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1.
Biomolecules ; 11(8)2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34439775

RESUMO

Galectin-3 (gal-3) is a fibrosis marker and may play a role in fibrosis of the left atrium (LA). Left atrial wall fibrosis may influence the transition from paroxysmal to non-paroxysmal atrial fibrillation (AF). In this study, we assessed the correlation of gal-3 concentration with the main echocardio-graphic parameters evaluating dimensions, volume, compliance, and left atrial contractility during AF and after successful electrical cardioversion (DCCV). The study included 63 patients with left atrial enlargement who qualified for DCCV due to persistent AF. The procedure recovered sinus rhythm in 43 (68.3%) patients. The concentration of gal-3 was negatively correlated with the echocardiographic parameters of LA including dimensions (LA length pre, rho = -0.38; p = 0.003), volume (LAV pre, rho = -0.39; p = 0.003), compliance (LASr mean post, rho = -0.33) and contractility (pLASRct mean post, rho = -0.33; p = 0.038). Negative correlations of gal-3 concentration were also observed in relation to the volume and contractility of the left ventricle. The concentration of gal-3 significantly negatively correlates with the size, systolic function, and compliance of the LA wall in patients with persistent AF. Determining gal-3 concentration in patients with persistent AF may help in the assessment of remodeling of the LA wall.


Assuntos
Fibrilação Atrial/metabolismo , Remodelamento Atrial , Proteínas Sanguíneas/metabolismo , Fibrose Endomiocárdica/metabolismo , Galectinas/metabolismo , Átrios do Coração/metabolismo , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/terapia , Biomarcadores/metabolismo , Proteínas Sanguíneas/genética , Ecocardiografia , Cardioversão Elétrica/métodos , Fibrose Endomiocárdica/diagnóstico por imagem , Fibrose Endomiocárdica/fisiopatologia , Fibrose Endomiocárdica/terapia , Feminino , Galectinas/genética , Expressão Gênica , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Função Ventricular Esquerda
2.
Eur J Med Chem ; 223: 113664, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34225180

RESUMO

We have obtained the X-ray crystal structure of the galectin-8 N-terminal domain (galectin-8N) with a previously reported quinoline-galactoside ligand at a resolution of 1.6 Å. Based on this X-ray structure, a collection of galactosides derivatised at O3 with triazole, benzimidazole, benzothiazole, and benzoxazole moieties were designed and synthesised. This led to the discovery of a 3-O-(N-methylbenzimidazolylmethyl)-galactoside with a Kd of 1.8 µM for galectin-8N, the most potent selective synthetic galectin-8N ligand to date. Molecular dynamics simulations showed that benzimidazole-galactoside derivatives bind the non-conserved amino acid Gln47, accounting for the higher selectivity for galectin-8N. Galectin-8 is a carbohydrate-binding protein that plays a key role in pathological lymphangiogenesis, modulation of the immune system, and autophagy. Thus, the benzimidazole-derivatised galactosides represent promising compounds for studies of the pathological implications of galectin-8, as well as a starting point for the development of anti-tumour and anti-inflammatory therapeutics targeting galectin-8.


Assuntos
Benzimidazóis/química , Desenho de Fármacos , Galactosídeos/química , Galectinas/química , Benzimidazóis/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Galactosídeos/metabolismo , Galectinas/genética , Galectinas/metabolismo , Humanos , Cinética , Ligantes , Simulação de Dinâmica Molecular , Ligação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Relação Estrutura-Atividade , Termodinâmica
3.
Biomolecules ; 11(6)2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198494

RESUMO

It has been almost 25 years since the discovery of galectin-7. This member of the galectin family has attracted interest from many working in the cancer field given its highly restricted expression profile in epithelial cells and the fact that cancers of epithelial origin (carcinoma) are among the most frequent and deadly cancer subtypes. Initially described as a p53-induced gene and associated with apoptosis, galectin-7 is now recognized as having a protumorigenic role in many cancer types. Several studies have indeed shown that galectin-7 is associated with aggressive behavior of cancer cells and induces expression of MMP-9, a member of the matrix metalloproteinases (MMP) family known to confer invasive behavior to cancer cells. It is therefore not surprising that many studies have examined its relationships with p53 and MMP-9. However, the relationships between galectin-7 and p53 and MMP-9 are not always clear. This is largely because p53 is often mutated in cancer cells and such mutations drastically change its functions and, consequently, its association with galectin-7. In this review, we discuss the functional relationships between galectin-7, p53 and MMP-9 and reconcile some apparently contradictory observations. A better understanding of these relationships will help to develop a working hypothesis and model that will provide the basis for further research in the hope of establishing a new paradigm for tackling the role of galectin-7 in cancer.


Assuntos
Galectinas/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Galectinas/genética , Humanos , Metaloproteinase 9 da Matriz/genética , Invasividade Neoplásica , Neoplasias/genética , Neoplasias/patologia , Proteína Supressora de Tumor p53/genética
4.
Histochem Cell Biol ; 156(3): 253-272, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34152508

RESUMO

Wild-type lectins have distinct types of modular design. As a step to explain the physiological importance of their special status, hypothesis-driven protein engineering is used to generate variants. Concerning adhesion/growth-regulatory galectins, non-covalently associated homodimers are commonly encountered in vertebrates. The homodimeric galectin-7 (Gal-7) is a multifunctional context-dependent modulator. Since the possibility of conversion from the homodimer to hybrids with other galectin domains, i.e. from Gal-1 and Gal-3, has recently been discovered, we designed Gal-7-based constructs, i.e. stable (covalently linked) homo- and heterodimers. They were produced and purified by affinity chromatography, and the sugar-binding activity of each lectin unit proven by calorimetry. Inspection of profiles of binding of labeled galectins to an array-like platform with various cell types, i.e. sections of murine epididymis and jejunum, and impact on neuroblastoma cell proliferation revealed no major difference between natural and artificial (stable) homodimers. When analyzing heterodimers, acquisition of altered properties was seen. Remarkably, binding properties and activity as effector can depend on the order of arrangement of lectin domains (from N- to C-termini) and on the linker length. After dissociation of the homodimer, the Gal-7 domain can build new functionally active hybrids with other partners. This study provides a clear direction for research on defining the full range of Gal-7 functionality and offers the perspective of testing applications for engineered heterodimers.


Assuntos
Galectinas/metabolismo , Engenharia de Proteínas , Linhagem Celular Tumoral , Galectinas/análise , Galectinas/isolamento & purificação , Humanos , Espectrometria de Massas
5.
Front Immunol ; 12: 639260, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093526

RESUMO

The parasitic nematode Trichinella spiralis causes trichinellosis, a serious food-borne parasitic zoonosis worldwide. Infection with T. spiralis may also cause myocarditis. In the present study, we used mouse models to assess the impact of blockage of galectin-receptor interactions by α-lactose on cardiac immunopathology during acute T. spiralis experimental infection. Our data demonstrated that, after T. spiralis infection, blockage of galectin-receptor interactions resulted in cardiac dysfunction detected by transthoracic conventional echocardiography, and increased serum Gal-3 level, a biomarker of myocardial damage. In addition, there were increased eosinophil number in peripheral blood, and increased eosinophil infiltration in the heart and spleen tissues accompanied with increased mRNA levels of eosinophil granule proteins (including eosinophil cationic protein (ECP) and eosinophil peroxidase (EPO)) and IL-5 in these organs; increased cardiac fibrosis accompanied with increased Gal-3 and collagen 1 expressions in the hearts of mice with blockage of galectin-receptor interactions after T. spiralis infection. Correlation analysis showed that significant positive correlations existed between the mRNA levels of Gal-3 and ECP/EPO/eosinophil major basic protein/IL-5/CCL11/CCR3/α-SMA/collagen 1 in the hearts of both T. spiralis-infected mice and T. spiralis-infected mice with blockage of galectin-receptor interactions. Our data suggest that galectin-receptor interactions play a pivotal role during acute T. spiralis infection, and lack of galectin-receptor interactions upregulates Gal-3 which, in turn, leads to elevated heart eosinophil recruitment, exacerbated heart pathology and fibrosis, and heart functional damage.


Assuntos
Galectinas/metabolismo , Cardiopatias/metabolismo , Cardiopatias/patologia , Coração/parasitologia , Trichinella spiralis/parasitologia , Triquinelose/metabolismo , Triquinelose/patologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Eosinofilia/metabolismo , Eosinofilia/parasitologia , Eosinofilia/patologia , Eosinófilos/metabolismo , Eosinófilos/parasitologia , Eosinófilos/patologia , Feminino , Fibrose/metabolismo , Fibrose/parasitologia , Fibrose/patologia , Cardiopatias/parasitologia , Camundongos , RNA Mensageiro/metabolismo , Baço/metabolismo , Baço/parasitologia , Baço/patologia , Triquinelose/parasitologia , Regulação para Cima/fisiologia
6.
Biochim Biophys Acta Proteins Proteom ; 1869(10): 140684, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34146732

RESUMO

The galectin family is a representative soluble lectin group, which is responsible for the modulation of various cell functions. Although the carbohydrate-binding specificity of galectins has been well-studied, the relationship between protein structure and specificity remains to be elucidated. We previously reported the characteristics of a Xenopus laevis skin galectin, xgalectin-Va, which had diverged from galectin-1. The carbohydrate selectivity of xgalectin-Va was different from that of human galectin-1 and xgalectin-Ib (a Xenopus laevis galectin-1 homolog). In this study, we clarified the key residues for this selectivity by site-directed mutagenesis. Substitution of two amino acids of xgalectin-Va, Val56Gly/Lys76Arg, greatly enhanced the binding ability to N-acetyllactosamine and conferred significant T-cell growth inhibition activity, although the wild type had no activity. These two residues, Gly54 and Arg74 in galectin-1, would cooperatively contribute to the N-acetyllactosamine recognition. The loop region between the S4 and S5 ß-strands was involved in the binding to the TF-antigen disaccharide. The loop substitution successfully changed the carbohydrate selectivity of xgalectin-Va and xgalectin-Ib.


Assuntos
Substituição de Aminoácidos , Amino Açúcares/metabolismo , Galectinas/química , Galectinas/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Difusão Dinâmica da Luz , Galectinas/genética , Humanos , Células Jurkat , Modelos Moleculares , Mutagênese Sítio-Dirigida , Ligação Proteica , Conformação Proteica em Folha beta , Proteínas de Xenopus/química , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Xenopus laevis
7.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34067978

RESUMO

Galectin-3 (Gal-3) is a ß-galactoside-binding protein that influences various cell functions, including cell adhesion. We focused on the role of Gal-3 as an extracellular ligand mediating cell-matrix adhesion. We used human adipose tissue-derived stem cells and human umbilical vein endothelial cells that are promising for vascular tissue engineering. We found that these cells naturally contained Gal-3 on their surface and inside the cells. Moreover, they were able to associate with exogenous Gal-3 added to the culture medium. This association was reduced with a ß-galactoside LacdiNAc (GalNAcß1,4GlcNAc), a selective ligand of Gal-3, which binds to the carbohydrate recognition domain (CRD) in the Gal-3 molecule. This ligand was also able to detach Gal-3 newly associated with cells but not Gal-3 naturally present on cells. In addition, Gal-3 preadsorbed on plastic surfaces acted as an adhesion ligand for both cell types, and the cell adhesion was resistant to blocking with LacdiNAc. This result suggests that the adhesion was mediated by a binding site different from the CRD. The blocking of integrin adhesion receptors on cells with specific antibodies revealed that the cell adhesion to the preadsorbed Gal-3 was mediated, at least partially, by ß1 and αV integrins-namely α5ß1, αVß3, and αVß1 integrins.


Assuntos
Proteínas Sanguíneas/metabolismo , Adesão Celular , Junções Célula-Matriz/metabolismo , Galectinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Integrinas/metabolismo , Células-Tronco Mesenquimais/fisiologia , Sítios de Ligação , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Ligação Proteica
8.
Eur J Med Chem ; 222: 113561, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34146913

RESUMO

Lectins are a family of glycan-binding proteins, many of which have been established as key targets for therapeutic intervention. They play a central role in many physiological and cellular processes. With the advances in protein crystallography, NMR spectroscopy and computational power over the past couple of decades, the carbohydrate-receptor interactions are now well understood and characterized. Nevertheless, designing efficient carbohydrate inhibitors is a laborious endeavour. They are known to have weak affinities, unsuitable pharmacokinetic properties and highly cumbersome/complex synthetic routes. To circumvent these issues many non-carbohydrate strategies have been reported. Galectins are a sub-family of lectin proteins which have been recognized as crucial targets for a wide variety of diseases. Many candidates targeting galectins are currently in advanced stages of clinical trials. There have been a few reports of non-carbohydrate inhibitors targeting galectins which comprise of peptide-based inhibitors and a recent flourish of heterocyclic inhibitors. In this review, we have briefly highlighted the strategies like fragment-based drug-design and high-throughput screens utilized to identify non-carbohydrate based antagonists for proteins wherein the presence of a sugar was believed to be essential. Additionally, we have described the literature pertaining to non-carbohydrate inhibitors of galectins and how previous reports on rational substitution of a sugar motif could aid in design of heterocyclics that inhibit lectins/galectins. We have concluded with remarks on challenges, gap in our understanding and future perspectives concerned with rational design of non-carbohydrate molecules targeting lectins/galectins.


Assuntos
Galectinas/antagonistas & inibidores , Peptídeos/farmacologia , Relação Dose-Resposta a Droga , Galectinas/metabolismo , Estrutura Molecular , Peptídeos/química , Relação Estrutura-Atividade
9.
Commun Biol ; 4(1): 718, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112916

RESUMO

Recently, we involved the carbohydrate-binding protein Galectin-3 (Gal-3) as a druggable target for KRAS-mutant-addicted lung and pancreatic cancers. Here, using glioblastoma patient-derived stem cells (GSCs), we identify and characterize a subset of Gal-3high glioblastoma (GBM) tumors mainly within the mesenchymal subtype that are addicted to Gal-3-mediated macropinocytosis. Using both genetic and pharmacologic inhibition of Gal-3, we showed a significant decrease of GSC macropinocytosis activity, cell survival and invasion, in vitro and in vivo. Mechanistically, we demonstrate that Gal-3 binds to RAB10, a member of the RAS superfamily of small GTPases, and ß1 integrin, which are both required for macropinocytosis activity and cell survival. Finally, by defining a Gal-3/macropinocytosis molecular signature, we could predict sensitivity to this dependency pathway and provide proof-of-principle for innovative therapeutic strategies to exploit this Achilles' heel for a significant and unique subset of GBM patients.


Assuntos
Proteínas Sanguíneas/metabolismo , Neoplasias Encefálicas/metabolismo , Galectinas/metabolismo , Glioblastoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Proteínas Sanguíneas/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Feminino , Galectinas/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Células-Tronco Neoplásicas/patologia , Pinocitose , Mapas de Interação de Proteínas , Transcriptoma , Células Tumorais Cultivadas
10.
FASEB J ; 35(7): e21556, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34137463

RESUMO

Tim-3 is a negative immunoregulator in anti-tumor response, but its mechanism in chronic lymphocytic leukemia (CLL) is not yet clear. The aim of this study was to understand the role of Galectin-9/Tim-3 signaling pathway in the regulation of CD4+ T cell subsets in CLL patients. Flow cytometry results showed that the number of Treg cells obviously increased, and there was a significant Treg/Th17 imbalance in CLL patients. In addition, Tim-3 overexpressed on the surface of Th1 and Treg cells in CLL patients. The levels of Galectin-9 and IL-10 were significantly elevated in patients of CLL, especially in stages of Binet B, and C. However, IFN-γ decreased. Moreover, Galectin-9 in CLL patients was positively correlated with the number of Tim-3+ Treg cells and the level of IL-10. Interestingly, when the Tim-3/Galectin-9 pathway was blocked in vitro, the level of IL-10 in the culture supernatant of CD4+ T was significantly reduced, while the levels of IFN-γ and TNF-α were increased. After co-culture with activated Th1 cells, the apoptosis of CLL cells was significantly increased, and this effect was reversed after treatment with Tim-3+ Tregs. In summary, Galectin-9/Tim-3 are elevated in CLL and associated with disease progression. By the negative regulation of CD4+ T cells, activated Galectin-9/Tim-3 suppresses Th1 effector function and also promotes Treg to be involved in immune escape of CLL. This pathway might become the potential target of immunotherapy in CLL patients.


Assuntos
Galectinas/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Leucemia Linfocítica Crônica de Células B/imunologia , Ativação Linfocitária/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Idoso , Estudos de Casos e Controles , Feminino , Galectinas/genética , Receptor Celular 2 do Vírus da Hepatite A/genética , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Transdução de Sinais
11.
Tumour Biol ; 43(1): 77-96, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33998569

RESUMO

Cancer metastasis and therapy resistance are the foremost hurdles in oncology at the moment. This review aims to pinpoint the functional aspects of a unique multifaceted glycosylated molecule in both intracellular and extracellular compartments of a cell namely galectin-3 along with its metastatic potential in different types of cancer. All materials reviewed here were collected through the search engines PubMed, Scopus, and Google scholar. Among the 15 galectins identified, the chimeric gal-3 plays an indispensable role in the differentiation, transformation, and multi-step process of tumor metastasis. It has been implicated in the molecular mechanisms that allow the cancer cells to survive in the intravascular milieu and promote tumor cell extravasation, ultimately leading to metastasis. Gal-3 has also been found to have a pivotal role in immune surveillance and pro-angiogenesis and several studies have pointed out the importance of gal-3 in establishing a resistant phenotype, particularly through the epithelial-mesenchymal transition process. Additionally, some recent findings suggest the use of gal-3 inhibitors in overcoming therapeutic resistance. All these reports suggest that the deregulation of these specific lectins at the cellular level could inhibit cancer progression and metastasis. A more systematic study of glycosylation in clinical samples along with the development of selective gal-3 antagonists inhibiting the activity of these molecules at the cellular level offers an innovative strategy for primary cancer prevention.


Assuntos
Proteínas Sanguíneas/metabolismo , Carcinogênese/patologia , Epigênese Genética/genética , Galectinas/metabolismo , Neoplasias/patologia , Apoptose/fisiologia , Proteínas Sanguíneas/genética , Carcinogênese/genética , Transição Epitelial-Mesenquimal/genética , Galectinas/genética , Glicosilação , Humanos , Metástase Neoplásica/patologia , Neoplasias/genética
12.
Nutr Metab Cardiovasc Dis ; 31(6): 1791-1797, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34023181

RESUMO

BACKGROUND AND AIMS: Gestational diabetes mellitus (GDM), hyperglycemia diagnosed during pregnancy, is one of the most common medical complications of pregnancy, treated primarily by diet and pharmacotherapy, if indicated. It is well-established that GDM increases the risk of adverse pregnancy outcomes and long-term complications in mothers and infants. Galectin-3 (Gal-3) is important in processes of cell growth, differentiation, inflammation, and fibrosis. We evaluated Gal-3 expression in pregnancies complicated by GDM as a parameter that might explain how GDM influences early onset of future complications. METHODS AND RESULTS: Forty-four women with GDM and 40 with normal pregnancy (NP) were recruited during delivery admission. Blood samples were obtained from parturients and umbilical cords blood, as well as placental tissue for analysis. Gal-3 mRNA expression was increased in maternal blood samples and placental tissue of women with GDM compared to NP. In GDM, Gal-3 mRNA was decreased in cord blood compared to maternal blood and placental tissue. Gal-3 GDM placental protein expression was increased compared to NP. Immunostaining revealed that Gal-3 is upregulated in GDM placental extravillous trophoblast. ELISA of Gal-3 maternal serum levels between GDM and NP were similar. CONCLUSION: Gal-3 is strongly expressed at molecular levels (mRNA and protein expression) in GDM maternal blood and placental tissue, and decreased in cord blood. These findings highlight the role of the placenta in protecting the fetus from potential Gal-3 damage. Gal-3 expression at mRNA and protein levels might be influenced by diabetes, even if blood glucose is balanced by medication or diet.


Assuntos
Proteínas Sanguíneas/metabolismo , Diabetes Gestacional/metabolismo , Galectinas/metabolismo , Placenta/metabolismo , Adulto , Biomarcadores/metabolismo , Proteínas Sanguíneas/genética , Estudos de Casos e Controles , Diabetes Gestacional/sangue , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/genética , Feminino , Sangue Fetal/metabolismo , Galectinas/sangue , Galectinas/genética , Humanos , Troca Materno-Fetal , Gravidez , Regulação para Cima
13.
Mol Immunol ; 135: 342-350, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33984607

RESUMO

Tim-3, which is expressed on a variety of innate immune cells including NK cells, plays a key role in many autoimmune diseases. However, the immunomodulatory actions of Tim-3 on NK cells in primary biliary cholangitis (PBC) remain uncertain. Using a murine model of PBC we evaluated the expression of Tim-3 and its ligand Gal-9 in peripheral blood, liver, and spleen. Additionally, we studied Tim-3 regulation of chemokine receptors (CXCR1 and CXCR3) in vitro. Flow cytometric analysis indicated large numbers of infiltrating NK cells in the liver which exhibited high expression of Tim-3 and CXCR3. Moreover, we found overexpression of CXCR1 in liver tissue and liver-derived NK cells in PBC mice. We also observed lower levels of soluble Tim-3 in the serum of PBC mice. In vitro experiments with liver-derived NK cells from PBC mice indicated that CXCR3 was up-regulated by treatment with recombinant mouse TIM-3 Fc (rmTim-3 Fc) to activate the Tim-3 pathway. Furthermore, stimulating normal mouse spleen NK cells with poly I:C resulted in elevated expression of CXCR1 and interferon-γ release. Nonetheless, adding rmTim-3 Fc or rmGal-9 significantly down-regulated CXCR1 expression and IFN-γ release in NK cells activated by poly I:C, proposing a means to exploit the Tim-3 pathway to reverse responses in NK cells. In conclusion, our data demonstrate that dysregulation of Tim-3/Gal-9 is involved in modulating the local immune microenvironment in PBC mice. Our findings highlight the potential of Tim-3 pathway to modulate chemokine responses in NK cells during autoimmunity.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Células Matadoras Naturais/imunologia , Cirrose Hepática Biliar/patologia , Receptores CXCR3/biossíntese , Receptores de Interleucina-8A/biossíntese , Animais , Autoimunidade/imunologia , Células Cultivadas , Microambiente Celular/imunologia , Modelos Animais de Doenças , Feminino , Galectinas/metabolismo , Regulação da Expressão Gênica/genética , Receptor Celular 2 do Vírus da Hepatite A/sangue , Interferon gama/biossíntese , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Baço/metabolismo
14.
Eur J Med Chem ; 220: 113500, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33962190

RESUMO

Galectin-3 plays a crucial role in cancerogenesis; its targeting is a prospective pathway in cancer diagnostics and therapy. Multivalent presentation of glycans was shown to strongly increase the affinity of glycoconjugates to galectin-3. Further strengthening of interaction with galectin-3 may be accomplished using artificial glycomimetics with apt aryl substitutions. We established a new, as yet undescribed chemoenzymatic method to produce selective C-3-substituted N,N'-diacetyllactosamine glycomimetics and coupled them to human serum albumin. From a library of enzymes, only ß-N-acetylhexosaminidase from Talaromyces flavus was able to efficiently synthesize the C-3-propargylated disaccharide. Various aryl residues were attached to the functionalized N,N'-diacetyllactosamine via click chemistry to assess the impact of the aromatic substitution. In ELISA-type assays with galectin-3, free glycomimetics exhibited up to 43-fold stronger inhibitory potency to Gal-3 than the lactose standard. Coupling to human serum albumin afforded multivalent neo-glycoproteins with up to 4209-fold increased inhibitory potency per glycan compared to the monovalent lactose standard. Surface plasmon resonance brought further information on the kinetics of galectin-3 inhibition. The potential of prepared neo-glycoproteins to target galectin-3 was demonstrated on colorectal adenocarcinoma DLD-1 cells. We investigated the uptake of neo-glycoproteins into cells and observed limited non-specific transport into the cytoplasm. Therefore, neo-glycoproteins primarily act as efficient scavengers of exogenous galectin-3 of cancer cells, inhibiting its interaction with the cell surface, and protecting T-lymphocytes against galectin-3-induced apoptosis. The present neo-glycoproteins combine the advantage of a straightforward synthesis, selectivity, non-toxicity, and high efficiency for targeting exogenous galectin-3, with possible application in the immunomodulatory treatment of galectin-3-overexpressing cancers.


Assuntos
Materiais Biomiméticos/farmacologia , Proteínas Sanguíneas/antagonistas & inibidores , Galectinas/antagonistas & inibidores , Glicoproteínas/metabolismo , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Relação Dose-Resposta a Droga , Galectinas/genética , Galectinas/metabolismo , Glicoproteínas/química , Humanos , Cinética , Estrutura Molecular , Relação Estrutura-Atividade
15.
Eur J Pharmacol ; 902: 174119, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33930385

RESUMO

MUC1 seems to be promising target in cancer cells due to its abundant and specifically altered expression as well as differential distribution pattern relative to normal tissues. Rosmarinic acid (RA) is a natural, polyphenolic compound with pharmacological activities, including anti-cancer. Herein, we aim to explore the effect of combined action of anti-MUC1 and RA on selected cancer-related factors in AGS gastric cancer cells. Cancer cells were treated with 100, 200 µM rosmarinic acid, 5 µg/ml anti-MUC1 and acid together with antibody. Western blotting, ELISA and RT-PCR were used to assess the expression of MUC1, selected sugar antigens, enzymes participating in protein glycosylation, Gal-3, p53, pro- and anti-apoptotic factors, and caspases-3,-8,-9 in cancer cells. MUC1 mRNA was significantly suppressed by combined action of anti-MUC1 and RA. Such treatment markedly inhibited expression of cancer-related Tn, T, sialyl Tn, sialyl T, and fucosylated sugar antigens as well as mRNA expression of enzymes participating in their formation: ppGalNAcT2, C1GalT1, ST6GalNAcT2, ST3GalT1 and FUT4. C1GalT1 was suppressed also on protein level. Gal-3, factor likely participating in metastasis, was significantly suppressed on mRNA level by RA administrated with anti-MUC1. Pro-apoptotic Bax protein and Bad mRNA were significantly induced, and anti-apoptotic Bcl-2 mRNA expression was inhibited by such treatment. Combined action of mAb and RA markedly increased caspase-9 mRNA expression. Results of the study indicate that combined action of anti-MUC1 and RA is more effective than monotherapy in relation to examined cancer related factors. Such treatment can be considered as new, promising strategy in gastric cancer therapy.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Antineoplásicos/farmacologia , Cinamatos/farmacologia , Depsídeos/farmacologia , Mucina-1/imunologia , Mucina-1/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Galectinas/genética , Galectinas/metabolismo , Glicosilação/efeitos dos fármacos , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Humanos , Mucina-1/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína de Morte Celular Associada a bcl/genética , Proteína de Morte Celular Associada a bcl/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
16.
Biomolecules ; 11(4)2021 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-33919637

RESUMO

Galectins bind various pathogens through recognition of distinct carbohydrate structures. In this work, we examined the binding of four human galectins to the Gram-negative bacteria Klebsiella pneumoniae (Kpn) and non-typeable Haemophilus influenzae (NTHi), which display different surface glycans. In particular, Kpn cells are covered by a polysaccharide capsule and display an O-chain-containing lipopolysaccharide (LPS), whereas NTHi is not capsulated and its LPS, termed lipooligosacccharide (LOS), does not contain O-chain. Binding assays to microarray-printed bacteria revealed that galectins-3, -4, and -8, but not galectin-1, bind to Kpn and NTHi cells, and confocal microscopy attested binding to bacterial cells in suspension. The three galectins bound to array-printed Kpn LPS. Moreover, analysis of galectin binding to mutant Kpn cells evidenced that the O-chain is the docking point for galectins on wild type Kpn. Galectins-3, -4, and -8 also bound the NTHi LOS. Microarray-assisted comparison of the binding to full-length and truncated LOSs, as well as to wild type and mutant cells, supported LOS involvement in galectin binding to NTHi. However, deletion of the entire LOS oligosaccharide chain actually increased binding to NTHi cells, indicating the availability of other ligands on the bacterial surface, as similarly inferred for Kpn cells devoid of both O-chain and capsule. Altogether, the results illustrate galectins' versatility for recognizing different bacterial structures, and point out the occurrence of so far overlooked galectin ligands on bacterial surfaces.


Assuntos
Galectinas/metabolismo , Haemophilus influenzae/metabolismo , Klebsiella pneumoniae/metabolismo , Lipopolissacarídeos/metabolismo , Sítios de Ligação , Galectinas/química , Humanos , Lipopolissacarídeos/química , Ligação Proteica
17.
Cytokine Growth Factor Rev ; 60: 89-106, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33863623

RESUMO

Receptor tyrosine kinases (RTKs) constitute a large group of cell surface proteins that mediate communication of cells with extracellular environment. RTKs recognize external signals and transfer information to the cell interior, modulating key cellular activities, like metabolism, proliferation, motility, or death. To ensure balanced stream of signals the activity of RTKs is tightly regulated by numerous mechanisms, including receptor expression and degradation, ligand specificity and availability, engagement of co-receptors, cellular trafficking of the receptors or their post-translational modifications. One of the most widespread post-translational modifications of RTKs is glycosylation of their extracellular domains. The sugar chains attached to RTKs form a new layer of information, so called glyco-code that is read by galectins, carbohydrate binding proteins. Galectins are family of fifteen lectins implicated in immune response, inflammation, cell division, motility and death. The versatility of cellular activities attributed to galectins is a result of their high abundance and diversity of their cellular targets. A various sugar specificity of galectins and the differential ability of galectin family members to form oligomers affect the spatial distribution and the function of their cellular targets. Importantly, galectins and RTKs are tightly linked to the development, progression and metastasis of various cancers. A growing number of studies points on the close cooperation between RTKs and galectins in eliciting specific cellular responses. This review focuses on the identified complexes between galectins and RTK members and discusses their relevance for the cell physiology both in healthy tissues and in cancer.


Assuntos
Transdução de Sinais , Galectinas/metabolismo , Humanos , Ligantes , Receptores Proteína Tirosina Quinases , Tirosina
18.
Int J Biol Macromol ; 181: 793-800, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33857510

RESUMO

Here, we compare the content and composition of polysaccharides derived from the mycelium (40.4 kDa intracellular polysaccharide, IPS) and culture (27.2 kDa extracellular polysaccharide, EPS) of Penicillium oxalicum. Their chemical structures investigated by IR, NMR, enzymolysis and methylation analysis indicate that both IPS and EPS are galactomannans composed of α-1,2- mannopyranose (Manp) and α-1,6-Manp in a backbone ratio of ~3:1, respectively, both decorated with ß-l,5-galactofuranose (Galf) side chains. A few ß-l,6-Galf residues were also detected in the IPS fraction. EPS and IPS have different molecular weights (Mw) and degrees of branching. IPS obtained by alkaline extraction of P. oxalicum have been reported to be galactofuranans, a composition different from our IPS. Up to now, there have been no reports on the fine structure of EPS. Our results of galectin-mediated hemagglutination demonstrate that IPS exhibits greater inhibitory effects on five galectins compared with EPS. In addition, we find that Galf, a five-membered ring form of galactose, can also inhibit galectins. IPS may provide a new source of galectin inhibitors. These results increase our understanding of structure-activity relationships of polysaccharides as galectin inhibitors.


Assuntos
Espaço Extracelular/química , Polissacarídeos Fúngicos/farmacologia , Galectinas/antagonistas & inibidores , Espaço Intracelular/química , Penicillium/química , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Ensaios Enzimáticos , Galectinas/metabolismo , Hemaglutinação/efeitos dos fármacos , Hidrólise , Metilação , Peso Molecular , Espectroscopia de Prótons por Ressonância Magnética , Ovinos , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Yakugaku Zasshi ; 141(4): 481-488, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-33790114

RESUMO

Two novel ß-trefoil lectins, MytiLec-1 and SeviL were found from mussels in the coast of Yokohama and Nagasaki. MytiLec-1 was purified from gill and mantle of Mytilus galloprovincialis. It was consisted of 149 amino acid residues and there was no similarity with any other proteins when it was discovered. We advocate for this "Mytilectin" as a new protein family because of their novelty of its primary structure and homologues were also found in other mussels. Glycan array analysis revealed that MytiLec-1 specifically bound to the Gb3 and Gb4 glycan which contained the α-galactoside. MytiLec-1 caused the apoptosis against the Burkitt's lymphoma cells through the interaction of Gb3 express in their cell surface. On the other hand, SeviL obtained from gill and mantle of Mytilisepta virgata showed the specific binding against GM1b, asialo GM1 and SSEA-4 which are known as glycosphingolipid glycan including the ß-galactoside. In addition, SeviL was identified as R type lectin by confirmation of QXW motif within its primary structure. Messenger RNA of SeviL like R type lectins was also found among the musssels including Mytilus galloprovincialis. SeviL also showed the apoptosis against asialo GM1 expressing cells. To apply the anticancer lectin as a novel molecular target drug, primary structure of MytiLec-1 was analyzed to enhance the stabilization of confirmation by computational design technique. It was succeeded to produce a monomeric artificial ß-trefoil lectin, Mitsuba-1 without losing the Gb3 binding ability. Comparison of biological function between Mitsuba-1 and MytiLec-1 is also described in this study.


Assuntos
Dissacarídeos/farmacologia , Galectinas/farmacologia , Lectinas/farmacologia , Mytilidae/química , Trissacarídeos/farmacologia , Animais , Antineoplásicos , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/patologia , Dissacarídeos/química , Dissacarídeos/isolamento & purificação , Dissacarídeos/metabolismo , Desenho de Fármacos , Galectinas/química , Galectinas/isolamento & purificação , Galectinas/metabolismo , Lectinas/química , Lectinas/isolamento & purificação , Lectinas/metabolismo , Conformação Molecular , Terapia de Alvo Molecular , Polissacarídeos/metabolismo , Sequências de Repetição em Tandem , Trissacarídeos/química , Trissacarídeos/isolamento & purificação , Trissacarídeos/metabolismo
20.
Biomolecules ; 11(3)2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804076

RESUMO

Galectin-9 (Gal-9) is a ß-galactoside-binding lectin capable of promoting or suppressing the progression of infectious diseases. This protein is susceptible to cleavage of its linker-peptides by several proteases, and the resulting cleaved forms, N-terminal carbohydrate recognition domain (CRD) and C-terminal CRD, bind to various glycans. It has been suggested that full-length (FL)-Gal-9 and the truncated (Tr)-Gal-9s could exert different functions from one another via their different glycan-binding activities. We propose that FL-Gal-9 regulates the pathogenesis of infectious diseases, including human immunodeficiency virus (HIV) infection, HIV co-infected with opportunistic infection (HIV/OI), dengue, malaria, leptospirosis, and tuberculosis (TB). We also suggest that the blood levels of FL-Gal-9 reflect the severity of dengue, malaria, and HIV/OI, and those of Tr-Gal-9 markedly reflect the severity of HIV/OI. Recently, matrix metallopeptidase-9 (MMP-9) was suggested to be an indicator of respiratory failure from coronavirus disease 2019 (COVID-19) as well as useful for differentiating pulmonary from extrapulmonary TB. The protease cleavage of FL-Gal-9 may lead to uncontrolled hyper-immune activation, including a cytokine storm. In summary, Gal-9 has potential to reflect the disease severity for the acute and chronic infectious diseases.


Assuntos
Doenças Transmissíveis/sangue , Galectinas/sangue , Doença Aguda , Sequência de Aminoácidos , COVID-19/sangue , COVID-19/fisiopatologia , Doença Crônica , Doenças Transmissíveis/imunologia , Doenças Transmissíveis/fisiopatologia , Dengue/sangue , Dengue/fisiopatologia , Galectinas/genética , Galectinas/metabolismo , Infecções por HIV/sangue , Infecções por HIV/fisiopatologia , Humanos , Fatores Imunológicos/metabolismo , Leptospirose/sangue , Leptospirose/fisiopatologia , Malária/sangue , Malária/fisiopatologia , Tuberculose/sangue , Tuberculose/fisiopatologia
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