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1.
Exp Eye Res ; 235: 109612, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37580001

RESUMO

The harderian gland (HG) is a gland located at the base of the nictating membrane and fills the inferomedial aspect of the orbit in rodents. It is under the influence of the hypothalamic-pituitary-gonadal axis and, because of its hormone receptors, it is a target tissue for prolactin (PRL) and sex steroid hormones (estrogen and progesterone). In humans and murine, the anterior surface of the eyes is protected by a tear film synthesized by glands associated with the eye. In order to understand the endocrine changes caused by hyperprolactinemia in the glands responsible for the formation of the tear film, we used an animal model with metoclopramide-induced hyperprolactinemia (HPRL). Given the evidences that HPRL can lead to a process of cell death and tissue fibrosis, the protein expression of small leucine-rich proteoglycans (SLRPs) was analyzed through immunohistochemistry in the HG of the non- and the pregnant female mice with hyperprolactinemia. The SRLPs are related to collagen fibrillogenesis and they participate in pro-apoptotic signals. Our data revealed that high prolactin levels and changes in steroid hormones (estrogen and progesterone) can lead to an alteration in the amount of collagen, and in the structure of type I and III collagen fibers through changes in the amounts of lumican and decorin, which are responsible for collagen fibrillogenesis. This fact can lead to the impaired functioning of the HG by excessive apoptosis in the HG of the non- and the pregnant female mice with HPRL and especially in the HG of pregnancy-associated hyperprolactinemia.


Assuntos
Glândula de Harder , Hiperprolactinemia , Gravidez , Humanos , Camundongos , Feminino , Animais , Proteoglicanas/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Hiperprolactinemia/induzido quimicamente , Hiperprolactinemia/metabolismo , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Decorina/metabolismo , Prolactina/efeitos adversos , Prolactina/análise , Prolactina/metabolismo , Progesterona , Glândula de Harder/metabolismo , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Estrogênios/efeitos adversos , Estrogênios/análise , Estrogênios/metabolismo
2.
Science ; 378(6623): 931, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36454828

RESUMO

Last month in Egypt at the United Nations Climate Change Conference, Brazil's president-elect Luiz Inácio Lula da Silva reaffirmed his pledge to make Brazil a global leader in addressing climate change and deforestation. However, when Lula takes the reins on 1 January, he will step into a situation that is quite different from when last he was president (2003-2010). At that time, he prioritized science and education in all government actions and guided Brazil to a prosperous social state and sustainable economy. This time, he will face a much different local and global scenario. The world is still going through an unprecedented health crisis, and like other countries, Brazil needs to establish new ways of tackling the consequential social, educational, environmental, and economic problems. This will be especially challenging given that since 2016, the country has taken the opposite direction of most governments, cutting investments in education at all levels and in science, technology, and innovation (ST&I). The question is how Lula can immediately address the serious poverty and hunger crisis in Brazil while also restoring the environment and a competitive and equitable economy to the country.

3.
ACS Omega ; 7(28): 24461-24467, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35874203

RESUMO

Heparan sulfate (HS), a sulfated linear carbohydrate that decorates the cell surface and extracellular matrix, is ubiquitously distributed throughout the animal kingdom and represents a key regulator of biological processes and a largely untapped reservoir of potential therapeutic targets. The temporal and spatial variations in the HS structure underpin the concept of "heparanome" and a complex network of HS binding proteins. However, despite its widespread biological roles, the determination of direct structure-to-function correlations is impaired by HS chemical heterogeneity. Attempts to correlate substitution patterns (mostly at the level of sulfation) with a given biological activity have been made. Nonetheless, these do not generally consider higher-level conformational effects at the carbohydrate level. Here, the use of NMR chemical shift analysis, NOEs, and spin-spin coupling constants sheds new light on how different sulfation patterns affect the polysaccharide backbone geometry. Furthermore, the substitution of native O-glycosidic linkages to hydrolytically more stable S-glycosidic forms leads to observable conformational changes in model saccharides, suggesting that alternative chemical spaces can be accessed and explored using such mimetics. Employing a series of systematically modified heparin oligosaccharides (as a proxy for HS) and chemically synthesized O- and S-glycoside analogues, the chemical space occupied by such compounds is explored and described.

4.
Nanoscale ; 14(19): 7350-7363, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35535683

RESUMO

Engineered nanoparticles approaching the cell body will first encounter and interact with cell-surface glycosaminoglycans (GAGs) before reaching the plasma membrane and becoming internalized. However, how surface GAGs may regulate the cellular entry of nanoparticles remains poorly understood. Herein, it is shown that the surface GAGs of Chinese hamster ovary cells perform as a charge-based barrier against the cellular internalization of anionic polystyrene nanoparticles (PS NPs). In contrast, cationic PS NPs interact favorably with the surface GAGs and thereby are efficiently internalized. Anionic PS NPs eventually reaching the plasma membrane bind to scavenger receptors and are endocytosed by clathrin-mediated and lipid raft/cholesterol-dependent mechanisms, whereas cationic PS NPs are primarily internalized via clathrin-mediated endocytosis and macropinocytosis. Upon the enzymatic shedding of surface GAGs, the uptake of anionic PS NPs increases while that of cationic PS NPs is dramatically reduced. Interestingly, the diminished uptake of cationic PS NPs is observed only when heparan sulfate, but not chondroitin sulfate, is cleaved from the cell surface. Heparan sulfate therefore serves as anchors/first receptors to facilitate the cellular entry of cationic PS NPs. These findings contribute to advance the basic science of nanoparticle endocytosis while also having important implications for the use of engineered nanocarriers as intracellular drug-delivery systems.


Assuntos
Nanopartículas , Poliestirenos , Animais , Células CHO , Cátions , Membrana Celular/metabolismo , Clatrina/metabolismo , Cricetinae , Cricetulus , Endocitose , Glicosaminoglicanos , Heparitina Sulfato/metabolismo , Nanopartículas/metabolismo
5.
Gynecol Endocrinol ; 38(2): 181-185, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34463181

RESUMO

AIMS: To evaluate the concentration of hyaluronan acid and proliferation/cellular death in mammary gland of ovariectomized female rat after estroprogestative therapy. MATERIALS AND METHODS: Forty ovariectomized female rats were divided into four groups with 10 animals/each: OG (vehicle); EG: (Estradiol, 7 days of treatment), PG (Progesterone acetate, 23 days of treatment), and EPG: (Estradiol, 7 days of treatment, and next Progesterone acetate, 23 days of treatment). Twenty-four hours after the last treatment, all animals were euthanized, the mammary gland removed, then, a fragment was immersed in acetone to quantifying of the hyaluronan acid biochemical method (ELISA-Like fluorometric assay), and a fragment fixed for 24 h in 10% formaldehyde in phosphate-buffered saline (PBS) processed for immunohistochemistry method for detection of the cell marker proliferation (Ki67) and cellular marker death by DNA fragmentation the TUNEL method. RESULTS: The estradiol-treatment alone (EG) or associated with progesterone (EPG) affected the concentration of hyaluronan acid, increased cell proliferation, and decreased cell death compared to OG and PG (p < .05) in the mammary tissue. CONCLUSIONS: Our results suggest that the excessive reduction of HA in mammary tissue, as occurred with progesterone treatment, can lead to a breakdown of the extracellular matrix. These changes may be indicative of mammary pathology such as the development of tumor.


Assuntos
Estradiol , Ácido Hialurônico , Glândulas Mamárias Animais , Progesterona , Animais , Morte Celular , Proliferação de Células , Estradiol/farmacologia , Feminino , Ácido Hialurônico/análise , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/patologia , Progesterona/farmacologia , Ratos
7.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202190

RESUMO

Background: The disease caused by hepatitis C virus (HCV) is asymptomatic, silent, and progressive liver disease. In HCV-infected patients the increase in serum HA is associated with the development of hepatic fibrosis and disease progression. Methods: HCV-RNA detection was performed in all serological samples of blood donors that tested positive using HCV Ultra ELISA. Determination of hyaluronan (HA) was performed in positive HCV samples using ELISA-like fluorometric method. The HA content was compared to HCV viral load, genotype of the virus, liver fibrosis as well as ALT and GGT liver biomarkers. Results: Persistently normal ALT (<40 U/L) and GGT (<50 U/L) serum levels were detected in 75% and 69% of the HCV-Infected blood donors, respectively. Based on ROC analysis, the HA value < 34.2 ng/mL is an optimal cut-off point to exclude HCV viremia (specificity = 91%, NPV = 99%). Applying HA value ≥34.2 ng/mL significant liver fibrosis (≥F2) can be estimated in 46% of the HCV-infected blood donors. HA serum level (≥34.2 ng/mL) associated with a high ALT level (>40 U/mL) can correctly identify HCV infection and probable liver fibrosis (sensitivity = 96% and specificity = 90%) in asymptomatic blood donors. Conclusions: A high level of HA (≥34.2 ng/mL) in association with ALT (≥40 U/L) in serum can provide a good clinical opportunity to detect HCV-infected asymptomatic persons that potentially require a liver biopsy confirmation and antiviral treatment to prevent the development of advanced liver fibrosis or cirrhosis.


Assuntos
Doadores de Sangue , Hepacivirus/metabolismo , Hepatite C/sangue , Hepatite C/diagnóstico , Ácido Hialurônico/sangue , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/genética , Humanos , Cirrose Hepática/genética , Masculino , Pessoa de Meia-Idade
8.
Carbohydr Polym ; 255: 117477, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436240

RESUMO

The cell surface and extracellular matrix polysaccharide, heparan sulfate (HS) conveys chemical information to control crucial biological processes. HS chains are synthesized in a non-template driven process mainly in the Golgi apparatus, involving a large number of enzymes capable of subtly modifying its substitution pattern, hence, its interactions and biological effects. Changes in the localization of HS-modifying enzymes throughout the Golgi were found to correlate with changes in the structure of HS, rather than protein expression levels. Following BFA treatment, the HS-modifying enzymes localized preferentially in COPII vesicles and at the trans-Golgi. Shortly after heparin treatment, the HS-modifying enzyme moved from cis to trans-Golgi, which coincided with increased HS sulfation. Finally, it was shown that COPI subunits and Sec24 gene expression changed. Collectively, these findings demonstrate that knowledge of the ER-Golgi dynamics of HS-modifying enzymes via vesicular trafficking is a critical prerequisite for the complete delineation of HS biosynthesis.


Assuntos
Vesículas Revestidas pelo Complexo de Proteína do Envoltório/enzimologia , Retículo Endoplasmático/enzimologia , Complexo de Golgi/enzimologia , Heparitina Sulfato/biossíntese , Transporte Biológico/efeitos dos fármacos , Brefeldina A/farmacologia , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/genética , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Retículo Endoplasmático/química , Retículo Endoplasmático/efeitos dos fármacos , Regulação da Expressão Gênica , Complexo de Golgi/química , Complexo de Golgi/efeitos dos fármacos , Heparina/farmacologia , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Plasmídeos/química , Plasmídeos/metabolismo , Cultura Primária de Células , Transfecção , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
9.
Glycoconj J ; 38(1): 35-43, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33411076

RESUMO

Cells undergoing hypoxia experience intense cytoplasmic calcium (Ca2+) overload. High concentrations of intracellular calcium ([Ca2+]i) can trigger cell death in the neural tissue, a hallmark of stroke. Neural Ca2+ homeostasis involves regulation by the Na+/Ca2+ exchanger (NCX). Previous data published by our group showed that a product of the enzymatic depolymerization of heparin by heparinase, the unsaturated trisulfated disaccharide (TD; ΔU, 2S-GlcNS, 6S), can accelerate Na+/Ca2+ exchange via NCX, in hepatocytes and aorta vascular smooth muscle cells. Thus, the objective of this work was to verify whether TD could act as a neuroprotective agent able to prevent neuronal cell death by reducing [Ca2+]i. Pretreatment of N2a cells with TD reduced [Ca2+]i rise induced by thapsigargin and increased cell viability under [Ca2+]I overload conditions and in hypoxia. Using a murine model of stroke, we observed that pretreatment with TD decreased cerebral infarct volume and cell death. However, when mice received KB-R7943, an NCX blocker, the neuroprotective effect of TD was abolished, strongly suggesting that this neuroprotection requires a functional NCX to happen. Thus, we propose TD-NCX as a new therapeutic axis for the prevention of neuronal death induced by [Ca2+]i overload.


Assuntos
Dissacarídeos/farmacologia , Heparina/análogos & derivados , AVC Isquêmico/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Animais , Cálcio/metabolismo , Morte Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dissacarídeos/química , Heparina/química , Heparina/farmacologia , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/química , Tapsigargina/farmacologia , Tioureia/análogos & derivados , Tioureia/farmacologia
10.
ACS Appl Bio Mater ; 4(8): 6488-6501, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35006908

RESUMO

The cytotoxic mode of action of four antimicrobial peptides (AMPs) (gomesin, tachyplesin, protegrin, and polyphemusin) against a HeLa cell tumor model is discussed. A study of cell death by AMP stimulation revealed some similarities, including annexin-V externalization, reduction of mitochondrial potential, insensitivity against inhibitors of cell death, and membrane permeabilization. Evaluation of signaling proteins and gene expression that control cell death revealed wide variation in the responses to AMPs. However, the ability to cross cell membranes emerged as an important characteristic of AMP-dependent cell death, where endocytosis mediated by dynamin is a common mechanism. Furthermore, the affinity between AMPs and glycosaminoglycans (GAGs) and GAG participation in the cytotoxicity of AMPs were verified. The results show that, despite their primary and secondary structure homology, these peptides present different modes of action, but endocytosis and GAG participation are an important and common mechanism of cytotoxicity for ß-hairpin peptides.


Assuntos
Peptídeos Antimicrobianos , Glicosaminoglicanos , Humanos , Morte Celular , Endocitose , Células HeLa
11.
Thromb Haemost ; 120(12): 1700-1715, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33368089

RESUMO

The dependence of development and homeostasis in animals on the interaction of hundreds of extracellular regulatory proteins with the peri- and extracellular glycosaminoglycan heparan sulfate (HS) is exploited by many microbial pathogens as a means of adherence and invasion. Heparin, a widely used anticoagulant drug, is structurally similar to HS and is a common experimental proxy. Exogenous heparin prevents infection by a range of viruses, including S-associated coronavirus isolate HSR1. Here, we show that heparin inhibits severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) invasion of Vero cells by up to 80% at doses achievable through prophylaxis and, particularly relevant, within the range deliverable by nebulisation. Surface plasmon resonance and circular dichroism spectroscopy demonstrate that heparin and enoxaparin, a low-molecular-weight heparin which is a clinical anticoagulant, bind and induce a conformational change in the spike (S1) protein receptor-binding domain (S1 RBD) of SARS-CoV-2. A library of heparin derivatives and size-defined fragments were used to probe the structural basis of this interaction. Binding to the RBD is more strongly dependent on the presence of 2-O or 6-O sulfate groups than on N-sulfation and a hexasaccharide is the minimum size required for secondary structural changes to be induced in the RBD. It is likely that inhibition of viral infection arises from an overlap between the binding sites of heparin/HS on S1 RBD and that of the angiotensin-converting enzyme 2. The results suggest a route for the rapid development of a first-line therapeutic by repurposing heparin and its derivatives as antiviral agents against SARS-CoV-2 and other members of the Coronaviridae.


Assuntos
Anticoagulantes/farmacologia , Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Enoxaparina/farmacologia , Heparina/farmacologia , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , Anticoagulantes/uso terapêutico , Antivirais/uso terapêutico , Chlorocebus aethiops , Enoxaparina/uso terapêutico , Heparina/uso terapêutico , Humanos , Simulação de Dinâmica Molecular , Nebulizadores e Vaporizadores , Ligação Proteica , Conformação Proteica , Domínios Proteicos/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Relação Estrutura-Atividade , Células Vero , Internalização do Vírus
12.
Chem Phys Lipids ; 227: 104875, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31952936

RESUMO

Trastuzumab (Tmab), an antibody for breast cancer, was incorporated in Langmuir monolayers with different lipidic compositions to investigate the drug action in lipidic interfaces of pharmaceutical interest. Tmab caused all lipid films to expand as confirmed with by surface pressure-area isotherm, proving its incorporation. It also affected the compressional and structural properties as observed by in-plane elasticity curves and polarization modulation reflection-absorption infrared spectroscopy (PM-IRRAS), respectively. Although Tmab did not change significantly the compressional modulus for dipalmitoylphosphatidylcholine (DPPC) monolayers, it decreased it for the mixtures of DPPC with cholesterol. In contrast, for dipalmitoylphosphoethanolamine (DPPE), Tmab increased the compressional modulus for both monolayers, pure DPPE or mixed with cholesterol. While Brewster Angle Microscopy showed discrete distinctive morphological patterns for the monolayers investigated, PM-IRRAS showed that Tmab caused an increased number of gauche conformers related to the CH2 stretching mode for the lipid acyl chains, suggesting molecular disorder. Furthermore, the antibody kept the ß-sheet structure of the polypeptide backbone adsorbed at the lipid monolayers although the secondary conformation altered according to the film composition at the air-water interface. As a result, the results suggest that the membrane lipid profile affects the adsorption of Tmab at lipid monolayers, which can be important for the incorporation of this drug in lipidic supramolecular systems like in liposomes for drug delivery and in biomembranes.


Assuntos
Trastuzumab/química , Lipossomas Unilamelares/química , 1,2-Dipalmitoilfosfatidilcolina/química , Adsorção , Ar , Colesterol/química , Elasticidade , Fosforilcolina/química , Espectrofotometria Infravermelho , Propriedades de Superfície , Lipossomas Unilamelares/metabolismo , Água/química
13.
Molecules ; 24(16)2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31426507

RESUMO

Nowadays, pharmaceutical heparin is purified from porcine and bovine intestinal mucosa. In the past decade there has been an ongoing concern about the safety of heparin, since in 2008, adverse effects associated with the presence of an oversulfated chondroitin sulfate (OSCS) were observed in preparations of pharmaceutical porcine heparin, which led to the death of patients, causing a global public health crisis. However, it has not been clarified whether OSCS has been added to the purified heparin preparation, or whether it has already been introduced during the production of the raw heparin. Using a combination of different analytical methods, we investigate both crude and final heparin products and we are able to demonstrate that the sulfated contaminants are intentionally introduced in the initial steps of heparin preparation. Furthermore, the results show that the oversulfated compounds are not structurally homogeneous. In addition, we show that these contaminants are able to bind to cells in using well known heparin binding sites. Together, the data highlights the importance of heparin quality control even at the initial stages of its production.


Assuntos
Anticoagulantes/isolamento & purificação , Sulfatos de Condroitina/isolamento & purificação , Contaminação de Medicamentos , Heparina/isolamento & purificação , Animais , Anticoagulantes/química , Bovinos , Sulfatos de Condroitina/química , Heparina/química , Heparina Liase/química , Humanos , Hidrólise , Mucosa Intestinal/química , Espectroscopia de Ressonância Magnética , Polissacarídeo-Liases/química , Controle de Qualidade , Suínos
14.
Carbohydr Polym ; 222: 115031, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320064

RESUMO

The detailed structure of a further Chondroitin Sulfate from Litopenaeus vannamei shrimp (sCS) is described. The backbone structure was established by 1H/13C NMR, which identified 3-O-sulfated GlcA, 4-O-sulfated GalNAc, 6-O-sulfated GalNAc, and 4,6-di-O-sulfated GalNAc residues. GlcA is linked to GalNAc 4,6 di S and GlcA 3S is linked to GalNAc 4S, GalNAc 4,6 di-S and GalNAc6S residues. The anticoagulant properties of this sCS were evaluated by activated partial thromboplastin time, anti-IIa, anti-Xa and anti-heparin cofactor II-mediated activities, and sCS failed to stabilise antithrombin in a fluoresence shift assay. The anti-inflammatory effect of sCS was explored using a model of acute peritonitis, followed by leukocyte count and measurement of the cytokines, IL-1ß, IL-6 and TNF-α. The compound showed low clotting effects, but high anti-IIa activity and HCII-mediated thrombin inhibition. Its anti-inflammatory effect was shown by leukocyte recruitment inhibition and a decrease in pro-inflammatory cytokine levels. Although the biological role of sCS remains unknown, its properties indicate that it is suitable for studies of multi-potent molecules obtained from natural sources.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antitrombinas/uso terapêutico , Sulfatos de Condroitina/uso terapêutico , Inflamação/tratamento farmacológico , Penaeidae/química , Peritonite/tratamento farmacológico , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antitrombinas/química , Antitrombinas/isolamento & purificação , Sulfatos de Condroitina/química , Sulfatos de Condroitina/isolamento & purificação , Citocinas/metabolismo , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peso Molecular , Óxido Nítrico/metabolismo , Peritonite/induzido quimicamente , Células RAW 264.7 , Ratos Wistar
15.
Biochim Biophys Acta Biomembr ; 1861(10): 182992, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31129115

RESUMO

Trastuzumab (Tmab) is a monoclonal antibody administered as targeted therapy for HER2-positive breast cancer whose molecular interactions at the HER2 receptor microenvironment are not completely clarified yet. This paper describes the influence of Tmab in the molecular organization of films of biological-relevant molecules at the air water interface. For that, we spread components of tumorigenic and non-tumorigenic cells directly on the air-water interface. The physicochemical properties of the films were investigated with surface pressure-area isotherms and Brewster angle microscopy, and distinction between the cellular lines with higher or lower amount of HER2 could be detected based on the physicochemical properties of the interfacial films. The systems organized at the air-water interface were transferred to solid supports as Langmuir-Blodgett films and the nano-scale morphology investigated with atomic force microscopy. The overall results related to Tmab interacting with the films lead to the conclusion that Tmab tends to condense rich-HER2 films, causing irregular dimerization of the receptor protein, changing the membrane topography of the films, with formation of phases with different levels of reflectivity and aggregation morphology, and finally revealing that the interaction of the antibody with proteo-lipidic biointerfaces is modulated by the film composition. We believe that novel perspectives concerning the molecular interactions in the plasma membrane microenvironment through Langmuir monolayers can be obtained from this work in order to enhance the Tmab-based cancer therapy.


Assuntos
Membrana Celular/efeitos dos fármacos , Trastuzumab/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Feminino , Humanos , Bicamadas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Lipídeos , Microscopia de Força Atômica , Modelos Biológicos , Receptor ErbB-2/metabolismo , Propriedades de Superfície , Trastuzumab/metabolismo
16.
Int J Biol Macromol ; 118(Pt B): 1470-1478, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29964117

RESUMO

In this present study, the anti-IIa activity and the antitumor properties of a hybrid heparin/heparan sulfate-like compound (sH/HS) from Litopenaeus vannamei shrimp heads are related. In addition to inhibiting 90.7% of thrombin activity at the lowest tested concentration (0.5 µg/mL), sH/HS compound stimulated the synthesis of antithrombotic heparan sulfate by endothelial cells in a dose-dependent manner. In vitro experiments demonstrated that the molecule from shrimp displayed a potent anti-angiogenic effect, reducing over 80% of the tubular structures formation at 50 and 100 µg/mL. In addition, sH/HS compound was able to inhibit the migration of B16F10 cells at all tested concentrations without affecting the cell viability. Although the studied compound had no effect on the proliferation of such cells during a period of 24 h, it had a significant long-term anti-proliferative effect, reducing about 80% of colony formation and anchorage-independent growth at 50 and 100 µg/mL concentrations. When its effectiveness was tested in vivo, it was demonstrated that sH/HS promoted a reduction of more than 90% of tumor growth. In the context of thromboembolic disorders associated with cancer, such findings make the sH/HS compound an excellent target for studies on inhibiting of development and tumor progression, and the prevention of coagulopathies.


Assuntos
Heparina/química , Heparitina Sulfato/química , Heparitina Sulfato/farmacologia , Penaeidae/química , Protrombina/antagonistas & inibidores , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Coelhos
17.
Front Cardiovasc Med ; 5: 67, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29930947

RESUMO

Background: Blockage of the Na+/Ca2+ exchanger (NCX) is used to determine the role of NCX in arrhythmogenesis. Trisulfated heparin disaccharide (TD) and Low Molecular Weight Heparins (LMWHs) can directly interact with the NCX and accelerate its activity. Objective: In this work, we investigated the antiarrhythmic effect of heparin oligosaccharides related to the NCX activity. Methods: The effects of heparin oligosaccharides were tested on the NCX current (patch clamping) and intracellular calcium transient in rat cardiomyocytes. The effects of heparin oligosaccharides were further investigated in arrhythmia induced in isolated rat atria and rats in vivo. Results: The intracellular Ca2+ concentration decreases upon treatment with either enoxaparin or ardeparin. These drugs abolished arrhythmia induction in isolated atria. The NCX antagonist KB-R7943 abolished the enoxaparin or ardeparin antiarrhythmic effects in isolated atria. In the in vivo measurements, injection of TD 15 min both before coronary occlusion or immediately after reperfusion, significantly prevented the occurrence of reperfusion-induced arrhythmias (ventricular arrhythmia and total AV block) and reduced the lethality rate. The patch clamping experiments showed that, mechanistically, TD increases the forward mode NCX current. Conclusion: Together, the data shows that heparin oligosaccharides may constitute a new class of antiarrhythmic drug that acts by accelerating the forward mode NCX under calcium overload.

18.
Arq Bras Cir Dig ; 31(1): e1352, 2018 Jun 21.
Artigo em Inglês, Português | MEDLINE | ID: mdl-29947686

RESUMO

BACKGROUND: Intracellular calcium overload is known to be a precipitating factor of pancreatic cell injury in acute pancreatitis (AP). Intracellular calcium homeostasis depends of Plasmatic Membrane Calcium ATPase (PMCA), Sarcoplasmic Endothelial Reticulum Calcium ATPase 2 (SERCA 2) and the Sodium Calcium Exchanger (NCX1). The antioxidant melatonin (Mel) and Trisulfate Disaccharide (TD) that accelerates NCX1 action could reduce the cell damage determined by the AP. AIM: To evaluate m-RNA expressions of SERCA2 and NCX1 in acute pancreatitis induced by sodium taurocholate in Wistar rats pre-treated with melatonin and/or TD. METHODS: Wistar rats were divided in groups: 1) without AP; 2) AP without pre-treatment; 3) AP and Melatonin; 4) AP and TD; 5) AP and Melatonin associated to TD. Pancreatic tissue samples were collected for detection of SERCA2 and NCX1 m-R NA levels by polymerase chain reaction (PCR). RESULTS: Increased m-RNA expression of SERCA2 in the melatonin treated group, without increase of m-RNA expression of the NCX1. The TD did not affect levels of SERCA2 and NCX1 m-RNA expressions. The combined melatonin and TD treatment reduced the m-RNA expression of SERCA2. CONCLUSIONS: The effect of melatonin is restricted to increased m-RNA expression of SERCA2. Although TD does not affect gene expression, its action in accelerating calcium exchanger function can explain the slightest expression of SERCA2 m-RNA when associated with Melatonin, perhaps by a joint action of drugs with different and but possibly complementary mechanisms.


Assuntos
Citoproteção/genética , Pancreatite/genética , RNA Mensageiro/biossíntese , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Trocador de Sódio e Cálcio/genética , Doença Aguda , Animais , Dissacarídeos/farmacologia , Modelos Animais de Doenças , Masculino , Melatonina/farmacologia , Pancreatite/induzido quimicamente , Ratos , Ratos Wistar , Ácido Taurocólico/administração & dosagem
19.
Carbohydr Polym ; 183: 192-200, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29352874

RESUMO

The occurrence of a natural and unmodified highly sulfated chondroitin sulfate from Litopenaeus vannamei heads (sCS) is herein reported. Its partial digestion by Chondroitinases AC and ABC together with its electrophoretic migration profile revealed it as a highly sulfated chondroitin sulfate despite its average molecular weight being similar to CSA. Using orthogonal 1D/2D NMR experiments, the anomeric signals (δ 4.62/106.0) corresponding to unusual 2,3-di-O-Sulfo-GlcA (∼36%), U33S (δ 4.42/84.1, ∼63%) and U22S (4.12/80.1, ∼50%) substitutions were confirmed. In addition, non-sulfated GlcA (δ 4.5/106.3) linked to 4-O- (A14S, 36%) or 6-O-Sulfo (A16S, 28%) GalNAc (δ 4.64/103.5) was observed. Although the biological role of sCS in shrimp is unknown, its influence on hemostasis was also demonstrated. The sCS identification brings to light new questions about the hierarchical model of GAGs biosynthesis and contributes to the better understanding of the subtle relationship between GAGs structure and function.


Assuntos
Anticoagulantes/química , Sulfatos de Condroitina/química , Decápodes/química , Ácido Glucurônico/química , Animais , Anticoagulantes/farmacologia , Células Cultivadas , Sulfatos de Condroitina/farmacologia , Hemostasia/efeitos dos fármacos , Masculino , Coelhos , Ratos , Ratos Wistar
20.
Gynecol Endocrinol ; 34(1): 64-68, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28762851

RESUMO

It was to evaluate the concentration of sulfate glycosaminoglycans (GAG) in mammary tissue of the young and adult female rats and ovariectomized females rats after hormonal stimulation. For this purpose, 60 female rats were divided into six groups with 10 animals/each: nonovariectomized groups: G1 (5 months), and G2 (15 months) and ovariectomized groups: OG (vehicle); EG: (estradiol, 7 days of treatment), PG (progesterone acetate, 23 days of treatment) and EPG: (estradiol (7 days of treatment) and next progesterone acetate (23 days of treatment). Twenty-four hours after the last treatment, all animals were euthanized, the mammary tissue removed, processed for biochemical evaluation and quantification of the GAG. The comparison between groups showed that the concentration dermatan sulfate (DS) G1 was lower compared to G2, OG, EG (p < .05) and G2 was lower compared to OG (p < .05), and OG was higher compared to EG, GP, EPG (p < .05); and heparan sulfate (HS) G1 was higher compared to G2 (p < .05), and G2 was higher compared to OG, EP, PG and EPG (p < .05). These changes in the extracellular matrix might explain, at least in part, hormonal influence about sulfated glycosaminoglycans in response to physiological state/age, and in response to hormonal treatment in the mammary tissues.


Assuntos
Envelhecimento/metabolismo , Estradiol/administração & dosagem , Glicosaminoglicanos/análise , Glândulas Mamárias Animais/química , Progesterona/administração & dosagem , Animais , Dermatan Sulfato/análise , Matriz Extracelular/fisiologia , Feminino , Heparitina Sulfato/análise , Glândulas Mamárias Animais/efeitos dos fármacos , Ovariectomia , Ratos
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