used to analyze protein-substrate interactions. The effect of the protein binding on the initial cell adhesion, migration, and short-term expression of osteogenesis markers was tested. In the presence of both proteins, cell flattening and adhesion became more prominent, resulting in limited motility. However, the early osteogenic marker expression significantly increased compared to the single protein systems. The presence of single proteins resulted in the elongation of cells, which promoted their migration activity.


Assuntos
Heparina , Fator de Crescimento Transformador beta , Humanos , Heparina/farmacologia , Proteína Morfogenética Óssea 2/metabolismo , Compostos Azo/farmacologia , Osteogênese , Proteínas Recombinantes/metabolismo , Diferenciação Celular
17.
Mater Today Bio ; 22: 100763, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37600352

RESUMO

The battle against emerging viral infections has been uneven, as there is currently no broad-spectrum drug available to contain the spread of novel pathogens throughout the population. Consequently, the pandemic outbreak that occurred in early 2020 laid bare the almost empty state of the pandemic box. Therefore, the development of novel treatments with broad specificity has become a paramount concern in this post-pandemic era. Here, we propose copolymers of poly (sodium 2-(acrylamido)-2-methyl-1-propanesulfonate) (PAMPS) and poly (sodium 11-(acrylamido)undecanoate (AaU), both block (PAMPS75-b-PAaUn) and random (P(AMPSm-co-AaUn)) that show efficacy against a broad range of alpha and betacoronaviruses. Owing to their intricate architecture, these polymers exhibit a highly distinctive mode of action, modulating nano-mechanical properties of cells and thereby influencing viral replication. Through the employment of confocal and atomic force microscopy techniques, we discerned perturbations in actin and vimentin filaments, which correlated with modification of cellular elasticity and reduction of glycocalyx layer. Intriguingly, this process was reversible upon polymer removal from the cells. To ascertain the applicability of our findings, we assessed the efficacy and underlying mechanism of the inhibitors using fully differentiated human airway epithelial cultures, wherein near-complete abrogation of viral replication was documented. Given their mode of action, these polymers can be classified as biologically active nanomaterials that exploit a highly conserved molecular target-cellular plasticity-proffering the potential for truly broad-spectrum activity while concurrently for drug resistance development is minimal.

18.
Antiviral Res ; 213: 105604, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37054954

RESUMO

Herpes simplex virus type 1 (HSV-1) is a widespread human pathogen known to cause infections of diverse severity, ranging from mild ulceration of mucosal and dermal tissues to life-threatening viral encephalitis. In most cases, standard treatment with acyclovir is sufficient to manage the disease progression. However, the emergence of ACV-resistant strains drives the need for new therapeutics and molecular targets. HSV-1 VP24 is a protease indispensable for the assembly of mature virions and, as such, constitutes an interesting target for the therapy. In this study, we present novel compounds, KI207M and EWDI/39/55BF, that block the activity of VP24 protease and consequently inhibit HSV-1 infection in vitro and in vivo. The inhibitors were shown to prevent the egress of viral capsids from the cell nucleus and suppress the cell-to-cell spread of the infection. They were also proven effective against ACV-resistant HSV-1 strains. Considering their low toxicity and high antiviral potency, the novel VP24 inhibitors could provide an alternative for treating ACV-resistant infections or a drug to be used in combined, highly effective therapy.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Humanos , Peptídeo Hidrolases , Antivirais/uso terapêutico , Aciclovir/farmacologia , Herpes Simples/tratamento farmacológico , Farmacorresistência Viral
19.
J Mater Sci Mater Med ; 23(8): 1991-2000, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22569736

RESUMO

Novel polymeric hydrogel scaffolds for corneal epithelium cell culturing based on blends of chitosan with some other biopolymers such as hydroxypropylcellulose, collagen and elastin crosslinked with genipin, a natural substance, were prepared. Physicochemical and biomechanical properties of these materials were determined. The in vitro cell culture experiments with corneal epithelium cells have indicated that a membrane prepared from chitosan-collagen blend (Ch-Col) provided the regular stratified growth of the epithelium cells, good surface covering and increased number of the cell layers. Ch-Col membranes are therefore the most promising material among those studied. The performance of Ch-Col membranes is comparable with that of the amniotic membrane which is currently recommended for clinical applications.


Assuntos
Quitosana/química , Epitélio Corneano/citologia , Epitélio Corneano/crescimento & desenvolvimento , Hidrogéis/química , Iridoides/química , Membranas Artificiais , Alicerces Teciduais , Células Cultivadas , Reagentes de Ligações Cruzadas , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Engenharia Tecidual/instrumentação
20.
Przegl Lek ; 69(10): 992-7, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-23421077

RESUMO

The cornea is a transparent front layer of the eye. It functions like a window that controls and focuses the light entering into the eye. The cornea contributes to 65-75% of the eye's total focusing power and it acts as a physical barrier against pathogenic microorganisms, dirt and other noxious physical factors. The corneal tissue is arranged in five basic layers. The outermost layer (epithelium) is made up of highly regenerative cells that allow for quick healing of superficial injuries. Eye infections, diseases, or mechanical injury can harm corneal epithelium and cause blindness. Under certain circumstances, to prevent that, it is recommended to perform complete corneal transplantation. However, due to lack of sufficient number of donors, researchers are searching for alternative solutions.. Regeneration of epidermal tissue can restore and ensure normal functioning of cornea. For that purpose proper grafts are needed. The goal of current research was to develop the material for scaffold preparation providing optimal conditions for the epithelium cornea cell culturing and to determine its chemical, physical, and biological properties. The scaffolds, which could be applied in ophthalmology should fulfill a lot of requirements, among them such as biocompatibility, biodegradability, restorability, non-toxicity. They should also have adequate mechanical strength, flexibility and porosity. The aim of this work was to synthesize and to determine the properties of polymeric material for ophthalmic surgery applications. A hydrogel scaffold in the form of membrane was obtained from chitosan - natural, biocompatible, biologically inert, stable in the natural environmental and antibacterial polysaccharide derived from chitin. Biodegradable chitosan films containing keratin were crosslinked with genipin - a naturally occurring and nontoxic agent. In this study we present physicochemical characterization of the scaffolds. Porosity, contact angle and swelling ratio (at different pH) were determined. The optical microscope technique was used to visualize the microstructure of the scaffolds. Atomic force microscopy (AFM) measurements revealed the topography of the surfaces of membranes. The biological tests have shown that epithelial cells seeded on the membranes proliferated efficiently.


Assuntos
Quitosana/química , Epitélio Corneano/citologia , Regeneração Tecidual Guiada/métodos , Queratinas/química , Membranas Artificiais , Engenharia Tecidual/métodos , Alicerces Teciduais , Materiais Biocompatíveis , Reagentes de Ligações Cruzadas , Epitélio Corneano/fisiologia , Epitélio Corneano/cirurgia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Teste de Materiais , Modelos Biológicos , Regeneração
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