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1.
Pharmaceuticals (Basel) ; 16(10)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37895872

RESUMO

Ascidians are marine invertebrates that synthesize sulfated glycosaminoglycans (GAGs) within their viscera. Ascidian GAGs are considered analogues of mammalian GAGs and possess great potential as bioactive compounds, presenting antitumoral and anticoagulant activity. Due to its worldwide occurrence and, therefore, being a suitable organism for large-scale mariculture in many marine environments, our main objectives are to study Microcosmus exasperatus GAGs regarding composition, structure, and biological activity. We also aim to develop efficient protocols for sulfated polysaccharides extraction and purification for large-scale production and clinical applications. GAGs derived from M. exasperatus viscera were extracted by proteolytic digestion, purified by ion-exchange liquid chromatography, and characterized by agarose gel electrophoresis and enzymatic treatments. Anticoagulant activity was evaluated by APTT assays. Antitumoral activity was assessed in an in vitro model of tumor cell culture using MTT, clonogenic, and wound healing assays, respectively. Our results show that M. exasperatus presents three distinct polysaccharides; among them, two were identified: a dermatan sulfate and a fucosylated dermatan sulfate. Antitumoral activity was confirmed for the total polysaccharides (TP). While short-term incubation does not affect tumor cell viability at low concentrations, long-term TP incubation decreases LLC tumor cell growth/proliferation at different concentrations. In addition, TP decreased tumor cell migration at different concentrations. In conclusion, we state that M. exasperatus presents great potential as an alternative GAG source, producing compounds with antitumoral properties at low concentrations that do not possess anticoagulant activity and do not enhance other aspects of malignancy, such as tumor cell migration. Our perspectives are to apply these molecules in future preclinical studies for cancer treatment as antitumoral agents to be combined with current treatments to potentiate therapeutic efficacy.

2.
Molecules ; 27(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35208981

RESUMO

Phenolic compounds (PCs) present in foods are associated with a decreased risk of developing inflammatory diseases. The aim of this study was to extract and characterize PCs from craft beer powder and evaluate their potential benefits in an experimental model of inflammatory bowel disease (IBD). PCs were extracted and quantified from pure beer samples. BALB/c mice received either the beer phenolic extract (BPE) or beer powder fortified with phenolic extract (BPFPE) of PCs daily for 20 days by gavage. Colon samples were collected for histopathological and immunohistochemical analyses. Dextran sodium sulfate (DSS)-induced mice lost more weight, had reduced colon length, and developed more inflammatory changes compared with DSS-induced mice treated with either BPE or BPFPE. In addition, in DSS-induced mice, the densities of CD4- and CD11b-positive cells, apoptotic rates, and activation of NF-κB and p-ERK1/2 MAPK intracellular signaling pathways were higher in those treated with BPE and BPFPE than in those not treated. Pretreatment with the phenolic extract and BPFPE remarkably attenuated DSS-induced colitis. The protective effect of PCs supports further investigation and development of therapies for human IBD.


Assuntos
Cerveja , Colite , Animais , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colite/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pós , Dodecilsulfato de Sódio/toxicidade
3.
Sci Rep ; 11(1): 15833, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34349175

RESUMO

Metastatic disease remains the leading cause of death in cancer and understanding the mechanisms involved in tumor progression continues to be challenging. This work investigates the role of manganese in tumor progression in an in vivo model of tumor growth. Our data revealed that manganese accumulates within primary tumors and secondary organs as manganese-rich niches. Consequences of such phenomenon were investigated, and we verified that short-term changes in manganese alter cell surface molecules syndecan-1 and ß1-integrin, enhance collective cell migration and invasive behavior. Long-term increased levels of manganese do not affect cell growth and viability but enhance cell migration. We also observed that manganese is secreted from tumor cells in extracellular vesicles, rather than in soluble form. Finally, we describe exogenous glycosaminoglycans that counteract manganese effects on tumor cell behavior. In conclusion, our analyses describe manganese as a central element in tumor progression by accumulating in Mn-rich niches in vivo, as well as in vitro, affecting migration and extracellular vesicle secretion in vitro. Manganese accumulation in specific regions of the organism may not be a common ground for all cancers, nevertheless, it represents a new aspect of tumor progression that deserves special attention.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Pulmonar de Lewis/patologia , Movimento Celular , Manganês/metabolismo , Animais , Apoptose , Neoplasias da Mama/metabolismo , Carcinoma Pulmonar de Lewis/metabolismo , Proliferação de Células , Progressão da Doença , Feminino , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Invasividade Neoplásica , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Mol Recognit ; 34(10): e2922, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34132435

RESUMO

Using a rat model of peritonitis, we herein report the inflammatory effect induced by the lectin isolated from Vatairea guianensis (VGL) seeds in the context of interactions between VGL and both toll-like receptor 4 (TLR4) and tumor necrosis factor receptor 1 (TNFR1). Peritoneal macrophages were stimulated with VGL for dose-dependent gene expression and release of TNF-α. In vivo results showed that VGL (1 mg/kg; intraperitoneal) induced peritonitis in female Wistar rats. Leukocyte migration, macrophage activation, and protein leakage were measured 3 and 6 hours after induction. In vitro, peritoneal macrophages were stimulated with VGL for gene expression and TNF-α dosage (mean ± SEM (n = 6), analysis of variance, and Bonferroni's test (P < .05)). In silico, VGL structure was applied in molecular docking with representative glycans. It was found that (a) VGL increases vascular permeability and stimulates leukocyte migration, both rolling and adhesion; (b) lectin-induced neutrophil migration occurs via macrophage stimulation, both in vitro and in vivo; (c) lectin interacts with TLR4 and TNFR1; and (d) stimulates TNF-α gene expression (RT-PCR) and release from peritoneal macrophages. Thus, upon lectin-glycan binding on the cell surface, our results suggest that VGL induces an acute inflammatory response, in turn activating the release of peritoneal macrophages via TNF-α and TLR and/or TNFR receptor pathways.


Assuntos
Fabaceae/química , Glicoconjugados/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Glicoconjugados/química , Leucócitos/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Peritonite/induzido quimicamente , Peritonite/metabolismo , Peritonite/patologia , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Ratos Wistar , Receptores Tipo I de Fatores de Necrose Tumoral/química , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
5.
Int J Biol Macromol ; 124: 548-556, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30500509

RESUMO

The parotoid gland of bufonids is characterized as a specialized integument region, formed by different gland types. The secretion elaborated by the largest glandular alveoli has been related to animal chemical defense and is constituted by granular protein content, associated with a basophilic and alcianophilic material with features of glycoconjugates. This study aimed to identify and characterize the glycoconjugates in the secretion of the largest granular gland of the parotoid gland of Rinella icterica by histochemical and immunohistochemical techniques at light microscopy, biochemical methods, and nuclear magnetic resonance spectroscopy. Our results showed that the glycoconjugate content contains a mixture of chondroitin­6­sulfate (C6S) and chondroitin-non-sulfate (C0S). Thus, chondroitin sulfate probably plays an important role in gland physiology, probably protecting the protein content while inside the secretory portion.


Assuntos
Acetilgalactosamina/química , Bufonidae/metabolismo , Sulfatos de Condroitina/química , Ácido Glucurônico/química , Glicoconjugados/química , Glândula Parótida/química , Acetilgalactosamina/isolamento & purificação , Animais , Brasil , Bufonidae/anatomia & histologia , Sequência de Carboidratos , Sulfatos de Condroitina/isolamento & purificação , Ácido Glucurônico/isolamento & purificação , Glicoconjugados/isolamento & purificação , Masculino , Glândula Parótida/anatomia & histologia , Glândula Parótida/fisiologia
6.
Glycoconj J ; 34(3): 277-283, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27614617

RESUMO

Glycosaminoglycans with unique sulfation patterns have been identified in different species of ascidians (sea squirts), a group of marine invertebrates of the Phylum Chordata, sub-phylum Tunicata (or Urochordata). Oversulfated dermatan sulfate composed of [4-α-L-IdoA-(2-O-SO3)-1 â†’ 3-ß-D-GalNAc(4-OSO3)-1]n repeating disaccharide units is found in the extracellular matrix of several organs, where it seems to interact with collagen fibers. This dermatan sulfate co-localizes with a decorin-like protein, as indicated by immunohistochemical analysis. Low sulfated heparin/heparan sulfate-like glycans composed mainly of [4-α-L-IdoA-(2-OSO3)-1 â†’ 4-α-D-GlcN(SO3)-1 (6-O-SO3)-1]n and [4-α-L-IdoA-(2-O-SO3)-1 â†’ 4-α-D-GlcN(SO3)-1]n have also been described in ascidians. These heparin-like glycans occur in intracellular granules of oocyte assessory cells, named test cells, in circulating basophil-like cells in the hemolymph, and at the basement membrane of different ascidian organs. In this review, we present an overview of the structure, distribution, extracellular and intracellular localization of the sulfated glycosaminoglycans in different species and tissues of ascidians. Considering the phylogenetic position of the subphylum Tunicata in the phylum Chordata, a careful analysis of these data can reveal important information about how these glycans evolved from invertebrate to vertebrate animals.


Assuntos
Estruturas Animais/fisiologia , Dermatan Sulfato/química , Dissacarídeos/química , Filogenia , Urocordados/fisiologia , Estruturas Animais/anatomia & histologia , Estruturas Animais/química , Animais , Configuração de Carboidratos , Sequência de Carboidratos , Colágeno/química , Decorina/química , Dermatan Sulfato/isolamento & purificação , Dissacarídeos/isolamento & purificação , Matriz Extracelular/química , Matriz Extracelular/fisiologia , Hemolinfa/química , Hemolinfa/fisiologia , Urocordados/anatomia & histologia , Urocordados/química , Urocordados/classificação
7.
Biochim Biophys Acta ; 1840(8): 2599-608, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24747732

RESUMO

BACKGROUND: Heparanase is the only known mammalian glycosidase capable of cleaving heparan sulfate chains. The expression of this enzyme has been associated with tumor development because of its ability to degrade extracellular matrix and promote cell invasion. METHODS: We analyzed heparanase expression in lung cancer samples to understand lung tumor progression and malignancy. Of the samples from 37 patients, there were 14 adenocarcinomas, 13 squamous cell carcinomas, 5 large cell carcinomas, and 5 small cell carcinomas. Immunohistochemistry was performed to ascertain the expression and localization of heparanase. RESULTS: All of the tumor types expressed heparanase, which was predominantly localized within the cytoplasm and nucleus. Significant enzyme expression was also observed in cells within the tumor microenvironment, such as fibroblasts, epithelial cells, and inflammatory cells. Adenocarcinomas exhibited the strongest heparanase staining intensity and the most widespread heparanase distribution. Squamous cell carcinomas, large cell carcinomas, and small cell carcinomas had a similar subcellular distribution of heparanase to adenocarcinomas but the distribution was less widespread. Heparanase expression tended to correlate with tumor node metastasis (TNM) staging in non-small cell lung carcinoma. CONCLUSION: In this study, we showed that heparanase was localized to the cytoplasm and nucleus of tumor cells and to cells within the microenvironment in different types of lung cancer. This enzyme exhibited a differential distribution based on the type of lung tumor. General significance Elucidating the heparanase expression patterns in different types of lung cancer increased our understanding of the crucial role of heparanase in lung cancer biology. This article is part of a Special Issue entitled Matrix-mediated cell behaviour and properties.


Assuntos
Glucuronidase/metabolismo , Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/enzimologia , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Diferenciação Celular , Membrana Celular/enzimologia , Núcleo Celular/enzimologia , Núcleo Celular/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Linfócitos/enzimologia , Macrófagos/enzimologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Transporte Proteico , Coloração e Rotulagem , Microambiente Tumoral
8.
Surgery ; 155(2): 217-27, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24287143

RESUMO

AIM: We sought to investigate whether mammalian or ascidian Styela plicata heparin enemas could diminish inflammation in experimental diversion colitis. METHODS: Wistar-specific pathogen-free rats were submitted to a Hartmann's end colostomy and treated with enemas containing mammalian or Styela plicata heparin, or saline. Enemas were administered 3 times a week in the excluded colon segment from 4 to 8 weeks after operation. The effect of treatment was evaluated using video-endoscopic and histologic scores, measuring the cytokines interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF)-α, and transforming growth factor-ß production in organ cultures by enzyme-linked immunosorbent assay, quantifying T cells and macrophages, and investigating nuclear factor-kappa B (NF-κB) and external mitogen-activated protein kinase (pERK) activation. RESULTS: Treatment with either mammalian or Styela plicata heparins decreased colonoscopic and histologic scores (P < .02) and restored the densities of collagen fibers and the number of goblet cells (P < .03) in the diverted colon. Both heparin treatments decreased the accumulation of T cells and macrophages (P < .03), and the activation of NF-κB and pERK (P < .04) in the diverted colon. The high levels of cytokines IL-1ß, TNF-α, and IL-6 from the diversion colitis explants decreased (P < .05) to near normal values with heparin treatments. CONCLUSION: The improvement of experimental diversion colitis with heparin treatments indicates the anti-inflammatory effect of these compounds, even after topical administration. Further studies with the nonhemorrhagic heparin obtained from the invertebrate Styela plicata will be necessary to confirm its efficacy for the treatment of human diversion colitis and possibly other forms of colitis.


Assuntos
Anticoagulantes/administração & dosagem , Colite/tratamento farmacológico , Enema , Heparina/administração & dosagem , Urocordados , Animais , Colite/patologia , Colágeno/metabolismo , Colo/metabolismo , Colo/patologia , Colonoscopia , Modelos Animais de Doenças , Feminino , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar
9.
Säo Paulo; s.n; 1993. 92 p. ilus, tab.
Tese em Português | LILACS | ID: lil-204020
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