Galectin-3 disruption impaired tumoral angiogenesis by reducing VEGF secretion from TGFβ1-induced macrophages.

PubMed

Machado, Camila Maria Longo; Andrade, Luciana Nogueira Sousa; Teixeira, Verônica Rodrigues; Costa, Fabrício Falconi; Melo, Camila Morais; dos Santos, Sofia Nascimento; Nonogaki, Suely; Liu, Fu-Tong; Bernardes, Emerson Soares; Camargo, Anamaria Aranha; Chammas, Roger

2014-04-01

In order to study the role of galectin-3 in tumor angiogenesis associated with tumor-associated macrophages (TAM) and tumor parenchyma, the galectin-3 expression was reconstituted in Tm1 melanoma cell line that lacks this protein. Galectin-3-expressing cells (Tm1G3) and mock-vector transfected cells (Tm1N3) were injected into wild-type (WT) and galectin-3 knockout (KO) C57Bl/6 mice. Tumors originated from Tm1G3 were larger in tumor volume with enlarged functional vessels, decreased necrotic areas, and increased vascular endothelial growth factor (VEGF) protein levels. Galectin-3-nonexpressing-cells injected into WT and KO showed increased levels of transforming growth factor beta 1 (TGFβ1) and, in WT animals this feature was also accompanied by increased VEGFR2 expression and its phosphorylation. In KO animals, tumors derived from galectin-3-expressing cells were infiltrated by CD68(+)-cells, whereas in tumors derived from galectin-3-nonexpressing-cells, CD68(+) cells failed to infiltrate tumors and accumulated in the periphery of the tumor mass. In vitro studies showed that Tm1G3 secreted more VEGF than Tm1N3 cells. In the latter case, TGFβ1 induced VEGF production. Basal secretion of VEGF was higher in WT-bone marrow-derived macrophages (BMDM) than in KO-BMDM. TGFβ1 induced secretion of VEGF only in WT-BMDM. Tm1G3-induced tumors had the Arginase I mRNA increased, which upregulated alternative macrophage (M2)/TAM induction. M2 stimuli, such as interleukin-4 (IL4) and TGFβ1, increased Arginase I protein levels and galectin-3 expression in WT- BMDM, but not in cells from KO mice. Hence, we report that galectin-3 disruption in tumor stroma and parenchyma decreases angiogenesis through interfering with the responses of macrophages to the interdependent VEGF and TGFβ1 signaling pathways. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Galectin-1 and Galectin-3 induce mitochondrial apoptotic pathway in Jurkat cells

NASA Astrophysics Data System (ADS)

Vasil'eva, O. A.; Isaeva, A. V.; Prokhorenko, T. S.; Zima, A. P.; Novitsky, V. V.

2016-08-01

Cellular malignant transformation is often accompanied by increased gene expression of low-molecular proteins of lectins family-galectins. But it is unknown how galectins promote tumor growth and malignization. Galectins-1 and galectin-3 are thought to be possible immunoregulators exerting their effects by regulating the balance of CD4+ lymphocytes. In addition it is known that tumor cells overexpressing galectins are capable of escaping immunological control, causing apoptosis of lymphocytes. The aim of the study is to investigate the role of galectin-1 and galectin-3 in the implementation of mitochondrial apoptotic pathway in Jurkat cells. Methods: Jurkat cells were used as a model for the study of T-lymphocytes. Jurkat cells were activated with antibodies to CD3 and CD28 and cultured with recombinant galectin-1 and -3. Apoptosis of Jurkat cells and depolarization of the mitochondrial membrane were assessed by flow cytometry. It was found that galectin-1 and galectin-3 have a dose-dependent pro-apoptotic effect on Jurkat cells in vitro and enlarge the number of cells with decreased mitochondrial membrane potential compared with intact cells.

Structural myocardial alterations in diabetes and hypertension: the role of galectin-3.

PubMed

Seferovic, Jelena P; Lalic, Nebojsa M; Floridi, Federico; Tesic, Milorad; Seferovic, Petar M; Giga, Vojislav; Lalic, Katarina; Jotic, Aleksandra; Jovicic, Snezana; Colak, Emina; Salerno, Gerardo; Cardelli, Patrizia; Di Somma, Salvatore

2014-10-01

Galectin-3 is a protein widely distributed in the heart, brain and blood vessels, and has a regulatory role in inflammation, immunology and cancer. Many studies demonstrated that the increased level of galectin-3 is associated with progressive fibrosis and stiffening of the myocardium. The aim of this study was to investigate the role of galectin-3 in patients with type 2 diabetes (T2D) and/or arterial hypertension (HT). Study population included 189 patients, with no coronary artery disease, divided into three groups: group 1 (T2D), group 2 (T2D+HT), and group 3 (HT). All subjects underwent routine laboratory tests, as well as specific biomarkers assessment [galectin-3, glycosylated hemoglobin (HbA1c), N- terminal fragment B-type natriuretic peptide (NT-proBNP)]. Cardiological evaluation included physical examination, transthoracic tissue Doppler echocardiography and stress echocardiography. The results of this study demonstrated significantly increased levels of galectin-3, blood glucose, and HbA1c in group 2. Also, echocardiographicaly, left ventricular (LV) diameters and IVS thickness were increased in this group of patients. Furthermore, in the same cohort a positive correlation between galectin-3 and NT-pro BNP, and galectin-3 and LV mass were demonstrated. In addition, a negative correlation between galectin-3 and LV end-diastolic diameter was revealed. This study revealed that levels of galectin-3 were higher in patients with both T2D and HT, and correlated with LV mass, indicating the potential role of this biomarker for early detection of myocardial structural and functional alterations.

G3-C12 Peptide Reverses Galectin-3 from Foe to Friend for Active Targeting Cancer Treatment.

PubMed

Sun, Wei; Li, Lian; Yang, Qingqing; Shan, Wei; Zhang, Zhirong; Huang, Yuan

2015-11-02

Galectin-3 is overexpressed by numerous carcinomas and is a potential target for active tumor treatments. On the other hand, galectin-3 also plays a key role in cancer progression and prevents cells from undergoing apoptosis, thereby offsetting the benefits of active targeting drugs. However, the relative contribution of the protective antiapoptotic effects of galectin-3 and the proapoptotic effects of galectin-3-targeted therapies has remained yet unrevealed. Here, we show that a galectin-3-binding peptide G3-C12 could reverse galectin-3 from foe to friend for active targeting delivery system. Results showed G3-C12 modified N-(2-hydroxypropyl)methacrylamide copolymer doxorubicin conjugates (G3-C12-HPMA-Dox) could internalize into galectin-3 overexpressed PC-3 cells via a highly specific ligand-receptor pathway (2.2 times higher cellular internalization than HPMA-Dox). The internalized Dox stimulated the translocation of galectin-3 to the mitochondria to prevent from apoptosis. In turn, this caused G3-C12-HPMA-Dox to concentrate into the mitochondria after binding to galectin-3 intracellularly. Initially, mitochondrial galectin-3 weakened Dox-induced mitochondrial damage; however, as time progressed, G3-C12 active-mediation allowed increasing amounts of Dox to be delivered to the mitochondria, which eventually induced higher level of apoptosis than nontargeted copolymers. In addition, G3-C12 downregulates galectin-3 expression, 0.43 times lower than control cells, which could possibly be responsible for the suppressed cell migration. Thus, G3-C12 peptide exerts sequential targeting to both cell membrane and mitochondria via regulating galectin-3, and eventually reverses and overcomes the protective effects of galectin-3; therefore, it could be a promising agent for the treatment of galectin-3-overexpressing cancers.

Elucidation of Hydrogen Bonding Patterns in Ligand-Free, Lactose- and Glycerol-Bound Galectin-3C by Neutron Crystallography to Guide Drug Design.

PubMed

Manzoni, Francesco; Wallerstein, Johan; Schrader, Tobias E; Ostermann, Andreas; Coates, Leighton; Akke, Mikael; Blakeley, Matthew P; Oksanen, Esko; Logan, Derek T

2018-05-24

The medically important drug target galectin-3 binds galactose-containing moieties on glycoproteins through an intricate pattern of hydrogen bonds to a largely polar surface-exposed binding site. All successful inhibitors of galectin-3 to date have been based on mono- or disaccharide cores closely resembling natural ligands. A detailed understanding of the H-bonding networks in these natural ligands will provide an improved foundation for the design of novel inhibitors. Neutron crystallography is an ideal technique to reveal the geometry of hydrogen bonds because the positions of hydrogen atoms are directly detected rather than being inferred from the positions of heavier atoms as in X-ray crystallography. We present three neutron crystal structures of the C-terminal carbohydrate recognition domain of galectin-3: the ligand-free form and the complexes with the natural substrate lactose and with glycerol, which mimics important interactions made by lactose. The neutron crystal structures reveal unambiguously the exquisite fine-tuning of the hydrogen bonding pattern in the binding site to the natural disaccharide ligand. The ligand-free structure shows that most of these hydrogen bonds are preserved even when the polar groups of the ligand are replaced by water molecules. The protonation states of all histidine residues in the protein are also revealed and correlate well with NMR observations. The structures give a solid starting point for molecular dynamics simulations and computational estimates of ligand binding affinity that will inform future drug design.

Galectin-3 levels relate in children to total body fat, abdominal fat, body fat distribution, and cardiac size.

PubMed

Dencker, Magnus; Arvidsson, Daniel; Karlsson, Magnus K; Wollmer, Per; Andersen, Lars B; Thorsson, Ola

2018-03-01

Galectin-3 has recently been proposed as a novel biomarker for cardiovascular disease in adults. The purpose of this investigation was to assess relationships between galectin-3 levels and total body fat, abdominal fat, body fat distribution, aerobic fitness, blood pressure, left ventricular mass, left atrial size, and increase in body fat over a 2-year period in a population-based sample of children. Our study included 170 children aged 8-11 years. Total fat mass and abdominal fat were measured by dual-energy x-ray absorptiometry (DXA). Body fat distribution was expressed as abdominal fat/total fat mass. Maximal oxygen uptake was assessed by indirect calorimetry during a maximal exercise test and scaled to body mass. Systolic and diastolic blood pressure and pulse pressure were measured. Left atrial size, left ventricular mass, and relative wall thickness were measured by echocardiography. Frozen serum samples were analyzed for galectin-3 by the Proximity Extension Assay technique. A follow-up DXA scan was performed in 152 children 2 years after the baseline exam. Partial correlations, with adjustment for sex and age, between galectin-3 versus body fat measurements indicated weak to moderate relationships. Moreover, left atrial size, left ventricular mass, and relative wall thickness and pulse pressure were also correlated with galectin-3. Neither systolic blood pressure nor maximal oxygen uptake was correlated with galectin-3. There was also a correlation between galectin-3 and increase in total body fat over 2 years, while no such correlations were found for the other fat measurements. More body fat and abdominal fat, more abdominal body fat distribution, more left ventricular mass, and increased left atrial size were all associated with higher levels of galectin-3. Increase in total body fat over 2 years was also associated with higher levels of galectin-3. What is Known: • Galectin-3 has been linked to obesity and been proposed to be a novel biomarker for cardiovascular disease in adults. • Information on this subject in children is very scarce. What is New: • The present study demonstrates a relationship between galectin-3 levels and total body fat, abdominal fat, body fat distribution, cardiac size and geometry, and increase in total body fat over 2 years in young children.

Galectin-3 Shapes Antitumor Immune Responses by Suppressing CD8+ T Cells via LAG-3 and Inhibiting Expansion of Plasmacytoid Dendritic Cells.

PubMed

Kouo, Theodore; Huang, Lanqing; Pucsek, Alexandra B; Cao, Minwei; Solt, Sara; Armstrong, Todd; Jaffee, Elizabeth

2015-04-01

Galectin-3 is a 31-kDa lectin that modulates T-cell responses through several mechanisms, including apoptosis, T-cell receptor (TCR) cross-linking, and TCR downregulation. We found that patients with pancreatic ductal adenocarcinoma (PDA) who responded to a granulocyte-macrophage colony-stimulating factor-secreting allogeneic PDA vaccine developed neutralizing antibodies to galectin-3 after immunization. We show that galectin-3 binds activated antigen-committed CD8(+) T cells only in the tumor microenvironment. Galectin-3-deficient mice exhibit improved CD8(+) T-cell effector function and increased expression of several inflammatory genes. Galectin-3 binds to LAG-3, and LAG-3 expression is necessary for galectin-3-mediated suppression of CD8(+) T cells in vitro. Lastly, galectin-3-deficient mice have elevated levels of circulating plasmacytoid dendritic cells, which are superior to conventional dendritic cells in activating CD8(+) T cells. Thus, inhibiting galectin-3 in conjunction with CD8(+) T-cell-directed immunotherapies should enhance the tumor-specific immune response. ©2015 American Association for Cancer Research.

Galectin-3: A novel substrate for c-Abl kinase.

PubMed

Balan, Vitaly; Nangia-Makker, Pratima; Jung, Young Suk; Wang, Yi; Raz, Avraham

2010-10-01

Galectin-3, a beta-galactoside-binding lectin, is found in cellular and extracellular location of the cell and has pleiotropic biological functions such as cell growth, cell adhesion and cell-cell interaction. It may exhibit anti- or pro-apoptotic activity depending on its localization and post-translational modifications. Two important post-translational modifications of galectin-3 have been reported: its cleavage and phosphorylation. Cleavage of galectin-3 was reported to be involved with angiogenic potential and apoptotic resistance. Phosphorylation of galectin-3 regulates its sugar-binding ability. In this report we have identified novel tyrosine phosphorylation sites in galectin-3 as well as the kinase responsible for its phosphorylation. Our results demonstrate that tyrosines at positions 79, 107 and 118 can be phosphorylated in vitro and in vivo by c-Abl kinase. Tyrosine 107 is the main target of c-Abl. Expression of galectin-3 Y107F mutant in galectin-3 null SK-Br-3 cells leads to morphological changes and increased motility compared to wild type galectin-3. Further investigation is needed to better understand the functional significance of the novel tyrosine phosphorylated sites of galectin-3. Copyright © 2010 Elsevier B.V. All rights reserved.

Galectin-3 released in response to traumatic brain injury acts as an alarmin orchestrating brain immune response and promoting neurodegeneration

PubMed Central

Yip, Ping Kei; Carrillo-Jimenez, Alejandro; King, Paul; Vilalta, Anna; Nomura, Koji; Chau, Chi Cheng; Egerton, Alexander Michael Scott; Liu, Zhuo-Hao; Shetty, Ashray Jayaram; Tremoleda, Jordi L.; Davies, Meirion; Deierborg, Tomas; Priestley, John V.; Brown, Guy Charles; Michael-Titus, Adina Teodora; Venero, Jose Luis; Burguillos, Miguel Angel

2017-01-01

Traumatic brain injury (TBI) is currently a major cause of morbidity and poor quality of life in Western society, with an estimate of 2.5 million people affected per year in Europe, indicating the need for advances in TBI treatment. Within the first 24 h after TBI, several inflammatory response factors become upregulated, including the lectin galectin-3. In this study, using a controlled cortical impact (CCI) model of head injury, we show a large increase in the expression of galectin-3 in microglia and also an increase in the released form of galectin-3 in the cerebrospinal fluid (CSF) 24 h after head injury. We report that galectin-3 can bind to TLR-4, and that administration of a neutralizing antibody against galectin-3 decreases the expression of IL-1β, IL-6, TNFα and NOS2 and promotes neuroprotection in the cortical and hippocampal cell populations after head injury. Long-term analysis demonstrated a significant neuroprotection in the cortical region in the galectin-3 knockout animals in response to TBI. These results suggest that following head trauma, released galectin-3 may act as an alarmin, binding, among other proteins, to TLR-4 and promoting inflammation and neuronal loss. Taking all together, galectin-3 emerges as a clinically relevant target for TBI therapy. PMID:28128358

The loss of luteal progesterone production in women is associated with a galectin switch via α2,6-sialylation of glycoconjugates.

PubMed

Nio-Kobayashi, Junko; Boswell, Lyndsey; Amano, Maho; Iwanaga, Toshihiko; Duncan, W Colin

2014-12-01

Luteal progesterone is fundamental for reproduction, but the molecular regulation of the corpus luteum (CL) in women remains unclear. Galectin-1 and galectin-3 bind to the sugar chains on cells to control key biological processes including cell function and fate. The expression and localization of LGALS1 and LGALS3 were analyzed by quantitative PCR and histochemical analysis, with special reference to α2,6-sialylation of glycoconjugates in carefully dated human CL collected across the menstrual cycle and after exposure to human chorionic gonadotrophin (hCG) in vivo. The effects of hCG and prostaglandin E2 on the expression of galectins and an α2,6-sialyltransferase 1 (ST6GAL1) in granulosa lutein cells were analyzed in vitro. Galectin-1 was predominantly localized to healthy granulosa lutein cells and galectin-3 was localized to macrophages and regressing granulosa lutein cells. Acute exposure to luteotrophic hormones (hCG and prostaglandin E2) up-regulated LGALS1 expression (P < .001). ST6GAL1, which catalyzes α2,6-sialylation to block galectin-1 binding, increased during luteolysis (P < .05) as did LGALS3 (P < .05). Luteotrophic hormones reduced ST6GAL1 and LGALS3 in vivo (P < .05) and in vitro (P < .001). There was an inverse correlation between the expression of ST6GAL1 and HSD3B1 (P < .01) and a distinct cellular relationship among α2,6-sialylation, 3β-hydroxysteroid dehydrogenase, and galectin expression. Galectin-1 is a luteotrophic factor whose binding is inhibited by α2,6-sialylation in the human CL during luteolysis. ST6GAL1 and galectin-3 expression is increased during luteolysis and associated with a loss of progesterone synthesis. Luteotrophic hormones differentially regulate galectin-1 and galectin-3/α2,6-sialylation in granulosa lutein cells, suggesting a novel galectin switch regulated by luteotrophic stimuli during luteolysis and luteal rescue.

Lactose-containing starburst dendrimers: influence of dendrimer generation and binding-site orientation of receptors (plant/animal lectins and immunoglobulins) on binding properties.

PubMed

André, S; Ortega, P J; Perez, M A; Roy, R; Gabius, H J

1999-11-01

Starburst glycodendrimers offer the potential to serve as high-affinity ligands for clinically relevant sugar receptors. In order to define areas of application, their binding behavior towards sugar receptors with differential binding-site orientation but identical monosaccharide specificity must be evaluated. Using poly(amidoamine) starburst dendrimers of five generations, which contain the p-isothiocyanato derivative of p-aminophenyl-beta-D-lactoside as ligand group, four different types of galactoside-binding proteins were chosen for this purpose, i.e., the (AB)(2)-toxic agglutinin from mistletoe, a human immunoglobulin G fraction, the homodimeric galectin-1 with its two binding sites at opposite ends of the jelly-roll-motif-harboring protein and monomeric galectin-3. Direct solid-phase assays with surface-immobilized glycodendrimers resulted in obvious affinity enhancements by progressive core branching for the plant agglutinin and less pronounced for the antibody and galectin-1. High density of binding of galectin-3 with modest affinity increases only from the level of the 32-mer onwards points to favorable protein-protein interactions of the monomeric lectin and a spherical display of the end groups without a major share of backfolding. When the inhibitory potency of these probes was evaluated as competitor of receptor binding to an immobilized neoglycoprotein or to asialofetuin, a marked selectivity was detected. The 32- and 64-mers were second to none as inhibitors for the plant agglutinin against both ligand-exposing matrices and for galectin-1 on the matrix with a heterogeneous array of interglycoside distances even on the per-sugar basis. In contrast, a neoglycoprotein with the same end group was superior in the case of the antibody and, less pronounced, monomeric galectin-3. Intimate details of topological binding-site presentation and the ligand display on different generations of core assembly are major operative factors which determine the potential of dendrimers for applications as lectin-targeting device, as attested by these observations.

Pectic polysaccharide from corn (Zea mays L.) effectively inhibited multi-step mediated cancer cell growth and metastasis.

PubMed

Jayaram, Smitha; Kapoor, Sabeeta; Dharmesh, Shylaja M

2015-06-25

Corn pectic polysaccharide (COPP) inhibited galectin-3 mediated hemagglutination at Minimum Inhibitory Concentration (MIC) of 4.08 μg/mL as opposed to citrus pectin (25 μg/mL), a well known galectin-3 inhibitor and lactose (4.16 μg/mL)--sugar specific to galectin-3. COPP effectively (72%) inhibited invasion and metastasis in experimental animals. In vivo results were substantiated by modulation of cancer specific markers such as galectin-3, which is a key molecule for initiation of metastatic cascade, vascular endothelial growth factor (VEGF) that enhances angiogenesis, matrix metalloproteinases 2 and 9 that are required for invasion, NF-κB, a transcription factor for proliferative potency of tumor cells and a phosphoglucoisomerase (PGI), the activity of which favors cancer cell growth. Structural characterization studies indicate the active component (relatively less acidic, 0.05 M ammonium carbonate, 160 kDa fraction) which showed antimetastatic potency in vitro with MIC of 0.09 μg/mL, and ∼ 45 fold increase in the activity when compared to that of COPP. Gas liquid chromatographic analysis indicated the presence of rhamnose (1%), arabinose (20%), xylose (3%), mannose (4%), galactose (54%) and uronic acid (10%) in different proportions. However, correlative data attributed galectin-3 inhibitory activity to enhanced levels of arabinose and galactose. FTIR, HPLC and NMR spectroscopic analysis further highlights that COPP is an arabinogalactan with methyl/ethyl esters. It is therefore suggested that the blockade of galectin-3 mediated lung metastasis appears to be a result of an inhibition of mixed functions induced during metastasis. The data signifies the importance of dietary carbohydrate as cancer-preventive agent. Although pectin digestibility and absorption are issues of concern, promising in vivo data provides evidence for the cancer preventive property of corn. The present study reveals for the first time a new component of corn, i.e.,--corn pectin with cancer preventive activity apart from corn starch that has been in wide use for multipurpose health benefits. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Role of Galectin-3 in Obesity and Impaired Glucose Homeostasis

PubMed Central

Menini, Stefano; Iacobini, Carla; Blasetti Fantauzzi, Claudia; Pesce, Carlo M.; Pugliese, Giuseppe

2016-01-01

Galectin-3 is an important modulator of several biological functions. It has been implicated in numerous disease conditions, particularly in the long-term complications of diabetes because of its ability to bind the advanced glycation/lipoxidation end products that accumulate in target organs and exert their toxic effects by triggering proinflammatory and prooxidant pathways. Recent evidence suggests that galectin-3 may also participate in the development of obesity and type 2 diabetes. It has been shown that galectin-3 levels are higher in obese and diabetic individuals and parallel deterioration of glucose homeostasis. Two studies in galectin-3 knockout mice fed a high-fat diet (HFD) have shown increased adiposity and adipose tissue and systemic inflammation associated with altered glucose homeostasis, suggesting that galectin-3 negatively modulates the responsiveness of innate and adaptive immunity to overnutrition. However, these studies have also shown that impaired glucose homeostasis occurs in galectin-3 knockout animals independently of obesity. Moreover, another study reported decreased weight and fat mass in HFD-fed galectin-3 knockout mice. In vitro, galectin-3 was found to stimulate differentiation of preadipocytes into mature adipocytes. Altogether, these data indicate that galectin-3 deserves further attention in order to clarify its role as a potential player and therapeutic target in obesity and type 2 diabetes. PMID:26770660

Galectin-3 in ambulatory patients with heart failure: results from the HF-ACTION study.

PubMed

Felker, G Michael; Fiuzat, Mona; Shaw, Linda K; Clare, Robert; Whellan, David J; Bettari, Luca; Shirolkar, Shailesh C; Donahue, Mark; Kitzman, Dalane W; Zannad, Faiez; Piña, Ileana L; O'Connor, Christopher M

2012-01-01

Galectin-3 is a soluble ß-galactoside-binding lectin released by activated cardiac macrophages. Elevated levels of galectin-3 have been found to be associated with adverse outcomes in patients with heart failure. We evaluated the association between galectin-3 and long-term clinical outcomes in ambulatory heart failure patients enrolled in the HF-ACTION study. HF-ACTION was a randomized, controlled trial of exercise training in patients with chronic heart failure caused by left ventricular systolic dysfunction. Galectin-3 was assessed at baseline in a cohort of 895 HF-ACTION subjects with stored plasma samples available. The association between galectin-3 and clinical outcomes was assessed using a series of Cox proportional hazards models. Higher galectin-3 levels were associated with other measures of heart failure severity, including higher New York Heart Association class, lower systolic blood pressure, higher creatinine, higher amino-terminal proB-type natriuretic peptide (NTproBNP), and lower maximal oxygen consumption. In unadjusted analysis, there was a significant association between elevated galectin-3 levels and hospitalization-free survival (unadjusted hazard ratio, 1.14 per 3-ng/mL increase in galectin-3; P<0.0001). In multivariable modeling, the prognostic impact of galectin-3 was significantly attenuated by the inclusion of other known predictors, and galectin-3 was no longer a significant predictor after the inclusion of NTproBNP. Galectin-3 is elevated in ambulatory heart failure patients and is associated with poor functional capacity and other known measures of heart failure severity. In univariate analysis, galectin-3 was significantly predictive of long-term outcomes, but this association did not persist after adjustment for other predictors, especially NTproBNP. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00047437.

Galectin-3 in Ambulatory Patients with Heart Failure: Results from the HF-ACTION Study

PubMed Central

Felker, G. Michael; Fiuzat, Mona; Shaw, Linda K.; Clare, Robert; Whellan, David J.; Bettari, Luca; Shirolkar, Shailesh C.; Donahue, Mark; Kitzman, Dalane W.; Zannad, Faiez; Piña, Ileana L.; O’Connor, Christopher M.

2011-01-01

Background Galectin-3 is a soluble ß-galactoside-binding lectin released by activated cardiac macrophages. Elevated levels of galectin-3 have been found to be associated with adverse outcomes in patients with heart failure. We evaluated the association between galectin-3 and long-term clinical outcomes in ambulatory heart failure patients enrolled in the HF-ACTION study. Methods and Results HF-ACTION was a randomized controlled trial of exercise training in patients with chronic heart failure due to left ventricular (LV) systolic dysfunction. Galectin-3 was assessed at baseline in a cohort of 895 HF-ACTION subjects with stored plasma samples available. The association between galectin-3 and clinical outcomes was assessed using a series of Cox proportional hazards models. Higher galectin-3 levels were associated with other measures of heart failure severity, including higher NYHA class, lower systolic blood pressure, higher creatinine, higher NTproBNP, and lower maximal oxygen consumption. In unadjusted analysis, there was a significant association between elevated galectin-3 levels and hospitalization-free survival (unadjusted hazard ratio = 1.14 per 3 ng/mL increase in galectin-3, P<0.0001). In multivariable modeling, the prognostic impact of galectin-3 was significantly attenuated by the inclusion of other known predictors and galectin-3 was no longer a significant predictor after the inclusion of NTproBNP. Conclusions Galectin-3 is elevated in ambulatory heart failure patients and is associated with poor functional capacity and other known measures of heart failure severity. In univariate analysis, galectin-3 was significantly predictive of long-term outcomes, but this association did not persist after adjustment for other predictors, especially NTproBNP. PMID:22016505

Serum Galectin-3 and Poor Outcomes Among Patients With Acute Ischemic Stroke.

PubMed

Wang, Aili; Zhong, Chongke; Zhu, Zhengbao; Xu, Tian; Peng, Yanbo; Xu, Tan; Peng, Hao; Chen, Chung-Shiuan; Wang, Jinchao; Ju, Zhong; Li, Qunwei; Geng, Deqin; Sun, Yingxian; Zhang, Jianhui; Yuan, Xiaodong; Chen, Jing; Zhang, Yonghong; He, Jiang

2018-01-01

Elevated galectin-3 has been associated with atherosclerosis and poor outcomes in patients with heart failure. However, it remains unclear whether galectin-3 has any effect on the poor outcomes of ischemic stroke. The aim of the present study was to examine the association between galectin-3 with poor outcomes among patients with acute ischemic stroke. Serum galectin-3 was measured in 3082 patients with acute ischemic stroke. The primary outcome was a combination of death or major disability (modified Rankin Scale score, ≥3) at 3 months after stroke. Compared with the lowest quartile of galectin-3, multivariate adjusted odds ratios (95% confidence intervals) for the highest quartile of galectin-3 were 1.55 (1.15-2.09) for composite outcome, 2.10 (0.89-4.95) for death, and 1.43 (1.05-1.93) for major disability. The addition of galectin-3 to the conventional risk factors significantly improved prediction of the combined outcome of death or major disability in patients with ischemic stroke (net reclassification index, 18.9%; P <0.001; integrated discrimination improvement, 0.4%; P =0.001). Higher levels of serum galectin-3 were independently associated with increased risk of death or major disability after stroke onset, suggesting that galectin-3 may have prognostic value in poor outcomes of ischemic stroke. © 2017 American Heart Association, Inc.

Galectin-3 Is a Target for Proteases Involved in the Virulence of Staphylococcus aureus.

PubMed

Elmwall, Jonas; Kwiecinski, Jakub; Na, Manli; Ali, Abukar Ahmed; Osla, Veronica; Shaw, Lindsey N; Wang, Wanzhong; Sävman, Karin; Josefsson, Elisabet; Bylund, Johan; Jin, Tao; Welin, Amanda; Karlsson, Anna

2017-07-01

Staphylococcus aureus is a major cause of skin and soft tissue infection. The bacterium expresses four major proteases that are emerging as virulence factors: aureolysin (Aur), V8 protease (SspA), staphopain A (ScpA), and staphopain B (SspB). We hypothesized that human galectin-3, a β-galactoside-binding lectin involved in immune regulation and antimicrobial defense, is a target for these proteases and that proteolysis of galectin-3 is a novel immune evasion mechanism. Indeed, supernatants from laboratory strains and clinical isolates of S. aureus caused galectin-3 degradation. Similar proteolytic capacities were found in Staphylococcus epidermidis isolates but not in Staphylococcus saprophyticus Galectin-3-induced activation of the neutrophil NADPH oxidase was abrogated by bacterium-derived proteolysis of galectin-3, and SspB was identified as the major protease responsible. The impact of galectin-3 and protease expression on S. aureus virulence was studied in a murine skin infection model. In galectin-3 +/+ mice, SspB-expressing S. aureus caused larger lesions and resulted in higher bacterial loads than protease-lacking bacteria. No such difference in bacterial load or lesion size was detected in galectin-3 -/- mice, which overall showed smaller lesion sizes than the galectin-3 +/+ animals. In conclusion, the staphylococcal protease SspB inactivates galectin-3, abrogating its stimulation of oxygen radical production in human neutrophils and increasing tissue damage during skin infection. Copyright © 2017 American Society for Microbiology.

Trichomonas vaginalis Lipophosphoglycan Exploits Binding to Galectin-1 and -3 to Modulate Epithelial Immunity*

PubMed Central

Fichorova, Raina N.; Yamamoto, Hidemi S.; Fashemi, Titilayo; Foley, Evan; Ryan, Stanthia; Beatty, Noah; Dawood, Hassan; Hayes, Gary R.; St-Pierre, Guillaume; Sato, Sachiko; Singh, Bibhuti N.

2016-01-01

Trichomoniasis is the most common non-viral sexually transmitted infection caused by the vaginotropic extracellular protozoan parasite Trichomonas vaginalis. The infection is recurrent, with no lasting immunity, often asymptomatic, and linked to pregnancy complications and risk of viral infection. The molecular mechanisms of immune evasion by the parasite are poorly understood. We demonstrate that galectin-1 and -3 are expressed by the human cervical and vaginal epithelial cells and act as pathogen-recognition receptors for the ceramide phosphoinositol glycan core (CPI-GC) of the dominant surface protozoan lipophosphoglycan (LPG). We used an in vitro model with siRNA galectin knockdown epithelial clones, recombinant galectins, clinical Trichomonas isolates, and mutant protozoan derivatives to dissect the function of galectin-1 and -3 in the context of Trichomonas infection. Galectin-1 suppressed chemokines that facilitate recruitment of phagocytes, which can eliminate extracellular protozoa (IL-8) or bridge innate to adaptive immunity (MIP-3α and RANTES (regulated on activation normal T cell expressed and secreted)). Silencing galectin-1 increased and adding exogenous galectin-1 suppressed chemokine responses to Trichomonas or CPI-GC/LPG. In contrast, silencing galectin-3 reduced IL-8 response to LPG. Live Trichomonas depleted the extracellular levels of galectin-3. Clinical isolates and mutant Trichomonas CPI-GC that had reduced affinity to galectin-3 but maintained affinity to galectin-1 suppressed chemokine expression. Thus via CPI-GC binding, Trichomonas is capable of regulating galectin bioavailability and function to the benefit of its parasitic survival. These findings suggest novel approaches to control trichomoniasis and warrant further studies of galectin-binding diversity among clinical isolates as a possible source for symptom disparity in parasitic infections. PMID:26589797

Pattern of galectins expression in actinic cheilitis with different risks of malignant transformation.

PubMed

Lopes, Maria Luiza Diniz de Sousa; Nonaka, Cassiano Francisco Weege; Queiroz, Lélia Maria Guedes; de Souza, Lélia Batista; Miguel, Márcia Cristina da Costa; da Silveira, Éricka Janine Dantas

2016-09-01

Actinic cheilitis (AC) is a chronic inflammatory lesion that in some situations can turn into squamous cell carcinoma of the lip. The molecular mechanisms involved in this process are not yet completely understood. This study aimed to investigate the expression pattern of galectins in actinic cheilitis according to the histopathological grading. Immunoexpression of galectin-1, galectin-3, galectin-7, and galectin-9 was semiquantitatively analyzed in 65 cases of actinic cheilitis graded as low risk (n = 40) or high risk (n = 25) of malignant transformation. Association between the location of the galectins in the cellular compartments and histopathological grading was analyzed. Galectin-1 was mainly observed in the cell cytoplasm, and was elevated (score 3) in 60% of cases, regardless of the histopathological grade (P > 0.05). Galectin-3 expression was higher in high-risk group than in the low-risk group (P < 0.05), with a predominant expression in the cytoplasm and nucleus of low-risk (67.5%), and only in the cytoplasm of high-risk cases (60%) (P < 0.05). Galectin-7 expression did not show significant differences between low-risk and high-risk groups (P > 0.05). With respect to galectin-9, 89.2% of cases were positive, showing decrease in median of scores as there was an increase in histological grade (P < 0.001), with predominant expression in the nucleus and cytoplasm. This study is the first indication of galectins involvement in the pathogenesis and morphologic progression of actinic cheilitis, particularly galectin-3 and galectin-9. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Galectin-3 as a novel regulator of osteoblast-osteoclast interaction and bone homeostasis.

PubMed

Simon, Dominic; Derer, Anja; Andes, Fabian T; Lezuo, Patrick; Bozec, Aline; Schett, Georg; Herrmann, Martin; Harre, Ulrike

2017-12-01

Bone tissue undergoes permanent and lifelong remodeling with a concerted action of bone-building osteoblasts and bone-resorbing osteoclasts. A precise cooperation between those two cell types is critical in the complex process of bone renewal. Galectin-3 is a member of the β-galactoside-binding lectin family playing multiple roles in cell growth, differentiation and aggregation. As it has been described to be expressed in bone, galectin-3 might influence bone homeostasis by regulating the function and/or interplay of osteoblasts and osteoclasts. Here, we investigated the role of galectin-3 in osteoclastogenesis and osteoblast-osteoclast interactions. Bone histomorphometric analysis and μCT measurements revealed a decreased trabecular bone volume and an increased osteoclast number in 12weeks old male galectin-3 knockout mice compared to wildtype littermates. Galectin-3 deficient bone marrow cells displayed a higher osteoclastogenic capacity in ex vivo differentiation assays, associated with elevated TRAF6 mRNA levels, suggesting an intrinsic inhibition of osteoclastogenesis by galectin-3 interfering with RANKL-mediated signaling. Furthermore, the addition of extracellular galectin-3 to murine or human osteoclastogenesis assays inhibited osteoclast formation and osteoclast numbers were higher in co-culture assays with galectin-3 deficient osteoblasts. In conclusion, our data suggest the secretion of galectin-3 as a novel mechanism for osteoblasts to control osteoclastogenesis and to maintain trabecular bone homeostasis independently of the RANKL/OPG-axis. Copyright © 2017 Elsevier Inc. All rights reserved.

Galectin-3 in M2 macrophages plays a protective role in resolution of neuropathology in brain parasitic infection by regulating neutrophil turnover.

PubMed

Quenum Zangbede, Fredice O; Chauhan, Arun; Sharma, Jyotika; Mishra, Bibhuti B

2018-06-26

Macrophages/microglia with M2- activation phenotype are thought to play an important anti-inflammatory and tissue reparative functions in the brain, yet the molecular basis of their functions in the central nervous system (CNS) remain to be clearly defined. In a preclinical model of neurocysticercosis using brain infection with a parasite Mesocestoides corti , we previously reported the presence of large numbers of M2 cells in the CNS. In this study using female mice, we report that M2 macrophages in the parasite-infected brain display abundant galectin-3 expression. Disease severity was increased in Galectin-3 -/- mice correlating with increased neurological defects, augmented cell death and, importantly, massive accumulation of neutrophils and M2 macrophages in the CNS of these mice. Because neutrophil clearance by efferocytosis is an important function of M2 macrophages, we investigated a possible role of galectin-3 in this process. Indeed, galectin-3 deficient M2 macrophages exhibited a defect in efferocytic clearance of neutrophils in-vitro. Furthermore, adoptive transfer of M2 macrophages from Galectin-3 sufficient WT mice reduced neutrophilia in the CNS and ameliorated disease severity in parasite-infected Galectin-3 -/- mice. Together, these results demonstrate for the first time a novel role of galectin-3 in M2 macrophage function in neutrophil turnover and resolution of inflammatory pathology in the CNS. This likely will have implications in neurocysticercosis and neuro-inflammatory diseases. SIGNIFICANCE STATEMENT Macrophages/microglia with M1-activation phenotype are thought to promote CNS pathology, whereas M2-anti-inflammatory phenotype promote CNS repair. However, the mechanisms regulating M2 cell protective functions in the CNS microenvironment are undefined. Quenum Zangbede et. al., report that helminth infection of the brain induces an increased expression of galectin-3 in M2 macrophages accumulated in the CNS. Using multiple experimental models in vivo and in vitro , they show that galectin-3 in M2 macrophages functions to clear neutrophils accumulated in the CNS. Importantly, galectin-3 in M2 macrophages plays a central role in the containment of neuropathology and disease severity. These results provide a direct mechanistic evidence of the protective function of M2- macrophages in the CNS. Copyright © 2018 the authors.

Galectin-3 drives oligodendrocyte differentiation to control myelin integrity and function

PubMed Central

Pasquini, L A; Millet, V; Hoyos, H C; Giannoni, J P; Croci, D O; Marder, M; Liu, F T; Rabinovich, G A; Pasquini, J M

2011-01-01

Galectins control critical pathophysiological processes, including the progression and resolution of central nervous system (CNS) inflammation. In spite of considerable progress in dissecting their role within lymphoid organs, their functions within the inflamed CNS remain elusive. Here, we investigated the role of galectin–glycan interactions in the control of oligodendrocyte (OLG) differentiation, myelin integrity and function. Both galectin-1 and -3 were abundant in astrocytes and microglia. Although galectin-1 was abundant in immature but not in differentiated OLGs, galectin-3 was upregulated during OLG differentiation. Biochemical analysis revealed increased activity of metalloproteinases responsible for cleaving galectin-3 during OLG differentiation and modulating its biological activity. Exposure to galectin-3 promoted OLG differentiation in a dose- and carbohydrate-dependent fashion consistent with the ‘glycosylation signature' of immature versus differentiated OLG. Accordingly, conditioned media from galectin-3-expressing, but not galectin-3-deficient (Lgals3−/−) microglia, successfully promoted OLG differentiation. Supporting these findings, morphometric analysis showed a significant decrease in the frequency of myelinated axons, myelin turns (lamellae) and g-ratio in the corpus callosum and striatum of Lgals3−/− compared with wild-type (WT) mice. Moreover, the myelin structure was loosely wrapped around the axons and less smooth in Lgals3−/− mice versus WT mice. Behavior analysis revealed decreased anxiety in Lgals3−/− mice similar to that observed during early demyelination induced by cuprizone intoxication. Finally, commitment toward the oligodendroglial fate was favored in neurospheres isolated from WT but not Lgals3−/− mice. Hence, glial-derived galectin-3, but not galectin-1, promotes OLG differentiation, thus contributing to myelin integrity and function with critical implications in the recovery of inflammatory demyelinating disorders. PMID:21566659

The change of plasma galectin-3 concentrations after traumatic brain injury.

PubMed

Shen, Yong-Feng; Yu, Wen-Hua; Dong, Xiao-Qiao; Du, Quan; Yang, Ding-Bo; Wu, Gang-Qun; Zhang, Zu-Yong; Wang, Hao; Jiang, Li

2016-05-01

Galectin-3 plays a significant role in microglia activation. Its increased circulating concentration has been associated with some inflammatory diseases. In-hospital major adverse events (IMAEs), including acute traumatic coagulopathy, progressive hemorrhagic injury and posttraumatic cerebral infarction, have high prevalence and are strong predictors of mortality after severe traumatic brain injury (STBI). The present study was designed to investigate the relationships between plasma galectin-3 concentrations and trauma severity, in-hospital mortality and IMAEs following STBI. Plasma galectin-3 concentrations of 100 STBI patients and 100 controls were determined. Diagnosis of progressive hemorrhagic injury and posttraumatic cerebral infarction was made on the follow-up computerized tomography scan. Acute traumatic coagulopathy was defined based on coagulation test. Plasma galectin-3 concentrations were significantly higher in patients as compared to controls and also associated highly with Glasgow Coma Scale scores and plasma C-reactive protein concentrations. Galectin-3 emerged as an independent predictor for in-hospital mortality and IMAEs. Areas under receiver operating characteristic curve of plasma galectin-3 concentrations were similar to those of Glasgow Coma Scale scores for prediction of in-hospital morality and IMAEs. Plasma galectin-3 concentrations have close relation to inflammation, trauma severity and clinical outcome, suggesting that galectin-3 should have the potential to be a good prognostic biomarker after STBI. Copyright © 2016 Elsevier B.V. All rights reserved.

Tumor suppressor p16 INK4a: Downregulation of galectin-3, an endogenous competitor of the pro-anoikis effector galectin-1, in a pancreatic carcinoma model.

PubMed

Sanchez-Ruderisch, Hugo; Fischer, Christian; Detjen, Katharina M; Welzel, Martina; Wimmel, Anja; Manning, Joachim C; André, Sabine; Gabius, Hans-Joachim

2010-09-01

The tumor suppressor p16(INK4a) has functions beyond cell-cycle control via cyclin-dependent kinases. A coordinated remodeling of N- and O-glycosylation, and an increase in the presentation of the endogenous lectin galectin-1 sensing these changes on the surface of p16(INK4a)-expressing pancreatic carcinoma cells (Capan-1), lead to potent pro-anoikis signals. We show that the p16(INK4a)-dependent impact on growth-regulatory lectins is not limited to galectin-1, but also concerns galectin-3. By monitoring its expression in relation to p16(INK4a) status, as well as running anoikis assays with galectin-3 and cell transfectants with up- or downregulated lectin expression, a negative correlation between anoikis and the presence of this lectin was established. Nuclear run-off and northern blotting experiments revealed an effect of the presence of p16(INK4a) on steady-state levels of galectin-3-specific mRNA that differed from decreasing the transcriptional rate. On the cell surface, galectin-3 interferes with galectin-1, which initiates signaling toward its pro-anoikis activity via caspase-8 activation. The detected opposite effects of p16(INK4a) at the levels of growth-regulatory galectins-1 and -3 shift the status markedly towards the galectin-1-dependent pro-anoikis activity. A previously undescribed orchestrated fine-tuning of this effector system by a tumor suppressor is discovered.

Depression in type 1 diabetes was associated with high levels of circulating galectin-3

PubMed Central

Melin, Eva Olga; Dereke, Jonatan; Thunander, Maria; Hillman, Magnus

2018-01-01

Objective Neuroinflammatory responses are implicated in depression. The aim was to explore whether depression in patients with type 1 diabetes (T1D) was associated with high circulating galectin-3, controlling for metabolic variables, s-creatinine, life style factors, medication and cardiovascular complications. Design Cross-sectional. Methods Participants were T1D patients (n = 283, 56% men, age 18–59 years, diabetes duration ≥1 year). Depression was assessed by Hospital Anxiety and Depression Scale-depression subscale. Blood samples, anthropometrics and blood pressure were collected, and supplemented with data from medical records and the Swedish National Diabetes Registry. Galectin-3 ≥2.562 µg/l, corresponding to the 85th percentile, was defined as high galectin-3. Results Median (quartile1, quartile3) galectin-3 (µg/l) was 1.3 (0.8, 2.9) for the 30 depressed patients, and 0.9 (0.5, 1.6) for the 253 non-depressed, P = 0.009. Depression was associated with high galectin-3 in all the 283 patients (adjusted odds ratio (AOR) 3.5), in the 161 men (AOR 3.4), and in the 122 women (AOR 3.9). HbA1c, s-lipids, s-creatinine, blood pressure, obesity, smoking, physical inactivity, cardiovascular complications and drugs (antihypertensive, lipid lowering, oral antidiabetic drugs and antidepressants) were not associated with high galectin-3. Conclusions This is the first study to show an association between depression and galectin-3. Depression was the only explored parameter associated with high circulating galectin-3 levels in 283 T1D patients. High galectin-3 levels might contribute to the increased risk for Alzheimer’s disease, cardiovascular and all-cause mortality observed in persons with depression. Potentially, in the future, treatment targeting galactin-3 might improve the prognosis for patients with high galectin-3 levels. PMID:29760188

Increased Expressions of Plasma Galectin-3 in Patients with Amyotrophic Lateral Sclerosis

PubMed Central

Yan, Jun; Xu, Yun; Zhang, Li; Zhao, Hui; Jin, Ling; Liu, Wei-Guo; Weng, Lei-Hua; Li, Zuo-Han; Chen, Ling

2016-01-01

Background: High expressions of galectin-3 were identified recently in the end stage of amyotrophic lateral sclerosis (ALS) patients, which suggested that immune reactivity and inflammatory mechanisms might play an important role in the pathogenesis of ALS. The purpose of this study was to investigate plasma galectin-3 levels in different groups and stages of ALS patients and the association with related clinical characteristics. Methods: A total of 51 patients with ALS and 60 normal controls (NCs) were recruited in this study. Plasma galectin-3 levels were determined using the enzyme-linked immunosorbent assay. Patients with ALS were divided into several groups according to their clinical characteristics: gender, type of disease onset, duration of disease, and clinical conditions of disease. Statistical analyses of the differences of galectin-3 levels between groups and the association with the clinical characteristics of disease were performed. Results: As compared with the NCs (201.64 [22.35–401.63] ng/ml), plasma galectin-3 levels were significantly elevated in the patients with duration >12 months (341.17 [69.12–859.22] ng/ml, P < 0.05), and the patients with limb onset of disease (254.14 [69.12–859.22] ng/ml, P < 0.05); however, no difference was found in the patients with duration ≤12 months (250.62 [109.77–334.92] ng/ml, P > 0.05), and the patients with bulbar onset of disease (251.79 [109.20–404.76] ng/ml, P > 0.05). In addition, galectin-3 levels were significantly increased in the female patients (263.27 [123.32–859.22] ng/ml, P < 0.05) while no difference was found in the male patients (220.39 [69.12–748.73] ng/ml, P > 0.05). The further statistical analyses showed that plasma galectin-3 levels were positively correlated with the duration of disease (r = 0.293, P = 0.037). Conclusions: Plasma galectin-3 levels were significantly increased in ALS patients with limb onset of disease, especially in ALS female patients, and positively correlated with the duration of disease, which suggested that plasma galectin-3 might be an interesting and useful factor associated with ALS. PMID:27900991

Extracellular galectin-1 enhances adhesion to and invasion of oral epithelial cells by Porphyromonas gingivalis.

PubMed

Tamai, Riyoko; Kobayashi-Sakamoto, Michiyo; Kiyoura, Yusuke

2018-03-15

Galectin-1 and galectin-3 are C-type lectin receptors that bind to lipopolysaccharide in the cell wall of gram-negative bacteria. In this study, we investigated the effects of galectin-1 and galectin-3 on adhesion to and invasion of the human gingival epithelial cell line Ca9-22 by Porphyromonas gingivalis, a periodontal pathogenic gram-negative bacterium. Recombinant galectin-1, but not galectin-3, enhanced P. gingivalis adhesion and invasion, although both galectins bound similarly to P. gingivalis. Flow cytometry also revealed that Ca9-22 cells express low levels of galectin-1 and moderate levels of galectin-3. Ca9-22 cells in which galectin-3 was knocked-down did not exhibit enhanced P. gingivalis adhesion and invasion. Similarly, specific antibodies to galectin-1 and galectin-3 did not inhibit P. gingivalis adhesion and invasion. These results suggest that soluble galectin-1, but not galectin-3, may exacerbate periodontal disease by enhancing the adhesion to and invasion of host cells by periodontal pathogenic bacteria.

Immunohistochemical localization of galectin-3 in the pig retina during postnatal development

PubMed Central

Kim, Jihoon; Moon, Changjong; Ahn, Meejung; Joo, Hong-Gu; Jin, Jae-Kwang

2009-01-01

Purpose The differential level and localization of galectin-3 protein were examined in the retinas of two-day-old pigs and six-month-old pigs. Methods The retinas sampled from two-day-old and six-month-old pigs were analyzed by western blot and immunohistochemistry. Results western blot analysis detected galectin-3 in both age groups, although the levels were significantly higher in six-month-old pigs. Immunohistochemical staining showed that galectin-3 was localized in the retinas of both two-day-old pigs and six-month-old pigs; the galectin-3 immunostaining was more intense in the six-month-old pig retina, as shown in the western blot analysis. Galectin-3 was expressed in glial cells, particularly in glutamine synthetase-positive Müller cells and their processes, across all retina layers in both age groups; however, it was not found in ganglion cells of the ganglion cell layer or neuronal cells of the inner and outer nuclear cell layers in either age group. Conclusions This is the first demonstration that galectin-3 is detected in the retinas of two-day-old pigs and that the expression in Müller cells increases with postnatal development. PMID:19816601

Galectin-1 is associated with poor prognosis in patients with cutaneous head and neck cancer with perineural spread.

PubMed

Chawla, Sharad; Warren, Timothy A; Wockner, Leesa F; Lambie, Duncan L J; Brown, Ian S; Martin, Thomas P C; Khanna, Rajiv; Leggatt, Graham R; Panizza, Benedict J

2016-02-01

Spread of head and neck cancer along the cranial nerves is often a lethal complication of this tumour. Current treatment options include surgical resection and/or radiotherapy, but recurrence is a frequent event suggesting that our understanding of this tumour and its microenvironment is incomplete. In this study, we have analysed the nature of the perineural tumour microenvironment by immunohistochemistry with particular focus on immune cells and molecules, which might impair anti-tumour immunity. Moderate to marked lymphocyte infiltrates were present in 58.8% of the patient cohort including T cells, B cells and FoxP3-expressing T cells. While human leukocyte antigen (HLA) class I and more variably HLA class II were expressed on the tumour cells, this did not associate with patient survival or recurrence. In contrast, galectin-1 staining within lymphocyte areas of the tumour was significantly associated with a poorer patient outcome. Given the known role of galectin-1 in immune suppression, the data suggest that galectin inhibitors might improve the prognosis of patients with perineural spread of cancer.

Differential Spatiotemporal Patterns of Galectin Expression are a Hallmark of Endotheliochorial Placentation.

PubMed

Conrad, Melanie L; Freitag, Nancy; Diessler, Mónica E; Hernandez, Rocío; Barrientos, Gabriela; Rose, Matthias; Casas, Luciano A; Barbeito, Claudio G; Blois, Sandra M

2016-03-01

Galectins influence the progress of pregnancy by regulating key processes associated with embryo-maternal cross talk, including angiogenesis and placentation. Galectin family members exert multiple roles in the context of hemochorial and epitheliochorial placentation; however, the galectin prolife in endotheliochorial placenta remains to be investigated. Here, we used immunohistochemistry to analyze galectin (gal)-1, gal-3 and gal-9 expression during early and late endotheliochorial placentation in two different species (dogs and cats). We found that during early feline gestation, all three galectin members were more strongly expressed on trophoblast and maternal vessels compared to the decidua. This was accompanied by an overall decrease of gal-1, gal-3 and gal-9 expressions in late feline gestation. In canine early pregnancy, we observed that gal-1 and gal-9 were expressed strongly in cytotrophoblast (CTB) cells compared to gal-3, and no galectin expression was observed in syncytiotrophoblast (STB) cells. Progression of canine gestation was accompanied by increased gal-1 and gal-3 expressions on STB cells, whereas gal-9 expression remained similar in CTB and STB. These data suggest that both the maternal and fetal compartments are characterized by a spatiotemporal regulation of galectin expression during endotheliochorial placentation. This strongly suggests the involvement of the galectin family in important developmental processes during gestation including immunemodulation, trophoblast invasion and angiogenesis. A conserved functional role for galectins during mammalian placental development emerges from these studies. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Interaction of galectin-3 with MUC1 on cell surface promotes EGFR dimerization and activation in human epithelial cancer cells.

PubMed

Piyush, Tushar; Chacko, Anisha R; Sindrewicz, Paulina; Hilkens, John; Rhodes, Jonathan M; Yu, Lu-Gang

2017-11-01

Epidermal growth factor receptor (EGFR) is an important regulator of epithelial cell growth and survival in normal and cancerous tissues and is a principal therapeutic target for cancer treatment. EGFR is associated in epithelial cells with the heavily glycosylated transmembrane mucin protein MUC1, a natural ligand of galectin-3 that is overexpressed in cancer. This study reveals that the expression of cell surface MUC1 is a critical enhancer of EGF-induced EGFR activation in human breast and colon cancer cells. Both the MUC1 extracellular and intracellular domains are involved in EGFR activation but the predominant influence comes from its extracellular domain. Binding of galectin-3 to the MUC1 extracellular domain induces MUC1 cell surface polarization and increases MUC1-EGFR association. This leads to a rapid increase of EGFR homo-/hetero-dimerization and subsequently increased, and also prolonged, EGFR activation and signalling. This effect requires both the galectin-3 C-terminal carbohydrate recognition domain and its N-terminal ligand multi-merization domain. Thus, interaction of galectin-3 with MUC1 on cell surface promotes EGFR dimerization and activation in epithelial cancer cells. As MUC1 and galectin-3 are both commonly overexpressed in most types of epithelial cancers, their interaction and impact on EGFR activation likely makes important contribution to EGFR-associated tumorigenesis and cancer progression and may also influence the effectiveness of EGFR-targeted cancer therapy.

Possible Role of Inflammation and Galectin-3 in Brain Injury after Subarachnoid Hemorrhage

PubMed Central

2018-01-01

Aneurysmal subarachnoid hemorrhage (SAH) is known as one of the most devastating diseases in the central nervous system. In the past few decades, research on SAH has focused on cerebral vasospasm to prevent post-SAH delayed cerebral ischemia (DCI) and to improve outcomes. However, increasing evidence has suggested that early brain injury (EBI) is an important mechanism contributing to DCI, cerebral vasospasm as well as poor outcomes. Though the mechanism of EBI is very complex, inflammation is thought to play a pivotal role in EBI. Galectin-3 is a unique chimera type in the galectin family characterized by its β-galactoside-binding lectin, which mediates various pathologies, such as fibrosis, cell adhesion, and inflammation. Recently, two clinical studies revealed galectin-3 to be a possible prognostic biomarker in SAH patients. In addition, our recent report suggested that higher acute-stage plasma galectin-3 levels correlated with subsequent development of delayed cerebral infarction that was not associated with vasospasm in SAH patients. We review the possible role and molecular mechanisms of inflammation as well as galectin-3 in brain injuries, especially focusing on EBI after SAH, and discuss galectin-3 as a potential new therapeutic or research target in post-SAH brain injuries. PMID:29414883

Lectins Offer New Perspectives in the Development of Macrophage-Targeted Therapies for COPD/Emphysema

PubMed Central

Mukaro, Violet R.; Bylund, Johan; Hodge, Greg; Holmes, Mark; Jersmann, Hubertus; Reynolds, Paul N.; Hodge, Sandra

2013-01-01

We have previously shown that the defective ability of alveolar macrophages (AM) to phagocytose apoptotic cells (‘efferocytosis’) in chronic obstructive pulmonary disease/emphysema (COPD) could be therapeutically improved using the C-type lectin, mannose binding lectin (MBL), although the exact mechanisms underlying this effect are unknown. An S-type lectin, galectin-3, is also known to regulate macrophage phenotype and function, via interaction with its receptor CD98. We hypothesized that defective expression of galectin/CD98 would be associated with defective efferocytosis in COPD and that mechanisms would include effects on cytoskeletal remodeling and macrophage phenotype and glutathione (GSH) availability. Galectin-3 was measured by ELISA in BAL from controls, smokers and current/ex-smokers with COPD. CD98 was measured on AM using flow cytometry. We assessed the effects of galectin-3 on efferocytosis, CD98, GSH, actin polymerisation, rac activation, and the involvement of PI3K (using β-actin probing and wortmannin inhibition) in vitro using human AM and/or MH-S macrophage cell line. Significant decreases in BAL galectin-3 and AM CD98 were observed in BAL from both current- and ex-smoker COPD subjects vs controls. Galectin 3 increased efferocytosis via an increase in active GTP bound Rac1. This was confirmed with β-actin probing and the role of PI3K was confirmed using wortmannin inhibition. The increased efferocytosis was associated with increases in available glutathione and expression of CD98. We provide evidence for a role of airway lectins in the failed efferocytosis in COPD, supporting their further investigation as potential macrophage-targeted therapies. PMID:23441163

A Genome-Wide Association Study of Circulating Galectin-3

PubMed Central

van Veldhuisen, Dirk J.; Westra, Harm-Jan; Bakker, Stephan J. L.; Gansevoort, Ron T.; Muller Kobold, Anneke C.; van Gilst, Wiek H.; Franke, Lude

2012-01-01

Galectin-3 is a lectin involved in fibrosis, inflammation and proliferation. Increased circulating levels of galectin-3 have been associated with various diseases, including cancer, immunological disorders, and cardiovascular disease. To enhance our knowledge on galectin-3 biology we performed the first genome-wide association study (GWAS) using the Illumina HumanCytoSNP-12 array imputed with the HapMap 2 CEU panel on plasma galectin-3 levels in 3,776 subjects and follow-up genotyping in an additional 3,516 subjects. We identified 2 genome wide significant loci associated with plasma galectin-3 levels. One locus harbours the LGALS3 gene (rs2274273; P = 2.35×10−188) and the other locus the ABO gene (rs644234; P = 3.65×10−47). The variance explained by the LGALS3 locus was 25.6% and by the ABO locus 3.8% and jointly they explained 29.2%. Rs2274273 lies in high linkage disequilibrium with two non-synonymous SNPs (rs4644; r2 = 1.0, and rs4652; r2 = 0.91) and wet lab follow-up genotyping revealed that both are strongly associated with galectin-3 levels (rs4644; P = 4.97×10−465 and rs4652 P = 1.50×10−421) and were also associated with LGALS3 gene-expression. The origins of our associations should be further validated by means of functional experiments. PMID:23056639

Galectin-3 and N-acetylglucosamine promote myogenesis and improve skeletal muscle function in the mdx model of Duchenne muscular dystrophy.

PubMed

Rancourt, Ann; Dufresne, Sébastien S; St-Pierre, Guillaume; Lévesque, Julie-Christine; Nakamura, Haruka; Kikuchi, Yodai; Satoh, Masahiko S; Frenette, Jérôme; Sato, Sachiko

2018-06-12

The muscle membrane, sarcolemma, must be firmly attached to the basal lamina. The failure of proper attachment results in muscle injury, which is the underlying cause of Duchenne muscular dystrophy (DMD), in which mutations in the dystrophin gene disrupts the firm adhesion. In patients with DMD, even moderate contraction causes damage, leading to progressive muscle degeneration. The damaged muscles are repaired through myogenesis. Consequently, myogenesis is highly active in patients with DMD, and the repeated activation of myogenesis leads to the exhaustion of the myogenic stem cells. Therefore, approaches to reducing the risk of the exhaustion are to develop a treatment that strengthens the interaction between the sarcolemma and the basal lamina and increases the efficiency of the myogenesis. Galectin-3 is an oligosaccharide-binding protein and is known to be involved in cell-cell interactions and cell-matrix interactions. Galectin-3 is expressed in myoblasts and skeletal muscle, although its function in muscle remains elusive. In this study, we found evidence that galectin-3 and the monosaccharide N-acetylglucosamine, which increases the synthesis of binding partners (oligosaccharides) of galectin-3, promote myogenesis in vitro. Moreover, in the mdx mouse model of DMD, treatment with N-acetylglucosamine increased muscle-force production. The results suggest that treatment with N-acetylglucosamine might mitigate the burden of DMD.-Rancourt, A., Dufresne, S. S., St-Pierre, G., Lévesque, J.-C., Nakamura, H., Kikuchi, Y., Satoh, M. S., Frenette, J., Sato, S. Galectin-3 and N-acetylglucosamine promote myogenesis and improve skeletal muscle function in the mdx model of Duchenne muscular dystrophy.

Cord blood neutrophils display a galectin-3 responsive phenotype accentuated by vaginal delivery

PubMed Central

2013-01-01

Background Term neonates are at increased risk of infections due to undeveloped immune mechanisms, and proper neutrophil function is important for perinatal immune defence. Galectin-3, an endogenous β-galactoside-binding lectin, is emerging as an inflammatory mediator and we have previously shown that primed/activated, but not resting, adult neutrophils respond to this lectin by production of reactive oxygen species (ROS). We investigated if galectin-3 is of importance in perinatal immune defence, focusing on plasma levels and neutrophil responsiveness. Methods Neutrophils were isolated from peripheral blood of healthy adults and cord blood (CB) after elective Caesarean section (CSCB) and vaginal delivery (VDCB). ROS production was measured by chemiluminescence, L-selectin expression by flow cytometry, and interleukin-8 (IL-8) and galectin-3 concentrations by ELISA. Statistical evaluations were performed using the Mann–Whitney test. Results In response to galectin-3, CSCB neutrophils showed a small but clear ROS production not evident in adult cells, signifying that neonatal neutrophils exist in a primed state. IL-8 production was elevated in CSCB cells while L-selectin exposure was equal to adult cells. Comparing CSCB to VDCB neutrophils, the latter showed an extensive galectin-3 responsiveness, indicating that the degree of priming is dependent on mode of delivery. VDCB neutrophils were increasingly prone to shed L-selectin, while the amount of IL-8 was similar to CSCB cells. The endogenous galectin-3 levels were higher in neonatal as compared to adult plasma, unaffected by mode of delivery. Conclusions Neutrophils enter a pre-primed state already in the fetus. Upon exposure to the inflammatory stimuli that are associated with labor, the neutrophils develop a reactive phenotype with extensive priming features. PMID:23964611

Valsartan attenuates cardiac and renal hypertrophy in rats with experimental cardiorenal syndrome possibly through down-regulating galectin-3 signaling.

PubMed

Zhang, M-J; Gu, Y; Wang, H; Zhu, P-F; Liu, X-Y; Wu, J

2016-01-01

Aortocaval fistula (AV) induced chronic volume overload in rats with preexisting mild renal dysfunction (right kidney remove: UNX) could mimic the type 4 cardiorenal syndrome (CRS): chronic renocardiac syndrome. Galectin-3, a β-galactoside binding lectin, is an emerging biomarker in cardiovascular as well as renal diseases. We observed the impact of valsartan on cardiac and renal hypertrophy and galectin-3 changes in this model. Adult male Sprague-Dawley (SD) rats (200-250 g) were divided into S (Sham, n = 7), M (UNX+AV, n = 7) and M+V (UNX+AV+valsartan, n = 7) groups. Eight weeks later, cardiac function was measured by echocardiography. Renal outcome was measured by glomerular filtration rate, effective renal plasma flow, renal blood flow and 24 hours albuminuria. Immunohistochemistry and real-time PCR were used to evaluate the expressions of galectin-3 in heart and renal. Cardiac hypertrophy and renal hypertrophy as well as cardiac enlargement were evidenced in this AV shunt induced chronic volume overload rat model with preexisting mild renal dysfunction. Cardiac and renal hypertrophy were significantly attenuated but cardiac enlargement was unaffected by valsartan independent of its blood pressure lowering effect. 24 hours urine albumin was significantly increased, which was significantly reduced by valsartan in this model. Immunohistochemistry and real-time PCR evidenced significantly up-regulated galectin-3 expression in heart and kidney and borderline increased myocardial collagen I expression, which tended to be lower post valsartan treatment. Up-regulated galectin-3 signaling might also be involved in the pathogenesis in this CRS model. The beneficial effects of valsartan in terms of attenuating cardiac and renal hypertrophy and reducing 24 hours albumin in this model might partly be mediated through down-regulating galectin-3 signal pathway.

Galectin-9 Produced by Intestinal Epithelial Cells Enhances Aldehyde Dehydrogenase Activity in Dendritic Cells in a PI3K- and p38-Dependent Manner.

PubMed

de Kivit, Sander; Kostadinova, Atanaska I; Kerperien, JoAnn; Ayechu Muruzabal, Veronica; Morgan, Mary E; Knippels, Leon M J; Kraneveld, Aletta D; Garssen, Johan; Willemsen, Linette E M

2017-01-01

Intestinal epithelial cells (IEC) drive regulatory T cell (Treg) responses by promoting the differentiation of aldehyde dehydrogenase (ALDH)-expressing CD103+ dendritic cells (DC). Apical stimulation of TLR9 by CpG DNA on IEC supports galectin-9 expression by IEC, which is promoted by short-chain galacto-oligosaccharides and long-chain fructo-oligosaccharides (GF). While galectin-9 can induce the maturation of monocyte-derived DC (moDC), the contribution of galectin-9 on the induction of ALDH activity in DC is not known. To this end, DC were stimulated with galectin-9, and ALDH activity and the expression of CD103 were assessed. ALDH activity was increased by moDC exposed to galectin-9, while the expression of CD103 remained unaltered. Galectin-9 secreted by IEC apically exposed to CpG DNA and GF enhanced ALDH activity, but not CD103 expression by moDC, which was abrogated upon galectin-9 neutralization. Similar observations were found in murine GM-CSF-cultured bone marrow-derived DC (BMDC). Using Flt3L-cultured BMDC and ex vivo murine splenic DC, it was observed that galectin-9 only enhanced ALDH activity in the presence of GM-CSF in CD103- cells. The induction of ALDH activity in BMDC was dependent on p38 and PI3K signaling. These data indicate a novel role for galectin-9 in modulating innate immunity by inducing ALDH activity in DC. © 2017 S. Karger AG, Basel.

Galectin-3 modulates the polarized surface delivery of β1-integrin in epithelial cells.

PubMed

Hönig, Ellena; Ringer, Karina; Dewes, Jenny; von Mach, Tobias; Kamm, Natalia; Kreitzer, Geri; Jacob, Ralf

2018-05-10

Epithelial cells require a precise intracellular transport and sorting machinery in order to establish and maintain their polarized architecture. This machinery includes beta-galactoside binding galectins for glycoprotein targeting to the apical membrane. Galectin-3 sorts cargo destined for the apical plasma membrane into vesicular carriers. After delivery of cargo to the apical milieu, galectin-3 recycles back into sorting organelles. We analyzed the role of galectin-3 in the polarized distribution of β1-integrin in MDCK cells. Integrins are located primarily at the basolateral domain of epithelial cells. We demonstrate that a minor pool of β1-integrin interacts with galectin-3 at the apical plasma membrane. Knockdown of galectin-3 decreases apical delivery of β1-integrin. This loss is restored by supplementation with recombinant galectin-3 and galectin-3 overexpression. Our data suggest that galectin-3 targets newly synthesized β1-integrin to the apical membrane and promotes apical delivery of β1-integrin internalized from the basolateral membrane. In parallel, galectin-3 knockout results in a reduction in cell proliferation and an impairment in proper cyst development. Our results suggest that galectin-3 modulates the surface distribution of β1-integrin and affects the morphogenesis of polarized cells. © 2018. Published by The Company of Biologists Ltd.

The Many Roles of Galectin-3, a Multifaceted Molecule, in Innate Immune Responses against Pathogens

PubMed Central

Díaz-Alvarez, Laura

2017-01-01

Galectins are a group of evolutionarily conserved proteins with the ability to bind β-galactosides through characteristic carbohydrate-recognition domains (CRD). Galectin-3 is structurally unique among all galectins as it contains a C-terminal CRD linked to an N-terminal protein-binding domain, being the only chimeric galectin. Galectin-3 participates in many functions, both intra- and extracellularly. Among them, a prominent role for Galectin-3 in inflammation has been recognized. Galectin-3 has also been shown to directly bind to pathogens and to have various effects on the functions of the cells of the innate immune system. Thanks to these two properties, Galectin-3 participates in several ways in the innate immune response against invading pathogens. Galectin-3 has been proposed to function not only as a pattern-recognition receptor (PRR) but also as a danger-associated molecular pattern (DAMP). In this review, we analyze the various roles that have been assigned to Galectin-3, both as a PRR and as a DAMP, in the context of immune responses against pathogenic microorganisms. PMID:28607536

Galectin-3: a new biomarker for the diagnosis, analysis and prognosis of acute and chronic heart failure.

PubMed

Hrynchyshyn, Nataliya; Jourdain, Patrick; Desnos, Michel; Diebold, Benoit; Funck, François

2013-10-01

Heart failure constitutes an important medical, social and economic problem. The prevalence of heart failure is estimated as 2-3% of the adult population and increases with age, despite the scientific progress of the past decade, especially the emergence of natriuretic peptides, which have been widely used as reliable markers for diagnostic and prognostic evaluation. Identification of new reliable markers for diagnosis, analysis, prognosis of mortality and prevention of hospitalization is still necessary. Galectin-3 is a soluble β-galactoside-binding protein secreted by activated macrophages. Its main action is to bind to and activate the fibroblasts that form collagen and scar tissue, leading to progressive cardiac fibrosis. Numerous experimental studies have shown the important role of galectin-3 in cardiac remodelling due to fibrosis, independent of the fibrosis aetiology. Galectin-3 is significantly increased in chronic heart failure (acute or non-acute onset), independent of aetiology. Some clinical studies have confirmed the predictive value of galectin-3 in all-cause mortality in patients with heart failure. In our review, we aim to analyse the role of galectin-3 in the development of heart failure, its value in screening and clinical decision making and its possible predictive application in follow-up as a "routine" test in an addition to established biomarkers, such as B-type natriuretic peptide and N-terminal prohormone of B-type natriuretic peptide. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Differential expression of galectin-1 and galectin-3 in thyroid tumors. Potential diagnostic implications.

PubMed Central

Xu, X. C.; el-Naggar, A. K.; Lotan, R.

1995-01-01

Carcinoma of the thyroid gland, the most frequently diagnosed endocrine malignancy, is often associated with early regional metastases. With the exception of papillary carcinoma, distinguishing benign from malignant thyroid neoplasms in the absence of metastatic disease is difficult. Recently, the vertebrate lectins galectin-1 and galectin-3 have been implicated in the regulation of cellular growth, differentiation, and malignant transformation of a variety of tissues. To determine whether these galectins have a role in thyroid neoplasia, we analyzed 32 specimens from thyroid malignancies (16 papillary, 7 follicular, 8 medullary carcinomas, and 1 metastasis to lymph node), 10 benign thyroid adenomas, 1 nodular goiter, and 33 specimens from adjacent normal thyroid tissue for the expression of galectin-1 and galectin-3 with immunohistochemical and immunoblotting techniques utilizing anti-galectin antibodies. All thyroid malignancies of epithelial origin (ie, papillary and follicular carcinomas) and a metastatic lymph node from a papillary carcinoma expressed high levels of both galectin-1 and galectin-3. The medullary thyroid carcinomas, which are of parafollicular C cell origin, showed a weaker and variable expression of these galectins. In contrast, neither benign thyroid adenomas nor adjacent normal thyroid tissue expressed galectin-1 or galectin-3. These results suggest that galectin-1 and galectin-3 may be associated with malignant transformation of thyroid epithelium and may potentially serve as markers for distinguishing benign thyroid adenomas from differentiated thyroid carcinomas. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7677193

Tissue- and cell-specific localization of galectins, β-galactose-binding animal lectins, and their potential functions in health and disease.

PubMed

Nio-Kobayashi, Junko

2017-01-01

Fifteen galectins, β-galactose-binding animal lectins, are known to be distributed throughout the body. We herein summarize current knowledge on the tissue- and cell-specific localization of galectins and their potential functions in health and disease. Galectin-3 is widely distributed in epithelia, including the simple columnar epithelium in the gut, stratified squamous epithelium in the gut and skin, and transitional epithelium and several regions in nephrons in the urinary tract. Galectin-2 and galectin-4/6 are gut-specific, while galectin-7 is found in the stratified squamous epithelium in the gut and skin. The reproductive tract mainly contains galectin-1 and galectin-3, and their expression markedly changes during the estrous/menstrual cycle. The galectin subtype expressed in the corpus luteum (CL) changes in association with luteal function. The CL of women and cows displays a "galectin switch" with coordinated changes in the major galectin subtype and its ligand glycoconjugate structure. Macrophages express galectin-3, which may be involved in phagocytotic activity. Lymphoid tissues contain galectin-3-positive macrophages, which are not always stained with the macrophage marker, F4/80. Subsets of neurons in the brain and dorsal root ganglion express galectin-1 and galectin-3, which may contribute to the regeneration of damaged axons, stem cell differentiation, and pain control. The subtype-specific contribution of galectins to implantation, fibrosis, and diabetes are also discussed. The function of galectins may differ depending on the tissues or cells in which they act. The ligand glycoconjugate structures mediated by glycosyltransferases including MGAT5, ST6GAL1, and C2GnT are important for revealing the functions of galectins in healthy and disease states.

Galectin-3 Mediates Tumor Cell-Stroma Interactions by Activating Pancreatic Stellate Cells to Produce Cytokines via Integrin Signaling.

PubMed

Zhao, Wei; Ajani, Jaffer A; Sushovan, Guha; Ochi, Nobuo; Hwang, Rosa; Hafley, Margarete; Johnson, Randy L; Bresalier, Robert S; Logsdon, Craig D; Zhang, Zhiqian; Song, Shumei

2018-04-01

Pancreatic ductal adenocarcinoma (PDAC) is characterized by activated pancreatic stellate cells (PSCs), abundance of extracellular matrix (ECM), and production of cytokines and chemokines. Galectin 3 (GAL3), a β-galactoside-specific lectin, contributes to PDAC development but its effects on the stroma and cytokine production are unclear. The effect of recombinant human GAL3 (rGAL3) on activation of PSCs, production of cytokines, and ECM proteins was determined by proliferation, invasion, cytokine array, and quantitative polymerase chain reaction. We assessed co-cultures of PDAC cells with GAL3 genetic alterations with PSCs. Production of interleukin 8 (IL8) and activities of nuclear factor (NF)-κB were determined by enzyme-linked immunosorbent assay and luciferase reporter analyses. We studied the effects of inhibitors of NF-κB and integrin-linked kinase (ILK) on pathways activated by rGAL3. In analyses of the Gene Expression Omnibus database and our dataset, we observed higher levels of GAL3, IL8, and other cytokines in PDAC than in nontumor tissues. Production of IL8, granulocyte-macrophage colony-stimulating factor, chemokine ligand 1, and C-C motif chemokine ligand 2 increased in PSCs exposed to rGAL3 compared with controls. Culture of PSCs with PDAC cells that express different levels of GAL3 resulted in proliferation and invasion of PSCs that increased with level of GAL3. GAL3 stimulated transcription of IL8 through integrin subunit beta 1 (ITGB1) on PSCs, which activates NF-κB through ILK. Inhibitors of ILK or NF-κB or a neutralizing antibody against ITGB1 blocked transcription and production of IL8 from PSCs induced by rGAL3. The GAL3 inhibitor significantly reduced growth and metastases of orthotopic tumors that formed from PDAC and PSC cells co-implanted in mice. GAL3 activates PSC cells to produce inflammatory cytokines via ITGB1signaling to ILK and activation of NF-κB. Inhibition of this pathway reduced growth and metastases of pancreatic orthotopic tumors in mice. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Activated Microglia Desialylate and Phagocytose Cells via Neuraminidase, Galectin-3, and Mer Tyrosine Kinase

PubMed Central

Nomura, Koji; Vilalta, Anna; Allendorf, David H.; Hornik, Tamara C.

2017-01-01

Activated microglia can phagocytose dying, stressed, or excess neurons and synapses via the phagocytic receptor Mer tyrosine kinase (MerTK). Galectin-3 (Gal-3) can cross-link surface glycoproteins by binding galactose residues that are normally hidden below terminal sialic acid residues. Gal-3 was recently reported to opsonize cells via activating MerTK. We found that LPS-activated BV-2 microglia rapidly released Gal-3, which was blocked by calcineurin inhibitors. Gal-3 bound to MerTK on microglia and to stressed PC12 (neuron-like) cells, and it increased microglial phagocytosis of PC12 cells or primary neurons, which was blocked by inhibition of MerTK. LPS-activated microglia exhibited a sialidase activity that desialylated PC12 cells and could be inhibited by Tamiflu, a neuraminidase (sialidase) inhibitor. Sialidase treatment of PC12 cells enabled Gal-3 to bind and opsonize the live cells for phagocytosis by microglia. LPS-induced microglial phagocytosis of PC12 was prevented by small interfering RNA knockdown of Gal-3 in microglia, lactose inhibition of Gal-3 binding, inhibition of neuraminidase with Tamiflu, or inhibition of MerTK by UNC569. LPS-induced phagocytosis of primary neurons by primary microglia was also blocked by inhibition of MerTK. We conclude that activated microglia release Gal-3 and a neuraminidase that desialylates microglial and PC12 surfaces, enabling Gal-3 binding to PC12 cells and their phagocytosis via MerTK. Thus, Gal-3 acts as an opsonin of desialylated surfaces, and inflammatory loss of neurons or synapses may potentially be blocked by inhibiting neuraminidases, Gal-3, or MerTK. PMID:28500071

Lack of galectin-3 up-regulates IgA expression by peritoneal B1 lymphocytes during B cell differentiation.

PubMed

Oliveira, Felipe L; Bernardes, Emerson S; Brand, Camila; dos Santos, Sofia N; Cabanel, Mariana P; Arcanjo, Kátia D; Brito, José M; Borojevic, Radovan; Chammas, Roger; El-Cheikh, Márcia C

2016-02-01

Galectin-3 is a β-galactoside-binding protein with an inhibitory role in B cell differentiation into plasma cells in distinct lymphoid tissues. We use a model of chronic schistosomiasis, a well-characterized experimental disease hallmarked by polyclonal B cell activation, in order to investigate the role of galectin-3 in controlling IgA production through peritoneal B1 cells. Chronically infected, galectin-3-deficient mice (Lgals3(-/-)) display peritoneal fluid hypercellularity, increased numbers of atypical peritoneal IgM(+)/IgA(+) B1a and B1b lymphocytes and histological disturbances in plasma cell niches when compared with Lgals3(+/+) mice. Similar to our infection model, peritoneal B1 cells from uninfected Lgals3(-/-) mice show enhanced switching to IgA after in vitro treatment with interleukin-5 plus transforming growth factor-β (IL-5 + TGF-β1). A higher number of IgA(+) B1a lymphocytes was found in the peritoneal cavity of Lgals3(-/-)-uninfected mice at 1 week after i.p. injection of IL-5 + TGF-β1; this correlates with the increased levels of secreted IgA detected in the peritoneal fluid of these mice after cytokine treatment. Interestingly, a higher number of degranulated mast cells is present in the peritoneal cavity of uninfected and Schistosoma mansoni-infected Lgals3(-/-) mice, indicating that, at least in part, mast cells account for the enhanced differentiation of B1 into IgA-producing B cells found in the absence of galectin-3. Thus, a novel role is revealed for galectin-3 in controlling the expression of surface IgA by peritoneal B1 lymphocytes; this might have important implications for manipulating the mucosal immune response.

Serum galectin-3, but not galectin-1, levels are elevated in schizophrenia: implications for the role of inflammation.

PubMed

Kajitani, Kosuke; Yanagimoto, Kazuyuki; Nakabeppu, Yusaku

2017-10-01

Previous studies have reported that galectin-3 is involved in inflammatory processes in the central nervous system and that neuroinflammation may play a role in the pathogenesis of schizophrenia. However, the link between schizophrenia and various galectins is unclear. The objective of the present study is to determine whether galectin, a well-known lectin protein that binds to μ-galactoside, is associated with chronic schizophrenia. Thirty-six patients with schizophrenia and 36 healthy controls participated in this study. Schizophrenia symptoms were assessed using the Brief Psychiatry Rating Scale (BPRS). Serum galectin-1 and galectin-3 levels were evaluated using ELISA and compared between the participant groups. Correlation analyses were also performed to examine the relationship between BPRS scores and each galectin level. Serum galectin-3 levels were significantly higher in patients with schizophrenia than they were in controls (p = 0.009, d = 0.640); however, serum galectin-1 levels were not significantly different between the groups (p = 0.513). No significant correlation was identified between serum galectin-3 level and the total BPRS score; however, a significant positive correlation was found between the serum galectin-3 level and the positive symptom score of the BPRS (ρ = 0.355; p = 0.033). Additionally, a significant negative correlation was identified between serum galectin-3 levels and the negative symptom score of the BPRS (ρ = -0.387; p = 0.020). Given the high serum levels of galectin-3 found in patients with schizophrenia compared with that in controls, these findings may support the inflammation hypothesis of schizophrenia.

Binding of galectin-1 to integrin β1 potentiates drug resistance by promoting survivin expression in breast cancer cells.

PubMed

Nam, KeeSoo; Son, Seog-Ho; Oh, Sunhwa; Jeon, Donghwan; Kim, Hyungjoo; Noh, Dong-Young; Kim, Sangmin; Shin, Incheol

2017-05-30

Galectin-1 is a β-galactoside binding protein secreted by many types of aggressive cancer cells. Although many studies have focused on the role of galectin-1 in cancer progression, relatively little attention has been paid to galectin-1 as an extracellular therapeutic target. To elucidate the molecular mechanisms underlying galectin-1-mediated cancer progression, we established galectin-1 knock-down cells via retroviral delivery of short hairpin RNA (shRNA) against galectin-1 in two triple-negative breast cancer (TNBC) cell lines, MDA-MB-231 and Hs578T. Ablation of galectin-1 expression decreased cell proliferation, migration, invasion, and doxorubicin resistance. We found that these effects were caused by decreased galectin-1-integrin β1 interactions and suppression of the downstream focal adhesion kinase (FAK)/c-Src pathway. We also found that silencing of galectin-1 inhibited extracellular signal-regulated kinase (ERK)/signal transducer and activator of transcription 3 (STAT3) signaling, thereby down-regulating survivin expression. This finding implicates STAT3 as a transcription factor for survivin. Finally, rescue of endogenous galectin-1 knock-down and recombinant galectin-1 treatment both recovered signaling through the FAK/c-Src/ERK/STAT3/survivin pathway. Taken together, these results suggest that extracellular galectin-1 contributes to cancer progression and doxorubicin resistance in TNBC cells. These effects appear to be mediated by galectin-1-induced up-regulation of the integrin β1/FAK/c-Src/ERK/STAT3/survivin pathway. Our results imply that extracellular galectin-1 has potential as a therapeutic target for triple-negative breast cancer.

Human Galectin-9 Is a Potent Mediator of HIV Transcription and Reactivation

PubMed Central

Abdel-Mohsen, Mohamed; Chavez, Leonard; Tandon, Ravi; Chew, Glen M.; Deng, Xutao; Danesh, Ali; Keating, Sheila; Lanteri, Marion; Samuels, Michael L.; Hoh, Rebecca; Sacha, Jonah B.; Norris, Philip J.; Niki, Toshiro; Shikuma, Cecilia M.; Hirashima, Mitsuomi; Deeks, Steven G.; Ndhlovu, Lishomwa C.; Pillai, Satish K.

2016-01-01

Identifying host immune determinants governing HIV transcription, latency and infectivity in vivo is critical to developing an HIV cure. Based on our recent finding that the host factor p21 regulates HIV transcription during antiretroviral therapy (ART), and published data demonstrating that the human carbohydrate-binding immunomodulatory protein galectin-9 regulates p21, we hypothesized that galectin-9 modulates HIV transcription. We report that the administration of a recombinant, stable form of galectin-9 (rGal-9) potently reverses HIV latency in vitro in the J-Lat HIV latency model. Furthermore, rGal-9 reverses HIV latency ex vivo in primary CD4+ T cells from HIV-infected, ART-suppressed individuals (p = 0.002), more potently than vorinostat (p = 0.02). rGal-9 co-administration with the latency reversal agent "JQ1", a bromodomain inhibitor, exhibits synergistic activity (p<0.05). rGal-9 signals through N-linked oligosaccharides and O-linked hexasaccharides on the T cell surface, modulating the gene expression levels of key transcription initiation, promoter proximal-pausing, and chromatin remodeling factors that regulate HIV latency. Beyond latent viral reactivation, rGal-9 induces robust expression of the host antiviral deaminase APOBEC3G in vitro and ex vivo (FDR<0.006) and significantly reduces infectivity of progeny virus, decreasing the probability that the HIV reservoir will be replenished when latency is reversed therapeutically. Lastly, endogenous levels of soluble galectin-9 in the plasma of 72 HIV-infected ART-suppressed individuals were associated with levels of HIV RNA in CD4+ T cells (p<0.02) and with the quantity and binding avidity of circulating anti-HIV antibodies (p<0.009), suggesting a role of galectin-9 in regulating HIV transcription and viral production in vivo during therapy. Our data suggest that galectin-9 and the host glycosylation machinery should be explored as foundations for novel HIV cure strategies. PMID:27253379

[Galectin-3 in Patients With Paroxysmal and Persistent Atrial Fibrillation and Metabolic Syndrome].

PubMed

A, V A; Zaslavskaya, E L; Soboleva, A V; Baranova, E I; Listopad, O V; Nifontov, S E; Nrady, A O; Shlyakhto, E V

2016-06-01

To evaluate serum galectin 3 and to determine the potential clinical value of this parameter in patients with atrial fibrillation - AF (paroxysmal and persistent) and metabolic syndrome (MS). We examined 100 patients with MS (50 with paroxysmal or persistent AF and 50 without arrhythmia) and 50 healthy persons. Serum galectin 3 measured by ELISA method, ECHO cardiography was performed to all examined persons. Galectin 3 in patients with MS and AF was higher, than in patients with MS without arrhythmia and much more higher than galectin 3 in healthy persons 0,72 (0,44;1,36), 0,44 (0,42;1,22) and 0,32 (0,28;0,42) ng/ml (<0,01). In patients with persistent AF levels of galectin 3 is higher than in patients with paroxysmal AF. Positive correlation between the levels of galectin 3 and duration arrhythmia was revealed (r=0,301; p<0,01). Higher level of galectin 3 was revealed in patients with frequent paroxysms of AF and ineffective antiarrhythmic therapy. Marker of myocardial fibrosis serum galectin 3 in patients with atrial fibrillation and metabolic syndrome is higher than in patients with the metabolic syndrome, without this arrhythmia and higher than in healthy controls. In patients with persistent AF level of galectin 3 was higher than in patients with paroxysmal AF.

Serum galectin-1 levels are positively correlated with body fat and negatively with fasting glucose in obese children.

PubMed

Acar, Sezer; Paketçi, Ahu; Küme, Tuncay; Tuhan, Hale; Gürsoy Çalan, Özlem; Demir, Korcan; Böber, Ece; Abacı, Ayhan

2017-09-01

Galectin-1, a recently identified peptide, is primarily released from the adipose tissue. Although galectin-1 was shown to have an anti-inflammatory effect, its specific function is not clearly understood. We aimed to evaluate the relationship of serum galectin-1 levels with clinical and laboratory parameters in childhood obesity. A total of 45 obese children (mean age: 12.1±3.1years) and 35 normal-weight children (mean age: 11.8±2.2years) were enrolled. Clinical [body mass index (BMI), waist circumference (WC), percentage of body fat and blood pressure] and biochemical [glucose, insulin, lipids, galectin-1, high-sensitive C-reactive protein (hsCRP) and leptin levels] parameters were assessed. Serum galectin-1, hsCRP and leptin levels were significantly higher in obese children than those in normal-weight children (12.4 vs 10.2ng/mL, p<0.001; 3.28 vs 0.63mg/L, p<0.001; 8.3 vs 1.2ng/mL, p<0.001, respectively). In obese children, galectin-1 levels correlated negatively with fasting glucose (r=-0.346, p=0.020) and positively with fat mass (r=0.326, p=0.026) and WC standard deviation score (SDS) (r=0.451, p=0.002). The multivariate regression analysis demonstrated that serum galectin-1 levels were significantly associated with fasting glucose and WC SDS. This study showed that obese children had significantly higher galectin-1 levels in proportion to fat mass in obese cases than those in healthy children, which may be interpreted as a compensatory increase in an attempt to improve glucose metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

CD206-positive myeloid cells bind galectin-9 and promote a tumor-supportive microenvironment.

PubMed

Enninga, Elizabeth Ann L; Chatzopoulos, Kyriakos; Butterfield, John T; Sutor, Shari L; Leontovich, Alexey A; Nevala, Wendy K; Flotte, Thomas J; Markovic, Svetomir N

2018-05-07

In patients with metastatic melanoma, high blood levels of galectin-9 are correlated with worse overall survival and a bias towards a Th2 inflammatory state supportive of tumor growth. Although galectin-9 signaling through TIM3 on T cells has been described, less is known about the interaction of galectin-9 with macrophages. We aimed to determine whether galectin-9 is a binding partner of CD206 on macrophages and whether the result of this interaction is tumor-supportive. It was determined that incubation of CD68+ macrophages with galectin-9 or anti-CD206 blocked target binding and that both CD206 and galectin-9 were detected by immunoprecipitation of cell lysates. CD206 and galectin-9 had a binding affinity of 2.8 × 10 -7 M. Galectin-9 causes CD206+ macrophages to make significantly more FGF2 and monocyte chemoattractant protein (MCP-1), but less macrophage-derived chemokine (MDC). Galectin-9 had no effect on classical monocyte subsets, but caused expansion of the non-classical populations. Lastly, there was a positive correlation between increasing numbers of CD206 macrophages and galectin-9 expression in tumors, and high levels of CD206 macrophages correlated negatively with melanoma survival. These results indicate that galectin-9 binds CD206 on M2 macrophages, which appear to drive angiogenesis and the production of chemokines that support tumor growth and poor patient prognoses. Targeting this interaction systemically through circulating monocytes may therefore be a novel way to improve local anti-tumor effects by macrophages. This article is protected by copyright. All rights reserved.

Galectin-3 Inhibition Is Associated with Neuropathic Pain Attenuation after Peripheral Nerve Injury

PubMed Central

Ai, Zisheng; Zheng, Yongjun

2016-01-01

Neuropathic pain remains a prevalent and persistent clinical problem because it is often poorly responsive to the currently used analgesics. It is very urgent to develop novel drugs to alleviate neuropathic pain. Galectin-3 (gal3) is a multifunctional protein belonging to the carbohydrate-ligand lectin family, which is expressed by different cells. Emerging studies showed that gal3 elicits a pro-inflammatory response by recruiting and activating lymphocytes, macrophages and microglia. In the study we investigated whether gal3 inhibition could suppress neuroinflammation and alleviate neuropathic pain following peripheral nerve injury. We found that L5 spinal nerve ligation (SNL) increases the expression of gal3 in dorsal root ganglions at the mRNA and protein level. Intrathecal administration of modified citrus pectin (MCP), a gal3 inhibitor, reduces gal3 expression in dorsal root ganglions. MCP treatment also inhibits SNL-induced gal3 expression in primary rat microglia. SNL results in an increased activation of autophagy that contributes to microglial activation and subsequent inflammatory response. Intrathecal administration of MCP significantly suppresses SNL-induced autophagy activation. MCP also inhibits lipopolysaccharide (LPS)-induced autophagy in cultured microglia in vitro. MCP further decreases LPS-induced expression of proinflammatory mediators including IL-1β, TNF-α and IL-6 by regulating autophagy. Intrathecal administration of MCP results in adecreased mechanical and cold hypersensitivity following SNL. These results demonstrated that gal3 inhibition is associated with the suppression of SNL-induced inflammatory process andneurophathic pain attenuation. PMID:26872020

Bisected, complex N-glycans and galectins in mouse mammary tumor progression and human breast cancer

PubMed Central

Miwa, Hazuki E; Koba, Wade R; Fine, Eugene J; Giricz, Orsi; Kenny, Paraic A; Stanley, Pamela

2013-01-01

Bisected, complex N-glycans on glycoproteins are generated by the glycosyltransferase MGAT3 and cause reduced cell surface binding of galectins. Previously, we showed that MGAT3 reduces growth factor signaling and retards mammary tumor progression driven by the Polyoma middle T antigen (PyMT) expressed in mammary epithelium under the mouse mammary tumor virus (MMTV) promoter. However, the penetrance of the tumor phenotype became variable in mixed FVB/N and C57BL/6 female mice and we therefore investigated a congenic C57BL/6 Mgat3−/−/MMTV-PyMT model. In the absence of MGAT3, C57BL/6 Mgat3−/−/MMTV-PyMT females exhibited accelerated tumor appearance and increased tumor burden, glucose uptake in tumors and lung metastasis. Nevertheless, activation of extracellular signal-regulated kinase (ERK)1/2 or protein kinase B (AKT) was reduced in ∼20-week C57BL/6 MMTV-PyMT tumors lacking MGAT3. Activation of focal adhesion kinase (FAK), protein tyrosine kinase Src, and p38 mitogen-activated protein kinase were similar to that of controls. All the eight mouse galectin genes were expressed in mammary tumors and tumor epithelial cells (TECs), but galectin-2 and -12 were not detected by western analysis in tumors, and galectin-7 was not detected in 60% of the TEC lines. From microarray data reported for human breast cancers, at least 10 galectin and 7 N-glycan N-acetylglucosaminyl (GlcNAc)-transferase (MGAT) genes are expressed in tumor tissue, and expression often varies significantly between different breast cancer subtypes. Thus, in summary, while MGAT3 and bisected complex N-glycans retard mouse mammary tumor progression, genetic background may modify this effect; identification of key galectins that promote mammary tumor progression in mice is not straightforward because all the eight galectin genes are expressed; and high levels of MGAT3, galectin-4, -8, -10, -13 and -14 transcripts correlate with better relapse-free survival in human breast cancer. PMID:24037315

Galectin-3 in Heart Failure: An Update of the Last 3 Years.

PubMed

Gehlken, Carolin; Suthahar, Navin; Meijers, Wouter C; de Boer, Rudolf A

2018-01-01

Galectin-3 plays a role in tissue inflammation, repair, and fibrosis. This article specifically focuses on heart failure (HF), in which galectin-3 has been shown to be a useful biomarker in prognosis and risk stratification, especially in HF with preserved ejection fraction. Experimental research has shown that galectin-3 directly induces pathologic remodeling of the heart, and is therefore considered a culprit protein in the development of cardiac fibrosis in HF, with potentially relevant clinical implications. In summary, galectin-3 is a biomarker and biotarget in cardiac remodeling and fibrosis and future research will target galectin-3-centered diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Krüppel-like Factor 3 (KLF3/BKLF) Is Required for Widespread Repression of the Inflammatory Modulator Galectin-3 (Lgals3)*

PubMed Central

Knights, Alexander J.; Yik, Jinfen J.; Mat Jusoh, Hanapi; Norton, Laura J.; Funnell, Alister P. W.; Pearson, Richard C. M.; Bell-Anderson, Kim S.; Crossley, Merlin; Quinlan, Kate G. R.

2016-01-01

The Lgals3 gene encodes a multifunctional β-galactoside-binding protein, galectin-3. Galectin-3 has been implicated in a broad range of biological processes from chemotaxis and inflammation to fibrosis and apoptosis. The role of galectin-3 as a modulator of inflammation has been studied intensively, and recent evidence suggests that it may serve as a protective factor in obesity and other metabolic disorders. Despite considerable interest in galectin-3, little is known about its physiological regulation at the transcriptional level. Here, using knockout mice, chromatin immunoprecipitations, and cellular and molecular analyses, we show that the zinc finger transcription factor Krüppel-like factor 3 (KLF3) directly represses galectin-3 transcription. We find that galectin-3 is broadly up-regulated in KLF3-deficient mouse tissues, that KLF3 occupies regulatory regions of the Lgals3 gene, and that KLF3 directly binds its cognate elements (CACCC boxes) in the galectin-3 promoter and represses its activation in cellular assays. We also provide mechanistic insights into the regulation of Lgals3, demonstrating that C-terminal binding protein (CtBP) is required to drive optimal KLF3-mediated silencing. These findings help to enhance our understanding of how expression of the inflammatory modulator galectin-3 is controlled, opening up avenues for potential therapeutic interventions in the future. PMID:27226561

Inhibition of Galectin-1 Sensitizes HRAS-driven Tumor Growth to Rapamycin Treatment.

PubMed

Michael, James V; Wurtzel, Jeremy G T; Goldfinger, Lawrence E

2016-10-01

The goal of this study was to develop combinatorial application of two drugs currently either in active use as anticancer agents (rapamycin) or in clinical trials (OTX008) as a novel strategy to inhibit Harvey RAS (HRAS)-driven tumor progression. HRAS anchored to the plasma membrane shuttles from the lipid ordered (L o ) domain to the lipid ordered/lipid disordered border upon activation, and retention of HRAS at these sites requires galectin-1. We recently showed that genetically enforced L o sequestration of HRAS inhibited mitogen-activated protein kinase (MAPK) signaling, but not phoshatidylinositol 3-kinase (PI3K) activation. Here we show that inhibition of galectin-1 with OTX008 sequestered HRAS in the L o domain, blocked HRAS-mediated MAPK signaling, and attenuated HRAS-driven tumor progression in mice. HRAS-driven tumor growth was also attenuated by treatment with mammalian target of rapamycin (mTOR) inhibitor rapamycin, and this effect was further enhanced in tumors driven by L o -sequestered HRAS. These drugs also revealed bidirectional cross-talk in HRAS pathways. Moreover, dual pathway inhibition with OTX008 and rapamycin resulted in nearly complete ablation of HRAS-driven tumor growth. These findings indicate that membrane microdomain sequestration of HRAS with galectin-1 inhibition, coupled with mTOR inhibition, may support a novel therapeutic approach to treat HRAS-mutant cancer. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Two birds, one stone: dual targeting of the cancer cell surface and subcellular mitochondria by the galectin-3-binding peptide G3-C12

PubMed Central

Sun, Wei; Li, Lian; Li, Li-jia; Yang, Qing-qing; Zhang, Zhi-rong; Huang, Yuan

2017-01-01

Active tumor-targeting approaches using specific ligands have drawn considerable attention over the years. However, a single ligand often fails to simultaneously target the cancer cell surface and subcellular organelles, which limits the maximum therapeutic efficacy of delivered drugs. We describe a polymeric delivery system modified with the G3-C12 peptide for sequential dual targeting. In this study, galectin-3-targeted G3-C12 peptide was conjugated onto the N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer for the delivery of D(KLAKLAK)2 (KLA) peptide. G3-C12-HPMA-KLA exhibited increased receptor-mediated internalization into galectin-3-overexpressing PC-3 cells. Furthermore, G3-C12 peptide also directed HPMA-KLA conjugates to mitochondria. This occurred because the apoptosis signal triggered the accumulation of galectin-3 in mitochondria, and the G3-C12 peptide that specifically bound to galectin-3 was trafficked along with its receptor intracellularly. As a result, G3-C12-HPMA-KLA disrupted the mitochondrial membrane, increased the generation of reactive oxygen species (ROS) and induced cytochrome c release, which ultimately resulted in enhanced cytotoxicity. An in vivo study revealed that the G3-C12 peptide significantly enhanced the tumor accumulation of the KLA conjugate. In addition, G3-C12-HPMA-KLA exhibited the best therapeutic efficacy and greatly improved the animal survival rate. Our work demonstrates that G3-C12 is a promising ligand with dual-targeting functionality. PMID:28065935

O-Glycosylation-mediated signaling circuit drives metastatic castration-resistant prostate cancer.

PubMed

Tzeng, Sheue-Fen; Tsai, Chin-Hsien; Chao, Tai-Kuang; Chou, Yu-Ching; Yang, Yu-Chih; Tsai, Mong-Hsun; Cha, Tai-Lung; Hsiao, Pei-Wen

2018-06-15

Disseminated castration-resistant prostate cancer (CRPC) is a common disease in men that is characterized by limited survival and resistance to androgen-deprivation therapy. The increase in human epidermal growth factor receptor 2 (HER2) signaling contributes to androgen receptor activity in a subset of patients with CRPC; however, enigmatically, HER2-targeted therapies have demonstrated a lack of efficacy in patients with CRPC. Aberrant glycosylation is a hallmark of cancer and involves key processes that support cancer progression. Using transcriptomic analysis of prostate cancer data sets, histopathologic examination of clinical specimens, and in vivo experiments of xenograft models, we reveal in this study a coordinated increase in glycan-binding protein, galectin-4, specific glycosyltransferases of core 1 synthase, glycoprotein- N-acetylgalactosamine 3-β-galactosyltransferase 1 (C1GALT1) and ST3 beta-galactoside α-2,3-sialyltransferase 1 (ST3GAL1), and resulting mucin-type O-glycans during the progression of CRPC. Furthermore, galectin-4 engaged with C1GALT1-dependent O-glycans to promote castration resistance and metastasis by activating receptor tyrosine kinase signaling and cancer cell stemness properties mediated by SRY-box 9 (SOX9). This galectin-glycan interaction up-regulated the MYC-dependent expression of C1GALT1 and ST3GAL1, which altered cellular mucin-type O-glycosylation to allow for galectin-4 binding. In clinical prostate cancer, high-level expression of C1GALT1 and galectin-4 together predict poor overall survival compared with low-level expression of C1GALT1 and galectin-4. In summary, MYC regulates abnormal O-glycosylation, thus priming cells for binding to galectin-4 and downstream signaling, which promotes castration resistance and metastasis.-Tzeng, S.-F., Tsai, C.-H., Chao, T.-K., Chou, Y.-C., Yang, Y.-C., Tsai, M.-H., Cha, T.-L., Hsiao, P.-W. O-Glycosylation-mediated signaling circuit drives metastatic castration-resistant prostate cancer.

Galectin-3 Binds to Lubricin and Reinforces the Lubricating Boundary Layer of Articular Cartilage.

PubMed

Reesink, Heidi L; Bonnevie, Edward D; Liu, Sherry; Shurer, Carolyn R; Hollander, Michael J; Bonassar, Lawrence J; Nixon, Alan J

2016-05-09

Lubricin is a mucinous, synovial fluid glycoprotein that enables near frictionless joint motion via adsorption to the surface of articular cartilage and its lubricating properties in solution. Extensive O-linked glycosylation within lubricin's mucin-rich domain is critical for its boundary lubricating function; however, it is unknown exactly how glycosylation facilitates cartilage lubrication. Here, we find that the lubricin glycome is enriched with terminal β-galactosides, known binding partners for a family of multivalent lectins called galectins. Of the galectin family members present in synovial fluid, we find that galectin-3 is a specific, high-affinity binding partner for lubricin. Considering the known ability of galectin-3 to crosslink glycoproteins, we hypothesized that galectins could augment lubrication via biomechanical stabilization of the lubricin boundary layer. We find that competitive inhibition of galectin binding results in lubricin loss from the cartilage surface, and addition of multimeric galectin-3 enhances cartilage lubrication. We also find that galectin-3 has low affinity for the surface layer of osteoarthritic cartilage and has reduced affinity for sialylated O-glycans, a glycophenotype associated with inflammatory conditions. Together, our results suggest that galectin-3 reinforces the lubricin boundary layer; which, in turn, enhances cartilage lubrication and may delay the onset and progression of arthritis.

Galectin-3 Binds to Lubricin and Reinforces the Lubricating Boundary Layer of Articular Cartilage

PubMed Central

Reesink, Heidi L.; Bonnevie, Edward D.; Liu, Sherry; Shurer, Carolyn R.; Hollander, Michael J.; Bonassar, Lawrence J.; Nixon, Alan J.

2016-01-01

Lubricin is a mucinous, synovial fluid glycoprotein that enables near frictionless joint motion via adsorption to the surface of articular cartilage and its lubricating properties in solution. Extensive O-linked glycosylation within lubricin’s mucin-rich domain is critical for its boundary lubricating function; however, it is unknown exactly how glycosylation facilitates cartilage lubrication. Here, we find that the lubricin glycome is enriched with terminal β-galactosides, known binding partners for a family of multivalent lectins called galectins. Of the galectin family members present in synovial fluid, we find that galectin-3 is a specific, high-affinity binding partner for lubricin. Considering the known ability of galectin-3 to crosslink glycoproteins, we hypothesized that galectins could augment lubrication via biomechanical stabilization of the lubricin boundary layer. We find that competitive inhibition of galectin binding results in lubricin loss from the cartilage surface, and addition of multimeric galectin-3 enhances cartilage lubrication. We also find that galectin-3 has low affinity for the surface layer of osteoarthritic cartilage and has reduced affinity for sialylated O-glycans, a glycophenotype associated with inflammatory conditions. Together, our results suggest that galectin-3 reinforces the lubricin boundary layer; which, in turn, enhances cartilage lubrication and may delay the onset and progression of arthritis. PMID:27157803

Galectin-3 Binds to Lubricin and Reinforces the Lubricating Boundary Layer of Articular Cartilage

NASA Astrophysics Data System (ADS)

Reesink, Heidi L.; Bonnevie, Edward D.; Liu, Sherry; Shurer, Carolyn R.; Hollander, Michael J.; Bonassar, Lawrence J.; Nixon, Alan J.

2016-05-01

Lubricin is a mucinous, synovial fluid glycoprotein that enables near frictionless joint motion via adsorption to the surface of articular cartilage and its lubricating properties in solution. Extensive O-linked glycosylation within lubricin’s mucin-rich domain is critical for its boundary lubricating function; however, it is unknown exactly how glycosylation facilitates cartilage lubrication. Here, we find that the lubricin glycome is enriched with terminal β-galactosides, known binding partners for a family of multivalent lectins called galectins. Of the galectin family members present in synovial fluid, we find that galectin-3 is a specific, high-affinity binding partner for lubricin. Considering the known ability of galectin-3 to crosslink glycoproteins, we hypothesized that galectins could augment lubrication via biomechanical stabilization of the lubricin boundary layer. We find that competitive inhibition of galectin binding results in lubricin loss from the cartilage surface, and addition of multimeric galectin-3 enhances cartilage lubrication. We also find that galectin-3 has low affinity for the surface layer of osteoarthritic cartilage and has reduced affinity for sialylated O-glycans, a glycophenotype associated with inflammatory conditions. Together, our results suggest that galectin-3 reinforces the lubricin boundary layer; which, in turn, enhances cartilage lubrication and may delay the onset and progression of arthritis.

Diagnostic value of TROP-2 expression in papillary thyroid carcinoma and comparison with HBME-1, galectin-3 and cytokeratin 19.

PubMed

Murtezaoglu, Afsin Rahman; Gucer, Hasan

In this study, we compared the diagnostic value of TROP-2 expression in distinguishing between benign and malignant thyroid lesions to those of HBME-1, CK19 and galectin-3. We selected 102 cases from our archive including 20 normal thyroid tissues, 23 follicular nodular diseases, 17 follicular adenomas, 20 follicular variant papillary carcinomas and 22 classical variant papillary carcinomas. Tissue microarrays constructed from these cases were immunohistochemically analyzed with HBME-1, CK19, galectin-3 and TROP-2. Respectively 73.8%, 83.3%, 69% and 50% of all papillary carcinomas were positive with HBME-1, CK19, galectin-3 and TROP-2. CK19 was positive respectively by 100%, 43.5% and 35.3% in cases of normal thyroid, follicular nodular diseases and follicular adenoma, while the other markers were negative. In distinguishing benign and malignant lesions, which constitutes this study, HBME-1, CK19, galectin-3 and TROP-2 were statistically significant (p < 0.001). In distinguishing cases of follicular variant papillary carcinoma from follicular nodular diseases and follicular adenoma, HBME-1 and galectin-3 were statistically significant (p < 0.001). Consequently, in this study, we found that all immunohistochemical markers were effective in distinguishing benign and malignant thyroid lesions. In determining malignancy, HBME-1 had the highest diagnostic accuracy, while CK19 was the most sensitive marker. The sensitivity increased when the markers were used together.

The growing galectin network in colon cancer and clinical relevance of cytoplasmic galectin-3 reactivity.

PubMed

Dawson, Heather; André, Sabine; Karamitopoulou, Eva; Zlobec, Inti; Gabius, Hans-Joachim

2013-08-01

Human lectins translate sugar-encoded signals of cell surface glycoconjugates into biological effects, and this is what is known for the adhesion/growth-regulatory galectins. In addition, the multifunctional members of this group can be intracellular, binding to distinct proteins. The presence of galectins and galectin reactivity were exemplarily studied in the present article. We combined immuno- and lectin histochemical monitoring in colon cancer on tissue arrays. Intracellular presence of galectins-7 and -9 in colon cancer is detected, extending the previously known set of five expressed lectins this tumor type. The assumed significance of intracellular galectin presence, e.g. for an interplay with BCL2, β-catenin, oncogenic KRAS or synexin, is underscored by respective staining with labeled galectin-3. Statistical significance was obtained for galectin-3 staining with respect to tumor differentiation (p=0.0376), lymph node metastasis (p=0.0069) and lymphatic invasion (p=0.0156). Survival was correlated to staining, galectin-3 reactivity indicating a favorable prognosis (p=0.0183), albeit not as an independent marker. No correlation to KRAS/BRAF status was detected. These results encourage further testing of labeled human galectins as probes and immunohistochemical fingerprinting instead of measuring single or few activities, in colon cancer and other tumor types.

Galectin-3 Activation and Inhibition in Heart Failure and Cardiovascular Disease: An Update.

PubMed

Suthahar, Navin; Meijers, Wouter C; Silljé, Herman H W; Ho, Jennifer E; Liu, Fu-Tong; de Boer, Rudolf A

2018-01-01

Galectin-3 is a versatile protein orchestrating several physiological and pathophysiological processes in the human body. In the last decade, considerable interest in galectin-3 has emerged because of its potential role as a biotarget. Galectin-3 is differentially expressed depending on the tissue type, however its expression can be induced under conditions of tissue injury or stress. Galectin-3 overexpression and secretion is associated with several diseases and is extensively studied in the context of fibrosis, heart failure, atherosclerosis and diabetes mellitus. Monomeric (extracellular) galectin-3 usually undergoes further "activation" which significantly broadens the spectrum of biological activity mainly by modifying its carbohydrate-binding properties. Self-interactions of this protein appear to play a crucial role in regulating the extracellular activities of this protein, however there is limited and controversial data on the mechanisms involved. We therefore summarize (recent) literature in this area and describe galectin-3 from a binding perspective providing novel insights into mechanisms by which galectin-3 is known to be "activated" and how such activation may be regulated in pathophysiological scenarios.

Galectin-3 Activation and Inhibition in Heart Failure and Cardiovascular Disease: An Update

PubMed Central

Suthahar, Navin; Meijers, Wouter C.; Silljé, Herman H.W.; Ho, Jennifer E.; Liu, Fu-Tong; de Boer, Rudolf A.

2018-01-01

Galectin-3 is a versatile protein orchestrating several physiological and pathophysiological processes in the human body. In the last decade, considerable interest in galectin-3 has emerged because of its potential role as a biotarget. Galectin-3 is differentially expressed depending on the tissue type, however its expression can be induced under conditions of tissue injury or stress. Galectin-3 overexpression and secretion is associated with several diseases and is extensively studied in the context of fibrosis, heart failure, atherosclerosis and diabetes mellitus. Monomeric (extracellular) galectin-3 usually undergoes further “activation” which significantly broadens the spectrum of biological activity mainly by modifying its carbohydrate-binding properties. Self-interactions of this protein appear to play a crucial role in regulating the extracellular activities of this protein, however there is limited and controversial data on the mechanisms involved. We therefore summarize (recent) literature in this area and describe galectin-3 from a binding perspective providing novel insights into mechanisms by which galectin-3 is known to be “activated” and how such activation may be regulated in pathophysiological scenarios. PMID:29344292

Seasonal and flight-related variation of galectin expression in heart, liver and flight muscles of yellow-rumped warblers (Setophaga coronata).

PubMed

Bradley, Stefanie S; Dick, Morag F; Guglielmo, Christopher G; Timoshenko, Alexander V

2017-10-01

Galectins, a family of multifunctional glycan-binding proteins, are proposed as biomarkers of cellular stress responses. Avian migration is an energetically challenging physical stress, which represents a physiological model of muscular endurance exercises. This study assesses change in galectin gene expression profiles associated with seasonal variation in migratory state and endurance flight in yellow-rumped warblers (Setophaga coronata). Bioinformatics analysis and real-time qPCR were used to analyse the expression of galectins in flight muscle, heart and liver tissues of 15 warblers separated into three groups of winter unflown, and fall migratory flown/unflown birds. Five transcripts similar to chicken and human galectins -1, -2, -3, -4, and -8 were identified in warbler tissues. The expression of these galectins showed no seasonal changes between two experimental groups of birds maintained under unflown winter and fall conditions indicating a minor role of galectins in preparation for migration. However, endurance flight led to a significant elevation of galectin-1 and galectin-3 mRNAs in flight muscles and galectin-3 mRNA in heart tissue while no changes were observed in liver. Different changes were observed for the level of O-GlcNAcylated proteins, which were elevated in flight muscles under winter conditions. These results suggest that secreted galectin-1 and galectin-3 may be active in repair of bird muscles during and following migratory flight and serve as molecular biomarkers of recent arrival from migratory flights in field studies.

Galectin-3 expression in response to LPS, immunomodulatory drugs and exogenously added galectin-3 in monocyte-like THP-1 cells.

PubMed

Dabelic, Sanja; Novak, Ruder; Goreta, Sandra Supraha; Dumic, Jerka

2012-09-01

Galectin-3, a structurally unique beta-galactoside-binding lectin, through the specific protein-protein and protein-carbohydrate interactions participates in numerous biological processes, such as cell proliferation and apoptosis, adhesion and activation. Its expression and secretion by until now an unknown mechanism are modulated by diverse molecules and are dependent on different physiological and pathophysiological conditions. By autocrine and paracrine actions, galectin-3 modulates many immune reactions and affects various immune cells, particularly those of monocyte-macrophage lineage. This is why galectin-3 has recently become an attractive therapeutic target. However, molecular mechanisms of its actions as well as regulatory mechanism of its expression and activation are still largely unknown. In this study, we show that lipopolysaccharide (LPS) provokes upregulation of galectin-3 expression on both gene and protein level in monocyte-like THP-1 cells, which can be inhibited by dexamethasone, but not with non-steroidal anti-inflammatory drugs aspirin and indomethacin. Resting and LPS-challenged monocyte-like THP-1 cells do not have detectable amount of surface-bound galectin-3, but are able to bind exogenously added galectin-3 with the same capacity. Although galectin-3 is generally considered to be a pro-inflammatory molecule, here we show that the exogenously added galectin-3 does not affect interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12p70 and TNF-α production in resting and LPS-activated monocyte-like THP-1 cells nor influences its own gene expression level in those cells.

Methodology and technical requirements of the galectin-3 test for the preoperative characterization of thyroid nodules.

PubMed

Bartolazzi, Armando; Bellotti, Carlo; Sciacchitano, Salvatore

2012-01-01

In the last decade, the β-galactosyl binding protein galectin-3 has been the object of extensive molecular, structural, and functional studies aimed to clarify its biological role in cancer. Multicenter studies also contributed to discover the potential clinical value of galectin-3 expression analysis in distinguishing, preoperatively, benign from malignant thyroid nodules. As a consequence galectin-3 is receiving significant attention as tumor marker for thyroid cancer diagnosis, but some conflicting results mostly owing to methodological problems have been published. The possibility to apply preoperatively a reliable galectin-3 test method on fine needle aspiration biopsy (FNA)-derived thyroid cells represents an important achievement. When correctly applied, the method reduces consistently the gray area of thyroid FNA cytology, contributing to avoid unnecessary thyroid surgery. Although the efficacy and reliability of the galectin-3 test method have been extensively proved in several studies, its translation in the clinical setting requires well-standardized reagents and procedures. After a decade of experimental work on galectin-3-related basic and translational research projects, the major methodological problems that may potentially impair the diagnostic performance of galectin-3 immunotargeting are highlighted and discussed in detail. A standardized protocol for a reliable galectin-3 expression analysis is finally provided. The aim of this contribution is to improve the clinical management of patients with thyroid nodules, promoting the preoperative use of a reliable galectin-3 test method as ancillary technique to conventional thyroid FNA cytology. The final goal is to decrease unnecessary thyroid surgery and its related social costs.

Galectin-3 expression in hippocampal CA2 following transient forebrain ischemia and its inhibition by hypothermia or antiapoptotic agents

PubMed Central

Hisamatsu, Kenji; Kobayashi, Kazuhiro; Miyazaki, Tatsuhiko; Hirata, Akihiro; Hatano, Yuichiro; Tomita, Hiroyuki; Hara, Akira

2016-01-01

Recent evidence has suggested that the hippocampal CA2 region plays an important role in the recognition process. We have reported that ischemic damage in the hippocampal CA2 region following transient ischemia is caused by apoptosis, but the underlying mechanisms are still not clear. Galectin-3 is a β-galactosidase-binding lectin that is important in cell proliferation and apoptotic regulation. We have also reported that galectin-3 was expressed in activated microglia in the CA1 region 96 h after transient ischemia. The aim of this study is to determine the localization and time course of galectin-3 expression in the CA2 region following transient forebrain ischemia. Galectin-3 immunostaining was observed in both interior side of CA1 region and CA2 region in hippocampus 60 h after ischemic insult. At 66 h, galectin-3 was observed in the whole CA1 region adjacent to the CA2 region in the hippocampus. Both galectin-3 expression and neuronal cell death in the CA2 region were significantly inhibited by hypothermia and by apoptosis-inhibiting reagents. These results suggest that galectin-3 in the CA2 region is expressed independent of that in the CA1 region. Protection of the expression of galectin-3 in the CA2 region might contribute toward the survival of CA2 pyramidal neurons. PMID:26848998

Distinct cargo-specific response landscapes underpin the complex and nuanced role of galectin-glycan interactions in clathrin-independent endocytosis.

PubMed

Mathew, Mohit P; Donaldson, Julie G

2018-05-11

Clathrin-independent endocytosis (CIE) is a form of endocytosis that lacks a defined cytoplasmic machinery. Here, we asked whether glycan interactions, acting from the outside, could be a part of that endocytic machinery. We show that the perturbation of global cellular patterns of protein glycosylation by modulation of metabolic flux affects CIE. Interestingly, these changes in glycosylation had cargo-specific effects. For example, in HeLa cells, GlcNAc treatment, which increases glycan branching, increased major histocompatibility complex class I (MHCI) internalization but inhibited CIE of the glycoprotein CD59 molecule (CD59). The effects of knocking down the expression of galectin 3, a carbohydrate-binding protein and an important player in galectin-glycan interactions, were also cargo-specific and stimulated CD59 uptake. By contrast, inhibition of all galectin-glycan interactions by lactose inhibited CIE of both MHCI and CD59. None of these treatments affected clathrin-mediated endocytosis, implying that glycosylation changes specifically affect CIE. We also found that the galectin lattice tailors membrane fluidity and cell spreading. Furthermore, changes in membrane dynamics mediated by the galectin lattice affected macropinocytosis, an altered form of CIE, in HT1080 cells. Our results suggest that glycans play an important and nuanced role in CIE, with each cargo being affected uniquely by alterations in galectin and glycan profiles and their interactions. We conclude that galectin-driven effects exist on a continuum from stimulatory to inhibitory, with distinct CIE cargo proteins having unique response landscapes and with different cell types starting at different positions on these conceptual landscapes.

Galectin-7 overexpression is associated with the apoptotic process in UVB-induced sunburn keratinocytes

PubMed Central

Bernerd, Francoise; Sarasin, Alain; Magnaldo, Thierry

1999-01-01

Galectin-7 is a β-galactoside binding protein specifically expressed in stratified epithelia and notably in epidermis, but barely detectable in epidermal tumors and absent from squamous carcinoma cell lines. Galectin-7 gene is an early transcriptional target of the tumor suppressor protein P53 [Polyak, K., Xia, Y., Zweier, J., Kinzler, K. & Vogelstein, B. (1997) Nature (London) 389, 300–305]. Because p53 transcriptional activity is increased by genotoxic stresses we have examined the possible effects of ultraviolet radiations (UVB) on galectin-7 expression in epidermal keratinocytes. The amounts of galectin-7 mRNA and protein are increased rapidly after UVB irradiation of epidermal keratinocytes. The increase of galectin-7 is parallel to P53 stabilization. UVB irradiation of skin reconstructed in vitro and of human skin ex vivo demonstrates that galectin-7 overexpression is associated with sunburn/apoptotic keratinocytes. Transfection of a galectin-7 expression vector results in a significant increase in terminal deoxynucleotidyltransferase-mediated UTP end labeling-positive keratinocytes. The present findings demonstrate a keratinocyte-specific protein involved in the UV-induced apoptosis, an essential process in the maintenance of epidermal homeostasis. PMID:10500176

Both serum and tissue Galectin-1 levels are associated with adverse clinical features in neuroblastoma.

PubMed

Chen, Kai; Cai, Yuanxia; Zhang, Min; Wu, Zhixiang; Wu, Yeming

2018-05-24

Neuroblastoma is one of the most common pediatric solid tumors. Although the 5-year overall survival rate has increased over the past few decades, high-risk patients still have a poor prognosis due to a lack of biomonitoring therapy. This study was performed to investigate the role of Galectin-1 in neuroblastoma biomonitoring therapy. A tissue microarray containing 37 neuroblastoma tissue samples was used to evaluate the correlation between Galectin-1 expression and clinical features. Blood samples were examined to better understand whether serum Galectin-1 (sGalectin-1) could be used for biomonitoring therapy. Kaplan-Meier analysis and ROC analysis was conducted to distinguish the outcome associated with high or low expression of Galectin-1 in patients with neuroblastoma. Increased Galectin-1 expression was found in neuroblastoma and it was further demonstrated that elevated tissue Galectin-1 expression was related to INSS stage, histology, bone marrow metastasis, and poor survival. sGalectin-1 levels were higher in newly diagnosed patients with neuroblastoma than healthy subjects. Patients with elevated sGalectin-1 through treatment cycles correlated with the poor chemo-responses and tended to have worse outcomes, such as metastasis or stable tumor size, whereas gradually decreasing sGalectin-1 levels correlated with no observed progression in clinical symptoms. Tissue and serum Galectin-1 levels were associated with adverse clinical features in patients with neuroblastoma, and sGalectin-1 could be a potential biomarker for monitoring therapy. © 2018 Wiley Periodicals, Inc.

Modified citrus pectin stops progression of liver fibrosis by inhibiting galectin-3 and inducing apoptosis of stellate cells.

PubMed

Abu-Elsaad, Nashwa M; Elkashef, Wagdi Fawzi

2016-05-01

Modified citrus pectin (MCP) is a pH modified form of the dietary soluble citrus peel fiber known as pectin. The current study aims at testing its effect on liver fibrosis progression. Rats were injected with CCl4 (1 mL/kg, 40% v/v, i.p., twice a week for 8 weeks). Concurrently, MCP (400 or 1200 mg/kg) was administered daily in drinking water from the first week in groups I and II (prophylactic model) and in the beginning of week 5 in groups III and IV (therapeutic model). Liver function biomarkers (ATL, AST, and ALP), fibrosis markers (laminin and hyaluronic acid), and antioxidant biomarkers (reduced glutathione (GSH) and superoxide dismutase (SOD)) were measured. Stained liver sections were scored for fibrosis and necroinflammation. Additionally, expression of galectin-3 (Gal-3), α-smooth muscle actin (SMA), tissue inhibitor metalloproteinase (TIMP)-1, collagen (Col)1A1, caspase (Cas)-3, and apoptosis related factor (FAS) were assigned. Modified pectin late administration significantly (p < 0.05) decreased malondialdehyde (MDA), TIMP-1, Col1A1, α-SMA, and Gal-3 levels and increased levels of FAS, Cas-3, GSH, and SOD. It also decreased percentage of fibrosis and necroinflammation significantly (p < 0.05). It can be concluded that MCP can attenuate liver fibrosis through an antioxidant effect, inhibition of Gal-3 mediated hepatic stellate cells activation, and induction of apoptosis.

The impact of galectin-3 inhibition on aldosterone-induced cardiac and renal injuries.

PubMed

Calvier, Laurent; Martinez-Martinez, Ernesto; Miana, Maria; Cachofeiro, Victoria; Rousseau, Elodie; Sádaba, J Rafael; Zannad, Faiez; Rossignol, Patrick; López-Andrés, Natalia

2015-01-01

This study investigated whether galectin (Gal)-3 inhibition could block aldosterone-induced cardiac and renal fibrosis and improve cardiorenal dysfunction. Aldosterone is involved in cardiac and renal fibrosis that is associated with the development of cardiorenal injury. However, the mechanisms of these interactions remain unclear. Gal-3, a β-galactoside-binding lectin, is increased in heart failure and kidney injury. Rats were treated with aldosterone-salt combined with spironolactone (a mineralocorticoid receptor antagonist) or modified citrus pectin (a Gal-3 inhibitor), for 3 weeks. Wild-type and Gal-3 knockout mice were treated with aldosterone for 3 weeks. Hemodynamic, cardiac, and renal parameters were analyzed. Hypertensive aldosterone-salt-treated rats presented cardiac and renal hypertrophy (at morphometric, cellular, and molecular levels) and dysfunction. Cardiac and renal expressions of Gal-3 as well as levels of molecular markers attesting fibrosis were also augmented by aldosterone-salt treatment. Spironolactone or modified citrus pectin treatment reversed all of these effects. In wild-type mice, aldosterone did not alter blood pressure levels but increased cardiac and renal Gal-3 expression, fibrosis, and renal epithelial-mesenchymal transition. Gal-3 knockout mice were resistant to aldosterone effects. In experimental hyperaldosteronism, the increase in Gal-3 expression was associated with cardiac and renal fibrosis and dysfunction but was prevented by pharmacological inhibition (modified citrus pectin) or genetic disruption of Gal-3. These data suggest a key role for Gal-3 in cardiorenal remodeling and dysfunction induced by aldosterone. Gal-3 could be used as a new biotarget for specific pharmacological interventions. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Galectin-3 is essential for proper bone cell differentiation and activity, bone remodeling and biomechanical competence in mice.

PubMed

Iacobini, Carla; Fantauzzi, Claudia Blasetti; Bedini, Rossella; Pecci, Raffaella; Bartolazzi, Armando; Amadio, Bruno; Pesce, Carlo; Pugliese, Giuseppe; Menini, Stefano

2018-02-09

Galectin-3 is constitutively expressed in bone cells and was recently shown to modulate osteogenic transdifferentiation of vascular smooth muscle cells and atherosclerotic calcification. However, the role of galectin-3 in bone physiology is largely undefined. To address this issue, we analyzed (1) the skeletal features of 1-, 3- and 6-month-old galectin-3 null (Lgals3 -/- ) and wild type (WT) mice and (2) the differentiation and function of osteoblasts and osteoclasts derived from these animals. Long bone phenotype, gene expression profile, and remodeling were investigated by micro-computed tomography, real time-PCR, static and dynamic histomorphometry, and assessment of biochemical markers of bone resorption and formation. Bone competence was also evaluated by biomechanical testing at 3 months. In vitro, the effects of galectin-3 deficiency on bone cell differentiation and function were investigated by assessing (a) gene expression of osteoblast markers, alkaline phosphatase activity, mineralization assay, and WNT/β-catenin signaling (of which galectin-3 is a known regulator) in osteoblasts; and (b) tartrate-resistant acid phosphatase activity and bone resorption activity in osteoclasts. Lgals3 -/- mice revealed a wide range of age-dependent alterations including lower bone formation and higher bone resorption, accelerated age-dependent trabecular bone loss (p < 0.01 vs. WT at 3 months) and reduced bone strength (p < 0.01 vs. WT at 3 months). These abnormalities were accompanied by a steady inflammatory state, as revealed by higher bone expression of the pro-inflammatory cytokines interleukin (IL)-1β and IL-6 (p < 0.001 vs. WT at 3 months), increased content of osteal macrophages (p < 0.01 vs. WT at 3 months), and reduced expression of markers of alternative (M2) macrophage activation. Lgals3 -/- osteoblasts and osteoclasts showed impaired terminal differentiation, reduced mineralization capacity (p < 0.01 vs. WT cells) and resorption activity (p < 0.01 vs. WT cells). Mechanistically, impaired differentiation and function of Lgals3 -/- osteoblasts was associated with altered WNT/β-catenin signaling (p < 0.01 vs. WT cells). These data provide evidence for a contribution of galectin-3 to bone cell maturation and function, bone remodeling, and biomechanical competence, thus identifying galectin-3 as a promising therapeutic target for age-related disorders of bone remodeling. Copyright © 2018. Published by Elsevier Inc.

Simultaneous immunohistochemical expression of HBME-1 and galectin-3 differentiates papillary carcinomas from hyperfunctioning lesions of the thyroid.

PubMed

Rossi, E D; Raffaelli, M; Mule', A; Miraglia, A; Lombardi, C P; Vecchio, F M; Fadda, G

2006-06-01

The histological diagnosis is critical for the postsurgical management and follow-up of thyroid malignancies. The differential diagnosis between papillary carcinoma and hyperfunctioning lesions, either with papillary hyperplasia or with a follicular architecture, can create real diagnostic difficulty. The aim of this study was to evaluate the expression of several antibodies considered to be markers of malignancy in malignant and hyperfunctioning thyroid neoplasms and to include the most effective of them in a diagnostic panel. One hundred resected thyroid nodules--58 hyperfunctioning benign lesions and 42 papillary carcinomas (14 follicular variant, 14 macrofollicular variant and 14 classic type)--were immunohistochemically studied for HBME-1, galectin-3, cytokeratin (CK) 19 and RET-proto-oncogene. HBME-1 and galectin-3 showed 92.8% and 89% sensitivity, respectively, and their coexpression was present in 36 out of 42 papillary carcinomas (85.7%) and absent in non-malignant lesions. Their association increased sensitivity to 94.7% and the diagnostic accuracy to 97.9% and involved the highest number of cases (95%) in comparison with two other panels including, respectively, three (HBME-1, galectin-3, CK19) and all four antibodies. An immunohistochemical panel consisting of HBME-1 and galectin-3 can make a correct distinction between malignant and hyperfunctioning thyroid neoplasms with high diagnostic accuracy.

Immunohistochemical Analysis of Galectins-1, -3, and -7 in Periapical Granulomas, Radicular Cysts, and Residual Radicular Cysts.

PubMed

Brito, Lívia Natália Sales; de Lemos Almeida, Maria Manuela Rodrigues; de Souza, Lélia Batista; Alves, Pollianna Muniz; Nonaka, Cassiano Francisco Weege; Godoy, Gustavo Pina

2018-05-01

Galectins play important roles in immunoinflammatory responses, but their participation in the development of periapical lesions remains unclear. This study aimed to evaluate the expressions of galectins-1, -3, and -7 in periapical lesions, correlating them with the intensity of the inflammatory infiltrate and the pattern of the cystic epithelium. Twenty periapical granulomas (PGs), 20 radicular cysts (RCs), and 20 residual radicular cysts (RRCs) were submitted to immunohistochemistry using anti-galectin-1, -3, and -7 antibodies. The percentage of immunopositive cells in epithelial and connective tissues was determined. In connective tissue, PGs exhibited higher cytoplasmic/membrane expression of galectins-1 and -7 than RCs and RRCs (P < .05). There was higher nuclear expression of galectin-1 in PGs compared with RCs and RRCs (P < .05). The expression of galectins-1 and -7 in connective tissue was higher in lesions with grade III inflammation (P < .05). No significant differences in galectin-3 immunoexpression were observed for any of the parameters evaluated (P > .05). In the epithelial component, a higher nuclear expression of galectin-7 was detected in RRCs (P < .05), and a higher cytoplasmic/membrane expression of this protein was found in cysts with hyperplastic epithelium (P < .05). Positive correlations were observed between the nuclear and cytoplasmic/membrane expression of galectin-1 in connective tissue (P < .05) as well as between the nuclear and cytoplasmic/membrane expression of galectin-7 in epithelial tissue of cysts (P < .05). Galectins-1 and -7 may play important roles in the pathogenesis of PGs, RCs, and RRCs. On the other hand, the present results suggest only a minor involvement of galectin-3 in the development of these lesions. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Galectin-1 suppresses alpha2(I) collagen through Smad3 in renal epithelial cells.

PubMed

Okano, K; Uchida, K; Nitta, K; Hayashida, T

2008-10-01

Transforming growth factor (TGF-beta1) promotes renal fibrogenesis through activation of Smads. Galectin-1 is reported to prevent experimental glomerulonephritis. Here we investigated the fact that transfected galectin-1 significantly suppressed the transcription of alpha2(I) collagen (COL1A2) in TGF-beta1- activated human renal epithelial cells. Conversely, galectin-1 silencing RNA reduced secretion of type I collagen by HKC cells. Galectin-1 significantly decreased activation of a TGF-beta1-responsive reporter construct and of a minimal reporter construct that contains four repeats of the Smad binding element (SBE). Galectin-1 had no effect on phosphorylation of Smad3 at the linker region and C-terminus, whereas it decreased affinity of Smad3 to the SBE. Additionally, the inhibitory effect of galectin-1 disappeared using a mutated reporter construct, 376 m-LUC, in which a potential Smad recognition site within the promoter is mutated. Taken together, the results suggest that galectin-1 decreases Smad3-complex from binding to the SBE, down-regulating transcription of COL1A2 in TGF-beta1-stimulated renal epithelial cells.

Nanoparticle Based Galectin-1 Gene Silencing, Implications in Methamphetamine Regulation of HIV-1 Infection in Monocyte Derived Macrophages

PubMed Central

Law, Wing Cheung; Mahajan, Supriya D.; Aalinkeel, Ravikumar; Nair, Bindukumar; Sykes, Donald E.; Yong, Ken-Tye; Hui, Rui; Prasad, Paras N.; Schwartz, Stanley A.

2012-01-01

Galectin-1, an adhesion molecule, is expressed in macrophages and implicated in human immunodeficiency virus (HIV-1) viral adsorption. In this study, we investigated the effects of methamphetamine on galectin-1 production in human monocyte derived macrophages (MDM) and the role of galectin-1 in methamphetamine potentiation of HIV-1 infection. Herein we show that levels of galectin-1 gene and protein expression are significantly increased by meth-amphetamine. Furthermore, concomitant incubation of MDM with galectin-1 and methamphetamine facilitates HIV-1 infection compared to galectin-1 alone or methamphetamine alone. We utilized a nanotechnology approach that uses gold nanorod (GNR)-galectin-1 siRNA complexes (nanoplexes) to inhibit gene expression for galectin-1. Nanoplexes significantly silenced gene expression for galectin-1 and reversed the effects of methamphetamine on galectin-1 gene expression. Moreover, the effects of methamphetamine on HIV-1 infection were attenuated in the presence of the nanoplex in MDM. PMID:22689223

Immunohistochemical expression of galectin-3 is significantly associated with grade, stage and differentiation of endometrial carcinomas.

PubMed

Al-Maghrabi, Jaudah; Abdelrahman, Amer Shafie; Ghabrah, Tawfik; Butt, Nadeem Shafique; Al-Maghrabi, Basim; Khabaz, Mohamad Nidal

2017-04-01

This study describes galectin-3 immunohistochemical phenotype and its association with clinicopathological factors in the carcinoma of endometrium. Seventy one cases of endometrial carcinoma and 30 cases of benign and normal endometrium were employed for the detection of galectin-3 protein using tissue microarrays and immunohistochemistry staining. Thirty nine (55%) cases, including 54.2% of endometrioid adenocarcinomas and 55.5% serous carcinomas, were positively stained for galectin-3. Brown granular expression of this glycoprotein was detected in transformed epithelial cells of 36 cases including 28 cases with membranous and cytoplasmic staining and 8 cases with only cytoplasmic staining; nuclear expression was present in stromal cells of the remaining 3 cases. Twenty-four (80%) control cases showed granular cytoplasmic and membranous expression, and six control cases were negative. Tumor grade, stage and differentiation were significantly associated with galectin-3 immunoreactivity (p-values are 0.043, 0.016, and 0.044 respectively), cases with membranous and cytoplasmic staining is significantly associated with grade I and stage II, while cases with loss of staining are more frequent in grade II, III and poorly differentiated tumors. No significant association of galectin-3 staining was observed with age, diagnosis, recurrence and alive status. The current study supports the tumor suppression role of galectin-3 in endometrial carcinoma. Greater galectin-3 immunostaining has been found in control endometrial tissues compared to endometrial tumors. Loss or decreased galectin-3 immunoexpression gives a sign for poor prognoses in endometrial carcinoma patients. Copyright © 2017 Elsevier GmbH. All rights reserved.

Diagnostic and Prognostic Significance of Serum and Tissue Galectin 3 Expression in Patients with Carcinoma of the Bladder

PubMed Central

Gendy, Hoda El; Madkour, Bothina; Abdelaty, Sara; Essawy, Fayza; Khattab, Dina; Hammam, Olfat; Nour, Hani H.

2014-01-01

Background Galectins are group of proteins found in the cytoplasm, nucleus, cell surface and extracellular matrix. Galectin 3 (Gal-3) displays pathological expression in a variety of processes such as tumorigenesis. Patients and Method 70 patients classified into the control group, cystitis group, transitional cell carcinoma group, and squamous cell carcinoma group were enrolled in this study which aimed to detect the serum level and the intensity of tissue expression of Gal-3. Results Both serum level and tissue expression of Gal-3 were statistically higher in bladder cancer patients compared to the other groups. Gal-3 level expression increased from low to high grade urothelial tumors, with a statistically significant increase of its level and expression between muscle invasive and non-muscle invasive Ta urothelial tumors. Conclusion The serum Gal-3 level is sensitive and specific for the diagnosis of bladder cancer. The prognostic significance of tissue expression is to be confirmed. PMID:26195948

Structural changes in hair follicles and sebaceous glands of hairless mice following exposure to sulfur mustard.

PubMed

Joseph, Laurie B; Heck, Diane E; Cervelli, Jessica A; Composto, Gabriella M; Babin, Michael C; Casillas, Robert P; Sinko, Patrick J; Gerecke, Donald R; Laskin, Debra L; Laskin, Jeffrey D

2014-06-01

Sulfur mustard (SM) is a bifunctional alkylating agent causing skin inflammation, edema and blistering. A hallmark of SM-induced toxicity is follicular and interfollicular epithelial damage. In the present studies we determined if SM-induced structural alterations in hair follicles and sebaceous glands were correlated with cell damage, inflammation and wound healing. The dorsal skin of hairless mice was treated with saturated SM vapor. One to seven days later, epithelial cell karyolysis within the hair root sheath, infundibulum and isthmus was apparent, along with reduced numbers of sebocytes. Increased numbers of utriculi, some with connections to the skin surface, and engorged dermal cysts were also evident. This was associated with marked changes in expression of markers of DNA damage (phospho-H2A.X), apoptosis (cleaved caspase-3), and wound healing (FGFR2 and galectin-3) throughout pilosebaceous units. Conversely, fatty acid synthase and galectin-3 were down-regulated in sebocytes after SM. Decreased numbers of hair follicles and increased numbers of inflammatory cells surrounding the utriculi and follicular cysts were noted within the wound 3-7 days post-SM exposure. Expression of phospho-H2A.X, cleaved caspase-3, FGFR2 and galectin-3 was decreased in dysplastic follicular epidermis. Fourteen days after SM, engorged follicular cysts which expressed galectin-3 were noted within hyperplastic epidermis. Galectin-3 was also expressed in basal keratinocytes and in the first few layers of suprabasal keratinocytes in neoepidermis formed during wound healing indicating that this lectin is important in the early stages of keratinocyte differentiation. These data indicate that hair follicles and sebaceous glands are targets for SM in the skin. Copyright © 2014 Elsevier Inc. All rights reserved.

Galectin-3 in angiogenesis and metastasis

PubMed Central

Funasaka, Tatsuyoshi; Raz, Avraham; Nangia-Makker, Pratima

2014-01-01

Galectin-3 is a member of the family of β-galactoside-binding lectins characterized by evolutionarily conserved sequences defined by structural similarities in their carbohydrate-recognition domains. Galectin-3 is a unique, chimeric protein consisting of three distinct structural motifs: (i) a short NH2 terminal domain containing a serine phosphorylation site; (ii) a repetitive proline-rich collagen-α-like sequence cleavable by matrix metalloproteases; and (iii) a globular COOH-terminal domain containing a carbohydrate-binding motif and an NWGR anti-death motif. It is ubiquitously expressed and has diverse biological functions depending on its subcellular localization. Galectin-3 is mainly found in the cytoplasm, also seen in the nucleus and can be secreted by non-classical, secretory pathways. In general, secreted galectin-3 mediates cell migration, cell adhesion and cell–cell interactions through the binding with high affinity to galactose-containing glycoproteins on the cell surface. Cytoplasmic galectin-3 exhibits anti-apoptotic activity and regulates several signal transduction pathways, whereas nuclear galectin-3 has been associated with pre-mRNA splicing and gene expression. Its unique chimeric structure enables it to interact with a plethora of ligands and modulate diverse functions such as cell growth, adhesion, migration, invasion, angiogenesis, immune function, apoptosis and endocytosis emphasizing its significance in the process of tumor progression. In this review, we have focused on the role of galectin-3 in tumor metastasis with special emphasis on angiogenesis. PMID:25138305

Shiga toxin 1 interaction with enterocytes causes apical protein mistargeting through the depletion of intracellular galectin-3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laiko, Marina; Murtazina, Rakhilya; Malyukova, Irina

Shiga toxins (Stx) 1 and 2 are responsible for intestinal and systemic sequelae of infection by enterohemorrhagic Escherichia coli (EHEC). However, the mechanisms through which enterocytes are damaged remain unclear. While secondary damage from ischemia and inflammation are postulated mechanisms for all intestinal effects, little evidence excludes roles for more primary toxin effects on intestinal epithelial cells. We now document direct pathologic effects of Stx on intestinal epithelial cells. We study a well-characterized rabbit model of EHEC infection, intestinal tissue and stool samples from EHEC-infected patients, and T84 intestinal epithelial cells treated with Stx1. Toxin uptake by intestinal epithelial cellsmore » in vitro and in vivo causes galectin-3 depletion from enterocytes by increasing the apical galectin-3 secretion. This Shiga toxin-mediated galectin-3 depletion impairs trafficking of several brush border structural proteins and transporters, including villin, dipeptidyl peptidase IV, and the sodium-proton exchanger 2, a major colonic sodium absorptive protein. The mistargeting of proteins responsible for the absorptive function might be a key event in Stx1-induced diarrhea. These observations provide new evidence that human enterocytes are directly damaged by Stx1. Conceivably, depletion of galectin-3 from enterocytes and subsequent apical protein mistargeting might even provide a means whereby other pathogens might alter intestinal epithelial absorption and produce diarrhea.« less

Up-regulation of neogenin-1 increases cell proliferation and motility in gastric cancer

PubMed Central

Kim, Seok-Jun; Wang, Yuan-Guo; Lee, Hyun-Woo; Gu Kang, Hyeok; La, Sun-Hyuk; Ju Choi, Il; Irimura, Tatsuro; Ro, Jae Y.; Bresalier, Robert S.; Chun, Kyung-Hee

2014-01-01

Although elevated expression of neogenin-1 has been detected in human gastric cancer tissue, its role in gastric tumorigenesis remains unclear due to the lack of neogenin-1 studies in cancer. Therefore, we demonstrated here the function and regulatory mechanism of neogenin-1 in gastric cancer. Neogenin-1 ablation decreased proliferation and migration of gastric cancer cells, whereas its over-expression reversed these effects. Xenografted analyses using gastric cancer cells displayed statistically significant inhibition of tumor growth by neogenin-1 depletion. Interestingly, galectin-3 interacted with HSF-1 directly, which facilitated nuclear-localization and binding on neogenin-1 promoter to drive its transcription and gastric cancer cell motility. The galectin-3-increased gastric cancer cell motility was down-regulated by HSF-1 depletion. Moreover, the parallel expression patterns of galectin-3 and neogenin-1, as well as those of HSF-1 and neogenin-1, were detected in the malignant tissues of gastric cancer patients. Taken together, high-expression of neogenin-1 promotes gastric cancer proliferation and motility and its expression is regulated by HSF-1 and galectin-3 interaction. In addition, we propose further studies for neogenin-1 and its associated pathways to provide them as a proper target for gastric cancer therapy. PMID:24930499

The involvement of galectin-3 in skin injury in systemic lupus erythematosus patients.

PubMed

Shi, Z; Meng, Z; Han, Y; Cao, C; Tan, G; Wang, L

2018-04-01

Objective Our previous research suggested that anti-galectin-3 antibody was highly associated with the development of lupus skin lesions in systemic lupus erythematosus (SLE). In this study we aimed to investigate the involvement of galectin-3 in SLE skin damage. Methods The study consisted of 49 patients with SLE, 16 with dermatomyositis and 11 with systemic scleroderma and 20 healthy controls. Galectin-3 was examined by ELISA and immunohistochemical staining in serum and skin, respectively. Results Serum galectin-3 was significantly higher in patients with SLE than in those with dermatomyositis ( P < 0.01), systemic scleroderma ( P < 0.001) and healthy controls ( P < 0.001); however, it was comparable between SLE patients with and without skin lesions ( P = 0.2010 and was not correlated with cutaneous disease activity ( r = -0.020, P = 0.93) or damage score ( r = -0.380, P = 0.09). Galectin-3 expression was reduced in epidermis in lesional skin from patients with SLE, dermatomyositis and systemic scleroderma compared to healthy controls ( P = 0.0055), whereas it was comparable among diseases ( P > 0.05). As for subtypes of skin lesions in SLE, galectin-3 expression was lower in chronic cutaneous lupus erythematosus than in acute cutaneous lupus erythematosus ( P = 0.0439). Conclusion Serum galectin-3 is unlikely to play a role in the pathogenesis of lupus skin damage, but can be a potential biomarker for the measurement of SLE disease activity. Galectin-3 is greatly reduced in patients with lupus lesions compared with healthy controls, which may contribute to the recruitment of inflammatory cells in the skin.

Endogenous galectin-3 expression levels modulate immune responses in galectin-3 transgenic mice.

PubMed

Chaudhari, Aparna D; Gude, Rajiv P; Kalraiya, Rajiv D; Chiplunkar, Shubhada V

2015-12-01

Galectin-3 (Gal-3), a β-galactoside-binding mammalian lectin, is involved in cancer progression and metastasis. However, there is an unmet need to identify the underlying mechanisms of cancer metastasis mediated by endogenous host galectin-3. Galectin-3 is also known to be an important regulator of immune responses. The present study was aimed at analysing how expression of endogenous galectin-3 regulates host immunity and lung metastasis in B16F10 murine melanoma model. Transgenic Gal-3(+/-) (hemizygous) and Gal-3(-/-) (null) mice exhibited decreased levels of Natural Killer (NK) cells and lower NK mediated cytotoxicity against YAC-1 tumor targets, compared to Gal-3(+/+) (wild-type) mice. On stimulation, Gal-3(+/-) and Gal-3(-/-) mice splenocytes showed increased T cell proliferation than Gal-3(+/+) mice. Intracellular calcium flux was found to be lower in activated T cells of Gal-3(-/-) mice as compared to T cells from Gal-3(+/+) and Gal-3(+/-) mice. In Gal-3(-/-) mice, serum Th1, Th2 and Th17 cytokine levels were found to be lowest, exhibiting dysregulation of pro-inflammatory and anti-inflammatory cytokines balance. Marked decrease in serum IFN-γ levels and splenic IFN-γR1 (IFN-γ Receptor 1) expressing T and NK cell percentages were observed in Gal-3(-/-) mice. On recombinant IFN-γ treatment of splenocytes in vitro, Suppressor of Cytokine Signaling (SOCS) 1 and SOCS3 protein expression was higher in Gal-3(-/-) mice compared to that in Gal-3(+/+) and Gal-3(+/-) mice; suggesting possible attenuation of Signal Transducer and Activator of Transcription (STAT) 1 mediated IFN-γ signaling in Gal-3(-/-) mice. The ability of B16F10 melanoma cells to form metastatic colonies in the lungs of Gal-3(+/+) and Gal-3(-/-) mice remained comparable, whereas it was found to be reduced in Gal-3(+/-) mice. Our data indicates that complete absence of endogenous host galectin-3 facilitates lung metastasis of B16F10 cells in mice, which may be contributed by dysregulated immune responses resulting from decreased NK cytotoxicity, disturbed serum Th1, Th2, Th17 cytokine milieu, reduced serum IFN-γ levels and attenuation of splenic STAT1 mediated IFN-γ signalling in Gal-3(-/-) mice. Copyright © 2015 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin Lim, Min; Ahn, Jiyeon; Youn Yi, Jae

Fibrosis is one of the most serious side effects in cancer patients undergoing radio-/ chemo-therapy, especially of the lung, pancreas or kidney. Based on our previous finding that galectin-1 (Gal-1) was significantly increased during radiation-induced lung fibrosis in areas of pulmonary fibrosis, we herein clarified the roles and action mechanisms of Gal-1 during fibrosis. Our results revealed that treatment with TGF-β1 induced the differentiation of fibroblast cell lines (NIH3T3 and IMR-90) to myofibroblasts, as evidenced by increased expression of the fibrotic markers smooth muscle actin-alpha (α-SMA), fibronectin, and collagen (Col-1). We also observed marked and time-dependent increases in the expressionmore » level and nuclear accumulation of Gal-1. The TGF-β1-induced increases in Gal-1, α-SMA and Col-1 were decreased by inhibitors of PI3-kinase and p38 MAPK, but not ERK. Gal-1 knockdown using shRNA decreased the phosphorylation and nuclear retention of Smad2, preventing the differentiation of fibroblasts. Gal-1 interacted with Smad2 and phosphorylated Smad2, which may accelerate fibrotic processes. In addition, up-regulation of Gal-1 expression was demonstrated in a bleomycin (BLM)-induced mouse model of lung fibrosis in vivo. Together, our results indicate that Gal-1 may promote the TGF-β1-induced differentiation of fibroblasts by sustaining nuclear localization of Smad2, and could be a potential target for the treatment of pulmonary fibrotic diseases. - Highlights: • Galectin-1 (Gal-1) promotes TGF-β-induced fibroblast differentiation via activation of PI3-kinase and p38 MAPK. • Gal-1 binds to Smad2 and phosphorylated Smad2. • GAl-1 may be a new therapeutic target for attenuating lung fibrotic process.« less

Prototype and Chimera-Type Galectins in Placentas with Spontaneous and Recurrent Miscarriages.

PubMed

Unverdorben, Laura; Haufe, Thomas; Santoso, Laura; Hofmann, Simone; Jeschke, Udo; Hutter, Stefan

2016-04-28

Galectins are galactose binding proteins and, in addition, factors for a wide range of pathologies in pregnancy. We have analyzed the expression of prototype (gal-1, -2, -7, -10) and chimera-type (gal-3) galectins in the placenta in cases of spontaneous abortions (SPA) and recurrent abortions (RA) in the first trimester. Fifteen placental samples from healthy pregnancies were used as a control group. Nine placentas were examined for spontaneous abortions, and 12 placentas for recurrent abortions. For differentiation and evaluation of different cell types of galectin-expression in the decidua, immunofluorescence was used. For all investigated prototype galectins (gal-1, -2, -7, -10) in SPA and RA placenta trophoblast cells the expression is significantly decreased. In the decidua/extravillous trophoblast only gal-2 expression was significantly lowered, which could be connected to its role in angiogenesis. In trophoblasts in first-trimester placentas and in cases of SPA and RA, prototype galectins are altered in the same way. We suspect prototype galectins have a similar function in placental tissue because of their common biochemical structure. Expression of galectin 3 as a chimera type galectin was not found to be significantly altered in abortive placentas.

Prototype and Chimera-Type Galectins in Placentas with Spontaneous and Recurrent Miscarriages

PubMed Central

Unverdorben, Laura; Haufe, Thomas; Santoso, Laura; Hofmann, Simone; Jeschke, Udo; Hutter, Stefan

2016-01-01

Galectins are galactose binding proteins and, in addition, factors for a wide range of pathologies in pregnancy. We have analyzed the expression of prototype (gal-1, -2, -7, -10) and chimera-type (gal-3) galectins in the placenta in cases of spontaneous abortions (SPA) and recurrent abortions (RA) in the first trimester. Fifteen placental samples from healthy pregnancies were used as a control group. Nine placentas were examined for spontaneous abortions, and 12 placentas for recurrent abortions. For differentiation and evaluation of different cell types of galectin-expression in the decidua, immunofluorescence was used. For all investigated prototype galectins (gal-1, -2, -7, -10) in SPA and RA placenta trophoblast cells the expression is significantly decreased. In the decidua/extravillous trophoblast only gal-2 expression was significantly lowered, which could be connected to its role in angiogenesis. In trophoblasts in first-trimester placentas and in cases of SPA and RA, prototype galectins are altered in the same way. We suspect prototype galectins have a similar function in placental tissue because of their common biochemical structure. Expression of galectin 3 as a chimera type galectin was not found to be significantly altered in abortive placentas. PMID:27136536

Anti-viral activity of galectin-1 from flounder Paralichthys olivaceus.

PubMed

Liu, Shousheng; Hu, Guobin; Sun, Chen; Zhang, Shicui

2013-06-01

Galectins are a family of Ca(2+)-independent soluble lectins characterized by their affinity to β-galactosides. Mammalian galectins have been shown to play a defense role against certain bacteria, fungi and viruses. However, the immunological functions of galectins in fish is poorly characterized. Here we demonstrated that the expression of galectin-1 gene from the flounder Paralichthys olivaceus was decreased in the initial 8 h after challenge with poly I:C, then increased markedly from 24 h onwards, and the recombinant galectin-1 was able to neutralize the lymphocystis disease virus (LCDV), inhibiting the formation of cytopathic effects. In addition, the recombinant galectin had a potential anti-inflammatory activity against infection by LCDV, and was able to restrain the overexpression of the anti-viral protein gene mx against virus infection. These results indicate that flounder galectin-1 has an anti-viral activity, capable of reducing LCDV pathogenicity. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Role of Galectins in Cervical Cancer Biology and Progression.

PubMed

Wang, Lufang; Zhao, Yanyan; Wang, Yanshi; Wu, Xin

2018-01-01

Cervical cancer is one of the malignant tumors with high incidence and high mortality among women in developing countries. The main factors affecting the prognosis of cervical cancer are the late recurrence and metastasis and the effective adjuvant treatment, which is radiation and chemotherapy or combination therapy. Galectins, a family containing many carbohydrate binding proteins, are closely involved in the occurrence and development of tumor. They are involved in tumor cells transformation, angiogenesis, metastasis, immune escape, and sensitivity against radiation and chemotherapy. Therefore, galectins are deemed as the targets of multifunctional cancer treatment. In this review, we mainly focus on the role of galectins, especially galectin-1, galectin-3, galectin-7, and galectin-9 in cervical cancer, and provide theoretical basis for potential targeted treatment of cervical cancer.

Noninvasive small-animal imaging of galectin-1 upregulation for predicting tumor resistance to radiotherapy.

PubMed

Lai, Jianhao; Lu, Dehua; Zhang, Chenran; Zhu, Hua; Gao, Liquan; Wang, Yanpu; Bao, Rui; Zhao, Yang; Jia, Bing; Wang, Fan; Yang, Zhi; Liu, Zhaofei

2018-03-01

Increasing evidence indicates that the overexpression of galectin-1, a member of the galectin family, is related to tumor progression and invasion, as well as tumor resistance to therapies (e.g., radiotherapy). Herein, we investigated whether near-infrared fluorescence (NIRF) imaging and positron-emission tomography (PET) were sensitive approaches for detecting and quantitating galectin-1 upregulation in vivo. An anti-galectin-1 antibody was labeled with either an NIRF dye or 64 Cu, and NIRF and PET imaging using the resulting probes (Dye-αGal-1 and 64 Cu- 1,4,7-triazacyclononane-1,4,7-triacetic acid [NOTA]-αGal-1) were performed in 4T1 breast cancer-bearing mice treated with several rounds of sorafenib. Radiotherapy was performed in vitro and in vivo to identify the role of galectin-1 in radioresistance. NIRF and PET imaging both revealed significantly increased upregulation of galectin-1 in the hypoxic tumors after sorafenib treatment, which was verified by ex vivo biodistribution, western blotting, and enzyme-linked immunosorbent assays. Galectin-1 specific inhibition by thiodigalactoside dramatically improved the efficacy of radiotherapy, and overcame sorafenib-induced radiotherapy resistance. Taken together, galectin-1 is a key mediator of tumor resistance to radiotherapy. Targeted molecular imaging allows for real-time, noninvasive, and quantitative detection of the dynamic changes in galectin-1 levels in vivo; this introduces the possibility of early detection of tumor resistance to therapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

The GALA study: relationship between galectin-3 serum levels and short- and long-term outcomes of patients with acute heart failure.

PubMed

Miró, Òscar; González de la Presa, Bernardino; Herrero-Puente, Pablo; Fernández Bonifacio, Rosa; Möckel, Martin; Mueller, Christian; Casals, Gregori; Sandalinas, Silvia; Llorens, Pere; Martín-Sánchez, Francisco Javier; Jacob, Javier; Bedini, José Luis; Gil, Víctor

2017-12-01

We tested the hypothesis that early measurement of galectin-3 at the emergency department (ED) during an episode of acute heart failure (AHF) allows predicting short- and long-term outcomes. We performed an exploratory study including 115 patients consecutively diagnosed with AHF in a single ED. Clinical and analytical variables were recorded. The primary endpoint was 30-day all-cause mortality, and secondary endpoints were 30-day composite outcome (death, rehospitalization or ED reconsultation, whichever first) and 1-year mortality. Seven patients (6.1%) died within 30 days and 43 (37.4%) within 1 year. The 30-day composite endpoint was observed in 21.1% of patients. Galectin-3 was correlated with NT-proBNP and the glomerular filtration rate but not with age and s-cTnI. Measured at time of ED arrival, galectin-3 showed good discriminatory capacity for 30-day mortality (AUC ROC: 0.732; 95% CI 0.512-0.953; p = 0.041) but not for 1-year mortality (0.521; 0.408-0.633; p = 0.722). Patients with galectin-3 concentrations >42 μg/L had an OR = 7.67(95%CI = 1.57-37.53; p = 0.012) for 30-day mortality. Conversely, NT-proBNP only showed predictive capacity for 1-year mortality (0.642; 0.537-0.748; p = 0.014). Patients with NT-proBNP concentrations >5400 ng/L had an OR = 4.34 (95%CI = 1.93-9.77; p < 0.001) for 1-year mortality. These increased short- (galectin-3) and long-term (NT-proBNP) risks remained significant after adjustment for age or renal function. s-cTnI failed in both short- and long term death prediction. No biomarker predicted the short-term composite endpoint. These results suggest that galectin-3 could help to monitor the risk of short-term mortality in unselected patients with AHF attended in the ED.

TIM-3 Does Not Act as a Receptor for Galectin-9

PubMed Central

Leitner, Judith; Rieger, Armin; Pickl, Winfried F.; Zlabinger, Gerhard; Grabmeier-Pfistershammer, Katharina; Steinberger, Peter

2013-01-01

T cell immunoglobulin and mucin protein 3 (TIM-3) is a type I cell surface protein that was originally identified as a marker for murine T helper type 1 cells. TIM-3 was found to negatively regulate murine T cell responses and galectin-9 was described as a binding partner that mediates T cell inhibitory effects of TIM-3. Moreover, it was reported that like PD-1 the classical exhaustion marker, TIM-3 is up-regulated in exhausted murine and human T cells and TIM-3 blockade was described to restore the function of these T cells. Here we show that the activation of human T cells is not affected by the presence of galectin-9 or antibodies to TIM-3. Furthermore, extensive studies on the interaction of galectin-9 with human and murine TIM-3 did not yield evidence for specific binding between these molecules. Moreover, profound differences were observed when analysing the expression of TIM-3 and PD-1 on T cells of HIV-1-infected individuals: TIM-3 was expressed on fewer cells and also at much lower levels. Furthermore, whereas PD-1 was preferentially expressed on CD45RA−CD8 T cells, the majority of TIM-3-expressing CD8 T cells were CD45RA+. Importantly, we found that TIM-3 antibodies were ineffective in increasing anti-HIV-1 T cell responses in vitro, whereas PD-L antibodies potently reverted the dysfunctional state of exhausted CD8 T cells. Taken together, our results are not in support of an interaction between TIM-3 and galectin-9 and yield no evidence for a functional role of TIM-3 in human T cell activation. Moreover, our data indicate that PD-1, but not TIM-3, is a promising target to ameliorate T cell exhaustion. PMID:23555261

A New Human 3D-Liver Model Unravels the Role of Galectins in Liver Infection by the Parasite Entamoeba histolytica

PubMed Central

Petropolis, Debora B.; Faust, Daniela M.; Deep Jhingan, Gagan; Guillen, Nancy

2014-01-01

Investigations of human parasitic diseases depend on the availability of appropriate in vivo animal models and ex vivo experimental systems, and are particularly difficult for pathogens whose exclusive natural hosts are humans, such as Entamoeba histolytica, the protozoan parasite responsible for amoebiasis. This common infectious human disease affects the intestine and liver. In the liver sinusoids E. histolytica crosses the endothelium and penetrates into the parenchyma, with the concomitant initiation of inflammatory foci and subsequent abscess formation. Studying factors responsible for human liver infection is hampered by the complexity of the hepatic environment and by the restrictions inherent to the use of human samples. Therefore, we built a human 3D-liver in vitro model composed of cultured liver sinusoidal endothelial cells and hepatocytes in a 3D collagen-I matrix sandwich. We determined the presence of important hepatic markers and demonstrated that the cell layers function as a biological barrier. E. histolytica invasion was assessed using wild-type strains and amoebae with altered virulence or different adhesive properties. We showed for the first time the dependence of endothelium crossing upon amoebic Gal/GalNAc lectin. The 3D-liver model enabled the molecular analysis of human cell responses, suggesting for the first time a crucial role of human galectins in parasite adhesion to the endothelial cells, which was confirmed by siRNA knockdown of galectin-1. Levels of several pro-inflammatory cytokines, including galectin-1 and -3, were highly increased upon contact of E. histolytica with the 3D-liver model. The presence of galectin-1 and -3 in the extracellular medium stimulated pro-inflammatory cytokine release, suggesting a further role for human galectins in the onset of the hepatic inflammatory response. These new findings are relevant for a better understanding of human liver infection by E. histolytica. PMID:25211477

Galectin-3 Functions as an Alarmin: Pathogenic Role for Sepsis Development in Murine Respiratory Tularemia

PubMed Central

Mishra, Bibhuti B.; Li, Qun; Steichen, Anthony L.; Binstock, Brandilyn J.; Metzger, Dennis W.; Teale, Judy M.; Sharma, Jyotika

2013-01-01

Sepsis is a complex immune disorder with a mortality rate of 20–50% and currently has no therapeutic interventions. It is thus critical to identify and characterize molecules/factors responsible for its development. We have recently shown that pulmonary infection with Francisella results in sepsis development. As extensive cell death is a prominent feature of sepsis, we hypothesized that host endogenous molecules called alarmins released from dead or dying host cells cause a hyperinflammatory response culminating in sepsis development. In the current study we investigated the role of galectin-3, a mammalian β-galactoside binding lectin, as an alarmin in sepsis development during F. novicida infection. We observed an upregulated expression and extracellular release of galectin-3 in the lungs of mice undergoing lethal pulmonary infection with virulent strain of F. novicida but not in those infected with a non-lethal, attenuated strain of the bacteria. In comparison with their wild-type C57Bl/6 counterparts, F. novicida infected galectin-3 deficient (galectin-3−/−) mice demonstrated significantly reduced leukocyte infiltration, particularly neutrophils in their lungs. They also exhibited a marked decrease in inflammatory cytokines, vascular injury markers, and neutrophil-associated inflammatory mediators. Concomitantly, in-vitro pre-treatment of primary neutrophils and macrophages with recombinant galectin-3 augmented F. novicida-induced activation of these cells. Correlating with the reduced inflammatory response, F. novicida infected galectin-3−/− mice exhibited improved lung architecture with reduced cell death and improved survival over wild-type mice, despite similar bacterial burden. Collectively, these findings suggest that galectin-3 functions as an alarmin by augmenting the inflammatory response in sepsis development during pulmonary F. novicida infection. PMID:23527230

Proteomic analysis identifies a novel function for galectin-3 in the cell entry of parvovirus.

PubMed

Garcin, Pierre; Cohen, Sarah; Terpstra, Sanne; Kelly, Isabelle; Foster, Leonard J; Panté, Nelly

2013-02-21

Cellular factors associated with the parvovirus minute virus of mice (MVM) during infection are thought to play important roles in the MVM life cycle but only a few of these have been identified. Here we used a proteomic-based approach in order to identify host-binding partners of MVM. Using purified MVM as bait for immunoprecipitation assays, a total of 150 proteins were identified in MVM immunoprecipitates by quantitative liquid chromatography-tandem mass spectrometry. Galectin-3 was one of six proteins showing a statistically significant enrichment across replicates. Small interfering RNA depletion studies revealed an important role for galectin-3 in MVM endocytosis and infectivity in LA9 mouse fibroblast cells. Galectin-3-depleted cells were less susceptible to MVM infection than control cells and showed a significant reduction of MVM cellular uptake, but not of MVM binding to the cell surface. Our results indicate an important role for galectin-3 in the cellular uptake of MVM. We propose that galectin-3 facilitates the access of MVM to its receptor(s) at the plasma membrane and in this way promotes MVM endocytosis. Copyright © 2012 Elsevier B.V. All rights reserved.

Morphine and galectin-1 modulate HIV-1 infection of human monocytes-derived macrophages

PubMed Central

Reynolds, Jessica L.; Law, Wing Cheung; Mahajan, Supriya D.; Aalinkeel, Ravikumar; Nair, Bindukumar; Sykes, Donald E.; Mammen, Manoj J.; Yong, Ken-Tye; Hui, Rui; Prasad, Paras N.; Schwartz, Stanley A.

2012-01-01

Morphine is a widely abused, addictive drug that modulates immune function. Macrophages are a primary reservoir of HIV-1; therefore, they not only play a role in the development of this disease but also impact the overall course of disease progression. Galectin-1 is a member of a family of β-galactoside-binding lectins that are soluble adhesion molecules and that mediate direct cell-pathogen interactions during HIV-1 viral adhesion. Since the drug abuse epidemic and the HIV-1 epidemic are closely interrelated we propose that increased expression of galectin-1 induced by morphine may modulate HIV-1 infection of human monocytes-derived macrophages (MDM). Here, we show that galectin-1 gene and protein expression are potentiated by incubation with morphine. Confirming previous studies, morphine alone or galectin-1 alone enhance HIV-1 infection of MDM. Concomitant incubation with exogenous galectin-1 and morphine potentiated HIV-1 infection of MDM. We utilized a nanotechnology approach that uses gold nanorod-galectin-1 siRNA complexes (nanoplexes) to inhibit gene expression for galectin-1. We found that nanoplexes silenced gene expression for galectin-1 and the nanoplexes reversed the effects of morphine on galectin-1 expression. Furthermore, the effects of morphine on HIV-1 infection were reduced in the presence of the nanoplex. PMID:22430735

Structural characterization of human galectin-4 C-terminal domain: elucidating the molecular basis for recognition of glycosphingolipids, sulfated saccharides and blood group antigens.

PubMed

Bum-Erdene, Khuchtumur; Leffler, Hakon; Nilsson, Ulf J; Blanchard, Helen

2015-09-01

Human galectin-4 is a lectin that is expressed mainly in the gastrointestinal tract and exhibits metastasis-promoting roles in some cancers. Its tandem-repeat nature exhibits two distinct carbohydrate recognition domains allowing crosslinking by simultaneous binding to sulfated and non-sulfated (but not sialylated) glycosphingolipids and glycoproteins, facilitating stabilization of lipid rafts. Critically, galectin-4 exerts favourable or unfavourable effects depending upon the cancer. Here we report the first X-ray crystallographic structural information on human galectin-4, specifically the C-terminal carbohydrate recognition domain of human (galectin-4C) in complex with lactose, lactose-3'-sulfate, 2'-fucosyllactose, lacto-N-tetraose and lacto-N-neotetraose. These structures enable elucidation of galectin-4C binding fine-specificity towards sulfated and non-sulfated lacto- and neolacto-series sphingolipids as well as to human blood group antigens. Analysis of the lactose-3'-sulfate complex structure shows that galectin-4C does not recognize the sulfate group using any specific amino acid, but binds the ligand nonetheless. Complex structures with lacto-N-tetraose and lacto-N-neotetraose displayed differences in binding interactions exhibited by the non-reducing-end galactose. That of lacto-N-tetraose points outward from the protein surface whereas that of lacto-N-neotetraose interacts directly with the protein. Recognition patterns of human galectin-4C towards lacto- and neolacto-series glycosphingolipids are similar to those of human galectin-3; however, detailed scrutiny revealed differences stemming from the extended binding site that offer distinction in ligand profiles of these two galectins. Structural characterization of the complex with 2'-fucosyllactose, a carbohydrate with similarity to the H antigen, and molecular dynamics studies highlight structural features that allow specific recognition of A and B antigens, whilst a lack of interaction with the 2'-fucose of blood group antigens was revealed. 4YLZ, 4YM0, 4YM1, 4YM2, 4YM3. © 2015 FEBS.

Humoral markers of active Epstein-Barr virus infection associate with anti-extractable nuclear antigen autoantibodies and plasma galectin-3 binding protein in systemic lupus erythematosus.

PubMed

Rasmussen, N S; Nielsen, C T; Houen, G; Jacobsen, S

2016-12-01

We investigated if signs of active Epstein-Barr virus and cytomegalovirus infections associate with certain autoantibodies and a marker of type I interferon activity in patients with systemic lupus erythematosus. IgM and IgG plasma levels against Epstein-Barr virus early antigen diffuse and cytomegalovirus pp52 were applied as humoral markers of ongoing/recently active Epstein-Barr virus and cytomegalovirus infections, respectively. Plasma galectin-3 binding protein served as a surrogate marker of type I interferon activity. The measurements were conducted in 57 systemic lupus erythematosus patients and 29 healthy controls using ELISAs. Regression analyses and univariate comparisons were performed for associative evaluation between virus serology, plasma galectin-3 binding protein and autoantibodies, along with other clinical and demographic parameters. Plasma galectin-3 binding protein concentrations were significantly higher in systemic lupus erythematosus patients (P = 0.009) and associated positively with Epstein-Barr virus early antigen diffuse-directed antibodies and the presence of autoantibodies against extractable nuclear antigens in adjusted linear regressions (B = 2.02 and 2.02, P = 0.02 and P = 0.002, respectively). Furthermore, systemic lupus erythematosus patients with anti-extractable nuclear antigens had significantly higher antibody levels against Epstein-Barr virus early antigen diffuse (P = 0.02). Our study supports a link between active Epstein-Barr virus infections, positivity for anti-extractable nuclear antigens and increased plasma galectin-3 binding protein concentrations/type I interferon activity in systemic lupus erythematosus patients. © The Author(s) 2016.

Galectin-9 binds to O-glycans on protein disulfide isomerase.

PubMed

Schaefer, Katrin; Webb, Nicholas E; Pang, Mabel; Hernandez-Davies, Jenny E; Lee, Katharine P; Gonzalez, Pascual; Douglass, Martin V; Lee, Benhur; Baum, Linda G

2017-09-01

Changes in the T cell surface redox environment regulate critical cell functions, such as cell migration, viral entry and cytokine production. Cell surface protein disulfide isomerase (PDI) contributes to the regulation of T cell surface redox status. Cell surface PDI can be released into the extracellular milieu or can be internalized by T cells. We have found that galectin-9, a soluble lectin expressed by T cells, endothelial cells and dendritic cells, binds to and retains PDI on the cell surface. While endogenous galectin-9 is not required for basal cell surface PDI expression, exogenous galectin-9 mediated retention of cell surface PDI shifted the disulfide/thiol equilibrium on the T cell surface. O-glycans on PDI are required for galectin-9 binding, and PDI recognition appears to be specific for galectin-9, as galectin-1 and galectin-3 do not bind PDI. Galectin-9 is widely expressed by immune and endothelial cells in inflamed tissues, suggesting that T cells would be exposed to abundant galectin-9, in cis and in trans, in infectious or autoimmune conditions. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Human chimera-type galectin-3: defining the critical tail length for high-affinity glycoprotein/cell surface binding and functional competition with galectin-1 in neuroblastoma cell growth regulation.

PubMed

Kopitz, Jürgen; Vértesy, Sabine; André, Sabine; Fiedler, Sabine; Schnölzer, Martina; Gabius, Hans-Joachim

2014-09-01

Many human proteins have a modular design with receptor and structural domains. Using adhesion/growth-regulatory galectin-3 as model, we describe an interdisciplinary strategy to define the functional significance of its tail established by nine non-triple helical collagen-like repeats (I-IX) and the N-terminal peptide. Genetic engineering with sophisticated mass spectrometric product analysis provided the tools for biotesting, i.e. eight protein variants with different degrees of tail truncation. Evidently,various aspects of galectin-3 activity (cis binding and cell bridging) are affected by tail shortening in a different manner. Thus, this combined approach reveals an unsuspected complexity of structure-function relationship, encouraging further application beyond this chimera-type galectin. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Human milk galectin-3 binding protein and breast-feeding-associated HIV transmission.

PubMed

Chan, Christina S; Kim, Hae-Young; Autran, Chloe; Kim, Jae H; Sinkala, Moses; Kankasa, Chipepo; Mwiya, Mwiya; Thea, Donald M; Aldrovandi, Grace M; Kuhn, Louise; Bode, Lars

2013-12-01

Analysis of milk from 247 HIV-infected Zambian mothers showed that galectin-3 binding protein concentrations were significantly higher among HIV-infected mothers who transmitted HIV through breast-feeding (6.51 ± 2.12 μg/mL) than among nontransmitters but were also correlated with higher milk and plasma HIV RNA copies/mL and lower CD4+ cell counts. The association between galectin-3 binding protein and postnatal transmission was attenuated after adjustment for milk and plasma HIV load and CD4+ cell counts. This suggests that although milk galectin-3 binding protein is a marker of advanced maternal disease, it does not independently modify transmission risk.

Epigenetic Regulation of Galectin-3 Expression by β1 Integrins Promotes Cell Adhesion and Migration*

PubMed Central

Margadant, Coert; van den Bout, Iman; van Boxtel, Antonius L.; Thijssen, Victor L.; Sonnenberg, Arnoud

2012-01-01

Introduction of the integrin β1- but not the β3-subunit in GE11 cells induces an epithelial-to-mesenchymal-transition (EMT)-like phenomenon that is characterized by the loss of cell-cell contacts, cell scattering, increased cell migration and RhoA activity, and fibronectin fibrillogenesis. Because galactose-binding lectins (galectins) have been implicated in these phenomena, we investigated whether galectins are involved in the β1-induced phenotype. We examined 9 galectins and, intriguingly, found that the expression of galectin-3 (Gal-3) is specifically induced by β1 but not by β3. Using β1-β3 chimeric integrins, we show that the induction of Gal-3 expression requires the hypervariable region in the extracellular domain of β1, but not its cytoplasmic tail. Furthermore, Gal-3 expression does not depend on RhoA signaling, serum factors, or any of the major signal transduction pathways involving protein kinase C (PKC), p38 mitogen-activated protein kinase (p38MAPK), extracellular signal-regulated kinase-1/-2 (ERK-1/2), phosphatidylinositol-3-OH kinase (PI3-K), or Src kinases. Instead, Gal-3 expression is controlled in an epigenetic manner. Whereas DNA methylation of the Lgals3 promoter maintains Gal-3 silencing in GE11 cells, expression of β1 causes its demethylation, leading to transcriptional activation of the Lgals3 gene. In turn, Gal-3 expression enhances β1 integrin-mediated cell adhesion to fibronectin (FN) and laminin (LN), as well as cell migration. Gal-3 also promotes β1-mediated cell adhesion to LN and Collagen-1 (Col)-1 in cells that endogenously express Gal-3 and β1 integrins. In conclusion, we identify a functional feedback-loop between β1 integrins and Gal-3 that involves the epigenetic induction of Gal-3 expression during integrin-induced EMT and cell scattering. PMID:23118221

Regulation of Eosinophil Recruitment and Activation by Galectins in Allergic Asthma.

PubMed

Rao, Savita P; Ge, Xiao Na; Sriramarao, P

2017-01-01

Eosinophils are differentiated granulocytes that are recruited from the bone marrow to sites of inflammation via the vascular system. Allergic asthma is characterized by the presence of large numbers of eosinophils in the lungs and airways. Due to their capacity to rapidly release inflammatory mediators such as cytokines, chemokines, growth factors, and cytotoxic granule proteins upon stimulation, eosinophils play a critical role in pro-inflammatory processes in allergen-exposed lungs. Identifying key players and understanding the molecular mechanisms directing eosinophil trafficking and recruitment to inflamed airways is a key to developing therapeutic strategies to limit their influx. Recent studies have brought to light the important role of glycans and glycan binding proteins in regulating recruitment of eosinophils. In addition to the role of previously identified eosinophil- and endothelial-expressed adhesion molecules in mediating eosinophil trafficking and recruitment to the inflamed airways, studies have also indicated a role for galectins (galectin-3) in this process. Galectins are mammalian lectins expressed by various cell types including eosinophils. Intracellularly, they can regulate biological processes such as cell motility. Extracellularly, galectins interact with β-galactosides in cell surface-expressed glycans to regulate cellular responses like production of inflammatory mediators, cell adhesion, migration, and apoptosis. Eosinophils express galectins intracellularly or on the cell surface where they interact with cell surface glycoconjugate receptors. Depending on the type (galectin-1, -3, etc.) and location (extracellular or intracellular, endogenous or exogenously delivered), galectins differentially regulate eosinophil recruitment, activation, and apoptosis and thus exert a pro- or anti-inflammatory outcome. Here, we have reviewed information pertaining to galectins (galectin-1, -3 -9, and -10) that are expressed by eosinophils themselves and/or other cells that play a role in eosinophil recruitment and function in the context of allergic asthma and their potential use as disease biomarkers or therapeutic targets for immunomodulation.

Galectin-3: A Friend but Not a Foe during Trypanosoma cruzi Experimental Infection.

PubMed

da Silva, Aline A; Teixeira, Thaise L; Teixeira, Samuel C; Machado, Fabrício C; Dos Santos, Marlus A; Tomiosso, Tatiana C; Tavares, Paula C B; Brígido, Rebecca T E Silva; Martins, Flávia Alves; Silva, Nadjania S de Lira; Rodrigues, Cassiano C; Roque-Barreira, Maria C; Mortara, Renato A; Lopes, Daiana S; Ávila, Veridiana de Melo Rodrigues; da Silva, Claudio V

2017-01-01

Trypanosoma cruzi interacts with host cells, including cardiomyocytes, and induces the production of cytokines, chemokines, metalloproteinases, and glycan-binding proteins. Among the glycan-binding proteins is Galectin-3 (Gal-3), which is upregulated after T. cruzi infection. Gal-3 is a member of the lectin family with affinity for β-galactose containing molecules; it can be found in both the nucleus and the cytoplasm and can be either membrane-associated or secreted. This lectin is involved in several immunoregulatory and parasite infection process. Here, we explored the consequences of Gal-3 deficiency during acute and chronic T. cruzi experimental infection. Our results demonstrated that lack of Gal-3 enhanced in vitro replication of intracellular parasites, increased in vivo systemic parasitaemia, and reduced leukocyte recruitment. Moreover, we observed decreased secretion of pro-inflammatory cytokines in spleen and heart of infected Gal-3 knockout mice. Lack of Gal-3 also led to elevated mast cell recruitment and fibrosis of heart tissue. In conclusion, galectin-3 expression plays a pivotal role in controlling T. cruzi infection, preventing heart damage and fibrosis.

Chronic upregulation of activated microglia immunoreactive for galectin-3/Mac-2 and nerve growth factor following diffuse axonal injury

PubMed Central

2010-01-01

Background Diffuse axonal injury in patients with traumatic brain injury (TBI) can be associated with morbidity ranging from cognitive difficulties to coma. Magnetic resonance imaging scans now allow early detection of axonal injury following TBI, and have linked cognitive disability in these patients to white matter signal changes. However, little is known about the pathophysiology of this white matter injury, and the role of microglial activation in this process. It is increasingly recognized that microglia constitute a heterogeneous population with diverse roles following injury. In the present studies, we tested the hypothesis that following diffuse axonal injury involving the corpus callosum, there is upregulation of a subpopulation of microglia that express the lectin galectin-3/Mac-2 and are involved in myelin phagocytosis. Methods Adult mice were subject to midline closed skull injury or sham operation and were sacrificed 1, 8, 14 or 28 days later. Immunohistochemistry and immunofluorescence techniques were used to analyze patterns of labelling within the corpus callosum qualitatively and quantitatively. Results Activated microglia immunoreactive for galectin-3/Mac-2 were most abundant 1 day following injury. Their levels were attenuated at later time points after TBI but still were significantly elevated compared to sham animals. Furthermore, the majority of galectin-3/Mac-2+ microglia were immunoreactive for nerve growth factor in both sham and injured animals. Conclusions Our results suggest that galectin-3/Mac-2+ microglia play an important role in the pathogenesis of diffuse axonal injury both acutely and chronically and that they mediate their effects, at least in part by releasing nerve growth factor. PMID:20507613

Galectins are human milk glycan receptors

PubMed Central

Noll, Alexander J; Gourdine, Jean-Philippe; Yu, Ying; Lasanajak, Yi; Smith, David F; Cummings, Richard D

2016-01-01

The biological recognition of human milk glycans (HMGs) is poorly understood. Because HMGs are rich in galactose we explored whether they might interact with human galectins, which bind galactose-containing glycans and are highly expressed in epithelial cells and other cell types. We screened a number of human galectins for their binding to HMGs on a shotgun glycan microarray consisting of 247 HMGs derived from human milk, as well as to a defined HMG microarray. Recombinant human galectins (hGal)-1, -3, -4, -7, -8 and -9 bound selectively to glycans, with each galectin recognizing a relatively unique binding motif; by contrast hGal-2 did not recognize HMGs, but did bind to the human blood group A Type 2 determinants on other microarrays. Unlike other galectins, hGal-7 preferentially bound to glycans expressing a terminal Type 1 (Galβ1-3GlcNAc) sequence, a motif that had eluded detection on non-HMG glycan microarrays. Interactions with HMGs were confirmed in a solution setting by isothermal titration microcalorimetry and hapten inhibition experiments. These results demonstrate that galectins selectively bind to HMGs and suggest the possibility that galectin–HMG interactions may play a role in infant immunity. PMID:26747425

PSC-derived Galectin-1 inducing epithelial-mesenchymal transition of pancreatic ductal adenocarcinoma cells by activating the NF-κB pathway

PubMed Central

Tang, Dong; Zhang, Jingqiu; Yuan, Zhongxu; Zhang, Hongpeng; Chong, Yang; Huang, Yuqin; Wang, Jie; Xiong, Qingquan; Wang, Sen; Wu, Qi; Tian, Ying; Lu, Yongdie; Ge, Xiao; Shen, Wenjing; Wang, Daorong

2017-01-01

Galectin-1 has previously been shown to be strongly expressed in activated pancreatic stellate cells (PSCs) and promote the development and metastasis of pancreatic ductal adenocarcinoma (PDAC). However, the molecular mechanisms by which Galectin-1 promotes the malignant behavior of pancreatic cancer cells remain unclear. In this study, we examined the effects of Galectin-1 knockdown or overexpression in PSCs co-cultured with pancreatic cancer (PANC-1) cells. Immunohistochemical analysis showed expression of epithelial-mesenchymal transition (EMT) markers and MMP9 were positively associated with the expression of Galectin-1 in 66 human PDAC tissues. In addition, our in vitro studies showed PSC-derived Galectin-1 promoted the proliferation, invasion, and survival (anti-apoptotic effects) of PANC-1 cells. We also showed PSC-derived Galectin-1 induced EMT of PANC-1 cells and activated the NF-кB pathway in vitro. Our mixed (PSCs and PANC-1 cells) mouse orthotopic xenograft model indicated that overexpression of Galectin-1 in PSCs significantly promoted the proliferation, growth, invasion, and liver metastasis of the transplanted tumor. Moreover, Galectin-1 overexpression in PSCs was strongly associated with increased expression of EMT markers in both the orthotopic xenograft tumor in the pancreas and in metastatic lesions of naked mice. We conclude that PSC-derived Galectin-1 promotes the malignant behavior of PDAC by inducing EMT via activation of the NF-κB pathway. Our results suggest that targeting Galectin-1 in PSCs could represent a promising therapeutic strategy for PDAC progression and metastasis. PMID:29156810

Analytical evaluation of the automated galectin-3 assay on the Abbott ARCHITECT immunoassay instruments.

PubMed

Gaze, David C; Prante, Christian; Dreier, Jens; Knabbe, Cornelius; Collet, Corinne; Launay, Jean-Marie; Franekova, Janka; Jabor, Antonin; Lennartz, Lieselotte; Shih, Jessie; del Rey, Jose Manuel; Zaninotto, Martina; Plebani, Mario; Collinson, Paul O

2014-06-01

Galectin-3 is secreted from macrophages and binds and activates fibroblasts forming collagen. Tissue fibrosis is central to the progression of chronic heart failure (CHF). We performed a European multicentered evaluation of the analytical performance of the two-step routine and Short Turn-Around-Time (STAT) galectin-3 immunoassay on the ARCHITECT i1000SR, i2000SR, and i4000SR (Abbott Laboratories). We evaluated the assay precision and dilution linearity for both routine and STAT assays and compared serum and plasma, and fresh vs. frozen samples. The reference interval and biological variability were also assessed. Measurable samples were compared between ARCHITECT instruments and between the routine and STAT assays and also to a galectin-3 ELISA (BG Medicine). The total assay coefficient of variation (CV%) was 2.3%-6.2% and 1.7%-7.4% for the routine and STAT assays, respectively. Both assays demonstrated linearity up to 120 ng/mL. Galectin-3 concentrations were higher in plasma samples than in serum samples and correlated well between fresh and frozen samples (R=0.997), between the routine and STAT assays, between the ARCHITECT i1000 and i2000 instruments and with the galectin-3 ELISA. The reference interval on 627 apparently healthy individuals (53% male) yielded upper 95th and 97.5th percentiles of 25.2 and 28.4 ng/mL, respectively. Values were significantly lower in subjects younger than 50 years. The galectin-3 routine and STAT assays on the Abbott ARCHITECT instruments demonstrated good analytical performance. Further clinical studies are required to demonstrate the diagnostic and prognostic potential of this novel marker in patients with CHF.

Peripheral blood TIM-3 positive NK and CD8+ T cells throughout pregnancy: TIM-3/galectin-9 interaction and its possible role during pregnancy.

PubMed

Meggyes, Matyas; Miko, Eva; Polgar, Beata; Bogar, Barbara; Farkas, Balint; Illes, Zsolt; Szereday, Laszlo

2014-01-01

The T-cell immunoglobulin and mucin domain (TIM) family is a relatively newly described group of molecules with a conserved structure and important immunological functions. Identification of Galectin-9 as a ligand for TIM-3 has established the Galectin-9/TIM-3 pathway as an important negative regulator of Th1 immunity and tolerance induction. Data about the TIM-3/Gal-9 pathway in the pathogenesis of human diseases is emerging, but their possible role during human pregnancy is not precisely known. The aim of our study was to investigate the number, phenotype and functional activity of TIM-3+ peripheral blood mononuclear cells during healthy human pregnancy. 57 healthy pregnant women [first trimester (n = 16); second trimester (n = 19); third trimester (n = 22)] and 30 non-pregnant controls were enrolled in the study. We measured the surface expression of TIM-3 by cytotoxic T cells, NK cells and NK cell subsets as well as Galectin-9 expression by regulatory T cells by flow cytometry. We analyzed the cytokine production and cytotoxicity of TIM3+ and TIM3- CD8 T and NK cells obtained from non-pregnant and healthy pregnant women at different stages of pregnancy by flow cytometry. Serum Galectin-9 levels were measured by ELISA. Our results show that the numbers of peripheral NK and cytotoxic T cells and their TIM-3 expression do not change between the first, second and third trimesters of pregnancy. Compared to non-pregnant individuals, regulatory T cells show higher level of Galectin-9 expression as pregnancy proceeds, which is in line with the level of Galectin-9 in the patients sera. Cytotoxic T cells, NK cells and NK cell subsets expressing TIM-3 molecule show altered cytokine production and cytotoxicity during pregnancy compared to non-pregnant individuals. Our results indicate that Galectin-9 expressing regulatory T cells, TIM-3+ cytotoxic T cells and NK cells could play an important role in the maintenance of healthy pregnancy.

The Cek1‑mediated MAP kinase pathway regulates exposure of α‑1,2 and β‑1,2‑mannosides in the cell wall of Candida albicans modulating immune recognition.

PubMed

Román, E; Correia, I; Salazin, A; Fradin, C; Jouault, T; Poulain, D; Liu, F-T; Pla, J

2016-07-03

The Cek1 MAP kinase (MAPK) mediates vegetative growth and cell wall biogenesis in the fungal pathogen Candida albicans. Alterations in the fungal cell wall caused by a defective Cek1‑mediated signaling pathway leads to increased β‑1,3‑glucan exposure influencing dectin‑1 fungal recognition by immune cells. We show here that cek1 cells also display an increased exposure of α‑1,2 and β‑1,2‑mannosides (α‑M and β‑M), a phenotype shared by strains defective in the activating MAPKK Hst7, suggesting a general defect in cell wall assembly. cek1 cells display walls with loosely bound material as revealed by transmission electron microscopy and are sensitive to tunicamycin, an inhibitor of N‑glycosylation. Transcriptomal analysis of tunicamycin treated cells revealed a differential pattern between cek1 and wild type cells which involved mainly cell wall and stress related genes. Mapping α‑M and β‑M epitopes in the mannoproteins of different cell wall fractions (CWMP) revealed an important shift in the molecular weight of the mannan derived from mutants defective in this MAPK pathway. We have also assessed the role of galectin‑3, a member of a β‑galactoside‑binding protein family shown to bind to and kill C. albicans through β‑M recognition, in the infection caused by cek1 mutants. Increased binding of cek1 to murine macrophages was shown to be partially blocked by lactose. Galectin-3(-/-) mice showed increased resistance to fungal infection, although galectin-3 did not account for the reduced virulence of cek1 mutants in a mouse model of systemic infection. All these data support a role for the Cek1‑mediated pathway in fungal cell wall maintenance, virulence and antifungal discovery.

β4-Integrin/PI3K Signaling Promotes Tumor Progression through the Galectin-3-N-Glycan Complex.

PubMed

Kariya, Yukiko; Oyama, Midori; Hashimoto, Yasuhiro; Gu, Jianguo; Kariya, Yoshinobu

2018-06-01

Malignant transformation is associated with aberrant N -glycosylation, but the role of protein N -glycosylation in cancer progression remains poorly defined. β4-integrin is a major carrier of N -glycans and is associated with poor prognosis, tumorigenesis, and metastasis. Here, N -glycosylation of β4-integrin contributes to the activation of signaling pathways that promote β4-dependent tumor development and progression. Increased expression of β1,6GlcNAc-branched N -glycans was found to be colocalized with β4-integrin in human cutaneous squamous cell carcinoma tissues, and that the β1,6GlcNAc residue was abundant on β4-integrin in transformed keratinocytes. Interruption of β1,6GlcNAc-branching formation on β4-integrin with the introduction of bisecting GlcNAc by N -acetylglucosaminyltransferase III overexpression was correlated with suppression of cancer cell migration and tumorigenesis. N -Glycan deletion on β4-integrin impaired β4-dependent cancer cell migration, invasion, and growth in vitro and diminished tumorigenesis and proliferation in vivo The reduced abilities of β4-integrin were accompanied with decreased phosphoinositol-3 kinase (PI3K)/Akt signals and were restored by the overexpression of the constitutively active p110 PI3K subunit. Binding of galectin-3 to β4-integrin via β1,6GlcNAc-branched N -glycans promoted β4-integrin-mediated cancer cell adhesion and migration. In contrast, a neutralizing antibody against galectin-3 attenuated β4-integrin N -glycan-mediated PI3K activation and inhibited the ability of β4-integrin to promote cell motility. Furthermore, galectin-3 knockdown by shRNA suppressed β4-integrin N -glycan-mediated tumorigenesis. These findings provide a novel role for N -glycosylation of β4-integrin in tumor development and progression, and the regulatory mechanism for β4-integrin/PI3K signaling via the galectin-3- N -glycan complex. Implications: N -Glycosylation of β4-integrin plays a functional role in promoting tumor development and progression through PI3K activation via the galectin-3- N -glycan complex. Mol Cancer Res; 16(6); 1024-34. ©2018 AACR . ©2018 American Association for Cancer Research.

Interaction of the B cell-specific transcriptional coactivator OCA-B and galectin-1 and a possible role in regulating BCR-mediated B cell proliferation.

PubMed

Yu, Xin; Siegel, Rachael; Roeder, Robert G

2006-06-02

OCA-B is a B cell-specific transcriptional coactivator for OCT factors during the activation of immunoglobulin genes. In addition, OCA-B is crucial for B cell activation and germinal center formation. However, the molecular mechanisms for OCA-B function in these processes are not clear. Our previous studies documented two OCA-B isoforms and suggested a novel mechanism for the function of the myristoylated, membrane-bound form of OCA-B/p35 as a signaling molecule. Here, we report the identification of galectin-1, and related galectins, as a novel OCA-B-interacting protein. The interaction of OCA-B and galectin-1 can be detected both in vivo and in vitro. The galectin-1 binding domain in OCA-B has been localized to the N terminus of OCA-B. In B cells lacking OCA-B expression, increased galectin-1 expression, secretion, and cell surface association are observed. Consistent with these observations, and a reported inhibitory interaction of galectin-1 with CD45, the phosphatase activity of CD45 is reduced modestly, but significantly, in OCA-B-deficient B cells. Finally, galectin-1 is shown to negatively regulate B cell proliferation and tyrosine phosphorylation upon BCR stimulation. Together, these results raise the possibility that OCA-B may regulate BCR signaling through an association with galectin-1.

Galectin-3 enhances angiogenic and migratory potential of microglial cells via modulation of integrin linked kinase signaling

PubMed Central

Wesley, Umadevi V.; Vemuganti, Raghu; Ayvaci, Rabia; Dempsey, Robert J.

2013-01-01

Focal cerebral ischemia initiates self-repair mechanisms that include the production of neurotrophic factors and cytokines. Galectin-3 is an important angiogenic cytokine. We have previously demonstrated that expression of galectin 3 (Gal-3), a carbohydrate binding protein is significantly upregulated in activated microglia in the brains of rats subjected to focal ischemia. Further blocking of Gal-3 function with Gal-3 neutralizing antibody decreased the microvessel density in ischemic brain. We currently show that Gal-3 significantly increases the viability of microglia BV2 cells subjected to oxygen glucose deprivation (OGD) and re-oxygenation. Exogenous Gal-3 promoted the formation of pro-angiogenic structures in an in vitro human umbilical vein endothelial (HUVEC) and BV2 cell co-culture model. Gal-3 induced angiogenesis was associated with increased expression of vascular endothelial growth factor. The conditioned medium of BV2 cells exposed to OGD contained increased Gal-3 levels, and promoted the formation of pro-angiogenic structures in an in vitro HUVEC culture model. Gal-3 also augmented the in vitro migratory potential of BV2 microglia. Gal-3 mediated functions were associated with increased levels of integrin-linked kinase (ILK) signaling as demonstrated by the impaired angiogenesis and migration of BV2 cells following targeted silencing of ILK expression by SiRNA. Furthermore, we show that ILK levels correlate with the levels of phos-AKT and ERK1/2 that are downstream effectors of ILK pathway. Taken together, our studies indicate that Gal-3 contributes to angiogenesis and microglia migration that may have implications in post stroke repair. PMID:23246924

Galectins expressed differently in genetically susceptible C57BL/6 and resistant BALB/c mice during acute ocular Toxoplasma gondii infection.

PubMed

Chen, S-J; Zhang, Y-X; Huang, S-G; Lu, F-L

2017-07-01

Ocular toxoplasmosis (OT) caused by Toxoplasma gondii is a major cause of infectious uveitis, however little is known about its immunopathological mechanism. Susceptible C57BL/6 (B6) and resistant BALB/c mice were intravitreally infected with 500 tachyzoites of the RH strain of T. gondii. B6 mice showed more severe ocular pathology and higher parasite loads in the eyes. The levels of galectin (Gal)-9 and its receptors (Tim-3 and CD137), interferon (IFN)-γ, IL-6 and IL-10 were significantly higher in the eyes of B6 mice than those of BALB/c mice; however, the levels of IFN-α and -β were significantly decreased in the eyes and CLNs of B6 mice but significantly increased in BALB/c mice after infection. After blockage of galectin-receptor interactions by α-lactose, neither ocular immunopathology nor parasite loads were different from those of infected BALB/c mice without α-lactose treatment. Although the expressions of Gal-9/receptor were significantly increased in B6 mice and Gal-1 and -3 were upregulated in both strains of mice upon ocular T. gondii infection, blockage of galectins did not change the ocular pathogenesis of genetic resistant BALB/c mice. However, IFN-α and -β were differently expressed in B6 and BALB/c mice, suggesting that type I IFNs may play a protective role in experimental OT.

Galectins and Carcinogenesis: Their Role in Head and Neck Carcinomas and Thyroid Carcinomas.

PubMed

Kindt, Nadège; Journe, Fabrice; Ghanem, Ghanem E; Saussez, Sven

2017-12-18

Head and neck cancers are among the most frequently occurring cancers worldwide. Of the molecular drivers described for these tumors, galectins play an important role via their interaction with several intracellular pathways. In this review, we will detail and discuss this role with specific reference to galectins-1, -3, and -7 in angiogenesis, cell proliferation, and invasion as well as in cell transformation and cancer progression. Furthermore, we will evaluate the prognostic value of galectin expression in head and neck cancers including those with oral cavity, salivary gland, and nasopharyngeal pathologies. In addition, we will discuss the involvement of these galectins in thyroid cancers where their altered expression is proposed as a new diagnostic biomarker.

The prognostic value of sST2 and galectin-3 considering different aetiologies in non-ischaemic heart failure.

PubMed

Binas, David; Daniel, Hanna; Richter, Anette; Ruppert, Volker; Schlüter, Klaus-Dieter; Schieffer, Bernhard; Pankuweit, Sabine

2018-01-01

Several studies indicate a prognostic value of sST2 and galectin-3 in heart failure (HF). While previous studies focused on ischaemic cause of HF, we investigated the role of sST2 and galectin-3 in patients with non-ischaemic dilated cardiomyopathy (DCM). sST2 and galectin-3 serum concentrations were measured in 262 subjects with DCM. Survival rates were determined for all-cause mortality (ACM) and cardiac mortality (CM). In a univariate model, sST2 as a continuous variable was a predictor of ACM (HR 1.05; 95% CI 1.03 to 1.07, P<0.001) and CM (HR 1.03; 95% CI 1.00 to 1.06, P=0.040). In the subgroup of patients with inflammatory and/or viral DCM (DCMi⋎viral), the endpoints ACM (HR 1.10; 95% CI 1.05 to 1.17, P<0.001) and CM (HR 1.10; 95% CI 1.02 to 1.18, P=0.013) were significant. In the subgroup of patients with idiopathic DCM, the endpoint ACM (HR 1.04; 95% CI 1.01 to 1.07, P=0.019) was significant. In a multivariate model, the prognostic value of the sST2 main group remained intact for ACM (HR 1.04; 95% CI 1.02 to 1.07, P=0.003).Univariate and multivariate analysis of galectin-3 as continuous variable did not show any significant result. However, in a quartile model, intermediate values of galectin-3 were significantly associated with a lower event rate of ACM and CM. The study revealed that sST2 predicts ACM and CM in patients with non-ischaemic HF and could be useful especially in patients with inflammatory background. Our findings that intermediate levels of galectin-3 allow for better prognosis were new and different to other investigations. NCT03090425; Results.

Distinction between papillary thyroid hyperplasia and papillary thyroid carcinoma by immunohistochemical staining for cytokeratin 19, galectin-3, and HBME-1.

PubMed

Casey, Mary B; Lohse, Christine M; Lloyd, Ricardo V

2003-01-01

The histopathology of papillary thyroid hyperplasia and papillary thyroid carcinoma is similar enough to cause a diagnostic dilemma in a few cases. Both lesions may have papillary fronds with fibrovascular cores, nuclear crowding, and nuclear anisocytosis. Formalin- fixed paraffin-embedded tissues from 30 randomly selected patients with papillary thyroid hyperplasia and an equal number from patients with papillary thyroid carcinoma were analyzed for expression of cytokeratin 19 (CK19), galectin-3, and HBME-1. Cases of papillary thyroid carcinoma had moderate to strong CK19, galectin-3, and HBME-1 reactivity although both CK19 and galectin-3 showed positive staining in a significant number of nonneoplastic thyroid cases. HBME-1 was uncommon in the nonneoplastic cases. These results indicate that HBME-1 may be useful in helping to distinguish papillary thyroid carcinoma from hyperplasia in diagnostically difficult cases.

Higher expression of galectin-3 and galectin-9 in periapical granulomas than in radicular cysts and an increased toll-like receptor-2 and toll-like receptor-4 expression are associated with reactivation of periapical inflammation.

PubMed

de Oliveira, Rita de Cássia Medeiros; Beghini, Marcela; Borges, Cláudia Renata Bibiano; Alves, Polyanna Miranda; de Araújo, Marcelo Sivieri; Pereira, Sanívia Aparecida de Lima; Rodrigues, Virmondes; Rodrigues, Denise Bertulucci Rocha

2014-02-01

Cysts and periapical granulomas are inflammatory reactions that develop in response to periapical infection by microbial species in dental root canal. It is known that toll-like receptors (TLRs) are pathogen recognition molecules and that galectins are lectins that can be associated with the inflammatory process, stimulating or inhibiting the immune system. The objective of this study was to evaluate the in situ expression of TLRs and galectins in radicular cysts and periapical granulomas. We analyzed 62 cases (30 radicular cysts, 27 periapical granulomas, and 5 control cases). Indirect immunohistochemistry was used to evaluate the expression of TLRs (TRL-2 and TLR-4) and galectins (Gal-3 and Gal-9). The expression of Gal-3 and Gal-9 was significantly higher in periapical granulomas and radicular cysts than in the control group. Similarly, both Gal-3 and Gal-9 were expressed significantly more in periapical granulomas than in radicular cysts. The expression of TLR-2 was significantly higher in periapical granulomas and radicular cysts than in the control group, and it was also significantly higher in radicular cysts with sinus tract than in the cases without sinus tract. Furthermore, the expression of TLR-4 was significantly higher in the cases of periapical granulomas with sinus tract than in the cases without sinus tract. Gal-3/Gal-9 and TLR-2/TLR-4 expression in the periapical granulomas and radicular cysts is associated with reactive periapical inflammation. Pathobiology of periapical disease is a very complex interplay of many bioactive molecules involved in immunoinflammatory responses. Up-regulation of these bioactive molecules might be an important modulator of inflammatory periapical lesions. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Combining Crystallography and Hydrogen-Deuterium Exchange to Study Galectin-Ligand Complexes.

PubMed

Ruiz, Federico M; Gilles, Ulrich; Lindner, Ingo; André, Sabine; Romero, Antonio; Reusch, Dietmar; Gabius, Hans-Joachim

2015-09-21

The physiological significance arising from translating information stored in glycans into cellular effects explains the interest in structurally defining lectin-carbohydrate recognition. The relatively small set of adhesion/growth-regulatory galectins in chicken makes this system attractive to study the origins of specificity and divergence. Cell binding by using glycosylation mutants reveals binding of the N-terminal domain of chicken galectin-8 (CG-8N) to α-2,3-sialylated and galactose-terminated glycan chains. Cocrystals with lactose and its 3'-sialylated derivative disclose Arg58 as a key contact for the carboxylic acid and differences in loop lengths to the three homodimeric chicken galectins. Monitoring hydrogen-deuterium exchange by mass spectrometry revealed an effective reduction of deuteration after ligand binding within the contact area. In addition, evidence for changes in solvent accessibility of amide protons beyond this site was obtained. Their detection, which highlights the sensor capacity of this technique, encourages systematic studies on galectins and beyond. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High Expression of Galectin-3 in Patients with IgG4-Related Disease: A Proteomic Approach.

PubMed

Salah, Adeeb; Yoshifuji, Hajime; Ito, Shinji; Kitagori, Koji; Kiso, Kaori; Yamada, Norishige; Nakajima, Toshiki; Haga, Hironori; Tsuruyama, Tatsuaki; Miyagawa-Hayashino, Aya

2017-01-01

Immunoglobulin G4-related disease (IgG4-RD) is a multiorgan condition manifesting itself in different forms. This study aimed to investigate protein expression profiles and to find the possible biomarker for IgG4-RD by liquid chromatography mass spectrometry (LC-MS) using tissue sections in IgG4-RD patients. Protein expression profiles in five IgG4-related pancreatitis and three normal pancreatic samples were compared using LC-MS and were validated by quantitative real-time PCR (qRT-PCR), immunoblotting, and immunohistochemistry. ELISA was employed in the serum of 20 patients with systemic IgG4-RD before and during steroid treatment. LC-MS indicated that the levels of 17 proteins were significantly higher and 12 others were significantly lower in IgG4-related pancreatitis patients compared to controls. Among these proteins, galectin-3 levels were 13-fold higher in IgG4-related pancreatitis ( P < 0.01). These results were confirmed by immunoblotting and qRT-PCR. The average number of galectin-3 + cells in various organs of IgG4-RD patients, including salivary glands, lungs, and lymph nodes, was higher than in controls. Galectin-3 was detectable in macrophages, dendritic cells, and stromal myofibroblast-like cells, but not in lymphocytes by immunofluorescence staining. Serum galectin-3 levels were higher in patients with IgG4-RD compared with healthy donors and remained high during steroid therapy. Galectin-3 was overexpressed in IgG4-RD and the levels were indirectly related to clinical activity.

High Expression of Galectin-3 in Patients with IgG4-Related Disease: A Proteomic Approach

PubMed Central

Salah, Adeeb; Yoshifuji, Hajime; Ito, Shinji; Kitagori, Koji; Kiso, Kaori; Yamada, Norishige; Nakajima, Toshiki; Haga, Hironori; Tsuruyama, Tatsuaki

2017-01-01

Objectives Immunoglobulin G4-related disease (IgG4-RD) is a multiorgan condition manifesting itself in different forms. This study aimed to investigate protein expression profiles and to find the possible biomarker for IgG4-RD by liquid chromatography mass spectrometry (LC-MS) using tissue sections in IgG4-RD patients. Methods Protein expression profiles in five IgG4-related pancreatitis and three normal pancreatic samples were compared using LC-MS and were validated by quantitative real-time PCR (qRT-PCR), immunoblotting, and immunohistochemistry. ELISA was employed in the serum of 20 patients with systemic IgG4-RD before and during steroid treatment. Results LC-MS indicated that the levels of 17 proteins were significantly higher and 12 others were significantly lower in IgG4-related pancreatitis patients compared to controls. Among these proteins, galectin-3 levels were 13-fold higher in IgG4-related pancreatitis (P < 0.01). These results were confirmed by immunoblotting and qRT-PCR. The average number of galectin-3 + cells in various organs of IgG4-RD patients, including salivary glands, lungs, and lymph nodes, was higher than in controls. Galectin-3 was detectable in macrophages, dendritic cells, and stromal myofibroblast-like cells, but not in lymphocytes by immunofluorescence staining. Serum galectin-3 levels were higher in patients with IgG4-RD compared with healthy donors and remained high during steroid therapy. Conclusion Galectin-3 was overexpressed in IgG4-RD and the levels were indirectly related to clinical activity. PMID:28593065

The Synthesis of N-Acetyllactosamine Functionalized Dendrimers, and the Functionalization of Silica Surfaces Using Tunable Dendrons and beta-Cyclodextrins

NASA Astrophysics Data System (ADS)

Ennist, Jessica Helen

Galectin-3 is beta-galactoside binding protein which is found in many healthy cells. In cancer, the galectin-3/tumor-associated Thomsen-Friedenreich antigen (TF antigen) interaction has been implicated in heterotypic and homotypic cellular adhesion and apoptotic signaling pathways. However, a stronger mechanistic understanding of the role of galectin-3 in these processes is needed. N-acetyllactosamine (LacNAc) is a non-native ligand for galectin-3 which binds with comparable affinity to the TF antigen and therefore an important ligand to study galectin-3 mediated processes. To study galectin-3 mediated homotypic cellular aggregation, four generations of polyamidoamine (PAMAM) dendrimers were functionalized with N-acetyllactosamine using a four-step chemoenzymatic route. The enzymatic step controlled the regiochemistry of the galactose addition to N-acetylglucosamine functionalized dendrimers using a recombinant beta-1,4-Galactosyltransferase-/UDP-4'-Gal Epimerase Fusion Protein (lgtB-galE). Homotypic cellular aggregation, which is promoted by the presence of galectin-3 as it binds to glycosides at the cell surface, was studied using HT-1080 fibrosarcoma, A549 lung, and DU-145 prostate cancer cell lines. In the presence of small LacNAc functionalized PAMAM dendrimers, galectin-3 induced cancer cellular aggregation was inhibited. However, the larger glycodendrimers induced homotypic cellular aggregation. Additionally, novel poly(aryl ether) dendronized silica surfaces designed for reversible adsorbtion of targeted analytes were synthesized, and characterization using X-ray Photoelectron Spectroscopy (XPS) was performed. Using a Cu(I) mediated cycloaddition "click" reaction, beta-cyclodextrin was appended to dendronized surfaces via triazole formation and also to a non-dendronized surface for comparison purposes. First generation G(1) dendrons have more than 6 times greater capacity to adsorb targeted analytes than slides functionalized with monomeric beta-cyclodextrin and are 2 times greater than slides functionalized with larger generation dendrons. This study reported beta-cyclodextrin functionalized surfaces can undergo a triggered release of the adsorbent, but otherwise retained the targeted analyte through multiple aqueous washes. Therefore, a new generation of G(1) dendronized surfaces capable of reversible adsorption were developed by heterogeneously appending sulfonic acid/pyridine end-groups. Auger Electron Spectroscopy (AES) was used to quantify the ratio of groups installed. Furthermore, G(1) dendronized surfaces were functionalized homogenously with sulfonic acid and pyridine for comparison and with chiral amino acids for chiral recognition studies.

Galectin-3 alters the lateral mobility and clustering of β1-integrin receptors

PubMed Central

Yang, Esther H.; Rode, Julia; Howlader, Md. Amran; Eckermann, Marina; Santos, Jobette T.; Hernandez Armada, Daniel; Zheng, Ruixiang; Zou, Chunxia

2017-01-01

Glycoprotein receptors are influenced by myriad intermolecular interactions at the cell surface. Specific glycan structures may interact with endogenous lectins that enforce or disrupt receptor-receptor interactions. Glycoproteins bound by multivalent lectins may form extended oligomers or lattices, altering the lateral mobility of the receptor and influencing its function through endocytosis or changes in activation. In this study, we have examined the interaction of Galectin-3 (Gal-3), a human lectin, with adhesion receptors. We measured the effect of recombinant Gal-3 added exogenously on the lateral mobility of the α5β1 integrin on HeLa cells. Using single-particle tracking (SPT) we detected increased lateral mobility of the integrin in the presence of Gal-3, while its truncated C-terminal domain (Gal-3C) showed only minor reductions in lateral mobility. Treatment of cells with Gal-3 increased β1-integrin mediated migration with no apparent changes in viability. In contrast, Gal-3C decreased both cell migration and viability. Fluorescence microscopy allowed us to confirm that exogenous Gal-3 resulted in reorganization of the integrin into larger clusters. We used a proteomics analysis to confirm that cells expressed endogenous Gal-3, and found that addition of competitive oligosaccharide ligands for the lectin altered the lateral mobility of the integrin. Together, our results are consistent with a Gal-3–integrin lattice model of binding and confirm that the lateral mobility of integrins is natively regulated, in part, by galectins. PMID:29016609

Galectin-3 as a Potential Target to Prevent Cancer Metastasis

PubMed Central

Ahmed, Hafiz; AlSadek, Dina M. M.

2015-01-01

Interactions between two cells or between cell and extracellular matrix mediated by protein–carbohydrate interactions play pivotal roles in modulating various biological processes such as growth regulation, immune function, cancer metastasis, and apoptosis. Galectin-3, a member of the β-galactoside-binding lectin family, is involved in fibrosis as well as cancer progression and metastasis, but the detailed mechanisms of its functions remain elusive. This review discusses its structure, carbohydrate-binding properties, and involvement in various aspects of tumorigenesis and some potential carbohydrate ligands that are currently investigated to block galectin-3 activity. PMID:26640395

Glycobiology simplified: diverse roles of glycan recognition in inflammation

PubMed Central

Schnaar, Ronald L.

2016-01-01

Glycans and complementary glycan-binding proteins are essential components in the language of cell-cell interactions in immunity. The study of glycan function is the purview of glycobiology, which has often been presented as an unusually complex discipline. In fact, the human glycome, composed of all of its glycans, is built primarily from only 9 building blocks that are combined by enzymes (writers) with specific and limited biosynthetic capabilities into a tractable and increasingly accessible number of potential glycan patterns that are functionally read by several dozen human glycan-binding proteins (readers). Nowhere is the importance of glycan recognition better understood than in infection and immunity, and knowledge in this area has already led to glycan mimetic anti-infective and anti-inflammatory drugs. This review includes a brief tutorial on human glycobiology and a limited number of specific examples of glycan-binding protein-glycan interactions that initiate and regulate inflammation. Examples include representatives from different glycan-binding protein families, including the C-type lectins (E-selectin, P-selectin, dectin-1, and dectin-2), sialic acid-binding immunoglobulin-like lectins (sialic acid-binding immunoglobulin-like lectins 8 and 9), galectins (galectin-1, galectin-3, and galectin-9), as well as hyaluronic acid-binding proteins. As glycoscience technologies advance, opportunities for enhanced understanding of glycans and their roles in leukocyte cell biology provide increasing opportunities for discovery and therapeutic intervention. PMID:27004978

Galectin-9 as a prognostic factor with antimetastatic potential in breast cancer.

PubMed

Irie, Akemi; Yamauchi, Akira; Kontani, Keiichi; Kihara, Minoru; Liu, Dage; Shirato, Yukako; Seki, Masako; Nishi, Nozomu; Nakamura, Takanori; Yokomise, Hiroyasu; Hirashima, Mitsuomi

2005-04-15

Galectin-9, a member of the beta-galactoside-binding galectin family, induces aggregation of certain cell types. We assessed the contribution of galectin-9 to the aggregation of breast cancer cells as well as the relation between galectin-9 expression in tumor tissue and distant metastasis in patients with breast cancer. Subclones of MCF-7 breast cancer cells with high or low levels of galectin-9 expression were established and either cultured on plastic dishes or transplanted into nude mice. The tumors of 84 patients with breast cancer were tested for galectin-9 expression by immunohistochemistry. The patients were followed up for 14 years. MCF-7 subclones with a high level of galectin-9 expression formed tight clusters during proliferation in vitro, whereas a subclone (K10) with the lowest level of galectin-9 expression did not. However, K10 cells stably transfected with a galectin-9 expression vector aggregated in culture and in nude mice. Ectopic expression of galectin-9 also reduced MCF-7 cell adhesion to extracellular matrix proteins. Tumors of 42 of the 84 patients were galectin-9 positive, and those of 19 of the 21 patients with distant metastasis were galectin-9 negative. None of the 13 patients with galectin-9-positive tumors and lymph node metastasis up to level II manifested distant metastasis. The cumulative disease-free survival ratio for galectin-9-positive patients was more favorable than that for the galectin-9-negative group (P < 0.0001). Multivariate analysis revealed that galectin-9 status influenced distant metastasis independently of and to a greater extent than lymph node metastasis. Galectin-9 is a possible prognostic factor with antimetastatic potential in breast cancer.

Galectin-3, osteopontin and successful aging.

PubMed

Sanchis-Gomar, Fabian; Santos-Lozano, Alejandro; Pareja-Galeano, Helios; Garatachea, Nuria; Alis, Rafael; Fiuza-Luces, Carmen; Morán, María; Emanuele, Enzo; Lucia, Alejandro

2016-05-01

Individuals who reach exceptional longevity (100+ years of age) free of common chronic age diseases (i.e. 'dodgers') arguably represent the paradigm of successful aging in humans. As such, identification of potential biomarkers associated with this phenomenon is of medical interest. We measured serum levels of galectin-3 and osteopontin, both of which have been shown to be linked with major chronic or aging-related disorders in younger populations, in centenarian 'dodgers' (n=81; 40 men; 100-104 years) and healthy controls (n=41; 24 men, 70-80 years). Both biomarkers showed significantly lower values (p<0.001) in the former (galectin-3: 2.4±1.7 vs. 4.8±2.8 ng/mL; osteopontin: 38.1±27.7 vs. 72.6±33.1 μg/mL). Logistic regression analysis identified the combination of these two biomarkers as a significant predictor variable associated with successful aging regardless of sex (p<0.001). The area under the curve (AUC) classified the ability of galectin-3 and osteopontin to predict the likelihood of successful aging as 'fair' (AUC=0.75) and 'good' (AUC=0.80), respectively. Particularly, the combination of the two biomarkers showed good discriminatory power for successful aging (AUC=0.86), with sensitivity=83% and specificity=74%. Lower levels of both galectin-3 and osteopontin are associated with successful aging, representing potential biomarkers of this condition. Our cross-sectional data must be however approached with caution. Further research is necessary to replicate the present preliminary results in other cohorts and to identify the potential use of galectin-3 and osteopontin as potential targets (or at least predictors) in future personalized anti-aging therapies.

Biomarkers of Myocardial Stress and Fibrosis as Predictors of Mode of Death in Patients with Chronic Heart Failure

PubMed Central

Ahmad, Tariq; Fiuzat, Mona; Neely, Ben; Neely, Megan; Pencina, Michael J.; Kraus, William E.; Zannad, Faiez; Whellan, David J.; Donahue, Mark; Piña, Ileana L.; Adams, Kirkwood; Kitzman, Dalane W.; O’Connor, Christopher M.; Felker, G. Michael

2014-01-01

Objective To determine whether biomarkers of myocardial stress and fibrosis improve prediction of mode of death in patients with chronic heart failure. Background The two most common modes of death in patients with chronic heart failure are pump failure and sudden cardiac death. Prediction of mode of death may facilitate treatment decisions. The relationship between NT-proBNP, galectin-3, and ST2, biomarkers that reflect different pathogenic pathways in heart failure (myocardial stress and fibrosis), and mode of death is unknown. Methods HF-ACTION was a randomized controlled trial of exercise training vs. usual care in patients with chronic heart failure due to left ventricular systolic dysfunction (LVEF<35%). An independent clinical events committee prospectively adjudicated mode of death. NT-proBNP, galectin-3, and ST2 levels were assessed at baseline in 813 subjects. Associations between biomarkers and mode of death were assessed using cause-specific Cox-proportional hazards modeling, and interaction testing was used to measure differential association between biomarkers and pump failure versus sudden cardiac death. Discrimination and risk reclassification metrics were used to assess the added value of galectin-3 and ST2 in predicting mode of death risk beyond a clinical model that included NT-proBNP. Results After a median follow up of 2.5 years, there were 155 deaths: 49 from pump failure 42 from sudden cardiac death, and 64 from other causes. Elevations in all biomarkers were associated with increased risk of both pump failure and sudden cardiac death in both adjusted and unadjusted analyses. In each case, increases in the biomarker had a stronger association with pump failure than sudden cardiac death but this relationship was attenuated after adjustment for clinical risk factors. Clinical variables along with NT-proBNP levels were stronger predictors of pump failure (C statistic: 0.87) than sudden cardiac death (C statistic: 0.73). Addition of ST2 and galectin-3 led to improved net risk classification of 11% for sudden cardiac death, but not pump failure. Conclusions Clinical predictors along with NT-proBNP levels were strong predictors of pump failure risk, with insignificant incremental contributions of ST2 and galectin-3. Predictability of sudden cardiac death risk was less robust and enhanced by information provided by novel biomarkers. PMID:24952693

Temporal Characterization of Microglia/Macrophage Phenotypes in a Mouse Model of Neonatal Hypoxic-Ischemic Brain Injury

PubMed Central

Hellström Erkenstam, Nina; Smith, Peter L. P.; Fleiss, Bobbi; Nair, Syam; Svedin, Pernilla; Wang, Wei; Boström, Martina; Gressens, Pierre; Hagberg, Henrik; Brown, Kelly L.; Sävman, Karin; Mallard, Carina

2016-01-01

Immune cells display a high degree of phenotypic plasticity, which may facilitate their participation in both the progression and resolution of injury-induced inflammation. The purpose of this study was to investigate the temporal expression of genes associated with classical and alternative polarization phenotypes described for macrophages and to identify related cell populations in the brain following neonatal hypoxia-ischemia (HI). HI was induced in 9-day old mice and brain tissue was collected up to 7 days post-insult to investigate expression of genes associated with macrophage activation. Using cell-markers, CD86 (classic activation) and CD206 (alternative activation), we assessed temporal changes of CD11b+ cell populations in the brain and studied the protein expression of the immunomodulatory factor galectin-3 in these cells. HI induced a rapid regulation (6 h) of genes associated with both classical and alternative polarization phenotypes in the injured hemisphere. FACS analysis showed a marked increase in the number of CD11b+CD86+ cells at 24 h after HI (+3667%), which was coupled with a relative suppression of CD11b+CD206+ cells and cells that did not express neither CD86 nor CD206. The CD11b+CD206+ population was mixed with some cells also expressing CD86. Confocal microscopy confirmed that a subset of cells expressed both CD86 and CD206, particularly in injured gray and white matter. Protein concentration of galectin-3 was markedly increased mainly in the cell population lacking CD86 or CD206 in the injured hemisphere. These cells were predominantly resident microglia as very few galectin-3 positive cells co-localized with infiltrating myeloid cells in Lys-EGFP-ki mice after HI. In summary, HI was characterized by an early mixed gene response, but with a large expansion of mainly the CD86 positive population during the first day. However, the injured hemisphere also contained a subset of cells expressing both CD86 and CD206 and a large population that expressed neither activation marker CD86 nor CD206. Interestingly, these cells expressed the highest levels of galectin-3 and were found to be predominantly resident microglia. Galectin-3 is a protein involved in chemotaxis and macrophage polarization suggesting a novel role in cell infiltration and immunomodulation for this cell population after neonatal injury. PMID:28018179

Galectin-3 in heart failure with preserved ejection fraction. A RELAX trial substudy (Phosphodiesterase-5 Inhibition to Improve Clinical Status and Exercise Capacity in Diastolic Heart Failure).

PubMed

AbouEzzeddine, Omar F; Haines, Phillip; Stevens, Susanna; Nativi-Nicolau, Jose; Felker, G Michael; Borlaug, Barry A; Chen, Horng H; Tracy, Russell P; Braunwald, Eugene; Redfield, Margaret M

2015-03-01

This study hypothesized that elevated galectin-3 (Gal-3) levels would identify patients with more advanced heart failure (HF) with preserved ejection fraction (HFpEF) as assessed by key pathophysiological domains. Gal-3 is implicated in the pathogenesis of cardiac fibrosis but is also increased with normal aging and renal dysfunction. Cardiac fibrosis may contribute to cardiac dysfunction, exercise intolerance, and congestion in HFpEF. Two hundred eight patients from the RELAX (Phosphodiesterase-5 Inhibition to Improve Clinical Status and Exercise Capacity in Diastolic Heart Failure) trial of sildenafil in HFpEF had Gal-3 measured at enrollment. Pathophysiological domains assessed included biomarkers of neurohumoral activation, fibrosis, inflammation and myocardial necrosis, congestion severity and quality of life, cardiac structure and function, and exercise performance. Analysis adjusted for age, sex, and/or cystatin-C levels. Potential interaction between baseline Gal-3 and treatment (sildenafil) effect on the RELAX study primary endpoint (change in peak oxygen consumption) was tested. Gal-3 levels were associated with age and severity of renal dysfunction. Adjusting for age, sex, and/or cystatin-C, Gal-3 was not associated with biomarkers of neurohumoral activation, fibrosis, inflammation or myocardial necrosis, congestion or quality-of-life impairment, cardiac remodeling or dysfunction, or exercise intolerance. Gal-3 did not identify patients who responded to phosphodiesterase type 5 (PDE-5) inhibitors (interaction p = 0.53). In overt HFpEF, Gal-3 was related to severity of renal dysfunction and accounting for this, was not independently associated with severity of pathophysiological derangements or response PDE-5 inhibition. These findings underscore the need to adjust for renal function when interpreting Gal-3 levels, and call into question the value of Gal-3 to quantify disease severity in overt HFpEF. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Elevated serum galectin-9 levels in patients with atopic dermatitis.

PubMed

Nakajima, Rina; Miyagaki, Tomomitsu; Oka, Tomonori; Nakao, Momoko; Kawaguchi, Makiko; Suga, Hiraku; Morimura, Sohshi; Kai, Hiromichi; Asano, Yoshihide; Tada, Yayoi; Kadono, Takafumi; Sato, Shinichi; Sugaya, Makoto

2015-07-01

Galectin-9 is a member of the galectin family that has a wide spectrum of biological functions. Among them, galectin-9 has been known mainly as a potent chemoattractant for eosinophils. In addition, galectin-9 alters the T-cell balance by negatively regulating T-helper (Th)1 and Th17 cells, resulting in Th2 polarization. Atopic dermatitis (AD) is a skin allergic disease characterized by peripheral eosinophilia, mast cell activation and predominance of Th2 cells. To investigate possible roles of galectin-9 in AD, we measured serum galectin-9 levels in AD patients and investigated galectin-9 expression in lesional skin by immunohistochemistry. Serum galectin-9 levels in patients with AD were significantly higher than those in healthy controls and correlated with the Eczema Area and Severity Index. Serum galectin-9 levels were decreased after treatment, accompanied by improvement of skin lesions. Immunohistochemical study revealed that galectin-9 was expressed on epidermal keratinocytes and mast cells in lesional skin of AD. Our results suggest that elevated galectin-9 expression is associated with progression of AD and that galectin-9 could be a therapeutic target in AD. © 2015 Japanese Dermatological Association.

Novel INTeraction of MUC4 and galectin: potential pathobiological implications for metastasis in lethal pancreatic cancer.

PubMed

Senapati, Shantibhusan; Chaturvedi, Pallavi; Chaney, William G; Chakraborty, Subhankar; Gnanapragassam, Vinayaga S; Sasson, Aaron R; Batra, Surinder K

2011-01-15

Several studies have reported aberrant expression of MUC4 in pancreatic cancer (PC), which is associated with tumorigenicity and metastasis. Mechanisms through which MUC4 promote metastasis of PC cells to distant organs are poorly defined. Identification of MUC4-galectin-3 interaction and its effect on the adhesion of cancer cells to endothelial cells were done by immunoprecipitation and cell-cell adhesion assays, respectively. Serum galectin-3 level for normal and PC patients were evaluated through ELISA. In the present study, we have provided clinical evidence that the level of galectin-3 is significantly elevated in the sera of PC patients with metastatic disease compared with patients without metastasis (P = 0.04) and healthy controls (P = 0.00001). Importantly, for the first time, we demonstrate that MUC4 present on the surface of circulating PC cells plays a significant role in the transient and reversible attachment (docking) of circulating tumor cells to the surface of endothelial cells. Further, exogenous galectin-3 at concentrations similar to that found in the sera of PC patients interacts with MUC4 via surface glycans such as T antigens, which results in the clustering of MUC4 on the cell surface and a stronger attachment (locking) of circulating tumor cells to the endothelium. Altogether, these findings suggest that PC cell-associated MUC4 helps in the docking of tumor cells on the endothelial surface. During cancer progression, MUC4-galectin-3 interaction-mediated clustering of MUC4 may expose the surface adhesion molecules, which in turn promotes a stronger attachment (locking) of tumor cells to the endothelial surface. ©2010 AACR.

IDO and galectin-3 hamper the ex vivo generation of clinical grade tumor-specific T cells for adoptive cell therapy in metastatic melanoma.

PubMed

Melief, Sara M; Visser, Marten; van der Burg, Sjoerd H; Verdegaal, Els M E

2017-07-01

Adoptive T cell transfer (ACT) with ex vivo-expanded tumor-reactive T cells proved to be successful for the treatment of metastatic melanoma patients. Mixed lymphocyte tumor cell cultures (MLTC) can be used to generate tumor-specific T cells for ACT; however, in a number of cases tumor-reactive T cell, expansion is far from optimal. We hypothesized that this is due to tumor intrinsic and extrinsic factors and aimed to identify and manipulate these factors so to optimize our clinical, GMP-compliant MLTC protocol. We found that the tumor cell produced IDO and/or galectin-3, and the accumulation of CD4 + CD25 hi FoxP3 + T cells suppressed the expansion of tumor-specific T cells in the MLTC. Strategies to eliminate CD4 + CD25 hi FoxP3 + T cells during culture required the depletion of the whole CD4 + T cell population and were found to be undesirable. Blocking of IDO and galectin-3 was feasible and resulted in improved efficiency of the MLTC. Implementation of these findings in clinical protocols for ex vivo expansion of tumor-reactive T cells holds promise for an increased therapeutic potential of adoptive cell transfer treatments with tumor-specific T cells.

Studies on the role of goat heart galectin-1 as an erythrocyte membrane perturbing agent.

PubMed

Ashraf, Ghulam Md; Perveen, Asma; Zaidi, Syed Kashif; Tabrez, Shams; Kamal, Mohammad A; Banu, Naheed

2015-01-01

Galectins are β-galactoside binding lectins with a potential hemolytic role on erythrocyte membrane integrity and permeability. In the present study, goat heart galectin-1 (GHG-1) was purified and investigated for its hemolytic actions on erythrocyte membrane. When exposed to various saccharides, lactose and sucrose provided maximum protection against hemolysis, while glucose and galactose provided lesser protection against hemolysis. GHG-1 agglutinated erythrocytes were found to be significantly hemolyzed in comparison with unagglutinated erythrocytes. A concentration dependent rise in the hemolysis of trypsinized rabbit erythrocytes was observed in the presence of GHG-1. Similarly, a temperature dependent gradual increase in percent hemolysis was observed in GHG-1 agglutinated erythrocytes as compared to negligible hemolysis in unagglutinated cells. The hemolysis of GHG-1 treated erythrocytes showed a sharp rise with the increasing pH up to 7.5 which became constant till pH 9.5. The extent of erythrocyte hemolysis increased with the increase in the incubation period, with maximum hemolysis after 5 h of incubation. The results of this study establish the ability of galectins as a potential hemolytic agent of erythrocyte membrane, which in turn opens an interesting avenue in the field of proteomics and glycobiology.

Expression of immune checkpoint molecules in endometrial carcinoma

PubMed Central

LIU, JIA; LIU, YULING; WANG, WULIANG; WANG, CHENYANG; CHE, YANHONG

2015-01-01

The main obstacle in the development of an effective tumor vaccine is the inherent ability of tumors to evade immune responses. Tumors often use common immune mechanisms and regulators to evade the immune system. The present study aimed to analyze the expression levels of indoleamine 2,3-dioxygenase (IDO), programmed death-ligand (PD-L) 1, PD-L2, B7-H4, galectin-1 and galectin-3 in tissue samples from patients with endometrial carcinoma, in order to detect the immunosuppressive environment of endometrial carcinomas. The levels of IDO, PD-L1, PD-L2 and B7-H4 were analyzed by immunohistochemical methods, and the levels of galectin-1 and galectin-3 in tumor lysates were determined using ELISA. PD-L2 was expressed at low levels in the majority of tumor samples. IDO expression was detected in 38, 63 and 43% of primary endometrial carcinoma, recurrent endometrial carcinoma, and metastatic endometrial carcinoma specimens, respectively. Positive expression rates for PD-L1 were 83% in primary endometrial carcinoma, 68% in recurrent endometrial carcinoma, and 100% in metastatic endometrial carcinoma, whereas B7-H4 expression was detected in 100% of both primary endometrial carcinoma and recurrent endometrial carcinoma samples, and in 96% of metastatic endometrial carcinoma specimens. The expression levels of galectin-1 and galectin-3 were not significantly different between the normal and tumor specimens. The results of the present study suggest that the interaction between PD-1/PD-L1 and B7-H4 may be a potential target for immune intervention in the treatment of endometrial carcinoma. Furthermore, the results may provide the basis for immunosuppressant therapy in the treatment of patients with uterine cancer. PMID:26640578

Association Between Plasma Level of Galectin-9 and Survival of Patients With Drug-Induced Acute Liver Failure.

PubMed

Rosen, Hugo R; Biggins, Scott W; Niki, Toshiro; Gralla, Jane; Hillman, Holly; Hirashima, Mitsuomi; Schilsky, Michael; Lee, William M

2016-04-01

Fewer than 50% of patients with acute liver failure (ALF) recover spontaneously, and ALF has high mortality without liver transplantation. Kupffer cells have been reported to mediate liver inflammation during drug-induced injury. Galectin-9 is produced by Kupffer cells and has diverse roles in regulating immunity. We investigated whether plasma levels of galectin-9 are associated with outcomes of patients with ALF. We analyzed plasma samples (collected at time of hospital admission) and clinical data from 149 patients included in the Acute Liver Failure Study Group from July 2006 through November 2010 (110 had acetaminophen-induced hepatotoxicity and 39 had nonacetaminophen drug-induced liver injury). We compared data with those from all patients enrolled in the study (from July 1, 2006 through October 30, 2013), and from healthy individuals of similar ages with no evidence of liver disease (control subjects). Plasma levels of galectin-9 were measured using a polyclonal antibody and colorimetric assay. Patients with ALF had statistically higher plasma levels of galectin-9 than control subjects, but levels did not differ significantly between patients with acetaminophen-induced liver injury and drug-induced liver injury. A level of galectin-9 above 690 pg/mL was associated with a statistically significant increase in risk for mortality or liver transplantation caused by ALF. Competing risk analyses associated level of galectin-9 with transplant-free survival, independently of Model For End-Stage Liver Disease score or systemic inflammatory response syndrome. A one-time measurement of plasma galectin-9 level can be used to assign patients with ALF to high-, intermediate-, and low-risk groups. The combination of galectin-9 level and Model For End-Stage Liver Disease score was more closely associated with patient outcome than either value alone. These data might be used to determine patient prognoses and prioritize patients for liver transplantation. ClinicalTrials.gov ID NCT00518440. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

Advanced glycation endproducts link inflammatory cues to upregulation of galectin-1 in diabetic retinopathy.

PubMed

Kanda, Atsuhiro; Dong, Yoko; Noda, Kousuke; Saito, Wataru; Ishida, Susumu

2017-11-23

Diabetic retinopathy (DR) is an inflammatory and progressive vaso-occlusive disease resulting in angiogenesis. Galectin-1 is a hypoxia-induced angiogenic factor associated with cancer and proliferative DR. Here we reveal a significant upregulation of galectin-1 in eyes of DR patients along with progression of clinical stages beginning from the pre-ischemic, inflammatory stage with diabetic macular edema, but not in eyes with non-diabetic retinal vascular occlusions. As for its regulatory mechanism unrelated to hypoxia but selective to DR, in vitro galectin-1/LGALS1 expression was shown to increase after application to Müller glial cells with interleukin (IL)-1β, which was induced in monocyte-derived macrophages and microglial cells via toll-like receptor (TLR) 4 signaling stimulated by advanced glycation endproducts (AGE). In vivo inhibition of AGE generation with aminoguanidine, macrophage depletion with clodronate liposomes, and antibody-based blockade of Il-1β and Tlr4 attenuated diabetes-induced retinal Lgals1 expression in mice. Fibrovascular tissues from proliferative DR eyes were immunoreactive for AGE, TRL4 and IL-1β in macrophages, and IL-1β receptor-positive glial cells expressed galectin-1. Therefore, diabetes-induced retinal AGE accumulation was suggested to activate IL-1β-related inflammatory cues in macrophages followed by Müller cells, linking to galectin-1 upregulation in human DR with time. Our data highlight AGE-triggered inflammation as the DR-selective inducer of galectin-1.

Viewing a humorous film decreases IgE production by seminal B cells from patients with atopic eczema.

PubMed

Kimata, Hajime

2009-02-01

Sperms induced IgE production by seminal B cells from patients with atopic eczema via interaction of B cells with galectin-3 on sperms. We studied the effect of viewing a humorous film on IgE production by seminal B cells cultured with sperms. Twenty-four male patients with atopic eczema viewed a humorous film (Modern Times, featuring Charlie Chaplin). Just before and immediately after viewing, semen was collected, and seminal B cells and sperms were purified. Seminal B cells were cultured with sperms and IgE production was measured, while expression of galectin-3 on sperms was assessed. After viewing the humorous film, IgE production by B cells cultured with sperms was significantly decreased. Moreover, expression of galectin-3 on sperms was reduced. Viewing a humorous film reduced galectin-3 expression on sperms, which in turn decreased IgE production by seminal B cells cultured with sperms. These results indicate that viewing a humorous film may be helpful for the study and treatment of local IgE production and allergy in the reproductive tract.

A potential pathophysiological role for galectins and the renin-angiotensin system in preeclampsia.

PubMed

Blois, Sandra M; Dechend, Ralf; Barrientos, Gabriela; Staff, Anne Cathrine

2015-01-01

This review discusses a potential role of galectins and the renin-angiotensin system (RAS) in the pathophysiology of preeclampsia (PE). Preeclampsia affects between 3 and 5 % of all pregnancies and is a heterogeneous disease, which may be caused by multiple factors. The only cure is the delivery of the placenta, which may result in a premature delivery and baby. Probably due to its heterogeneity, PE studies in human have hitherto only led to the identification of a limited number of factors involved in the pathogenesis of the disease. Animal models, particularly in mice and rats, have been used to gain further insight into the molecular pathology behind PE. In this review, we discuss the picture emerging from human and animal studies pointing to galectins and the RAS being associated with the PE syndrome and affecting a broad range of cellular signaling components. Moreover, we review the epidemiological evidence for PE increasing the risk of future cardiovascular disease later in life.

Galectin-3: One Molecule for an Alphabet of Diseases, from A to Z

PubMed Central

Sciacchitano, Salvatore; Lavra, Luca; Morgante, Alessandra; Ulivieri, Alessandra; Magi, Fiorenza; De Francesco, Gian Paolo; Bellotti, Carlo; Salehi, Leila B.; Ricci, Alberto

2018-01-01

Galectin-3 (Gal-3) regulates basic cellular functions such as cell–cell and cell–matrix interactions, growth, proliferation, differentiation, and inflammation. It is not surprising, therefore, that this protein is involved in the pathogenesis of many relevant human diseases, including cancer, fibrosis, chronic inflammation and scarring affecting many different tissues. The papers published in the literature have progressively increased in number during the last decades, testifying the great interest given to this protein by numerous researchers involved in many different clinical contexts. Considering the crucial role exerted by Gal-3 in many different clinical conditions, Gal-3 is emerging as a new diagnostic, prognostic biomarker and as a new promising therapeutic target. The current review aims to extensively examine the studies published so far on the role of Gal-3 in all the clinical conditions and diseases, listed in alphabetical order, where it was analyzed. PMID:29373564

Biomarkers of myocardial stress and fibrosis as predictors of mode of death in patients with chronic heart failure.

PubMed

Ahmad, Tariq; Fiuzat, Mona; Neely, Benjamin; Neely, Megan L; Pencina, Michael J; Kraus, William E; Zannad, Faiez; Whellan, David J; Donahue, Mark P; Piña, Ileana L; Adams, Kirkwood F; Kitzman, Dalane W; O'Connor, Christopher M; Felker, G Michael

2014-06-01

The aim of this study was to determine whether biomarkers of myocardial stress and fibrosis improve prediction of the mode of death in patients with chronic heart failure. The 2 most common modes of death in patients with chronic heart failure are pump failure and sudden cardiac death. Prediction of the mode of death may facilitate treatment decisions. The relationship between amino-terminal pro-brain natriuretic peptide (NT-proBNP), galectin-3, and ST2, biomarkers that reflect different pathogenic pathways in heart failure (myocardial stress and fibrosis), and mode of death is unknown. HF-ACTION (Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training) was a randomized controlled trial of exercise training versus usual care in patients with chronic heart failure due to left ventricular systolic dysfunction (left ventricular ejection fraction ≤35%). An independent clinical events committee prospectively adjudicated mode of death. NT-proBNP, galectin-3, and ST2 levels were assessed at baseline in 813 subjects. Associations between biomarkers and mode of death were assessed using cause-specific Cox proportional hazards modeling, and interaction testing was used to measure differential associations between biomarkers and pump failure versus sudden cardiac death. Discrimination and risk reclassification metrics were used to assess the added value of galectin-3 and ST2 in predicting mode of death risk beyond a clinical model that included NT-proBNP. After a median follow-up period of 2.5 years, there were 155 deaths: 49 from pump failure, 42 from sudden cardiac death, and 64 from other causes. Elevations in all biomarkers were associated with increased risk for both pump failure and sudden cardiac death in both adjusted and unadjusted analyses. In each case, increases in the biomarker had a stronger association with pump failure than sudden cardiac death, but this relationship was attenuated after adjustment for clinical risk factors. Clinical variables along with NT-proBNP levels were stronger predictors of pump failure (C statistic: 0.87) than sudden cardiac death (C statistic: 0.73). Addition of ST2 and galectin-3 led to improved net risk classification of 11% for sudden cardiac death, but not pump failure. Clinical predictors along with NT-proBNP levels were strong predictors of pump failure risk, with insignificant incremental contributions of ST2 and galectin-3. Predictability of sudden cardiac death risk was less robust and enhanced by information provided by novel biomarkers. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Studies on the role of goat heart galectin-1 as an erythrocyte membrane perturbing agent

PubMed Central

Ashraf, Ghulam Md; Perveen, Asma; Zaidi, Syed Kashif; Tabrez, Shams; Kamal, Mohammad A.; Banu, Naheed

2014-01-01

Galectins are β-galactoside binding lectins with a potential hemolytic role on erythrocyte membrane integrity and permeability. In the present study, goat heart galectin-1 (GHG-1) was purified and investigated for its hemolytic actions on erythrocyte membrane. When exposed to various saccharides, lactose and sucrose provided maximum protection against hemolysis, while glucose and galactose provided lesser protection against hemolysis. GHG-1 agglutinated erythrocytes were found to be significantly hemolyzed in comparison with unagglutinated erythrocytes. A concentration dependent rise in the hemolysis of trypsinized rabbit erythrocytes was observed in the presence of GHG-1. Similarly, a temperature dependent gradual increase in percent hemolysis was observed in GHG-1 agglutinated erythrocytes as compared to negligible hemolysis in unagglutinated cells. The hemolysis of GHG-1 treated erythrocytes showed a sharp rise with the increasing pH up to 7.5 which became constant till pH 9.5. The extent of erythrocyte hemolysis increased with the increase in the incubation period, with maximum hemolysis after 5 h of incubation. The results of this study establish the ability of galectins as a potential hemolytic agent of erythrocyte membrane, which in turn opens an interesting avenue in the field of proteomics and glycobiology. PMID:25561893

Full-length model of the human galectin-4 and insights into dynamics of inter-domain communication

NASA Astrophysics Data System (ADS)

Rustiguel, Joane K.; Soares, Ricardo O. S.; Meisburger, Steve P.; Davis, Katherine M.; Malzbender, Kristina L.; Ando, Nozomi; Dias-Baruffi, Marcelo; Nonato, Maria Cristina

2016-09-01

Galectins are proteins involved in diverse cellular contexts due to their capacity to decipher and respond to the information encoded by β-galactoside sugars. In particular, human galectin-4, normally expressed in the healthy gastrointestinal tract, displays differential expression in cancerous tissues and is considered a potential drug target for liver and lung cancer. Galectin-4 is a tandem-repeat galectin characterized by two carbohydrate recognition domains connected by a linker-peptide. Despite their relevance to cell function and pathogenesis, structural characterization of full-length tandem-repeat galectins has remained elusive. Here, we investigate galectin-4 using X-ray crystallography, small- and wide-angle X-ray scattering, molecular modelling, molecular dynamics simulations, and differential scanning fluorimetry assays and describe for the first time a structural model for human galectin-4. Our results provide insight into the structural role of the linker-peptide and shed light on the dynamic characteristics of the mechanism of carbohydrate recognition among tandem-repeat galectins.

Regulatory Eosinophils Suppress T Cells Partly through Galectin-10.

PubMed

Lingblom, Christine; Andersson, Jennie; Andersson, Kerstin; Wennerås, Christine

2017-06-15

Eosinophils have the capacity to regulate the function of T cell subsets. Our aim was to test the hypothesis of the existence of a regulatory subset of eosinophils. Human eosinophils were incubated with T cells that were stimulated with allogeneic leukocytes or CD3/CD28 cross-linking. After 2 d of coculture, 11% of the eosinophils gained CD16 expression. A CD16 hi subset of eosinophils, encompassing 1-5% of all eosinophils, was also identified in the blood of healthy subjects. FACS sorting showed that these CD16 hi eosinophils were significantly stronger suppressors of T cell proliferation than were conventional CD16 neg eosinophils. Human eosinophils contain stores of the immunoregulatory protein galectin-10. We found that Ab-mediated neutralization of galectin-10 partially abrogated the suppressive function of the eosinophils. Moreover, recombinant galectin-10 by itself was able to suppress T cell proliferation. Finally, we detected galectin-10-containing immune synapses between eosinophils and lymphocytes. To conclude, we describe a subset of suppressive eosinophils expressing CD16 that may escape detection because CD16-based negative selection is the standard procedure for the isolation of human eosinophils. Moreover, we show that galectin-10 functions as a T cell-suppressive molecule in eosinophils. Copyright © 2017 by The American Association of Immunologists, Inc.

Factors Associated With Inadequate Effectiveness of a Multidisciplinary Disease Management Program in Heart Failure Patients Stratified by Galectin 3 Level.

PubMed

Liu, Min-Hui; Wang, Chao-Hung; Chiou, Ai-Fu; Yang, Ning-I; Kuo, Li-Tang

2016-07-21

This study investigated whether multidisciplinary disease management programs (MDPs) exert the same effects in heart failure (HF) patients across risk levels stratified by galectin-3 (Gal-3) level and what factors are associated with inadequate effectiveness of MDP. We used a longitudinal follow-up design based on a previous randomized trial. A total of 355 stabilized hospitalized HF patients were enrolled. The effects of MDP on death and HF-related rehospitalization were analyzed according to Gal-3 levels. During the 4-year follow-up, Gal-3 levels predicted mortality and composite events (p < .001). Multivariable analysis demonstrated the event-lowering effect of MDP (hazard ratio [HR] = 0.49, p = .001 for death and HR = 0.50, p < .001 for composite events). However, the effect of MDP was inadequate for those with high Gal-3 levels (≥17.9 ng/ml), whose 4-year composite event rate was 43% in the MDP arm. Further analysis showed that, in patients with Gal-3 ≥ 17.9 ng/ml, the independent factors associated with a high composite event rate were no MDP, older age, worse New York Heart Association functional class, no angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker use, higher predischarge natriuretic peptide levels, and wider QRS complexes. The effectiveness of MDP for HF patients at high risk was inadequate. Our findings identified the characteristics of these MDP nonresponders. Better integration of advanced care plans based on strategies guided by Gal-3 level is needed to improve care quality. © The Author(s) 2016.

Galectins as Cancer Biomarkers

PubMed Central

Balan, Vitaly; Nangia-Makker, Pratima; Raz, Avraham

2010-01-01

Galectins are a group of proteins that bind β-galactosides through evolutionarily conserved sequence elements of the carbohydrate recognition domain (CRD). Proteins similar to galectins can be found in very primitive animals such as sponges. Each galectin has an individual carbohydrate binding preference and can be found in cytoplasm as well as in the nucleus. They also can be secreted through non-classical pathways and function extra-cellularly. Experimental and clinical data demonstrate a correlation between galectin expression and tumor progression and metastasis, and therefore, galectins have the potential to serve as reliable tumor markers. In this review, we describe the expression and role of galectins in different cancers and their clinical applications for diagnostic use. PMID:23658855

Potent pro-inflammatory and pro-fibrotic molecules, osteopontin and galectin-3, are not major disease modulators of laminin α2 chain-deficient muscular dystrophy

PubMed Central

Gawlik, Kinga I.; Holmberg, Johan; Svensson, Martina; Einerborg, Mikaela; Oliveira, Bernardo M. S.; Deierborg, Tomas; Durbeej, Madeleine

2017-01-01

A large number of human diseases are caused by chronic tissue injury with fibrosis potentially leading to organ failure. There is a need for more effective anti-fibrotic therapies. Congenital muscular dystrophy type 1A (MDC1A) is a devastating form of muscular dystrophy caused by laminin α2 chain-deficiency. It is characterized with early inflammation and build-up of fibrotic lesions, both in patients and MDC1A mouse models (e.g. dy3K/dy3K). Despite the enormous impact of inflammation on tissue remodelling in disease, the inflammatory response in MDC1A has been poorly described. Consequently, a comprehensive understanding of secondary mechanisms (impaired regeneration, enhanced fibrosis) leading to deterioration of muscle phenotype in MDC1A is missing. We have monitored inflammatory processes in dy3K/dy3K muscle and created mice deficient in laminin α2 chain and osteopontin or galectin-3, two pro-inflammatory and pro-fibrotic molecules drastically increased in dystrophic muscle. Surprisingly, deletion of osteopontin worsened the phenotype of dy3K/dy3K mice and loss of galectin-3 did not reduce muscle pathology. Our results indicate that osteopontin could even be a beneficial immunomodulator in MDC1A. This knowledge is essential for the design of future therapeutic interventions for muscular dystrophies that aim at targeting inflammation, especially that osteopontin inhibition has been suggested for Duchenne muscular dystrophy therapy. PMID:28281577

Different expression patterns of LGALS1 and LGALS3 in polycythemia vera, essential thrombocythemia and primary myelofibrosis.

PubMed

Moura, L G; Tognon, R; Nunes, N S; Rodrigues, L Cataldi; Ferreira, A F; Kashima, S; Covas, D T; Santana, M; Souto, E X; Perobelli, L; Simões, B P; Dias-Baruffi, M; Castro, F A

2016-10-01

Despite all the knowledge, the cellular and molecular mechanisms involved in myeloproliferative neoplasm (MPN) pathophysiology remain unclear. Authors have shown galectin-1 (Gal-1) and 3 playing roles in tumour angiogenesis and fibrosis, which were correlated with poor prognosis in patients with MPN. In the present study LGALS1 and LGALS3 were differently expressed between polycythemia vera, essential thrombocythemia (ET) and primary myelofibrosis (PMF) diseases. Increased LGALS3 expression was associated with a negative JAK2 V617F status mutation in leucocytes from PMF but not in patients with ET without this mutation. However, a positive Janus kinase 2 (JAK2) V617F cell line established from patients with ET (SET-2 cells) when treated with JAK inhibitor presented high levels of LGALS3. Additionally, high LGALS1 expression was found in CD34(+) cells but not in leucocytes from patients with PMF, in absence of JAK2 V617F mutation, and also in SET-2 cells treated with JAK inhibitor. Thus, our findings indicate that differential expression of LGALS1 and/or LGALS3 in patients with MPN is linked with JAK2 V617F status mutation in these diseases and state of cell differentiation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Military Vision Research Program

DTIC Science & Technology

2011-02-01

present in vitreous appears to associate with the extracellular domain of PDGFRα • Galectin 3 was identified by mass spec as one of the vitreal...proteins that bound to the extracellular domain of PDGFRα • Recombinant galectin 3 did not prevent PDGF from activating PDGFRα, and is therefore not...February 28, 2011 2. REPORT TYPE Final 3 . DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-09-2-0091

Ligand-mediated Galectin-1 endocytosis prevents intraneural H2O2 production promoting F-actin dynamics reactivation and axonal re-growth.

PubMed

Quintá, Héctor R; Wilson, Carlos; Blidner, Ada G; González-Billault, Christian; Pasquini, Laura A; Rabinovich, Gabriel A; Pasquini, Juana M

2016-09-01

Axonal growth cone collapse following spinal cord injury (SCI) is promoted by semaphorin3A (Sema3A) signaling via PlexinA4 surface receptor. This interaction triggers intracellular signaling events leading to increased hydrogen peroxide levels which in turn promote filamentous actin (F-actin) destabilization and subsequent inhibition of axonal re-growth. In the current study, we demonstrated that treatment with galectin-1 (Gal-1), in its dimeric form, promotes a decrease in hydrogen peroxide (H2O2) levels and F-actin repolimerization in the growth cone and in the filopodium of neuron surfaces. This effect was dependent on the carbohydrate recognition activity of Gal-1, as it was prevented using a Gal-1 mutant lacking carbohydrate-binding activity. Furthermore, Gal-1 promoted its own active ligand-mediated endocytosis together with the PlexinA4 receptor, through mechanisms involving complex branched N-glycans. In summary, our results suggest that Gal-1, mainly in its dimeric form, promotes re-activation of actin cytoskeleton dynamics via internalization of the PlexinA4/Gal-1 complex. This mechanism could explain, at least in part, critical events in axonal regeneration including the full axonal re-growth process, de novo formation of synapse clustering, axonal re-myelination and functional recovery of coordinated locomotor activities in an in vivo acute and chronic SCI model. Axonal regeneration is a response of injured nerve cells critical for nerve repair in human spinal cord injury. Understanding the molecular mechanisms controlling nerve repair by Galectin-1, may be critical for therapeutic intervention. Our results show that Galectin-1; in its dimeric form, interferes with hydrogen peroxide production triggered by Semaphorin3A. The high levels of this reactive oxygen species (ROS) seem to be the main factor preventing axonal regeneration due to promotion of actin depolymerization at the axonal growth cone. Thus, Galectin-1 administration emerges as a novel therapeutic modality for promoting nerve repair and preventing axonal loss. Copyright © 2016 Elsevier Inc. All rights reserved.

Ocimum gratissimum retards breast cancer growth and progression and is a natural inhibitor of matrix metalloproteases

PubMed Central

Nangia-Makker, Pratima; Raz, Tirza; Tait, Larry; Shekhar, Malathy P.V.; Li, Hong; Balan, Vitaly; Makker, Hemanckur; Fridman, Rafael; Maddipati, Krishnarao; Raz, Avraham

2013-01-01

Ocimum genus (a.k.a holy basil or tulsi) is a dietary herb used for its multiple beneficial pharmacologic properties including anti-cancer activity. Here we show that crude extract of Ocimum gratissimum (OG) and its hydrophobic and hydrophilic fractions (HB and HL) differentially inhibit breast cancer cell chemotaxis and chemoinvasion in vitro and retard tumor growth and temporal progression of MCF10ADCIS.com xenografts, a model of human breast comedo-ductal carcinoma in situ (comedo-DCIS). OG-induced inhibition of tumor growth was associated with decreases in basement membrane disintegration, angiogenesis and MMP-2 and MMP-9 activities as confirmed by in situ gelatin zymography and cleavage of galectin-3. There was also decrease in MMP-2 and MMP-9 activities in the conditioned media of OG-treated MCF10AT1 and MCF10AT1-EIII8 premalignant human breast cancer cells as compared with control. The MMP-2 and MMP-9 inhibitory activities of OG were verified in vitro using gelatin, a synthetic fluorogenic peptide and recombinant galectin-3 as MMP substrates. Mice fed on OG-supplemented drinking water showed no adverse effects compared with control. These data suggest that OG is non-toxic and that the anti-cancer therapeutic activity of OG may in part be contributed by its MMP inhibitory activity. PMID:23380593

Contribution of immunocytochemical stainings for galectin-3, CD44, and HBME1 to fine-needle aspiration cytology diagnosis of papillary thyroid carcinoma.

PubMed

Das, Dilip K; Al-Waheeb, Salah K M; George, Sara S; Haji, Bahiyah I; Mallik, Mrinmay K

2014-06-01

In cytology practice some papillary thyroid carcinoma (PTC) cases have indeterminate diagnoses and overlapping cytological features with benign lesions. This study was undertaken to find out if immunocytochemistry using Galectin-3, CD-44 and HBME-1 could be of help in such situations. Forty-six cases consisting of 22 malignancy (PTC) cases, 7 suspicious of (S/O) PTC, 1 follicular neoplasm, 5 follicular lesion of undetermined significance (FLUS), and 11 benign (colloid goiter) cases diagnosed by FNA were included in this study. Staining reactions were graded in a sliding scale of -, 1+, 2+, 3+, and 4+. In an assessment of 100 cells, each cell with weak, and moderate to strong positive reaction were assigned a score of 1 and 4, respectively. Staining reaction of ≥+2 and scores >100 were considered positive. Frequency of cases with ≥+2 reaction, and scores >100 for each of Galectin-3, CD-44, and HBME-1 were significantly higher in PTC or combined PTC and S/O PTC cases as compared with FLUS and benign cases taken together (P = 0.01744 to 0.00000). When the cases were compared according to histological malignant and benign diagnoses, the difference was also significant in respect of ≥+2 reaction, and scores >100 for Galectin-3 and CD44 (P = 0.04923 to 0.00947); however, there was no significant difference, when these parameters for HBME1 were compared. Galectin 3, CD 44, and to some extent HBME 1 are useful immunocytochemical parameters with potential to support FNAC diagnosis of PTC, especially in situations with difficult differential diagnoses. Copyright © 2013 Wiley Periodicals, Inc.

Binding of galectin-1 to breast cancer cells MCF7 induces apoptosis and inhibition of proliferation in vitro in a 2D- and 3D- cell culture model.

PubMed

Geiger, Pamina; Mayer, Barbara; Wiest, Irmi; Schulze, Sandra; Jeschke, Udo; Weissenbacher, Tobias

2016-11-08

Galectin-1 (gal-1) belongs to the family of β-galactoside-binding proteins which primarily recognizes the Galβ1-4GlcNAc sequences of oligosaccharides associated with several cell surface glycoconjugates. The lectin recognizes correspondent glycoepitopes on human breast cancer cells. Galectin-1 is expressed both in normal and malignant tissues. Lymphatic organs naturally possessing high rates of apoptotic cells, express high levels of Galectin-1. Furthermore galectin-1 can initiate T cell apoptosis. Binding of galectin-1 to trophoblast tumor cells presenting the oncofetal Thomsen-Friedenreich (TF) carbohydrate antigen inhibits tumor cell proliferation. In this study we examined the impact galectin-1 has in vitro on cell proliferation, apoptotic potential and metabolic activity of MCF-7 and T-47D breast cancer cells in dependence to their expression of the Thomsen-Friedenreich (TF) tumor antigen. For proliferation and apoptosis assays cells were grown in presence of 10, 30 and 60 μg gal-1/ml medium. Cell proliferation was determined by a BrdU uptake ELISA. Detection of apoptotic cells was done by M30 cyto death staining, in situ nick translation and by a nucleosome ELISA method. Furthermore we studied the impact galectin-1 has on the metabolic activity of MCF-7 and T-47D cells in a homotypic three-dimensional spheroid cell culture model mimicking a micro tumour environment. Gal-1 inhibited proliferation of MCF-7 cells (strong expression of the TF epitope) but did not significantly change proliferation of T-47D cells (weak expression of the TF epitope). The incubation of MCF-7 cells with gal-1 raised number of apoptotic cells significantly. Treating the spheroids with 30 μg/ml galectin-1 in addition to standard chemotherapeutic regimes (FEC, TAC) resulted in further suppression of the metabolic activity in MCF-7 cells whereas T-47D cells were not affected. Our results demonstrate that galectin-1 can inhibit proliferation und metabolic cell activity and induce apoptosis in breast tumor cell lines with high expression levels of the Thomsen-Friedenreich (TF) antigen in monolayer and spheroid cell culture models.

Cell- and stage-specific localization of galectin-3, a β-galactoside-binding lectin, in a mouse model of experimental autoimmune encephalomyelitis.

PubMed

Itabashi, Tetsuya; Arima, Yasunobu; Kamimura, Daisuke; Higuchi, Kotaro; Bando, Yoshio; Takahashi-Iwanaga, Hiromi; Murakami, Masaaki; Watanabe, Masahiko; Iwanaga, Toshihiko; Nio-Kobayashi, Junko

2018-06-16

Multiple sclerosis (MS) is an autoimmune disease in which pathogenic T cells play an important role, and an experimental autoimmune encephalomyelitis (EAE) is used as an animal model of MS. Galectins are β-galactoside-binding lectins and involved in various physiological and pathological events. Among fifteen members of galectins, galectin-1, -8, and -9 play immunosuppressive roles in MS and EAE; however, the role of galectin-3 (gal-3) is complex and controversial. We examined expression of gal-3 in the spinal cord and nerve roots of EAE mice. No immunohistochemical signals were detected in naïve mice, whereas gal-3 appeared at lower lumbar levels of the spinal cord and nerve roots in EAE mice. In the spinal cord, gal-3-positive cells were activated microglia and/or infiltrating macrophages, which were round in shape and intensified for the lysosomal enzyme, cathepsin D, indicating elevated phagocytic activity. Gal-3-positive cells in the spinal cord were most abundant during the peak symptomatic period. In the recovery period, they disappeared from the spinal parenchyma but remained at moderate levels in the pia mater. Interestingly, gal-3-positive cells selectively appeared in ventral, but not dorsal, nerve roots running through the spinal canal, with expression peaking during the recovery period. In ventral nerve roots, the major cell type expressing gal-3 was a specific population of Schwann cells that surround unmyelinated axons and express the biosynthetic enzyme for l-serine, a potent neurotrophic amino acid. Gal-3 was also induced in Iba1/F4/80-positive macrophages, which engulf damaged myelin and axon debris. Thus, gal-3 is induced in distinct cell types that are engaged in removal of damaged axons and cell debris and axon regeneration and remyelination, suggesting a potential neuroprotective role of gal-3 in EAE mice. Copyright © 2018. Published by Elsevier Ltd.

Beneficial Effects of Galectin-3 Blockade in Vascular and Aortic Valve Alterations in an Experimental Pressure Overload Model

PubMed Central

Ibarrola, Jaime; Martínez-Martínez, Ernesto; Sádaba, J. Rafael; Arrieta, Vanessa; García-Peña, Amaia; Álvarez, Virginia; Fernández-Celis, Amaya; Gainza, Alicia; Rossignol, Patrick; Cachofeiro Ramos, Victoria; López-Andrés, Natalia

2017-01-01

Galectin-3 (Gal-3) is involved in cardiovascular fibrosis and aortic valve (AV) calcification. We hypothesized that Gal-3 pharmacological inhibition with modified citrus pectin (MCP) could reduce aortic and AV remodeling in normotensive rats with pressure overload (PO). Six weeks after aortic constriction, vascular Gal-3 expression was up-regulated in male Wistar rats. Gal-3 overexpression was accompanied by an increase in the aortic media layer thickness, enhanced total collagen, and augmented expression of fibrotic mediators. Further, vascular inflammatory markers as well as inflammatory cells content were greater in aorta from PO rats. MCP treatment (100 mg/kg/day) prevented the increase in Gal-3, media thickness, fibrosis, and inflammation in the aorta of PO rats. Gal-3 levels were higher in AVs from PO rats. This paralleled enhanced AV fibrosis, inflammation, as well as greater expression of calcification markers. MCP treatment prevented the increase in Gal-3 as well as fibrosis, inflammation, and calcification in AVs. Overall, Gal-3 is overexpressed in aorta and AVs from PO rats. Gal-3 pharmacological inhibition blocks aortic and AV remodeling in experimental PO. Gal-3 could be a new therapeutic approach to delay the progression and the development of aortic remodeling and AV calcification in PO. PMID:28758988

Galectin-1 as a potent target for cancer therapy: role in the tumor microenvironment.

PubMed

Ito, Koichi; Stannard, Kimberley; Gabutero, Elwyn; Clark, Amanda M; Neo, Shi-Yong; Onturk, Selda; Blanchard, Helen; Ralph, Stephen J

2012-12-01

The microenvironment of a tumor is a highly complex milieu, primarily characterized by immunosuppression, abnormal angiogenesis, and hypoxic regions. These features promote tumor progression and metastasis, resulting in poor prognosis and greater resistance to existing cancer therapies. Galectin-1 is a β-galactoside binding protein that is abundantly secreted by almost all types of malignant tumor cells. The expression of galectin-1 is regulated by hypoxia-inducible factor-1 (HIF-1) and it plays vital pro-tumorigenic roles within the tumor microenvironment. In particular, galectin-1 suppresses T cell-mediated cytotoxic immune responses and promotes tumor angiogenesis. However, since galectin-1 displays many different activities by binding to a number of diverse N- or O-glycan modified target proteins, it has been difficult to fully understand how galectin-1 supports tumor growth and metastasis. This review explores the importance of galectin-1 and glycan expression patterns in the tumor microenvironment and the potential effects of inhibiting galectin-1 as a therapeutic target for cancer treatment.

Accumulation of M1-like macrophages in type 2 diabetic islets is followed by a systemic shift in macrophage polarization.

PubMed

Cucak, Helena; Grunnet, Lars Groth; Rosendahl, Alexander

2014-01-01

Human T2D is characterized by a low-grade systemic inflammation, loss of β-cells, and diminished insulin production. Local islet immunity is still poorly understood, and hence, we evaluated macrophage subpopulations in pancreatic islets in the well-established murine model of T2D, the db/db mouse. Already at 8 weeks of disease, on average, 12 macrophages were observed in the diabetic islets, whereas only two were recorded in the nondiabetic littermates. On a detailed level, the islet resident macrophages increased fourfold compared with nondiabetic littermates, whereas a pronounced recruitment (eightfold) of a novel subset of macrophages (CD68+F4/80-) was observed. The majority of the CD68+F4/80+ but only 40% of the CD68+F4/80- islet macrophages expressed CD11b. Both islet-derived macrophage subsets expressed moderate MHC-II, high galectin-3, and low CD80/CD86 levels, suggesting the cells to be macrophages rather than DCs. On a functional level, the vast majority of the macrophages in the diabetic islets was of the proinflammatory, M1-like phenotype. The systemic immunity in diabetic animals was characterized by a low-grade inflammation with elevated cytokine levels and increase of splenic cytokine, producing CD68+F4/80- macrophages. In late-stage diabetes, the cytokine signature changed toward a TGF-β-dominated profile, coinciding with a significant increase of galectin-3-positive macrophages in the spleen. In summary, our results show that proinflammatory M1-like galectin-3+ CD80/CD86(low) macrophages invade diabetic islets. Moreover, the innate immunity matures in a diabetes-dependent manner from an initial proinflammatory toward a profibrotic phenotype, supporting the concept that T2D is an inflammatory disease.

Cloning, expression, purification and crystallographic studies of galectin-11 from domestic sheep (Ovis aries).

PubMed

Sakthivel, Dhanasekaran; Littler, Dene; Shahine, Adam; Troy, Sally; Johnson, Matthew; Rossjohn, Jamie; Piedrafita, David; Beddoe, Travis

2015-08-01

Galectins are an evolutionarily conserved family of proteins that translate glycan recognition into cellular effects. Galectin-11 is a unique member of the galectin family that is only expressed in ruminants such as sheep, goat and cattle and that plays a critical role in several important biological processes, such as reproduction and parasite-mediated innate immune responses. Currently, these two areas are of major importance for the sustainability of ruminant livestock production. Despite the emerging biological significance of galectin-11, no structural information is available. It is expected that structural studies will unravel the functional mechanisms of galectin-11 activity. Here, the expression, purification and crystallization of the ruminant-specific galectin-11 from domestic sheep and the collection of X-ray data to 2.0 Å resolution are reported.

The genomic structure of the human Charcot-Leyden crystal protein gene is analogous to those of the galectin genes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dyer, K.D.; Handen, J.S.; Rosenberg, H.F.

The Charcot-Leyden crystal (CLC) protein, or eosinophil lysophospholipase, is a characteristic protein of human eosinophils and basophils; recent work has demonstrated that the CLC protein is both structurally and functionally related to the galectin family of {beta}-galactoside binding proteins. The galectins as a group share a number of features in common, including a linear ligand binding site encoded on a single exon. In this work, we demonstrate that the intron-exon structure of the gene encoding CLC is analogous to those encoding the galectins. The coding sequence of the CLC gene is divided into four exons, with the entire {beta}-galactoside bindingmore » site encoded by exon III. We have isolated CLC {beta}-galactoside binding sites from both orangutan (Pongo pygmaeus) and murine (Mus musculus) genomic DNAs, both encoded on single exons, and noted conservation of the amino acids shown to interact directly with the {beta}-galactoside ligand. The most likely interpretation of these results suggests the occurrence of one or more exon duplication and insertion events, resulting in the distribution of this lectin domain to CLC as well as to the multiple galectin genes. 35 refs., 3 figs.« less

Stable and high expression of Galectin-8 tightly controls metastatic progression of prostate cancer

PubMed Central

Gentilini, Lucas Daniel; Pérez, Ignacio González; Kotler, Monica Lidia; Chauchereau, Anne; Laderach, Diego Jose; Compagno, Daniel

2017-01-01

Two decades ago, Galectin-8 was described as a prostate carcinoma biomarker since it is only expressed in the neoplastic prostate, but not in the healthy tissue. To date, no biological function has been attributed to Galectin-8 that could explain this differential expression. In this study we silenced Galectin-8 in two human prostate cancer cell lines, PC3 and IGR-CaP1, and designed a pre-clinical experimental model that allows monitoring the pathology from its early steps to the long-term metastatic stages. We show for the first time that the natural and conserved expression of Gal-8 in tumour cells is responsible for the metastatic evolution of prostate cancer. In fact, Gal-8 controls the rearrangement of the cytoskeleton and E-Cadherin expression, with a major impact on anoikis and homotypic aggregation of tumour cells, both being essential processes for the survival of circulating tumour cells during metastasis. While localized prostate cancer can be cured, metastatic and advanced disease remains a significant therapeutic challenge, urging for the identification of prognostic markers of the metastatic process. Collectively, our results highlight Galectin-8 as a potential target for anti-metastatic therapy against prostate cancer. PMID:28591719

Impact of percutaneous coronary intervention on biomarker levels in patients in the subacute phase following myocardial infarction: the Occluded Artery Trial (OAT) biomarker ancillary study

PubMed Central

2013-01-01

Background The purpose of the Occluded Artery Trial (OAT) Biomarker substudy was to evaluate the impact of infarct related artery (IRA) revascularization on serial levels of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and dynamics of other biomarkers related to left ventricular remodeling, fibrosis and angiogenesis. Methods Patients were eligible for OAT-Biomarker based on the main OAT criteria. Of 70 patients (age 60.8 ± 8.8, 25% women) enrolled in the substudy, 37 were randomized to percutaneous coronary intervention (PCI) and 33 to optimal medical therapy alone. Baseline serum samples were obtained prior to OAT randomization with follow up samples taken at one year. The primary outcome was percent change of NT-proBNP from baseline to 1 year. The secondary outcomes were respective changes of matrix metalloproteinases (MMP) 2 and 9, tissue inhibitor of matrix metalloproteinase 2 (TIMP-2), Vascular Endothelial Growth Factor (VEGF), and Galectin-3. Results Paired (baseline and one-year) serum samples were obtained in 62 subjects. Baseline median NT-proBNP level was 944.8 (455.3, 1533) ng/L and decreased by 69% during follow-up (p < 0.0001). Baseline MMP-2 and TIMP-2 levels increased significantly from baseline to follow-up (p = 0.034, and p = 0.027 respectively), while MMP-9 level decreased from baseline (p = 0.038). Levels of VEGF and Galectin-3 remained stable at one year (p = NS for both). No impact of IRA revascularization on any biomarker dynamics were noted. Conclusions There were significant changes in measured biomarkers related to LV remodeling, stress, and fibrosis following MI between 0 and 12 month. Establishing infarct vessel patency utilizing stenting 24 hours-28 days post MI did not however influence the biomarkers’ release. PMID:24156746

DTU I isolates of Trypanosoma cruzi induce upregulation of Galectin-3 in murine myocarditis and fibrosis.

PubMed

Ferrer, María F; Pascuale, Carla A; Gomez, Ricardo M; Leguizamón, María S

2014-05-01

Chagas heart disease is a major public concern since 30% of infected patients develop cardiac alterations. The relationship between Trypanosoma cruzi discrete typing units (DTUs) and the biological properties exhibited by the parasite population has yet to be elucidated. In this study, we analysed the expression of α-smooth muscle actin (α-SMA) and galectin-3 (Gal-3) associated with cardiac extracellular matrix (ECM) remodelling a murine chronic cardiomyopathy induced by Tc I genotypes. We found the induction of myocarditis was associated with the upregulation of Col I, α-SMA, Gal-3, IFN-γ and IL-13, as analysed by q-PCR. In myocardial areas of fibrosis, the intensity of myocarditis and significant ECM remodelling correlated with the presence of Col I-, Gal-3- and α-SMA-positive cells. These results are promising for the further efforts to evaluate the relevance of Gal-3 in Chagas heart disease, since this galectin was proposed as a prognosis marker in heart failure patients.

Filling in the Gap in Galectin-1 Export

DTIC Science & Technology

2007-09-01

Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT No abstract was provided. 15. SUBJECT TERMS Galectin-1, yeast two hybrid...cell-cell adhesion, cell-extracellular matrix adhesion, and metastasis. Studies indicate that galectins have important roles in cancer as these...Since galectins are important molecules involved in the above-mentioned oncogenic processes, we proposed to identify the molecular mechanisms involved

Targeting galectin-1 inhibits pancreatic cancer progression by modulating tumor-stroma crosstalk.

PubMed

Orozco, Carlos A; Martinez-Bosch, Neus; Guerrero, Pedro E; Vinaixa, Judith; Dalotto-Moreno, Tomás; Iglesias, Mar; Moreno, Mireia; Djurec, Magdolna; Poirier, Françoise; Gabius, Hans-Joachim; Fernandez-Zapico, Martin E; Hwang, Rosa F; Guerra, Carmen; Rabinovich, Gabriel A; Navarro, Pilar

2018-04-17

Pancreatic ductal adenocarcinoma (PDA) remains one of the most lethal tumor types, with extremely low survival rates due to late diagnosis and resistance to standard therapies. A more comprehensive understanding of the complexity of PDA pathobiology, and especially of the role of the tumor microenvironment in disease progression, should pave the way for therapies to improve patient response rates. In this study, we identify galectin-1 (Gal1), a glycan-binding protein that is highly overexpressed in PDA stroma, as a major driver of pancreatic cancer progression. Genetic deletion of Gal1 in a Kras -driven mouse model of PDA ( Ela-Kras G12V p53 -/- ) results in a significant increase in survival through mechanisms involving decreased stroma activation, attenuated vascularization, and enhanced T cell infiltration leading to diminished metastasis rates. In a human setting, human pancreatic stellate cells (HPSCs) promote cancer proliferation, migration, and invasion via Gal1-driven pathways. Moreover, in vivo orthotopic coinjection of pancreatic tumor cells with Gal1-depleted HPSCs leads to impaired tumor formation and metastasis in mice. Gene-expression analyses of pancreatic tumor cells exposed to Gal1 reveal modulation of multiple regulatory pathways involved in tumor progression. Thus, Gal1 hierarchically regulates different events implicated in PDA biology including tumor cell proliferation, invasion, angiogenesis, inflammation, and metastasis, highlighting the broad therapeutic potential of Gal1-specific inhibitors, either alone or in combination with other therapeutic modalities.

Galectin-1 dimers can scaffold Raf-effectors to increase H-ras nanoclustering

PubMed Central

Blaževitš, Olga; Mideksa, Yonatan G.; Šolman, Maja; Ligabue, Alessio; Ariotti, Nicholas; Nakhaeizadeh, Hossein; Fansa, Eyad K.; Papageorgiou, Anastassios C.; Wittinghofer, Alfred; Ahmadian, Mohammad R.; Abankwa, Daniel

2016-01-01

Galectin-1 (Gal-1) dimers crosslink carbohydrates on cell surface receptors. Carbohydrate-derived inhibitors have been developed for cancer treatment. Intracellularly, Gal-1 was suggested to interact with the farnesylated C-terminus of Ras thus specifically stabilizing GTP-H-ras nanoscale signalling hubs in the membrane, termed nanoclusters. The latter activity may present an alternative mechanism for how overexpressed Gal-1 stimulates tumourigenesis. Here we revise the current model for the interaction of Gal-1 with H-ras. We show that it indirectly forms a complex with GTP-H-ras via a high-affinity interaction with the Ras binding domain (RBD) of Ras effectors. A computationally generated model of the Gal-1/C-Raf-RBD complex is validated by mutational analysis. Both cellular FRET as well as proximity ligation assay experiments confirm interaction of Gal-1 with Raf proteins in mammalian cells. Consistently, interference with H-rasG12V-effector interactions basically abolishes H-ras nanoclustering. In addition, an intact dimer interface of Gal-1 is required for it to positively regulate H-rasG12V nanoclustering, but negatively K-rasG12V nanoclustering. Our findings suggest stacked dimers of H-ras, Raf and Gal-1 as building blocks of GTP-H-ras-nanocluster at high Gal-1 levels. Based on our results the Gal-1/effector interface represents a potential drug target site in diseases with aberrant Ras signalling. PMID:27087647

Assessing the stability of free-energy perturbation calculations by performing variations in the method

NASA Astrophysics Data System (ADS)

Manzoni, Francesco; Ryde, Ulf

2018-03-01

We have calculated relative binding affinities for eight tetrafluorophenyl-triazole-thiogalactoside inhibitors of galectin-3 with the alchemical free-energy perturbation approach. We obtain a mean absolute deviation from experimental estimates of only 2-3 kJ/mol and a correlation coefficient (R 2) of 0.5-0.8 for seven relative affinities spanning a range of up to 11 kJ/mol. We also studied the effect of using different methods to calculate the charges of the inhibitor and different sizes of the perturbed group (the atoms that are described by soft-core potentials and are allowed to have differing coordinates). However, the various approaches gave rather similar results and it is not possible to point out one approach as consistently and significantly better than the others. Instead, we suggest that such small and reasonable variations in the computational method can be used to check how stable the calculated results are and to obtain a more accurate estimate of the uncertainty than if performing only one calculation with a single computational setup.

Structure-based rationale for differential recognition of lacto- and neolacto- series glycosphingolipids by the N-terminal domain of human galectin-8

NASA Astrophysics Data System (ADS)

Bohari, Mohammad H.; Yu, Xing; Zick, Yehiel; Blanchard, Helen

2016-12-01

Glycosphingolipids are ubiquitous cell surface molecules undertaking fundamental cellular processes. Lacto-N-tetraose (LNT) and lacto-N-neotetraose (LNnT) are the representative core structures for lacto- and neolacto-series glycosphingolipids. These glycolipids are the carriers to the blood group antigen and human natural killer antigens mainly found on blood cells, and are also principal components in human milk, contributing to infant health. The β-galactoside recognising galectins mediate various cellular functions of these glycosphingolipids. We report crystallographic structures of the galectin-8 N-terminal domain (galectin-8N) in complex with LNT and LNnT. We reveal the first example in which the non-reducing end of LNT binds to the primary binding site of a galectin, and provide a structure-based rationale for the significant ten-fold difference in binding affinities of galectin-8N toward LNT compared to LNnT, such a magnitude of difference not being observed for any other galectin. In addition, the LNnT complex showed that the unique Arg59 has ability to adopt a new orientation, and comparison of glycerol- and lactose-bound galectin-8N structures reveals a minimum atomic framework for ligand recognition. Overall, these results enhance our understanding of glycosphingolipids interactions with galectin-8N, and highlight a structure-based rationale for its significantly different affinity for components of biologically relevant glycosphingolipids.

Immunological tolerance induced by galectin-1 in rat allogeneic renal transplantation.

PubMed

Xu, Gaosi; Tu, Weiping; Xu, Chengyun

2010-06-01

The existed literatures indicated that galectin-1 has anti-inflammatory effects and plays a pivotal role in autoimmune diseases. Present study was to identify the roles of galectin-1 in acute animal renal allograft rejection. Rat acute rejection models were erected by allogeneic renal transplantation. Galectin-1 injection was performed in different concentrations in renal recipients post-transplantation. Recipient survivals, CD8+ T cell proliferation, production of IFN-gamma, levels of serum CD30, enzyme-linked immunoabsorbent spot assay (ELISPOT) and immunohistochemistry were observed or tested 7days after renal transplantation. Galectin-1 injection can prolong the recipient animal survival, reduce the serum levels of IFN-gamma, soluble CD30, percentage of CD8+ T cell subset, CD8+ T cell-mediated cytotoxicity, and IFN-gamma ELISPOT frequency for allograft recipients. The therapeutic effects of galectin-1 injection on recipient rats were dose-dependent. Galectin-1 plays an important role in CD8+ T cell-mediated renal rejection by inducing immunological tolerance. Copyright 2010 Elsevier B.V. All rights reserved.

Timing of Galectin-1 Exposure Differentially Modulates Nipah Virus Entry and Syncytium Formation in Endothelial Cells

PubMed Central

Garner, Omai B.; Yun, Tatyana; Pernet, Olivier; Aguilar, Hector C.; Park, Arnold; Bowden, Thomas A.; Freiberg, Alexander N.

2014-01-01

ABSTRACT Nipah virus (NiV) is a deadly emerging enveloped paramyxovirus that primarily targets human endothelial cells. Endothelial cells express the innate immune effector galectin-1 that we have previously shown can bind to specific N-glycans on the NiV envelope fusion glycoprotein (F). NiV-F mediates fusion of infected endothelial cells into syncytia, resulting in endothelial disruption and hemorrhage. Galectin-1 is an endogenous carbohydrate-binding protein that binds to specific glycans on NiV-F to reduce endothelial cell fusion, an effect that may reduce pathophysiologic sequelae of NiV infection. However, galectins play multiple roles in regulating host-pathogen interactions; for example, galectins can promote attachment of HIV to T cells and macrophages and attachment of HSV-1 to keratinocytes but can also inhibit influenza entry into airway epithelial cells. Using live Nipah virus, in the present study, we demonstrate that galectin-1 can enhance NiV attachment to and infection of primary human endothelial cells by bridging glycans on the viral envelope to host cell glycoproteins. In order to exhibit an enhancing effect, galectin-1 must be present during the initial phase of virus attachment; in contrast, addition of galectin-1 postinfection results in reduced production of progeny virus and syncytium formation. Thus, galectin-1 can have dual and opposing effects on NiV infection of human endothelial cells. While various roles for galectin family members in microbial-host interactions have been described, we report opposing effects of the same galectin family member on a specific virus, with the timing of exposure during the viral life cycle determining the outcome. IMPORTANCE Nipah virus is an emerging pathogen that targets endothelial cells lining blood vessels; the high mortality rate (up to 70%) in Nipah virus infections results from destruction of these cells and resulting catastrophic hemorrhage. Host factors that promote or prevent Nipah virus infection are not well understood. Endogenous human lectins, such as galectin-1, can function as pattern recognition receptors to reduce infection and initiate immune responses; however, lectins can also be exploited by microbes to enhance infection of host cells. We found that galectin-1, which is made by inflamed endothelial cells, can both promote Nipah virus infection of endothelial cells by “bridging” the virus to the cell, as well as reduce production of progeny virus and reduce endothelial cell fusion and damage, depending on timing of galectin-1 exposure. This is the first report of spatiotemporal opposing effects of a host lectin for a virus in one type of host cell. PMID:25505064

Galectin-7 is important for normal uterine repair following menstruation.

PubMed

Evans, Jemma; Yap, Joanne; Gamage, Thillini; Salamonsen, Lois; Dimitriadis, Evdokia; Menkhorst, Ellen

2014-08-01

Menstruation involves the shedding of the functional layer of the endometrium in the absence of pregnancy. At sites where tissue shedding is complete, re-epithelialization of the tissue is essential for repair and termination of bleeding. The complement of growth factors that mediate post-menstrual endometrial repair are yet to be completely elucidated. Galectins regulate many cell functions important for post-menstrual repair, such as cell adhesion and migration. Galectin-7 has a well characterized role in re-epithelialization and wound healing. We hypothesized that galectin-7 would be important in re-epithelialization during post-menstrual repair. We aimed to identify endometrial expression of galectin-7 in women undergoing normal endometrial repair and in women with amenorrhoea who do not experience endometrial breakdown and repair, and to determine whether galectin-7 enhances endometrial re-epithelialization in vitro. Galectin-7 immunolocalized to the endometrial luminal and glandular epithelium during the late secretory and menstrual phases, and to decidualized stroma in regions exhibiting tissue breakdown. Immunostaining intensity was significantly reduced in the endometrium of women with amenorrhoea compared with normally cycling woman. ELISA identified galectin-7 in menstrual fluid at significantly elevated levels compared with matched peripheral plasma. Exogenous galectin-7 (2.5 µg/ml) significantly enhanced endometrial epithelial wound repair in vitro; this was abrogated by inhibition of integrin binding. Galectin-7 elevated epithelial expression of extracellular matrix-related molecules likely involved in repair including β-catenin, contactin and TGF-β1. In conclusion, galectin-7 is produced by the premenstrual and menstrual endometrium, where it accumulates in menstrual fluid and likely acts as a paracrine factor to facilitate post-menstrual endometrial re-epithelialization. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Contrasting acute graft-versus-host disease effects of Tim-3/galectin-9 pathway blockade dependent upon the presence of donor regulatory T cells

PubMed Central

Veenstra, Rachelle G.; Taylor, Patricia A.; Zhou, Qing; Panoskaltsis-Mortari, Angela; Hirashima, Mitsuomi; Flynn, Ryan; Liu, Derek; Anderson, Ana C.; Strom, Terry B.; Kuchroo, Vijay K.

2012-01-01

T-cell immunoglobulin mucin-3 (Tim-3) is expressed on pathogenic T cells, and its ligand galectin-9 (gal-9) is up-regulated in inflamed tissues. When Tim-3+ T cells encounter high gal-9 levels, they are deleted. Tim-3 is up-regulated on activated T cells during GVHD. Inhibition of Tim-3/gal-9 binding by infusion of a Tim-3-Ig fusion protein or Tim-3−/− donor T cells increased T-cell proliferation and GVHD lethality. When the Tim-3/gal-9 pathway engagement was augmented using gal-9 transgenic recipients, GVHD lethality was slowed. Together, these data indicate a potential for modulating this pathway to reduce disease by increasing Tim-3 or gal-9 engagement. Paradoxically, when Tim-3/gal-9 was inhibited in the absence of donor T-regulatory cells (Tregs), GVHD was inhibited. GVHD reduction was associated with decreased colonic inflammatory cytokines as well as epithelial barrier destruction. CD25-depleted Tim-3−/− donor T cells underwent increased activation-induced cell death because of increased IFN-γ production. To our knowledge, these studies are the first to show that although the absence of Tim-3/gal-9 pathway interactions augments systemic GVHD, concurrent donor Treg depletion paradoxically and surprisingly inhibits GVHD. Thus, although donor Tregs typically inhibit GVHD, under some conditions, such Tregs actually may contribute to GVHD by reducing activation-induced T-cell death. PMID:22677125

[Impact of plasma pro-B-type natriuretic peptide amino-terminal and galectin-3 levels on the predictive capacity of the LIPID Clinical Risk Scale in stable coronary disease].

PubMed

Higueras, Javier; Martín-Ventura, José Luis; Blanco-Colio, Luis; Cristóbal, Carmen; Tarín, Nieves; Huelmos, Ana; Alonso, Joaquín; Pello, Ana; Aceña, Álvaro; Carda, Rocío; Lorenzo, Óscar; Mahíllo-Fernández, Ignacio; Asensio, Dolores; Almeida, Pedro; Rodríguez-Artalejo, Fernando; Farré, Jerónimo; López Bescós, Lorenzo; Egido, Jesús; Tuñón, José

2015-01-01

At present, there is no tool validated by scientific societies for risk stratification of patients with stable coronary artery disease (SCAD). It has been shown that plasma levels of monocyte chemoattractant protein-1 (MCP-1), galectin-3 and pro-B-type natriuretic peptide amino-terminal (NT-proBNP) have prognostic value in this population. To analyze the prognostic value of a clinical risk scale published in Long-term Intervention with Pravastatin in Ischemic Disease (LIPID) study and determining its predictive capacity when combined with plasma levels of MCP-1, galectin-3 and NT-proBNP in patients with SCAD. A total of 706 patients with SCAD and a history of acute coronary syndrome (ACS) were analyzed over a follow up period of 2.2 ± 0.99 years. The primary endpoint was the occurrence of an ischemic event (any SCA, stroke or transient ischemic attack), heart failure, or death. A clinical risk scale derived from the LIPID study significantly predicted the development of the primary endpoint, with an area under the ROC curve (Receiver Operating Characteristic) of 0.642 (0.579 to 0.705); P<0.001. A composite score was developed by adding the scores of the LIPID and scale decile levels of MCP -1, galectin -3 and NT-proBNP. The predictive value improved with an area under the curve of 0.744 (0.684 to 0.805); P<0.001 (P=0.022 for comparison). A score greater than 21.5 had a sensitivity of 74% and a specificity of 61% for the development of the primary endpoint (P<0.001, log -rank test). Plasma levels of MCP-1, galectin -3 and NT-proBNP improve the ability of the LIPID clinical scale to predict the prognosis of patients with SCAD. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

Crystallization and preliminary X-ray diffraction analysis of mouse galectin-4 N-terminal carbohydrate recognition domain in complex with lactose

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krejčiříková, Veronika; Fábry, Milan; Marková, Vladimíra

2008-07-01

Mouse galectin-4 carbohydrate binding domain was overexpressed in E. coli and crystallized in the presence of lactose. The crystals belong to tetragonal space group P42{sub 1}2 and diffraction data were collected to 2.1 Å resolution. Galectin-4 is thought to play a role in the process of tumour conversion of cells of the alimentary tract and the breast tissue; however, its exact function remains unknown. With the aim of elucidating the structural basis of mouse galectin-4 (mGal-4) binding specificity, we have undertaken X-ray analysis of the N-terminal domain, CRD1, of mGal-4 in complex with lactose (the basic building block of knownmore » galectin-4 carbohydrate ligands). Crystals of CRD1 in complex with lactose were obtained using vapour-diffusion techniques. The crystals belong to tetragonal space group P42{sub 1}2 with unit-cell parameters a = 91.1, b = 91.16, c = 57.10 Å and preliminary X-ray diffraction data were collected to 3.2 Å resolution. An optimized crystallization procedure and cryocooling protocol allowed us to extend resolution to 2.1 Å. Structure refinement is currently under way; the initial electron-density maps clearly show non-protein electron density in the vicinity of the carbohydrate binding site, indicating the presence of one lactose molecule. The structure will help to improve understanding of the binding specificity and function of the potential colon cancer marker galectin-4.« less

Galectins: Double-edged Swords in the Cross-roads of Pregnancy Complications and Female Reproductive Tract Inflammation and Neoplasia.

PubMed

Than, Nandor Gabor; Romero, Roberto; Balogh, Andrea; Karpati, Eva; Mastrolia, Salvatore Andrea; Staretz-Chacham, Orna; Hahn, Sinuhe; Erez, Offer; Papp, Zoltan; Kim, Chong Jai

2015-05-01

Galectins are an evolutionarily ancient and widely expressed family of lectins that have unique glycan-binding characteristics. They are pleiotropic regulators of key biological processes, such as cell growth, proliferation, differentiation, apoptosis, signal transduction, and pre-mRNA splicing, as well as homo- and heterotypic cell-cell and cell-extracellular matrix interactions. Galectins are also pivotal in immune responses since they regulate host-pathogen interactions, innate and adaptive immune responses, acute and chronic inflammation, and immune tolerance. Some galectins are also central to the regulation of angiogenesis, cell migration and invasion. Expression and functional data provide convincing evidence that, due to these functions, galectins play key roles in shared and unique pathways of normal embryonic and placental development as well as oncodevelopmental processes in tumorigenesis. Therefore, galectins may sometimes act as double-edged swords since they have beneficial but also harmful effects for the organism. Recent advances facilitate the use of galectins as biomarkers in obstetrical syndromes and in various malignancies, and their therapeutic applications are also under investigation. This review provides a general overview of galectins and a focused review of this lectin subfamily in the context of inflammation, infection and tumors of the female reproductive tract as well as in normal pregnancies and those complicated by the great obstetrical syndromes.

Regulation of ozone-induced lung inflammation and injury by the β-galactoside-binding lectin galectin-3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sunil, Vasanthi R., E-mail: sunilva@pharmacy.rutgers.edu; Francis, Mary, E-mail: maryfranrutgers@gmail.com; Vayas, Kinal N., E-mail: kinalv5@gmail.com

Macrophages play a dual role in ozone toxicity, contributing to both pro- and anti-inflammatory processes. Galectin-3 (Gal-3) is a lectin known to regulate macrophage activity. Herein, we analyzed the role of Gal-3 in the response of lung macrophages to ozone. Bronchoalveolar lavage (BAL) and lung tissue were collected 24–72 h after exposure (3 h) of WT and Gal-3{sup -/-} mice to air or 0.8 ppm ozone. In WT mice, ozone inhalation resulted in increased numbers of proinflammatory (Gal-3{sup +}, iNOS{sup +}) and anti-inflammatory (MR-1{sup +}) macrophages in the lungs. While accumulation of iNOS{sup +} macrophages was attenuated in Gal-3{sup -/-}more » mice, increased numbers of enlarged MR-1{sup +} macrophages were noted. This correlated with increased numbers of macrophages in BAL. Flow cytometric analysis showed that these cells were CD11b{sup +} and consisted mainly (> 97%) of mature (F4/80{sup +}CD11c{sup +}) proinflammatory (Ly6GLy6C{sup hi}) and anti-inflammatory (Ly6GLy6C{sup lo}) macrophages. Increases in both macrophage subpopulations were observed following ozone inhalation. Loss of Gal-3 resulted in a decrease in Ly6C{sup hi} macrophages, with no effect on Ly6C{sup lo} macrophages. CD11b{sup +}Ly6G{sup +}Ly6C{sup +} granulocytic (G) and monocytic (M) myeloid derived suppressor cells (MDSC) were also identified in the lung after ozone. In Gal-3{sup -/-} mice, the response of G-MDSC to ozone was attenuated, while the response of M-MDSC was heightened. Changes in inflammatory cell populations in the lung of ozone treated Gal-3{sup -/-} mice were correlated with reduced tissue injury as measured by cytochrome b5 expression. These data demonstrate that Gal-3 plays a role in promoting proinflammatory macrophage accumulation and toxicity in the lung following ozone exposure. - Highlights: • Multiple monocytic-macrophage subpopulations accumulate in the lung after ozone inhalation. • Galectin-3 plays a proinflammatory role in ozone-induced lung injury. • In the absence of gal-3, inflammatory cells with a myeloid derived suppressor cell phenotype contribute to tissue repair.« less

Immunomodulatory Factors Galectin-9 and Interferon-Gamma Synergize to Induce Expression of Rate-Limiting Enzymes of the Kynurenine Pathway in the Mouse Hippocampus

PubMed Central

Brooks, Alexandra K.; Lawson, Marcus A.; Rytych, Jennifer L.; Yu, Kevin C.; Janda, Tiffany M.; Steelman, Andrew J.; McCusker, Robert H.

2016-01-01

Elevated levels of circulating pro-inflammatory cytokines are associated with symptomology of several psychiatric disorders, notably major depressive disorder. Symptomology has been linked to inflammation/cytokine-dependent induction of the Kynurenine Pathway. Galectins, like pro-inflammatory cytokines, play a role in neuroinflammation and the pathogenesis of several neurological disorders but without a clearly defined mechanism of action. Their involvement in the Kynurenine Pathway has not been investigated. Thus, we searched for a link between galectins and the Kynurenine Pathway using in vivo and ex vivo models. Mice were administered LPS and pI:C to determine if galectins (Gal’s) were upregulated in the brain following in vivo inflammatory challenges. We then used organotypic hippocampal slice cultures (OHSCs) to determine if Gal’s, alone or with inflammatory mediators [interferon-gamma (IFNγ), tumor necrosis factor-alpha (TNFα), interleukin-1beta (IL-1β), polyinosine-polycytidylic acid (pI:C), and dexamethasone (Dex; synthetic glucocorticoid)], would increase expression of indoleamine/tryptophan-2,3-dioxygenases (DO’s: Ido1, Ido2, and Tdo2; Kynurenine Pathway rate-limiting enzymes). In vivo, hippocampal expression of cytokines (IL-1β, TNFα, and IFNγ), Gal-3, and Gal-9 along with Ido1 and Ido2 were increased by LPS and pI:C (bacterial and viral mimetics). Of the cytokines induced in vivo, only IFNγ increased expression of two Ido1 transcripts (Ido1-FL and Ido1-v1) by OHSCs. Although ineffective alone, Gal-9 accentuated IFNγ-induced expression of only Ido1-FL. Similarly, IFNγ induced expression of several Ido2 transcripts (Ido2-v1, Ido2-v3, Ido2-v4, Ido2-v5, and Ido2-v6). Gal-9 accentuated IFNγ-induced expression of only Ido2-v1. Surprisingly, Gal-9 alone, slightly but significantly, induced expression of Tdo2 (Tdo2-v1 and Tdo2-v2, but not Tdo2-FL). These effects were specific to Gal-9 as Gal-1 and Gal-3 did not alter DO expression. These results are the first to show that brain Gal-9 is increased during LPS- and pI:C-induced neuroinflammation. Increased expression of Gal-9 may be critical for neuroinflammation-dependent induction of DO expression, either acting alone (Tdo2-v1 and Tdo2-v2) or to enhance IFNγ activity (Ido1-FL and Ido2-v1). Although these novel actions of Gal-9 are described for hippocampus, they have the potential to operate as DO-dependent immunomodulatory processes outside the brain. With the expanding implications of Kynurenine Pathway activation across multiple immune and psychiatric disorders, this synergy provides a new target for therapeutic development. PMID:27799931

Endothelial Galectin-1 Binds to Specific Glycans on Nipah Virus Fusion Protein and Inhibits Maturation, Mobility, and Function to Block Syncytia Formation

PubMed Central

Garner, Omai B.; Aguilar, Hector C.; Fulcher, Jennifer A.; Levroney, Ernest L.; Harrison, Rebecca; Wright, Lacey; Robinson, Lindsey R.; Aspericueta, Vanessa; Panico, Maria; Haslam, Stuart M.; Morris, Howard R.; Dell, Anne

2010-01-01

Nipah virus targets human endothelial cells via NiV-F and NiV-G envelope glycoproteins, resulting in endothelial syncytia formation and vascular compromise. Endothelial cells respond to viral infection by releasing innate immune effectors, including galectins, which are secreted proteins that bind to specific glycan ligands on cell surface glycoproteins. We demonstrate that galectin-1 reduces NiV-F mediated fusion of endothelial cells, and that endogenous galectin-1 in endothelial cells is sufficient to inhibit syncytia formation. Galectin-1 regulates NiV-F mediated cell fusion at three distinct points, including retarding maturation of nascent NiV-F, reducing NiV-F lateral mobility on the plasma membrane, and directly inhibiting the conformational change in NiV-F required for triggering fusion. Characterization of the NiV-F N-glycome showed that the critical site for galectin-1 inhibition is rich in glycan structures known to bind galectin-1. These studies identify a unique set of mechanisms for regulating pathophysiology of NiV infection at the level of the target cell. PMID:20657665

Vascular dysfunction and fibrosis in stroke-prone spontaneously hypertensive rats: The aldosterone-mineralocorticoid receptor-Nox1 axis.

PubMed

Harvey, Adam P; Montezano, Augusto C; Hood, Katie Y; Lopes, Rheure A; Rios, Francisco; Ceravolo, Graziela; Graham, Delyth; Touyz, Rhian M

2017-06-15

We questioned whether aldosterone and oxidative stress play a role in vascular damage in severe hypertension and investigated the role of Nox1 in this process. We studied mesenteric arteries, aortas and vascular smooth muscle cells (VSMC) from WKY and SHRSP rats. Vascular effects of eplerenone or canrenoic acid (CA) (mineralocorticoid receptor (MR) blockers), ML171 (Nox1 inhibitor) and EHT1864 (Rac1/2 inhibitor) were assessed. Nox1-knockout mice were also studied. Vessels and VSMCs were probed for Noxs, reactive oxygen species (ROS) and pro-fibrotic/inflammatory signaling. Blood pressure and plasma levels of aldosterone and galectin-3 were increased in SHRSP versus WKY. Acetylcholine-induced vasorelaxation was decreased (61% vs 115%) and phenylephrine-induced contraction increased in SHRSP versus WKY (E max 132.8% vs 96.9%, p<0.05). Eplerenone, ML171 and EHT1864 attenuated hypercontractility in SHRSP. Vascular expression of collagen, fibronectin, TGFβ, MCP-1, RANTES, MMP2, MMP9 and p66Shc was increased in SHRSP versus WKY. These changes were associated with increased ROS generation, 3-nitrotyrosine expression and Nox1 upregulation. Activation of vascular p66Shc and increased expression of Nox1 and collagen I were prevented by CA in SHRSP. Nox1 expression was increased in aldosterone-stimulated WKY VSMCs, an effect that was amplified in SHRSP VSMCs (5.2vs9.9 fold-increase). ML171 prevented aldosterone-induced VSMC Nox1-ROS production. Aldosterone increased vascular expression of fibronectin and PAI-1 in wild-type mice but not in Nox1-knockout mice. Our findings suggest that aldosterone, which is increased in SHRSP, induces vascular damage through MR-Nox1-p66Shc-mediated processes that modulate pro-fibrotic and pro-inflammatory signaling pathways. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Peptides derived from human galectin-3 N-terminal tail interact with its carbohydrate recognition domain in a phosphorylation-dependent manner

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berbís, M. Álvaro; André, Sabine; Cañada, F. Javier

2014-01-03

Highlights: •Galectin-3 is composed of a carbohydrate recognition domain and an N-terminal tail. •Synthetic peptides derived from the tail are shown to interact with the CRD. •This interaction is modulated by Ser- and Tyr-phosphorylation of the peptides. -- Abstract: Galectin-3 (Gal-3) is a multi-functional effector protein that functions in the cytoplasm and the nucleus, as well as extracellularly following non-classical secretion. Structurally, Gal-3 is unique among galectins with its carbohydrate recognition domain (CRD) attached to a rather long N-terminal tail composed mostly of collagen-like repeats (nine in the human protein) and terminating in a short non-collagenous terminal peptide sequence uniquemore » in this lectin family and not yet fully explored. Although several Ser and Tyr sites within the N-terminal tail can be phosphorylated, the physiological significance of this post-translational modification remains unclear. Here, we used a series of synthetic (phospho)peptides derived from the tail to assess phosphorylation-mediated interactions with {sup 15}N-labeled Gal-3 CRD. HSQC-derived chemical shift perturbations revealed selective interactions at the backface of the CRD that were attenuated by phosphorylation of Tyr 107 and Tyr 118, while phosphorylation of Ser 6 and Ser 12 was essential. Controls with sequence scrambling underscored inherent specificity. Our studies shed light on how phosphorylation of the N-terminal tail may impact on Gal-3 function and prompt further studies using phosphorylated full-length protein.« less

Galectin-9-CD44 interaction enhances stability and function of adaptive regulatory T cells | Center for Cancer Research

Cancer.gov

The β-galactoside-binding protein galectin-9 is critical in regulating the immune response, but the mechanism by which it functions remains unclear. We have demonstrated that galectin-9 is highly expressed by induced regulatory T cells (iTreg) and was crucial for the generation and function of iTreg cells, but not natural regulatory T (nTreg) cells. Galectin-9 expression

Timing of galectin-1 exposure differentially modulates Nipah virus entry and syncytium formation in endothelial cells.

PubMed

Garner, Omai B; Yun, Tatyana; Pernet, Olivier; Aguilar, Hector C; Park, Arnold; Bowden, Thomas A; Freiberg, Alexander N; Lee, Benhur; Baum, Linda G

2015-03-01

Nipah virus (NiV) is a deadly emerging enveloped paramyxovirus that primarily targets human endothelial cells. Endothelial cells express the innate immune effector galectin-1 that we have previously shown can bind to specific N-glycans on the NiV envelope fusion glycoprotein (F). NiV-F mediates fusion of infected endothelial cells into syncytia, resulting in endothelial disruption and hemorrhage. Galectin-1 is an endogenous carbohydrate-binding protein that binds to specific glycans on NiV-F to reduce endothelial cell fusion, an effect that may reduce pathophysiologic sequelae of NiV infection. However, galectins play multiple roles in regulating host-pathogen interactions; for example, galectins can promote attachment of HIV to T cells and macrophages and attachment of HSV-1 to keratinocytes but can also inhibit influenza entry into airway epithelial cells. Using live Nipah virus, in the present study, we demonstrate that galectin-1 can enhance NiV attachment to and infection of primary human endothelial cells by bridging glycans on the viral envelope to host cell glycoproteins. In order to exhibit an enhancing effect, galectin-1 must be present during the initial phase of virus attachment; in contrast, addition of galectin-1 postinfection results in reduced production of progeny virus and syncytium formation. Thus, galectin-1 can have dual and opposing effects on NiV infection of human endothelial cells. While various roles for galectin family members in microbial-host interactions have been described, we report opposing effects of the same galectin family member on a specific virus, with the timing of exposure during the viral life cycle determining the outcome. Nipah virus is an emerging pathogen that targets endothelial cells lining blood vessels; the high mortality rate (up to 70%) in Nipah virus infections results from destruction of these cells and resulting catastrophic hemorrhage. Host factors that promote or prevent Nipah virus infection are not well understood. Endogenous human lectins, such as galectin-1, can function as pattern recognition receptors to reduce infection and initiate immune responses; however, lectins can also be exploited by microbes to enhance infection of host cells. We found that galectin-1, which is made by inflamed endothelial cells, can both promote Nipah virus infection of endothelial cells by "bridging" the virus to the cell, as well as reduce production of progeny virus and reduce endothelial cell fusion and damage, depending on timing of galectin-1 exposure. This is the first report of spatiotemporal opposing effects of a host lectin for a virus in one type of host cell. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Quantitation and histochemical localization of galectin-1 and galectin-1-reactive glycoconjugates in fetal development of bovine organs.

PubMed

Kaltner, H; Lips, K S; Reuter, G; Lippert, S; Sinowatz, F; Gabius, H J

1997-10-01

The display of cellular oligosaccharide chains is known to undergo marked developmental changes, as monitored histochemically with plant lectins. In conjunction with endogenous lectins respective ligand structures may have a functional role during fetal development. The assumption of a recognitive, functionally productive interplay prompts the study of the expression of a tissue lectin and of lectin-reactive glycoconjugates concomitantly. Focusing on common beta-galactosides as constituents of oligosaccharide chains and the predominant member of the family of galectins in mammals, namely galectin-1, the question therefore is addressed as to whether expression of lectin and lectin-reactive glycoconjugates exhibits alterations, assessed in three morphologically defined fetal stages and in adult bovine organs. Using a sandwich ELISA, the level of the rather ubiquitous galectin-1 is mostly increased in adult organs relative to respective fetal stages, except for the case of kidney. This developmental course is seen rather seldom, when the amounts of lectin-reactive glycoproteins or glycolipids are quantitated in solid-phase assays after tissue homogenization. Western blotting, combined with probing by labeled galectin-1, discloses primarily quantitative changes in the reactivity of individual glycoproteins. Performing the same assays on extract aliquots with a plant agglutinin, namely the galactoside-binding mistletoe lectin, whose fine specificity is different from galectin-1, its reduced extent of binding in solid-phase assays and the disparate profile of lectin-reactive glycoproteins reveal a non-uniform developmental alteration within the group of structural variants of beta-galactosides. Although sample preparation can affect ligand preservation and/or presentation and thus restricts the comparability of biochemical and histochemical results, especially for soluble reactants, the histochemical studies on frozen and paraffin-embedded sections of bovine heart, kidney and liver demonstrate that the localization of the galectin and of lectin-reactive epitopes can show a similar distribution, as seen in liver and heart, with organ-typical quantitative changes of a rather similar staining profile (heart, kidney) or notable changes in the spatial distribution (liver) in the course of development. This report emphasizes the potential value of combined monitoring of the lectin and its potential in vivo ligands to contribute to eventually unravel organ-related function(s) of a tissue lectin.

How galectin-3 changes acute heart failure decision making in the emergency department.

PubMed

Peacock, W Frank

2014-10-01

When considering the appropriate disposition plan in a patient presenting to the emergency department (ED) with acute heart failure (HF), the range of options includes discharge home to intensive care unit (ICU) admission. Unfortunately, there are few objective measures to insure optimal choices, and the currently available science is scant at best. The consequences of a lack of a standardized approach are nowhere more evident than as demonstrated by the worldwide 90-day heart failure rehospitalization rate that exceeds 25%. New strategies to address this important gap in clinical care are sorely needed. The measurement of galectin-3 may represent a new alternative to the historical standard of gestalt-based clinical disposition decisions. Elevated galectin-3 can identify patients at very high risk for short-term adverse outcomes, while low levels identify a population with essentially no 90-day revisits. This prospective objective measure of illness severity may aid in clinical decision making and thus represent a future where rehospitalization after HF is an unusual event.

Galectin-3 and IL-33/ST2 axis roles and interplay in diet-induced steatohepatitis

PubMed Central

Pejnovic, Nada; Jeftic, Ilija; Jovicic, Nemanja; Arsenijevic, Nebojsa; Lukic, Miodrag L

2016-01-01

Immune reactivity and chronic low-grade inflammation (metaflammation) play an important role in the pathogenesis of obesity-associated metabolic disorders, including type 2 diabetes and nonalcoholic fatty liver disease (NAFLD), a spectrum of diseases that include liver steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. Increased adiposity and insulin resistance contribute to the progression from hepatic steatosis to NASH and fibrosis through the development of proinflammatory and profibrotic processes in the liver, including increased hepatic infiltration of innate and adaptive immune cells, altered balance of cytokines and chemokines, increased reactive oxygen species generation and hepatocellular death. Experimental models of dietary-induced NAFLD/NASH in mice on different genetic backgrounds or knockout mice with different immune reactivity are used for elucidating the pathogenesis of NASH and liver fibrosis. Galectin-3 (Gal-3), a unique chimera-type β-galactoside-binding protein of the galectin family has a regulatory role in immunometabolism and fibrogenesis. Mice deficient in Gal-3 develop pronounced adiposity, hyperglycemia and hepatic steatosis, as well as attenuated liver inflammation and fibrosis when fed an obesogenic high-fat diet. Interleukin (IL)-33, a member of the IL-1 cytokine family, mediates its effects through the ST receptor, which is present on immune and nonimmune cells and participates in immunometabolic and fibrotic disorders. Recent evidence, including our own data, suggests a protective role for the IL-33/IL-33R (ST2) signaling pathway in obesity, adipose tissue inflammation and atherosclerosis, but a profibrotic role in NASH development. The link between Gal-3 and soluble ST2 in myocardial fibrosis and heart failure progression has been demonstrated and we have recently shown that Gal-3 and the IL-33/ST2 pathway interact and both have a profibrotic role in diet-induced NASH. This review discusses the current evidence on the roles of Gal-3 and the IL-33/ST2 pathway and their interplay in obesity-associated hepatic inflammation and fibrogenesis that may be of interest in the development of therapeutic interventions to prevent and/or reverse obesity-associated hepatic inflammation and fibrosis. PMID:27956794

The epithelial polarity regulator LGALS9/galectin-9 induces fatal frustrated autophagy in KRAS mutant colon carcinoma that depends on elevated basal autophagic flux

PubMed Central

Wiersma, Valerie R; de Bruyn, Marco; Wei, Yunwei; van Ginkel, Robert J; Hirashima, Mitsuomi; Niki, Toshiro; Nishi, Nozomu; Zhou, Jin; Pouwels, Simon D; Samplonius, Douwe F; Nijman, Hans W; Eggleton, Paul; Helfrich, Wijnand; Bremer, Edwin

2015-01-01

Oncogenic mutation of KRAS (Kirsten rat sarcoma viral oncogene homolog) in colorectal cancer (CRC) confers resistance to both chemotherapy and EGFR (epidermal growth factor receptor)-targeted therapy. We uncovered that KRAS mutant (KRASmut) CRC is uniquely sensitive to treatment with recombinant LGALS9/Galectin-9 (rLGALS9), a recently established regulator of epithelial polarity. Upon treatment of CRC cells, rLGALS9 rapidly internalizes via early- and late-endosomes and accumulates in the lysosomal compartment. Treatment with rLGALS9 is accompanied by induction of frustrated autophagy in KRASmut CRC, but not in CRC with BRAF (B-Raf proto-oncogene, serine/threonine kinase) mutations (BRAFmut). In KRASmut CRC, rLGALS9 acts as a lysosomal inhibitor that inhibits autophagosome-lysosome fusion, leading to autophagosome accumulation, excessive lysosomal swelling and cell death. This antitumor activity of rLGALS9 directly correlates with elevated basal autophagic flux in KRASmut cancer cells. Thus, rLGALS9 has potent antitumor activity toward refractory KRASmut CRC cells that may be exploitable for therapeutic use. PMID:26086204

Galectins: Double-edged Swords in the Cross-roads of Pregnancy Complications and Female Reproductive Tract Inflammation and Neoplasia

PubMed Central

Than, Nandor Gabor; Romero, Roberto; Balogh, Andrea; Karpati, Eva; Mastrolia, Salvatore Andrea; Staretz-Chacham, Orna; Hahn, Sinuhe; Erez, Offer; Papp, Zoltan; Kim, Chong Jai

2015-01-01

Galectins are an evolutionarily ancient and widely expressed family of lectins that have unique glycan-binding characteristics. They are pleiotropic regulators of key biological processes, such as cell growth, proliferation, differentiation, apoptosis, signal transduction, and pre-mRNA splicing, as well as homo- and heterotypic cell-cell and cell-extracellular matrix interactions. Galectins are also pivotal in immune responses since they regulate host-pathogen interactions, innate and adaptive immune responses, acute and chronic inflammation, and immune tolerance. Some galectins are also central to the regulation of angiogenesis, cell migration and invasion. Expression and functional data provide convincing evidence that, due to these functions, galectins play key roles in shared and unique pathways of normal embryonic and placental development as well as oncodevelopmental processes in tumorigenesis. Therefore, galectins may sometimes act as double-edged swords since they have beneficial but also harmful effects for the organism. Recent advances facilitate the use of galectins as biomarkers in obstetrical syndromes and in various malignancies, and their therapeutic applications are also under investigation. This review provides a general overview of galectins and a focused review of this lectin subfamily in the context of inflammation, infection and tumors of the female reproductive tract as well as in normal pregnancies and those complicated by the great obstetrical syndromes. PMID:26018511

Galectins in Intestinal Inflammation: Galectin-1 Expression Delineates Response to Treatment in Celiac Disease Patients

PubMed Central

Sundblad, Victoria; Quintar, Amado A.; Morosi, Luciano G.; Niveloni, Sonia I.; Cabanne, Ana; Smecuol, Edgardo; Mauriño, Eduardo; Mariño, Karina V.; Bai, Julio C.; Maldonado, Cristina A.; Rabinovich, Gabriel A.

2018-01-01

Galectins, a family of animal lectins characterized by their affinity for N-acetyllactosamine-enriched glycoconjugates, modulate several immune cell processes shaping the course of innate and adaptive immune responses. Through interaction with a wide range of glycosylated receptors bearing complex branched N-glycans and core 2-O-glycans, these endogenous lectins trigger distinct signaling programs thereby controling immune cell activation, differentiation, recruitment and survival. Given the unique features of mucosal inflammation and the differential expression of galectins throughout the gastrointestinal tract, we discuss here key findings on the role of galectins in intestinal inflammation, particularly Crohn’s disease, ulcerative colitis, and celiac disease (CeD) patients, as well as in murine models resembling these inflammatory conditions. In addition, we present new data highlighting the regulated expression of galectin-1 (Gal-1), a proto-type member of the galectin family, during intestinal inflammation in untreated and treated CeD patients. Our results unveil a substantial upregulation of Gal-1 accompanying the anti-inflammatory and tolerogenic response associated with gluten-free diet in CeD patients, suggesting a major role of this lectin in favoring resolution of inflammation and restoration of mucosal homeostasis. Thus, a coordinated network of galectins and their glycosylated ligands, exerting either anti-inflammatory or proinflammatory responses, may influence the interplay between intestinal epithelial cells and the highly specialized gut immune system in physiologic and pathologic settings. PMID:29545799

Galectins in Intestinal Inflammation: Galectin-1 Expression Delineates Response to Treatment in Celiac Disease Patients.

PubMed

Sundblad, Victoria; Quintar, Amado A; Morosi, Luciano G; Niveloni, Sonia I; Cabanne, Ana; Smecuol, Edgardo; Mauriño, Eduardo; Mariño, Karina V; Bai, Julio C; Maldonado, Cristina A; Rabinovich, Gabriel A

2018-01-01

Galectins, a family of animal lectins characterized by their affinity for N-acetyllactosamine-enriched glycoconjugates, modulate several immune cell processes shaping the course of innate and adaptive immune responses. Through interaction with a wide range of glycosylated receptors bearing complex branched N-glycans and core 2-O-glycans, these endogenous lectins trigger distinct signaling programs thereby controling immune cell activation, differentiation, recruitment and survival. Given the unique features of mucosal inflammation and the differential expression of galectins throughout the gastrointestinal tract, we discuss here key findings on the role of galectins in intestinal inflammation, particularly Crohn's disease, ulcerative colitis, and celiac disease (CeD) patients, as well as in murine models resembling these inflammatory conditions. In addition, we present new data highlighting the regulated expression of galectin-1 (Gal-1), a proto-type member of the galectin family, during intestinal inflammation in untreated and treated CeD patients. Our results unveil a substantial upregulation of Gal-1 accompanying the anti-inflammatory and tolerogenic response associated with gluten-free diet in CeD patients, suggesting a major role of this lectin in favoring resolution of inflammation and restoration of mucosal homeostasis. Thus, a coordinated network of galectins and their glycosylated ligands, exerting either anti-inflammatory or proinflammatory responses, may influence the interplay between intestinal epithelial cells and the highly specialized gut immune system in physiologic and pathologic settings.

Cyclin D1 in well differentiated thyroid tumour of uncertain malignant potential.

PubMed

Lamba Saini, Monika; Weynand, Birgit; Rahier, Jacques; Mourad, Michel; Hamoir, Marc; Marbaix, Etienne

2015-04-18

Encapsulated follicular tumours with equivocal papillary thyroid carcinoma (PTC) type nuclear features continue to remain a challenge despite the recent attempts to classify these borderline lesions. The term 'well differentiated tumour of uncertain malignant potential (WDT-UMP)' was introduced to classify these tumours. The present study aimed to evaluate the role of a cell cycle regulator like cyclin D1 in these tumours along with assessment of other well established PTC markers like galectin-3, HBME-1, CK19. Thirteen cases of metastatic PTC, papillary microcarcinoma and follicular variant of PTC (FVPTC) were identified from a histological review of 510 cases. In addition, 13 cases of a subset of follicular adenomatoid nodules with focal areas showing nuclear features characteristic of PTC, identified as WDT-UMP, were also analyzed. Immunohistochemical analysis of galectin-3, HBME-1, CK19 and the proliferation markers Ki67 and cyclin D1 was performed. Lesions were analyzed for cyclin D1 gene amplification by fluorescent in-situ hybridization. All WDT-UMP lesions showed immunolabelling of cyclin D1, Ki67; 11/ 13 cases showed immunolabelling of CK19; 10/13 cases showed immunolabelling of HBME-1 and 4/13 cases showed immunolabelling of galectin-3. Surrounding benign adenomatoid areas showed no to faint focal staining in all thirteen cases of cyclin D1, HBME-1 and galectin-3. A low rate of cyclin D1 gene amplification was identified in a significant proportion of cells in the WDT-UMP lesions as compared to surrounding benign adenomatoid areas. Increased expression of cyclin D1 and amplification of its gene along with immunolabelling of HBME-1 in WDT-UMP lesions showing cytological features of papillary thyroid carcinoma within follicular adenomatoid nodules suggest that these areas could correspond to a precursor lesion of follicular variant of PTC. Overexpression of cyclin D1, associated with the amplification of the gene suggests that these WDT-UMP lesions are an intermediate between the benign and malignant groups making this group of lesions a reliable precursor of FVPTC. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1851820807142117.

Biomarkers and low risk in heart failure. Data from COACH and TRIUMPH.

PubMed

Meijers, Wouter C; de Boer, Rudolf A; van Veldhuisen, Dirk J; Jaarsma, Tiny; Hillege, Hans L; Maisel, Alan S; Di Somma, Salvatore; Voors, Adriaan A; Peacock, W Frank

2015-12-01

Traditionally, risk stratification in heart failure (HF) emphasizes assessment of high risk. We aimed to determine if biomarkers could identify patients with HF at low risk for death or HF rehospitalization. This analysis was a substudy of The Coordinating Study Evaluating Outcomes of Advising and Counselling in Heart Failure (COACH) trial. Enrolment of HF patients occurred before discharge. We defined low risk as the absence of death and/or HF rehospitalizations at 180 days. We tested a diverse group of 29 biomarkers on top of a clinical risk model, with and without N-terminal pro-B-type natriuretic peptide (NT-proBNP), and defined the low risk biomarker cut-off at the 10th percentile associated with high positive predictive value. The best performing biomarkers together with NT-proBNP and cardiac troponin I (cTnI) were re-evaluated in a validation cohort of 285 HF patients. Of 592 eligible COACH patients, the mean (± SD) age was 71 (± 11) years and median (IQR) NT-proBNP was 2521 (1301-5634) pg/mL. Logistic regression analysis showed that only galectin-3, fully adjusted, was significantly associated with the absence of events at 180 days (OR 8.1, 95% confidence interval 1.06-50.0, P = 0.039). Galectin-3, showed incremental value when added to the clinical risk model without NT-proBNP (increase in area under the curve from 0.712 to 0.745, P = 0.04). However, no biomarker showed significant improvement by net reclassification improvement on top of the clinical risk model, with or without NT-proBNP. We confirmed our results regarding galectin-3, NT-proBNP, and cTnI in the independent validation cohort. We describe the value of various biomarkers to define low risk, and demonstrate that galectin-3 identifies HF patients at (very) low risk for 30-day and 180-day mortality and HF rehospitalizations after an episode of acute HF. Such patients might be safely discharged. © 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiolog.

Structural, functional, and evolutionary aspects of galectins in aquatic mollusks: From a sweet tooth to the Trojan horse

PubMed Central

Vasta, GR; Feng, C; Bianchet, MA; Bachvaroff, TR; Tasumi, S

2015-01-01

Galectins constitute a conserved and widely distributed lectin family characterized by their binding affinity for β-galactosides and a unique binding site sequence motif in the carbohydrate recognition domain (CRD). In spite of their structural conservation, galectins display a remarkable functional diversity, by participating in developmental processes, cell adhesion and motility, regulation of immune homeostasis, and recognition of glycans on the surface of viruses, bacteria and protozoan parasites. In contrast with mammals, and other vertebrate and invertebrate taxa, the identification and characterization of bona fide galectins in aquatic mollusks has been relatively recent. Most of the studies have focused on the identification and domain organization of galectin-like transcripts or proteins in diverse tissues and cell types, including hemocytes, and their expression upon environmental or infectious challenge. Lectins from the eastern oyster Crassostrea virginica, however, have been characterized in their molecular, structural and functional aspects and some notable features have become apparent in the galectin repertoire of aquatic mollusks. These including less diversified galectin repertoires and different domain organizations relative to those observed in vertebrates, carbohydrate specificity for blood group oligosaccharides, and up regulation of galectin expression by infectious challenge, a feature that supports their proposed role(s) in innate immune responses. Although galectins from some aquatic mollusks have been shown to recognize microbial pathogens and parasites and promote their phagocytosis, they can also selectively bind to phytoplankton components, suggesting that they also participate in uptake and intracellular digestion of microalgae. In addition, the experimental evidence suggests that the protozoan parasite Perkinsus marinus has co-evolved with the oyster host to be selectively recognized by the oyster hemocyte galectins over algal food or bacterial pathogens, thereby subverting the oyster’s innate immune/feeding recognition mechanisms to gain entry into the host cells. PMID:25982395

Galectin-1 Protein Therapy Prevents Pathology and Improves Muscle Function in the mdx Mouse Model of Duchenne Muscular Dystrophy.

PubMed

Van Ry, Pam M; Wuebbles, Ryan D; Key, Megan; Burkin, Dean J

2015-08-01

Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disease caused by mutations in the dystrophin gene, leading to the loss of a critical component of the sarcolemmal dystrophin glycoprotein complex. Galectin-1 is a small 14 kDa protein normally found in skeletal muscle and has been shown to be a modifier of immune response, muscle repair, and apoptosis. Galectin-1 levels are elevated in the muscle of mouse and dog models of DMD. Together, these findings led us to hypothesize that Galectin-1 may serve as a modifier of disease progression in DMD. To test this hypothesis, recombinant mouse Galectin-1 was produced and used to treat myogenic cells and the mdx mouse model of DMD. Here we show that intramuscular and intraperitoneal injections of Galectin-1 into mdx mice prevented pathology and improved muscle function in skeletal muscle. These improvements were a result of enhanced sarcolemmal stability mediated by elevated utrophin and α7β1 integrin protein levels. Together our results demonstrate for the first time that Galectin-1 may serve as an exciting new protein therapeutic for the treatment of DMD.

Non-synonymous single nucleotide polymorphisms in genes for immunoregulatory galectins: association of galectin-8 (F19Y) occurrence with autoimmune diseases in a Caucasian population.

PubMed

Pál, Zsuzsanna; Antal, Péter; Srivastava, Sanjeev Kumar; Hullám, Gábor; Semsei, Agnes F; Gál, János; Svébis, Mihály; Soós, Györgyi; Szalai, Csaba; André, Sabine; Gordeeva, Elena; Nagy, György; Kaltner, Herbert; Bovin, Nicolai V; Molnár, Mária Judit; Falus, András; Gabius, Hans-Joachim; Buzás, Edit Irén

2012-10-01

Galectins are potent immune regulators, with galectin-8 acting as a pro-apoptotic effector on synovial fluid cells and thymocytes and stimulator on T-cells. To set a proof-of-principle example for risk assessment in autoimmunity, and for a mutation affecting physiological galectin sensor functions, a polymorphism in the coding region of the galectin-8 gene (rs2737713; F19Y) was studied for its association with two autoimmune disorders, i.e. rheumatoid arthritis and myasthenia gravis. A case-control analysis and a related quantitative trait-association study were performed to investigate the association of this polymorphism in patients (myasthenia gravis 149, rheumatoid arthritis 214 and 134 as primary and repetitive cohorts, respectively) and 365 ethnically matched (Caucasian) healthy controls. Distribution was also investigated in patients grouped according to their antibody status and age at disease onset. Comparative testing for lectin activity was carried out in ELISA/ELLA-based binding tests with both wild-type and F19Y mutant galectin-8 from peripheral blood mononuclear cell lysates of healthy individuals with different genotypes as well as with recombinant wild-type and F19Y mutant galectin-8 proteins. A strong association was found for rheumatoid arthritis, and a mild one with myasthenia gravis. Furthermore, the presence of the sequence deviation also correlated with age at disease onset in the case of rheumatoid arthritis. The F19Y substitution did not appear to affect carbohydrate binding in solid-phase assays markedly. This is the first report of an association between a galectin-based polymorphism leading to a mutant protein and autoimmune diseases, with evidence for antagonistic pleiotropy. Copyright © 2012 Elsevier B.V. All rights reserved.

Galectins as self/non-self recognition receptors in innate and adaptive immunity: an unresolved paradox

PubMed Central

Vasta, Gerardo R.; Ahmed, Hafiz; Nita-Lazar, Mihai; Banerjee, Aditi; Pasek, Marta; Shridhar, Surekha; Guha, Prasun; Fernández-Robledo, José A.

2012-01-01

Galectins are characterized by their binding affinity for β-galactosides, a unique binding site sequence motif, and wide taxonomic distribution and structural conservation in vertebrates, invertebrates, protista, and fungi. Since their initial description, galectins were considered to bind endogenous (“self”) glycans and mediate developmental processes and cancer. In the past few years, however, numerous studies have described the diverse effects of galectins on cells involved in both innate and adaptive immune responses, and the mechanistic aspects of their regulatory roles in immune homeostasis. More recently, however, evidence has accumulated to suggest that galectins also bind exogenous (“non-self”) glycans on the surface of potentially pathogenic microbes, parasites, and fungi, suggesting that galectins can function as pattern recognition receptors (PRRs) in innate immunity. Thus, a perplexing paradox arises by the fact that galectins also recognize lactosamine-containing glycans on the host cell surface during developmental processes and regulation of immune responses. According to the currently accepted model for non-self recognition, PRRs recognize pathogens via highly conserved microbial surface molecules of wide distribution such as LPS or peptidoglycan (pathogen-associated molecular patterns; PAMPs), which are absent in the host. Hence, this would not apply to galectins, which apparently bind similar self/non-self molecular patterns on host and microbial cells. This paradox underscores first, an oversimplification in the use of the PRR/PAMP terminology. Second, and most importantly, it reveals significant gaps in our knowledge about the diversity of the host galectin repertoire, and the subcellular targeting, localization, and secretion. Furthermore, our knowledge about the structural and biophysical aspects of their interactions with the host and microbial carbohydrate moieties is fragmentary, and warrants further investigation. PMID:22811679

Galectin signature in normal pregnancy and preeclampsia.

PubMed

Blois, Sandra M; Barrientos, Gabriela

2014-03-01

Members of the galectin family are expressed within the female reproductive tract and have been shown to be involved in multiple biological functions that support the progression of pregnancy. Specific expression patterns of different members of this family have been identified at the maternal decidua and on the placental side. In some cases, mechanisms by which galectins exert their functions have been delineated in adverse pregnancy outcomes. This review summarizes studies on galectins that have been documented to be important for pregnancy maintenance, either supporting the maternal adaptation to pregnancy or the placentation process. In addition, we focus our discussion on the role of galectins in preeclampsia, a specific life-threatening pregnancy disorder. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Aberrant expression and hormonal regulation of Galectin-3 in endometriosis women with infertility.

PubMed

Yang, H; Yin, J; Ficarrotta, K; Hsu, S H; Zhang, W; Cheng, C

2016-07-01

To investigate the role and potential molecular mechanism of Galectin-3 (Gal-3) in the etiology of endometriosis-associated infertility. We detected Gal-3 expression in eutopic endometrium from women with endometriosis-associated infertility and healthy women without endometriosis or infertility. We then evaluated Gal-3 expression in endometrial glandular epithelial cells (EECs) and endometrial stromal cells (ESCs) and investigated its response to hormone stimulation in EECs and ESCs from both groups of women. Results of real-time PCR and western blot analysis showed Gal-3 expression in both proliferative and secretory stages of the menstrual cycle decreased significantly in women with endometriosis-associated infertility compared to healthy women. The changes in expression of Gal-3 were more dramatic in EECs than ESCs. Moreover, estrogen (E2) and progesterone (P4) induced Gal-3 expression in EECs of healthy groups, and P4 was more significant than E2 and combined E2 and P4 (E2P4). However, in the endometriosis group, P4 failed to induce a similar increase in Gal-3 expression. Our results suggest that aberrant expression of Gal-3 might contribute to infertility in patients with endometriosis due to progesterone resistance.

Eosinophils from hematopoietic stem cell recipients suppress allogeneic T cell proliferation.

PubMed

Andersson, Jennie; Cromvik, Julia; Ingelsten, Madeleine; Lingblom, Christine; Andersson, Kerstin; Johansson, Jan-Erik; Wennerås, Christine

2014-12-01

Eosinophilia has been associated with less severe graft-versus-host disease (GVHD), but the underlying mechanism is unknown. We hypothesized that eosinophils diminish allogeneic T cell activation in patients with chronic GVHD. The capacity of eosinophils derived from healthy subjects and hematopoietic stem cell (HSC) transplant recipients, with or without chronic GVHD, to reduce allogeneic T cell proliferation was evaluated using a mixed leukocyte reaction. Eosinophil-mediated inhibition of proliferation was observed for the eosinophils of both healthy subjects and patients who underwent HSC transplantation. Eosinophils from patients with and without chronic GVHD were equally suppressive. Healthy eosinophils required cell-to-cell contact for their suppressive capacity, which was directed against CD4(+) T cells and CD8(+) T cells. Neither eosinophilic cationic protein, eosinophil-derived neurotoxin, indoleamine 2,3-dioxygenase, or increased numbers of regulatory T cells could account for the suppressive effect of healthy eosinophils. Real-time quantitative PCR analysis revealed significantly increased mRNA levels of the immunoregulatory protein galectin-10 in the eosinophils of both chronic GVHD patients and patients without GVHD, as compared with those from healthy subjects. The upregulation of galectin-10 expression in eosinophils from patients suggests a stimulatory effect of HSC transplantation in itself on eosinophilic galectin-10 expression, regardless of chronic GVHD status. To conclude, eosinophils from HSC transplant recipients and healthy subjects have a T cell suppressive capacity. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Doxorubicin attached to HPMA copolymer via amide bond modifies the glycosylation pattern of EL4 cells.

PubMed

Kovar, Lubomir; Etrych, Tomas; Kabesova, Martina; Subr, Vladimir; Vetvicka, David; Hovorka, Ondrej; Strohalm, Jiri; Sklenar, Jan; Chytil, Petr; Ulbrich, Karel; Rihova, Blanka

2010-08-01

To avoid the side effects of the anti-cancer drug doxorubicin (Dox), we conjugated this drug to a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer backbone. Dox was conjugated via an amide bond (Dox-HPMA(AM), PK1) or a hydrazone pH-sensitive bond (Dox-HPMA(HYD)). In contrast to Dox and Dox-HPMA(HYD), Dox-HPMA(AM) accumulates within the cell's intracellular membranes, including those of the Golgi complex and endoplasmic reticulum, both involved in protein glycosylation. Flow cytometry was used to determine lectin binding and cell death, immunoblot to characterize the presence of CD7, CD43, CD44, and CD45, and high-performance anion exchange chromatography with pulsed amperometric detector analysis for characterization of plasma membrane saccharide composition. Incubation of EL4 cells with Dox-HPMA(AM) conjugate, in contrast to Dox or Dox-HPMA(HYD), increased the amounts of membrane surface-associated glycoproteins, as well as saccharide moieties recognized by peanut agglutinin, Erythrina cristagalli, or galectin-1 lectins. Only Dox-HPMA(AM) increased expression of the highly glycosylated membrane glycoprotein CD43, while expression of others (CD7, CD44, and CD45) was unaffected. The binding sites for galectin-1 are present on CD43 molecule. Furthermore, we present that EL4 treated with Dox-HPMA(AM) possesses increased sensitivity to galectin-1-induced apoptosis. In this study, we demonstrate that Dox-HPMA(AM) treatment changes glycosylation of the EL4 T cell lymphoma surface and sensitizes the cells to galectin-1-induced apoptosis.

Analysis of novel cardiovascular biomarkers in patients with peripheral artery disease (PAD).

PubMed

Jirak, Peter; Mirna, Moritz; Wernly, Bernhard; Paar, Vera; Thieme, Marcus; Betge, Stefan; Franz, Marcus; Hoppe, Uta; Lauten, Alexander; Kammler, Jürgen; Schulze, Paul C; Lichtenauer, Michael; Kretzschmar, Daniel

2018-04-12

Peripheral artery disease (PAD) is a common form of manifestation of atherosclerosis. PAD has a considerable impact on morbidity, hospitalisation rates and health- care costs. Biomarkers have been introduced in many cardiovascular disease entities over the last years. However, an analysis on the correlation of biomarker levels and PAD is still lacking. A total of 106 patients were enrolled in this current study, 51 that were diagnosed with PAD and 55 with excluded coronary and peripheral artery disease as controls. During outpatient visits, plasma samples of all patients were obtained and analyzed for sST2 (hemodynamics and inflammation), Galectin-3 (fibrosis and remodeling), GDF-15 (remodeling and inflammation), suPAR (inflammation), and Fetuin-A (vascular calcification) by use of ELISA after informed consent. Compared with controls, patients with PAD showed significantly higher levels of sST2 (5248 vs. 7503 pg/ml, p<0.001), suPAR (2267 vs. 2414 pg/ml, p=0.02), Galectin-3 (2795 vs. 4494 pg/ml, p<0.001), and GDF-15 (549 vs. 767 pg/ml, p<0.001). Fetuin-A showed a trend towards lower levels in patients with PAD (117 vs. 100 ng/ml, p=0.119). Circulating levels of sST2, suPAR, Galectin-3, and GDF-15 were significantly elevated in PAD patients. In contrast, Fetuin-A levels showed a decrease in PAD patients indicating increased vascular calcification. Thus, by incorporating different pathophysiological processes present in PAD, tested novel biomarkers facilitate a more precise diagnosis as well as a more accurate evaluation of disease severity and progression.

The Role of Different Molecular Markers in Papillary Thyroid Cancer Patients with Acromegaly.

PubMed

Keskin, Fatma Ela; Ozkaya, Hande Mefkure; Ferahman, Sina; Haliloglu, Ozlem; Karatas, Adem; Aksoy, Figen; Kadioglu, Pinar

2018-06-11

Prevalence of papillary thyroid cancer (PTC) is increased in patients with acromegaly. We aimed to determine the protein expression of BRAF, RAS, RET, insulin like growth factor 1(IGF1), Galectine 3, CD56 in patients with PTC related acromegaly and to compare the extensity of these expressions with normal PTC patients and benign thyroid nodules. We studied 313 patients with acromegaly followed in Cerrahpasa Medical Faculty, Endocrinology and Metabolism Clinic between 1998 and 2015. On the basis of availability of pathological specimen of thyroid tissues, thyroid samples of 13 patients from 19 with acromegaly related PTC (APTC), 20 normal PTC and 20 patients with multinodulary goiter (MNG) were histopathologically evaluated. Protein expressions were determined via immunohistochemical staining in ex-vivo tumor samples and benign nodules. The incidence of PTC in acromegaly patients were 6% (n=19). Among patients with PTC, APTC and MNG, all the immunohistochemical protein expressions we have studied were higher in papillary thyroid cancer groups (p<0.01, for all). Between PTC group without acromegaly and APTC, galectin 3 and IGF1 expression was significantly higher in acromegalic patients (p<0.01 for all) while RAS was predominantly higher in PTC patients without acromegaly (p<0.01). BRAF expression was not higher in PTC with acromegaly patients compared to PTC patients without acromegaly. Galectine 3 and IGF1 were expressed more intensively in APTC. These positive protein expressions may have more influence on determining malign nodules among acromegaly patients. © Georg Thieme Verlag KG Stuttgart · New York.

Cell Surface Galectin-9 Expressing Th Cells Regulate Th17 and Foxp3+ Treg Development by Galectin-9 Secretion

PubMed Central

Niki, Toshiro; Kadowaki, Takeshi; Ueno, Masaki; Nishi, Nozomu; Yamauchi, Akira; Hattori, Toshio; Masaki, Tsutomu; Hirashima, Mitsuomi

2012-01-01

Galectin-9 (Gal-9), a β-galactoside binding mammalian lectin, regulates immune responses by reducing pro-inflammatory IL-17-producing Th cells (Th17) and increasing anti-inflammatory Foxp3+ regulatory T cells (Treg) in vitro and in vivo. These functions of Gal-9 are thought to be exerted by binding to receptor molecules on the cell surface. However, Gal-9 lacks a signal peptide for secretion and is predominantly located in the cytoplasm, which raises questions regarding how and which cells secrete Gal-9 in vivo. Since Gal-9 expression does not necessarily correlate with its secretion, Gal-9-secreting cells in vivo have been elusive. We report here that CD4 T cells expressing Gal-9 on the cell surface (Gal-9+ Th cells) secrete Gal-9 upon T cell receptor (TCR) stimulation, but other CD4 T cells do not, although they express an equivalent amount of intracellular Gal-9. Gal-9+ Th cells expressed interleukin (IL)-10 and transforming growth factor (TGF)-β but did not express Foxp3. In a co-culture experiment, Gal-9+ Th cells regulated Th17/Treg development in a manner similar to that by exogenous Gal-9, during which the regulation by Gal-9+ Th cells was shown to be sensitive to a Gal-9 antagonist but insensitive to IL-10 and TGF-β blockades. Further elucidation of Gal-9+ Th cells in humans indicates a conserved role of these cells through evolution and implies the possible utility of these cells for diagnosis or treatment of immunological diseases. PMID:23144904

Lactose binding to galectin-1 modulates structural dynamics, increases conformational entropy, and occurs with apparent negative cooperativity.

PubMed

Nesmelova, Irina V; Ermakova, Elena; Daragan, Vladimir A; Pang, Mabel; Menéndez, Margarita; Lagartera, Laura; Solís, Dolores; Baum, Linda G; Mayo, Kevin H

2010-04-16

Galectins are a family of lectins with a conserved carbohydrate recognition domain that interacts with beta-galactosides. By binding cell surface glycoconjugates, galectin-1 (gal-1) is involved in cell adhesion and migration processes and is an important regulator of tumor angiogenesis. Here, we used heteronuclear NMR spectroscopy and molecular modeling to investigate lactose binding to gal-1 and to derive solution NMR structures of gal-1 in the lactose-bound and unbound states. Structure analysis shows that the beta-strands and loops around the lactose binding site, which are more open and dynamic in the unbound state, fold in around the bound lactose molecule, dampening internal motions at that site and increasing motions elsewhere throughout the protein to contribute entropically to the binding free energy. CD data support the view of an overall more open structure in the lactose-bound state. Analysis of heteronuclear single quantum coherence titration binding data indicates that lactose binds the two carbohydrate recognition domains of the gal-1 dimer with negative cooperativity, in that the first lactose molecule binds more strongly (K(1)=21+/-6 x 10(3) M(-1)) than the second (K(2)=4+/-2 x 10(3) M(-1)). Isothermal calorimetry data fit using a sequential binding model present a similar picture, yielding K(1)=20+/-10 x 10(3) M(-1) and K(2)=1.67+/-0.07 x 10(3) M(-1). Molecular dynamics simulations provide insight into structural dynamics of the half-loaded lactose state and, together with NMR data, suggest that lactose binding at one site transmits a signal through the beta-sandwich and loops to the second binding site. Overall, our results provide new insight into gal-1 structure-function relationships and to protein-carbohydrate interactions in general. Copyright (c) 2010. Published by Elsevier Ltd.

Galectin 3 complements BNP in risk stratification in acute heart failure.

PubMed

Fermann, Gregory J; Lindsell, Christopher J; Storrow, Alan B; Hart, Kimberly; Sperling, Matthew; Roll, Susan; Weintraub, Neal L; Miller, Karen F; Maron, David J; Naftilan, Allen J; McPherson, John A; Sawyer, Douglas B; Christenson, Robert; Collins, Sean P

2012-12-01

Galectin 3 (G3) is a mediator of fibrosis and remodeling in heart failure. Patients diagnosed with and treated for Acute Heart Failure Syndromes were prospectively enrolled in the Decision Making in Acute Decompensated Heart Failure multicenter trial. Patients with a higher G3 had a history of renal disease, a lower heart rate and acute kidney injury. They also tended to have a history of HF and 30-day adverse events compared with B-type natriuretic peptide. In Acute Heart Failure Syndromes, G3 levels do not provide prognostic value, but when used complementary to B-type natriuretic peptide, G3 is associated with renal dysfunction and may predict 30-day events.

CHARACTERIZATION OF INFLAMMATORY GENE EXPRESSION AND GALECTIN-3 FUNCTION AFTER SPINAL CORD INJURY IN MICE

PubMed Central

Pajoohesh-Ganji, Ahdeah; Knoblach, Susan M.; Faden, Alan I.; Byrnes, Kimberly R.

2012-01-01

Inflammation has long been implicated in secondary tissue damage after spinal cord injury (SCI). Our previous studies of inflammatory gene expression in rats after SCI revealed two temporally correlated clusters: the first was expressed early after injury and the second was up-regulated later, with peak expression at 1–2 weeks and persistent up-regulation through 6 months. To further address the role of inflammation after SCI, we examined inflammatory genes in a second species, mice, through 28 days after SCI. Using anchor gene clustering analysis, we found similar expression patterns for both the acute and chronic gene clusters previously identified after rat SCI. The acute group returned to normal expression levels by 7 days post-injury. The chronic group, which included C1qB, p22phox and galectin-3, showed peak expression at 7 days and remained up-regulated through 28 days. Immunohistochemistry and western blot analysis showed that the protein expression of these genes was consistent with the mRNA expression. Further exploration of the role of one of these genes, galectin-3, suggests that galectin-3 may contribute to secondary injury. In summary, our findings extend our prior gene profiling data by demonstrating the chronic expression of a cluster of microglial associated inflammatory genes after SCI in mice. Moreover, by demonstrating that inhibition of one such factor improves recovery, the findings suggest that such chronic up-regulation of inflammatory processes may contribute to secondary tissue damage after SCI, and that there may be a broader therapeutic window for neuroprotection than generally accepted. PMID:22884909

Galectin-9 exhibits anti-myeloma activity through JNK and p38 MAP kinase pathways.

PubMed

Kobayashi, T; Kuroda, J; Ashihara, E; Oomizu, S; Terui, Y; Taniyama, A; Adachi, S; Takagi, T; Yamamoto, M; Sasaki, N; Horiike, S; Hatake, K; Yamauchi, A; Hirashima, M; Taniwaki, M

2010-04-01

Galectins constitute a family of lectins that specifically exhibit the affinity for beta-galactosides and modulate various biological events. Galectin-9 is a tandem-repeat type galectin with two carbohydrate recognition domains and has recently been shown to have an anti-proliferative effect on cancer cells. We investigated the effect of recombinant protease-resistant galectin-9 (hGal9) on multiple myeloma (MM). In vitro, hGal9 inhibited the cell proliferation of five myeloma cell lines examined, including a bortezomib-resistant subcell line, with IC(50) between 75.1 and 280.0 nM, and this effect was mediated by the induction of apoptosis with the activation of caspase-8, -9, and -3. hGal9-activated Jun NH(2)-terminal kinase (JNK) and p38 MAPK signaling pathways followed by H2AX phosphorylation. Importantly, the inhibition of either JNK or p38 MAPK partly inhibited the anti-proliferative effect of hGal9, indicating the crucial role of these pathways in the anti-MM effect of hGal9. hGal9 also induced cell death in patient-derived myeloma cells, some with poor-risk factors, such as chromosomal deletion of 13q or translocation t(4;14)(p16;q32). Finally, hGal9 potently inhibited the growth of human myeloma cells xenografted in nude mice. These suggest that hGal9 is a new therapeutic target for MM that may overcome resistance to conventional chemotherapy.

Dietary, nondigestible oligosaccharides and Bifidobacterium breve M-16V suppress allergic inflammation in intestine via targeting dendritic cell maturation.

PubMed

de Kivit, Sander; Kostadinova, Atanaska I; Kerperien, JoAnn; Morgan, Mary E; Muruzabal, Veronica Ayechu; Hofman, Gerard A; Knippels, Leon M J; Kraneveld, Aletta D; Garssen, Johan; Willemsen, Linette E M

2017-07-01

Dietary intervention with short-chain galacto-oligosaccharides (scGOS), long-chain fructo-oligosaccharides (lcFOS) and Bifidobacterium breve M-16V ( Bb ) (GF/ Bb ) suppresses food allergic symptoms in mice, potentially via intestinal epithelial cell (IEC)-derived galectin-9. Furthermore, in vitro studies showed galacto- and fructo-oligosaccharides (GF) to enhance the immunomodulatory capacity of a TLR9 ligand representing bacterial CpG DNA when exposed to IEC. In this study, we investigated whether GF/ Bb modulates dendritic cells (DCs) and subsequent Th2 and regulatory T cell (T reg ) frequency in the small intestinal lamina propria (SI-LP). BALB/c mice were fed GF/ Bb during oral OVA sensitization. DC and T cell phenotype were determined in SI-LP mononuclear cells using flow cytometry. Murine bone marrow-derived DCs (BMDCs) were exposed to recombinant galectin-9 or human monocyte-derived DCs (moDCs) and were cultured in IEC-conditioned medium from GF and TLR9 ligand-exposed HT-29 cells. GF/ Bb reduced allergic symptoms and enhanced serum galectin-9 levels, while suppressing activation, restoring phagocytic capacity, and normalizing CD103 expression of SI-LP DCs of OVA-allergic mice. In vitro, galectin-9 suppressed LPS-induced activation markers and cytokine secretion by BMDCs, and IEC-conditioned medium suppressed moDC activation in a galectin-9-dependent manner. Besides suppression of SI-LP DC activation, dietary GF/ Bb also lowered the frequency of activated Th2 cells, while enhancing T reg in the SI-LP of OVA-allergic mice compared to the control diet. Dietary intervention with GF/ Bb enhances galectin-9 and suppresses allergic symptoms of OVA-allergic mice in association with reduced intestinal DC and Th2 activation and increased T reg frequency in these mice. © Society for Leukocyte Biology.

NMR and MD Investigations of Human Galectin-1/Oligosaccharide Complexes

PubMed Central

Meynier, Christophe; Feracci, Mikael; Espeli, Marion; Chaspoul, Florence; Gallice, Philippe; Schiff, Claudine; Guerlesquin, Françoise; Roche, Philippe

2009-01-01

Abstract The specific recognition of carbohydrates by lectins plays a major role in many cellular processes. Galectin-1 belongs to a family of 15 structurally related β-galactoside binding proteins that are able to control a variety of cellular events, including cell cycle regulation, adhesion, proliferation, and apoptosis. The three-dimensional structure of galectin-1 has been solved by x-ray crystallography in the free form and in complex with various carbohydrate ligands. In this work, we used a combination of two-dimensional NMR titration experiments and molecular-dynamics simulations with explicit solvent to study the mode of interaction between human galectin-1 and five galactose-containing ligands. Isothermal titration calorimetry measurements were performed to determine their affinities for galectin-1. The contribution of the different hexopyranose units in the protein-carbohydrate interaction was given particular consideration. Although the galactose moiety of each oligosaccharide is necessary for binding, it is not sufficient by itself. The nature of both the reducing sugar in the disaccharide and the interglycosidic linkage play essential roles in the binding to human galectin-1. PMID:20006954

Imaging galectin-3 dependent endocytosis with lattice light-sheet microscopy

NASA Astrophysics Data System (ADS)

Baek, Jongho; Lou, Jieqiong; Coelho, Simao; Lim, Yean Jin; Seidlitz, Silvia; Nicovich, Philip R.; Wunder, Christian; Johannes, Ludger; Gaus, Katharina

2017-04-01

Lattice light-sheet (LLS) microscopy provides ultrathin light sheets of a two-dimensional optical lattice that allows us imaging three-dimensional (3D) objects for hundreds of time points at sub-second intervals and at or below the diffraction limit. Galectin-3 (Gal3), a carbohydrate-binding protein, triggers glycosphingolipid (GSL)-dependent biogenesis of morphologically distinct endocytic vesicles that are cargo specific and clathrin independent. In this study, we apply LLS microscopy to study the dynamics of Gal3 dependent endocytosis in live T cells. This will allow us to observe Gal3-mediated endocytosis at high temporal and excellent 3D spatial resolution, which may shed light on our understanding of the mechanism and physiological function of Gal3-induced endocytosis.

Characterisation and functional comparison of single-CRD and multidomain containing galectins CgGal-2 and CgGal-3 from oyster Crassostrea gigas.

PubMed

Huang, Mengmeng; Zhou, Tao; Wu, Yuehong; Fei, Hui; Wang, Gaoyang; Li, Zhi; Lei, Yutong; Liu, Qian; Sun, Cong; Lv, Zhengbing; Xu, Xue-Wei

2018-04-18

Galectins are β-galactoside binding lectins that play crucial roles in innate immunity in vertebrates and invertebrates through their conserved carbohydrate-recognition domains (CRDs). In the present study, single- and four-CRD-containing galectins were identified in oyster Crassostrea gigas (designated CgGal-2 and CgGal-3). The open reading frames (ORFs) of CgGal-2 and CgGal-3 encode polypeptides of 200 and 555 amino acids, respectively. All CRDs of CgGal-3 include two consensus motifs essential for ligand-binding, and a novel motif is present in CgGal-2. Pathogen-associated molecular pattern (PAMP) profiles were determined for recombinant rCgGal-2 and rCgGal-3, and rCgGal-2 displayed low binding affinity for PAMPs, while rCgGal-3 bound various PAMPs including glucan, lipopolysaccharide (LPS), and peptidoglycan (PGN) with relatively high affinity. Furthermore, rCgGal-2 and rCgGal-3 exhibited different microbe binding profiles; rCgGal-2 bound to Gram-negative bacteria (Escherichia coli and Vibrio vulnificus) and fungi (Saccharomyces cerevisiae and Pichia pastoris), while rCgGal-3 bound to these microbes but also to Gram-positive bacteria (Micrococcus luteus). In addition, rCgGal-3 possessed microbial agglutinating activity and coagulation activity against fungi and erythrocytes, respectively, but rCgGal-2 lacked any agglutinating activity. Carbohydrate binding specificity analysis showed that rCgGal-3 specifically bound D-galactose. Furthermore, rCgGal-2 and rCgGal-3 functioned as opsonin participating in the clearance against invaders in C. gigas. Thus, CgGal-2 with one CRD and CgGal-3 with four CRDs are new members of the galectin family involved in immune responses against bacterial infection. Differences in the organisation and amino acid sequences of CRDs may affect their specificity and affinity for nonself substances. Copyright © 2018 Elsevier Ltd. All rights reserved.

Expression profiles and clinical value of plasma exosomal Tim-3 and Galectin-9 in non-small cell lung cancer.

PubMed

Gao, Jianwei; Qiu, Xiangyu; Li, Xinying; Fan, Hang; Zhang, Fang; Lv, Tangfeng; Song, Yong

2018-04-06

Exosomes are membrane-bound, virus-sized vesicles present in circulating blood. Tumor cells are avid producers of exosomes, which are thought to mimic molecular features of parent tumor cells. T-cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) is a the next-generation immune checkpoint that can be activated by its ligand Galectin-9 to negatively regulate the anti-tumor immune response. However, the characteristics of plasma exosomal Tim-3 and Galectin-9 (Exo-T/G) in cancer remained unknown. This study was conducted to investigate the expression patterns and clinical value of plasma exosomal total protein (Exo-pro) and Exo-T/G in non-small cell lung cancer (NSCLC). Plasma was collected from 103 NSCLC patients including 60 early stages and 43 advanced stages disease samples as well as 56 healthy subjects. Exosomes were isolated from plasma by commercial exosome precipitation solution and identified by western blotting of CD63 and transmission electron microscopy. Exo-pro concentration was measured by the BCA assay. Enzyme-linked immunosorbent assay was used to quantify Exo-T/G. Additionally, 34 NSCLC samples were applied to directly detect plasma TIM-3 (Plas-T) and Galectin-9 (Plas-G). Our results showed that Exo-pro, Exo-T, and Exo-G were significantly increased in NSCLC plasma compared to that in the healthy samples. High levels of Exo-T and Exo-G were all positively correlated with several malignant parameters, including larger tumor size, advanced stages, and more distant metastasis. High levels of Exo-pro and Exo-T were also correlated with more lymph node metastasis. Additionally, plasma from lung squamous cell carcinoma showed higher Exo-T and Exo-G compared with that from lung adenocarcinoma. ALK-positive patients showed to have decreased Exo-T and Exo-G levels. Pearson's correlation analysis revealed a significant correlation between Exo-pro and Exo-T/G, Exo-T and Exo-G, Exo-T and Plas-T, Exo-G and Plas-G, and Plas-T and Plas-G. Together, our data revealed that Exo-pro, especially Exo-T and Exo-G could be potential biomarkers for NSCLC. Further studies focusing on pure tumor-derived exosomes isolated from plasma were needed. Copyright © 2018 Elsevier Inc. All rights reserved.

An Impermeant Ganetespib Analog Inhibits Extracellular Hsp90-Mediated Cancer Cell Migration that Involves Lysyl Oxidase 2-like Protein.

PubMed

McCready, Jessica; Wong, Daniel S; Burlison, Joseph A; Ying, Weiwen; Jay, Daniel G

2014-04-30

Extracellular Hsp90 (eHsp90) activates a number of client proteins outside of cancer cells required for migration and invasion. Therefore, eHsp90 may serve as a novel target for anti-metastatic drugs as its inhibition using impermeant Hsp90 inhibitors would not affect the numerous vital intracellular Hsp90 functions in normal cells. While some eHsp90 clients are known, it is important to establish other proteins that act outside the cell to validate eHsp90 as a drug target to limit cancer spread. Using mass spectrometry we identified two precursor proteins Galectin 3 binding protein (G3BP) and Lysyl oxidase 2-like protein (LOXL2) that associate with eHsp90 in MDA-MB231 breast cancer cell conditioned media and confirmed that LOXL2 binds to eHsp90 in immunoprecipitates. We introduce a novel impermeant Hsp90 inhibitor STA-12-7191 derived from ganetespib and show that it is markedly less toxic to cells and can inhibit cancer cell migration in a dose dependent manner. We used STA-12-7191 to test if LOXL2 and G3BP are potential eHsp90 clients. We showed that while LOXL2 can increase wound healing and compensate for STA-12-7191-mediated inhibition of wound closure, addition of G3BP had no affect on this assay. These findings support of role for LOXL2 in eHsp90 stimulated cancer cell migration and provide preliminary evidence for the use of STA-12-7191 to inhibit eHsp90 to limit cancer invasion.

An Impermeant Ganetespib Analog Inhibits Extracellular Hsp90-Mediated Cancer Cell Migration that Involves Lysyl Oxidase 2-like Protein

PubMed Central

McCready, Jessica; Wong, Daniel S.; Burlison, Joseph A.; Ying, Weiwen; Jay, Daniel G.

2014-01-01

Extracellular Hsp90 (eHsp90) activates a number of client proteins outside of cancer cells required for migration and invasion. Therefore, eHsp90 may serve as a novel target for anti-metastatic drugs as its inhibition using impermeant Hsp90 inhibitors would not affect the numerous vital intracellular Hsp90 functions in normal cells. While some eHsp90 clients are known, it is important to establish other proteins that act outside the cell to validate eHsp90 as a drug target to limit cancer spread. Using mass spectrometry we identified two precursor proteins Galectin 3 binding protein (G3BP) and Lysyl oxidase 2-like protein (LOXL2) that associate with eHsp90 in MDA-MB231 breast cancer cell conditioned media and confirmed that LOXL2 binds to eHsp90 in immunoprecipitates. We introduce a novel impermeant Hsp90 inhibitor STA-12-7191 derived from ganetespib and show that it is markedly less toxic to cells and can inhibit cancer cell migration in a dose dependent manner. We used STA-12-7191 to test if LOXL2 and G3BP are potential eHsp90 clients. We showed that while LOXL2 can increase wound healing and compensate for STA-12-7191-mediated inhibition of wound closure, addition of G3BP had no affect on this assay. These findings support of role for LOXL2 in eHsp90 stimulated cancer cell migration and provide preliminary evidence for the use of STA-12-7191 to inhibit eHsp90 to limit cancer invasion. PMID:24785146

The zebrafish galectins Drgal1-L2 and Drgal3-L1 bind in vitro to the infectious hematopoietic necrosis virus (IHNV) glycoprotein and reduce viral adhesion to fish epithelial cells*

PubMed Central

Feng, Chiguang; González-Montalbán, Núria; Ravindran, Chinnarajan; Jackson, Shawn; de las Heras-Sánchez, Ana; Giomarelli, Barbara; Ahmed, Hafiz; Haslam, Stuart M.; Wu, Gang; Dell, Anne; Ammayappan, Arun; Vakharia, Vikram N.; Vasta, Gerardo R.

2015-01-01

The infectious hematopoietic necrosis virus (IHNV; Rhabdoviridae, Novirhabdovirus) infects teleost fish, such as salmon and trout, and is responsible for significant losses in the aquaculture industry and in wild fish populations. Although IHNV enters the host through the skin at the base of the fins, the viral adhesion and entry mechanisms are not fully understood. In recent years, evidence has accumulated in support of the key roles played by protein-carbohydrate interactions between host lectins secreted to the extracellular space and virion envelope glycoproteins in modulating viral adhesion and infectivity. In this study, we assessed in vitro the potential role(s) of zebrafish (Danio rerio) proto type galectin-1 (Drgal1-L2) and a chimera galectin-3 (Drgal3-L1) in IHNV adhesion to epithelial cells. Our results suggest that the extracellular Drgal1-L2 and Drgal3-L1 interact directly and in a carbohydrate-dependent manner with the IHNV glycosylated envelope and glycans on the epithelial cell surface, significantly reducing viral adhesion. PMID:26429411

Dynamic pre-BCR homodimers fine-tune autonomous survival signals in B cell precursor acute lymphoblastic leukemia

PubMed Central

Erasmus, M. Frank; Matlawska-Wasowska, Ksenia; Kinjyo, Ichiko; Mahajan, Avanika; Winter, Stuart S.; Xu, Li; Horowitz, Michael; Lidke, Diane S.; Wilson, Bridget S.

2017-01-01

The pre-B cell receptor (pre-BCR) is an immature form of the BCR critical for early B lymphocyte development. It is composed of the membrane-bound immunoglobulin (Ig) heavy chain, surrogate light chain components, and the signaling subunits Igα and Igβ. We developed monovalent Quantum Dot (QD)-labeled probes specific for Igβ to study the behavior of pre-BCRs engaged in autonomous, ligand-independent signaling in live B cells. Single-particle tracking revealed that QD-labeled pre-BCRs engaged in transient, but frequent, homotypic interactions. Receptor motion was correlated at short separation distances, consistent with the formation of dimers and higher-order oligomers. Repeated encounters between diffusing pre-BCRs appeared to reflect transient co-confinement in plasma membrane domains. In human B cell precursor acute lymphoblastic leukemia (BCP-ALL) cells, we showed that frequent, short-lived, homotypic pre-BCR interactions stimulated survival signals, including expression of BCL6, which encodes a transcriptional repressor. These survival signals were blocked by inhibitory monovalent antigen-binding antibody fragments (Fabs) specific for the surrogate light chain components of the pre-BCR or by inhibitors of the tyrosine kinases Lyn and Syk. For comparison, we evaluated pre-BCR aggregation mediated by dimeric galectin-1, which has binding sites for carbohydrate and for the λ5 component of the surrogate light chain. Galectin-1 binding resulted in the formation of large, highly immobile pre-BCR aggregates, which was partially relieved by the addition of lactose to prevent the crosslinking of galectin-BCR complexes to other glycosylated membrane components. Analysis of the pre-BCR and its signaling partners suggested that they could be potential targets for combination therapy in BCP-ALL. PMID:27899526

Galectin 3 complements BNP in risk stratification in acute heart failure

PubMed Central

Fermann, Gregory J.; Lindsell, Christopher J.; Storrow, Alan B.; Hart, Kimberly; Sperling, Matthew; Roll, Susan; Weintraub, Neal L.; Miller, Karen F.; Maron, David J.; Naftilan, Allen J.; Mcpherson, John A.; Sawyer, Douglas B.; Christenson, Robert; Collins, Sean P.

2013-01-01

Background Galectin 3 (G3) is a mediator of fibrosis and remodeling in heart failure. Methods Patients diagnosed with and treated for Acute Heart Failure Syndromes were prospectively enrolled in the Decision Making in Acute Decompensated Heart Failure multicenter trial. Results Patients with a higher G3 had a history of renal disease, a lower heart rate and acute kidney injury. They also tended to have a history of HF and 30-day adverse events compared with B-type natriuretic peptide. Conclusion In Acute Heart Failure Syndromes, G3 levels do not provide prognostic value, but when used complementary to B-type natriuretic peptide, G3 is associated with renal dysfunction and may predict 30-day events. PMID:22998064

Gene expression of galectin-9/ecalectin, a potent eosinophil chemoattractant, and/or the insertional isoform in human colorectal carcinoma cell lines and detection of frame-shift mutations for protein sequence truncations in the second functional lectin domain.

PubMed

Lahm, H; Hoeflich, A; Andre, S; Sordat, B; Kaltner, H; Wolf, E; Gabius, H J

2000-09-01

The family of Ca2+-independent galactoside-binding lectins with the beta-strand topology of the jelly-roll, referred to as galectins, is known to mediate and modulate a variety of cellular activities. Their functional versatility explains the current interest in monitoring their expression in cancer research, so far primarily focused on galectin-1 and -3. Tandem-repeat-type galectin-9 and its (most probably) allelic variant ecalectin, a potent eosinophil chemoattractant, are known to be human leukocyte products. We show by RT-PCR with primers specific for both that their mRNA is expressed in 17 of 21 human colorectal cancer lines. As also indicated by restriction analysis, in addition to the expected transcript of 571 bp an otherwise identical isoform coding for a 32-amino acid extension of the link peptide was detected. Positive cell lines differentially expressed either one (7 lines) or both transcripts (10 lines). Sequence analysis of RT-PCR products, performed in four cases, allowed to assign the standard transcript to ecalectin in the case of SW480 cells and detected two point mutations in the insert of the link peptide-coding sequence in WiDr and Colo205. Furthermore, this analysis identified the insertion of a single nucleotide into the coding sequence generating a frame-shift mutation, an event which has so far not been reported for any galectin. This alteration encountered in both transcripts of the WiDr line and the isoform transcript of Colo205 cells will most likely truncate the protein part within the second (C-terminal) carbohydrate recognition domain. Our results thus reveal the presence of mRNA for a galectin-9-isoform or a potent eosinophil chemoattractant (ecalectin) or a truncated version thereof with preserved N-terminal carbohydrate recognition domain in established human colon cancer cell lines.

Galectins in the Pathogenesis of Rheumatoid Arthritis

PubMed Central

Li, Song; Yu, Yangsheng; Koehn, Christopher D; Zhang, Zhixin; Su, Kaihong

2013-01-01

Rheumatoid arthritis (RA) is a complex and common systemic autoimmune disease characterized by synovial inflammation and hyperplasia. Multiple proteins, cells, and pathways have been identified to contribute to the pathogenesis of RA. Galectins are a group of lectins that bind to β-galactoside carbohydrates on the cell surface and in the extracellular matrix. They are expressed in a wide variety of tissues and organs with the highest expression in the immune system. Galectins are potent immune regulators and modulate a range of pathological processes, such as inflammation, autoimmunity, and cancer. Accumulated evidence shows that several family members of galectins play positive or negative roles in the disease development of RA, through their effects on T and B lymphocytes, myeloid lineage cells, and fibroblast-like synoviocytes. In this review, we will summarize the function of different galectins in immune modulation and their distinct roles in RA pathogenesis. PMID:24416634

Inhibition of galectin-3 ameliorates the consequences of cardiac lipotoxicity in a rat model of diet-induced obesity.

PubMed

Marín-Royo, Gema; Gallardo, Isabel; Martínez-Martínez, Ernesto; Gutiérrez, Beatriz; Jurado-López, Raquel; López-Andrés, Natalia; Gutiérrez-Tenorio, Josué; Rial, Eduardo; Bartolomé, Marı A Visitación; Nieto, María Luisa; Cachofeiro, Victoria

2018-02-05

Obesity is accompanied by metabolic alterations characterized by insulin resistance and cardiac lipotoxicity. Galectin-3 (Gal-3) induces cardiac inflammation and fibrosis in the context of obesity; however, its role in the metabolic consequences of obesity is not totally established. We have investigated the potential role of Gal-3 in the cardiac metabolic disturbances associated with obesity. In addition, we have explored whether this participation is, at least partially, acting on mitochondrial damage. Gal-3 inhibition in rats that were fed a high-fat diet (HFD) for 6 weeks with modified citrus pectin (MCP; 100 mg/kg/day) attenuated the increase in cardiac levels of total triglyceride (TG). MCP treatment also prevented the increase in cardiac protein levels of carnitine palmitoyl transferase IA, mitofusin 1, and mitochondrial complexes I and II, reactive oxygen species accumulation and decrease in those of complex V but did not affect the reduction in 18 F-fluorodeoxyglucose uptake observed in HFD rats. The exposure of cardiac myoblasts (H9c2) to palmitic acid increased the rate of respiration, mainly due to an increase in the proton leak, glycolysis, oxidative stress, β-oxidation and reduced mitochondrial membrane potential. Inhibition of Gal-3 activity was unable to affect these changes. Our findings indicate that Gal-3 inhibition attenuates some of the consequences of cardiac lipotoxicity induced by a HFD since it reduced TG and lysophosphatidyl choline (LPC) levels. These reductions were accompanied by amelioration of the mitochondrial damage observed in HFD rats, although no improvement was observed regarding insulin resistance. These findings increase the interest for Gal-3 as a potential new target for therapeutic intervention to prevent obesity-associated cardiac lipotoxicity and subsequent mitochondrial dysfunction . © 2018. Published by The Company of Biologists Ltd.

Inhibition of galectin-3 ameliorates the consequences of cardiac lipotoxicity in a rat model of diet-induced obesity

PubMed Central

Marín-Royo, Gema; Gallardo, Isabel; Martínez-Martínez, Ernesto; Gutiérrez, Beatriz; Jurado-López, Raquel; López-Andrés, Natalia; Gutiérrez-Tenorio, Josué; Rial, Eduardo; Bartolomé, María Visitación; Nieto, María Luisa

2018-01-01

ABSTRACT Obesity is accompanied by metabolic alterations characterized by insulin resistance and cardiac lipotoxicity. Galectin-3 (Gal-3) induces cardiac inflammation and fibrosis in the context of obesity; however, its role in the metabolic consequences of obesity is not totally established. We have investigated the potential role of Gal-3 in the cardiac metabolic disturbances associated with obesity. In addition, we have explored whether this participation is, at least partially, acting on mitochondrial damage. Gal-3 inhibition in rats that were fed a high-fat diet (HFD) for 6 weeks with modified citrus pectin (MCP; 100 mg/kg/day) attenuated the increase in cardiac levels of total triglyceride (TG). MCP treatment also prevented the increase in cardiac protein levels of carnitine palmitoyl transferase IA, mitofusin 1, and mitochondrial complexes I and II, reactive oxygen species accumulation and decrease in those of complex V but did not affect the reduction in 18F-fluorodeoxyglucose uptake observed in HFD rats. The exposure of cardiac myoblasts (H9c2) to palmitic acid increased the rate of respiration, mainly due to an increase in the proton leak, glycolysis, oxidative stress, β-oxidation and reduced mitochondrial membrane potential. Inhibition of Gal-3 activity was unable to affect these changes. Our findings indicate that Gal-3 inhibition attenuates some of the consequences of cardiac lipotoxicity induced by a HFD since it reduced TG and lysophosphatidyl choline (LPC) levels. These reductions were accompanied by amelioration of the mitochondrial damage observed in HFD rats, although no improvement was observed regarding insulin resistance. These findings increase the interest for Gal-3 as a potential new target for therapeutic intervention to prevent obesity-associated cardiac lipotoxicity and subsequent mitochondrial dysfunction. PMID:29361517

Galectin-1-asialofetuin interaction is inhibited by peptides containing the tyr-xxx-tyr motif acting on the glycoprotein.

PubMed

Wéber, Edit; Hetényi, Anasztázia; Váczi, Balázs; Szolnoki, Eva; Fajka-Boja, Roberta; Tubak, Vilmos; Monostori, Eva; Martinek, Tamás A

2010-01-25

Galectin-1 (Gal-1), a ubiquitous beta-galactoside-binding protein expressed by various normal and pathological tissues, has been implicated in cancer and autoimmune/inflammatory diseases in consequence of its regulatory role in adhesion, cell viability, proliferation, and angiogenesis. The functions of Gal-1 depend on its affinity for beta-galactoside-containing glycoconjugates; accordingly, the inhibition of sugar binding blocks its functions, hence promising potential therapeutic tools. The Tyr-Xxx-Tyr peptide motifs have been reported to be glycomimetic sequences, mainly on the basis of their inhibitory effect on the Gal-1-asialofetuin (ASF) interaction. However, the results regarding the efficacy of the Tyr-Xxx-Tyr motif as a glycomimetic inhibitor are still controversial. The present STD and trNOE NMR experiments reveal that the Tyr-Xxx-Tyr peptides studied do not bind to Gal-1, whereas their binding to ASF is clearly detected. (15)N,(1)H HSQC titrations with (15)N-labeled Gal-1 confirm the absence of any peptide-Gal-1 interaction. These data indicate that the Tyr-Xxx-Tyr peptides tested in this work are not glycomimetics as they interact with ASF via an unrevealed molecular linkage.

Expanding the universe of cytokines and pattern recognition receptors: galectins and glycans in innate immunity.

PubMed

Cerliani, Juan P; Stowell, Sean R; Mascanfroni, Iván D; Arthur, Connie M; Cummings, Richard D; Rabinovich, Gabriel A

2011-02-01

Effective immunity relies on the recognition of pathogens and tumors by innate immune cells through diverse pattern recognition receptors (PRRs) that lead to initiation of signaling processes and secretion of pro- and anti-inflammatory cytokines. Galectins, a family of endogenous lectins widely expressed in infected and neoplastic tissues have emerged as part of the portfolio of soluble mediators and pattern recognition receptors responsible for eliciting and controlling innate immunity. These highly conserved glycan-binding proteins can control immune cell processes through binding to specific glycan structures on pathogens and tumors or by acting intracellularly via modulation of selective signaling pathways. Recent findings demonstrate that various galectin family members influence the fate and physiology of different innate immune cells including polymorphonuclear neutrophils, mast cells, macrophages, and dendritic cells. Moreover, several pathogens may actually utilize galectins as a mechanism of host invasion. In this review, we aim to highlight and integrate recent discoveries that have led to our current understanding of the role of galectins in host-pathogen interactions and innate immunity. Challenges for the future will embrace the rational manipulation of galectin-glycan interactions to instruct and shape innate immunity during microbial infections, inflammation, and cancer.

Structure of a tetrameric galectin from Cinachyrella sp. (ball sponge)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Freymann, Douglas M., E-mail: freymann@northwestern.edu; Nakamura, Yuka; Focia, Pamela J.

2012-09-01

The structure of a tetrameric sponge galectin suggests a basis for glutamate receptor potentiation. The galectins are a family of proteins that bind with highest affinity to N-acetyllactosamine disaccharides, which are common constituents of asparagine-linked complex glycans. They play important and diverse physiological roles, particularly in the immune system, and are thought to be critical metastatic agents for many types of cancer cells, including gliomas. A recent bioactivity-based screen of marine sponge (Cinachyrella sp.) extract identified an ancestral member of the galectin family based on its unexpected ability to positively modulate mammalian ionotropic glutamate receptor function. To gain insight intomore » the mechanistic basis of this activity, the 2.1 Å resolution X-ray structure of one member of the family, galectin CchG-1, is reported. While the protomer exhibited structural similarity to mammalian prototype galectin, CchG-1 adopts a novel tetrameric arrangement in which a rigid toroidal-shaped ‘donut’ is stabilized in part by the packing of pairs of vicinal disulfide bonds. Twofold symmetry between binding-site pairs provides a basis for a model for interaction with ionotropic glutamate receptors.« less

Galectin-3 Reflects the Echocardiographic Grades of Left Ventricular Diastolic Dysfunction.

PubMed

Ansari, Uzair; Behnes, Michael; Hoffmann, Julia; Natale, Michele; Fastner, Christian; El-Battrawy, Ibrahim; Rusnak, Jonas; Kim, Seung Hyun; Lang, Siegfried; Hoffmann, Ursula; Bertsch, Thomas; Borggrefe, Martin; Akin, Ibrahim

2018-07-01

The level of Galectin-3 (Gal-3) protein purportedly reflects an ongoing cardiac fibrotic process and has been associated with ventricular remodeling, which is instrumental in the development of heart failure with preserved ejection fraction (HFpEF) syndrome. The aim of this study was to investigate the potential use of Gal-3 in improved characterization of the grades of diastolic dysfunction as defined by echocardiography. Seventy HFpEF patients undergoing routine echocardiography were prospectively enrolled in the present monocentric study. Blood samples for measurements of Gal-3 and amino-terminal pro-brain natriuretic peptide (NT-proBNP) were collected within 24 hours pre- or post-echocardiographic examination. The classification of patients into subgroups based on diastolic dysfunction grade permitted detailed statistical analyses of the derived data. The Gal-3 serum levels of all patients corresponded to echocardiographic indices, suggesting HFpEF (E/A, P=0.03 and E/E', P=0.02). Gal-3 was also associated with progressive diastolic dysfunction, and increased levels corresponded to the course of disease (P=0.012). Detailed analyses of ROC curves suggested that Gal-3 levels could discriminate patients with grade III diastolic dysfunction (area under the curve [AUC]=0.770, P=0.005). Gal-3 demonstrates remarkable effectiveness in the diagnosis of patients suffering from severe grade diastolic dysfunction. Increasing levels of Gal-3 possibly reflect the progressive course of HFpEF, as classified by the echocardiographic grades of diastolic dysfunction. © The Korean Society for Laboratory Medicine.

Quantitative Expression of C-Type Lectin Receptors in Humans and Mice

PubMed Central

Lech, Maciej; Susanti, Heni Eka; Römmele, Christoph; Gröbmayr, Regina; Günthner, Roman; Anders, Hans-Joachim

2012-01-01

C-type lectin receptors and their adaptor molecules are involved in the recognition of glycosylated self-antigens and pathogens. However, little is known about the species- and organ-specific expression profiles of these molecules. We therefore determined the mRNA expression levels of Dectin-1, MR1, MR2, DC-SIGN, Syk, Card-9, Bcl-10, Malt-1, Src, Dec-205, Galectin-1, Tim-3, Trem-1, and DAP-12 in 11 solid organs of human and mice. Mouse organs revealed lower mRNA levels of most molecules compared to spleen. However, Dec-205 and Galectin-1 in thymus, Src in brain, MR2, Card-9, Bcl-10, Src, and Dec-205 in small intestine, MR2, Bcl-10, Src, Galectin-1 in kidney, and Src and Galectin-1 in muscle were at least 2-fold higher expressed compared to spleen. Human lung, liver and heart expressed higher mRNA levels of most genes compared to spleen. Dectin-1, MR1, Syk and Trem-1 mRNA were strongly up-regulated upon ischemia-reperfusion injury in murine kidney. Tim3, DAP-12, Card-9, DC-SIGN and MR2 were further up-regulated during renal fibrosis. Murine kidney showed higher DAP-12, Syk, Card-9 and Dectin-1 mRNA expression during the progression of lupus nephritis. Thus, the organ-, and species-specific expression of C-type lectin receptors is different between mice and humans which must be considered in the interpretation of related studies. PMID:22949850

Bivalent O-glycoside mimetics with S/disulfide/Se substitutions and aromatic core: Synthesis, molecular modeling and inhibitory activity on biomedically relevant lectins in assays of increasing physiological relevance.

PubMed

Kaltner, Herbert; Szabó, Tamás; Fehér, Krisztina; André, Sabine; Balla, Sára; Manning, Joachim C; Szilágyi, László; Gabius, Hans-Joachim

2017-06-15

The emerging significance of recognition of cellular glycans by lectins for diverse aspects of pathophysiology is a strong incentive for considering development of bioactive and non-hydrolyzable glycoside derivatives, for example by introducing S/Se atoms and the disulfide group instead of oxygen into the glycosidic linkage. We report the synthesis of 12 bivalent thio-, disulfido- and selenoglycosides attached to benzene/naphthalene cores. They present galactose, for blocking a plant toxin, or lactose, the canonical ligand of adhesion/growth-regulatory galectins. Modeling reveals unrestrained flexibility and inter-headgroup distances too small to bridge two sites in the same lectin. Inhibitory activity was first detected by solid-phase assays using a surface-presented glycoprotein, with relative activity enhancements per sugar unit relative to free cognate sugar up to nearly 10fold. Inhibitory activity was also seen on lectin binding to surfaces of human carcinoma cells. In order to proceed to characterize this capacity in the tissue context monitoring of lectin binding in the presence of inhibitors was extended to sections of three types of murine organs as models. This procedure proved to be well-suited to determine relative activity levels of the glycocompounds to block binding of the toxin and different human galectins to natural glycoconjugates at different sites in sections. The results on most effective inhibition by two naphthalene-based disulfides and a selenide raise the perspective for broad applicability of the histochemical assay in testing glycoclusters that target biomedically relevant lectins. Copyright © 2017 Elsevier Ltd. All rights reserved.

When galectins recognize glycans: from biochemistry to physiology and back again.

PubMed

Di Lella, Santiago; Sundblad, Victoria; Cerliani, Juan P; Guardia, Carlos M; Estrin, Dario A; Vasta, Gerardo R; Rabinovich, Gabriel A

2011-09-20

In the past decade, increasing efforts have been devoted to the study of galectins, a family of evolutionarily conserved glycan-binding proteins with multifunctional properties. Galectins function, either intracellularly or extracellularly, as key biological mediators capable of monitoring changes occurring on the cell surface during fundamental biological processes such as cellular communication, inflammation, development, and differentiation. Their highly conserved structures, exquisite carbohydrate specificity, and ability to modulate a broad spectrum of biological processes have captivated a wide range of scientists from a wide spectrum of disciplines, including biochemistry, biophysics, cell biology, and physiology. However, in spite of enormous efforts to dissect the functions and properties of these glycan-binding proteins, limited information about how structural and biochemical aspects of these proteins can influence biological functions is available. In this review, we aim to integrate structural, biochemical, and functional aspects of this bewildering and ancient family of glycan-binding proteins and discuss their implications in physiologic and pathologic settings. © 2011 American Chemical Society

Small leucine-rich repeat proteoglycans associated with mature insoluble elastin serve as binding sites for galectins.

PubMed

Itoh, Aiko; Nonaka, Yasuhiro; Ogawa, Takashi; Nakamura, Takanori; Nishi, Nozomu

2017-11-01

We previously reported that galectin-9 (Gal-9), an immunomodulatory animal lectin, could bind to insoluble collagen preparations and exerted direct cytocidal effects on immune cells. In the present study, we found that mature insoluble elastin is capable of binding Gal-9 and other members of the human galectin family. Lectin blot analysis of a series of commercial water-soluble elastin preparations, PES-(A) ~ PES-(E), revealed that only PES-(E) contained substances recognized by Gal-9. Gal-9-interacting substances in PES-(E) were affinity-purified, digested with trypsin and then analyzed by reversed-phase HPLC. Peptide fragments derived from five members of the small leucine-rich repeat proteoglycan family, versican, lumican, osteoglycin/mimecan, prolargin, and fibromodulin, were identified by N-terminal amino acid sequence analysis. The results indicate that Gal-9 and possibly other galectins recognize glycans attached to small leucine-rich repeat proteoglycans associated with insoluble elastin and also indicate the possibility that mature insoluble elastin serves as an extracellular reservoir for galectins.

A study of Galactin-3 on fine needle aspiration as a diagnostic marker differentiating benign from malignant thyroid neoplasm

PubMed Central

Muzafar, Alliya; Bukhari, Mulazim Hussain; Qureshi, Ihtesham uddin

2017-01-01

Background & Objective: Thyroid nodules are very common in our setup and their diagnosis on fine needle aspiration is not easy and is a taxing affair. It is a challenge to differentiate between follicular adenoma and follicular carcinoma without histology. Our objective was to investigate the role of Galectin-3 in fine needle aspirates of thyroid nodules as a prospective diagnostic marker and consequently its ability to differentiate benign from malignant neoplasms. Methods: The research was conducted at the department of Pathology, King Edward Medical University, in association with other teaching institutions of Lahore from June 2012 to July 2014.. Sixty cases of solitary thyroid nodules were included in the study. Haematoxylin and eosin staining of the fixed smears and Galectin-3 immunohistochemical staining of the sections prepared from the cell block was performed. Results: There were 60 patients in our study with a mean age of 33.35 years. The Bethesda system for reporting thyroid cytopathology was used to classify the smears and only categories IV, V and VI were included. On histological examination of the resected nodules there were 38.3% (23/60) cases of follicular adenoma, 46.6% (28/60) were of papillary carcinoma and follicular carcinoma made up to 15% (9/60) of all cases. Galectin-3 was negative in 100% (23/23) cases of follicular adenomas. Out of 37 malignant cases 65% lesions showed positivity, while 35% showed negativity for this immunomarker. Considering the malignant lesions, 75% cases of papillary carcinomas showed a positive reaction while only 33% of follicular carcinomas were positive for the immunomarker. This showed that the positive expression was more common in papillary as compared to follicular carcinomas. Conclusion: Galectin-3immunomarker is considerably expressed in malignant tumors, but it is not expressed in benign follicular lesions. PMID:28811803

Proteomic Identification of the Galectin-1-Involved Molecular Pathways in Urinary Bladder Urothelial Carcinoma.

PubMed

Li, Chien-Feng; Shen, Kun-Hung; Chien, Lan-Hsiang; Huang, Cheng-Hao; Wu, Ting-Feng; He, Hong-Lin

2018-04-19

Among various heterogeneous types of bladder tumors, urothelial carcinoma is the most prevalent lesion. Some of the urinary bladder urothelial carcinomas (UBUCs) develop local recurrence and may cause distal invasion. Galectin-1 de-regulation significantly affects cell transformation, cell proliferation, angiogenesis, and cell invasiveness. In continuation of our previous investigation on the role of galectin-1 in UBUC tumorigenesis, in this study, proteomics strategies were implemented in order to find more galectin-1-associated signaling pathways. The results of this study showed that galectin-1 knockdown could induce 15 down-regulated proteins and two up-regulated proteins in T24 cells. These de-regulated proteins might participate in lipid/amino acid/energy metabolism, cytoskeleton, cell proliferation, cell-cell interaction, cell apoptosis, metastasis, and protein degradation. The aforementioned dys-regulated proteins were confirmed by western immunoblotting. Proteomics results were further translated to prognostic markers by analyses of biopsy samples. Results of cohort studies demonstrated that over-expressions of glutamine synthetase, alcohol dehydrogenase (NADP⁺), fatty acid binding protein 4, and toll interacting protein in clinical specimens were all significantly associated with galectin-1 up-regulation. Univariate analyses showed that de-regulations of glutamine synthetase and fatty acid binding protein 4 in clinical samples were respectively linked to disease-specific survival and metastasis-free survival.

Effect of recombinant galectin-1 on the growth of immortal rat chondrocyte on chitosan-coated PLGA scaffold.

PubMed

Chen, Shiang-Jiuun; Lin, Chien-Chung; Tuan, Wei-Cheh; Tseng, Ching-Shiow; Huang, Rong-Nan

2010-06-15

The effect of galectin-1 (GAL1) on the growth of immortal rat chondrocyte (IRC) on chitosan-modified PLGA scaffold is investigated. The experimental results showed that water absorption ratio of chitosan-modified PLGA scaffold was 70% higher than that of PLGA alone after immersion in ddH(2)O for 2 weeks, indicating that chitosan-modification significantly enhances the hydrophilicity of PLGA. The experimental results also showed that GALl efficiently and spontaneously coats the chitosan-PLGA scaffold surface to promote adhesion and growth of immortal rat chondrocyte (IRC). To investigate the effect of endogenous GAL1, the full-length GAL1 cDNAs were cloned and constructed into pcDNA3.1 vectors to generate a plasmid expressed in IRC (IRC-GAL1). The results showed that IRC-GAL1 growth was significantly higher than that of IRC on chitosan-PLGA scaffold. The GAL1-potentiated IRC growth on chitosan-PLGA scaffold was dose-dependently inhibited by TDG (specific inhibitor of GAL1 binding). These results strongly suggest that GAL1 is critical for enhancing IRC cell adhesion and growth on chitosan-PLGA scaffold. Moreover, GAL1-coating or expression tends to promote IRC cell-cell aggregation on chitosan-PLGA scaffold and significantly enhances IRC migration. These results suggest that GAL1 probably could induce tissue differentiation and facilitates cartilage reconstruction. In conclusion, the experimental results suggest that both GAL1 and chitosan are important for enhancing IRC cell adhesion and growth on PLGA scaffold, and GAL1 is a potential biomaterial for tissue engineering. (c) 2009 Wiley Periodicals, Inc.

Clinical significance of Tim3-positive T cell subsets in patients with multiple sclerosis.

PubMed

Feng, Xuemei; Feng, Juan

2016-12-01

The present study evaluated associations between the percentages of T cell immunoglobulin and mucin domain 3 (Tim3)-positive T cells and related cytokines and multiple sclerosis (MS). We collected peripheral blood samples from 30 MS patients and 30 healthy controls. Flow cytometry was used to determine the proportions of CD3 + Tim3 + , CD4 + Tim3 + , and CD4 + CD25 + Tim3 + in peripheral blood mononuclear cells (PBMCs) and related cell subsets. The serum concentrations of galectin-9, IL-17, and IFN-γ also were determined using enzyme-linked immunosorbent assays (ELISA). The percentages of Tim3-positive T cells in CD4 + and CD4 + CD25 + T cell subsets were significantly lower among MS patients than among controls. This difference was particularly evident in the CD4 + CD25(high) T cell subset. The proportions of CD4 + Tim3 + and CD4 + CD25 + Tim3 + cells in PBMCs were significantly lower in the MS group than in the control group, whereas no significant differences were detected regarding the percentages of CD3 + Tim3 + in PBMCs and T cell subsets. The serum concentrations of galectin-9, IL-17, and IFN-γ all were increased in MS patients compared with healthy controls. Our results support that Tim3 and related cytokines may be involved in the onset of MS. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of galectin binding by frontal affinity chromatography (FAC).

PubMed

Iwaki, Jun; Hirabayashi, Jun

2015-01-01

Frontal affinity chromatography (FAC) is a simple and versatile procedure enabling quantitative determination of diverse biological interactions in terms of dissociation constants (K d), even though these interactions are relatively weak. The method is best applied to glycans and their binding proteins, with the analytical system operating on the basis of highly reproducible isocratic elution by liquid chromatography. Its application to galectins has been successfully developed to characterize their binding specificities in detail. As a result, their minimal requirements for recognition of disaccharides, i.e., β-galactosides, as well as characteristic features of individual galectins, have been elucidated. In this chapter, we describe standard procedures to determine the K d's for interactions between a series of standard glycans and various galectins.

Quantifying protein interface footprinting by hydroxyl radical oxidation and molecular dynamics simulation: application to galectin-1.

PubMed

Charvátová, Olga; Foley, B Lachele; Bern, Marshall W; Sharp, Joshua S; Orlando, Ron; Woods, Robert J

2008-11-01

Biomolecular surface mapping methods offer an important alternative method for characterizing protein-protein and protein-ligand interactions in cases in which it is not possible to determine high-resolution three-dimensional (3D) structures of complexes. Hydroxyl radical footprinting offers a significant advance in footprint resolution compared with traditional chemical derivatization. Here we present results of footprinting performed with hydroxyl radicals generated on the nanosecond time scale by laser-induced photodissociation of hydrogen peroxide. We applied this emerging method to a carbohydrate-binding protein, galectin-1. Since galectin-1 occurs as a homodimer, footprinting was employed to characterize the interface of the monomeric subunits. Efficient analysis of the mass spectrometry data for the oxidized protein was achieved with the recently developed ByOnic (Palo Alto, CA) software that was altered to handle the large number of modifications arising from side-chain oxidation. Quantification of the level of oxidation has been achieved by employing spectral intensities for all of the observed oxidation states on a per-residue basis. The level of accuracy achievable from spectral intensities was determined by examination of mixtures of synthetic peptides related to those present after oxidation and tryptic digestion of galectin-1. A direct relationship between side-chain solvent accessibility and level of oxidation emerged, which enabled the prediction of the level of oxidation given the 3D structure of the protein. The precision of this relationship was enhanced through the use of average solvent accessibilities computed from 10 ns molecular dynamics simulations of the protein.

Galectin-3 maintains cell motility from the subventricular zone to the olfactory bulb

PubMed Central

Comte, Isabelle; Kim, Yongsoo; Young, Christopher C.; van der Harg, Judith M.; Hockberger, Philip; Bolam, Paul J.; Poirier, Françoise; Szele, Francis G.

2011-01-01

The adult brain subventricular zone (SVZ) produces neuroblasts that migrate through the rostral migratory stream (RMS) to the olfactory bulb (OB) in a specialized niche. Galectin-3 (Gal-3) regulates proliferation and migration in cancer and is expressed by activated macrophages after brain injury. The function of Gal-3 in the normal brain is unknown, but we serendipitously found that it was expressed by ependymal cells and SVZ astrocytes in uninjured mice. Ependymal cilia establish chemotactic gradients and astrocytes form glial tubes, which combine to aid neuroblast migration. Whole-mount preparations and electron microscopy revealed that both ependymal cilia and SVZ astrocytes were disrupted in Gal3−/− mice. Interestingly, far fewer new BrdU+ neurons were found in the OB of Gal3−/− mice, than in wild-type mice 2 weeks after labeling. However, SVZ proliferation and cell death, as well as OB differentiation rates were unaltered. This suggested that decreased migration in vivo was sufficient to decrease the number of new OB neurons. Two-photon time-lapse microscopy in forebrain slices confirmed decreased migration; cells were slower and more exploratory in Gal3−/− mice. Gal-3 blocking antibodies decreased migration and dissociated neuroblast cell–cell contacts, whereas recombinant Gal-3 increased migration from explants. Finally, we showed that expression of phosphorylated epidermal growth factor receptor (EGFR) was increased in Gal3−/− mice. These results suggest that Gal-3 is important in SVZ neuroblast migration, possibly through an EGFR-based mechanism, and reveals a role for this lectin in the uninjured brain. PMID:21693585

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pasek, Marta; Boeggeman, Elizabeth; Ramakrishnan, Boopathy

The expression of recombinant proteins in Escherichia coli often leads to inactive aggregated proteins known as the inclusion bodies. To date, the best available tool has been the use of fusion tags, including the carbohydrate-binding protein; e.g., the maltose-binding protein (MBP) that enhances the solubility of recombinant proteins. However, none of these fusion tags work universally with every partner protein. We hypothesized that galectins, which are also carbohydrate-binding proteins, may help as fusion partners in folding the mammalian proteins in E. coli. Here we show for the first time that a small soluble lectin, human galectin-1, one member of amore » large galectin family, can function as a fusion partner to produce soluble folded recombinant human glycosyltransferase, {beta}-1,4-galactosyltransferase-7 ({beta}4Gal-T7), in E. coli. The enzyme {beta}4Gal-T7 transfers galactose to xylose during the synthesis of the tetrasaccharide linker sequence attached to a Ser residue of proteoglycans. Without a fusion partner, {beta}4Gal-T7 is expressed in E. coli as inclusion bodies. We have designed a new vector construct, pLgals1, from pET-23a that includes the sequence for human galectin-1, followed by the Tev protease cleavage site, a 6x His-coding sequence, and a multi-cloning site where a cloned gene is inserted. After lactose affinity column purification of galectin-1-{beta}4Gal-T7 fusion protein, the unique protease cleavage site allows the protein {beta}4Gal-T7 to be cleaved from galectin-1 that binds and elutes from UDP-agarose column. The eluted protein is enzymatically active, and shows CD spectra comparable to the folded {beta}4Gal-T1. The engineered galectin-1 vector could prove to be a valuable tool for expressing other proteins in E. coli.« less

Modulation of ionotropic glutamate receptor function by vertebrate galectins.

PubMed

Copits, Bryan A; Vernon, Claire G; Sakai, Ryuichi; Swanson, Geoffrey T

2014-05-15

AMPA and kainate receptors are glutamate-gated ion channels whose function is known to be altered by a variety of plant oligosaccharide-binding proteins, or lectins, but the physiological relevance of this activity has been uncertain because no lectins with analogous allosteric modulatory effects have been identified in animals. We report here that members of the prototype galectin family, which are β-galactoside-binding lectins, exhibit subunit-specific allosteric modulation of desensitization of recombinant homomeric and heteromeric AMPA and kainate receptors. Galectin modulation of GluK2 kainate receptors was dependent upon complex oligosaccharide processing of N-glycosylation sites in the amino-terminal domain and downstream linker region. The sensitivity of GluA4 AMPA receptors to human galectin-1 could be enhanced by supplementation of culture media with uridine and N-acetylglucosamine (GlcNAc), precursors for the hexosamine pathway that supplies UDP-GlcNAc for synthesis of complex oligosaccharides. Neuronal kainate receptors in dorsal root ganglia were sensitive to galectin modulation, whereas AMPA receptors in cultured hippocampal neurons were insensitive, which could be a reflection of differential N-glycan processing or receptor subunit selectivity. Because glycan content of integral proteins can be modified dynamically, we postulate that physiological or pathological conditions in the CNS could arise in which galectins alter excitatory neurotransmission or neuronal excitability through their actions on AMPA or kainate receptors. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

A toolbox of lectins for translating the sugar code: the galectin network in phylogenesis and tumors.

PubMed

Kaltner, H; Gabius, H-J

2012-04-01

Lectin histochemistry has revealed cell-type-selective glycosylation. It is under dynamic and spatially controlled regulation. Since their chemical properties allow carbohydrates to reach unsurpassed structural diversity in oligomers, they are ideal for high density information coding. Consequently, the concept of the sugar code assigns a functional dimension to the glycans of cellular glycoconjugates. Indeed, multifarious cell processes depend on specific recognition of glycans by their receptors (lectins), which translate the sugar-encoded information into effects. Duplication of ancestral genes and the following divergence of sequences account for the evolutionary dynamics in lectin families. Differences in gene number can even appear among closely related species. The adhesion/growth-regulatory galectins are selected as an instructive example to trace the phylogenetic diversification in several animals, most of them popular models in developmental and tumor biology. Chicken galectins are identified as a low-level-complexity set, thus singled out for further detailed analysis. The various operative means for establishing protein diversity among the chicken galectins are delineated, and individual characteristics in expression profiles discerned. To apply this galectin-fingerprinting approach in histopathology has potential for refining differential diagnosis and for obtaining prognostic assessments. On the grounds of in vitro work with tumor cells a strategically orchestrated co-regulation of galectin expression with presentation of cognate glycans is detected. This coordination epitomizes the far-reaching physiological significance of sugar coding.

Modulation of ionotropic glutamate receptor function by vertebrate galectins

PubMed Central

Copits, Bryan A; Vernon, Claire G; Sakai, Ryuichi; Swanson, Geoffrey T

2014-01-01

AMPA and kainate receptors are glutamate-gated ion channels whose function is known to be altered by a variety of plant oligosaccharide-binding proteins, or lectins, but the physiological relevance of this activity has been uncertain because no lectins with analogous allosteric modulatory effects have been identified in animals. We report here that members of the prototype galectin family, which are β-galactoside-binding lectins, exhibit subunit-specific allosteric modulation of desensitization of recombinant homomeric and heteromeric AMPA and kainate receptors. Galectin modulation of GluK2 kainate receptors was dependent upon complex oligosaccharide processing of N-glycosylation sites in the amino-terminal domain and downstream linker region. The sensitivity of GluA4 AMPA receptors to human galectin-1 could be enhanced by supplementation of culture media with uridine and N-acetylglucosamine (GlcNAc), precursors for the hexosamine pathway that supplies UDP-GlcNAc for synthesis of complex oligosaccharides. Neuronal kainate receptors in dorsal root ganglia were sensitive to galectin modulation, whereas AMPA receptors in cultured hippocampal neurons were insensitive, which could be a reflection of differential N-glycan processing or receptor subunit selectivity. Because glycan content of integral proteins can be modified dynamically, we postulate that physiological or pathological conditions in the CNS could arise in which galectins alter excitatory neurotransmission or neuronal excitability through their actions on AMPA or kainate receptors. PMID:24614744

Inflamed In Vitro Retina: Cytotoxic Neuroinflammation and Galectin-3 Expression

PubMed Central

Bauer, Patrik Maximilian; Zalis, Marina Castro; Abdshill, Hodan; Deierborg, Tomas; Johansson, Fredrik; Englund-Johansson, Ulrica

2016-01-01

Background Disease progression in retinal neurodegeneration is strongly correlated to immune cell activation, which may have either a neuroprotective or neurotoxic effect. Increased knowledge about the immune response profile and retinal neurodegeneration may lead to candidate targets for treatments. Therefore, we have used the explanted retina as a model to explore the immune response and expression of the immune modulator galectin-3 (Gal-3), induced by the cultivation per se and after additional immune stimulation with lipopolysaccharide (LPS), and how this correlates with retinal neurotoxicity. Methods Post-natal mouse retinas were cultured in a defined medium. One group was stimulated with LPS (100 ng/ml, 24 h). Retinal architecture, apoptotic cell death, and micro- and macroglial activity were studied at the time of cultivation (0 days in vitro (DIV)) and at 3, 4 and 7 DIV using morphological staining, biochemical- and immunohistochemical techniques. Results Our results show that sustained activation of macro- and microglia, characterized by no detectable cytokine release and limited expression of Gal-3, is not further inducing apoptosis additional to the axotomy-induced apoptosis in innermost nuclear layer. An elevated immune response was detected after LPS stimulation, as demonstrated primarily by release of immune mediators (i.e. interleukin 2 (IL-2), IL-6, KC/GRO (also known as CLCX1) and tumour necrosis factor-α (TNF-α)), increased numbers of microglia displaying morphologies of late activation stages as well as Gal-3 expression. This was accompanied with increased apoptosis in the two additional nuclear layers, and damage to retinal gross architecture. Conclusion We demonstrate that an immune response characterized by sustained and increased release of cytokines, along with an increase in Gal-3 expression, is accompanied by significant increased neurotoxicity in the explanted retina. Further investigations using the current setting may lead to increased understanding on the mechanisms involved in neuronal loss in retinal neurodegenerations. PMID:27612287

Galectins in angiogenesis: consequences for gestation.

PubMed

Blois, Sandra M; Conrad, Melanie L; Freitag, Nancy; Barrientos, Gabriela

2015-04-01

Members of the galectin family have been shown to exert several roles in the context of reproduction. They contribute to placentation, maternal immune regulation and facilitate angiogenesis encompassing decidualisation and placenta formation during pregnancy. In the context of neo-vascularisation, galectins have been shown to augment signalling pathways that lead to endothelial cell activation, cell proliferation, migration and tube formation in vitro in addition to angiogenesis in vivo. Angiogenesis during gestation ensures not only proper foetal growth and development, but also maternal health. Consequently, restriction of placental blood flow has major consequences for both foetus and mother, leading to pregnancy diseases. In this review we summarise both the established and the emerging roles of galectin in angiogenesis and discuss the possible implications during healthy and pathological gestation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Secretion of Galectin-9 as a DAMP during Dengue Virus Infection in THP-1 Cells.

PubMed

Dapat, Isolde C; Pascapurnama, Dyshelly Nurkartika; Iwasaki, Hiroko; Labayo, Hannah Karen; Chagan-Yasutan, Haorile; Egawa, Shinichi; Hattori, Toshio

2017-07-28

Damage-associated molecular patterns (DAMPs) are endogenous cellular molecules released to the extracellular environment in response to stress conditions such as virus infection. Galectins are β-galactoside-binding proteins that are widely expressed in cells and tissues of the immune system, are localized in the cell cytoplasm, and have roles in inflammatory responses and immune responses against infection. Elevated levels of galectin-9 (Gal-9) in natural human infections have been documented in numerous reports. To investigate the effect of dengue virus (DENV) infection on expression of endogenous Gal-9, monocytic THP-1 cells were infected with varying doses of DENV-3 (multiplicity of infection (MOI) 0.01, 0.03 and 0.1) and incubated at varying time points (Day 1, Day 2, Day 3). Results showed augmentation of Gal-9 levels in the supernatant, reduction of Gal-9 levels in the cells and decreased expression of LGALS9 mRNA, while DENV-3 mRNA copies for all three doses remained stable through time. Dengue virus induced the secretion of Gal-9 as a danger response; in turn, Gal-9 and other inflammatory factors, and stimulated effector responses may have limited further viral replication. The results in this pilot experiment add to the evidence of Gal-9 as a potential DAMP.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Dongwen; Sun, Jianping; Zhao, Wei

The CRD domain of GRP from H. sapiens has been expressed, purified and crystallized and X-ray diffraction data have been collected to a resolution of 2.0 Å. Galectins are a family of animal lectins which share similar carbohydrate-recognition domains (CRDs) and an affinity for β-galactosides. A novel human galectin-related protein named GRP (galectin-related protein; previously known as HSPC159) comprises only one conserved CRD with 38 additional N-terminal residues. The C-terminal fragment of human GRP (GRP-C; residues 38–172) containing the CRD has been expressed and purified. The protein was crystallized using the hanging-drop vapour-diffusion method from a solution containing 2% PEGmore » 400 and 2M ammonium sulfate in 100 mM Tris–HCl buffer pH 7.5. Diffraction data were collected to a resolution limit of 2.0 Å at beamline 3W1A of Beijing Synchrotron Radiation Facility at 100 K. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 123.07, b = 96.67, c = 61.56 Å, β = 118.72°. The estimated Matthews coefficient was 2.6 Å{sup 3} Da{sup −1}, corresponding to 51.8% solvent content.« less

Effect of a low glycemic index diet versus a high-cereal fibre diet on markers of subclinical cardiac injury in healthy individuals with type 2 diabetes mellitus: An exploratory analysis of a randomized dietary trial.

PubMed

Ha, Vanessa; Viguiliouk, Effie; Kendall, Cyril W C; Balachandran, Bashyam; Jenkins, David J A; Kavsak, Peter A; Sievenpiper, John L

2017-12-01

Markers of subclinical cardiac injury are elevated in individuals with type 2 diabetes mellitus (T2DM) compared to healthy individuals. Low glycemic index (LGI) diets may improve both diabetes and cardiovascular risk but their effects on cardiac injury and fibrosis have not been previously studied. To test the effect of a LGI diet on markers of subclinical cardiac injury and fibrosis, we assessed the effect of a LGI compared with a high-cereal fibre diet on high-sensitivity cardiac troponin I (hs-cTnI) and galectin-3 in otherwise healthy individuals with T2DM in an exploratory analysis of a completed randomized trial. A total of 201 participants completed the trial and had measurements of hs-cTnI and galectin-3 at baseline and at trial completion. Participants were randomized to follow a LGI or a high-cereal fibre diet over a 6-month period. Treatment differences were tested using Analysis of Covariance (ANCOVA) with sex, baseline values, and diet x sex interaction included as covariates. In a completer's analysis, no significant differences were observed for change in hs-cTnI (-0.16ng/L vs. -0.22ng/L, p=0.713) and galectin-3 levels (0.64μg/L vs. 0.14μg/L, p=0.166) when a LGI diet was compared to a high-cereal fibre diet. The effect of a LGI diet was similar to a high-cereal fibre diet on hs-cTnI and galectin-3 levels in otherwise healthy individuals with T2DM over a 6-month period. Nevertheless, in the absence of any adverse effects, LGI diets remain an option for diabetes and cardiovascular disease risk management. ClinicalTrials.gov identifier: NCT00438698. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Pharmacoproteomics of a metalloproteinase hydroxamate inhibitor in breast cancer cells: dynamics of membrane type 1 matrix metalloproteinase-mediated membrane protein shedding.

PubMed

Butler, Georgina S; Dean, Richard A; Tam, Eric M; Overall, Christopher M

2008-08-01

Broad-spectrum matrix metalloproteinase (MMP) inhibitors (MMPI) were unsuccessful in cancer clinical trials, partly due to side effects resulting from limited knowledge of the full repertoire of MMP substrates, termed the substrate degradome, and hence the in vivo functions of MMPs. To gain further insight into the degradome of MMP-14 (membrane type 1 MMP) an MMPI, prinomastat (drug code AG3340), was used to reduce proteolytic processing and ectodomain shedding in human MDA-MB-231 breast cancer cells transfected with MMP-14. We report a quantitative proteomic evaluation of the targets and effects of the inhibitor in this cell-based system. Proteins in cell-conditioned medium (the secretome) and membrane fractions with levels that were modulated by the MMPI were identified by isotope-coded affinity tag (ICAT) labeling and tandem mass spectrometry. Comparisons of the expression of MMP-14 with that of a vector control resulted in increased MMP-14/vector ICAT ratios for many proteins in conditioned medium, indicating MMP-14-mediated ectodomain shedding. Following MMPI treatment, the MMPI/vehicle ICAT ratio was reversed, suggesting that MMP-14-mediated shedding of these proteins was blocked by the inhibitor. The reduction in shedding or the release of substrates from pericellular sites in the presence of the MMPI was frequently accompanied by the accumulation of the protein in the plasma membrane, as indicated by high MMPI/vehicle ICAT ratios. Considered together, this is a strong predictor of biologically relevant substrates cleaved in the cellular context that led to the identification of many undescribed MMP-14 substrates, 20 of which we validated biochemically, including DJ-1, galectin-1, Hsp90alpha, pentraxin 3, progranulin, Cyr61, peptidyl-prolyl cis-trans isomerase A, and dickkopf-1. Other proteins with altered levels, such as Kunitz-type protease inhibitor 1 and beta-2-microglobulin, were not substrates in biochemical assays, suggesting an indirect affect of the MMPI, which might be important in drug development as biomarkers or, in preclinical phases, to predict systemic drug actions and adverse side effects. Hence, this approach describes the dynamic pattern of cell membrane ectodomain shedding and its perturbation upon metalloproteinase drug treatment.

Proteome screening of pleural effusions identifies galectin 1 as a diagnostic biomarker and highlights several prognostic biomarkers for malignant mesothelioma.

PubMed

Mundt, Filip; Johansson, Henrik J; Forshed, Jenny; Arslan, Sertaç; Metintas, Muzaffer; Dobra, Katalin; Lehtiö, Janne; Hjerpe, Anders

2014-03-01

Malignant mesothelioma is an aggressive asbestos-induced cancer, and affected patients have a median survival of approximately one year after diagnosis. It is often difficult to reach a conclusive diagnosis, and ancillary measurements of soluble biomarkers could increase diagnostic accuracy. Unfortunately, few soluble mesothelioma biomarkers are suitable for clinical application. Here we screened the effusion proteomes of mesothelioma and lung adenocarcinoma patients to identify novel soluble mesothelioma biomarkers. We performed quantitative mass-spectrometry-based proteomics using isobaric tags for quantification and used narrow-range immobilized pH gradient/high-resolution isoelectric focusing (pH 4-4.25) prior to analysis by means of nano liquid chromatography coupled to MS/MS. More than 1,300 proteins were identified in pleural effusions from patients with malignant mesothelioma (n = 6), lung adenocarcinoma (n = 6), or benign mesotheliosis (n = 7). Data are available via ProteomeXchange with identifier PXD000531. The identified proteins included a set of known mesothelioma markers and proteins that regulate hallmarks of cancer such as invasion, angiogenesis, and immune evasion, plus several new candidate proteins. Seven candidates (aldo-keto reductase 1B10, apolipoprotein C-I, galectin 1, myosin-VIIb, superoxide dismutase 2, tenascin C, and thrombospondin 1) were validated by enzyme-linked immunosorbent assays in a larger group of patients with mesothelioma (n = 37) or metastatic carcinomas (n = 25) and in effusions from patients with benign, reactive conditions (n = 16). Galectin 1 was identified as overexpressed in effusions from lung adenocarcinoma relative to mesothelioma and was validated as an excellent predictor for metastatic carcinomas against malignant mesothelioma. Galectin 1, aldo-keto reductase 1B10, and apolipoprotein C-I were all identified as potential prognostic biomarkers for malignant mesothelioma. This analysis of the effusion proteome furthers our understanding of malignant mesothelioma, identified galectin 1 as a potential diagnostic biomarker, and highlighted several possible prognostic biomarkers of this disease.

Galectin-3 controls the response of microglial cells to limit cuprizone-induced demyelination.

PubMed

Hoyos, H C; Rinaldi, M; Mendez-Huergo, S P; Marder, M; Rabinovich, G A; Pasquini, J M; Pasquini, L A

2014-02-01

Galectin-3 (Gal-3) is a β-galactoside-binding lectin that plays an important role in inflammatory and neurodegenerative diseases. Cuprizone (CPZ)-induced demyelination is characterized by the loss of mature oligodendrocytes (OLG) by apoptosis, myelin sheath degeneration and recruitment of microglia and astrocytes to the lesioned area. We compared CPZ-induced demyelination of 8-week-old Lgals3(-/-) vs WT mice. Lgals3(-/-) mice displayed a similar susceptibility to CPZ-induced demyelination up to the fifth week, as evaluated by MBP immunostaining and electronic microscopy. However, OLG progenitors (OPC) generated in CPZ-treated Lgals3(-/-) mice showed diminished arborization, suggesting decreased ability of these cells to differentiate. Surprisingly, while WT mice experienced spontaneous remyelination in the fifth week of CPZ treatment-even though the CPZ diet was maintained up to sixth week-Lgals3(-/-) mice lacked this capacity and suffered continuous demyelination up to the sixth week, accompanied by pronounced astroglial activation. Moreover, after 2weeks of CPZ treatment, WT and Lgals3(-/-) mice showed lower innate anxiety as compared with respective naive mice, but only CPZ-treated Lgals3(-/-) mice showed decreased locomotor activity and exhibited spatial working memory impairment. Expression of Gal-3 increased during CPZ-induced demyelination in microglia but not in astrocytes. While CPZ-treated WT mice displayed heightened microglial activation associated with ED1 expression and pronounced upregulation of the phagocytic receptor TREM-2b, this effect was not observed in CPZ-treated Lgals3(-/-) mice which, in spite of showing an increased number of microglia, these cells evidenced caspase-3 activation. Our results indicate that Gal-3 is expressed in microglial cells to modulate their phenotype, facilitating the onset of remyelination and OLG differentiation. © 2013.

Split sample comparison of a liquid-based method and conventional smears in thyroid fine needle aspiration.

PubMed

Jung, Chan-Kwon; Lee, Ahwon; Jung, Eun-Sun; Choi, Yeong-Jin; Jung, So-Lyung; Lee, Kyo-Young

2008-01-01

To compare the efficacy of the SurePath (SP) vs. conventional smears (CS) in fine needle aspiration (FNA) of thyroid gland lesions. A total of 193 FNA cases with thyroid nodules were studied. Samples from ultrasound-guided FNA were split to prepare CS and SP slides. The diagnostic categories of unsatisfactory, benign, atypical and malignant were compared. Galectin-3 immunostaining was performed on SP slides. Some differences were found between the cytomorphology of CS and SP. SP slides showed more increased cellularity and more clustered tissue fragments. On SP slides, nuclear detail and nucleoli were more easily detected and nuclear irregularity was very useful for the diagnosis of papillary carcinoma. SP showed a trend toward a lower proportion of atypical category. The overall sensitivity of FNA in diagnosing thyroid neoplasm was 90.9% for CS and 93.9% for SP. Most lesions (73%) diagnosed as papillary carcinoma after surgery showed positive staining of galectin-3. The SP method showed easy evaluation of cytomorphologic features and consistent specimen quality and appeared to be more useful in diagnosing the suspicious cases. Moreover, it offered the possibility of adjunctive immunocytochemistry on the same sample.

Molecular galactose-galectin association in neuroblastoma cells: An unconventional tool for qualitative/quantitative screening.

PubMed

Pastorino, Fabio; Ponzoni, Mirco; Simone, Giuseppina

2017-05-01

Galectin decorates the cell membrane and forms an extracellular molecular association with galactoside units. Here, galactoside probes have been used to study galectin expression in neuroblastoma cells. The hypothesis behind this investigation has been that the molecular mechanisms by which glycans modulate neural metastatic cells involve a protein-carbohydrate association, galectin-galactose. Preliminary screening to validate the hypothesis has been performed with galactose moieties anchored to beads. The molecular association has been studied by FACS. In vitro experiments reveal the molecular binding preferences of the metastatic neuroblastoma cells. Ex vivo, the galactose probes discriminate healthy tissues. The unconventional assay in microfluidics used in this study displayed results analogous to the above (GI-LI-N cell capture efficiency overcomes IMR-32). At the point of equilibrium of shear and binding forces, the capture yield inside the chamber was measured to 60 ± 4.4% in GI-LI-N versus 40 ± 2.1% in IMR-32. Staining of the fished cells and subsequent conjugation with red beads bearing the galactose also have evidenced that microfluidics can be used to study and quantify the molecular association of galectin-galactose. Most importantly, a crucial insight for obtaining single-cell qualitative/quantitative glycome analysis has been achieved. Finally, the specificity of the assay performed in microfluidics is demonstrated by comparing GI-LI-N fishing efficiency in galactose and fucose environments. The residual adhesion to fucose confirmed the existence of receptors for this glycan and that its eventual unspecific binding (i.e. due to electrostatic interactions) is insignificant compared with the molecular binding. Identification and understanding of this mechanism of discrimination can be relevant for diagnostic monitoring and for producing probes tailored to interfere with galectin activities associated with the malignant phenotype. Besides, the given strategy has implications for the rational design of galectin-specific ligands. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Structure of the mouse galectin-4 N-terminal carbohydrate-recognition domain reveals the mechanism of oligosaccharide recognition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krejciríková, Veronika; Pachl, Petr; Fábry, Milan

2011-11-18

Galectin-4, a member of the tandem-repeat subfamily of galectins, participates in cell-membrane interactions and plays an important role in cell adhesion and modulation of immunity and malignity. The oligosaccharide specificity of the mouse galectin-4 carbohydrate-recognition domains (CRDs) has been reported previously. In this work, the structure and binding properties of the N-terminal domain CRD1 were further investigated and the crystal structure of CRD1 in complex with lactose was determined at 2.1 {angstrom} resolution. The lactose-binding affinity was characterized by fluorescence measurements and two lactose-binding sites were identified: a high-affinity site with a K{sub d} value in the micromolar range (K{submore » d1} = 600 {+-} 70 {mu}M) and a low-affinity site with K{sub d2} = 28 {+-} 10 mM.« less

Galectin-9 Signaling through TIM-3 Is Involved in Neutrophil-Mediated Gram-Negative Bacterial Killing: An Effect Abrogated within the Cystic Fibrosis Lung

PubMed Central

Vega-Carrascal, Isabel; Bergin, David A.; McElvaney, Oliver J.; McCarthy, Cormac; Banville, Nessa; Pohl, Kerstin; Hirashima, Mitsuomi; Kuchroo, Vijay K.; Reeves, Emer P.; McElvaney, Noel G.

2016-01-01

The T cell Ig and mucin domain–containing molecule (TIM) family of receptors have emerged as potential therapeutic targets to correct abnormal immune function in chronic inflammatory conditions. TIM-3 serves as a functional receptor in structural cells of the airways and via the ligand galectin-9 (Gal-9) can modulate the inflammatory response. The aim of this study was to investigate TIM-3 expression and function in neutrophils, focusing on its potential role in cystic fibrosis (CF) lung disease. Results revealed that TIM-3 mRNA and protein expression values of circulating neutrophils were equal between healthy controls (n = 20) and people with CF (n = 26). TIM-3 was detected on resting neutrophil membranes by FACS analysis, and expression levels significantly increased post IL-8 or TNF-α exposure (p < 0.05). Our data suggest a novel role for TIM-3/Gal-9 signaling involving modulation of cytosolic calcium levels. Via TIM-3 interaction, Gal-9 induced neutrophil degranulation and primed the cell for enhanced NADPH oxidase activity. Killing of Pseudomonas aeruginosa was significantly increased upon bacterial opsonization with Gal-9 (p < 0.05), an effect abrogated by blockade of TIM-3 receptors. This mechanism appeared to be Gram-negative bacteria specific and mediated via Gal-9/ LPS binding. Additionally, we have demonstrated that neutrophil TIM-3/Gal-9 signaling is perturbed in the CF airways due to proteolytic degradation of the receptor. In conclusion, results suggest a novel neutrophil defect potentially contributing to the defective bacterial clearance observed in the CF airways and suggest that manipulation of the TIM-3 signaling pathway may be of therapeutic value in CF, preferably in conjunction with antiprotease treatment. PMID:24477913

Galectin-3, a biomarker linking oxidative stress and inflammation with the clinical outcomes of patients with atherothrombosis.

PubMed

Madrigal-Matute, Julio; Lindholt, Jes Sandal; Fernandez-Garcia, Carlos Ernesto; Benito-Martin, Alberto; Burillo, Elena; Zalba, Guillermo; Beloqui, Oscar; Llamas-Granda, Patricia; Ortiz, Alberto; Egido, Jesus; Blanco-Colio, Luis Miguel; Martin-Ventura, Jose Luis

2014-08-05

Galectin-3 (Gal-3) participates in different mechanisms involved in atherothrombosis, such as inflammation, proliferation, or macrophage chemotaxis. Thus, there have been committed intensive efforts to elucidate the function of Gal-3 in cardiovascular (CV) diseases. The role of Gal-3 as a circulating biomarker has been demonstrated in patients with heart failure, but its importance as a biomarker in atherothrombosis is still unknown. Because Gal-3 is involved in monocyte-to-macrophage transition, we used fresh isolated monocytes and the in vitro model of macrophage differentiation of THP-1 cells stimulated with phorbol myristate acetate (PMA). Gal-3 release is increased by PMA in human monocytes and macrophages, a process involving exosomes and regulated by reactive oxygen species/NADPH oxidase activity. In asymptomatic subjects (n=199), Gal-3 plasma levels are correlated with NADPH oxidase activity in peripheral blood mononuclear cells (r=0.476; P<0.001) and carotid intima-media thickness (r=0.438; P<0.001), a surrogate marker of atherosclerosis. Accordingly, Gal-3 plasma concentrations are increased in patients with carotid atherosclerosis (n=158), compared to control subjects (n=115; 14.3 [10.7 to 16.9] vs. 10.4 [8.6 to 12.5] ng/mL; P<0.001). Finally, on a 5-year follow-up study in patients with peripheral artery disease, Gal-3 concentrations are significantly and independently associated with an increased risk for CV mortality (hazard ratio=2.24, 95% confidence interval: 1.06 to 4.73, P<0.05). Gal-3 extracellular levels could reflect key underlying mechanisms involved in atherosclerosis etiology, development, and plaque rupture, such as inflammation, infiltration of circulating cells and oxidative stress. Moreover, circulating Gal-3 concentrations are associated with clinical outcomes in patients with atherothrombosis. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

The role of galectin-1 in in vitro and in vivo photodynamic therapy with a galactodendritic porphyrin.

PubMed

Pereira, Patrícia M R; Silva, Sandrina; Ramalho, José S; Gomes, Célia M; Girão, Henrique; Cavaleiro, José A S; Ribeiro, Carlos A F; Tomé, João P C; Fernandes, Rosa

2016-11-01

Conventional photodynamic agents used in clinic are porphyrin-based photosensitizers. However, they have low tumour selectivity, which may induce unwanted side-effects and damage to healthy tissues. In this study, we used a porphyrin with dendritic units of galactose (PorGal 8 ) developed by us, which can target the galactose-binding protein, galectin-1, known to be overexpressed in many tumour tissues. In vitro and in vivo studies had been conducted for the validation of PorGal 8 effectiveness. We showed a specific uptake of PorGal 8 and induction of apoptotic cell death by generating oxidative stress and alterations in the cytoskeleton of bladder cancer cells overexpressing galectin-1. We further validated the photodynamic efficiency of PorGal 8 in athymic nude mice (Balb/c nu/nu) bearing subcutaneously implanted luciferase-positive bladder cancer xenografts, overexpressing galectin-1 protein. PorGal 8 (5 μmol/kg, intraperitoneal), injected 24 h before light delivery (50.4 J/cm 2 ), inhibited tumour growth. We conclude that the use of PorGal 8 enables selective target and cytotoxicity by photodynamic therapy in cancer cells overexpressing galectin-1, preventing undesired phototoxicity in the surrounding healthy tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

Protective effect of Galectin-9 in murine model of lung emphysema: Involvement of neutrophil migration and MMP-9 production

PubMed Central

Horio, Yuko; Ichiyasu, Hidenori; Kojima, Keisuke; Saita, Naoki; Migiyama, Yohei; Iriki, Toyohisa; Fujii, Kazuhiko; Niki, Toshiro; Hirashima, Mitsuomi; Kohrogi, Hirotsugu

2017-01-01

Purpose Chronic obstructive pulmonary disease (COPD) is characterized by irreversible airflow obstruction and pulmonary emphysema. Persistent inflammation and remodeling of the lungs and airways result in reduced lung function and a lower quality of life. Galectin (Gal)-9 plays a crucial role as an immune modulator in various diseases. However, its role in the pathogenesis of pulmonary emphysema is unknown. This study investigates whether Gal-9 is involved in pulmonary inflammation and changes in emphysema in a porcine pancreatic elastase (PPE)-induced emphysema model. Materials and methods Gal-9 was administered to mice subcutaneously once daily from 1 day before PPE instillation to day 5. During the development of emphysema, lung tissue and bronchoalveolar lavage fluid (BALF) were collected. Histological and cytological findings, concentrations of chemokines and matrix metalloproteinases (MMPs) in the BALF, and the influence of Gal-9 treatment on neutrophils were analyzed. Results Gal-9 suppressed the pathological changes of PPE-induced emphysema. The mean linear intercept (Lm) of Gal-9-treated emphysema mice was significantly lower than that of PBS-treated emphysema mice (66.1 ± 3.3 μm vs. 118.8 ± 14.8 μm, respectively; p < 0.01). Gal-9 decreased the number of neutrophils and levels of MMP-9, MMP-2 and tissue inhibitor of metalloproteinases (TIMP)-1 in the BALF. The number of neutrophils in the BALF correlated significantly with MMPs levels. Interestingly, Gal-9 pretreatment in vitro inhibited the chemotactic activity of neutrophils and MMP-9 production from neutrophils. Furthermore, in Gal-9-deficient mice, PPE-induced emphysema progressed significantly compared with that in wild–type (WT) mice (108.7 ± 6.58 μm vs. 77.19 ± 6.97 μm, respectively; p < 0.01). Conclusions These results suggest that Gal-9 protects PPE-induced inflammation and emphysema by inhibiting the infiltration of neutrophils and decreasing MMPs levels. Exogenous Gal-9 could be a potential therapeutic agent for COPD. PMID:28704475

The Role of CD56 in Thyroid Fine Needle Aspiration Cytology: A Pilot Study Performed on Liquid Based Cytology

PubMed Central

Bizzarro, Tommaso; Martini, Maurizio; Marrocco, Carla; D’Amato, Donato; Traini, Emanuela; Lombardi, Celestino Pio; Pontecorvi, Alfredo; Fadda, Guido; Larocca, Luigi Maria; Rossi, Esther Diana

2015-01-01

Background Fine needle aspiration Cytology (FNAC) fulfills a reliable role in the evaluation of thyroid lesions. Although the majority of nodules are quite easily diagnosed as benign or malignant, 30% of them represent an indeterminate category whereby the application of ancillary techniques (i.e. immunocytochemistry-ICC and molecular testing) has been encouraged. The search for a specific immunomarker of malignancy sheds light on a huge number of ICC stains although none of them attempt to yield 100% conclusive results. Our aim was to define in a pilot study on thyroid FNAC whether CD56 might be a valid marker also in comparison with HBME-1 and Galectin-3. Materials and Methods Inasmuch as this is the largest pilot study using only liquid based cytology (LBC), we selected all the cases only in the categories of benign nodules (BN) and positive for malignancy (PM) for validation purposes. Eighty-five consecutive (including 50 PM and 35 BN) out of 950 thyroid FNACs had surgical follow-up. The ICC panel (HBME-1, Galectin-3 and CD56) was carried out on LBC and histology. Results All BNs and PMs were histological confirmed. CD56 was negative in 96% of the PM while 68.5% of the BNs showed cytoplasmic positivity for this marker, with an overall high sensitivity (96%) but lower specificity (69%). In specific, our 96% of the PMs did not show any follicular cell with CD56 expression. Different ICC combinations were evaluated showing that the panel made up of CD56 plus HBME-1 and Galectin-3 had the highest sensitivity (98%) and specificity (86%). Conclusions Our pilot study suggests that CD56 may be a good marker for ruling out PTC and its variants. The low specificity suggests that an immunopanel including also HBME-1 and Galectin-3 could obtain the highest diagnostic accuracy in thyroid lesions. Our results suggest that CD56 may be a feasible additional marker for identifying malignancies also in the FNs and SMs. PMID:26186733

Galectin-3 is a non-classic RNA binding protein that stabilizes the mucin MUC4 mRNA in the cytoplasm of cancer cells.

PubMed

Coppin, Lucie; Vincent, Audrey; Frénois, Frédéric; Duchêne, Belinda; Lahdaoui, Fatima; Stechly, Laurence; Renaud, Florence; Villenet, Céline; Van Seuningen, Isabelle; Leteurtre, Emmanuelle; Dion, Johann; Grandjean, Cyrille; Poirier, Françoise; Figeac, Martin; Delacour, Delphine; Porchet, Nicole; Pigny, Pascal

2017-03-06

Pancreatic cancer cells express high levels of MUC1, MUC4 and MUC16 mRNAs that encode membrane-bound mucins. These mRNAs share unusual features such as a long half-life. However, it remains unknown how mucin mRNA stability is regulated. Galectin-3 (Gal-3) is an endogenous lectin playing important biological functions in epithelial cells. Gal-3 is encoded by LGALS3 which is up-regulated in pancreatic cancer. Despite the absence of a RNA-recognition motif, Gal-3 interacts indirectly with pre-mRNAs in the nucleus and promotes constitutive splicing. However a broader role of Gal-3 in mRNA fate is unexplored. We report herein that Gal-3 increases MUC4 mRNA stability through an intermediate, hnRNP-L which binds to a conserved CA repeat element in the 3'UTR in a Gal-3 dependent manner and also controls Muc4 mRNA levels in epithelial tissues of Gal3 -/- mice. Gal-3 interacts with hnRNP-L in the cytoplasm, especially during cell mitosis, but only partly associates with protein markers of P-Bodies or Stress Granules. By RNA-IP plus RNA-seq analysis and imaging, we demonstrate that Gal-3 binds to mature spliced MUC4 mRNA in the perinuclear region, probably in hnRNP-L-containing RNA granules. Our findings highlight a new role for Gal-3 as a non-classic RNA-binding protein that regulates MUC4 mRNA post-transcriptionally.

Galectin-3 is a non-classic RNA binding protein that stabilizes the mucin MUC4 mRNA in the cytoplasm of cancer cells

PubMed Central

Coppin, Lucie; Vincent, Audrey; Frénois, Frédéric; Duchêne, Belinda; Lahdaoui, Fatima; Stechly, Laurence; Renaud, Florence; Villenet, Céline; Seuningen, Isabelle Van; Leteurtre, Emmanuelle; Dion, Johann; Grandjean, Cyrille; Poirier, Françoise; Figeac, Martin; Delacour, Delphine; Porchet, Nicole; Pigny, Pascal

2017-01-01

Pancreatic cancer cells express high levels of MUC1, MUC4 and MUC16 mRNAs that encode membrane-bound mucins. These mRNAs share unusual features such as a long half-life. However, it remains unknown how mucin mRNA stability is regulated. Galectin-3 (Gal-3) is an endogenous lectin playing important biological functions in epithelial cells. Gal-3 is encoded by LGALS3 which is up-regulated in pancreatic cancer. Despite the absence of a RNA-recognition motif, Gal-3 interacts indirectly with pre-mRNAs in the nucleus and promotes constitutive splicing. However a broader role of Gal-3 in mRNA fate is unexplored. We report herein that Gal-3 increases MUC4 mRNA stability through an intermediate, hnRNP-L which binds to a conserved CA repeat element in the 3′UTR in a Gal-3 dependent manner and also controls Muc4 mRNA levels in epithelial tissues of Gal3−/− mice. Gal-3 interacts with hnRNP-L in the cytoplasm, especially during cell mitosis, but only partly associates with protein markers of P-Bodies or Stress Granules. By RNA-IP plus RNA-seq analysis and imaging, we demonstrate that Gal-3 binds to mature spliced MUC4 mRNA in the perinuclear region, probably in hnRNP-L-containing RNA granules. Our findings highlight a new role for Gal-3 as a non-classic RNA-binding protein that regulates MUC4 mRNA post-transcriptionally. PMID:28262838

A galectin from Eriocheir sinensis functions as pattern recognition receptor enhancing microbe agglutination and haemocytes encapsulation.

PubMed

Wang, Mengqiang; Wang, Lingling; Huang, Mengmeng; Yi, Qilin; Guo, Ying; Gai, Yunchao; Wang, Hao; Zhang, Huan; Song, Linsheng

2016-08-01

Galectins are a family of β-galactoside binding lectins that function as pattern recognition receptors (PRRs) in innate immune system of both vertebrates and invertebrates. The cDNA of Chinese mitten crab Eriocheir sinensis galectin (designated as EsGal) was cloned via rapid amplification of cDNA ends (RACE) technique based on expressed sequence tags (ESTs) analysis. The full-length cDNA of EsGal was 999 bp. Its open reading frame encoded a polypeptide of 218 amino acids containing a GLECT/Gal-bind_lectin domain and a proline/glycine rich low complexity region. The deduced amino acid sequence and domain organization of EsGal were highly similar to those of crustacean galectins. The mRNA transcripts of EsGal were found to be constitutively expressed in a wide range of tissues and mainly in hepatopancreas, gill and haemocytes. The mRNA expression level of EsGal increased rapidly and significantly after crabs were stimulated by different microbes. The recombinant EsGal (rEsGal) could bind various pathogen-associated molecular patterns (PAMPs), including lipopolysaccharide (LPS), peptidoglycan (PGN) and glucan (GLU), and exhibited strong activity to agglutinate Escherichia coli, Vibrio anguillarum, Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus and Pichia pastoris, and such agglutinating activity could be inhibited by both d-galactose and α-lactose. The in vitro encapsulation assay revealed that rEsGal could enhance the encapsulation of haemocytes towards agarose beads. These results collectively suggested that EsGal played crucial roles in the immune recognition and elimination of pathogens and contributed to the innate immune response against various microbes in crabs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Detection of Differentially Expressed Wound-Healing–Related Glycogenes in Galectin-3–Deficient Mice

PubMed Central

Saravanan, Chandrassegar; Cao, Zhiyi; Head, Steven R.; Panjwani, Noorjahan

2010-01-01

Purpose A prior study showed that exogenous galectin-3 (Gal-3) stimulates re-epithelialization of corneal wounds in wild-type (Gal-3+/+) mice but, surprisingly, not in galectin-3–deficient (Gal-3−/−) mice. In an effort to understand why the injured corneas of Gal-3−/− mice are unresponsive to exogenous Gal-3, the present study was designed to determine whether genes encoding the enzymes that regulate the synthesis of glycan ligands of Gal-3 are differentially expressed in Gal-3−/− corneas compared with the Gal-3+/+ corneas. Methods Glycogene microarray technology was used to identify differentially expressed glycosyltransferases in healing Gal-3+/+ and Gal-3−/− corneas. Results Of ~2000 glycogenes on the array, the expression of 8 was upregulated and that of 14 was downregulated more than 1.3-fold in healing Gal-3−/− corneas. A galactosyltransferase, β3GalT5, which has the ability to synthesize Gal-3 ligands was markedly downregulated in healing Gal-3−/− corneas. The genes for polypeptide galactosaminyltransferases (ppGalNAcT-3 and -7) that are known to initiate O-linked glycosylation and N-aspartyl-β-glucosaminidase, which participates in the removal of N-glycans, were found to be upregulated in healing Gal-3−/− corneas. Microarray data were validated by qRT-PCR. Conclusions Based on the known functions of the differentially expressed glycogenes, it appears that the glycan structures on glycoproteins and glycolipids, synthesized as a result of the differential glycogene expression pattern in healing Gal-3−/− corneas may lead to the downregulation of specific counterreceptors for Gal-3. This may explain, at least in part, why, unlike healing Gal-3+/+ corneas, the healing Gal-3−/− corneas are unresponsive to the stimulatory effect of exogenous Gal-3 on re-epithelialization of corneal wounds. PMID:19643959

Cellular Prion Protein Combined with Galectin-3 and -6 Affects the Infectivity Titer of an Endogenous Retrovirus Assayed in Hippocampal Neuronal Cells

PubMed Central

Shin, Hae-Young; Goto, Joy J.; Carp, Richard I.; Choi, Eun-Kyoung; Kim, Yong-Sun

2016-01-01

Prion diseases are infectious and fatal neurodegenerative diseases which require the cellular prion protein, PrPC, for development of diseases. The current study shows that the PrPC augments infectivity and plaque formation of a mouse endogenous retrovirus, MuLV. We have established four neuronal cell lines expressing mouse PrPC, PrP+/+; two express wild type PrPC (MoPrPwild) and the other two express mutant PrPC (MoPrPmut). Infection of neuronal cells from various PrP+/+ and PrP-/- (MoPrPKO) lines with MuLV yielded at least three times as many plaques in PrP+/+ than in PrP-/-. Furthermore, among the four PrP+/+ lines, one mutant line, P101L, had at least 2.5 times as many plaques as the other three PrP+/+ lines. Plaques in P101L were four times larger than those in other PrP+/+ lines. Colocalization of PrP and CAgag was seen in MuLV-infected PrP+/+ cells. In the PrP-MuLV interaction, the involvement of galectin-3 and -6 was observed by immunoprecipitation with antibody to PrPC. These results suggest that PrPC combined with galectin-3 and -6 can act as a receptor for MuLV. P101L, the disease form of mutant PrPC results suggest the genetic mutant form of PrPC may be more susceptible to viral infection. PMID:27936017

Formation of the 67-kDa laminin receptor by acylation of the precursor.

PubMed

Butò, S; Tagliabue, E; Ardini, E; Magnifico, A; Ghirelli, C; van den Brûle, F; Castronovo, V; Colnaghi, M I; Sobel, M E; Ménard, S

1998-06-01

Even though the involvement of the 67-kDa laminin receptor (67LR) in tumor invasiveness has been clearly demonstrated, its molecular structure remains an open problem, since only a full-length gene encoding a 37-kDa precursor protein (37LRP) has been isolated so far. A pool of recently obtained monoclonal antibodies directed against the recombinant 37LRP molecule was used to investigate the processing that leads to the formation of the 67-kDa molecule. In soluble extracts of A431 human carcinoma cells, these reagents recognize the precursor molecule as well as the mature 67LR and a 120-kDa molecule. The recovery of these proteins was found to be strikingly dependent upon the cell solubilization conditions: the 67LR is soluble in NP-40-lysis buffer whereas the 37LRP is NP-40-insoluble. Inhibition of 67LR formation by cerulenin indicates that acylation is involved in the processing of the receptor. It is likely a palmitoylation process, as indicated by sensitivity of NP-40-soluble extracts to hydroxylamine treatment. Immunoblotting assays performed with a polyclonal serum directed against galectin3 showed that both the 67- and the 120-kDa proteins carry galectin3 epitopes whereas the 37LRP does not. These data suggest that the 67LR is a heterodimer stabilized by strong intramolecular hydrophobic interactions, carried by fatty acids bound to the 37LRP and to a galectin3 cross-reacting molecule.

New Pharmacologic Agents That Target Inflammation and Fibrosis in Nonalcoholic Steatohepatitis-Related Kidney Disease.

PubMed

Musso, Giovanni; De Michieli, Franco; Bongiovanni, Daria; Parente, Renato; Framarin, Luciana; Leone, Nicola; Berrutti, Mara; Gambino, Roberto; Cassader, Maurizio; Cohney, Solomon; Paschetta, Elena

2017-07-01

Epidemiologic data show an association between the prevalence and severity of nonalcoholic fatty liver disease and the incidence and stage of chronic kidney disease (CKD); furthermore, nonalcoholic steatohepatitis (NASH)-related cirrhosis has a higher risk of renal failure, a greater necessity for simultaneous liver-kidney transplantation, and a poorer renal outcome than cirrhosis of other etiologies even after simultaneous liver-kidney transplantation. These data suggest that NASH and CKD share common proinflammatory and profibrotic mechanisms of progression, which are targeted incompletely by current treatments. We reviewed therapeutic approaches to late preclinical/early clinical stage of development in NASH and/or CKD, focusing on anti-inflammatory and antifibrotic treatments, which could slow the progression of both disease conditions. Renin inhibitors and angiotensin-converting enzyme-2 activators are new renin-angiotensin axis modulators that showed incremental advantages over angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers in preclinical models. Novel, potent, and selective agonists of peroxisome proliferator-activated receptors and of farnesoid X receptor, designed to overcome limitations of older compounds, showed promising results in clinical trials. Epigenetics, heat stress response, and common effectors of redox regulation also were subjected to intensive research, and the gut was targeted by several approaches, including synbiotics, antilipopolysaccharide antibodies, Toll-like receptor-4 antagonists, incretin mimetics, and fibroblast growth factor 19 analogs. Promising anti-inflammatory therapies include inhibitors of NOD-like receptor family, pyrin domain containing 3 inflammasome, of nuclear factor-κB, and of vascular adhesion protein-1, chemokine antagonists, and solithromycin, and approaches targeting common profibrogenic pathways operating in the liver and the kidney include galectin-3 antagonists, and inhibitors of rho-associated protein kinase and of epidermal growth factor activation. The evidence, merits, and limitations of each approach for the treatment of NASH and CKD are discussed. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Molecular mechanism to recruit galectin-3 into multivesicular bodies for polarized exosomal secretion.

PubMed

Bänfer, Sebastian; Schneider, Dominik; Dewes, Jenny; Strauss, Maximilian T; Freibert, Sven-A; Heimerl, Thomas; Maier, Uwe G; Elsässer, Hans-Peter; Jungmann, Ralf; Jacob, Ralf

2018-05-08

The beta-galactoside binding lectin galectin-3 (Gal3) is found intracellularly and in the extracellular space. Secretion of this lectin is mediated independently of the secretory pathway by a not yet defined nonclassical mechanism. Here, we found Gal3 in the lumen of exosomes. Superresolution and electron microscopy studies visualized Gal3 recruitment and sorting into intraluminal vesicles. Exosomal Gal3 release depends on the endosomal sorting complex required for transport I (ESCRT-I) component Tsg101 and functional Vps4a. Either Tsg101 knockdown or expression of dominant-negative Vps4a E228Q causes an intracellular Gal3 accumulation at multivesicular body formation sites. In addition, we identified a highly conserved tetrapeptide P(S/T)AP motif in the amino terminus of Gal3 that mediates a direct interaction with Tsg101. Mutation of the P(S/T)AP motif results in a loss of interaction and a dramatic decrease in exosomal Gal3 secretion. We conclude that Gal3 is a member of endogenous non-ESCRT proteins which are P(S/T)AP tagged for exosomal release.

Pharmacoproteomics of a Metalloproteinase Hydroxamate Inhibitor in Breast Cancer Cells: Dynamics of Membrane Type 1 Matrix Metalloproteinase-Mediated Membrane Protein Shedding ▿ ‡

PubMed Central

Butler, Georgina S.; Dean, Richard A.; Tam, Eric M.; Overall, Christopher M.

2008-01-01

Broad-spectrum matrix metalloproteinase (MMP) inhibitors (MMPI) were unsuccessful in cancer clinical trials, partly due to side effects resulting from limited knowledge of the full repertoire of MMP substrates, termed the substrate degradome, and hence the in vivo functions of MMPs. To gain further insight into the degradome of MMP-14 (membrane type 1 MMP) an MMPI, prinomastat (drug code AG3340), was used to reduce proteolytic processing and ectodomain shedding in human MDA-MB-231 breast cancer cells transfected with MMP-14. We report a quantitative proteomic evaluation of the targets and effects of the inhibitor in this cell-based system. Proteins in cell-conditioned medium (the secretome) and membrane fractions with levels that were modulated by the MMPI were identified by isotope-coded affinity tag (ICAT) labeling and tandem mass spectrometry. Comparisons of the expression of MMP-14 with that of a vector control resulted in increased MMP-14/vector ICAT ratios for many proteins in conditioned medium, indicating MMP-14-mediated ectodomain shedding. Following MMPI treatment, the MMPI/vehicle ICAT ratio was reversed, suggesting that MMP-14-mediated shedding of these proteins was blocked by the inhibitor. The reduction in shedding or the release of substrates from pericellular sites in the presence of the MMPI was frequently accompanied by the accumulation of the protein in the plasma membrane, as indicated by high MMPI/vehicle ICAT ratios. Considered together, this is a strong predictor of biologically relevant substrates cleaved in the cellular context that led to the identification of many undescribed MMP-14 substrates, 20 of which we validated biochemically, including DJ-1, galectin-1, Hsp90α, pentraxin 3, progranulin, Cyr61, peptidyl-prolyl cis-trans isomerase A, and dickkopf-1. Other proteins with altered levels, such as Kunitz-type protease inhibitor 1 and beta-2-microglobulin, were not substrates in biochemical assays, suggesting an indirect affect of the MMPI, which might be important in drug development as biomarkers or, in preclinical phases, to predict systemic drug actions and adverse side effects. Hence, this approach describes the dynamic pattern of cell membrane ectodomain shedding and its perturbation upon metalloproteinase drug treatment. PMID:18505826

Plasma Biomarkers Reflecting Profibrotic Processes in Heart Failure With a Preserved Ejection Fraction

PubMed Central

Zile, Michael R.; Jhund, Pardeep S.; Baicu, Catalin F.; Claggett, Brian L.; Pieske, Burkert; Voors, Adriaan A.; Prescott, Margaret F.; Shi, Victor; Lefkowitz, Martin; McMurray, John J.V.; Solomon, Scott D.

2017-01-01

Background Heart failure with preserved ejection fraction is a clinical syndrome that has been associated with changes in the extracellular matrix. The purpose of this study was to determine whether profibrotic biomarkers accurately reflect the presence and severity of disease and underlying pathophysiology and modify response to therapy in patients with heart failure with preserved ejection fraction. Methods and Results Four biomarkers, soluble form of ST2 (an interleukin-1 receptor family member), galectin-3, matrix metalloproteinase-2, and collagen III N-terminal propeptide were measured in the Prospective Comparison of ARNI With ARB on Management of Heart Failure With Preserved Ejection Fraction (PARAMOUNT) trial at baseline, 12 and 36 weeks after randomization to valsartan or LCZ696. We examined the relationship between baseline biomarkers, demographic and echocardiographic characteristics, change in primary (change in N-terminal pro B-type natriuretic peptide) and secondary (change in left atrial volume) end points. The median (interquartile range) value for soluble form of ST2 (33 [24.6–48.1] ng/mL) and galectin 3 (17.8 [14.1–22.8] ng/mL) were higher, and for matrix metalloproteinase-2 (188 [155.5–230.6] ng/mL) lower, than in previously published referent controls; collagen III N-terminal propeptide (5.6 [4.3–6.9] ng/mL) was similar to referent control values. All 4 biomarkers correlated with severity of disease as indicated by N-terminal pro B-type natriuretic peptide, E/E′, and left atrial volume. Baseline biomarkers did not modify the response to LCZ696 for lowering N-terminal pro B-type natriuretic peptide; however, left atrial volume reduction varied by baseline level of soluble form of ST2 and galectin 3; patients with values less than the observed median (<33 ng/mL soluble form of ST2 and <17.8 ng/mL galectin 3) had reduction in left atrial volume, those above median did not. Although LCZ696 reduced N-terminal pro B-type natriuretic peptide, levels of the other 4 biomarkers were not affected over time. Conclusions In patients with heart failure with preserved ejection fraction, biomarkers that reflect collagen homeostasis correlated with the presence and severity of disease and underlying pathophysiology, and may modify the structural response to treatment. PMID:26754625

Galectin-11 induction in the gastrointestinal tract of cattle following nematode and protozoan infections

USDA-ARS?s Scientific Manuscript database

Galectin-11 (LGALS11) has been suggested to play an important role in protective immunity against gastrointestinal nematodes in ruminants. However, in cattle this molecule has not been characterized in detail. In the current study, it was shown that transcription of LGALS11 was highly inducible in t...

Spinal but not cortical microglia acquire an atypical phenotype with high VEGF, galectin-3 and osteopontin, and blunted inflammatory responses in ALS rats

PubMed Central

Nikodemova, Maria; Small, Alissa L.; Smith, Stephanie M.C.; Mitchell, Gordon S.; Watters, Jyoti J.

2014-01-01

Activation of microglia, CNS resident immune cells, is a pathological hallmark of amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder affecting motor neurons. Despite evidence that microglia contribute to disease progression, the exact role of these cells in ALS pathology remains unknown. We immunomagnetically isolated microglia from different CNS regions of SOD1G93A rats at three different points in disease progression: presymptomatic, symptom onset and end-stage. We observed no differences in microglial number or phenotype in presymptomatic rats compared to wild-type controls. Although after disease onset there was no macrophage infiltration, there were significant increases in microglial numbers in the spinal cord, but not cortex. At disease end-stage, microglia were characterized by high expression of galectin-3, osteopontin and VEGF, and concomitant downregulated expression of TNFα, IL-6, BDNF and arginase-1. Flow cytometry revealed the presence of at least two phenotypically distinct microglial populations in the spinal cord. Immunohistochemistry showed that galectin-3/osteopontin positive microglia were restricted to the ventral horns of the spinal cord, regions with severe motor neuron degeneration. End-stage SOD1G93A microglia from the cortex, a less affected region, displayed similar gene expression profiles to microglia from wild-type rats, and displayed normal responses to systemic inflammation induced by LPS. On the other hand, end-stage SOD1G93A spinal microglia had blunted responses to systemic LPS suggesting that in addition to their phenotypic changes, they may also be functionally impaired. Thus, after disease onset, microglia acquired unique characteristics that do not conform to typical M1 (inflammatory) or M2 (anti-inflammatory) phenotypes. This transformation was observed only in the most affected CNS regions, suggesting that overexpression of mutated hSOD1 is not sufficient to trigger these changes in microglia. These novel observations suggest that microglial regional and phenotypic heterogeneity may be an important consideration when designing new therapeutic strategies targeting microglia and neuroinflammation in ALS. PMID:24269728

Role of PTEN in the Tumor Microenvironment

DTIC Science & Technology

2009-06-01

OS, Boers M, Molthoff CF, van Diest PJ. (2008). Hexokinase III, cyclin A and galectin - 3 are overexpressed in malignant follicular thyroid nodules...2009 2. REPORT TYPE Annual 3 . DATES COVERED (From - To) 4. TITLE AND SUBTITLE Role of PTEN in the Tumor Microenvironment 5a. CONTRACT NUMBER...

Dynamics of Galectin-3 in the Nucleus and Cytoplasm

PubMed Central

Haudek, Kevin C.; Spronk, Kimberly J.; Voss, Patricia G.; Patterson, Ronald J.; Wang, John L.; Arnoys, Eric J.

2009-01-01

This review summarizes selected studies on galectin-3 (Gal3) as an example of the dynamic behavior of a carbohydrate-binding protein in the cytoplasm and nucleus of cells. Within the 15-member galectin family of proteins, Gal3 (Mr ~30,000) is the sole representative of the chimera subclass in which a proline- and glycine-rich NH2-terminal domain is fused onto a COOH-terminal carbohydrate recognition domain responsible for binding galactose-containing glycoconjugates. The protein shuttles between the cytoplasm and nucleus on the basis of targeting signals that are recognized by importin(s) for nuclear localization and exportin-1 (CRM1) for nuclear export. Depending on the cell type, specific experimental conditions in vitro, or tissue location, Gal3 has been reported to be exclusively cytoplasmic, predominantly nuclear, or distributed between the two compartments. The nuclear versus cytoplasmic distribution of the protein must reflect, then, some balance between nuclear import and export, as well as mechanisms of cytoplasmic anchorage or binding to a nuclear component. Indeed, a number of ligands have been reported for Gal3 in the cytoplasm and in the nucleus. Most of the ligands appear to bind Gal3, however, through protein-protein interactions rather than through protein-carbohydrate recognition. In the cytoplasm, for example, Gal3 interacts with the apoptosis repressor Bcl-2 and this interaction may be involved in Gal3’s anti-apoptotic activity. In the nucleus, Gal3 is a required pre-mRNA splicing factor; the protein is incorporated into spliceosomes via its association with the U1 small nuclear ribonucleoprotein (snRNP) complex. Although the majority of these interactions occur via the carbohydrate recognition domain of Gal3 and saccharide ligands such as lactose can perturb some of these interactions, the significance of the protein’s carbohydrate-binding activity, per se, remains a challenge for future investigations. PMID:19616076

Galectin-3 Is Associated with Restrictive Lung Disease and Interstitial Lung Abnormalities.

PubMed

Ho, Jennifer E; Gao, Wei; Levy, Daniel; Santhanakrishnan, Rajalakshmi; Araki, Tetsuro; Rosas, Ivan O; Hatabu, Hiroto; Latourelle, Jeanne C; Nishino, Mizuki; Dupuis, Josée; Washko, George R; O'Connor, George T; Hunninghake, Gary M

2016-07-01

Galectin-3 (Gal-3) has been implicated in the development of pulmonary fibrosis in experimental studies, and Gal-3 levels have been found to be elevated in small studies of human pulmonary fibrosis. We sought to study whether circulating Gal-3 concentrations are elevated early in the course of pulmonary fibrosis. We examined 2,596 Framingham Heart Study participants (mean age, 57 yr; 54% women; 14% current smokers) who underwent Gal-3 assessment using plasma samples and pulmonary function testing between 1995 and 1998. Of this sample, 1,148 underwent subsequent volumetric chest computed tomography. Higher Gal-3 concentrations were associated with lower lung volumes (1.4% decrease in percentage of predicted FEV1 per 1 SD increase in log Gal-3; 95% confidence interval [CI], 0.8-2.0%; P < 0.001; 1.2% decrease in percentage of predicted FVC; 95% CI, 0.6-1.8%; P < 0.001) and decreased diffusing capacity of the lung for carbon monoxide (2.1% decrease; 95% CI, 1.3-2.9%; P < 0.001). These associations remained significant after multivariable adjustment (P ≤ 0.008 for all). Compared with the lowest quartile, participants in the highest Gal-3 quartile were more than twice as likely to have interstitial lung abnormalities visualized by computed tomography (multivariable-adjusted odds ratio, 2.67; 95% CI, 1.49-4.76; P < 0.001). Elevated Gal-3 concentrations are associated with interstitial lung abnormalities coupled with a restrictive pattern, including decreased lung volumes and altered gas exchange. These findings suggest a potential role for Gal-3 in early stages of pulmonary fibrosis.

Galectin-3 Is Associated with Restrictive Lung Disease and Interstitial Lung Abnormalities

PubMed Central

Gao, Wei; Levy, Daniel; Santhanakrishnan, Rajalakshmi; Araki, Tetsuro; Rosas, Ivan O.; Hatabu, Hiroto; Latourelle, Jeanne C.; Nishino, Mizuki; Dupuis, Josée; Washko, George R.; O’Connor, George T.; Hunninghake, Gary M.

2016-01-01

Rationale: Galectin-3 (Gal-3) has been implicated in the development of pulmonary fibrosis in experimental studies, and Gal-3 levels have been found to be elevated in small studies of human pulmonary fibrosis. Objectives: We sought to study whether circulating Gal-3 concentrations are elevated early in the course of pulmonary fibrosis. Methods: We examined 2,596 Framingham Heart Study participants (mean age, 57 yr; 54% women; 14% current smokers) who underwent Gal-3 assessment using plasma samples and pulmonary function testing between 1995 and 1998. Of this sample, 1,148 underwent subsequent volumetric chest computed tomography. Measurements and Main Results: Higher Gal-3 concentrations were associated with lower lung volumes (1.4% decrease in percentage of predicted FEV1 per 1 SD increase in log Gal-3; 95% confidence interval [CI], 0.8–2.0%; P < 0.001; 1.2% decrease in percentage of predicted FVC; 95% CI, 0.6–1.8%; P < 0.001) and decreased diffusing capacity of the lung for carbon monoxide (2.1% decrease; 95% CI, 1.3–2.9%; P < 0.001). These associations remained significant after multivariable adjustment (P ≤ 0.008 for all). Compared with the lowest quartile, participants in the highest Gal-3 quartile were more than twice as likely to have interstitial lung abnormalities visualized by computed tomography (multivariable-adjusted odds ratio, 2.67; 95% CI, 1.49–4.76; P < 0.001). Conclusions: Elevated Gal-3 concentrations are associated with interstitial lung abnormalities coupled with a restrictive pattern, including decreased lung volumes and altered gas exchange. These findings suggest a potential role for Gal-3 in early stages of pulmonary fibrosis. PMID:26771117

Functions of galectins as 'self/non-self'-recognition and effector factors.

PubMed

Vasta, Gerardo R; Feng, Chiguang; González-Montalbán, Nuria; Mancini, Justin; Yang, Lishi; Abernathy, Kelsey; Frost, Graeme; Palm, Cheyenne

2017-07-31

Carbohydrate structures on the cell surface encode complex information that through specific recognition by carbohydrate-binding proteins (lectins) modulates interactions between cells, cells and the extracellular matrix, or mediates recognition of potential microbial pathogens. Galectins are a family of ß-galactoside-binding lectins, which are evolutionary conserved and have been identified in most organisms, from fungi to invertebrates and vertebrates, including mammals. Since their discovery in the 1970s, their biological roles, initially understood as limited to recognition of endogenous carbohydrate ligands in embryogenesis and development, have expanded in recent years by the discovery of their roles in tissue repair and regulation of immune homeostasis. More recently, evidence has accumulated to support the notion that galectins can also bind glycans on the surface of potentially pathogenic microbes, and function as recognition and effector factors in innate immunity, thus establishing a new paradigm. Furthermore, some parasites 'subvert' the recognition roles of the vector/host galectins for successful attachment or invasion. These recent findings have revealed a striking functional diversification in this structurally conserved lectin family. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Protein flexibility and conformational entropy in ligand design targeting the carbohydrate recognition domain of galectin-3.

PubMed

Diehl, Carl; Engström, Olof; Delaine, Tamara; Håkansson, Maria; Genheden, Samuel; Modig, Kristofer; Leffler, Hakon; Ryde, Ulf; Nilsson, Ulf J; Akke, Mikael

2010-10-20

Rational drug design is predicated on knowledge of the three-dimensional structure of the protein-ligand complex and the thermodynamics of ligand binding. Despite the fundamental importance of both enthalpy and entropy in driving ligand binding, the role of conformational entropy is rarely addressed in drug design. In this work, we have probed the conformational entropy and its relative contribution to the free energy of ligand binding to the carbohydrate recognition domain of galectin-3. Using a combination of NMR spectroscopy, isothermal titration calorimetry, and X-ray crystallography, we characterized the binding of three ligands with dissociation constants ranging over 2 orders of magnitude. (15)N and (2)H spin relaxation measurements showed that the protein backbone and side chains respond to ligand binding by increased conformational fluctuations, on average, that differ among the three ligand-bound states. Variability in the response to ligand binding is prominent in the hydrophobic core, where a distal cluster of methyl groups becomes more rigid, whereas methyl groups closer to the binding site become more flexible. The results reveal an intricate interplay between structure and conformational fluctuations in the different complexes that fine-tunes the affinity. The estimated change in conformational entropy is comparable in magnitude to the binding enthalpy, demonstrating that it contributes favorably and significantly to ligand binding. We speculate that the relatively weak inherent protein-carbohydrate interactions and limited hydrophobic effect associated with oligosaccharide binding might have exerted evolutionary pressure on carbohydrate-binding proteins to increase the affinity by means of conformational entropy.

Mineralocorticoid receptor antagonists modulate galectin-3 and interleukin-33/ST2 signaling in left ventricular systolic dysfunction after acute myocardial infarction.

PubMed

Lax, Antonio; Sanchez-Mas, Jesus; Asensio-Lopez, Maria C; Fernandez-Del Palacio, Maria J; Caballero, Luis; Garrido, Iris P; Pastor-Perez, Francisco J; Januzzi, James L; Pascual-Figal, Domingo A

2015-01-01

This study aimed to evaluate the specific role of the 2 available mineralocorticoid receptor antagonists (MRAs), eplerenone and spironolactone, on the modulation of galectin-3 (Gal-3) and interleukin (IL)-33/ST2 signaling in an experimental model of left ventricular systolic dysfunction after acute myocardial infarction (MI). The molecular mechanisms of benefits of MRAs in patients with left ventricular systolic dysfunction after MI not well understood. MI and left ventricular systolic dysfunction were induced by permanent ligation of the anterior coronary artery in 45 male Wistar rats, randomly assigned to no therapy (MI group, n = 15) or to receive MRAs (100 mg/kg/day) for 4 weeks; either eplerenone (n = 15) or spironolactone (n = 15) was used. A sham group was used as a control (n = 8). Elements of the pathway for Gal-3 including transforming growth factor (TGF)-β and SMAD3, as well as that for IL-33/ST2 (including IL-33 and soluble ST2 [sST2]) were analyzed in the infarcted and noninfarcted myocardium by quantitative real-time reverse transcription polymerase chain reaction. Expression of markers of fibrosis (collagen types I and III, tissue inhibitor of metalloproteinase-1) and inflammation (IL-6, tumor necrosis factor-α, monocyte chemotactic protein-1) was also examined. In the infarcted myocardium, compared with sham animals, the MI group had higher concentrations of Gal-3, TGF-β, SMAD3, IL-33, and sST2, as well as higher concentrations of markers of fibrosis and inflammation. Treatment with MRAs down-regulated Gal-3, TGF-β, and SMAD3 and enhanced IL-33/ST2 signaling with lower expression of sST2; protective IL-33 up-regulation was unaffected by MRAs. Modulation of Gal-3 and IL-33/ST2 signaling induced by MRAs correlated with lower expression levels of fibrosis and inflammatory markers. No differences were found between eplerenone and spironolactone. In the noninfarcted myocardium, compared with sham animals, the MI group exhibited a higher expression of Gal-3 and IL-33, but no signs of inflammation or fibrosis were observed; in the presence of MRAs, IL-33 expression was significantly up-regulated, but Gal-3 was unaffected. MRAs play a pivotal role in the Gal-3 and IL-33/ST2 modulation in post-MI cardiac remodeling. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

[Usefulness of galectin-3 expression in the clinical behavior of differentiated thyroid carcinoma].

PubMed

López Mondéjar, Pedro; Picó, Antonio; Seguí, Javier; López Maciá, Alicia

2008-02-16

Our objective was to quantify the galectin-3 (gal-3) expression in differentiated thyroid carcinoma and study its relation with the clinical behavior of these tumors. We investigated the immunohistochemical reaction of gal-3 in patients with papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) and performed a retrospective study in order to find correlations with clinical features. Gal-3 expression was studied in 53 differentiated tyroid carcinomas (42 PTC and 11 FTC), and was related with clinical features: metastases, extrathyroid invasion and initial stage in the diagnosis and persistence disease and relapses in the follow up. Gal-3 expression positivity in PTC had a median of 60% (percentil 25 [p25], 17.5%; percentil 75 [p75], 100%), and was significantly higher (p < 0.0001) than in FTC (median, 0%; p25, 0%; p75, 15%). In PTC, gal-3 expression was significantly higher in advanced stages at the time of initial diagnosis (p = 0.014), persistent disease (p = 0.012) and relapses (p = 0.012) during the follow up. We did not find any significant association between gal-3 expression and clinical features of FTC. Gal-3 is a negative prognosis marker in PTC but not in FTC.

Cis Association of Galectin-9 with Tim-3 Differentially Regulates IL-12/IL-23 Expressions in Monocytes via TLR Signaling

PubMed Central

Ma, Cheng J.; Li, Guang Y.; Cheng, Yong Q.; Wang, Jia M.; Ying, Ruo S.; Shi, Lei; Wu, Xiao Y.; Niki, Toshiro; Hirashima, Mitsumi; Li, Chuan F.; Moorman, Jonathan P.; Yao, Zhi Q.

2013-01-01

Human monocytes/macrophages (M/MФ) of the innate immunity sense and respond to microbial products via specific receptor coupling with stimulatory (such as TLR) and inhibitory (such as Tim-3) receptors. Current models imply that Tim-3 expression on M/MØ can deliver negative signaling to TLR-mediated IL-12 expression through trans association with its ligand Galectin-9 (Gal-9) presented by other cells. However, Gal-9 is also expressed within M/MØ, and the effect of intracellular Gal-9 on Tim-3 activities and inflammatory responses in the same M/MØ remains unknown. In this study, our data suggest that Tim-3 and IL-12/IL-23 gene transcriptions are regulated by enhanced or silenced Gal-9 expression within monocytes through synergizing with TLR signaling. Additionally, TLR activation facilitates Gal-9/Tim-3 cis association within the same M/MØ to differentially regulate IL-12/IL-23 expressions through STAT-3 phosphorylation. These results reveal a ligand (Gal-9) compartment-dependent regulatory effect on receptor (Tim-3) activities and inflammatory responses via TLR pathways—a novel mechanism underlying cellular responses to external or internal cues. PMID:23967307

Characteristic Changes in Decidual Gene Expression Signature in Spontaneous Term Parturition

PubMed Central

El-Azzamy, Haidy; Balogh, Andrea; Romero, Roberto; Xu, Yi; LaJeunesse, Christopher; Plazyo, Olesya; Xu, Zhonghui; Price, Theodore G.; Dong, Zhong; Tarca, Adi L.; Papp, Zoltan; Hassan, Sonia S.; Chaiworapongsa, Tinnakorn; Kim, Chong Jai; Gomez-Lopez, Nardhy; Than, Nandor Gabor

2017-01-01

Background The decidua has been implicated in the “terminal pathway” of human term parturition, which is characterized by the activation of pro-inflammatory pathways in gestational tissues. However, the transcriptomic changes in the decidua leading to terminal pathway activation have not been systematically explored. This study aimed to compare the decidual expression of developmental signaling and inflammation-related genes before and after spontaneous term labor in order to reveal their involvement in this process. Methods Chorioamniotic membranes were obtained from normal pregnant women who delivered at term with spontaneous labor (TIL, n = 14) or without labor (TNL, n = 15). Decidual cells were isolated from snap-frozen chorioamniotic membranes with laser microdissection. The expression of 46 genes involved in decidual development, sex steroid and prostaglandin signaling, as well as pro- and anti-inflammatory pathways, was analyzed using high-throughput quantitative real-time polymerase chain reaction (qRT-PCR). Chorioamniotic membrane sections were immunostained and then semi-quantified for five proteins, and immunoassays for three chemokines were performed on maternal plasma samples. Results The genes with the highest expression in the decidua at term gestation included insulin-like growth factor-binding protein 1 (IGFBP1), galectin-1 (LGALS1), and progestogen-associated endometrial protein (PAEP); the expression of estrogen receptor 1 (ESR1), homeobox A11 (HOXA11), interleukin 1β (IL1B), IL8, progesterone receptor membrane component 2 (PGRMC2), and prostaglandin E synthase (PTGES) was higher in TIL than in TNL cases; the expression of chemokine C-C motif ligand 2 (CCL2), CCL5, LGALS1, LGALS3, and PAEP was lower in TIL than in TNL cases; immunostaining confirmed qRT-PCR data for IL-8, CCL2, galectin-1, galectin-3, and PAEP; and no correlations between the decidual gene expression and the maternal plasma protein concentrations of CCL2, CCL5, and IL-8 were found. Conclusions Our data suggests that with the initiation of parturition, the decidual expression of anti-inflammatory mediators decreases, while the expression of pro-inflammatory mediators and steroid receptors increases. This shift may affect downstream signaling pathways that can lead to parturition. PMID:28226203

Galectin-7 promotes proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting The TGFβ/Smad3 pathway.

PubMed

Luo, Zhenlong; Ji, Yudong; Tian, Dean; Zhang, Yong; Chang, Sheng; Yang, Chao; Zhou, Hongmin; Chen, Zhonghua Klaus

2018-06-08

Galectin-7 (Gal-7) has been associated with cell proliferation and apoptosis. It is known that Gal-7 antagonises TGFβ-mediated effects in hepatocytes by interacting with Smad3. Previously, we have demonstrated that Gal-7 is related to CD4+ T cells responses; nevertheless, its effect and functional mechanism on CD4+ T cells responses remain unclear. The murine CD4+ T cells were respectively cultured with Gal-7, anti-CD3/CD28 mAbs, or with anti-CD3/CD28 mAbs & Gal-7. The effects of Gal-7 on proliferation and the phenotypic changes in CD4+ T cells were assessed by flow cytometry. The cytokines from CD4+ T cells were analysed by quantitative real-time PCR. Subcellular localisation and expression of Smad3 were determined by immunofluorescence staining and Western blot, respectively. Gal-7 enhanced the proliferation of activated CD4+ T cells in a dose- and β-galactoside-dependent manner. Additionally, Gal-7 treatment did not change the ratio of Th2 cells in activated CD4+ T cells, while it increased the ratio of Th1 cells. Gal-7 also induced activated CD4+ T cells to produce a higher level of IFN-γ and TNF-α and a lower level of IL-10. Moreover, Gal-7 treatment significantly accelerated nuclear export of Smad3 in activated CD4+ T cells. These results revealed a novel role of Gal-7 in promoting proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting the TGFβ/Smad3 pathway. Copyright © 2018 Elsevier Ltd. All rights reserved.

Plasma Biomarkers Reflecting Profibrotic Processes in Heart Failure With a Preserved Ejection Fraction: Data From the Prospective Comparison of ARNI With ARB on Management of Heart Failure With Preserved Ejection Fraction Study.

PubMed

Zile, Michael R; Jhund, Pardeep S; Baicu, Catalin F; Claggett, Brian L; Pieske, Burkert; Voors, Adriaan A; Prescott, Margaret F; Shi, Victor; Lefkowitz, Martin; McMurray, John J V; Solomon, Scott D

2016-01-01

Heart failure with preserved ejection fraction is a clinical syndrome that has been associated with changes in the extracellular matrix. The purpose of this study was to determine whether profibrotic biomarkers accurately reflect the presence and severity of disease and underlying pathophysiology and modify response to therapy in patients with heart failure with preserved ejection fraction. Four biomarkers, soluble form of ST2 (an interleukin-1 receptor family member), galectin-3, matrix metalloproteinase-2, and collagen III N-terminal propeptide were measured in the Prospective Comparison of ARNI With ARB on Management of Heart Failure With Preserved Ejection Fraction (PARAMOUNT) trial at baseline, 12 and 36 weeks after randomization to valsartan or LCZ696. We examined the relationship between baseline biomarkers, demographic and echocardiographic characteristics, change in primary (change in N-terminal pro B-type natriuretic peptide) and secondary (change in left atrial volume) end points. The median (interquartile range) value for soluble form of ST2 (33 [24.6-48.1] ng/mL) and galectin 3 (17.8 [14.1-22.8] ng/mL) were higher, and for matrix metalloproteinase-2 (188 [155.5-230.6] ng/mL) lower, than in previously published referent controls; collagen III N-terminal propeptide (5.6 [4.3-6.9] ng/mL) was similar to referent control values. All 4 biomarkers correlated with severity of disease as indicated by N-terminal pro B-type natriuretic peptide, E/E', and left atrial volume. Baseline biomarkers did not modify the response to LCZ696 for lowering N-terminal pro B-type natriuretic peptide; however, left atrial volume reduction varied by baseline level of soluble form of ST2 and galectin 3; patients with values less than the observed median (<33 ng/mL soluble form of ST2 and <17.8 ng/mL galectin 3) had reduction in left atrial volume, those above median did not. Although LCZ696 reduced N-terminal pro B-type natriuretic peptide, levels of the other 4 biomarkers were not affected over time. In patients with heart failure with preserved ejection fraction, biomarkers that reflect collagen homeostasis correlated with the presence and severity of disease and underlying pathophysiology, and may modify the structural response to treatment. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00887588. © 2016 American Heart Association, Inc.

Carbon-1 versus Carbon-3 Linkage of d-Galactose to Porphyrins: Synthesis, Uptake, and Photodynamic Efficiency.

PubMed

Pereira, Patrícia M R; Rizvi, Waqar; Bhupathiraju, N V S Dinesh K; Berisha, Naxhije; Fernandes, Rosa; Tomé, João P C; Drain, Charles Michael

2018-02-21

The use of glycosylated compounds is actively pursued as a therapeutic strategy for cancer due to the overexpression of various types of sugar receptors and transporters on most cancer cells. Conjugation of saccharides to photosensitizers such as porphyrins provides a promising strategy to improve the selectivity and cell uptake of the photosensitizers, enhancing the overall photosensitizing efficacy. Most porphyrin-carbohydrate conjugates are linked via the carbon-1 position of the carbohydrate because this is the most synthetically accessible approach. Previous studies suggest that carbon-1 galactose derivatives show diminished binding since the hydroxyl group in the carbon-1 position of the sugar is a hydrogen bond acceptor in the galectin-1 sugar binding site. We therefore synthesized two isomeric porphyrin-galactose conjugates using click chemistry: one linked via the carbon-1 of the galactose and one linked via carbon-3. Free base and zinc analogs of both conjugates were synthesized. We assessed the uptake and photodynamic therapeutic (PDT) activity of the two conjugates in both monolayer and spheroidal cell cultures of four different cell lines. For both the monolayer and spheroid models, we observe that the uptake of both conjugates is proportional to the protein levels of galectin-1 and the uptake is suppressed after preincubation with an excess of thiogalactose, as measured by fluorescence spectroscopy. Compared to that of the carbon-1 conjugate, the uptake of the carbon-3 conjugate was greater in cell lines containing high expression levels of galectin-1. After photodynamic activation, MTT and lactate dehydrogenase assays demonstrated that the conjugates induce phototoxicity in both monolayers and spheroids of cancer cells.

Thyroid tumors of uncertain malignant potential: morphologic and imunohistochemical analysis of 29 cases.

PubMed

Nechifor-Boila, Adela; Borda, Angela; Sassolas, Geneviève; Hafdi-Nejjari, Zakia; Cătană, Ramona; Borson-Chazot, Françoise; Berger, Nicole; Decaussin-Petrucci, Myriam

2015-04-01

Thyroid tumors of uncertain malignant potential (TT-UMP) include follicular and well-differentiated tumors of UMP (FT-UMP/WDT-UMP), as it refers to the presence of questionable capsular/vascular invasion or incompletely developed papillary thyroid carcinoma (PTC)-type nuclear changes. However, these tumors are difficult to diagnose in most cases. We aimed to investigate whether immunohistochemistry (HBME-1, cytokeratin-19, galectin-3, CD56 and p63) provides additional information concerning such lesions. We performed an immunohistochemical analysis on 29 TT-UMP cases (22 WDTs-UMP and 7 FTs-UMP) selected from the Rhone Alpes thyroid cancer registry and Departement of Pathology, Tîrgu-Mureş Emergency County Hospital database. The clinicopathological and follow-up data were obtained. In the WDT-UMP group, HBME-1 was positive in 9/22 (40.9%) cases. CD56, a marker whose expression is reduced or absent in thyroid carcinoma, showed a "malignant" profile (no expression) in 13/22 (59.1%) cases. 7/22 (31.9%) cases were both HBME-1+ and CD56-. One case showed the co-expression of HBME-1, CD56, galectin-3 and cytokeratin-19. In the FT-UMP group, two cases were positive for HBME-1, other two for both galectin-3 and CK19 and only one case revealed a "malignant" CD56 profile. The follow-up data showed no distant metastases or persistent disease. Our study demonstrated very heterogeneous immunohistochemical profiles for TTs-UMP, further supporting the borderline nature of these lesions. WDTs-UMP revealed a certain tendency toward a PTC profile, suggesting a possible pathogeneticlink between these two entities. However, immunohistochemistry is still to be regarded more as a supporting diagnostic tool, while morphological criteria should always prime in the diagnostic decision. Copyright © 2014 Elsevier GmbH. All rights reserved.

Classical and alternative macrophage activation in the lung following ozone-induced oxidative stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sunil, Vasanthi R., E-mail: sunilva@pharmacy.rutgers.edu; Patel-Vayas, Kinal; Shen, Jianliang

Ozone is a pulmonary irritant known to cause oxidative stress, inflammation and tissue injury. Evidence suggests that macrophages play a role in the pathogenic response; however, their contribution depends on the mediators they encounter in the lung which dictate their function. In these studies we analyzed the effects of ozone-induced oxidative stress on the phenotype of alveolar macrophages (AM). Exposure of rats to ozone (2 ppm, 3 h) resulted in increased expression of 8-hydroxy-2′-deoxyguanosine (8-OHdG), as well as heme oxygenase-1 (HO-1) in AM. Whereas 8-OHdG was maximum at 24 h, expression of HO-1 was biphasic increasing after 3 h andmore » 48–72 h. Cleaved caspase-9 and beclin-1, markers of apoptosis and autophagy, were also induced in AM 24 h post-ozone. This was associated with increased bronchoalveolar lavage protein and cells, as well as matrix metalloproteinase (MMP)-2 and MMP-9, demonstrating alveolar epithelial injury. Ozone intoxication resulted in biphasic activation of the transcription factor, NFκB. This correlated with expression of monocyte chemotactic protein‐1, inducible nitric oxide synthase and cyclooxygenase‐2, markers of proinflammatory macrophages. Increases in arginase-1, Ym1 and galectin-3 positive anti-inflammatory/wound repair macrophages were also observed in the lung after ozone inhalation, beginning at 24 h (arginase-1, Ym1), and persisting for 72 h (galectin-3). This was associated with increased expression of pro-surfactant protein-C, a marker of Type II cell proliferation and activation, important steps in wound repair. These data suggest that both proinflammatory/cytotoxic and anti-inflammatory/wound repair macrophages are activated early in the response to ozone-induced oxidative stress and tissue injury. -- Highlights: ► Lung macrophages are highly sensitive to ozone induced oxidative stress. ► Ozone induces autophagy and apoptosis in lung macrophages. ► Proinflammatory and wound repair macrophages are activated early after ozone. ► Oxidative stress may contribute to regulating macrophage phenotype and function.« less

A combinatorial extracellular matrix platform identifies cell-extracellular matrix interactions that correlate with metastasis

PubMed Central

Reticker-Flynn, Nathan E.; Braga Malta, David F.; Winslow, Monte M.; Lamar, John M.; Xu, Mary J.; Underhill, Gregory H.; Hynes, Richard O.; Jacks, Tyler E.; Bhatia, Sangeeta N.

2013-01-01

Extracellular matrix interactions play essential roles in normal physiology and many pathological processes. While the importance of ECM interactions in metastasis is well documented, systematic approaches to identify their roles in distinct stages of tumorigenesis have not been described. Here we report a novel screening platform capable of measuring phenotypic responses to combinations of ECM molecules. Using a genetic mouse model of lung adenocarcinoma, we measure the ECM-dependent adhesion of tumor-derived cells. Hierarchical clustering of the adhesion profiles differentiates metastatic cell lines from primary tumor lines. Furthermore, we uncovered that metastatic cells selectively associate with fibronectin when in combination with galectin-3, galectin-8, or laminin. We show that these molecules correlate with human disease and that their interactions are mediated in part by α3β1 integrin. Thus, our platform allowed us to interrogate interactions between metastatic cells and their microenvironments, and identified ECM and integrin interactions that could serve as therapeutic targets. PMID:23047680

Galectin-3 Inhibits Galectin-8/Parkin-Mediated Ubiquitination of Group A Streptococcus.

PubMed

Cheng, Yi-Lin; Wu, Yan-Wei; Kuo, Chih-Feng; Lu, Shiou-Ling; Liu, Fu-Tong; Anderson, Robert; Lin, Chiou-Feng; Liu, Yi-Ling; Wang, Wan-Yu; Chen, Ying-Da; Zheng, Po-Xing; Wu, Jiunn-Jong; Lin, Yee-Shin

2017-07-25

Group A streptococcus (GAS) is an important human pathogen that causes a wide variety of cutaneous and systemic infections. Although originally thought to be an extracellular bacterium, numerous studies have demonstrated that GAS can trigger internalization into nonimmune cells to escape from immune surveillance or antibiotic-mediated killing. Epithelial cells possess a defense mechanism involving autophagy-mediated targeting and killing of GAS within lysosome-fused autophagosomes. In endothelial cells, in contrast, we previously showed that autophagy is not sufficient for GAS killing. In the present study, we showed higher galectin-3 (Gal-3) expression and lower Gal-8 expression in endothelial cells than in epithelial cells. The recruitment of Gal-3 to GAS is higher and the recruitment of Gal-8 to GAS is lower in endothelial cells than in epithelial cells. We further showed that Gal-3 promotes GAS replication and diminishes the recruitment of Gal-8 and ubiquitin, the latter of which is a critical protein for autophagy sequestration. After knockdown of Gal-3 in endothelial cells, the colocalization of Gal-8, parkin, and ubiquitin-decorated GAS is significantly increased, as is the interaction of Gal-8 and parkin, an E3 ligase. Furthermore, inhibition of Gal-8 in epithelial cells attenuates recruitment of parkin; both Gal-8 and parkin contribute to ubiquitin recruitment and GAS elimination. Animal studies confirmed that Gal-3-knockout mice develop less-severe skin damage and that GAS replication can be detected only in the air pouch and not in organs and endothelial cells. These results demonstrate that Gal-3 inhibits ubiquitin recruitment by blocking Gal-8 and parkin recruitment, resulting in GAS replication in endothelial cells. IMPORTANCE In epithelial cells, GAS can be efficiently killed within the lysosome-fused autophaosome compartment. However, we previously showed that, in spite of LC-3 recruitment, the autophagic machinery is not sufficient for GAS killing in endothelial cells. In this report, we provide the first evidence that Gal-3, highly expressed in endothelial cells, blocks the tagging of ubiquitin to GAS by inhibiting recruitment of Gal-8 and parkin, leading to an enhancement of GAS replication. We also provide the first demonstration that Gal-8 can interact with parkin, the critical E3 ligase, for resistance to intracellular bacteria by facilitating the decoration of bacteria with ubiquitin chains. Our findings reveal that differential levels of Gal-3 and Gal-8 expression and recruitment to GAS between epithelial cells and endothelial cells may contribute to the different outcomes of GAS elimination or survival and growth of GAS in these two types of cells. Copyright © 2017 Cheng et al.

The α-galactomannan Davanat binds galectin-1 at a site different from the conventional galectin carbohydrate binding domain

PubMed Central

Miller, Michelle C; Klyosov, Anatole; Mayo, Kevin H

2009-01-01

Galectins are a sub-family of lectins, defined by their highly conserved β-sandwich structures and ability to bind to β-galactosides, like Gal β1-4 Glc (lactose). Here, we used 15N-1H HSQC and pulse field gradient (PFG) NMR spectroscopy to demonstrate that galectin-1 (gal-1) binds to the relatively large galactomannan Davanat, whose backbone is composed of β1-4-linked d-mannopyranosyl units to which single d-galactopyranosyl residues are periodically attached via α1-6 linkage (weight-average MW of 59 kDa). The Davanat binding domain covers a relatively large area on the surface of gal-1 that runs across the dimer interface primarily on that side of the protein opposite to the lactose binding site. Our data show that gal-1 binds Davanat with an apparent equilibrium dissociation constant (Kd) of 10 × 10−6 M, compared to 260 × 10−6 M for lactose, and a stiochiometry of about 3 to 6 gal-1 molecules per Davanat molecule. Mannan also interacts at the same galactomannan binding domain on gal-1, but with at least 10-fold lower avidity, supporting the role of galactose units in Davanat for relatively strong binding to gal-1. We also found that the β-galactoside binding domain remains accessible in the gal-1/Davanat complex, as lactose can still bind with no apparent loss in affinity. In addition, gal-1 binding to Davanat also modifies the supermolecular structure of the galactomannan and appears to reduce its hydrodynamic radius and disrupt inter-glycan interactions thereby reducing glycan-mediated solution viscosity. Overall, our findings contribute to understanding gal-1–carbohydrate interactions and provide insight into gal-1 function with potentially significant biological consequences. PMID:19541770

Galectin-3 Performance in Histologic and Cytologic Assessment of Thyroid Nodules: A Systematic Review and Meta-Analysis

PubMed Central

Trimboli, Pierpaolo; Virili, Camilla; Romanelli, Francesco; Crescenzi, Anna; Giovanella, Luca

2017-01-01

The literature on Galectin-3 (Gal-3) was systematically reviewed to achieve more robust information on its histologic reliability in identifying thyroid cancers and on the concordance between Gal-3 test in histologic and cytologic samples. A computer search of the PubMed and Scopus databases was conducted by combinations of the terms thyroid and Gal-3. Initially, 545 articles were found and, after their critical review, 52 original papers were finally included. They reported 8172 nodules with histologic evaluation of Gal-3, of which 358 with also preoperative FNAC Gal-3 assessment. At histology, Gal-3 sensitivity was 87% (95% confidence intervals [CI] from 86% to 88%), and specificity 87% (95% CI from 86% to 88%); in both cases, we found heterogeneity (I2 85% and 93%, respectively) and significant publication bias (p < 0.001). The pooled rate of positive Gal-3 at fine needle aspiration (FNAC) among cancers with histologically proven Gal-3 positivity was 94% (95% CI from 89% to 97%), with neither heterogeneity (I2 14.5%) nor bias (p = 0.086). These data show high reliability of Gal-3 for thyroid cancer at histology, while its sensitivity on FNAC samples is lower. The limits of cytologic preparations and interpretation of Gal-3 results have to be solved. PMID:28800068

Treatment with galectin-1 eye drops regulates mast cell degranulation and attenuates the severity of conjunctivitis.

PubMed

Mello-Bosnic, Claudia; Gimenes, Alexandre Dantas; Oliani, Sonia Maria; Gil, Cristiane Damas

2018-05-31

Galectin-1 (Gal-1) is a β-galactoside-binding protein with diverse biological activities in the pathogenesis of inflammation, however the mechanisms by which Gal-1 modulates cellular responses in allergic inflammatory processes have not been fully determined. In this study, we evaluated the therapeutic potential of Gal-1 eye drops in an experimental model of conjunctivitis. Wistar rats received a topical application of compound (C)48/80 (100 mg/ml) into right eyes and a drop of vehicle into the contralateral eye. Another group of rats received Gal-1 (0.3 or 3 μg/eye) or sodium cromoglycate (SCG; 40 mg/ml) in both eyes and, after 15 min, right eye was challenged with C48/80. Conjunctivitis-induced by C48/80 was characterized by severe eyelid oedema and tearing, but clinical signs were ameliorated by eye drop doses of both Gal-1 (0.3/3 μg) and SCG. As expected, an increased proportion of degranulated mast cells (62%, P < 0.01) and lower histamine levels were observed after 6 h of C48/80 challenge, compared to control (32%). This effect was abrogated by Gal-1 and SCG, which reduced mast cell degranulation (31-36%), eosinophil migration and eosinophil peroxidase levels in the eyes. Gal-1 (3 μg) and SCG treatments also decreased IL-4 levels, as well as activation of mitogen activated protein kinases compared to untreated C48/80 eyes. Our findings suggest that Gal-1 eye drops represent a new therapeutic strategy for ocular allergic inflammation. Copyright © 2018 Elsevier B.V. All rights reserved.

Galectin-3 binding protein links circulating microparticles with electron dense glomerular deposits in lupus nephritis.

PubMed

Nielsen, C T; Østergaard, O; Rekvig, O P; Sturfelt, G; Jacobsen, S; Heegaard, N H H

2015-10-01

A high level of galectin-3-binding protein (G3BP) appears to distinguish circulating cell-derived microparticles in systemic lupus erythematosus (SLE). The aim of this study is to characterize the population of G3BP-positive microparticles from SLE patients compared to healthy controls, explore putative clinical correlates, and examine if G3BP is present in immune complex deposits in kidney biopsies from patients with lupus nephritis. Numbers of annexin V-binding and G3BP-exposing plasma microparticles from 56 SLE patients and 36 healthy controls were determined by flow cytometry. Quantitation of microparticle-associated G3BP, C1q and immunoglobulins was obtained by liquid chromatography tandem mass spectrometry (LC-MS/MS). Correlations between microparticle-G3BP data and clinical parameters were analyzed. Co-localization of G3BP with in vivo-bound IgG was examined in kidney biopsies from one non-SLE control and from patients with class IV (n = 2) and class V (n = 1) lupus nephritis using co-localization immune electron microscopy. Microparticle-G3BP, microparticle-C1q and microparticle-immunoglobulins were significantly (P < 0.01) increased in SLE patients by LC-MS/MS. Three G3BP-exposing microparticle populations could be discerned by flow cytometry, including two subpopulations that were significantly increased in SLE samples (P = 0.01 and P = 0.0002, respectively). No associations of G3BP-positive microparticles with clinical manifestations or disease activity were found. Immune electron microscopy showed co-localization of G3BP with in vivo-bound IgG in glomerular electron dense immune complex deposits in all lupus nephritis biopsies. Both circulating microparticle-G3BP numbers as well as G3BP expression are increased in SLE patients corroborating G3BP being a feature of SLE microparticles. By demonstrating G3BP co-localized with deposited immune complexes in lupus nephritis, the study supports cell-derived microparticles as a major autoantigen source and provides a new understanding of the origin of immune complexes occurring in lupus nephritis. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Galectin-9 ameliorates anti-GBM glomerulonephritis by inhibiting Th1 and Th17 immune responses in mice.

PubMed

Zhang, Qian; Luan, Hong; Wang, Le; He, Fan; Zhou, Huan; Xu, Xiaoli; Li, Xingai; Xu, Qing; Niki, Toshiro; Hirashima, Mitsuomi; Xu, Gang; Lv, Yongman; Yuan, Jin

2014-04-15

Antiglomerular basement membrane glomerulonephritis (anti-GBM GN) is a Th1- and Th17-predominant autoimmune disease. Galectin-9 (Gal-9), identified as the ligand of Tim-3, functions in diverse biological processes and leads to the apoptosis of CD4(+)Tim-3(+) T cells. It is still unclear how Gal-9 regulates the functions of Th1 and Th17 cells and prevents renal injury in anti-GBM GN. In this study, Gal-9 was administered to anti-GBM GN mice for 7 days. We found that Gal-9 retarded the increase of Scr, ameliorated renal tubular injury, and reduced the formation of crescents. The infiltration of Th1 and Th17 cells into the spleen and kidneys significantly decreased in Gal-9-treated nephritic mice. The reduced infiltration of Th1 and Th17 cells might be associated with the downregulation of CCL-20, CXCL-9, and CXCL-10 mRNAs in the kidney. In parallel, the blood levels of IFN-γ and IL-17A declined in Gal-9-treated nephritic mice at days 21 and 28. In addition, an enhanced Th2 cell-mediated immune response was observed in the kidneys of nephritic mice after a 7-day injection of Gal-9. In conclusion, the protective role of Gal-9 in anti-GBM GN is associated with the inhibition of Th1 and Th17 cell-mediated immune responses and enhanced Th2 immunity in the kidney.

Glycobiology of ocular angiogenesis

PubMed Central

Markowska, Anna I; Cao, Zhiyi; Panjwani, Noorjahan

2014-01-01

Ocular neovascularization can affect almost all the tissues of the eye: the cornea, the iris, the retina, and the choroid. Pathological neovascularization is the underlying cause of vision loss in common ocular conditions such as diabetic retinopathy, retinopathy of prematurity and age-related macular neovascularization. Glycosylation is the most common covalent posttranslational modification of proteins in mammalian cells. A growing body of evidence demonstrates that glycosylation influences the process of angiogenesis and impacts activation, proliferation, and migration of endothelial cells as well as the interaction of angiogenic endothelial cells with other cell types necessary to form blood vessels. Recent studies have provided evidence that members of the galectin class of β-galactoside-binding proteins modulate angiogenesis by novel carbohydrate-based recognition systems involving interactions between glycans of angiogenic cell surface receptors and galectins. This review discusses the significance of glycosylation and the role of galectins in the pathogenesis of ocular neovascularization. PMID:25108228

Specific intermolecular interactions of conserved water molecules with amino acids in the Galectin-1 carbohydrate recognition domain

NASA Astrophysics Data System (ADS)

Di Lella, Santiago; Petruk, Ariel A.; Armiño, Diego J. Alonso de; Álvarez, Rosa M. S.

2010-08-01

Water molecules, rigidly associated to protein surfaces, play a key role in stabilizing biomolecules and participating in their biological functions. Recent studies on the solvation properties of the carbohydrate recognition domain of Galectin-1 by means of molecular dynamic simulations have revealed the existence of several water sites which were well correlated to both the bound water molecules observed in the crystal structure of the protein in the free state and to some of the hydroxyl groups of the carbohydrate ligand observed in the crystal structure of the complexed protein. In this work, we present a study using quantum mechanical methods (B3LYP/6-311++G(3df,3dp)//B3LYP/6-31+G(d)) to determine the energy involved in the binding of these water molecules to specific amino acids in the carbohydrate recognition domain of the protein. By modeling the hydroxyl groups of the carbohydrate by methanol, the energies associated to the local interactions between the ligand and the protein have been evaluated by replacing specific water molecules with methanol. The values of the binding energies have been compared to those previously obtained by the molecular dynamic method.

Crystal structure of mouse coronavirus receptor-binding domain complexed with its murine receptor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, Guiqing; Sun, Dawei; Rajashankar, Kanagalaghatta R.

2011-09-28

Coronaviruses have evolved diverse mechanisms to recognize different receptors for their cross-species transmission and host-range expansion. Mouse hepatitis coronavirus (MHV) uses the N-terminal domain (NTD) of its spike protein as its receptor-binding domain. Here we present the crystal structure of MHV NTD complexed with its receptor murine carcinoembryonic antigen-related cell adhesion molecule 1a (mCEACAM1a). Unexpectedly, MHV NTD contains a core structure that has the same {beta}-sandwich fold as human galectins (S-lectins) and additional structural motifs that bind to the N-terminal Ig-like domain of mCEACAM1a. Despite its galectin fold, MHV NTD does not bind sugars, but instead binds mCEACAM1a through exclusivemore » protein-protein interactions. Critical contacts at the interface have been confirmed by mutagenesis, providing a structural basis for viral and host specificities of coronavirus/CEACAM1 interactions. Sugar-binding assays reveal that galectin-like NTDs of some coronaviruses such as human coronavirus OC43 and bovine coronavirus bind sugars. Structural analysis and mutagenesis localize the sugar-binding site in coronavirus NTDs to be above the {beta}-sandwich core. We propose that coronavirus NTDs originated from a host galectin and retained sugar-binding functions in some contemporary coronaviruses, but evolved new structural features in MHV for mCEACAM1a binding.« less

Galectin-3 in autoimmunity and autoimmune diseases

PubMed Central

de Oliveira, Felipe L; Gatto, Mariele; Bassi, Nicola; Luisetto, Roberto; Ghirardello, Anna; Punzi, Leonardo

2015-01-01

Galectin-3 (gal-3) is a β-galactoside-binding lectin, which regulates cell–cell and extracellular interactions during self/non-self-antigen recognition and cellular activation, proliferation, differentiation, migration and apoptosis. It plays a significant role in cellular and tissue pathophysiology by organizing niches that drive inflammation and immune responses. Gal-3 has some therapeutic potential in several diseases, including chronic inflammatory disorders, cancer and autoimmune diseases. Gal-3 exerts a broad spectrum of functions which differs according to its intra- or extracellular localization. Recombinant gal-3 strategy has been used to identify potential mode of action of gal-3; however, exogenous gal-3 may not reproduce the functions of the endogenous gal-3. Notably, gal-3 induces monocyte–macrophage differentiation, interferes with dendritic cell fate decision, regulates apoptosis on T lymphocytes and inhibits B-lymphocyte differentiation into immunoglobulin secreting plasma cells. Considering the influence of these cell populations in the pathogenesis of several autoimmune diseases, gal-3 seems to play a role in development of autoimmunity. Gal-3 has been suggested as a potential therapeutic agent in patients affected with some autoimmune disorders. However, the precise role of gal-3 in driving the inflammatory process in autoimmune or immune-mediated disorders remains elusive. Here, we reviewed the involvement of gal-3 in cellular and tissue events during autoimmune and immune-mediated inflammatory diseases. PMID:26142116

PD-L1, Galectin-9 and CD8+ tumor-infiltrating lymphocytes are associated with survival in hepatocellular carcinoma.

PubMed

Sideras, Kostandinos; Biermann, Katharina; Verheij, Joanne; Takkenberg, Bart R; Mancham, Shanta; Hansen, Bettina E; Schutz, Hannah M; de Man, Robert A; Sprengers, Dave; Buschow, Sonja I; Verseput, Maddy C M; Boor, Patrick P C; Pan, Qiuwei; van Gulik, Thomas M; Terkivatan, Turkan; Ijzermans, Jan N M; Beuers, Ulrich H W; Sleijfer, Stefan; Bruno, Marco J; Kwekkeboom, Jaap

2017-01-01

Novel systemic treatments for hepatocellular carcinoma (HCC) are strongly needed. Immunotherapy is a promising strategy that can induce specific antitumor immune responses. Understanding the mechanisms of immune resistance by HCC is crucial for development of suitable immunotherapeutics. We used immunohistochemistry on tissue-microarrays to examine the co-expression of the immune inhibiting molecules PD-L1, Galectin-9, HVEM and IDO, as well as tumor CD8 + lymphocyte infiltration in HCC, in two independent cohorts of patients. We found that at least some expression in tumor cells was seen in 97% of cases for HVEM, 83% for PD-L1, 79% for Gal-9 and 66% for IDO. In the discovery cohort (n = 94), we found that lack of, or low, tumor expression of PD-L1 ( p < 0.001), Galectin-9 ( p < 0.001) and HVEM ( p < 0.001), and low CD8 + TIL count ( p = 0.016), were associated with poor HCC-specific survival. PD-L1, Galectin-9 and CD8 + TIL count were predictive of HCC-specific survival independent of baseline clinicopathologic characteristics and the combination of these markers was a powerful predictor of HCC-specific survival (HR 0.29; p <0.001). These results were confirmed in the validation cohort (n = 60). We show that low expression levels of PD-L1 and Gal-9 in combination with low CD8 + TIL count predict extremely poor HCC-specific survival and it requires a change in two of these parameters to significantly improve prognosis. In conclusion, intra-tumoral expression of these immune inhibiting molecules was observed in the majority of HCC patients. Low expression of PD-L1 and Galectin-9 and low CD8 + TIL count are associated with poor HCC-specific survival. Combining immune biomarkers leads to superior predictors of HCC mortality.

Decellularized Matrix from Tumorigenic Human Mesenchymal Stem Cells Promotes Neovascularization with Galectin-1 Dependent Endothelial Interaction

PubMed Central

Burns, Jorge S.; Kristiansen, Malthe; Kristensen, Lars P.; Larsen, Kenneth H.; Nielsen, Maria O.; Christiansen, Helle; Nehlin, Jan; Andersen, Jens S.; Kassem, Moustapha

2011-01-01

Background Acquisition of a blood supply is fundamental for extensive tumor growth. We recently described vascular heterogeneity in tumours derived from cell clones of a human mesenchymal stem cell (hMSC) strain (hMSC-TERT20) immortalized by retroviral vector mediated human telomerase (hTERT) gene expression. Histological analysis showed that cells of the most vascularized tumorigenic clone, -BD11 had a pericyte-like alpha smooth muscle actin (ASMA+) and CD146+ positive phenotype. Upon serum withdrawal in culture, -BD11 cells formed cord-like structures mimicking capillary morphogenesis. In contrast, cells of the poorly tumorigenic clone, -BC8 did not stain for ASMA, tumours were less vascularized and serum withdrawal in culture led to cell death. By exploring the heterogeneity in hMSC-TERT20 clones we aimed to understand molecular mechanisms by which mesenchymal stem cells may promote neovascularization. Methodology/Principal Findings Quantitative qRT-PCR analysis revealed similar mRNA levels for genes encoding the angiogenic cytokines VEGF and Angiopoietin-1 in both clones. However, clone-BD11 produced a denser extracellular matrix that supported stable ex vivo capillary morphogenesis of human endothelial cells and promoted in vivo neovascularization. Proteomic characterization of the -BD11 decellularized matrix identified 50 extracellular angiogenic proteins, including galectin-1. siRNA knock down of galectin-1 expression abrogated the ex vivo interaction between decellularized -BD11 matrix and endothelial cells. More stable shRNA knock down of galectin-1 expression did not prevent -BD11 tumorigenesis, but greatly reduced endothelial migration into -BD11 cell xenografts. Conclusions Decellularized hMSC matrix had significant angiogenic potential with at least 50 angiogenic cell surface and extracellular proteins, implicated in attracting endothelial cells, their adhesion and activation to form tubular structures. hMSC -BD11 surface galectin-1 expression was required to bring about matrix-endothelial interactions and for xenografted hMSC -BD11 cells to optimally recruit host vasculature. PMID:21779348

Role of PTEN in the Tumor Microenvironment

DTIC Science & Technology

2008-06-01

van Diest PJ. (2008). Hexokinase III, cyclin A and galectin - 3 are overexpressed in malignant follicular thyroid nodules. Clin Endocrinol (Oxf) 2...Annual 3 . DATES COVERED (From - To) 15 May 2007 – 14 May 2008 4. TITLE AND SUBTITLE Role of PTEN in the Tumor Microenvironment 5a. CONTRACT NUMBER...1998) that impacts several signaling pathways, including phosphoinositide 3 -kinase (PI3K), and Ras-MAPK-Erk1/2 signaling pathways. Pten inactivation

Glycosylation-dependent galectin-receptor interactions promote Chlamydia trachomatis infection.

PubMed

Lujan, Agustin L; Croci, Diego O; Gambarte Tudela, Julián A; Losinno, Antonella D; Cagnoni, Alejandro J; Mariño, Karina V; Damiani, María T; Rabinovich, Gabriel A

2018-06-11

Chlamydia trachomatis ( Ct ) constitutes the most prevalent sexually transmitted bacterium worldwide. Chlamydial infections can lead to severe clinical sequelae including pelvic inflammatory disease, ectopic pregnancy, and tubal infertility. As an obligate intracellular pathogen, Ct has evolved multiple strategies to promote adhesion and invasion of host cells, including those involving both bacterial and host glycans. Here, we show that galectin-1 (Gal1), an endogenous lectin widely expressed in female and male genital tracts, promotes Ct infection. Through glycosylation-dependent mechanisms involving recognition of bacterial glycoproteins and N -glycosylated host cell receptors, Gal1 enhanced Ct attachment to cervical epithelial cells. Exposure to Gal1, mainly in its dimeric form, facilitated bacterial entry and increased the number of infected cells by favoring Ct - Ct and Ct -host cell interactions. These effects were substantiated in vivo in mice lacking Gal1 or complex β1-6-branched N -glycans. Thus, disrupting Gal1- N -glycan interactions may limit the severity of chlamydial infection by inhibiting bacterial invasion of host cells.

Two-marker combinations for preoperative discrimination of benign and malignant ovarian masses.

PubMed

Freydanck, Maj Kristin; Laubender, Ruediger Paul; Rack, Brigitte; Schuhmacher, Lan; Jeschke, Udo; Scholz, Christoph

2012-05-01

When caring for patients with ovarian neoplasms, correct preoperative discrimination of benign and malignant disease is deemed vital. In this study, we tested serum biomarkers' alone and in combination, to achieve this aim. We measured the concentrations of Cancer Antigen (CA)-125, CA15-3, CA27-29, Carcinoembryonic Antigen (CEA), CA19-9, human chorionic gonadotropin (hCG), Placental Protein (PP)1490, CA72-4, galectin-3, galectin-1 and Human epididymis protein (HE)4 in sera of 133 patients with pelvic masses by ELISA and correlated the results to subsequent histology. We used the area under the curve (AUC) of biomarkers and their combinations and calculated the 95% confidence intervals by using casewise resampling. The best single biomarkers were CA-125 (sensitivity and AUC) and HE4 (specificity). Combinations with HE4 and CA19-9 improved the predictive power of CA-125. The best discrimination was achieved by the combination of CA-125 and HE4, with an AUC of 0.961. A combination of CA-125 with HE4 could facilitate the identification of women at risk for ovarian cancer.

Prospective Validation of a Screening Biomarker Approach Combining Amino-Terminal Pro-Brain Natriuretic Peptide With Galectin-3 Predicts Death and Cardiovascular Events in Asymptomatic Hemodialysis Patients.

PubMed

Voroneanu, Luminita; Siriopol, Dimitrie; Apetrii, Mugurel; Hogas, Simona; Onofriescu, Mihai; Nistor, Ionut; Kanbay, Mehmet; Dumea, Raluca; Cusai, Silvia; Cianga, Petru; Constantinescu, Daniela; Covic, Adrian

2018-05-01

Cardiovascular (CV) disease is a major cause of death in hemodialysis patients. Biomarkers used to identify high-risk asymptomatic patients would allow early evaluation of cardiac dysfunction and appropriate therapeutic intervention. Amino-terminal pro-brain natriuretic peptide (NT-proBNP) and galectin-3 (Gal-3) may serve this purpose. Plasma levels of NT-proBNP and Gal-3 were measured in 173 patients. Patients were prospectively followed for occurrences of major CV events or death. The association of NT-proBNP and Gal-3 with outcome was analyzed. The prognostic abilities for the combined outcome of Gal-3 and/or NT-proBNP were evaluated. During a median follow-up of 36 months, there were 47 incident outcomes (death and CV events). In the univariable Cox analysis, age, hypertension, albumin, phosphorus levels, and combined elevation of NT-proBNP with Gal-3 above the median (hazard ratio [HR] = 3.65, 95% confidence interval [CI] = 1.45-9.21) were associated with outcomes. In multivariable Cox analysis, both NT-proBNP and Gal-3 values above the median remained associated with outcomes (HR = 3.34, 95% CI = 1.30-8.56). In clinically asymptomatic dialysis patients, combined use of NT-proBNP and Gal-3 may improve risk stratification for death and CV events.

Galectin 3 for the diagnosis of bladder cancer

PubMed Central

El Gendy, Hoda; Madkour, Bothina; Abdelaty, Sara; Essawy, Fayza; Khattab, Dina; Hammam, Olfat; El Kholy, Amr; Nour, Hani H.

2013-01-01

Objective To evaluate serum levels of galectin-3 (G-3) in patients with bladder cancer and a control group, as a potential diagnostic and prognostic serum tumour marker. Patients and methods Between November 2012 and January 2013, 55 patients (median age 58 years) were enrolled into three groups, i.e., a control, those with transitional cell carcinoma (TCC) or those with squamous cell carcinoma (SCC). The serum G-3 level was measured the night before cystoscopy. The levels of G-3 levels were correlated with tumour type, stage and grade, and in relation to levels in normal urothelium. The results were analysed statistically using the Mann–Whitney U-test, the Kruskal–Wallis test and the receiver operating characteristic curve, as appropriate. Results The median serum G-3 level was 100, 720 and 920 pg/mL in the control, TCC and SCC groups, respectively, with very significantly greater G-3 levels in both the TCC and SCC groups than in the control group. Patients with high-grade TCC had a statistically significantly greater serum G-3 level than those with low-grade tumours, as did those with muscle-invasive TCC than those with Ta tumours. Conclusions The level of G-3 can aid as a diagnostic marker in patients with either TCC or SCC of the bladder, but the prognostic significance of G-3 remains to be confirmed. PMID:26019945

Molecular characterization of a novel proto-type antimicrobial protein galectin-1 from striped murrel.

PubMed

Arasu, Abirami; Kumaresan, Venkatesh; Sathyamoorthi, Akila; Chaurasia, Mukesh Kumar; Bhatt, Prasanth; Gnanam, Annie J; Palanisamy, Rajesh; Marimuthu, Kasi; Pasupuleti, Mukesh; Arockiaraj, Jesu

2014-11-01

In this study, we reported a molecular characterization of a novel proto-type galectin-1 from the striped murrel Channa striatus (named as CsGal-1). The full length CsGal-1 was identified from an established striped murrel cDNA library and further we confirmed the sequence by cloning. The complete cDNA sequence of CsGal-1 is 590 base pairs (bp) in length and its coding region encoded a poly peptide of 135 amino acids. The polypeptide contains a galactoside binding lectin domain at 4-135. The domain carries a sugar binding site at 45-74 along with its signatures (H(45)-X-Asn(47)-X-Arg(49) and Trp(69)-X-X-Glu(72)-X-Arg(74)). CsGal-1 shares a highly conserved carbohydrate recognition domain (CRD) with galectin-1 from other proto-type galectin of teleosts. The mRNA expressions of CsGal-1 in healthy and various immune stimulants including Aphanomyces invadans, Aeromonas hydrophila, Escherchia coli lipopolysaccharide and poly I:C injected tissues of C. striatus were examined using qRT-PCR. CsGal-1 mRNA is highly expressed in kidney and is up-regulated with different immune stimulants at various time points. To understand its biological activity, the coding region of CsGal-1 gene was expressed in an E. coli BL21 (DE3) cloning system and its recombinant protein was purified. The recombinant CsGal-1 protein was agglutinated with mouse erythrocytes at a concentration of 4μg/mL in a calcium independent manner. CsGal-1 activity was inhibited by d-galactose at 25mM(-1) and d-glucose and d-fructose at 100mM(-1). The results of microbial binding assay showed that the recombinant CsGal-1 protein agglutinated only with the Gram-negative bacteria. Interestingly, we observed no agglutination against Gram-positive bacteria. Overall, the study showed that CsGal-1 is an important immune gene involved in the recognition and elimination of pathogens in C. striatus. Copyright © 2014 Elsevier GmbH. All rights reserved.

Decreased expression of RNA interference machinery, Dicer and Drosha, is associated with poor outcome in ovarian cancer patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Merritt, William M.; Lin, Yvonne G.; Han, Liz Y.

2008-05-06

The clinical and functional significance of RNA interference (RNAi) machinery, Dicer and Drosha, in ovarian cancer is not known and was examined. Dicer and Drosha expression was measured in ovarian cancer cell lines (n=8) and invasive epithelial ovarian cancer specimens (n=111) and correlated with clinical outcome. Validation was performed with previously published cohorts of ovarian, breast, and lung cancer patients. Anti-Galectin-3 siRNA and shRNA transfections were used for in vitro functional studies. Dicer and Drosha mRNA and protein levels were decreased in 37% to 63% of ovarian cancer cell lines and in 60% and 51% of human ovarian cancer specimens,more » respectively. Low Dicer was significantly associated with advanced tumor stage (p=0.007), and low Drosha with suboptimal surgical cytoreduction (p=0.02). Tumors with both high Dicer and Drosha were associated with increased median patient survival (>11 years vs. 2.66 years for other groups; p<0.001). In multivariate analysis, high Dicer (HR=0.48; p=0.02), high-grade histology (HR=2.46; p=0.03), and poor chemoresponse (HR=3.95; p<0.001) were identified as independent predictors of disease-specific survival. Findings of poor clinical outcome with low Dicer expression were validated in separate cohorts of cancer patients. Galectin-3 silencing with siRNA transfection was superior to shRNA in cell lines with low Dicer (78-95% vs. 4-8% compared to non-targeting sequences), and similar in cell lines with high Dicer. Our findings demonstrate the clinical and functional impact of RNAi machinery alterations in ovarian carcinoma and support the use of siRNA constructs that do not require endogenous Dicer and Drosha for therapeutic applications.« less

The N- and C-terminal carbohydrate recognition domains of Haemonchus contortus galectin bind to distinct receptors of goat PBMC and contribute differently to its immunomodulatory functions in host-parasite interactions.

PubMed

Lu, MingMin; Tian, XiaoWei; Yang, XinChao; Yuan, Cheng; Ehsan, Muhammad; Liu, XinChao; Yan, RuoFeng; Xu, LiXin; Song, XiaoKai; Li, XiangRui

2017-09-05

Hco-gal-m is a tandem-repeat galectin isolated from the adult worm of Haemonchus contortus. A growing body of studies have demonstrated that Hco-gal-m could exert its immunomodulatory effects on host peripheral blood mononuclear cells (PBMC) to facilitate the immune evasion. Our previous work revealed that C-terminal and N-terminal carbohydrate recognition domains (CRD) of Hco-gal-m had different sugar binding abilities. However, whether different domains of Hco-gal-m account differently for its multiple immunomodulatory functions in the host-parasite interaction remains to be elucidated. We found that the N-terminal CRD of Hco-gal-m (MNh) and the C-terminal CRD (MCh) could bind to goat peripheral blood mononuclear cells by distinct receptors: transmembrane protein 63A (TMEM63A) was a binding receptor of MNh, while transmembrane protein 147 (TMEM147) was a binding receptor of MCh. In addition, MCh was much more potent than MNh in inhibiting cell proliferation and inducing apoptosis, while MNh was much more effective in inhibiting NO production. Moreover, MNh could suppress the transcription of interferon-γ (IFN-γ), but MCh not. Our data suggested that these two CRDs of Hco-gal-m bind to distinct receptors and contributed differently to its ability to downregulate host immune response. These results will improve our understanding of galectins from parasitic nematodes contributing to the mechanism of parasitic immune evasion and continue to illustrate the diverse range of biological activities attributable to the galectin family.

Impact of human galectin-1 binding to saccharide ligands on dimer dissociation kinetics and structure.

PubMed

Romero, Juan M; Trujillo, Madia; Estrin, Darío A; Rabinovich, Gabriel A; Di Lella, Santiago

2016-12-01

Endogenous lectins can control critical biological responses, including cell communication, signaling, angiogenesis and immunity by decoding glycan-containing information on a variety of cellular receptors and the extracellular matrix. Galectin-1 (Gal-1), a prototype member of the galectin family, displays only one carbohydrate recognition domain and occurs in a subtle homodimerization equilibrium at physiologic concentrations. Such equilibrium critically governs the function of this lectin signaling by allowing tunable interactions with a preferential set of glycosylated receptors. Here, we used a combination of experimental and computational approaches to analyze the kinetics and mechanisms connecting Gal-1 ligand unbinding and dimer dissociation processes. Kinetic constants of both processes were found to differ by an order of magnitude. By means of steered molecular dynamics simulations, the ligand unbinding process was followed monitoring water occupancy changes. By determining the water sites in a carbohydrate binding place during the unbinding process, we found that rupture of ligand-protein interactions induces an increase in energy barrier while ligand unbinding process takes place, whereas the entry of water molecules to the binding groove and further occupation of their corresponding water sites contributes to lowering of the energy barrier. Moreover, our findings suggested local asymmetries between the two subunits in the dimer structure detected at a nanosecond timescale. Thus, integration of experimental and computational data allowed a more complete understanding of lectin ligand binding and dimerization processes, suggesting new insights into the relationship between Gal-1 structure and function and renewing the discussion on the biophysics and biochemistry of lectin-ligand lattices. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Ligand-free method to produce the anti-angiogenic recombinant Galectin-3 carbohydrate recognition domain.

PubMed

Wiecikowski, Adalgisa; Cabral, Katia Maria Dos Santos; Almeida, Marcius da Silva; Carvalho, Renato Sampaio

2018-04-01

Galectin-3 (Gal3) is involved in many physiological processes related to tumor growth, such as promoting angiogenesis, cell migration/invasion, resistance to apoptosis and immune response modulation. Usually the overexpression of Gal3 is a poor prognostic marker for cancer patients. Recombinant Gal3 carbohydrate domain (Gal3C) has been proposed as a useful tool to inhibit angiogenesis. So far, all production protocols reported for Gal3C production have used proteolytic cleavage of full length Gal3 and/or affinity-based purification. This involves dialysis, a time consuming step used to eliminate the elution ligand, usually lactose. In this report, we describe an alternative method to produce human recombinant Gal3C in E. coli, purified with cationic exchange and size exclusion chromatography. The recombinant protein was characterized using circular dichroism and nuclear magnetic resonance, showing a beta sheet enriched well-folded globular structure. The average yield obtained was 26 mg/L of broth and the purity was above 99%. The anti-angiogenic activity was assessed in vitro and showed a reduction of 70% and 77% in endothelial cells tubule formation upon treatment with 10 and 20 μg/mL, respectively and also had no impact on cell viability. The method described here is more suitable for both laboratory and industrial production of the potential anti-tumor Gal3C. Copyright © 2017 Elsevier Inc. All rights reserved.

Dectin-1 Activation on Macrophages by Galectin-9 Promotes Pancreatic Carcinoma and Peritumoral Immune-Tolerance

PubMed Central

Daley, Donnele; Mani, Vishnu R.; Mohan, Navyatha; Akkad, Neha; Ochi, Atsuo; Heindel, Daniel W.; Lee, Ki Buom; Zambirinis, Constantinos P.; Pandian, Gautam S.D. Balasubramania; Savadkar, Shivraj; Torres-Hernandez, Alejandro; Nayak, Shruti; Wang, Ding; Hundeyin, Mautin; Diskin, Brian; Aykut, Berk; Werba, Gregor; Barilla, Rocky M.; Rodriguez, Robert; Chang, Steven; Gardner, Lawrence; Mahal, Lara K.; Ueberheide, Beatrix; Miller, George

2017-01-01

The progression of pancreatic oncogenesis requires immune-suppressive inflammation in cooperation with oncogenic mutations. However, the drivers of intra-tumoral immune tolerance are uncertain. Dectin-1 is an innate immune receptor critical in anti-fungal immunity, but its role in sterile inflammation and oncogenesis is not well-defined. Further, non-pathogen-derived ligands for Dectin-1 have not been characterized. We found that Dectin-1 is highly expressed on macrophages in pancreatic ductal adenocarcinoma (PDA). Dectin-1 ligation accelerated PDA, whereas Dectin-1 deletion or blockade of its downstream signaling was protective. We found that Dectin-1 ligates the lectin Galectin-9 in the PDA tumor microenvironment resulting in tolerogenic macrophage programming and adaptive immune suppression. Upon interruption of the Dectin-1–Galectin-9 axis, CD4+ and CD8+ T cells – which are dispensable to PDA progression in hosts with an intact signaling axis – become reprogrammed into indispensable mediators of anti-tumor immunity. These data suggest that targeting Dectin-1 signaling is an attractive strategy for the immunotherapy of PDA. PMID:28394331

Importance of nuclear localization for the apoptosis-induced activity of a fungal galectin AAL (Agrocybe aegerita lectin)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liang, Yi; Feng, Lei; Tong, Xin

2009-08-28

Agrocybe aegerita lectin (AAL) was identified previously in our group as a novel galectin from medicinal fungi Agrocybe aegerita, and has been shown to effectively induce cancer cell cycle arrest and apoptosis in vitro and tumor regression in vivo. Here, AAL was observed to translocate into the HeLa cell nucleus and induce cell apoptosis when it was predominantly in the nucleus. The N-terminus and C-terminus of AAL were required for nuclear localization. Site mutated proteins were generated based on AAL structure. Dimer interface mutant I25G, carbohydrate recognition domain (CRD) mutant R63H, and loop region mutant L33A could not enter themore » nucleus and lost the ability to induce apoptosis. CRD mutant H59Q and loop region mutant I144G maintained nuclear localization activity, and H59Q retained residual bioability but I144G had no activity, indicating that nuclear localization is important but not sufficient for AAL to become apoptotically active. Our findings provide a novel antitumor mechanism of fungal galectin.« less

Interaction between Galectin-9/TIM-3 pathway and follicular helper CD4+ T cells contributes to viral persistence in chronic hepatitis C.

PubMed

Zhuo, Ya; Zhang, Yi-Fu; Wu, Hong-Jie; Qin, Lei; Wang, Yan-Ping; Liu, A-Min; Wang, Xin-Hong

2017-10-01

Both Galectin 9 (Gal-9)/T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) pathway and follicular helper CD4 + T (Tfh) cells play important roles in persistent hepatitis C virus (HCV) infection. Thus, we aimed to investigate the regulatory role of interaction between Gal-9/TIM-3 pathway and Tfh cells in chronic hepatitis C. A total of 44 chronic hepatitis C patients and 19 normal controls (NCs) were enrolled in this study. Purified CD4 + T cells were cultured by TIM-3 Fc protein, recombinant Gal-9, or IL-21 for 48h. TIM-3 expression, Tfh proportion, and IL-21 production was measured, respectively. The immunomodulatory role of Gal-9/TIM-3 and IL-21 was also investigated in HCV cell culture system in vitro. We found that the percentage corresponding to both TIM-3-positive and CXCR5 + ICOS + Tfh cells within CD4 + T cells, which correlated with HCV RNA replication, was significantly elevated in patients with chronic hepatitis C in comparison with those in NCs. Moreover, blockade of Gal-9/TIM-3 pathway by TIM-3 Fc protein increased Tfh cells proportion, IL-21 mRNA and protein expression within purified CD4 + T cells, while activation of Gal-9/TIM-3 signaling by Gal-9 stimulation decreased IL-21 production in both patients with chronic HCV infection and healthy individuals. Meanwhile, high concentrations (100 and 200ng/mL) of IL-21 stimulation also elevated TIM-3 expression on CD4 + T cells in chronic hepatitis C. Furthermore, TIM-3 blockage and IL-21 stimulation suppressed mRNA expressions of HCV-induced antiviral proteins (myxovirus resistance A and oligoadenylate synthetase) in Huh7.5 cells without affecting viral replication in HCV cell culture system. The interaction between Gal-9/TIM-3 pathway and Tfh cells contributed to viral persistent in chronic HCV infection, which might be pivotal for development of new therapeutic approaches for chronic hepatitis C. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Clinical trials update from the Heart Failure Society of America Meeting 2009: FAST, IMPROVE-HF, COACH galectin-3 substudy, HF-ACTION nuclear substudy, DAD-HF, and MARVEL-1.

PubMed

Lainscak, Mitja; Coletta, Alison P; Sherwi, Nasser; Cleland, John G F

2010-02-01

This article presents findings and a commentary on late-breaking trials presented during the meeting of the Heart Failure Society of America in September 2009. Unpublished reports should be considered as preliminary, since analyses may change in the final publication. The FAST trial showed somewhat better performance of intrathoracic impedance for prediction of deterioration in patients with heart failure (HF) when compared with daily weighing. The IMPROVE-HF study reported the benefits of education on the management of patients with systolic HF. Galectin-3 appeared a useful method for improving risk stratification of patients with chronic HF in a substudy of the COACH trial. A nuclear substudy of the HF-ACTION trial failed to demonstrate that resting myocardial perfusion imaging, a measure of myocardial scar and viability, was clinically useful. A small randomized controlled trial (DAD-HF) suggested that the use of low-dose dopamine in patients with acutely decompensated HF was associated with less deterioration in renal function and less hypokalaemia. The MARVEL-1 trial raises further concerns about the safety of myoblast transplantation in ischaemic HF.

Precision autophagy directed by receptor regulators - emerging examples within the TRIM family.

PubMed

Kimura, Tomonori; Mandell, Michael; Deretic, Vojo

2016-03-01

Selective autophagy entails cooperation between target recognition and assembly of the autophagic apparatus. Target recognition is conducted by receptors that often recognize tags, such as ubiquitin and galectins, although examples of selective autophagy independent of these tags are emerging. It is less known how receptors cooperate with the upstream autophagic regulators, beyond the well-characterized association of receptors with Atg8 or its homologs, such as LC3B (encoded by MAP1LC3B), on autophagic membranes. The molecular details of the emerging role in autophagy of the family of proteins called TRIMs shed light on the coordination between cargo recognition and the assembly and activation of the principal autophagy regulators. In their autophagy roles, TRIMs act both as receptors and as platforms ('receptor regulators') for the assembly of the core autophagy regulators, such as ULK1 and Beclin 1 in their activated state. As autophagic receptors, TRIMs can directly recognize endogenous or exogenous targets, obviating a need for intermediary autophagic tags, such as ubiquitin and galectins. The receptor and regulatory features embodied within the same entity allow TRIMs to govern cargo degradation in a highly exact process termed 'precision autophagy'. © 2016. Published by The Company of Biologists Ltd.

Chemical Shifts of the Carbohydrate Binding Domain of Galectin-3 from Magic Angle Spinning NMR and Hybrid Quantum Mechanics/Molecular Mechanics Calculations.

PubMed

Kraus, Jodi; Gupta, Rupal; Yehl, Jenna; Lu, Manman; Case, David A; Gronenborn, Angela M; Akke, Mikael; Polenova, Tatyana

2018-03-22

Magic angle spinning NMR spectroscopy is uniquely suited to probe the structure and dynamics of insoluble proteins and protein assemblies at atomic resolution, with NMR chemical shifts containing rich information about biomolecular structure. Access to this information, however, is problematic, since accurate quantum mechanical calculation of chemical shifts in proteins remains challenging, particularly for 15 N H . Here we report on isotropic chemical shift predictions for the carbohydrate recognition domain of microcrystalline galectin-3, obtained from using hybrid quantum mechanics/molecular mechanics (QM/MM) calculations, implemented using an automated fragmentation approach, and using very high resolution (0.86 Å lactose-bound and 1.25 Å apo form) X-ray crystal structures. The resolution of the X-ray crystal structure used as an input into the AF-NMR program did not affect the accuracy of the chemical shift calculations to any significant extent. Excellent agreement between experimental and computed shifts is obtained for 13 C α , while larger scatter is observed for 15 N H chemical shifts, which are influenced to a greater extent by electrostatic interactions, hydrogen bonding, and solvation.

A Global Assessment of Circulating Prolysyl Oxidase in Nonischemic Patients With Garden-variety Heart Failure With Preserved Ejection Fraction.

PubMed

Muñoz Calvo, Benjamín; Villa Martínez, Ana; López Orgil, Susana; López Andrés, Natalia; Román García, Feliciano; Víctor Palomares, Virginia; de la Calle de la Villa, Esther; Nadador Patiño, Verónica; Arribas-Gómez, Ignacio

2018-05-25

Lysyl oxidase is overexpressed in the myocardium of patients with hypertensive cardiomyopathy. We aimed to explore whether patients with hypertensive-metabolic heart failure with preserved ejection fraction (HM-HFpEF) also have increased concentrations of circulating prolysyl oxidase (cpLOX) and its possible consequences. We quantified cpLOX concentrations in 85 nonischemic patients with stage C, HM-HFpEF, and compared them with those of 51 healthy controls. We also assessed the correlations of cpLOX with myocardial stiffness parameters, collagen turnover products and fibrogenic cytokines, as well as the predictive value of plasma proenzyme levels at 1-year of follow-up. We detected raised cpLOX values and found that they correlated with calculated E/E' ratios and stiffness constants. The subgroup of patients with type I diastolic dysfunction showed a single negative correlation between cpLOX and B-type natriuretic peptide whereas patients with a restrictive diastolic pattern showed a strong correlation between cpLOX and galectin-3. Kaplan-Meier analysis revealed that cpLOX > 52.20 ng/mL slightly increased the risk of a fatal outcome (log-rank = 4.45; P = .034). When Cox regression was used, cpLOX was found to be a significant independent predictor of cardiovascular death or hospitalization due to the decompensation of HM-HFpEF (HR, 1.360; 95%CI, 1.126-1.638; P = .046). Patients with symptomatic HM-HFpEF show high cpLOX serum levels associated with restrictive diastolic filling indices. These levels represent a moderate risk factor for poor clinical outcome. Throughout the natural history of HM-HFpEF, we observed that cpLOX concentrations were initially negatively correlated with B-type natriuretic peptide but positively correlated with galectin-3 as advanced diastolic dysfunction developed. Copyright © 2018. Published by Elsevier España, S.L.U.

ST6GALNAC1 plays important roles in enhancing cancer stem phenotypes of colorectal cancer via the Akt pathway

PubMed Central

Ogawa, Tadashi; Hirohashi, Yoshihiko; Murai, Aiko; Nishidate, Toshihiko; Okita, Kenji; Wang, Liming; Ikehara, Yuzuru; Satoyoshi, Tetsuta; Usui, Akihiro; Kubo, Terufumi; Nakastugawa, Munehide; Kanaseki, Takayuki; Tsukahara, Tomohide; Kutomi, Goro; Furuhata, Tomohisa; Hirata, Koichi; Sato, Noriyuki; Mizuguchi, Toru; Takemasa, Ichiro; Torigoe, Toshihiko

2017-01-01

Colorectal cancer (CRC) is a mortal disease due to treatment resistance, recurrence and distant metastasis. Emerging evidence has revealed that a small sub-population of cancer cells termed cancer stem cells (CSCs)/ cancer-initiating cells (CICs) is endowed with high levels of tumor-initiating ability, self-renewal ability and differentiation ability and is responsible for treatment resistance, recurrence and distant metastasis. Eradication of CSCs/CICs is essential to improve current treatments. However, the molecular mechanisms by which CSCs/CICs are maintained are still elusive. In this study, we aimed to determine the molecular mechanisms by which colorectal (CR)-CSCs/CICs in are maintained human primary CRC cells. CR-CSCs/CICs were isolated by sphere-culture and the ALDEFLUOR assay, and transcriptome analysis revealed that the gene ST6 N-Acetylgalactosaminide Alpha-2,6-Sialyltransferase 1 (ST6GALNAC1) was expressed at high levels in CR-CSCs/CICs. Overexpression of ST6GALNAC1 enhanced the expression of sialyl-Tn (STn) antigen, which is carried by the CSC marker CD44, and increased the sphere-forming ability and resistance to a chemotherapeutic reagent. The opposite phenomena were observed by gene knockdown using siRNA. Furthermore, the Akt pathway was activated in ST6GANAC1-overexpressed cells, and activation of the pathway was cancelled by gene knockdown of galectin-3. The results indicate that ST6GALNAC1 has a role in the maintenance of CR-CSCs/CICs by activating the Akt pathway in cooperation with galectin-3 and that ST6GalNAC1 (or STn antigen) might be a reasonable molecule for CSC/CIC-targeting therapy. PMID:29348846

Structural Divergence in Vertebrate Phylogeny of a Duplicated Prototype Galectin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhat, R.; Chakraborty, M.; Mian, I. S.

Prototype galectins, endogenously expressed animal lectins with a single carbohydrate recognition domain, are well-known regulators of tissue properties such as growth and adhesion. The earliest discovered and best studied of the prototype galectins is Galectin-1 (Gal-1). In the Gallus gallus (chicken) genome, Gal-1 is represented by two homologs: Gal-1A and Gal-1B, with distinct biochemical properties, tissue expression, and developmental functions. We investigated the origin of the Gal-1A/Gal-1B divergence to gain insight into when their developmental functions originated and how they could have contributed to vertebrate phenotypic evolution. Sequence alignment and phylogenetic tree construction showed that the Gal-1A/Gal-1B divergence can bemore » traced back to the origin of the sauropsid lineage (consisting of extinct and extant reptiles and birds) although lineage-specific duplications also occurred in the amphibian and actinopterygian genomes. Gene synteny analysis showed that sauropsid gal-1b (the gene for Gal-1B) and its frog and actinopterygian gal-1 homologs share a similar chromosomal location, whereas sauropsid gal-1a has translocated to a new position. Surprisingly, we found that chicken Gal-1A, encoded by the translocated gal-1a, was more similar in its tertiary folding pattern than Gal-1B, encoded by the untranslocated gal-1b, to experimentally determined and predicted folds of nonsauropsid Gal-1s. This inference is consistent with our finding of a lower proportion of conserved residues in sauropsid Gal-1Bs, and evidence for positive selection of sauropsid gal-1b, but not gal-1a genes. We propose that the duplication and structural divergence of Gal-1B away from Gal-1A led to specialization in both expression and function in the sauropsid lineage.« less

Structural Divergence in Vertebrate Phylogeny of a Duplicated Prototype Galectin

DOE PAGES

Bhat, R.; Chakraborty, M.; Mian, I. S.; ...

2014-09-25

Prototype galectins, endogenously expressed animal lectins with a single carbohydrate recognition domain, are well-known regulators of tissue properties such as growth and adhesion. The earliest discovered and best studied of the prototype galectins is Galectin-1 (Gal-1). In the Gallus gallus (chicken) genome, Gal-1 is represented by two homologs: Gal-1A and Gal-1B, with distinct biochemical properties, tissue expression, and developmental functions. We investigated the origin of the Gal-1A/Gal-1B divergence to gain insight into when their developmental functions originated and how they could have contributed to vertebrate phenotypic evolution. Sequence alignment and phylogenetic tree construction showed that the Gal-1A/Gal-1B divergence can bemore » traced back to the origin of the sauropsid lineage (consisting of extinct and extant reptiles and birds) although lineage-specific duplications also occurred in the amphibian and actinopterygian genomes. Gene synteny analysis showed that sauropsid gal-1b (the gene for Gal-1B) and its frog and actinopterygian gal-1 homologs share a similar chromosomal location, whereas sauropsid gal-1a has translocated to a new position. Surprisingly, we found that chicken Gal-1A, encoded by the translocated gal-1a, was more similar in its tertiary folding pattern than Gal-1B, encoded by the untranslocated gal-1b, to experimentally determined and predicted folds of nonsauropsid Gal-1s. This inference is consistent with our finding of a lower proportion of conserved residues in sauropsid Gal-1Bs, and evidence for positive selection of sauropsid gal-1b, but not gal-1a genes. We propose that the duplication and structural divergence of Gal-1B away from Gal-1A led to specialization in both expression and function in the sauropsid lineage.« less

Glycobiology of the ocular surface: Mucins and lectins

PubMed Central

Argüeso, Pablo

2013-01-01

Glycosylation is an important and common form of posttranscriptional modification of proteins in cells. A vast array of biological functions has been ascribed to glycans during the last decade thanks to a rapid evolution in glycomic technologies. Glycogenes highly expressed at the human ocular surface include families of glycosyltransferases, proteoglycans, glycan degradation proteins, as well as mucins and carbohydrate-binding proteins such as the galectins. On the apical glycocalyx, mucin O-glycans promote boundary lubrication, prevent bacterial adhesion and endocytic activity, and maintain epithelial barrier function through interactions with galectins. The emerging roles attributed to glycans are contributing to the appreciation of their biological capabilities at the ocular surface. PMID:23325272

Dectin 1 activation on macrophages by galectin 9 promotes pancreatic carcinoma and peritumoral immune tolerance.

PubMed

Daley, Donnele; Mani, Vishnu R; Mohan, Navyatha; Akkad, Neha; Ochi, Atsuo; Heindel, Daniel W; Lee, Ki Buom; Zambirinis, Constantinos P; Pandian, Gautam Sd Balasubramania; Savadkar, Shivraj; Torres-Hernandez, Alejandro; Nayak, Shruti; Wang, Ding; Hundeyin, Mautin; Diskin, Brian; Aykut, Berk; Werba, Gregor; Barilla, Rocky M; Rodriguez, Robert; Chang, Steven; Gardner, Lawrence; Mahal, Lara K; Ueberheide, Beatrix; Miller, George

2017-05-01

The progression of pancreatic oncogenesis requires immune-suppressive inflammation in cooperation with oncogenic mutations. However, the drivers of intratumoral immune tolerance are uncertain. Dectin 1 is an innate immune receptor crucial for anti-fungal immunity, but its role in sterile inflammation and oncogenesis has not been well defined. Furthermore, non-pathogen-derived ligands for dectin 1 have not been characterized. We found that dectin 1 is highly expressed on macrophages in pancreatic ductal adenocarcinoma (PDA). Dectin 1 ligation accelerated the progression of PDA in mice, whereas deletion of Clec7a-the gene encoding dectin 1-or blockade of dectin 1 downstream signaling was protective. We found that dectin 1 can ligate the lectin galectin 9 in mouse and human PDA, which results in tolerogenic macrophage programming and adaptive immune suppression. Upon disruption of the dectin 1-galectin 9 axis, CD4 + and CD8 + T cells, which are dispensable for PDA progression in hosts with an intact signaling axis, become reprogrammed into indispensable mediators of anti-tumor immunity. These data suggest that targeting dectin 1 signaling is an attractive strategy for developing an immunotherapy for PDA.

Low meprin α expression differentiates primary ovarian mucinous carcinoma from gastrointestinal cancers that commonly metastasise to the ovaries

PubMed Central

Heinzelmann‐Schwarz, Viola A; Scolyer, Richard A; Scurry, James P; Smith, Alison N; Gardiner‐Garden, Margaret; Biankin, Andrew V; Baron‐Hay, Sally; Scott, Carolyn; Ward, Robyn L; Fink, Daniel; Hacker, Neville F; Sutherland, Robert L; O'Brien, Philippa M

2007-01-01

Background Currently, no specific immunohistochemical markers are available to differentiate primary mucinous epithelial ovarian cancer (MOC) from adenocarcinomas originating at other sites that have metastasised to the ovary, which may have an impact on patient management and prognosis. Aim To investigate the expression of two intestinal markers, galectin 4 and meprin α, in mucinous carcinomas of the ovary and gastrointestinal tract. Methods Using immunohistochemical analysis, the expression of galectin 4 and meprin α was investigated in 10 MOCs and in 38 mucinous adenocarcinomas of colon, pancreas, stomach and appendix, the most common sites of origin of ovarian metastases. Results Total cytoplasmic galectin 4 expression was relatively consistent between the different carcinomas. Membranous meprin α expression was significantly lower in MOCs compared with gastrointestinal carcinomas. Moreover, meprin α expression showed greater discrimination between the ovarian and gastrointestinal carcinomas than the cytokeratins CK7 and CK20, the current standard immunohistochemical markers used to determine the tissue origin of mucinous carcinomas involving the ovaries. Conclusions Meprin α is a useful additional marker in differentiating primary from secondary mucinous adenocarcinomas of the ovary. PMID:16822880

Analysis of changes in hepatic gene expression in a murine model of tolerance to acetaminophen hepatotoxicity (autoprotection)

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Connor, Meeghan A., E-mail: meeghan.oconnor@boehringer-ingelheim.com; Boehringer Ingelheim Pharmaceuticals Inc., 900 Ridgebury Road, Ridgefield, CT 06877-0368; Koza-Taylor, Petra, E-mail: petra.h.koza-taylor@pfizer.com

Pretreatment of mice with a low hepatotoxic dose of acetaminophen (APAP) results in resistance to a subsequent, higher dose of APAP. This mouse model, termed APAP autoprotection was used here to identify differentially expressed genes and cellular pathways that could contribute to this development of resistance to hepatotoxicity. Male C57BL/6J mice were pretreated with APAP (400 mg/kg) and then challenged 48 h later with 600 mg APAP/kg. Livers were obtained 4 or 24 h later and total hepatic RNA was isolated and hybridized to Affymetrix Mouse Genome MU430{sub 2} GeneChip. Statistically significant genes were determined and gene expression changes weremore » also interrogated using the Causal Reasoning Engine (CRE). Extensive literature review narrowed our focus to methionine adenosyl transferase-1 alpha (MAT1A), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), flavin-containing monooxygenase 3 (Fmo3) and galectin-3 (Lgals3). Down-regulation of MAT1A could lead to decreases in S-adenosylmethionine (SAMe), which is known to protect against APAP toxicity. Nrf2 activation is expected to play a role in protective adaptation. Up-regulation of Lgals3, one of the genes supporting the Nrf2 hypothesis, can lead to suppression of apoptosis and reduced mitochondrial dysfunction. Fmo3 induction suggests the involvement of an enzyme not known to metabolize APAP in the development of tolerance to APAP toxicity. Subsequent quantitative RT-PCR and immunochemical analysis confirmed the differential expression of some of these genes in the APAP autoprotection model. In conclusion, our genomics strategy identified cellular pathways that might further explain the molecular basis for APAP autoprotection. - Highlights: • Differential expression of genes in mice resistant to acetaminophen hepatotoxicity. • Increased gene expression of Flavin-containing monooxygenase 3 and Galectin-3. • Decrease in MAT1A expression and compensatory hepatocellular regeneration. • Two distinct gene expression patterns support contrasting Nrf2 responses. • Genomics identification of pathways relevant to resistance to APAP hepatotoxicity.« less

Role of Matricellular Proteins in Disorders of the Central Nervous System.

PubMed

Jayakumar, A R; Apeksha, A; Norenberg, M D

2017-03-01

Matricellular proteins (MCPs) are actively expressed non-structural proteins present in the extracellular matrix, which rapidly turnover and possess regulatory roles, as well as mediate cell-cell interactions. MCPs characteristically contain binding sites for other extracellular proteins, cell surface receptors, growth factors, cytokines and proteases, that provide structural support for surrounding cells. MCPs are present in most organs, including brain, and play a major role in cell-cell interactions and tissue repair. Among the MCPs found in brain include thrombospondin-1/2, secreted protein acidic and rich in cysteine family (SPARC), including Hevin/SC1, Tenascin C and CYR61/Connective Tissue Growth Factor/Nov family of proteins, glypicans, galectins, plasminogen activator inhibitor (PAI-1), autotaxin, fibulin and perisostin. This review summarizes the potential role of MCPs in the pathogenesis of major neurological disorders, including Alzheimer's disease, amyotrophic lateral sclerosis, ischemia, trauma, hepatic encephalopathy, Down's syndrome, autism, multiple sclerosis, brain neoplasms, Parkinson's disease and epilepsy. Potential therapeutic opportunities of MCP's for these disorders are also considered in this review.

Expression of galectin-3, cytokeratin 19, neural cell adhesion molecule and E-cadhedrin in certain variants of papillary thyroid carcinoma.

PubMed

Laco, J; Ryska, A; Cáp, J; Celakovský, P

2008-10-01

The immunohistochemical expression of galectin-3 (Gal3), cytokeratin 19 (CK19), neural cell adhesion molecule (NCAM), and E-cadherin (Ecad) was evaluated to assess their use in diagnostics of papillary thyroid carcinoma (PTC). A total of 84 PTCs - 36 classical variants (cPTCs), 26 follicular variants (fPTCs), and 22 papillary microcarcinomas (mPTCs) were studied. Expression of Gal3 was found in 36/36 (100%) cPTCs, 24/26 (92%) fPTCs, and 19/22 (86%) mPTCs. CK19 expression was detected in 34/36 (94%) cPTCs, 17/26 (65%) fPTCs, and 13/22 (59%) mPTCs. Expression of NCAM was seen in 5/36 (14%) cPTCs, 7/26 (27%) fPTCs, and 9/22 (41%) mPTCs. Ecad expression was found in 23/36 (64%) cPTCs, 17/26 (65%) fPTCs, and 18/22 (82%) mPTCs. A significant difference in CK19 expression was observed between cPTC and both fPTC and mPTC (p < 0.001). Furthermore, extrathyroid tumor spread significantly correlated with both level of CK19 expression and loss of Ecad expression (p = 0.001, p = 0.04). Our findings suggest that Gal3 and CK19 are useful markers for PTC, although decreased CK19 expression in mPTC and fPTC must be considered. Furthermore, CK19 and Ecad may play a role in extrathyroid tumor spread.

Methods for the detection and serum depletion of porcine galectin-3.

PubMed

Eliaz, Isaac; Patil, Aarti; Navarro-Alvarez, Nalu; Wang, Zhirui; Eliaz, Amity; Weil, Elaine; Wilk, Barry; Sachs, David H; Huang, Christene A

2017-10-01

Circulating galectin-3 (Gal-3) is elevated in systemic inflammatory disorders, fibrotic diseases, and in cancers. Gal-3 is a promising cancer target where it promotes tumorigenesis and metastasis, as well as in renal, pulmonary, hepatic, and cardiovascular diseases, because of its role as a driver of fibrotic remodeling. This reports goal was to establish methods for the detection and removal of porcine Gal-3 that will enable further studies of the therapeutic potential of Gal-3 depletion by apheresis in porcine disease models. The long-term aim is to develop a safe, effective method of removing Gal-3 via apheresis as a standalone therapeutic tool and as an adjuvant to other therapies. Purified recombinant porcine Gal-3 was prepared and used as the standard for development of a porcine Gal-3 enzyme-linked immunosorbent assay (ELISA). Different affinity column matrices that incorporated either a rat IgG2a anti-Gal-3 monoclonal antibody or carbohydrate ligand were assessed for depletion of Gal-3 from porcine serum. A porcine Gal-3 ELISA with a linear range from 0.3 to 20 ng/mL was able to detect native porcine Gal-3 in both fetal (∼150-200 ng/mL) and juvenile (∼5-15 ng/mL) porcine serum samples. Use of an anti-Gal-3 monoclonal antibody affinity column depleted Gal-3 from porcine serum to at least 313 pg/mL, the limit of ELISA detection. Methods have been developed for the detection and depletion of porcine Gal-3. These methods will be used to study the specific effects of Gal-3 depletion via apheresis in porcine models of disease. © 2017 Wiley Periodicals, Inc.

Co-administration of rivaroxaban with drugs that share its elimination pathways: pharmacokinetic effects in healthy subjects

PubMed Central

Mueck, Wolfgang; Kubitza, Dagmar; Becka, Michael

2013-01-01

Aims The anticoagulant rivaroxaban is an oral, direct Factor Xa inhibitor for the management of thromboembolic disorders. Metabolism and excretion involve cytochrome P450 3A4 (CYP3A4) and 2J2 (CYP2J2), CYP-independent mechanisms, and P-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp) (ABCG2). Methods The pharmacokinetic effects of substrates or inhibitors of CYP3A4, P-gp and Bcrp (ABCG2) on rivaroxaban were studied in healthy volunteers. Results Rivaroxaban did not interact with midazolam (CYP3A4 probe substrate). Exposure to rivaroxaban when co-administered with midazolam was slightly decreased by 11% (95% confidence interval [CI] −28%, 7%) compared with rivaroxaban alone. The following drugs moderately affected rivaroxaban exposure, but not to a clinically relevant extent: erythromycin (moderate CYP3A4/P-gp inhibitor; 34% increase [95% CI 23%, 46%]), clarithromycin (strong CYP3A4/moderate P-gp inhibitor; 54% increase [95% CI 44%, 64%]) and fluconazole (moderate CYP3A4, possible Bcrp [ABCG2] inhibitor; 42% increase [95% CI 29%, 56%]). A significant increase in rivaroxaban exposure was demonstrated with the strong CYP3A4, P-gp/Bcrp (ABCG2) inhibitors (and potential CYP2J2 inhibitors) ketoconazole (158% increase [95% CI 136%, 182%] for a 400 mg once daily dose) and ritonavir (153% increase [95% CI 134%, 174%]). Conclusions Results suggest that rivaroxaban may be co-administered with CYP3A4 and/or P-gp substrates/moderate inhibitors, but not with strong combined CYP3A4, P-gp and Bcrp (ABCG2) inhibitors (mainly comprising azole-antimycotics, apart from fluconazole, and HIV protease inhibitors), which are multi-pathway inhibitors of rivaroxaban clearance and elimination. PMID:23305158

A novel β-carotene-associated carrot (Daucus carota L.) pectic polysaccharide.

PubMed

Natarajmurthy, Sindhuja H; Askari, Marjan; Pullabhatla, Srinivas; Dharmesh, Shylaja M

2016-01-01

Carrot (Daucus carota L.) is a nutritional source with enriched β-carotene (0.01%) and pectins (0.8%). Although studies have highlighted the association between β-carotene and carrot pectic polysaccharide (CRPP), the precise binding of β-carotene to CRPP and its biological implications were not yet clearly understood. The aim of the present study is to report for the first time a natural carbohydrate polymer-CRPP-with associated β-carotene. The presence of β-carotene in CRPP and its binding is demonstrated by various studies including differential extraction followed by liquid chromatography (LC), liquid chromatography mass spectrometry (LC MS), and Fourier transform infrared spectroscopy (FTIR). Further, we show the binding via its release from CRPP using LC, fermentation studies and scanning electron microscopy (SEM) studies. The role of β-carotene in induction of apoptosis and the galactic-3 inhibitory property was also studied. The presence of β-carotene in CRPP was demonstrated, as well as an association between β-carotene and CRPP, apoptotic and galectin-3 inhibitory properties of CRPP, and upregulation of connexin 43 by CRPP. The data highlights that with the combination of β-carotene with CRPP, the prooxidant effect of β-carotene may be reduced, an apoptotic effect may be enhanced, and the anticancer potential of CRPP thus may be strengthened via galectin-3 inhibition. Copyright © 2016 Elsevier Inc. All rights reserved.

Elevated systemic galectin-1 levels characterize HELLP syndrome.

PubMed

Schnabel, Annegret; Blois, Sandra M; Meint, Peter; Freitag, Nancy; Ernst, Wolfgang; Barrientos, Gabriela; Conrad, Melanie L; Rose, Matthias; Seelbach-Göbel, Birgit

2016-04-01

Galectin-1 (gal-1), a member of a family of conserved β-galactoside-binding proteins, has been shown to exert a key role during gestation. Though gal-1 is expressed at higher levels in the placenta from HELLP patients, it is still poorly understood whether systemic gal-1 levels also differ in HELLP patients. In the present study, we evaluated the systemic expression of gal-1, together with the angiogenic factors, placental growth factor (PlGF) and soluble fms-like tyrosine kinase 1 (sFlt-1) in conjunction with HELLP syndrome severity. Systemic levels of gal-1 and sFlt-1 were elevated in patients with both early- and late-onset HELLP syndrome as compared to healthy controls. In contrast, peripheral PlGF levels were decreased in early- and late-onset HELLP. A positive correlation between systemic gal-1 levels and sFlt-1/PlGF ratios was found in early onset HELLP patients. Our results show that HELLP syndrome is associated with increased circulating levels of gal-1; integrating systemic gal-1 measurements into the diagnostic analyses of pregnant women may provide more effective prediction of HELLP syndrome development. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Pregestational type 2 diabetes mellitus induces cardiac hypertrophy in the murine embryo through cardiac remodeling and fibrosis.

PubMed

Lin, Xue; Yang, Penghua; Reece, E Albert; Yang, Peixin

2017-08-01

Cardiac hypertrophy is highly prevalent in patients with type 2 diabetes mellitus. Experimental evidence has implied that pregnant women with type 2 diabetes mellitus and their children are at an increased risk of cardiovascular diseases. Our previous mouse model study revealed that maternal type 2 diabetes mellitus induces structural heart defects in their offspring. This study aims to determine whether maternal type 2 diabetes mellitus induces embryonic heart hypertrophy in a murine model of diabetic embryopathy. The type 2 diabetes mellitus embryopathy model was established by feeding 4-week-old female C57BL/6J mice with a high-fat diet for 15 weeks. Cardiac hypertrophy in embryos at embryonic day 17.5 was characterized by measuring heart size and thickness of the right and left ventricle walls and the interventricular septum, as well as the expression of β-myosin heavy chain, atrial natriuretic peptide, insulin-like growth factor-1, desmin, and adrenomedullin. Cardiac remodeling was determined by collagen synthesis and fibronectin synthesis. Fibrosis was evaluated by Masson staining and determining the expression of connective tissue growth factor, osteopontin, and galectin-3 genes. Cell apoptosis also was measured in the developing heart. The thicknesses of the left ventricle walls and the interventricular septum of embryonic hearts exposed to maternal diabetes were significantly thicker than those in the nondiabetic group. Maternal diabetes significantly increased β-myosin heavy chain, atrial natriuretic peptide, insulin-like growth factor-1, and desmin expression, but decreased expression of adrenomedullin. Moreover, collagen synthesis was significantly elevated, whereas fibronectin synthesis was suppressed, in embryonic hearts from diabetic dams, suggesting that cardiac remodeling is a contributing factor to cardiac hypertrophy. The cardiac fibrosis marker, galectin-3, was induced by maternal diabetes. Furthermore, maternal type 2 diabetes mellitus activated the proapoptotic c-Jun-N-terminal kinase 1/2 stress signaling and triggered cell apoptosis by increasing the number of terminal deoxynucleotidyl transferase 2'-deoxyuridine 5'-triphosphate nick end labeling-positive cells (10.4 ± 2.2% of the type 2 diabetes mellitus group vs 3.8 ± 0.7% of the nondiabetic group, P < .05). Maternal type 2 diabetes mellitus induces cardiac hypertrophy in embryonic hearts. Adverse cardiac remodeling, including elevated collagen synthesis, suppressed fibronectin synthesis, profibrosis, and apoptosis, is implicated as the etiology of cardiac hypertrophy. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of in situ expression of effector and regulatory cytokines, TLR, galectins and matrix metalloproteinases in oral manifestations of paracoccidioidomycosis.

PubMed

de Araújo, Marcelo Sivieri; Alves, Polyanna Miranda; de Lima, Lilian Margareth Biagioni; da Silva, Marcelo Fernandes; de Lima Pereira, Sanívia Aparecida; Rodrigues, Virmondes; Rodrigues, Denise Bertulucci Rocha

2015-01-01

Although the pathophysiology of paracoccidioidomycosis (PCM) is not completely understood, the study of immune response against fungus has provided insight into understanding the natural course of the disease and its clinical manifestations, hence contributing to the development of preventive measures and treatment proposals. The aim of this study was to evaluate the histopathological and immunological aspects involved in the role of different effector and regulatory responses, as well as the correlation between the TLRs, Galectins, Matrix Metalloproteinases and cytoplasmic proteases of mast cells in this infection. Sixteen biopsy specimens with oral lesions of chronic PCM, as well as 13 sections of normal oral mucosa were analyzed. Histopathological and immunological aspects involved in the role of different effector and regulatory responses were evaluated. Indirect immunohistochemistry was performed for IL-17, IL-10, IL-4, TGF-β, FoxP3, Gal-1, Gal-3, Gal-9, TLR-2, TLR-4, MMP-3 and MMP-9, as well as for chymase and tryptase for mast cells identification. Fibrosis was quantified using Picrosirius. There was a significant increase in the area of fibrosis and in the number of cells expressing IL-10, IL-4, IL-17, FoxP3, Gal-3, TLR-2, MMP3 and MMP9 in patients with PCM in comparison with patients in the group control. There was no difference in the expression of TGF-β, TLR-4, Gal-1 or Gal-9. Mast cells number was found to be significantly lower in oral chronic PCM when compared to control samples after quantification of mast cells and expression of chymase and tryptase. PCM granulomas were classified to the morphological aspects in organized ou non-organized. Expression of IL-4 in non-organized granulomas was significantly higher. The proteins studied herein appear to play an important role in the development and maintenance of oral lesions of PCM, as well as in the processes of development and progression of lesions caused by the fungus and by the immune response associated with the infection. Copyright © 2014 Elsevier GmbH. All rights reserved.

Transient gene silencing of galectin-3 suppresses pancreatic cancer cell migration and invasion through degradation of β-catenin

PubMed Central

Kobayashi, Tsutomu; Shimura, Tatsuo; Yajima, Toshiki; Kubo, Norio; Araki, Kenichiro; Tsutsumi, Soichi; Suzuki, Hideki; Kuwano, Hiroyuki; Raz, Avraham

2013-01-01

Pancreatic cancer is a leading cause of cancer-related mortality and often has a poor prognosis because of its late diagnosis, aggressive local invasion, early metastasis, and poor response to chemotherapy. The chemotherapeutic agent gemcitabine is effective for treating advanced pancreatic cancer, but its efficacy remains less than satisfactory. It is expected that further investigation of pancreatic cancer cell invasion and development of strategies to block this process should improve the disease prognosis. In this study, we tested our hypothesis that galectin-3 (gal-3), a multifunctional member of the β-galactoside-binding protein family, may regulate pancreatic cancer cell motility, and silencing of it inhibit cell motility. Previous studies demonstrated that this protein is associated with tumor cell adhesion, proliferation, differentiation, angiogenesis, apoptosis, and metastasis. Here, we used gal-3 small interfering RNA (siRNA) to silence its expression in various pancreatic cancer cell lines to determine whether gal-3 regulates cell proliferation, migration and invasion in vitro. We found that silencing gal-3 reduced cellular migration and invasion, but failed to affect proliferation. In gal-3 siRNA-transfected cells, we detected a decrease in β-catenin expression, an important signal for cancer cell invasion, which was caused by down-regulation of phosphorylated Akt and GSK-3β. We also found that matrix metalloproteinase (MMP)-2 expression was reduced by gal-3 silencing. These results indicate that gal-3-mediated invasion via MMP-2 regulated by β-catenin degradation is initiated by Akt phosphorylation in pancreatic cancer cells. Our results suggest that gal-3 can be a novel therapeutic target in pancreatic cancer. PMID:21448903

Positive associations between galectin-3 and PSA levels in prostate cancer patients: a prospective clinical study-I.

PubMed

Nakajima, Kosei; Heilbrun, Lance K; Hogan, Victor; Smith, Daryn; Heath, Elisabeth; Raz, Avraham

2016-12-13

Galectin-3 (Gal-3), an oncogenic pro-inflammatory protein, has been suggested as a possible complementary diagnostic candidate to prostate specific antigen (PSA) blood test for prostate cancer patients. The presence of the proteins in the circulation (biomarkers) may elicit an intrinsic humoral immune reaction by generating autoantibodies, which consequently could alter the detection levels. Here, we report the associations of the two prostate cancer biomarkers, Gal-3 and PSA in patients at different clinical states of prostate cancer while taking into account the autoantibody levels. A blind, prospective, single institution, pilot study was conducted. A total of 95 men were classified into 5 groups: healthy controls (Group1), newly diagnosed patients (Group2), no recurrence after local therapy (Group3), rising PSA after local therapy (Group4), and metastatic patients (Group5). Gal-3 and PSA level were divided by their respective autoantibodies, which yielded relative PSA and relative Gal-3 levels. After the adjustments, Spearman's rank correlations and linear regression modeling revealed the positive associations between relative Gal-3 and relative PSA levels among all 95 men combined (rho = 0.446, P < 0.0001; fitted slope 0.448, P < 0.0001), in Group2 (rho = 0.616, P = 0.0050; fitted slope 0.438, P =0.0011), and Group3 (rho = 0.484, P = 0.0360; fitted slope 0.470, P = 0.0187). The data show positive associations of relative Gal-3 and relative PSA levels in prostate cancer patients, notably at early clinical time course. Allowing for the influence of autoantibodies, Gal-3 level might be considered as a potential biomarker since it is positively associated with PSA level.

Galectin-8 regulates targeting of Gp135/podocalyxin and lumen formation at the apical surface of renal epithelial cells.

PubMed

Lim, HooiCheng; Yu, Chun-Ying; Jou, Tzuu-Shuh

2017-11-01

Establishment of apical-basal polarity, through correct targeting of polarity determinants to distinct domains of the plasma membrane, is a fundamental process for the development of functioning epithelial tubules. Here we report that galectin (Gal)-8 regulates apical-basal polarity of Madin-Darby canine kidney (MDCK) cells via apical targeting of 135-kDa glycoprotein (Gp135). Gal-8 interacts with newly synthesized Gp135 in a glycan-dependent manner. Gal-8 knockdown induces aberrant lumens at the lateral domain and mistargeting of Gp135 to this structure, thus disrupting the kidney epithelial polarity of MDCK cells, which organize lumens at the apical surface. The O -glycosylation deletion mutant of Gp135 phenocopies the effect of Gal-8 knockdown, which suggests that Gal-8 is the decoding machinery for the apical sorting signals of Gp135 residing at its O -glycosylation-rich region. Collectively, our results reveal a new role of Gal-8 in the development of luminal organs by regulating targeting of apical polarity protein Gp135.-Lim, H., Yu, C.-Y., Jou, T.-S. Galectin-8 regulates targeting of Gp135/podocalyxin and lumen formation at the apical surface of renal epithelial cells. © FASEB.

Prognostic Value of the Interaction between Galectin-3 and Antigen Carbohydrate 125 in Acute Heart Failure

PubMed Central

Núñez, Julio; Rabinovich, Gabriel A.; Sandino, Justo; Mainar, Luis; Palau, Patricia; Santas, Enrique; Villanueva, Maria Pilar; Núñez, Eduardo; Bodí, Vicent; Chorro, Francisco J.; Miñana, Gema; Sanchis, Juan

2015-01-01

Aims Galectin-3 (Gal-3) and carbohydrate antigen 125 (CA125) have emerged as robust prognostic biomarkers in heart failure. Experimental data have also suggested a potential molecular interaction between CA125 and Gal-3; however, the biological and clinical relevance of this interaction is still uncertain. We sought to evaluate, in patients admitted for acute heart failure, the association between plasma Gal-3 with all-cause mortality and the risk for rehospitalizations among high and low levels of CA125. Methods and Results We included 264 consecutive patients admitted for acute heart failure to the Cardiology Department in a third-level center. Both biomarkers were measured on admission. Negative binomial and Cox regression models were used to evaluate the prognostic effect of the interaction between Gal-3 and CA125 (dichotomized by its median) with hospital readmission and all-cause mortality, respectively. During a median follow-up of 2 years (IQR = 1-2.8), 108 (40.9%) patients deaths and 365 rehospitalizations in 171 (69.5%) patients were registered. In a multivariable setting, the effect of Gal-3 on mortality and rehospitalization was differentially mediated by CA125 (p = 0.007 and p<0.001, respectively). Indeed, in patients with CA125 above median (>67 U/ml), values across the continuum of Gal-3 showed a positive and almost linear relationship with either the risk of death or rehospitalization. Conversely, when CA125 was below median (≤67 U/ml), Gal-3 lacked any prognostic effect on both endpoints. Conclusion In patients with acute heart failure, Gal-3 was strongly associated with higher risk of long-term mortality and repeated rehospitalizations, but only in those patients exhibiting higher values of CA125 (above 67 U/ml). PMID:25875367

Microglial Lectins in Health and Neurological Diseases

PubMed Central

Siew, Jian Jing; Chern, Yijuang

2018-01-01

Microglia are the innate sentinels of the central nervous system (CNS) and are responsible for the homeostasis and immune defense of the CNS. Under the influence of the local environment and cell-cell interaction, microglia exhibit a multidimensional and context-dependent phenotypes that can be cytotoxic and neuroprotective. Recent studies suggest that microglia express multitudinous types of lectins, including galectins, Siglecs, mannose-binding lectins (MBLs) and other glycan binding proteins. Because most studies that examine lectins focus on the peripheral system, the functions of lectins have not been critically investigated in the CNS. In addition, the types of brain cells that contribute to the altered levels of lectins present in diseases are often unclear. In this review, we will discuss how galectins, Siglecs, selectins and MBLs contribute to the dynamic functions of microglia. The interacting ligands of these lectins are complex glycoconjugates, which consist of glycoproteins and glycolipids that are expressed on microglia or surrounding cells. The current understanding of the heterogeneity and functions of glycans in the brain is limited. Galectins are a group of pleotropic proteins that recognize both β-galactoside-containing glycans and non- β-galactoside-containing proteins. The function and regulation of galectins have been implicated in immunomodulation, neuroinflammation, apoptosis, phagocytosis and oxidative bursts. Most Siglecs are expressed at a low level on the plasma membrane and bind to sialic acid residues for immunosurveillance and cell-cell communication. Siglecs are classified based on their inhibitory and activatory downstream signaling properties. Inhibitory Siglecs negatively regulate microglia activation upon recognizing the intact sialic acid patterns and vice versa. MBLs are expressed upon infection in cytoplasm and can be secreted in order to recognize molecules containing terminal mannose as an innate immune defense machinery. Most importantly, multiple studies have reported dysregulation of lectins in neurological disorders. Here, we reviewed recent studies on microglial lectins and their functions in CNS health and disease, and suggest that these lectin families are novel, potent therapeutic targets for neurological diseases. PMID:29867350

Loss of Bin1 Promotes the Propagation of Tau Pathology.

PubMed

Calafate, Sara; Flavin, William; Verstreken, Patrik; Moechars, Diederik

2016-10-18

Tau pathology propagates within synaptically connected neuronal circuits, but the underlying mechanisms are unclear. BIN1-amphiphysin2 is the second most prevalent genetic risk factor for late-onset Alzheimer's disease. In diseased brains, the BIN1-amphiphysin2 neuronal isoform is downregulated. Here, we show that lowering BIN1-amphiphysin2 levels in neurons promotes Tau pathology propagation whereas overexpression of neuronal BIN1-amphiphysin2 inhibits the process in two in vitro models. Increased Tau propagation is caused by increased endocytosis, given our finding that BIN1-amphiphysin2 negatively regulates endocytic flux. Furthermore, blocking endocytosis by inhibiting dynamin also reduces Tau pathology propagation. Using a galectin-3-binding assay, we show that internalized Tau aggregates damage the endosomal membrane, allowing internalized aggregates to leak into the cytoplasm to propagate pathology. Our work indicates that lower BIN1 levels promote the propagation of Tau pathology by efficiently increasing aggregate internalization by endocytosis and endosomal trafficking. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

DIOL Triterpenes Block Profibrotic Effects of Angiotensin II and Protect from Cardiac Hypertrophy

PubMed Central

Jurado-López, Raquel; Martínez-Martínez, Ernesto; Gómez-Hurtado, Nieves; Delgado, Carmen; Visitación Bartolomé, Maria; San Román, José Alberto; Cordova, Claudia; Lahera, Vicente; Nieto, Maria Luisa; Cachofeiro, Victoria

2012-01-01

Background The natural triterpenes, erythrodiol and uvaol, exert anti-inflammatory, vasorelaxing and anti-proliferative effects. Angiotensin II is a well-known profibrotic and proliferative agent that participates in the cardiac remodeling associated with different pathological situations through the stimulation and proliferation of cardiac fibroblasts. Therefore, the aim of the study was to investigate the preventive effects of the natural triterpenes erythrodiol and uvaol on the proliferation and collagen production induced by angiotensin II in cardiac myofibroblasts. Their actions on cardiac hypertrophy triggered by angiotensin II were also studied. Methodology/Principal Findings The effect of erythrodiol and uvaol on angiotensin II-induced proliferation was evaluated in cardiac myofibroblasts from adult rats in the presence or the absence of the inhibitors of PPAR-γ, GW9662 or JNK, SP600125. The effect on collagen levels induced by angiotensin II was evaluated in cardiac myofibroblasts and mouse heart. The presence of low doses of both triterpenes reduced the proliferation of cardiac myofibroblasts induced by angiotensin II. Pretreatment with GW9662 reversed the effect elicited by both triterpenes while SP600125 did not modify it. Both triterpenes at high doses produced an increase in annexing-V binding in the presence or absence of angiotensin II, which was reduced by either SP600125 or GW9662. Erythrodiol and uvaol decreased collagen I and galectin 3 levels induced by angiotensin II in cardiac myofribroblasts. Finally, cardiac hypertrophy, ventricular remodeling, fibrosis, and increases in myocyte area and brain natriuretic peptide levels observed in angiotensin II-infused mice were reduced in triterpene-treated animals. Conclusions/Significance Erythrodiol and uvaol reduce cardiac hypertrophy and left ventricle remodeling induced by angiotensin II in mice by diminishing fibrosis and myocyte area. They also modulate growth and survival of cardiac myofibroblasts. They inhibit the angiotensin II-induced proliferation in a PPAR-γ-dependent manner, while at high doses they activate pathways of programmed cell death that are dependent on JNK and PPAR-γ. PMID:22844495

Galectin-9 enhances cytokine secretion, but suppresses survival and degranulation, in human mast cell line.

PubMed

Kojima, Reiji; Ohno, Tatsukuni; Iikura, Motoyasu; Niki, Toshiro; Hirashima, Mitsuomi; Iwaya, Keichi; Tsuda, Hitoshi; Nonoyama, Shigeaki; Matsuda, Akio; Saito, Hirohisa; Matsumoto, Kenji; Nakae, Susumu

2014-01-01

Galectin-9 (Gal-9), a lectin having a β-galactoside-binding domain, can induce apoptosis of Th1 cells by binding to TIM-3. In addition, Gal-9 inhibits IgE/Ag-mediated degranulation of mast cell/basophilic cell lines by binding to IgE, thus blocking IgE/Ag complex formation. However, the role of Gal-9 in mast cell function in the absence of IgE is not fully understood. Here, we found that recombinant Gal-9 directly induced phosphorylation of Erk1/2 but not p38 MAPK in a human mast cell line, HMC-1, which does not express FcεRI. Gal-9 induced apoptosis and inhibited PMA/ionomycin-mediated degranulation of HMC-1 cells. On the other hand, Gal-9 induced cytokine and/or chemokine production by HMC-1 cells, dependent on activation of ERK1/2 but not p38 MAPK. In addition, the lectin activity of Gal-9 was required for Gal-9-mediated cytokine secretion by HMC-1 cells. These observations suggest that Gal-9 has dual properties as both a regulator and an activator of mast cells.

Proteolytic Activity of Prostate-Specific Antigen (PSA) towards Protein Substrates and Effect of Peptides Stimulating PSA Activity

PubMed Central

Mattsson, Johanna M.; Ravela, Suvi; Hekim, Can; Jonsson, Magnus; Malm, Johan; Närvänen, Ale; Stenman, Ulf-Håkan; Koistinen, Hannu

2014-01-01

Prostate-specific antigen (PSA or kallikrein-related peptidase-3, KLK3) exerts chymotrypsin-like proteolytic activity. The main biological function of PSA is the liquefaction of the clot formed after ejaculation by cleavage of semenogelins I and II in seminal fluid. PSA also cleaves several other substrates, which may explain its putative functions in prostate cancer and its antiangiogenic activity. We compared the proteolytic efficiency of PSA towards several protein and peptide substrates and studied the effect of peptides stimulating the activity of PSA with these substrates. An endothelial cell tube formation model was used to analyze the effect of PSA-degraded protein fragments on angiogenesis. We showed that PSA degrades semenogelins I and II much more efficiently than other previously identified protein substrates, e.g., fibronectin, galectin-3 and IGFBP-3. We identified nidogen-1 as a new substrate for PSA. Peptides B2 and C4 that stimulate the activity of PSA towards small peptide substrates also enhanced the proteolytic activity of PSA towards protein substrates. Nidogen-1, galectin-3 or their fragments produced by PSA did not have any effect on endothelial cell tube formation. Although PSA cleaves several other protein substrates, in addition to semenogelins, the physiological importance of this activity remains speculative. The PSA levels in prostate are very high, but several other highly active proteases, such as hK2 and trypsin, are also expressed in the prostate and may cleave protein substrates that are weakly cleaved by PSA. PMID:25237904

Identification and transcriptional analysis of two types of lectins (SgCTL-1 and SgGal-1) from mollusk Solen grandis.

PubMed

Wei, Xiumei; Yang, Jianmin; Liu, Xiangquan; Yang, Dinglong; Xu, Jie; Fang, Jinghui; Wang, Weijun; Yang, Jialong

2012-08-01

C-type lectin and galectin are two types of animal carbohydrate-binding proteins which serve as pathogen recognition molecules and play crucial roles in the innate immunity of invertebrates. In the present study, a C-type lectin (designated as SgCTL-1) and galectin (designated as SgGal-1) were identified from mollusk Solen grandis, and their expression patterns, both in tissues and toward three pathogen-associated molecular patterns (PAMPs) stimulation were characterized. The full-length cDNA of SgCTL-1 and SgGal-1 was 1280 and 1466 bp, containing an open reading frame (ORF) of 519 and 1218 bp, respectively. Their deduced amino acid sequences showed high similarity to other members of C-type lectin and galectin superfamily, respectively. SgCTL-1 encoded a single carbohydrate-recognition domain (CRD), and the motif of Ca(2+)-binding site 2 was EPN (Glu(135)-Pro(136)-Asn(137)). While SgGal-1 encoded two CRDs, and the amino acid residues constituted the carbohydrate-binding motifs were well conserved in CRD1 but partially conserved in CRD2. Although SgCTL-1 and SgGal-1 exhibited different tissue expression pattern, they were both constitutively expressed in all tested tissues, including hemocytes, gonad, mantle, muscle, gill and hepatopancreas, and they were both highly expressed in hepatopancreas and gill. Furthermore, the mRNA expression of two lectins in hemocytes was significantly (P < 0.01) up-regulated with different levels after S. grandis were stimulated by lipopolysaccharide (LPS), peptidoglycan (PGN) or β-1,3-glucan. Our results suggested that SgCTL-1 and SgGal-1 from razor clam were two novel members of animal lectins, and they might function as pattern recognition receptors (PRRs) taking part in the process of pathogen recognition. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mechanical entrapment is insufficient and intercellular adhesion is essential for metastatic cell arrest in distant organs.

PubMed

Glinskii, Olga V; Huxley, Virginia H; Glinsky, Gennadi V; Pienta, Kenneth J; Raz, Avraham; Glinsky, Vladislav V

2005-05-01

In this report, we challenge a common perception that tumor embolism is a size-limited event of mechanical arrest, occurring in the first capillary bed encountered by blood-borne metastatic cells. We tested the hypothesis that mechanical entrapment alone, in the absence of tumor cell adhesion to blood vessel walls, is not sufficient for metastatic cell arrest in target organ microvasculature. The in vivo metastatic deposit formation assay was used to assess the number and location of fluorescently labeled tumor cells lodged in selected organs and tissues following intravenous inoculation. We report that a significant fraction of breast and prostate cancer cells escapes arrest in a lung capillary bed and lodges successfully in other organs and tissues. Monoclonal antibodies and carbohydrate-based compounds (anti-Thomsen-Friedenreich antigen antibody, anti-galectin-3 antibody, modified citrus pectin, and lactulosyl-l-leucine), targeting specifically beta-galactoside-mediated tumor-endothelial cell adhesive interactions, inhibited by >90% the in vivo formation of breast and prostate carcinoma metastatic deposits in mouse lung and bones. Our results indicate that metastatic cell arrest in target organ microvessels is not a consequence of mechanical trapping, but is supported predominantly by intercellular adhesive interactions mediated by cancer-associated Thomsen-Friedenreich glycoantigen and beta-galactoside-binding lectin galectin-3. Efficient blocking of beta-galactoside-mediated adhesion precludes malignant cell lodging in target organs.

Protective Effect of Adansonia digitata against Isoproterenol-Induced Myocardial Injury in Rats.

PubMed

Ghoneim, Mona A M; Hassan, Amal I; Mahmoud, Manal G; Asker, Mohsen S

2016-01-01

The baobab fruit (Adansonia digitata) was analyzed for proximate composition, amino acids, and minerals. The fruit pulp was found to be a good source of carbohydrates, proteins, phenols, and substantial quantities of K, Ca, and Mg. Amino acid analyses revealed high glutamic and aspartic acid, but the sulfur amino acids were the most limited. The present study was designed to investigate the role of Adansonia digitata (Baobab fruit pulp) against isoproterenol induced myocardial oxidative stress in experimental rats by demonstrating the changes in tissue cardiac markers, some antioxidant enzymes, interleukin-1 β (IL-1 β), monocyte chemoattractant protein-1(MCP-1), myeloperoxidase (MPO), Collagen-1, galectin-3, and serum corticosterone. The activities of enzymatic antioxidant glutathione peroxidase (GPX) and non-enzymatic antioxidant reduced glutathione (GSH) in the heart tissue; additionally, histopathological examination of the heart was estimated. Male albino rats were randomly divided into four groups of ten animals each. Group I served as normal control animal. Group II animals received isoproterenol (ISP) (85 mg/kg body weight intraperitonealy (i.p.) to develop myocardial injury. Group III were myocardial oxidative animals treated with Baobab fruit pulp (200 µg/rats/day) for 4 weeks. Group IV received Baobab fruit pulp only. The data suggested an isoproterenol increase in levels of cardiac marker enzymes [creatine kinase MB (CK- MB), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST)], IL-1ß, MCP-1, MPO, Collagen, and galectin-3, with concomitant decrease in the activities GPX and GSH in heart tissue as well as corticosterone in serum. Baobab fruit pulp brings all the parameters to near normal level in ISP-induced myocardial infarction in rats. Histopathological examination of heart tissue of ISP-administered model rat showed infiltration of inflammatory cells and congestion in the blood vessels. However, treatment with Baobab fruit pulp (200 µg/rats/day) showed predominantly normal myocardial structure and no inflammatory cell infiltration. It has been concluded that Baobab fruit pulp has cardio protective effect against ISP-induced oxidative stress in rats.

Inhibition of SRC-3 enhances sensitivity of human cancer cells to histone deacetylase inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zou, Zhengzhi, E-mail: zouzhengzhi@m.scnu.edu.cn; Luo, Xiaoyong; Nie, Peipei

SRC-3 is widely expressed in multiple tumor types and involved in cancer cell proliferation and apoptosis. Histone deacetylase (HDAC) inhibitors are promising antitumor drugs. However, the poor efficacy of HDAC inhibitors in solid tumors has restricted its further clinical application. Here, we reported the novel finding that depletion of SRC-3 enhanced sensitivity of breast and lung cancer cells to HDAC inhibitors (SAHA and romidepsin). In contrast, overexpression of SRC-3 decreased SAHA-induced cancer cell apoptosis. Furthermore, we found that SRC-3 inhibitor bufalin increased cancer cell apoptosis induced by HDAC inhibitors. The combination of bufalin and SAHA was particular efficient in attenuatingmore » AKT activation and reducing Bcl-2 levels. Taken together, these accumulating data might guide development of new breast and lung cancer therapies. - Highlights: • Depletion of SRC-3 enhanced sensitivity of breast and lung cancer cells to HDAC inhibitors. • Overexpression of SRC-3 enhanced cancer cell resistance to HDAC inhibitors. • SRC-3 inhibitor bufalin increased cancer cell apoptosis induced by HDAC inhibitors. • Bufalin synergized with HDAC inhibitor attenuated AKT activation and reduced Bcl-2 levels in human cancer cell.« less

Electrochemical studies of novel corrosion inhibitor for mild steel in 1 M hydrochloric acid

NASA Astrophysics Data System (ADS)

Al-Amiery, Ahmed A.; Ahmed, Mohammed H. Othman; Abdullah, Thamer Adnan; Gaaz, Tayser Sumer; Kadhum, Abdul Amir H.

2018-06-01

The electrochemical performance of a novel organic corrosion inhibitor 6-(4-hydroxyphenyl)-3-mercapto-7,8-dihydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine [HT3], for mild steel in 1 M hydrochloric acid is evaluated by potentiodynamic curves. The experimental results show that the investigated inhibitor [HT3], which can effectively retard the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing a protective coating for the mild steel that, can be weakened by increasing the temperature. Furthermore, the inhibition efficiency of [HT3] increased with increasing the concentrations of the inhibitors and decreased with increasing temperature.

A Human Lectin Microarray for Sperm Surface Glycosylation Analysis *

PubMed Central

Sun, Yangyang; Cheng, Li; Gu, Yihua; Xin, Aijie; Wu, Bin; Zhou, Shumin; Guo, Shujuan; Liu, Yin; Diao, Hua; Shi, Huijuan; Wang, Guangyu; Tao, Sheng-ce

2016-01-01

Glycosylation is one of the most abundant and functionally important protein post-translational modifications. As such, technology for efficient glycosylation analysis is in high demand. Lectin microarrays are a powerful tool for such investigations and have been successfully applied for a variety of glycobiological studies. However, most of the current lectin microarrays are primarily constructed from plant lectins, which are not well suited for studies of human glycosylation because of the extreme complexity of human glycans. Herein, we constructed a human lectin microarray with 60 human lectin and lectin-like proteins. All of the lectins and lectin-like proteins were purified from yeast, and most showed binding to human glycans. To demonstrate the applicability of the human lectin microarray, human sperm were probed on the microarray and strong bindings were observed for several lectins, including galectin-1, 7, 8, GalNAc-T6, and ERGIC-53 (LMAN1). These bindings were validated by flow cytometry and fluorescence immunostaining. Further, mass spectrometry analysis showed that galectin-1 binds several membrane-associated proteins including heat shock protein 90. Finally, functional assays showed that binding of galectin-8 could significantly enhance the acrosome reaction within human sperms. To our knowledge, this is the first construction of a human lectin microarray, and we anticipate it will find wide use for a range of human or mammalian studies, alone or in combination with plant lectin microarrays. PMID:27364157

Spindle cell oncocytomas and granular cell tumors of the pituitary are variants of pituicytoma.

PubMed

Mete, Ozgur; Lopes, Maria Beatriz; Asa, Sylvia L

2013-11-01

Pituicytomas are neoplasms that arise from pituicytes, which are specialized glia of the posterior pituitary. Pituicytes have 5 ultrastructural variants: light, dark, granular, ependymal, and oncocytic. Granular cell tumors of the pituitary gland are thought to arise from granular pituicytes. Spindle cell oncocytomas are considered to arise from folliculostellate cells, which are sustentacular cells of the adenohypophysis. Recent data suggest that, whereas pituicytes and all 3 tumor types are positive for TTF-1, folliculostellate cells are negative for TTF-1. We investigated 7 spindle cell oncocytomas, 4 pituicytomas, and 3 granular cell tumors for their genetic (BRAF(V600E) mutation and BRAF-KIAA fusion), immunohistochemical (GFAP, vimentin, S100 protein, olig2, IDH1-R132H, NF, galectin-3, chromogranin-A, CD56, EMA, CAM5.2, CD68, TTF-1, and bcl-2), and ultrastructural features to refine their classification. All tumors had nuclear positivity for TTF-1 and were negative for CAM5.2, chromogranin-A, and NF. GFAP, vimentin, S100, galectin-3, EMA, and CD68 were variably positive in the majority of the 3 tumor groups. Olig2 was only positive in 1 pituicytoma. Whereas granular cell tumors were negative for bcl-2 and CD56, pituicytomas and spindle cell oncocytomas showed variable positivity. All tumors were negative with the IDH1-R132H mutation-specific antibody, and none had evidence of BRAF alterations (BRAF(V600E) mutation and BRAF-KIAA fusion). Diffuse TTF-1 expression in nontumorous pituicytes, pituicytomas, spindle cell oncocytomas, and granular cell tumors indicates a common pituicyte lineage. The ultrastructural variants of pituicytes are reflected in these 3 morphologic variants of tumors arising from these cells. We propose the terminology "oncocytic pituicytomas" and "granular cell pituicytomas" to refine the classification of these lesions.

Circulating Galectin-3 Levels Are Persistently Elevated After Heart Transplantation and Are Associated With Renal Dysfunction.

PubMed

Grupper, Avishay; Nativi-Nicolau, Jose; Maleszewski, Joseph J; Geske, Jennifer R; Kremers, Walter K; Edwards, Brooks S; Kushwaha, Sudhir S; Pereira, Naveen L

2016-11-01

This study evaluated changes in serum levels of galectin (Gal)-3 before and after heart transplantation (HTx) and assessed the role of pre-HTx Gal-3 as a biomarker for post-HTx outcomes. Gal-3 is a novel biomarker that reflects cardiac remodeling and fibrosis. Elevated serum Gal-3 levels are associated with poor prognosis in heart failure patients. Whether Gal-3 levels change following HTx and the significance of post-HTx outcomes are unknown. Serum Gal-3 levels were measured in 62 patients at 118 days (Interquartile Range [IQR]: 23 to 798 days) before and 365 days (IQR: 54 to 767 days) post HTx. Cardiac tissue taken during routine post-HTx endomyocardial biopsy was evaluated to assess the correlation between tissue Gal-3 staining and serum Gal-3 levels and with the presence of myocardial hypertrophy and fibrosis. Serum Gal-3 levels remained significantly elevated (>17.8 ng/ml) in 35 patients (56%) post HTx. There was a significant inverse correlation between Gal-3 levels and glomerular filtration rate measured before and after HTx (p > 0.005). There was no association between Gal-3 serum level and Gal-3 staining of myocardial tissue or with the presence of myocyte hypertrophy and interstitial fibrosis post HTx. Elevated pre-HTx Gal-3 levels were associated with reduced post-HTx exercise capacity, but this association was not significant after adjustment for age, body mass index, and glomerular filtration rate. This is the first study to demonstrate the fact that Gal-3 levels remain elevated in the majority of patients despite HTx and is associated with renal dysfunction. Our findings suggest Gal-3 is a systemic rather than cardiac-specific biomarker. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Three newly identified galectin homologues from triangle sail mussel (Hyriopsis cumingii) function as potential pattern-recognition receptors.

PubMed

Zhao, Ling-Ling; Hui, Kaimin; Wang, Yu-Qing; Wang, Yue; Ren, Qian; Li, Xin-Cang

2018-05-01

Galactoside-binding lectins, also known as galectins, play crucial roles in innate immune response in invertebrates. In this study, three cDNA sequences from Hyriopsis cumingii were identified and collectively called HcGalec genes. Each of the three deduced HcGalec proteins contained a galactose-binding lectin domain or a GLECT domain. All the three HcGalec genes are mainly present in the hepatopancreas and gills, and their expression is induced at 24 h after bacterial challenge. Three recombinant HcGalec proteins can bind and agglutinate (Ca 2+ -dependent) various microorganisms, including Gram-positive and Gram-negative bacteria. These proteins can attach to mannan and peptidoglycan. Meanwhile, the expression of the three HcGalec genes in the gills were significantly down-regulated after dsRNA interference (HcGalec1-RNAi, HcGalec2-RNAi, and HcGalec3-RNAi) and Vibrio parahaemolyticus injection. The expression levels of some antimicrobial peptides, including lysozyme 1 and lysozyme 2, were also markedly decreased after dsRNA interference. Overall, these results suggested that these three HcGalec proteins may function as potential receptors participating in the innate immune responses of H. cumingii against bacterial infection. Copyright © 2018 Elsevier Ltd. All rights reserved.

Expanded potential of seleno-carbohydrates as a molecular tool for X-ray structural determination of a carbohydrate-protein complex with single/multi-wavelength anomalous dispersion phasing.

PubMed

Suzuki, Tatsuya; Makyio, Hisayoshi; Ando, Hiromune; Komura, Naoko; Menjo, Masanori; Yamada, Yusuke; Imamura, Akihiro; Ishida, Hideharu; Wakatsuki, Soichi; Kato, Ryuichi; Kiso, Makoto

2014-04-01

Seleno-lactoses have been successfully synthesized as candidates for mimicking carbohydrate ligands for human galectin-9 N-terminal carbohydrate recognition domain (NCRD). Selenium was introduced into the mono- or di-saccharides using p-methylselenobenzoic anhydride (Tol2Se) as a novel selenating reagent. The TolSe-substituted monosaccharides were converted into selenoglycosyl donors or acceptors, which were reacted with coupling partners to afford seleno-lactoses. The seleno-lactoses were converted to the target compounds. The structure of human galectin-9 NCRD co-crystallized with 6-MeSe-lactose was determined with single/multi-wavelength anomalous dispersion (SAD/MAD) phasing and was similar to that of the co-crystal with natural lactose. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structural Basis for Carbohydrate Recognition and Anti-inflammatory Modulation by Gastrointestinal Nematode Parasite Toxascaris leonina Galectin*

PubMed Central

Hwang, Eun Young; Jeong, Mi Suk; Park, Sang Kyun; Ha, Sung Chul; Yu, Hak Sun; Jang, Se Bok

2016-01-01

Toxascaris leonina galectin (Tl-gal) is a galectin-9 homologue protein isolated from an adult worm of the canine gastrointestinal nematode parasite, and Tl-gal-vaccinated challenge can inhibit inflammation in inflammatory bowel disease-induced mice. We determined the first X-ray structures of full-length Tl-gal complexes with carbohydrates (lactose, N-acetyllactosamine, lacto-N-tetraose, sialyllactose, and glucose). Bonds were formed on concave surfaces of both carbohydrate recognition domains (CRDs) in Tl-gal. All binding sites were found in the HXXXR and WGXEER motifs. Charged Arg61/Arg196 and Glu80/Glu215 on the conserved motif of Tl-gal N-terminal CRD and C-terminal CRD are critical amino acids for recognizing carbohydrate binding, and the residues can affect protein folding and structure. The polar amino acids His, Asn, and Trp are also important residues for the interaction with carbohydrates through hydrogen bonding. Hemagglutination activities of Tl-gal were inhibited by interactions with carbohydrates and mutations. We found that the mutation of Tl-gal (E80A/E215A) at the carbohydrate binding region induced protein aggregation and could be caused in many diseases. The short linker region between the N-terminal and C-terminal CRDs of Tl-gal was very stable against proteolysis and maintained its biological activity. This structural information is expected to elucidate the carbohydrate recognition mechanism of Tl-gal and improve our understanding of anti-inflammatory mediators and modulators of immune response. PMID:27742836

Pim kinase inhibition sensitizes FLT3-ITD acute myeloid leukemia cells to topoisomerase 2 inhibitors through increased DNA damage and oxidative stress

PubMed Central

Doshi, Kshama A.; Trotta, Rossana; Natarajan, Karthika; Rassool, Feyruz V.; Tron, Adriana E.; Huszar, Dennis; Perrotti, Danilo; Baer, Maria R.

2016-01-01

Internal tandem duplication of fms-like tyrosine kinase-3 (FLT3-ITD) is frequent (30 percent) in acute myeloid leukemia (AML), and is associated with short disease-free survival following chemotherapy. The serine threonine kinase Pim-1 is a pro-survival oncogene transcriptionally upregulated by FLT3-ITD that also promotes its signaling in a positive feedback loop. Thus inhibiting Pim-1 represents an attractive approach in targeting FLT3-ITD cells. Indeed, co-treatment with the pan-Pim kinase inhibitor AZD1208 or expression of a kinase-dead Pim-1 mutant sensitized FLT3-ITD cell lines to apoptosis triggered by chemotherapy drugs including the topoisomerase 2 inhibitors daunorubicin, etoposide and mitoxantrone, but not the nucleoside analog cytarabine. AZD1208 sensitized primary AML cells with FLT3-ITD to topoisomerase 2 inhibitors, but did not sensitize AML cells with wild-type FLT3 or remission bone marrow cells, supporting a favorable therapeutic index. Mechanistically, the enhanced apoptosis observed with AZD1208 and topoisomerase 2 inhibitor combination treatment was associated with increased DNA double-strand breaks and increased levels of reactive oxygen species (ROS), and co-treatment with the ROS scavenger N-acetyl cysteine rescued FLT3-ITD cells from AZD1208 sensitization to topoisomerase 2 inhibitors. Our data support testing of Pim kinase inhibitors with topoisomerase 2 inhibitors, but not with cytarabine, to improve treatment outcomes in AML with FLT3-ITD. PMID:27374090

Galectin-9 Expression Predicts Favorable Clinical Outcome in Solid Tumors: A Systematic Review and Meta-Analysis

PubMed Central

Zhou, Xiaoxiang; Sun, Lejia; Jing, Dan; Xu, Gang; Zhang, Jinmei; Lin, Li; Zhao, Jingjing; Yao, Zhuoran; Lin, Hongfeng

2018-01-01

Background and Objective: Galectin-9 (Gal-9) is one of the galectin family members which are known as proteins with β-galactoside-binding affinity. Accumulative evidence suggest that Gal-9 plays multifaceted roles in tumor biology. However, the prognostic significance of Gal-9 in solid cancer patients remains controversial. The objective of the study was to clarify the prognostic significance of Gal-9 in solid tumors via meta-analysis. Methods: We searched PubMed, Embase and the Cochrane library for studies that report the correlation between Gal-9 expression and prognosis or clinicopathological parameters in solid cancer patients from inception to October 2017, with no language restriction. We calculated pooled hazard ratio (HR) and 95% confidence interval (CI) to investigate the prognostic significance of Gal-9 expression in solid tumors. We also calculated Odds ratio (OR) to explore the association between Gal-9 expression and clinicopathological features. Results: We included Fourteen studies with 2326 patients in our meta-analysis. The synthetic results revealed that high Gal-9 expression indicated improved overall survival (OS; HR = 0.70, 95% CI = 0.51–0.71, P = 0.006) but had no correlation with disease-free survival (DFS)/recurrence-free survival (RFS) (HR = 0.85, 95% CI = 0.51–1.41, P = 0.527) in solid tumors. In stratified analyses, high Gal-9 expression was significantly correlated with improved OS in hepatocellular carcinoma and colon cancer and with improved DFS/RFS in gastric cancer and non-small cell lung cancer. In addition, ethnicity and the method of data extraction didn’t affect the positive prognostic values of high Gal-9 expression. Moreover, high Gal-9 expression was significantly correlated with a smaller depth of invasion (TI/TII vs. TIII/TIV, OR = 2.80, 95% CI = 1.97–3.96, P < 0.001), an earlier histopathological stage (I/II vs. III/IV, OR = 3.00, 95% CI = 2.04–4.42, P < 0.001), negative lymph node metastasis (Presence vs. Absence, OR = 0.47, 95% CI = 0.25–0.89, P = 0.020) and negative distal tumor metastasis (Presence vs. Absence, OR = 13.85, 95% CI = 3.50–54.76, P < 0.001). Conclusion: Gal-9 expression indicates beneficial outcome in patients with solid tumors and is correlated with the pathogenesis of solid tumors. Gal-9 may serve as a prognostic biomarker and an emerging therapeutic target against solid tumors. PMID:29765332

Galectin-9 Expression Predicts Favorable Clinical Outcome in Solid Tumors: A Systematic Review and Meta-Analysis.

PubMed

Zhou, Xiaoxiang; Sun, Lejia; Jing, Dan; Xu, Gang; Zhang, Jinmei; Lin, Li; Zhao, Jingjing; Yao, Zhuoran; Lin, Hongfeng

2018-01-01

Background and Objective: Galectin-9 (Gal-9) is one of the galectin family members which are known as proteins with β-galactoside-binding affinity. Accumulative evidence suggest that Gal-9 plays multifaceted roles in tumor biology. However, the prognostic significance of Gal-9 in solid cancer patients remains controversial. The objective of the study was to clarify the prognostic significance of Gal-9 in solid tumors via meta-analysis. Methods: We searched PubMed, Embase and the Cochrane library for studies that report the correlation between Gal-9 expression and prognosis or clinicopathological parameters in solid cancer patients from inception to October 2017, with no language restriction. We calculated pooled hazard ratio (HR) and 95% confidence interval (CI) to investigate the prognostic significance of Gal-9 expression in solid tumors. We also calculated Odds ratio (OR) to explore the association between Gal-9 expression and clinicopathological features. Results: We included Fourteen studies with 2326 patients in our meta-analysis. The synthetic results revealed that high Gal-9 expression indicated improved overall survival (OS; HR = 0.70, 95% CI = 0.51-0.71, P = 0.006) but had no correlation with disease-free survival (DFS)/recurrence-free survival (RFS) (HR = 0.85, 95% CI = 0.51-1.41, P = 0.527) in solid tumors. In stratified analyses, high Gal-9 expression was significantly correlated with improved OS in hepatocellular carcinoma and colon cancer and with improved DFS/RFS in gastric cancer and non-small cell lung cancer. In addition, ethnicity and the method of data extraction didn't affect the positive prognostic values of high Gal-9 expression. Moreover, high Gal-9 expression was significantly correlated with a smaller depth of invasion (TI/TII vs. TIII/TIV, OR = 2.80, 95% CI = 1.97-3.96, P < 0.001), an earlier histopathological stage (I/II vs. III/IV, OR = 3.00, 95% CI = 2.04-4.42, P < 0.001), negative lymph node metastasis (Presence vs. Absence, OR = 0.47, 95% CI = 0.25-0.89, P = 0.020) and negative distal tumor metastasis (Presence vs. Absence, OR = 13.85, 95% CI = 3.50-54.76, P < 0.001). Conclusion: Gal-9 expression indicates beneficial outcome in patients with solid tumors and is correlated with the pathogenesis of solid tumors. Gal-9 may serve as a prognostic biomarker and an emerging therapeutic target against solid tumors.

Galectin-1 drives pancreatic carcinogenesis through stroma remodeling and Hedgehog signaling activation

PubMed Central

Martínez-Bosch, Neus; Fernández-Barrena, Maite G.; Moreno, Mireia; Ortiz-Zapater, Elena; André, Sabine; Gabius, Hans-Joachim; Hwang, Rosa F.; Poirier, Françoise; Munné-Collado, Jessica; Iglesias, Mar; Navas, Carolina; Guerra, Carmen; Fernández-Zapico, Martin E.; Navarro, Pilar

2015-01-01

Pancreatic ductal adenocarcinoma (PDA) is the most aggressive tumor, showing incidence and mortality values almost identical. Despite remarkable advances in PDA molecular characterization, this disease is still refractory to current treatments. Desmoplastic stroma, a constant hallmark of PDA, has recently emerged as the major responsible for PDA therapeutic resistance, therefore representing a promising target. Galectin-1 (Gal1), a glycan-binding protein, is highly expressed in PDA stroma but its role remains unknown. Here, we aim to understand in vivo Gal1 functions and the molecular pathways responsible for its oncogenic properties. Genetic ablation of Gal1 in Ela-myc mice dampens tumor progression through inhibition of proliferation, angiogenesis, desmoplasia and stimulation of tumor-associated immune response, resulting in a 20% increase on the animal life span. In vitro and in vivo studies unveil that these effects are mediated by modulation of the tumor microenvironment in a non-cell autonomous manner. Importantly, acinar-to-ductal metaplasia, a crucial step for PDA initiation, is also regulated by Gal1. Finally, high-throughput gene expression studies and molecular analysis aimed at identifying the underlying mechanism revealed that Gal1 promotes Hedgehog pathway both in PDA cells and stromal fibroblasts. In summary, our studies define a novel role of Gal1 in PDA tumor epithelium-stroma crosstalk and suggest this lectin as potential molecular target for therapy of neoplasms overexpressing Gal1. PMID:24812270

Off-Target Vascular Effects of Cholesteryl Ester Transfer Protein Inhibitors Involve Redox-Sensitive and Signal Transducer and Activator of Transcription 3-Dependent Pathways.

PubMed

Rios, Francisco J; Lopes, Rheure A; Neves, Karla B; Camargo, Livia L; Montezano, Augusto C; Touyz, Rhian M

2016-05-01

Elevated blood pressure was an unexpected outcome in some cholesteryl ester transfer protein (CETP) inhibitor trials, possibly due to vascular effects of these drugs. We investigated whether CETP inhibitors (torcetrapib, dalcetrapib, anacetrapib) influence vascular function and explored the putative underlying molecular mechanisms. Resistance arteries and vascular smooth muscle cells (VSMC) from rats, which lack the CETP gene, were studied. CETP inhibitors increased phenylephrine-stimulated vascular contraction (logEC50 (:) 6.6 ± 0.1; 6.4 ± 0.06, and 6.2 ± 0.09 for torcetrapib, dalcetrapib, and anacetrapib, respectively, versus control 5.9 ± 0.05). Only torcetrapib reduced endothelium-dependent vasorelaxation. The CETP inhibitor effects were ameliorated by N-acetylcysteine (NAC), a reactive oxygen species (ROS) scavenger, and by S3I-201 [2-hydroxy-4-[[2-(4-methylphenyl)sulfonyloxyacetyl]amino]benzoic acid], a signal transducer and activator of transcription 3 (STAT3) inhibitor. CETP inhibitors increased the phosphorylation (2- to 3-fold) of vascular myosin light chain (MLC) and myosin phosphatase target subunit 1 (MYPT1) (procontractile proteins) and stimulated ROS production. CETP inhibitors increased the phosphorylation of STAT3 (by 3- to 4-fold), a transcription factor important in cell activation. Activation of MLC was reduced by NAC, GKT137831 [2-(2-chlorophenyl)-4-[3-(dimethylamino)phenyl]-5-methyl-1H-pyrazolo[4,3-c]pyridine-3,6-dione] (Nox1/4 inhibitor), and S3I-201. The phosphorylation of STAT3 was unaffected by NAC and GKT137831. CETP inhibitors did not influence activation of mitogen-activated proteins kinases (MAPK) or c-Src. Our data demonstrate that CETP inhibitors influence vascular function and contraction through redox-sensitive, STAT3-dependent, and MAPK-independent processes. These phenomena do not involve CETP because the CETP gene is absent in rodents. Findings from our study indicate that CETP inhibitors have vasoactive properties, which may contribute to the adverse cardiovascular effects of these drugs such as hypertension. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Quantitative Glycoproteomics Analysis Reveals Changes in N-Glycosylation Level Associated with Pancreatic Ductal Adenocarcinoma

PubMed Central

2015-01-01

Glycosylation plays an important role in epithelial cancers, including pancreatic ductal adenocarcinoma. However, little is known about the glycoproteome of the human pancreas or its alterations associated with pancreatic tumorigenesis. Using quantitative glycoproteomics approach, we investigated protein N-glycosylation in pancreatic tumor tissue in comparison with normal pancreas and chronic pancreatitis tissue. The study lead to the discovery of a roster of glycoproteins with aberrant N-glycosylation level associated with pancreatic cancer, including mucin-5AC (MUC5AC), carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), insulin-like growth factor binding protein (IGFBP3), and galectin-3-binding protein (LGALS3BP). Pathway analysis of cancer-associated aberrant glycoproteins revealed an emerging phenomenon that increased activity of N-glycosylation was implicated in several pancreatic cancer pathways, including TGF-β, TNF, NF-kappa-B, and TFEB-related lysosomal changes. In addition, the study provided evidence that specific N-glycosylation sites within certain individual proteins can have significantly altered glycosylation occupancy in pancreatic cancer, reflecting the complexity of the molecular mechanisms underlying cancer-associated glycosylation events. PMID:24471499

Quantitative glycoproteomics analysis reveals changes in N-glycosylation level associated with pancreatic ductal adenocarcinoma.

PubMed

Pan, Sheng; Chen, Ru; Tamura, Yasuko; Crispin, David A; Lai, Lisa A; May, Damon H; McIntosh, Martin W; Goodlett, David R; Brentnall, Teresa A

2014-03-07

Glycosylation plays an important role in epithelial cancers, including pancreatic ductal adenocarcinoma. However, little is known about the glycoproteome of the human pancreas or its alterations associated with pancreatic tumorigenesis. Using quantitative glycoproteomics approach, we investigated protein N-glycosylation in pancreatic tumor tissue in comparison with normal pancreas and chronic pancreatitis tissue. The study lead to the discovery of a roster of glycoproteins with aberrant N-glycosylation level associated with pancreatic cancer, including mucin-5AC (MUC5AC), carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), insulin-like growth factor binding protein (IGFBP3), and galectin-3-binding protein (LGALS3BP). Pathway analysis of cancer-associated aberrant glycoproteins revealed an emerging phenomenon that increased activity of N-glycosylation was implicated in several pancreatic cancer pathways, including TGF-β, TNF, NF-kappa-B, and TFEB-related lysosomal changes. In addition, the study provided evidence that specific N-glycosylation sites within certain individual proteins can have significantly altered glycosylation occupancy in pancreatic cancer, reflecting the complexity of the molecular mechanisms underlying cancer-associated glycosylation events.

Perspectives on the Trypanosoma cruzi–host cell receptor interactions

PubMed Central

Villalta, Fernando; Scharfstein, Julio; Ashton, Anthony W.; Tyler, Kevin M.; Guan, Fangxia; Mukherjee, Shankar; Lima, Maria F.; Alvarez, Sandra; Weiss, Louis M.; Huang, Huan; Machado, Fabiana S.

2009-01-01

Chagas disease is caused by the parasite Trypanosoma cruzi. The critical initial event is the interaction of the trypomastigote form of the parasite with host receptors. This review highlights recent observations concerning these interactions. Some of the key receptors considered are those for thromboxane, bradykinin, and for the nerve growth factor TrKA. Other important receptors such as galectin-3, thrombospondin, and laminin are also discussed. Investigation into the molecular biology and cell biology of host receptors for T. cruzi may provide novel therapeutic targets. PMID:19283409

Curcumin Derivatives as Green Corrosion Inhibitors for α-Brass in Nitric Acid Solution

NASA Astrophysics Data System (ADS)

Fouda, A. S.; Elattar, K. M.

2012-11-01

1,7- Bis-(4-hydroxy-3-methoxy-phenyl)-hepta-1,6-diene-4-arylazo-3,5-dione I-V have been investigated as corrosion inhibitors for α-brass in 2 M nitric acid solution using weight-loss and galvanostatic polarization techniques. The efficiency of the inhibitors increases with the increase in the inhibitor concentration but decreases with a rise in temperature. The conjoint effect of the curcumin derivatives and KSCN has also been studied. The apparent activation energy ( E a*) and other thermodynamic parameters for the corrosion process have also been calculated. The galvanostatic polarization data indicated that the inhibitors were of mixed-type, but the cathode is more polarized than the anode. The slopes of the cathodic and anodic Tafel lines ( b c and b a) are maintained approximately equal for various inhibitor concentrations. However, the value of the Tafel slopes increases together as inhibitor concentration increases. The adsorption of these compounds on α-brass surface has been found to obey the Frumkin's adsorption isotherm. The mechanism of inhibition was discussed in the light of the chemical structure of the undertaken inhibitors.

A PI3K p110α-selective inhibitor enhances the efficacy of anti-HER2/neu antibody therapy against breast cancer in mice.

PubMed

Choi, Jae-Hyeog; Kim, Ki Hyang; Roh, Kug-Hwan; Jung, Hana; Lee, Anbok; Lee, Ji-Young; Song, Joo Yeon; Park, Seung Jae; Kim, Ilhwan; Lee, Won-Sik; Seo, Su-Kil; Choi, Il-Whan; Fu, Yang-Xin; Yea, Sung Su; Park, SaeGwang

2018-01-01

Combination therapies with phosphoinositide 3-kinase (PI3K) inhibitors and trastuzumab (anti-human epidermal growth factor receptor [HER]2/neu antibody) are effective against HER2+ breast cancer. Isoform-selective PI3K inhibitors elicit anti-tumor immune responses that are distinct from those induced by inhibitors of class I PI3K isoforms (pan-PI3K inhibitors). The present study investigated the therapeutic effect and potential for stimulating anti-tumor immunity of combined therapy with an anti-HER2/neu antibody and pan-PI3K inhibitor (GDC-0941) or a PI3K p110α isoform-selective inhibitor (A66) in mouse models of breast cancer. The anti-neu antibody inhibited tumor growth and enhanced anti-tumor immunity in HER2/neu+ breast cancer TUBO models, whereas GDC-0941 or A66 alone did not. Anti-neu antibody and PI3K inhibitor synergistically promoted anti-tumor immunity by increasing functional T cell production. In the presence of the anti-neu antibody, A66 was more effective than GDC-0941 at increasing the fraction of CD4 + , CD8 + , and IFN-γ + CD8 + T cells in the tumor-infiltrating lymphocyte population. Detection of IFN-γ levels by enzyme-linked immunospot assay showed that the numbers of tumor-specific T cells against neu and non-neu tumor antigens were increased by combined PI3K inhibitor plus anti-neu antibody treatment, with A66 exhibiting more potent effects than GDC-0941. In a TUBO (neu+) and TUBO-P2J (neu-) mixed tumor model representing immunohistochemistry 2+ tumors, A66 suppressed tumor growth and prolonged survival to a greater extent than GDC-0941 when combined with anti-neu antibody. These results demonstrate that a PI3K p110α-isoform-selective inhibitor is an effective adjunct to trastuzumab in the treatment of HER2-positive breast cancer.

Induction of autophagy by PI3K/MTOR and PI3K/MTOR/BRD4 inhibitors suppresses HIV-1 replication.

PubMed

Campbell, Grant R; Bruckman, Rachel S; Herns, Shayna D; Joshi, Shweta; Durden, Donald L; Spector, Stephen A

2018-04-20

In this study, we investigated the effects of the dual phosphatidylinositol 3-kinase/mechanistic target of rapamycin (PI3K/MTOR) inhibitor dactolisib (NVP-BEZ235), the PI3K/MTOR/bromodomain-containing protein 4 (BRD4) inhibitor SF2523, and the bromodomain and extra terminal domain inhibitor JQ1 on the productive infection of primary macrophages with human immunodeficiency type-1 (HIV). These inhibitors did not alter the initial susceptibility of macrophages to HIV infection. However, dactolisib, JQ1, and SF2523 all decreased HIV replication in macrophages in a dose-dependent manner via degradation of intracellular HIV through autophagy. Macrophages treated with dactolisib, JQ1, or SF2523 displayed an increase in LC3B lipidation combined with SQSTM1 degradation without inducing increased cell death. LC3B-II levels were further increased in the presence of pepstatin A suggesting that these inhibitors induce autophagic flux. RNA interference for ATG5 and ATG7 and pharmacological inhibitors of autophagosome-lysosome fusion and of lysosomal hydrolases all blocked the inhibition of HIV. Thus, we demonstrate that the mechanism of PI3K/MTOR and PI3K/MTOR/BRD4 inhibitor suppression of HIV requires the formation of autophagosomes, as well as their subsequent maturation into autolysosomes. These data provide further evidence in support of a role for autophagy in the control of HIV infection and open new avenues for the use of this class of drugs in HIV therapy. © 2018 Campbell et al.

Silencing of CD40 in vivo reduces progression of experimental atherogenesis through an NF-κB/miR-125b axis and reveals new potential mediators in the pathogenesis of atherosclerosis.

PubMed

Hueso, Miguel; De Ramon, Laura; Navarro, Estanislao; Ripoll, Elia; Cruzado, Josep M; Grinyo, Josep M; Torras, Joan

2016-12-01

CD40/CD40L signaling exerts a critical role in the development of atherosclerosis, and microRNAs (miRNAs) are key regulators in vascular inflammation and plaque formation. In this work, we investigated mRNA/miRNA expression during progression of atherosclerotic lesions through CD40 silencing. We silenced CD40 with a specific siRNA in ApoE -/- mice and compared expression of mRNA/miRNA in ascending aorta with scrambled treated mice. siRNA-CD40 treated mice significantly reduced the extension and severity of atherosclerotic lesions, as well as the number of F4/80 + , galectin-3 + macrophages and NF-κB + cells in the intima. Genome-wide mRNA/miRNA profiling allowed the identification of transcripts, which were significantly upregulated during atherosclerosis; among them, miR-125b and miR-30a, Xpr1, a regulator of macrophage differentiation, Taf3, a core transcription factor and the NF-κB activator Ikkβ, whereas, the NF-κB inhibitor Ikbα was downregulated during disease progression. All those changes were reversed upon CD40 silencing. Interestingly, TAF3, XPR1 and miR-125b were also overexpressed in human atherosclerotic plaques. Murine Taf3 and Xpr1 were detected in the perivascular adipose tissue (PVAT), and Taf3 also in intimal foam cells. Finally, expression of miR-125b was regulated by the CD40-NF-κB signaling axis in RAW264.7 macrophages. CD40 silencing with a specific siRNA ameliorates progression of experimental atherosclerosis in ApoE -/- mice, and evidences a role for NF-κB, Taf3, Xpr1, and miR-125b in the pathogenesis of atherosclerosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Identification of Galectin-1 as a Critical Factor in Function of Mouse Mesenchymal Stromal Cell-Mediated Tumor Promotion

PubMed Central

Blazsó, Péter; Katona, Róbert László; Novák, Julianna; Szabó, Enikő; Czibula, Ágnes; Fajka-Boja, Roberta; Hegyi, Beáta; Uher, Ferenc; Krenács, László; Joó, Gabriella; Monostori, Éva

2012-01-01

Bone marrow derived mesenchymal stromal cells (MSCs) have recently been implicated as one source of the tumor-associated stroma, which plays essential role in regulating tumor progression. In spite of the intensive research, the individual factors in MSCs controlling tumor progression have not been adequately defined. In the present study we have examined the role of galectin-1 (Gal-1), a protein highly expressed in tumors with poor prognosis, in MSCs in the course of tumor development. Co-transplantation of wild type MSCs with 4T1 mouse breast carcinoma cells enhances the incidence of palpable tumors, growth, vascularization and metastasis. It also reduces survival compared to animals treated with tumor cells alone or in combination with Gal-1 knockout MSCs. In vitro studies show that the absence of Gal-1 in MSCs does not affect the number of migrating MSCs toward the tumor cells, which is supported by the in vivo migration of intravenously injected MSCs into the tumor. Moreover, differentiation of endothelial cells into blood vessel-like structures strongly depends on the expression of Gal-1 in MSCs. Vital role of Gal-1 in MSCs has been further verified in Gal-1 knockout mice. By administering B16F10 melanoma cells into Gal-1 deficient animals, tumor growth is highly reduced compared to wild type animals. Nevertheless, co-injection of wild type but not Gal-1 deficient MSCs results in dramatic tumor growth and development. These results confirm that galectin-1 is one of the critical factors in MSCs regulating tumor progression. PMID:22844466

Chicken galectin-1B inhibits Newcastle disease virus adsorption and replication through binding to hemagglutinin-neuraminidase (HN) glycoprotein.

PubMed

Sun, Junfeng; Han, Zongxi; Qi, Tianming; Zhao, Ran; Liu, Shengwang

2017-12-08

Galectin-1 is an important immunoregulatory factor and can mediate the host-pathogen interaction via binding glycans on the surface of various viruses. We previously reported that avian respiratory viruses, including lentogenic Newcastle disease virus (NDV), can induce up-regulation of chicken galectin (CG)-1B in the primary target organ. In this study, we investigated whether CG-1B participated in the infectious process of NDV in chickens. We demonstrated that velogenic NDV induced up-regulation of CG-1B in target organs. We also found that CG-1B directly bound to NDV virions and inhibited their hemagglutination activity in vitro We confirmed that CG-1B interacted with NDV hemagglutinin-neuraminidase (HN) glycoprotein, in which the specific G4 N -glycans significantly contributed to the interaction between CG-1B and HN glycoprotein. The presence of extracellular CG-1B, rather than the internalization process, inhibited adsorption of NDV. The interaction between intracellular CG-1B and NDV HN glycoproteins inhibited cell-surface expression of HN glycoprotein and reduced the titer of progeny virus in NDV-infected DF-1 cells. Significantly, the replication of parental and HN glycosylation mutant viruses in CG-1B knockdown and overexpression cells demonstrated that the replication of NDV was correlated with the expression of CG-1B in a specific glycan-dependent manner. Collectively, our results indicate that CG-1B has anti-NDV activity by binding to N -glycans on HN glycoprotein. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Structural Basis for Carbohydrate Recognition and Anti-inflammatory Modulation by Gastrointestinal Nematode Parasite Toxascaris leonina Galectin.

PubMed

Hwang, Eun Young; Jeong, Mi Suk; Park, Sang Kyun; Ha, Sung Chul; Yu, Hak Sun; Jang, Se Bok

2016-12-02

Toxascaris leonina galectin (Tl-gal) is a galectin-9 homologue protein isolated from an adult worm of the canine gastrointestinal nematode parasite, and Tl-gal-vaccinated challenge can inhibit inflammation in inflammatory bowel disease-induced mice. We determined the first X-ray structures of full-length Tl-gal complexes with carbohydrates (lactose, N-acetyllactosamine, lacto-N-tetraose, sialyllactose, and glucose). Bonds were formed on concave surfaces of both carbohydrate recognition domains (CRDs) in Tl-gal. All binding sites were found in the HXXXR and WGXEER motifs. Charged Arg 61 /Arg 196 and Glu 80 /Glu 215 on the conserved motif of Tl-gal N-terminal CRD and C-terminal CRD are critical amino acids for recognizing carbohydrate binding, and the residues can affect protein folding and structure. The polar amino acids His, Asn, and Trp are also important residues for the interaction with carbohydrates through hydrogen bonding. Hemagglutination activities of Tl-gal were inhibited by interactions with carbohydrates and mutations. We found that the mutation of Tl-gal (E80A/E215A) at the carbohydrate binding region induced protein aggregation and could be caused in many diseases. The short linker region between the N-terminal and C-terminal CRDs of Tl-gal was very stable against proteolysis and maintained its biological activity. This structural information is expected to elucidate the carbohydrate recognition mechanism of Tl-gal and improve our understanding of anti-inflammatory mediators and modulators of immune response. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Modulation of thyroidal radioiodide uptake by oncological pipeline inhibitors and Apigenin.

PubMed

Lakshmanan, Aparna; Scarberry, Daniel; Green, Jill A; Zhang, Xiaoli; Selmi-Ruby, Samia; Jhiang, Sissy M

2015-10-13

Targeted radioiodine therapy for thyroid cancer is based on selective stimulation of Na+/I- Symporter (NIS)-mediated radioactive iodide uptake (RAIU) in thyroid cells by thyrotropin. Patients with advanced thyroid cancer do not benefit from radioiodine therapy due to reduced or absent NIS expression. To identify inhibitors that can be readily translated into clinical care, we examined oncological pipeline inhibitors targeting Akt, MEK, PI3K, Hsp90 or BRAF in their ability to increase RAIU in thyroid cells expressing BRAFV600E or RET/PTC3 oncogene. Our data showed that (1) PI3K inhibitor GDC-0941 outperformed other inhibitors in RAIU increase mainly by decreasing iodide efflux rate to a great extent; (2) RAIU increase by all inhibitors was extensively reduced by TGF-β, a cytokine secreted in the invasive fronts of thyroid cancers; (3) RAIU reduction by TGF-β was mainly mediated by NIS reduction and could be reversed by Apigenin, a plant-derived flavonoid; and (4) In the presence of TGF-β, GDC-0941 with Apigenin co-treatment had the highest RAIU level in both BRAFV600E expressing cells and RET/PTC3 expressing cells. Taken together, Apigenin may serve as a dietary supplement along with small molecule inhibitors to improve radioiodine therapeutic efficacy on invasive tumor margins thereby minimizing future metastatic events.

AAL exacerbates pro-inflammatory response in macrophages by regulating Mincle/Syk/Card9 signaling along with the Nlrp3 inflammasome assembly

PubMed Central

Zhang, Zhijun; He, Long; Hu, Shuang; Wang, Yi; Lai, Qiaohong; Yang, Ping; Yu, Qilin; Zhang, Shu; Xiong, Fei; Simsekyilmaz, Sakine; Ning, Qin; Li, Jinxiu; Zhang, Dongshan; Zhang, Hongliang; Xiang, Xudong; Zhou, Zhiguang; Sun, Hui; Wang, Cong-Yi

2015-01-01

Previously, we demonstrated that Agrocybe aegerita lectin (AAL), a galectin isolated from edible mushroom Agrocybe aegerita, exerts potent anti-tumor activity, while the mechanisms by which AAL suppresses tumor growth are yet to be elucidated. Here, we conducted studies with focus for its impact on the cecal ligation and puncture (CLP)-induced innate immune response. Administration of AAL significantly exacerbated the severity of CLP-induced septic shock as manifested the increased lethality. AAL promoted inflammatory cytokine production by preferentially regulating macrophage activation and recruitment. Mechanistic studies revealed that AAL likely targets macrophages through receptor Mincle to activate Syk/Card9 signaling, which then couples to the Nlrp3 inflammasome assembly. It was further noted that AAL markedly promotes H3K4 di- and trimethylation, by which it enhances Hmgb1 expression. Specifically, AAL induced macrophages secretion of copious amount of Hmgb1 as manifested the Hmgb1 cytoplasmic translocation along with the detection of extracellular Hmgb1. AAL also stimulated a significant increase for nuclear Hmgb1, which then formed a complex with RelA, and thereby enhancing NF-κB transcriptional activity. Together, our data suggest that AAL may possess important pharmaceutical properties in the regulation of innate immune response. PMID:26692926

Effect of spironolactone on 30-day death and heart failure rehospitalization (from the COACH Study).

PubMed

Maisel, Alan; Xue, Yang; van Veldhuisen, Dirk J; Voors, Adriaan A; Jaarsma, Tiny; Pang, Peter S; Butler, Javed; Pitt, Bertram; Clopton, Paul; de Boer, Rudolf A

2014-09-01

The aim of our study is to investigate the effect of spironolactone on 30-day outcomes in patients with acute heart failure (AHF) and the association between treatment and outcomes stratified by biomarkers. We conducted a secondary analysis of the biomarker substudy of the multicenter COACH (Co-ordinating Study Evaluating Outcomes of Advising and Counseling in Heart Failure) trial involving 534 AHF patients for 30-day mortality and HF rehospitalizations. Spironolactone therapy was initiated and terminated at the discretion of the treating physician; 30-day outcomes were compared between patients who were treated with spironolactone and those who were not. Outcomes with spironolactone therapy were explored based on N-terminal pro-B-type natriuretic peptide, ST2, galectin-3, and creatinine levels. Spironolactone was prescribed to 297 (55.6%) patients at discharge (158 new and 139 continued). There were 19 deaths and 30 HF rehospitalizations among 46 patients by 30 days. Patients discharged on spironolactone had significantly less 30-day event (hazard ratio 0.538, p = 0.039) after adjustment for multiple risk factors. Initiation of spironolactone in patients who were not on spironolactone before admission was associated with a significant reduction in event rate (hazard ratio 0.362, p = 0.027). The survival benefit of spironolactone was more prominent in patient groups with elevations of creatinine, N-terminal pro-B-type natriuretic peptide, ST2, or galectin-3. In conclusion, AHF patients who received spironolactone during hospitalization had significantly fewer 30-day mortality and HF rehospitalizations, especially in high-risk patients. Copyright © 2014 Elsevier Inc. All rights reserved.

Comparison of Monoamine Oxidase Inhibitors in Decreasing Production of the Autotoxic Dopamine Metabolite 3,4-Dihydroxyphenylacetaldehyde in PC12 Cells

PubMed Central

Jinsmaa, Yunden; Sullivan, Patti; Holmes, Courtney; Kopin, Irwin J.; Sharabi, Yehonatan

2016-01-01

According to the catecholaldehyde hypothesis, the toxic dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL) contributes to the loss of nigrostriatal dopaminergic neurons in Parkinson’s disease. Monoamine oxidase-A (MAO-A) catalyzes the conversion of intraneuronal dopamine to DOPAL and may serve as a therapeutic target. The “cheese effect”—paroxysmal hypertension evoked by tyramine-containing foodstuffs—limits clinical use of irreversible MAO-A inhibitors. Combined MAO-A/B inhibition decreases DOPAL production in rat pheochromocytoma PC12 cells, but whether reversible MAO-A inhibitors or MAO-B inhibitors decrease endogenous DOPAL production is unknown. We compared the potencies of MAO inhibitors in attenuating DOPAL production and examined possible secondary effects on dopamine storage, constitutive release, synthesis, and auto-oxidation. Catechol concentrations were measured in cells and medium after incubation with the irreversible MAO-A inhibitor clorgyline, three reversible MAO-A inhibitors, or the MAO-B inhibitors selegiline or rasagiline for 180 minutes. Reversible MAO-A inhibitors were generally ineffective, whereas clorgyline (1 nM), rasagiline (500 nM), and selegiline (500 nM) decreased DOPAL levels in the cells and medium. All three drugs also increased dopamine and norepinephrine, decreased 3,4-dihydroxyphenylalanine, and increased cysteinyl-dopamine concentrations in the medium, suggesting increased vesicular uptake and constitutive release, decreased dopamine synthesis, and increased dopamine spontaneous oxidation. In conclusion, clorgyline, rasagiline, and selegiline decrease production of endogenous DOPAL. At relatively high concentrations, the latter drugs probably lose their selectivity for MAO-B. Possibly offsetting increased formation of potentially toxic oxidation products and decreased formation of DOPAL might account for the failure of large clinical trials of MAO-B inhibitors to demonstrate slowing of neurodegeneration in Parkinson’s disease. PMID:26574516

Effects of application of inhibitors and biochar to fertilizer on gaseous nitrogen emissions from an intensively managed wheat field.

PubMed

He, Tiehu; Liu, Deyan; Yuan, Junji; Luo, Jiafa; Lindsey, Stuart; Bolan, Nanthi; Ding, Weixin

2018-07-01

The effects of biochar combined with the urease inhibitor, hydroquinone, and nitrification inhibitor, dicyandiamide, on gaseous nitrogen (N 2 O, NO and NH 3 ) emissions and wheat yield were examined in a wheat crop cultivated in a rice-wheat rotation system in the Taihu Lake region of China. Eight treatments comprised N fertilizer at a conventional application rate of 150kgNha -1 (CN); N fertilizer at an optimal application rate of 125kgNha -1 (ON); ON+wheat-derived biochar at rates of 7.5 (ONB1) and 15tha -1 (ONB2); ON+nitrification and urease inhibitors (ONI); ONI+wheat-derived biochar at rates of 7.5 (ONIB1) and 15tha -1 (ONIB2); and, a control. The reduced N fertilizer application rate in the ON treatment decreased N 2 O, NO, and NH 3 emissions by 45.7%, 17.1%, and 12.3%, respectively, compared with the CN treatment. Biochar application increased soil organic carbon, total N, and pH, and also increased NH 3 and N 2 O emissions by 32.4-68.2% and 9.4-35.2%, respectively, compared with the ON treatment. In contrast, addition of urease and nitrification inhibitors decreased N 2 O, NO, and NH 3 emissions by 11.3%, 37.9%, and 38.5%, respectively. The combined application of biochar and inhibitors more effectively reduced N 2 O and NO emissions by 49.1-49.7% and 51.7-55.2%, respectively, compared with ON and decreased NH 3 emission by 33.4-35.2% compared with the ONB1 and ONB2 treatments. Compared with the ON treatment, biochar amendment, either alone or in combination with inhibitors, increased wheat yield and N use efficiency (NUE), while addition of inhibitors alone increased NUE but not wheat yield. We suggest that an optimal N fertilizer rate and combined application of inhibitors+biochar at a low application rate, instead of biochar application alone, could increase soil fertility and wheat yields, and mitigate gaseous N emissions. Copyright © 2018 Elsevier B.V. All rights reserved.

Delayed inflammatory mRNA and protein expression after spinal cord injury

PubMed Central

2011-01-01

Background Spinal cord injury (SCI) induces secondary tissue damage that is associated with inflammation. We have previously demonstrated that inflammation-related gene expression after SCI occurs in two waves - an initial cluster that is acutely and transiently up-regulated within 24 hours, and a more delayed cluster that peaks between 72 hours and 7 days. Here we extend the microarray analysis of these gene clusters up to 6 months post-SCI. Methods Adult male rats were subjected to mild, moderate or severe spinal cord contusion injury at T9 using a well-characterized weight-drop model. Tissue from the lesion epicenter was obtained 4 hours, 24 hours, 7 days, 28 days, 3 months or 6 months post-injury and processed for microarray analysis and protein expression. Results Anchor gene analysis using C1qB revealed a cluster of genes that showed elevated expression through 6 months post-injury, including galectin-3, p22PHOX, gp91PHOX, CD53 and progranulin. The expression of these genes occurred primarily in microglia/macrophage cells and was confirmed at the protein level using both immunohistochemistry and western blotting. As p22PHOX and gp91PHOX are components of the NADPH oxidase enzyme, enzymatic activity and its role in SCI were assessed and NADPH oxidase activity was found to be significantly up-regulated through 6 months post-injury. Further, treating rats with the nonspecific, irreversible NADPH oxidase inhibitor diphenylene iodinium (DPI) reduced both lesion volume and expression of chronic gene cluster proteins one month after trauma. Conclusions These data demonstrate that inflammation-related genes are chronically up-regulated after SCI and may contribute to further tissue loss. PMID:21975064

Ozone-Induced Injury and Oxidative Stress in Bronchiolar Epithelium Are Associated with Altered Pulmonary Mechanics

PubMed Central

Sunil, Vasanthi R.

2013-01-01

In these studies, we analyzed the effects of ozone on bronchiolar epithelium. Exposure of rats to ozone (2 ppm, 3h) resulted in rapid (within 3h) and persistent (up to 72h) histological changes in the bronchiolar epithelium, including hypercellularity, loss of cilia, and necrotizing bronchiolitis. Perivascular edema and vascular congestion were also evident, along with a decrease in Clara cell secretory protein in bronchoalveolar lavage, which was maximal 24h post-exposure. Ozone also induced the appearance of 8-hydroxy-2′-deoxyguanosine, Ym1, and heme oxygenase-1 in the bronchiolar epithelium. This was associated with increased expression of cleaved caspase-9 and beclin-1, indicating initiation of apoptosis and autophagy. A rapid and persistent increase in galectin-3, a regulator of epithelial cell apoptosis, was also observed. Following ozone exposure (3–24h), increased expression of cyclooxygenase-2, inducible nitric oxide synthase, and arginase-1 was noted in bronchiolar epithelium. Ozone-induced injury and oxidative stress in bronchiolar epithelium were linked to methacholine-induced alterations in pulmonary mechanics. Thus, significant increases in lung resistance and elastance, along with decreases in lung compliance and end tidal volume, were observed at higher doses of methacholine. This indicates that ozone causes an increase in effective stiffness of the lung as a consequence of changes in the conducting airways. Collectively, these studies demonstrate that bronchiolar epithelium is highly susceptible to injury and oxidative stress induced by acute exposure to ozone; moreover, this is accompanied by altered lung functioning. PMID:23492811

GSK-3β inhibitors suppressed neuroinflammation in rat cortex by activating autophagy in ischemic brain injury.

PubMed

Zhou, Xiaogang; Zhou, Jian; Li, Xilei; Guo, Chang'an; Fang, Taolin; Chen, Zhengrong

2011-07-29

Previous studies have shown that GSK-3β inhibitor could reduce infarct volume after ischemia brain injury. However, the underlying mechanisms of GSK-3β inhibitor involving neuroprotection remain poorly understood. In the present study, we demonstrated that GSK-3β inhibitor suppressed insult-induced neuroinflammation in rat cortex by increasing autophagy activation in ischemic injury. Male rats were subjected to pMCAO (permanent middle cerebral artery occlusion) followed by treating with SB216763, a GSK-3β inhibitor. We found that insult-induced inflammatory response was significantly decreased by intraperitoneal infusion of SB216763 in rat cortex. A higher level of autophagy was also detected after SB216763 treatment. In the cultured primary microglia, SB216763 activated autophagy and suppressed inflammatory response. Importantly, inhibition of autophagy by Beclin1-siRNA increased inflammatory response in the SB216763-treated microglia. These data suggest that GSK-3β inhibitor suppressed neuroinflammation by activating autophagy after ischemic brain injury, thus offering a new target for prevention of ischemic brain injury. Copyright © 2011 Elsevier Inc. All rights reserved.

Synthesis and characterization of a novel organic corrosion inhibitor for mild steel in 1 M hydrochloric acid

NASA Astrophysics Data System (ADS)

Ahmed, Mohammed H. Othman; Al-Amiery, Ahmed A.; Al-Majedy, Yasmin K.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Gaaz, Tayser Sumer

2018-03-01

The synthesis and characterization of a novel organic corrosion inhibitor (4-(3-mercapto-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazin-6-yl)phenol), for mild steel in 1 M hydrochloric acid (HCl) has been successfully reported for the first time. The inhibitor evaluated as corrosion inhibitor for mild steel in 1 M of Hydrochloric acid solution using electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM) measurement techniques. Changes in the impedance parameters suggested an adsorption of the inhibitor onto the mild steel surface, leading to the formation of protective films. The results show that the inhibition efficiencies increased with increasing the concentrations of the inhibitors and decreased with increasing temperature. The maximum inhibition efficiency up to 67% at the maximum concentration 0.5 mM. This shows that those inhibitors are effective in helping to reduce and slowing down the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing an organic inhibitor for the mild steel that can be weakened by increasing the temperature. The adsorption process of the synthesized organic inhibitor depends on its electronic characteristics in addition to steric effects and the nature of metal surface, temperature degree and the varying degrees of surface-site activity. The synthesized inhibitor molecules were absorbed by metal surface and follow Langmuir isotherms.

Modulation of thyroidal radioiodide uptake by oncological pipeline inhibitors and Apigenin

PubMed Central

Lakshmanan, Aparna; Scarberry, Daniel; Green, Jill A.; Zhang, Xiaoli; Selmi-Ruby, Samia; Jhiang, Sissy M.

2015-01-01

Targeted radioiodine therapy for thyroid cancer is based on selective stimulation of Na+/I− Symporter (NIS)-mediated radioactive iodide uptake (RAIU) in thyroid cells by thyrotropin. Patients with advanced thyroid cancer do not benefit from radioiodine therapy due to reduced or absent NIS expression. To identify inhibitors that can be readily translated into clinical care, we examined oncological pipeline inhibitors targeting Akt, MEK, PI3K, Hsp90 or BRAF in their ability to increase RAIU in thyroid cells expressing BRAFV600E or RET/PTC3 oncogene. Our data showed that (1) PI3K inhibitor GDC-0941 outperformed other inhibitors in RAIU increase mainly by decreasing iodide efflux rate to a great extent; (2) RAIU increase by all inhibitors was extensively reduced by TGF-β, a cytokine secreted in the invasive fronts of thyroid cancers; (3) RAIU reduction by TGF-β was mainly mediated by NIS reduction and could be reversed by Apigenin, a plant-derived flavonoid; and (4) In the presence of TGF-β, GDC-0941 with Apigenin co-treatment had the highest RAIU level in both BRAFV600E expressing cells and RET/PTC3 expressing cells. Taken together, Apigenin may serve as a dietary supplement along with small molecule inhibitors to improve radioiodine therapeutic efficacy on invasive tumor margins thereby minimizing future metastatic events. PMID:26397139

Discovery of isatin and 1H-indazol-3-ol derivatives as d-amino acid oxidase (DAAO) inhibitors.

PubMed

Szilágyi, Bence; Kovács, Péter; Ferenczy, György G; Rácz, Anita; Németh, Krisztina; Visy, Júlia; Szabó, Pál; Ilas, Janez; Balogh, György T; Monostory, Katalin; Vincze, István; Tábi, Tamás; Szökő, Éva; Keserű, György M

2018-05-01

d-Amino acid oxidase (DAAO) is a potential target in the treatment of schizophrenia as its inhibition increases brain d-serine level and thus contributes to NMDA receptor activation. Inhibitors of DAAO were sought testing [6+5] type heterocycles and identified isatin derivatives as micromolar DAAO inhibitors. A pharmacophore and structure-activity relationship analysis of isatins and reported DAAO inhibitors led us to investigate 1H-indazol-3-ol derivatives and nanomolar inhibitors were identified. The series was further characterized by pK a and isothermal titration calorimetry measurements. Representative compounds exhibited beneficial properties in in vitro metabolic stability and PAMPA assays. 6-fluoro-1H-indazol-3-ol (37) significantly increased plasma d-serine level in an in vivo study on mice. These results show that the 1H-indazol-3-ol series represents a novel class of DAAO inhibitors with the potential to develop drug candidates. Copyright © 2018 Elsevier Ltd. All rights reserved.

Left atrial volume index in patients with heart failure and severely impaired left ventricular systolic function: the role of established echocardiographic parameters, circulating cystatin C and galectin-3.

PubMed

Zivlas, Christos; Triposkiadis, Filippos; Psarras, Stelios; Giamouzis, Gregory; Skoularigis, Ioannis; Chryssanthopoulos, Stavros; Kapelouzou, Alkistis; Ramcharitar, Steve; Barnes, Edward; Papasteriadis, Evangelos; Cokkinos, Dennis

2017-11-01

Backround: Left atrial (LA) enlargement plays an important role in the development of heart failure (HF) and is a robust prognostic factor. Fibrotic processes have also been advocated to evoke HF through finite signalling proteins. We examined the association of two such proteins, cystatin C (CysC) and galectin-3 (Gal-3), and other clinical, echocardiographic and biochemical parameters with LA volume index (LAVi) in patients with HF with severely impaired left ventricular ejection fraction (LVEF). Severe renal, liver, autoimmune disease and cancer were exclusion criteria. A total of 40 patients with HF (31 men, age 66.6 ± 1.7) with LVEF = 25.4 ± 0.9% were divided into two groups according to the mean LAVi (51.03 ± 2.9 ml/m 2 ) calculated by two-dimensional transthoracic echocardiography. Greater LAVi was positively associated with LV end-diastolic volume ( p = 0.017), LV end-systolic volume ( p = 0.025), mitral regurgitant volume (MRV) ( p = 0.001), right ventricular systolic pressure (RVSP) ( p < 0.001), restrictive diastolic filling pattern ( p = 0.003) and atrial fibrillation ( p = 0.005). Plasma CysC was positively correlated with LAVi ( R 2 = 0.135, p = 0.019) and log-transformed plasma Gal-3 ( R 2 = 0.109, p = 0.042) by simple linear regression analysis. Stepwise multiple linear regression analysis showed that only MRV ( t = 2.236, p = 0.032), CysC ( t = 2.467, p = 0.019) and RVSP ( t = 2.155, p = 0.038) were significant predictors of LAVi. Apart from known determinants of LAVi, circulating CysC and Gal-3 were associated with greater LA dilatation in patients with HF with reduced LVEF. Interestingly, the correlation between these two fibrotic proteins was positive.

Mechanism of Action of 2-Aminobenzamide HDAC Inhibitors in Reversing Gene Silencing in Friedreich’s Ataxia

PubMed Central

Soragni, Elisabetta; Chou, C. James; Rusche, James R.; Gottesfeld, Joel M.

2015-01-01

The genetic defect in Friedreich’s ataxia (FRDA) is the hyperexpansion of a GAA•TTC triplet in the first intron of the FXN gene, encoding the essential mitochondrial protein frataxin. Histone post-translational modifications near the expanded repeats are consistent with heterochromatin formation and consequent FXN gene silencing. Using a newly developed human neuronal cell model, derived from patient-induced pluripotent stem cells, we find that 2-aminobenzamide histone deacetylase (HDAC) inhibitors increase FXN mRNA levels and frataxin protein in FRDA neuronal cells. However, only compounds targeting the class I HDACs 1 and 3 are active in increasing FXN mRNA in these cells. Structural analogs of the active HDAC inhibitors that selectively target either HDAC1 or HDAC3 do not show similar increases in FXN mRNA levels. To understand the mechanism of action of these compounds, we probed the kinetic properties of the active and inactive inhibitors, and found that only compounds that target HDACs 1 and 3 exhibited a slow-on/slow-off mechanism of action for the HDAC enzymes. HDAC1- and HDAC3-selective compounds did not show this activity. Using siRNA methods in the FRDA neuronal cells, we show increases in FXN mRNA upon silencing of either HDACs 1 or 3, suggesting the possibility that inhibition of each of these class I HDACs is necessary for activation of FXN mRNA synthesis, as there appears to be redundancy in the silencing mechanism caused by the GAA•TTC repeats. Moreover, inhibitors must have a long residence time on their target enzymes for this activity. By interrogating microarray data from neuronal cells treated with inhibitors of different specificity, we selected two genes encoding histone macroH2A (H2AFY2) and Polycomb group ring finger 2 (PCGF2) that were specifically down-regulated by the inhibitors targeting HDACs1 and 3 versus the more selective inhibitors for further investigation. Both genes are involved in transcriptional repression and we speculate their involvement in FXN gene silencing. Our results shed light on the mechanism whereby HDAC inhibitors increase FXN mRNA levels in FRDA neuronal cells. PMID:25798128

Conjugated Bilirubin Upregulates TIM-3 Expression on CD4+CD25+ T Cells: Anti-Inflammatory Implications for Hepatitis A Virus Infection.

PubMed

Trujillo-Ochoa, Jorge L; Corral-Jara, Karla F; Charles-Niño, Claudia L; Panduro, Arturo; Fierro, Nora A

2018-04-01

Bilirubin (BR), a metabolite with increased concentrations in plasma during viral hepatitis, has been recognized as a potential immune-modulator. We recently reported that conjugated BR (CB) augments regulatory T cell (Treg) suppressor activity during acute hepatitis A virus (HAV) infection. However, the mechanisms related to the effects of CB on Treg function in the course of hepatotropic viral diseases have not been elucidated. T cell immunoglobulin domain and mucin domain 3 (TIM-3), via its interactions with galectin-9 (GAL-9), is a receptor associated with enhanced Treg function. Thus, TIM-3 expression may be related to the crosstalk between CB and Tregs during HAV infection. Herein, in vitro treatment with high concentrations of CB upregulated TIM-3 expression on Tregs from healthy donors. CB treatment in vitro did not induce de novo Treg generation, and in vitro stimulation with TGF-β, which shows increased secretion during HAV infection, resulted in a trend toward increased TIM-3 expression on Tregs and CD4 + T lymphocytes (TLs) from healthy donors. Interestingly, an upregulation of TIM-3 expression on CD4 + CD25 + T cells and an increase in the proportion of CD4 + TLs expressing GAL-9 were found in HAV-infected patients with abnormal CB values relative to healthy controls. In addition, a statistically significantly reduction in IL-17F production was observed after treatment of CD4 + TLs from healthy donors with high doses of CB in vitro. In summary, our results suggest that CB might regulate Treg activity via a TIM-3-mediated mechanism, ultimately leading to an anti-inflammatory hepatoprotective effect.

Glycosylation-dependent binding of galectin-8 to activated leukocyte cell adhesion molecule (ALCAM/CD166) promotes its surface segregation on breast cancer cells.

PubMed

Fernández, Marisa M; Ferragut, Fátima; Cárdenas Delgado, Víctor M; Bracalente, Candelaria; Bravo, Alicia I; Cagnoni, Alejandro J; Nuñez, Myriam; Morosi, Luciano G; Quinta, Héctor R; Espelt, María V; Troncoso, María F; Wolfenstein-Todel, Carlota; Mariño, Karina V; Malchiodi, Emilio L; Rabinovich, Gabriel A; Elola, María T

2016-10-01

We previously demonstrated that the activated leukocyte cell adhesion molecule (ALCAM/CD166) can interact with galectin-8 (Gal-8) in endothelial cells. ALCAM is a member of the immunoglobulin superfamily that promotes homophilic and heterophilic cell-cell interactions. Gal-8 is a "tandem-repeat"-type galectin, known as a matricellular protein involved in cell adhesion. Here, we analyzed the physical interaction between both molecules in breast cancer cells and the functional relevance of this phenomenon. We performed binding assays by surface plasmon resonance to study the interaction between Gal-8 and the recombinant glycosylated ALCAM ectodomain or endogenous ALCAM from MDA-MB-231 breast cancer cells. We also analyzed the binding of ALCAM-silenced or control breast cancer cells to immobilized Gal-8 by SPR. In internalization assays, we evaluated the influence of Gal-8 on ALCAM surface localization. We showed that recombinant glycosylated ALCAM and endogenous ALCAM from breast carcinoma cells physically interacted with Gal-8 in a glycosylation-dependent fashion displaying a differential behavior compared to non-glycosylated ALCAM. Moreover, ALCAM-silenced breast cancer cells exhibited reduced binding to Gal-8 relative to control cells. Importantly, exogenously added Gal-8 provoked ALCAM segregation, probably trapping this adhesion molecule at the surface of breast cancer cells. Our data indicate that Gal-8 interacts with ALCAM at the surface of breast cancer cells through glycosylation-dependent mechanisms. A novel heterophilic interaction between ALCAM and Gal-8 is demonstrated here, suggesting its physiologic relevance in the biology of breast cancer cells. Copyright © 2016 Elsevier B.V. All rights reserved.

Changes in signal transducer and activator of transcription 3 (STAT3) dynamics induced by complexation with pharmacological inhibitors of Src homology 2 (SH2) domain dimerization.

PubMed

Resetca, Diana; Haftchenary, Sina; Gunning, Patrick T; Wilson, Derek J

2014-11-21

The activity of the transcription factor signal transducer and activator of transcription 3 (STAT3) is dysregulated in a number of hematological and solid malignancies. Development of pharmacological STAT3 Src homology 2 (SH2) domain interaction inhibitors holds great promise for cancer therapy, and a novel class of salicylic acid-based STAT3 dimerization inhibitors that includes orally bioavailable drug candidates has been recently developed. The compounds SF-1-066 and BP-1-102 are predicted to bind to the STAT3 SH2 domain. However, given the highly unstructured and dynamic nature of the SH2 domain, experimental confirmation of this prediction was elusive. We have interrogated the protein-ligand interaction of STAT3 with these small molecule inhibitors by means of time-resolved electrospray ionization hydrogen-deuterium exchange mass spectrometry. Analysis of site-specific evolution of deuterium uptake induced by the complexation of STAT3 with SF-1-066 or BP-1-102 under physiological conditions enabled the mapping of the in silico predicted inhibitor binding site to the STAT3 SH2 domain. The binding of both inhibitors to the SH2 domain resulted in significant local decreases in dynamics, consistent with solvent exclusion at the inhibitor binding site and increased rigidity of the inhibitor-complexed SH2 domain. Interestingly, inhibitor binding induced hot spots of allosteric perturbations outside of the SH2 domain, manifesting mainly as increased deuterium uptake, in regions of STAT3 important for DNA binding and nuclear localization. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Suramin Inhibits Osteoarthritic Cartilage Degradation by Increasing Extracellular Levels of Chondroprotective Tissue Inhibitor of Metalloproteinases 3.

PubMed

Chanalaris, Anastasios; Doherty, Christine; Marsden, Brian D; Bambridge, Gabriel; Wren, Stephen P; Nagase, Hideaki; Troeberg, Linda

2017-10-01

Osteoarthritis is a common degenerative joint disease for which no disease-modifying drugs are currently available. Attempts to treat the disease with small molecule inhibitors of the metalloproteinases that degrade the cartilage matrix have been hampered by a lack of specificity. We aimed to inhibit cartilage degradation by augmenting levels of the endogenous metalloproteinase inhibitor, tissue inhibitor of metalloproteinases (TIMP)-3, through blocking its interaction with the endocytic scavenger receptor, low-density lipoprotein receptor-related protein 1 (LRP1). We discovered that suramin (C 51 H 40 N 6 O 23 S 6 ) bound to TIMP-3 with a K D value of 1.9 ± 0.2 nM and inhibited its endocytosis via LRP1, thus increasing extracellular levels of TIMP-3 and inhibiting cartilage degradation by the TIMP-3 target enzyme, adamalysin-like metalloproteinase with thrombospondin motifs 5. NF279 (8,8'-[carbonyl bis (imino-4,1-phenylenecarbonylimino-4,1-phenylenecarbonylimino)] bis -1,3,5-naphthalenetrisulfonic acid hexasodium salt), a structural analog of suramin, has an increased affinity for TIMP-3 and increased ability to inhibit TIMP-3 endocytosis and protect cartilage. Suramin is thus a promising scaffold for the development of novel therapeutics to increase TIMP-3 levels and inhibit cartilage degradation in osteoarthritis. Copyright © 2017 by The Author(s).

A pivotal role for galectin-1 in fetomaternal tolerance.

PubMed

Blois, Sandra M; Ilarregui, Juan M; Tometten, Mareike; Garcia, Mariana; Orsal, Arif S; Cordo-Russo, Rosalia; Toscano, Marta A; Bianco, Germán A; Kobelt, Peter; Handjiski, Bori; Tirado, Irene; Markert, Udo R; Klapp, Burghard F; Poirier, Francoise; Szekeres-Bartho, Julia; Rabinovich, Gabriel A; Arck, Petra C

2007-12-01

A successful pregnancy requires synchronized adaptation of maternal immune-endocrine mechanisms to the fetus. Here we show that galectin-1 (Gal-1), an immunoregulatory glycan-binding protein, has a pivotal role in conferring fetomaternal tolerance. Consistently with a marked decrease in Gal-1 expression during failing pregnancies, Gal-1-deficient (Lgals1-/-) mice showed higher rates of fetal loss compared to wild-type mice in allogeneic matings, whereas fetal survival was unaffected in syngeneic matings. Treatment with recombinant Gal-1 prevented fetal loss and restored tolerance through multiple mechanisms, including the induction of tolerogenic dendritic cells, which in turn promoted the expansion of interleukin-10 (IL-10)-secreting regulatory T cells in vivo. Accordingly, Gal-1's protective effects were abrogated in mice depleted of regulatory T cells or deficient in IL-10. In addition, we provide evidence for synergy between Gal-1 and progesterone in the maintenance of pregnancy. Thus, Gal-1 is a pivotal regulator of fetomaternal tolerance that has potential therapeutic implications in threatened pregnancies.

Dapagliflozin, a selective SGLT2 Inhibitor, attenuated cardiac fibrosis by regulating the macrophage polarization via STAT3 signaling in infarcted rat hearts.

PubMed

Lee, Tsung-Ming; Chang, Nen-Chung; Lin, Shinn-Zong

2017-03-01

During myocardial infarction, infiltrated macrophages have pivotal roles in cardiac remodeling and delayed M1 toward M2 macrophage phenotype transition is considered one of the major factors for adverse ventricular remodeling. We investigated whether dapagliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor, attenuates cardiac fibrosis via regulating macrophage phenotype by a reactive oxygen and nitrogen species (RONS)/STAT3-dependent pathway in postinfarcted rats. Normoglycemic male Wistar rats were subjected to coronary ligation and then randomized to either saline, dapagliflozin (a specific SGLT2 inhibitor), phlorizin (a nonspecific SGLT1/2 inhibitor), dapagliflozin + S3I-201 (a STAT3 inhibitor), or phlorizin + S3I-201 for 4 weeks. There were similar infarct sizes among the infarcted groups at the acute and chronic stages of infarction. At day 3 after infarction, post-infarction was associated with increased levels of superoxide and nitrotyrosine, which can be inhibited by administering either dapagliflozin or phlorizin. SGLT2 inhibitors significantly increased STAT3 activity, STAT3 nuclear translocation, myocardial IL-10 levels and the percentage of M2 macrophage infiltration. At day 28 after infarction, SGLT2 inhibitors were associated with attenuated myofibroblast infiltration and cardiac fibrosis. Although phlorizin decreased myofibroblast infiltration, the effect of dapagliflozin on attenuated myofibroblast infiltration was significantly higher than phlorizin. The effects of SGLT2 inhibitors on cardiac fibrosis were nullified by adding S3I-201. Furthermore, the effects of dapagliflozin on STAT3 activity and myocardial IL-10 levels can be reversed by 3-morpholinosydnonimine, a peroxynitrite generator. Taken together, these observations provide a novel mechanism of SGLT2 inhibitors-mediated M2 polarization through a RONS-dependent STAT3-mediated pathway and selective SGLT2 inhibitors are more effective in attenuating myofibroblast infiltration during postinfarction remodeling. Copyright © 2017 Elsevier Inc. All rights reserved.

Design and synthesis of (aza)indolyl maleimide-based covalent inhibitors of glycogen synthase kinase 3β.

PubMed

Yang, Zhimin; Liu, Hui; Pan, Botao; He, Fengli; Pan, Zhengying

2018-05-21

As an important kinase in multiple signal transduction pathways, GSK-3β has been an attractive target for chemical probe discovery and drug development. Compared to numerous reversible inhibitors that have been developed, covalent inhibitors of GSK-3β are noticeably lacking. Here, we report the discovery of a series of covalent GSK-3β inhibitors by optimizing both non-covalent interactions and reactive groups. Among these covalent inhibitors, compound 38b with a mild α-fluoromethyl amide reactive group emerges as a selective and covalent inhibitor against GSK-3β, effectively inhibits the phosphorylation of glycogen synthase and tau protein, and increases β-catenin's levels in living cells. In addition, compound 38b is highly permeable and not a substrate of P-glycoprotein.

Electrostatic Interactions Positively Regulate K-Ras Nanocluster Formation and Function▿

PubMed Central

Plowman, Sarah J.; Ariotti, Nicholas; Goodall, Andrew; Parton, Robert G.; Hancock, John F.

2008-01-01

The organization of Ras proteins into plasma membrane nanoclusters is essential for high-fidelity signal transmission, but whether the nanoscale enviroments of different Ras nanoclusters regulate effector interactions is unknown. We show using high-resolution spatial mapping that Raf-1 is recruited to and retained in K-Ras-GTP nanoclusters. In contrast, Raf-1 recruited to the plasma membrane by H-Ras is not retained in H-Ras-GTP nanoclusters. Similarly, upon epidermal growth factor receptor activation, Raf-1 is preferentially recruited to K-Ras-GTP and not H-Ras-GTP nanoclusters. The formation of K-Ras-GTP nanoclusters is inhibited by phosphorylation of S181 in the C-terminal polybasic domain or enhanced by blocking S181 phosphorylation, with a concomitant reduction or increase in Raf-1 plasma membrane recruitment, respectively. Phosphorylation of S181 does not, however, regulate in vivo interactions with the nanocluster scaffold galectin-3 (Gal3), indicating separate roles for the polybasic domain and Gal3 in driving K-Ras nanocluster formation. Together, these data illustrate that Ras nanocluster composition regulates effector recruitment and highlight the importance of lipid/protein nanoscale environments to the activation of signaling cascades. PMID:18458061

EZH2 and histone deacetylase inhibitors induce apoptosis in triple negative breast cancer cells by differentially increasing H3 Lys27 acetylation in the BIM gene promoter and enhancers.

PubMed

Huang, Julia P; Ling, Kun

2017-11-01

Enhancer of zeste homolog 2 (EZH2), a subunit of polycomb repressive complex 2, is a histone methyl-transferase and is considered to work cooperatively with histone deacetylases (HDACs) in the same protein complex to mediate gene transcription repression by increasing histone H3 Lys 27 trimethylation (H3K27me3), in particular in the nucleosome (s). EZH2 is overexpressed in numerous types of cancer, including triple negative breast cancer (TNBC), a subtype of breast cancer, which there are no effective treatment options for. Thus, inhibition of EZH2 may be harnessed for targeted therapy of this disease. The present study demonstrated that co-treatment with an EZH2 inhibitor and a HDAC inhibitor additively induced apoptosis in two TNBC cell lines, namely MDA-MB-231 and MDA-MB-436. The increased rate of cell death was associated with an elevation of B cell lymphoma-2 like 11 (BIM) expression level, a pro-apoptotic protein at the protein and mRNA expression levels in these two cell lines. The expression of forkhead box O1 (FOXO1), a known upstream transcriptional activator of BIM , was upregulated in both cell lines by the HDAC inhibitor, and the effect was more pronounced in MDA-MB-436 cells with higher phosphorylation levels of protein kinase B, a negative regulator of FOXO1, compared with MDA-MB-231 cells. Conversely, FOXO1 expression was inhibited following treatment with the EZH2 inhibitor, suggesting that EZH2 and HDAC inhibitors induced BIM expression via a FOXO1-independent mechanism. The present study further revealed that the EZH2 inhibitor, but not the HDAC inhibitor, induced high levels of H3K27 acetylation (H3K27ac) in the BIM promoter. By contrast, compared with the effect of the EZH2 inhibitor, HDAC inhibitor treatment resulted in an increase in H3K27ac at two BIM enhancers. Collectively, the results of the present study indicated that EZH2 and HDACs act differentially on H3K27ac levels in the nucleosome at the promoter and enhancer regions of the BIM gene. Through the upregulation of BIM, co-treatment with EZH2 and HDAC inhibitors had a pronounced therapeutic effect on TNBC cells, suggesting that co-targeting EZH2 and HDAC proteins represents a viable therapeutic option for the treatment of TNBC.

PDE 5 inhibitor improves insulin sensitivity by enhancing mitochondrial function in adipocytes.

PubMed

Yu, Hea Min; Chung, Hyo Kyun; Kim, Koon Soon; Lee, Jae Min; Hong, Jun Hwa; Park, Kang Seo

2017-11-04

Adipocytes are involved in many metabolic disorders. It was recently reported that phosphodiesterase type 5 (PDE5) is expressed in human adipose tissue. In addition, PDE5 inhibitors have been shown to improve insulin sensitivity in humans. However, the mechanism underlying the role of PDE5 inhibitors as an insulin sensitizer remains largely unknown. The present study was undertaken to investigate the role of the PDE5 inhibitor udenafil in insulin signaling in adipocytes and whether this is mediated through the regulation of mitochondrial function. To study the mechanism underlying the insulin sensitizing action of PDE5 inhibitors, we evaluated quantitative changes in protein or mRNA levels of mitochondrial oxidative phosphorylation (OxPhos) complex, oxygen consumption rate (OCR), and fatty acid oxidation with varying udenafil concentrations in 3T3-L1 cells. Our cell study suggested that udenafil enhanced the insulin signaling pathway in 3T3-L1 cells. Following udenafil treatment, basal mitochondrial OCR, maximal OxPhos capacity, and OxPhos gene expression significantly increased. Finally, we examined whether udenafil can affect the fatty acid oxidation process. Treatment of 3T3-L1 cells with udenafil (10 and 20 μM) significantly increased fatty acid oxidation rate in a dose-dependent manner. In addition, the expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) significantly increased. We demonstrated that the PDE5 inhibitor udenafil enhances insulin sensitivity by improving mitochondrial function in 3T3-L1 cells. This might be the mechanism underlying the PDE5 inhibitor-enhanced insulin signaling in adipocytes. This also suggests that udenafil may provide benefit in the treatment of type 2 diabetes and other related cardiovascular diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Quantitative characterization of galectin-3-C affinity mass spectrometry measurements: Comprehensive data analysis, obstacles, shortcuts and robustness.

PubMed

Haramija, Marko; Peter-Katalinić, Jasna

2017-10-30

Affinity mass spectrometry (AMS) is an emerging tool in the field of the study of protein•carbohydrate complexes. However, experimental obstacles and data analysis are preventing faster integration of AMS methods into the glycoscience field. Here we show how analysis of direct electrospray ionization mass spectrometry (ESI-MS) AMS data can be simplified for screening purposes, even for complex AMS spectra. A direct ESI-MS assay was tested in this study and binding data for the galectin-3C•lactose complex were analyzed using a comprehensive and simplified data analysis approach. In the comprehensive data analysis approach, noise, all protein charge states, alkali ion adducts and signal overlap were taken into account. In a simplified approach, only the intensities of the fully protonated free protein and the protein•carbohydrate complex for the main protein charge state were taken into account. In our study, for high intensity signals, noise was negligible, sodiated protein and sodiated complex signals cancelled each other out when calculating the K d value, and signal overlap influenced the Kd value only to a minor extent. Influence of these parameters on low intensity signals was much higher. However, low intensity protein charge states should be avoided in quantitative AMS analyses due to poor ion statistics. The results indicate that noise, alkali ion adducts, signal overlap, as well as low intensity protein charge states, can be neglected for preliminary experiments, as well as in screening assays. One comprehensive data analysis performed as a control should be sufficient to validate this hypothesis for other binding systems as well. Copyright © 2017 John Wiley & Sons, Ltd.

Mitochondrial Respiratory Chain Inhibitors Involved in ROS Production Induced by Acute High Concentrations of Iodide and the Effects of SOD as a Protective Factor

PubMed Central

Wang, Lingyan; Duan, Qi; Wang, Tingting; Ahmed, Mohamed; Zhang, Na; Li, Yongmei; Li, Lanying; Yao, Xiaomei

2015-01-01

A major source of reactive oxygen species (ROS) generation is the mitochondria. By using flow cytometry of the mitochondrial fluorescent probe, MitoSOX Red, western blot of mitochondrial ROS scavenger Peroxiredoxin (Prx) 3 and fluorescence immunostaining, ELISA of cleaved caspases 3 and 9, and TUNEL staining, we demonstrated that exposure to 100 μM KI for 2 hours significantly increased mitochondrial superoxide production and Prx 3 protein expression with increased expressions of cleaved caspases 3 and 9. Besides, we indicated that superoxide dismutase (SOD) at 1000 unit/mL attenuated the increase in mitochondrial superoxide production, Prx 3 protein expression, and lactate dehydrogenase (LDH) release and improved the relative cell viability at 100 μM KI exposure. However, SOD inhibitor diethyldithiocarbamic acid (DETC) (2 mM), Rotenone (0.5 μM), a mitochondrial complex I inhibitor, and Antimycin A (10 μM), a complex III inhibitor, caused an increase in mitochondrial superoxide production, Prx 3 protein expression, and LDH release and decreased the relative cell viability. We conclude that the inhibitors of mitochondrial respiratory chain complex I or III may be involved in oxidative stress caused by elevated concentrations of iodide, and SOD demonstrates its protective effect on the Fischer rat thyroid cell line (FRTL) cells. PMID:26294939

Celecoxib promotes c-FLIP degradation through Akt-independent inhibition of GSK3.

PubMed

Chen, Shuzhen; Cao, Wei; Yue, Ping; Hao, Chunhai; Khuri, Fadlo R; Sun, Shi-Yong

2011-10-01

Celecoxib is a COX-2 inhibitor that reduces the risk of colon cancer. However, the basis for its cancer chemopreventive activity is not fully understood. In this study, we defined a mechanism of celecoxib action based on degradation of cellular FLICE-inhibitory protein (c-FLIP), a major regulator of the death receptor pathway of apoptosis. c-FLIP protein levels are regulated by ubiquitination and proteasome-mediated degradation. We found that celecoxib controlled c-FLIP ubiquitination through Akt-independent inhibition of glycogen synthase kinase-3 (GSK3), itself a candidate therapeutic target of interest in colon cancer. Celecoxib increased the levels of phosphorylated GSK3, including the α and β forms, even in cell lines, where phosphorylated Akt levels were not increased. Phosphoinositide 3-kinase inhibitors abrogated Akt phosphorylation as expected but had no effect on celecoxib-induced GSK3 phosphorylation. In contrast, protein kinase C (PKC) inhibitors abolished celecoxib-induced GSK3 phosphorylation, implying that celecoxib influenced GSK3 phosphorylation through a mechanism that relied upon PKC and not Akt. GSK3 blockade either by siRNA or kinase inhibitors was sufficient to attenuate c-FLIP levels. Combining celecoxib with GSK3 inhibition enhanced attenuation of c-FLIP and increased apoptosis. Proteasome inhibitor MG132 reversed the effects of GSK3 inhibition and increased c-FLIP ubiquitination, confirming that c-FLIP attenuation was mediated by proteasomal turnover as expected. Our findings reveal a novel mechanism through which the regulatory effects of c-FLIP on death receptor signaling are controlled by GSK3, which celecoxib acts at an upstream level to control independently of Akt.

Celecoxib promotes c-FLIP degradation through Akt-independent inhibition of GSK3

PubMed Central

Chen, Shuzhen; Cao, Wei; Yue, Ping; Hao, Chunhai; Khuri, Fadlo R.; Sun, Shi-Yong

2011-01-01

Celecoxib is a COX2 inhibitor that reduces the risk of colon cancer. However, the basis for its cancer chemopreventive activity is not fully understood. In this study, we defined a mechanism of celecoxib action based on degradation of c-FLIP, a major regulator of the death receptor pathway of apoptosis. c-FLIP protein levels are regulated by ubiquitination and proteasome-mediated degradation. We found that celecoxib controlled c-FLIP ubiquitination through Akt-independent inhibition of GSK3 kinase, itself a candidate therapeutic target of interest in colon cancer. Celecoxib increased the levels of phosphorylated GSK3 (p-GSK3), including the α and β forms, even in cell lines where p-Akt levels were not increased. PI3K inhibitors abrogated Akt phosphorylation as expected but had no effect on celecoxib-induced GSK3 phosphorylation. In contrast, PKC inhibitors abolished celecoxib-induced GSK3 phosphorylation, implying that celecoxib influenced GSK3 phosphorylation through a mechanism relied upon PKC but not Akt. GSK3 blockade either by siRNA or kinase inhibitors was sufficient to attenuate c-FLIP levels. Combining celecoxib with GSK3 inhibition enhanced attenuation of c-FLIP and increased apoptosis. Proteasome inhibitor MG132 reversed the effects of GSK3 inhibition and increased c-FLIP ubiquitination, confirming that c-FLIP attenuation was mediated by proteasomal turnover as expected. Our findings reveal a novel mechanism through which the regulatory effects of c-FLIP on death receptor signaling are controlled by GSK3, which celecoxib acts at an upstream level to control independently of Akt. PMID:21868755

Corrosion mitigation of N-(2-hydroxy-3-trimethyl ammonium)propyl chitosan chloride as inhibitor on mild steel.

PubMed

Sangeetha, Y; Meenakshi, S; SairamSundaram, C

2015-01-01

The biopolymer N-(2-hydroxy-3-trimethyl ammonium)propyl chitosan chloride (HTACC) was synthesised and its influence as a novel corrosion inhibitor on mild steel in 1M HCl was studied using gravimetric and electrochemical experiments. The compound obtained was characterised using FTIR and NMR studies. The inhibition efficiency increased with the increase in concentration and reached a maximum of 98.9% at 500 ppm concentration. Polarisation studies revealed that HTACC acts both as anodic and cathodic inhibitor. Electrochemical impedance studies confirmed that the inhibition is through adsorption on the metal surface. The extent of inhibition exhibits a negative trend with increase in temperature. Langmuir isotherm provides the best description on the adsorption nature of the inhibitor. SEM analysis indicated the presence of protective film formed by the inhibitor on the metal surface. Copyright © 2014 Elsevier B.V. All rights reserved.

Galectin-3 Induces Clustering of CD147 and Integrin-β1 Transmembrane Glycoprotein Receptors on the RPE Cell Surface

PubMed Central

Priglinger, Claudia S.; Szober, Christoph M.; Priglinger, Siegfried G.; Merl, Juliane; Euler, Kerstin N.; Kernt, Marcus; Gondi, Gabor; Behler, Jennifer; Geerlof, Arie; Kampik, Anselm; Ueffing, Marius; Hauck, Stefanie M.

2013-01-01

Proliferative vitreoretinopathy (PVR) is a blinding disease frequently occurring after retinal detachment surgery. Adhesion, migration and matrix remodeling of dedifferentiated retinal pigment epithelial (RPE) cells characterize the onset of the disease. Treatment options are still restrained and identification of factors responsible for the abnormal behavior of the RPE cells will facilitate the development of novel therapeutics. Galectin-3, a carbohydrate-binding protein, was previously found to inhibit attachment and spreading of retinal pigment epithelial cells, and thus bares the potential to counteract PVR-associated cellular events. However, the identities of the corresponding cell surface glycoprotein receptor proteins on RPE cells are not known. Here we characterize RPE-specific Gal-3 containing glycoprotein complexes using a proteomic approach. Integrin-β1, integrin-α3 and CD147/EMMPRIN, a transmembrane glycoprotein implicated in regulating matrix metalloproteinase induction, were identified as potential Gal-3 interactors on RPE cell surfaces. In reciprocal immunoprecipitation experiments we confirmed that Gal-3 associated with CD147 and integrin-β1, but not with integrin-α3. Additionally, association of Gal-3 with CD147 and integrin-β1 was observed in co-localization analyses, while integrin-α3 only partially co-localized with Gal-3. Blocking of CD147 and integrin-β1 on RPE cell surfaces inhibited binding of Gal-3, whereas blocking of integrin-α3 failed to do so, suggesting that integrin-α3 is rather an indirect interactor. Importantly, Gal-3 binding promoted pronounced clustering and co-localization of CD147 and integrin-β1, with only partial association of integrin-α3. Finally, we show that RPE derived CD147 and integrin-β1, but not integrin-α3, carry predominantly β-1,6-N-actyl-D-glucosamine-branched glycans, which are high-affinity ligands for Gal-3. We conclude from these data that extracellular Gal-3 triggers clustering of CD147 and integrin-β1 via interaction with β1,6-branched N-glycans on RPE cells and hypothesize that Gal-3 acts as a positive regulator for CD147/integrin-β1 clustering and therefore modifies RPE cell behavior contributing to the pathogenesis of PVR. Further investigations at this pathway may aid in the development of specific therapies for PVR. PMID:23922889

Design and Synthesis of Novel Arylketo-containing P1-P3 Linked Macro-cyclic BACE-1 Inhibitors

PubMed Central

Sandgren, Veronica; Belda, Oscar; Kvarnström, Ingemar; Lindberg, Jimmy; Samuelsson, Bertil; Dahlgren, Anders

2015-01-01

A series of arylketo-containing P1-P3 linked macrocyclic BACE-1 inhibitors were designed, synthesized, and compared with compounds with a previously known and extensively studied corresponding P2 isophthalamide moiety with the aim to improve on permeability whilst retaining the enzyme- and cell-based activities. Several inhibitors displayed substantial increases in Caco-2 cell-based permeability compared to earlier synthesized inhibitors and notably also with retained activities, showing that this approach might yield BACE-1 inhibitors with improved properties. PMID:25937848

Concurrent Inhibition of Pim and FLT3 Kinases Enhances Apoptosis of FLT3-ITD Acute Myeloid Leukemia Cells through Increased Mcl-1 Proteasomal Degradation.

PubMed

Kapoor, Shivani; Natarajan, Karthika; Baldwin, Patrick R; Doshi, Kshama A; Lapidus, Rena G; Mathias, Trevor J; Scarpa, Mario; Trotta, Rossana; Davila, Eduardo; Kraus, Manfred; Huszar, Dennis; Tron, Adriana E; Perrotti, Danilo; Baer, Maria R

2018-01-01

Purpose: fms -like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) is present in 30% of acute myeloid leukemia (AML), and these patients have short disease-free survival. FLT3 inhibitors have limited and transient clinical activity, and concurrent treatment with inhibitors of parallel or downstream signaling may improve responses. The oncogenic serine/threonine kinase Pim-1 is upregulated downstream of FLT3-ITD and also promotes its signaling in a positive feedback loop, suggesting benefit of combined Pim and FLT3 inhibition. Experimental Design: Combinations of clinically active Pim and FLT3 inhibitors were studied in vitro and in vivo Results: Concurrent treatment with the pan-Pim inhibitor AZD1208 and FLT3 inhibitors at clinically applicable concentrations abrogated in vitro growth of FLT3-ITD, but not wild-type FLT3 (FLT3-WT), cell lines. AZD1208 cotreatment increased FLT3 inhibitor-induced apoptosis of FLT3-ITD, but not FLT3-WT, cells measured by sub-G 1 fraction, annexin V labeling, mitochondrial membrane potential, and PARP and caspase-3 cleavage. Concurrent treatment with AZD1208 and the FLT3 inhibitor quizartinib decreased growth of MV4-11 cells, with FLT3-ITD, in mouse xenografts, and prolonged survival, enhanced apoptosis of FLT3-ITD primary AML blasts, but not FLT3-WT blasts or remission marrow cells, and decreased FLT3-ITD AML blast colony formation. Mechanistically, AZD1208 and quizartinib cotreatment decreased expression of the antiapoptotic protein Mcl-1. Decrease in Mcl-1 protein expression was abrogated by treatment with the proteasome inhibitor MG132, and was preceded by downregulation of the Mcl-1 deubiquitinase USP9X, a novel mechanism of Mcl-1 regulation in AML. Conclusions: The data support clinical testing of Pim and FLT3 inhibitor combination therapy for FLT3-ITD AML. Clin Cancer Res; 24(1); 234-47. ©2017 AACR . ©2017 American Association for Cancer Research.

Pharmacokinetic Interactions between Nelfinavir and 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase Inhibitors Atorvastatin and Simvastatin

PubMed Central

Hsyu, Poe-Hirr; Schultz-Smith, Melissa D.; Lillibridge, James H.; Lewis, Ronald H.; Kerr, Bradley M.

2001-01-01

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are effective agents in lowering cholesterol and triglycerides and are being used by human immunodeficiency virus-positive patients to treat the lipid elevation that may be associated with antiretroviral therapy. Many HMG-CoA reductase inhibitors and protease inhibitors are metabolized by the same cytochrome P450 enzyme 3A4 (CYP3A4). In addition, many protease inhibitors are potent inhibitors of CYP3A4. Therefore, coadministration of these two classes of drugs may cause significant drug interactions. This open-label, multiple-dose study was performed to determine the interactions between nelfinavir, a protease inhibitor, and two HMG-CoA reductase inhibitors, atorvastatin and simvastatin, in healthy volunteers. Thirty-two healthy subjects received either atorvastatin calcium (10 mg once a day) or simvastatin (20 mg once a day) for the first 14 days of the study. Nelfinavir (1,250 mg twice a day) was added on days 15 to 28. Pharmacokinetic assessment was performed on days 14 and 28. The study drugs were well tolerated. Nelfinavir increased the steady-state area under the plasma concentration-time curve during one dosing period (AUCτ) of atorvastatin 74% and the maximum concentration (Cmax) of atorvastatin 122% and increased the AUCτ of simvastatin 505% and the Cmax of simvastatin 517%. Neither atorvastatin nor simvastatin appeared to alter the pharmacokinetics of nelfinavir. It is recommended that coadministration of simvastatin with nelfinavir should be avoided, whereas atorvastatin should be used with nelfinavir with caution. PMID:11709322

Increased uptake of [123I]-meta-iodobenzylguanidine and [18F]-dopamine in mouse pheochromocytoma cells and tumors after treatment with the histone deacetylase inhibitors romidepsin and trichostatin A

PubMed Central

Martiniova, Lucia; Perera, Shiromi M.; Brouwers, Frederieke M.; Alesci, Salvatore; Abu-Asab, Mones; Marvelle, Amanda F.; Kiesewetter, Dale O.; Thomasson, David; Morris, John C.; Kvetnansky, Richard; Tischler, Arthur S.; Reynolds, James C; Fojo, A. Tito; Pacak, Karel

2014-01-01

Purpose [131I]-meta-iodobenzylguanidine ([131I]-MIBG) is the most commonly employed treatment for metastatic pheochromocytoma and paraganglioma; however, its success is limited. Its efficacy depends on the [131I]-MIBG concentration reached within the tumor through its uptake via the norepinephrine transporter and retention in neurosecretory granules. Purpose is to enhance [123I]-MIBG uptake in cells and liver pheochromocytoma tumors. Experimental Design We report the in vitro effects of two histone deacetylase (HDAC) inhibitors, romidepsin and trichostatin A, on increased uptake of [3H]-norepinephrine and [123I]-MIBG in mouse pheochromocytoma (MPC) cells, and the effect of romidepsin on [18F]-fluorodopamine and [123I]-MIBG uptake in a mouse model of metastatic pheochromocytoma. The effects of both inhibitors on norepinephrine transporter activity were assessed in MPC cells by [123I]-MIBG uptake studies with and without the transporter blocking agent desipramine and the vesicular blocking agent reserpine. Results Both HDAC inhibitors increased [3H]-norepinephrine, [123I]-MIBG, and [18F]-fluorodopamine uptake through the norepinephrine transporter in MPC cells. In vivo, inhibitor treatment resulted in increased uptake of [18F]-fluorodopamine and in pheochromocytoma liver metastases as measured by maximal standardized uptake values on PET imaging (p < 0.001). Analysis of biodistribution after inhibitor treatment confirmed the PET results in that uptake of [123I]-MIBG was significantly increased in liver metastases (p < 0.05). Therefore, HDAC inhibitor treatment increased radioisotope uptake in MPC cells in vitro and in liver metastases in vivo, through increased norepinephrine transporter activity. Conclusion These results suggest that HDAC inhibitors could enhance the therapeutic efficacy of [131I]-MIBG treatment in patients with malignant pheochromocytoma. PMID:21098082

Galectin-8 induces partial epithelial–mesenchymal transition with invasive tumorigenic capabilities involving a FAK/EGFR/proteasome pathway in Madin–Darby canine kidney cells

PubMed Central

Oyanadel, Claudia; Holmes, Christopher; Pardo, Evelyn; Retamal, Claudio; Shaughnessy, Ronan; Smith, Patricio; Cortés, Priscilla; Bravo-Zehnder, Marcela; Metz, Claudia; Feuerhake, Teo; Romero, Diego; Roa, Juan Carlos; Montecinos, Viviana; Soza, Andrea; González, Alfonso

2018-01-01

Epithelial cells can acquire invasive and tumorigenic capabilities through epithelial–mesenchymal-transition (EMT). The glycan-binding protein galectin-8 (Gal-8) activates selective β1-integrins involved in EMT and is overexpressed by certain carcinomas. Here we show that Gal-8 overexpression or exogenous addition promotes proliferation, migration, and invasion in nontumoral Madin–Darby canine kidney (MDCK) cells, involving focal-adhesion kinase (FAK)-mediated transactivation of the epidermal growth factor receptor (EGFR), likely triggered by α5β1integrin binding. Under subconfluent conditions, Gal-8–overexpressing MDCK cells (MDCK-Gal-8H) display hallmarks of EMT, including decreased E-cadherin and up-regulated expression of vimentin, fibronectin, and Snail, as well as increased β-catenin activity. Changes related to migration/invasion included higher expression of α5β1 integrin, extracellular matrix-degrading MMP13 and urokinase plasminogen activator/urokinase plasminogen activator receptor (uPA/uPAR) protease systems. Gal-8–stimulated FAK/EGFR pathway leads to proteasome overactivity characteristic of cancer cells. Yet MDCK-Gal-8H cells still develop apical/basolateral polarity reverting EMT markers and proteasome activity under confluence. This is due to the opposite segregation of Gal-8 secretion (apical) and β1-integrins distribution (basolateral). Strikingly, MDCK-Gal-8H cells acquired tumorigenic potential, as reflected in anchorage-independent growth in soft agar and tumor generation in immunodeficient NSG mice. Therefore, Gal-8 can promote oncogenic-like transformation of epithelial cells through partial and reversible EMT, accompanied by higher proliferation, migration/invasion, and tumorigenic properties. PMID:29298841

Getting too sweet: galectin-1 dysregulation in gestational diabetes mellitus.

PubMed

Blois, Sandra M; Gueuvoghlanian-Silva, Barbara Y; Tirado-González, Irene; Torloni, Maria R; Freitag, Nancy; Mattar, Rosiane; Conrad, Melanie L; Unverdorben, Laura; Barrientos, Gabriela; Knabl, Julia; Toldi, Gergely; Molvarec, Attila; Rose, Matthias; Markert, Udo R; Jeschke, Udo; Daher, Silvia

2014-07-01

Galectin-1 (gal-1) is a prototype carbohydrate-binding protein, whose dysregulation is associated with adverse pregnancy outcomes such as spontaneous abortion and pre-eclampsia. Furthermore, it is known that faulty gal-1 protein production or gene regulation can be caused by single-nucleotide polymorphisms in the LGALS1 gene. Gestational diabetes mellitus (GDM) is also an adverse pregnancy outcome and the most common metabolic disorder during gestation. However, gal-1 expression patterns during GDM remain largely unknown. Our aims were to define local and peripheral gal-1 expression patterns during pregnancy, and to investigate LGALS1 gene polymorphisms in GDM patients. Circulating gal-1 levels were determined by ELISA in GDM patients and normal pregnant controls, and LGALS1 gene polymorphisms were assessed for association with GDM. Placental tissues were collected from control and GDM term pregnancies to evaluate local gal-1 expression by immunofluorescence. Our results show that GDM is associated with a failure to increase circulating gal-1 levels during the second and third trimester, as well as overexpression of gal-1 in placental tissue. Additionally, the LGALS1 polymorphism rs4820294 was associated with the development of GDM. In pregnancies complicated by GDM, we observed gal-1 dysregulation both locally in the placenta and peripherally in the circulation. Furthermore, the association between the LGALS1 polymorphism and GDM may indicate a genetic contribution to this adverse pregnancy outcome. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Screening of binding proteins that interact with Chinese sacbrood virus VP3 capsid protein in Apis cerana larvae cDNA library by the yeast two-hybrid method.

PubMed

Fei, Dongliang; Wei, Dong; Yu, Xiaolei; Yue, Jinjin; Li, Ming; Sun, Li; Jiang, Lili; Li, Yijing; Diao, Qingyun; Ma, Mingxiao

2018-03-15

Chinese sacbrood virus (CSBV) causes larval death and apiary collapse of Apis cerana. VP3 is a capsid protein of CSBV but its function is poorly understood. To determine the function of VP3 and screen for novel binding proteins that interact with VP3, we conducted yeast two-hybrid screening, glutathione S-transferase pull-down, and co-immunoprecipitation assays. Galectin (GAL) is a protein involved in immune regulation and host-pathogen interactions. The yeast two-hybrid screen implicated GAL as a major VP3-binding candidate. The assays showed that the VP3 interacted with GAL. Identification of these cellular targets and clarifying their contributions to the host-pathogen interaction may be useful for the development of novel therapeutic and prevention strategies against CSBV infection. Copyright © 2018 Elsevier B.V. All rights reserved.

The synergistic interaction of MEK and PI3K inhibitors is modulated by mTOR inhibition.

PubMed

Haagensen, E J; Kyle, S; Beale, G S; Maxwell, R J; Newell, D R

2012-04-10

Combined targeting of MAPK and PI3K signalling pathways may be necessary for optimal therapeutic activity in cancer. This study evaluated the MEK inhibitors AZD6244 and PD0325901, alone and in combination with the dual mTOR/PI3K inhibitor NVP-BEZ235 or the PI3K inhibitor GDC-0941, in three colorectal cancer cell lines. Growth inhibition, survival and signal transduction were measured using the Sulforhodamine B assay, clonogenicity and western blotting, respectively, in HCT116, HT29 and DLD1 cell lines. All MEK/PI3K inhibitor combinations exhibited marked synergistic growth inhibition; however, GDC-0941 displayed greater synergy in combination with either MEK inhibitor. NVP-BEZ235 exhibited stronger inhibition of 4EBP1 phosphorylation, and similar inhibition of S6 and AKT phosphorylation, compared with GDC-0941. Both PD0325901 and AZD6244 inhibited ERK phosphorylation, and with MEK/PI3K inhibitor combinations inhibition of S6 phosphorylation was increased. The reduced synergy exhibited by NVP-BEZ235 in combination with MEK inhibitors, compared with GDC-0941, may be due to inhibition of mTOR, and the addition of the mTORC1/2 inhibitor KU0063794 compromised the synergy of GDC-0941:PD0325901 combinations. These studies confirm that dual targeting of PI3K and MEK can induce synergistic growth inhibition; however, the combination of specific PI3K inhibitors, rather than dual mTOR/PI3K inhibitors, with MEK inhibitors results in greater synergy.

The synergistic interaction of MEK and PI3K inhibitors is modulated by mTOR inhibition

PubMed Central

Haagensen, E J; Kyle, S; Beale, G S; Maxwell, R J; Newell, D R

2012-01-01

Background: Combined targeting of MAPK and PI3K signalling pathways may be necessary for optimal therapeutic activity in cancer. This study evaluated the MEK inhibitors AZD6244 and PD0325901, alone and in combination with the dual mTOR/PI3K inhibitor NVP-BEZ235 or the PI3K inhibitor GDC-0941, in three colorectal cancer cell lines. Methods: Growth inhibition, survival and signal transduction were measured using the Sulforhodamine B assay, clonogenicity and western blotting, respectively, in HCT116, HT29 and DLD1 cell lines. Results: All MEK/PI3K inhibitor combinations exhibited marked synergistic growth inhibition; however, GDC-0941 displayed greater synergy in combination with either MEK inhibitor. NVP-BEZ235 exhibited stronger inhibition of 4EBP1 phosphorylation, and similar inhibition of S6 and AKT phosphorylation, compared with GDC-0941. Both PD0325901 and AZD6244 inhibited ERK phosphorylation, and with MEK/PI3K inhibitor combinations inhibition of S6 phosphorylation was increased. The reduced synergy exhibited by NVP-BEZ235 in combination with MEK inhibitors, compared with GDC-0941, may be due to inhibition of mTOR, and the addition of the mTORC1/2 inhibitor KU0063794 compromised the synergy of GDC-0941:PD0325901 combinations. Conclusion: These studies confirm that dual targeting of PI3K and MEK can induce synergistic growth inhibition; however, the combination of specific PI3K inhibitors, rather than dual mTOR/PI3K inhibitors, with MEK inhibitors results in greater synergy. PMID:22415236

Tryptophan Metabolism in Rat Liver After Administration of Tryptophan, Kynurenine Metabolites, and Kynureninase Inhibitors.

PubMed

Badawy, Abdulla A-B; Bano, Samina

2016-01-01

Rat liver tryptophan (Trp), kynurenine pathway metabolites, and enzymes deduced from product/substrate ratios were assessed following acute and/or chronic administration of kynurenic acid (KA), 3-hydroxykynurenine (3-HK), 3-hydroxyanthranilic acid (3-HAA), Trp, and the kynureni-nase inhibitors benserazide (BSZ) and carbidopa (CBD). KA activated Trp 2,3-dioxygenase (TDO), possibly by increasing liver 3-HAA, but inhibited kynurenine aminotransferase (KAT) and kynureninase activities with 3-HK as substrate. 3-HK inhibited kynureninase activity from 3-HK. 3-HAA stimulated TDO, but inhibited kynureninase activity from K and 3-HK. Trp (50 mg/kg) increased kynurenine metabolite concentrations and KAT from K, and exerted a temporary stimulation of TDO. The kynureninase inhibitors BSZ and CBD also inhibited KAT, but stimulated TDO. BSZ abolished or strongly inhibited the Trp-induced increases in liver Trp and kynurenine metabolites. The potential effects of these changes in conditions of immune activation, schizophrenia, and other disease states are discussed.

Nephrotoxicity of Epigenetic Inhibitors Used for the Treatment of Cancer

PubMed Central

Scholpa, N.E.; Kolli, R.T.; Moore, M.; Arnold, R.D.; Glenn, T.C.; Cummings, B.S.

2016-01-01

This study determined the anti-neoplastic activity and nephrotoxicity of epigenetic inhibitors in vitro. The therapeutic efficacy of epigenetic inhibitors was determined in human prostate cancer cells (PC-3 and LNCaP) using the DNA methyltransferase inhibitor 5-azacytidine (5-Aza) and the histone deacetylase inhibitor trichostatin A (TSA). Cells were also treated with carbamazepine (CBZ), an anti-convulsant with histone deacetylase inhibitor-like properties. 5-Aza, TSA or CBZ alone did not decrease MTT staining in PC-3 or LNCaP cells after 48 hr. In contrast, docetaxel, a frontline chemotherapeutic induced concentration-dependent decreases in MTT staining. Pretreatment with 5-Aza or TSA increased docetaxel-induced cytotoxicity in LNCaP cells, but not PC-3 cells. TSA pretreatment also increased cisplatin-induced toxicity in LNCaP cells. Carfilzomib (CFZ), a protease inhibitor approved for the treatment of multiple myeloma had minimal effect on LNCaP cell viability, but reduced MTT staining 50% in PC-3 cells compared to control, and pretreatment with 5-Aza further enhanced toxicity. Treatment of normal rat kidney (NRK) and human embryonic kidney 293 (HEK293) cells with the same concentrations of epigenetic inhibitors used in prostate cancer cells significantly decreased MTT staining in all cell lines after 48 hr. Interestingly, we found that the toxicity of epigenetic inhibitors to kidney cells was dependent on both the compound and the stage of cell growth. The effect of 5-Aza and TSA on DNA methyltransferase and histone deacetylase activity, respectively, was confirmed by assessing the methylation and acetylation of the CDK inhibitor p21. Collectively, these data show that combinatorial treatment with epigenetic inhibitors alters the efficacy of chemotherapeutics in cancer cells in a compound- and cell-specific manner; however, this treatment also has the potential to induce nephrotoxic cell injury. PMID:27543423

Improved Therapeutic Effect against Leukemia by a Combination of the Histone Methyltransferase Inhibitor Chaetocin and the Histone Deacetylase Inhibitor Trichostatin A

PubMed Central

Tran, Huong Thi Thanh; Kim, Hee Nam; Lee, Il-Kwon; Nguyen-Pham, Thanh-Nhan; Ahn, Jae-Sook; Kim, Yeo-Kyeoung; Lee, Je-Jung; Park, Kyeong-Soo; Kook, Hoon

2013-01-01

SUV39H1 is a histone 3 lysine 9 (H3K9)-specific methyltransferase that is important for heterochromatin formation and the regulation of gene expression. Chaetocin specifically inhibits SUV39H1, resulted in H3K9 methylation reduction as well as reactivation of silenced genes in cancer cells. Histone deacetylase (HDAC) inhibitors inhibit deacetylases and accumulate high levels of acetylation lead to cell cycle arrest and apoptosis. In this study, we demonstrated that treatment with chaetocin enhanced apoptosis in human leukemia HL60, KG1, Kasumi, K562, and THP1 cells. In addition, chaetocin induced the expression of cyclin-dependent kinase inhibitor 2B (p15), E-cadherin (CDH1) and frizzled family receptor 9 (FZD9) through depletion of SUV39H1 and reduced H3K9 methylation in their promoters. Co-treatment with chaetocin and HDAC inhibitor trichostatin A (TSA) dramatically increased apoptosis and produced greater activation of genes. Furthermore, this combined treatment significantly increased loss of SUV39H1 and reduced histone H3K9 trimethylation responses accompanied by increased acetylation. Importantly, co-treatment with chaetocin and TSA produced potent antileukemic effects in leukemia cells derived from patients. These in vitro findings suggest that combination therapy with SUV39H1 and HDAC inhibitors may be of potential value in the treatment of leukemia. PMID:23400519

Amphiregulin and PTEN evoke a multimodal mechanism of acquired resistance to PI3K inhibition

PubMed Central

Edgar, Kyle A.; Crocker, Lisa; Cheng, Eric; Wagle, Marie-Claire; Wongchenko, Matthew; Yan, Yibing; Wilson, Timothy R.; Dompe, Nicholas; Neve, Richard M.; Belvin, Marcia; Sampath, Deepak; Friedman, Lori S.; Wallin, Jeffrey J.

2014-01-01

Phosphoinositide-3 kinase (PI3K) signaling pathway alterations occur broadly in cancer and PI3K is a promising therapeutic target. Here, we investigated acquired resistance to GDC-0941, a PI3K inhibitor in clinical trials. Colorectal cancer (CRC) cells made to be resistant to GDC-0941 were discovered to secrete amphiregulin, which resulted in increased EGFR/MAPK signaling. Moreover, prolonged PI3K pathway inhibition in cultured cells over a period of months led to a secondary loss of PTEN in 40% of the CRC lines with acquired resistance to PI3K inhibition. In the absence of PI3K inhibitor, these PTEN-null PI3K inhibitor-resistant clones had elevated PI3K pathway signaling and decreased sensitivity to MAPK pathway inhibitors. Importantly, PTEN loss was not able to induce resistance to PI3K inhibitors in the absence of amphiregulin, indicating a multimodal mechanism of acquired resistance. The combination of PI3K and MAPK pathway inhibitors overcame acquired resistance in vitro and in vivo. PMID:25053989

Amphiregulin and PTEN evoke a multimodal mechanism of acquired resistance to PI3K inhibition.

PubMed

Edgar, Kyle A; Crocker, Lisa; Cheng, Eric; Wagle, Marie-Claire; Wongchenko, Matthew; Yan, Yibing; Wilson, Timothy R; Dompe, Nicholas; Neve, Richard M; Belvin, Marcia; Sampath, Deepak; Friedman, Lori S; Wallin, Jeffrey J

2014-03-01

Phosphoinositide-3 kinase (PI3K) signaling pathway alterations occur broadly in cancer and PI3K is a promising therapeutic target. Here, we investigated acquired resistance to GDC-0941, a PI3K inhibitor in clinical trials. Colorectal cancer (CRC) cells made to be resistant to GDC-0941 were discovered to secrete amphiregulin, which resulted in increased EGFR/MAPK signaling. Moreover, prolonged PI3K pathway inhibition in cultured cells over a period of months led to a secondary loss of PTEN in 40% of the CRC lines with acquired resistance to PI3K inhibition. In the absence of PI3K inhibitor, these PTEN-null PI3K inhibitor-resistant clones had elevated PI3K pathway signaling and decreased sensitivity to MAPK pathway inhibitors. Importantly, PTEN loss was not able to induce resistance to PI3K inhibitors in the absence of amphiregulin, indicating a multimodal mechanism of acquired resistance. The combination of PI3K and MAPK pathway inhibitors overcame acquired resistance in vitro and in vivo.

Heterogeneous effects of tissue inhibitors of matrix metalloproteinases on cardiac fibroblasts.

PubMed

Lovelock, Joshua D; Baker, Andrew H; Gao, Feng; Dong, Jing-Fei; Bergeron, Angela L; McPheat, Willie; Sivasubramanian, Natarajan; Mann, Douglas L

2005-02-01

The balance between matrix metalloproteinases (MMPs) and their natural inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), plays a critical role in cardiac remodeling. Although a number of studies have characterized the pathophysiological role of MMPs in the heart, very little is known with respect to the role of TIMPs in the heart. To delineate the role of TIMPs in the heart we examined the effects of adenovirus-mediated overexpression of TIMP-1, -2, -3, and -4 in cardiac fibroblasts. Infection of cardiac fibroblasts with adenoviral constructs containing human recombinant TIMP (AdTIMP-1, -2, -3, and -4) provoked a significant (P < 0.0001) 1.3-fold in increase in bromodeoxyuridine (BrdU) incorporation. Similarly, treatment of cardiac fibroblasts with AdTIMP-1-, -2-, -3-, and -4-conditioned medium led to a 1.2-fold increase in BrdU incorporation (P < 0.0001) that was abolished by pretreatment with anti-TIMP-1, -2, -3, and -4 antibodies. The effects of TIMPs were not mimicked by treating the cells with RS-130830, a broad-based MMP inhibitor, suggesting that the effects of TIMPs were independent of their ability to inhibit MMPs. Infection with AdTIMP-1, -2, -3, and -4 led to a significant increase in alpha-smooth muscle actin staining, consistent with TIMP-induced phenotypic differentiation into myofibroblasts. Finally, infection with AdTIMP-2 resulted in a significant increase in collagen synthesis, whereas infection with AdTIMP-3 resulted in a significant increase in fibroblast apoptosis. TIMPs exert overlapping as well as diverse effects on isolated cardiac fibroblasts. The observation that TIMPs stimulate fibroblast proliferation as well as phenotypic differentiation into myofibroblasts suggests that TIMPs may play an important role in tissue repair in the heart that extends beyond their traditional role as MMP inhibitors.

Effects of intravitreal insulin and insulin signaling cascade inhibitors on emmetropization in the chick

PubMed Central

Penha, Alexandra Marcha; Burkhardt, Eva; Schaeffel, Frank

2012-01-01

Purpose Intravitreal insulin has been shown to be a powerful stimulator of myopia in chickens, in particular if the retinal image is degraded or defocused. In most tissues, the insulin receptor activates two main signaling pathways: a) the mitogen-activated protein kinase (MAPK) cascade (e.g., mitogen-activated protein kinasem kinase [MEK] and extracellular regulated kinase [ERK]) and b) the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway. In the current study, insulin was injected, and these pathways were separately inhibited to determine which is activated when the retinal image is defocused by spectacle lenses. Methods Chicks were treated with either +7 D, −7 D, or no lenses. They were intravitreally injected with insulin, the MEK inhibitor U0126, the PI3K inhibitor Ly294002, or a combination of insulin and one of the inhibitors. Refractions and ocular dimension were measured at the beginning and after four days of treatment. The retinal proteins of the chicks were measured with western blots after 2 h and four days of treatment. Incubation occurred with anti-Akt1, anti-Erk1/2, anti-phospho-AktThr308, and anti-phospho-Erk1/2(Thr202/Tyr204) antibodies, and the ratio between the relative intensity of the phospho-form and the total-form was calculated. Results Chicks wearing positive lenses and injected with saline and with PI3K inhibitor compensated for the imposed defocus and became hyperopic. Insulin injections and insulin plus PI3K inhibitor injections prevented lens-induced hyperopia, whereas the MEK inhibitor alone and insulin plus MEK inhibitor had no effect. Obviously, the MEK inhibitor suppressed the effect of insulin on eye growth in the plus lens–treated animals. Chicks treated with negative lenses and injected with insulin, or with insulin plus MEK inhibitor, overcompensated for the imposed defocus. This effect of insulin was not detected in eyes injected with PI3K inhibitor plus insulin, suggesting that the PI3K inhibitor suppressed the effects of insulin in minus lens–treated animals. Insulin increased the ratio of phospho-Akt/total-Akt in animals with normal visual exposure but even more so in chicks wearing plus or minus lenses. The increase was blocked by simultaneous PI3K inhibitor injections in control eyes but not in lens-treated eyes. Insulin also increased the ratio of phospho-ERK/total-ERK in animals with normal visual exposure and in animals wearing positive lenses, compared to U0126- and Ly294002-injected eyes. In contrast, no significant activation of the MEK/ERK pathway was observed in the negative lens–treated animals. Conclusions Intravitreal insulin promoted axial eye growth and stimulated both signaling pathways. The PI3K/Akt pathway was activated in control and plus and minus lens–treated eyes, but the MEK/ERK pathway was activated only with positive lenses or no lenses. With negative lenses, insulin did not stimulate the MEK/ERK signaling cascade. Independent of the pathway stimulated after insulin binding, the effect on insulin was always the same: an increase in eye growth. PMID:23112573

Effects of intravitreal insulin and insulin signaling cascade inhibitors on emmetropization in the chick.

PubMed

Penha, Alexandra Marcha; Burkhardt, Eva; Schaeffel, Frank; Feldkaemper, Marita P

2012-01-01

Intravitreal insulin has been shown to be a powerful stimulator of myopia in chickens, in particular if the retinal image is degraded or defocused. In most tissues, the insulin receptor activates two main signaling pathways: a) the mitogen-activated protein kinase (MAPK) cascade (e.g., mitogen-activated protein kinasem kinase [MEK] and extracellular regulated kinase [ERK]) and b) the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway. In the current study, insulin was injected, and these pathways were separately inhibited to determine which is activated when the retinal image is defocused by spectacle lenses. Chicks were treated with either +7 D, -7 D, or no lenses. They were intravitreally injected with insulin, the MEK inhibitor U0126, the PI3K inhibitor Ly294002, or a combination of insulin and one of the inhibitors. Refractions and ocular dimension were measured at the beginning and after four days of treatment. The retinal proteins of the chicks were measured with western blots after 2 h and four days of treatment. Incubation occurred with anti-Akt1, anti-Erk1/2, anti-phospho-Akt(Thr308), and anti-phospho-Erk1/2((Thr202/Tyr204)) antibodies, and the ratio between the relative intensity of the phospho-form and the total-form was calculated. Chicks wearing positive lenses and injected with saline and with PI3K inhibitor compensated for the imposed defocus and became hyperopic. Insulin injections and insulin plus PI3K inhibitor injections prevented lens-induced hyperopia, whereas the MEK inhibitor alone and insulin plus MEK inhibitor had no effect. Obviously, the MEK inhibitor suppressed the effect of insulin on eye growth in the plus lens-treated animals. Chicks treated with negative lenses and injected with insulin, or with insulin plus MEK inhibitor, overcompensated for the imposed defocus. This effect of insulin was not detected in eyes injected with PI3K inhibitor plus insulin, suggesting that the PI3K inhibitor suppressed the effects of insulin in minus lens-treated animals. Insulin increased the ratio of phospho-Akt/total-Akt in animals with normal visual exposure but even more so in chicks wearing plus or minus lenses. The increase was blocked by simultaneous PI3K inhibitor injections in control eyes but not in lens-treated eyes. Insulin also increased the ratio of phospho-ERK/total-ERK in animals with normal visual exposure and in animals wearing positive lenses, compared to U0126- and Ly294002-injected eyes. In contrast, no significant activation of the MEK/ERK pathway was observed in the negative lens-treated animals. Intravitreal insulin promoted axial eye growth and stimulated both signaling pathways. The PI3K/Akt pathway was activated in control and plus and minus lens-treated eyes, but the MEK/ERK pathway was activated only with positive lenses or no lenses. With negative lenses, insulin did not stimulate the MEK/ERK signaling cascade. Independent of the pathway stimulated after insulin binding, the effect on insulin was always the same: an increase in eye growth.

Dual inhibition of Bcl-2 and Bcl-xL strikingly enhances PI3K inhibition-induced apoptosis in human myeloid leukemia cells through a GSK3- and Bim-dependent mechanism.

PubMed

Rahmani, Mohamed; Aust, Mandy Mayo; Attkisson, Elisa; Williams, David C; Ferreira-Gonzalez, Andrea; Grant, Steven

2013-02-15

Effects of concomitant inhibition of the PI3K/AKT/mTOR pathway and Bcl-2/Bcl-xL (BCL2L1) were examined in human myeloid leukemia cells. Tetracycline-inducible Bcl-2 and Bcl-xL dual knockdown sharply increased PI3K/AKT/mTOR inhibitor lethality. Conversely, inducible knockdown or dominant-negative AKT increased, whereas constitutively active AKT reduced lethality of the Bcl-2/Bcl-xL inhibitor ABT-737. Furthermore, PI3K/mTOR inhibitors (e.g., BEZ235 and PI-103) synergistically increased ABT-737-mediated cell death in multiple leukemia cell lines and reduced colony formation in leukemic, but not normal, CD34+ cells. Notably, increased lethality was observed in four of six primary acute myelogenous leukemia (AML) specimens. Responding, but not nonresponding, samples exhibited basal AKT phosphorylation. PI3K/mTOR inhibitors markedly downregulated Mcl-1 but increased Bim binding to Bcl-2/Bcl-xL; the latter effect was abrogated by ABT-737. Combined treatment also markedly diminished Bax/Bak binding to Mcl-1, Bcl-2, or Bcl-xL. Bax, Bak, or Bim (BCL2L11) knockdown or Mcl-1 overexpression significantly diminished regimen-induced apoptosis. Interestingly, pharmacologic inhibition or short hairpin RNA knockdown of GSK3α/β significantly attenuated Mcl-1 downregulation and decreased apoptosis. In a systemic AML xenograft model, dual tetracycline-inducible knockdown of Bcl-2/Bcl-xL sharply increased BEZ235 antileukemic effects. In a subcutaneous xenograft model, BEZ235 and ABT-737 coadministration significantly diminished tumor growth, downregulated Mcl-1, activated caspases, and prolonged survival. Together, these findings suggest that antileukemic synergism between PI3K/AKT/mTOR inhibitors and BH3 mimetics involves multiple mechanisms, including Mcl-1 downregulation, release of Bim from Bcl-2/Bcl-xL as well as Bak and Bax from Mcl-1/Bcl-2/Bcl-xL, and GSK3α/β, culminating in Bax/Bak activation and apoptosis. They also argue that combining PI3K/AKT/mTOR inhibitors with BH3 mimetics warrants attention in AML, particularly in the setting of basal AKT activation and/or addiction.

Diversity in recognition of glycans by F-type lectins and galectins: molecular, structural, and biophysical aspects

PubMed Central

Vasta, Gerardo R.; Ahmed, Hafiz; Bianchet, Mario A.; Fernández-Robledo, José A.; Amzel, L. Mario

2013-01-01

Although lectins are “hard-wired” in the germline, the presence of tandemly arrayed carbohydrate recognition domains (CRDs), of chimeric structures displaying distinct CRDs, of polymorphic genes resulting in multiple isoforms, and in some cases, of a considerable recognition plasticity of their carbohydrate binding sites, significantly expand the lectin ligand-recognition spectrum and lectin functional diversification. Analysis of structural/functional aspects of galectins and F-lectins—the most recently identified lectin family characterized by a unique CRD sequence motif (a distinctive structural fold) and nominal specificity for l-Fuc—has led to a greater understanding of self/nonself recognition by proteins with tandemly arrayed CRDs. For lectins with a single CRD, however, recognition of self and nonself glycans can only be rationalized in terms of protein oligomerization and ligand clustering and presentation. Spatial and temporal changes in lectin expression, secretion, and local concentrations in extracellular microenvironments, as well as structural diversity and spatial display of their carbohydrate ligands on the host or microbial cell surface, are suggestive of a dynamic interplay of their recognition and effector functions in development and immunity. PMID:22973821

Fatty-binding protein and galectin of Baylisascaris schroederi: Prokaryotic expression and preliminary evaluation of serodiagnostic potential

PubMed Central

Sun, Ying; Li, Yu; Wu, Yiran; Xiong, Lang; Li, Caiwu; Wang, Chengdong; Li, Desheng; Lan, Jingchao; Zhang, Zhihe; Jing, Bo; Gu, Xiaobing; Xie, Yue; Lai, Weimin; Peng, Xuerong

2017-01-01

Baylisascaris schroederi is a common parasite of captive giant pandas. The diagnosis of this ascariasis is normally carried out by a sedimentation-floatation method or PCR to detect eggs in feces, but neither method is suitable for early diagnosis. Fatty acid-binding protein (FABP) and galectin (GAL) exist in various animals and participate in important biology of parasites. Because of their good immunogenicity, they are seen as potential antigens for the diagnosis of parasitic diseases. In this study, we cloned and expressed recombinant FABP and GAL from B. schroederi (rBs-FABP and rBs-GAL) and developed indirect enzyme-linked immunosorbent assays (ELISAs) to evaluate their potential for diagnosing ascariasis in giant pandas. Immunolocalization showed that Bs-FABP and Bs-GAL were widely distributed in adult worms. The ELISA based on rBs-FABP showed sensitivity of 95.8% (23/24) and specificity of 100% (12/12), and that based on rBs-GAL had sensitivity of 91.7% (22/24) and specificity of 100% (12/12). PMID:28750056

Over-expression of IQGAP1 indicates poor prognosis in head and neck squamous cell carcinoma.

PubMed

Wu, Cong-Cong; Li, Hao; Xiao, Yao; Yang, Lei-Lei; Chen, Lei; Deng, Wei-Wei; Wu, Lei; Zhang, Wen-Feng; Sun, Zhi-Jun

2018-05-30

IQ-domain GTPase-activating protein 1 (IQGAP1) is associated with the development and progression of many human cancers. We aimed to investigate the expression and clinicopathological significances of IQGAP1 in head and neck squamous cell carcinoma (HNSCC). In this study, immunohistochemical staining of IQGAP1, co-inhibitory immune checkpoint molecules and macrophage markers were performed in human HNSCC samples to analyze the expression and correlation with clinicopathological characteristics. Immunoreactivity of IQGAP1 was also detected in immunocompetent mouse HNSCC tissue. We found that IQGAP1 expression level was significantly increased in human HNSCC compared with dysplasia and normal mucosa, and the expression of IQGAP1 in HNSCC was positively associated with advanced lymph node status. Besides, our data indicated that patients with higher IQGAP1 expression exhibited poor overall survival compared with patients with lower IQGAP1 expression. Furthermore, this study demonstrated that IQGAP1 expression was positively associated with TIM3, Galectin-9 (TIM3 ligand), B7H4, macrophage markers CD68 and CD163. In conclusion, these findings suggest that over-expression of IQGAP1 in human HNSCC may indicate poor prognosis.

Glycogen synthase kinase 3 regulates PAX3-FKHR-mediated cell proliferation in human alveolar rhabdomyosarcoma cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeng, Fu-Yue; Dong, Hanqing; Cui, Jimmy

2010-01-01

Patients with alveolar rhabdomyosarcoma (ARMS) have poorer response to conventional chemotherapy and lower survival rates than those with embryonal RMS (ERMS). To identify compounds that preferentially block the growth of ARMS, we conducted a small-scale screen of 160 kinase inhibitors against the ARMS cell line Rh30 and ERMS cell line RD and identified inhibitors of glycogen synthase kinase 3 (GSK3), including TWS119 as ARMS-selective inhibitors. GSK3 inhibitors inhibited cell proliferation and induced apoptosis more effectively in Rh30 than RD cells. Ectopic expression of fusion protein PAX3-FKHR in RD cells significantly increased their sensitivity to TWS119. Down-regulation of GSK3 by GSK3more » inhibitors or siRNA significantly reduced the transcriptional activity of PAX3-FKHR. These results suggest that GSK3 is directly involved in regulating the transcriptional activity of PAX3-FKHR. Also, GSK3 phosphorylated PAX3-FKHR in vitro, suggesting that GSK3 might regulate PAX3-FKHR activity via phosphorylation. These findings support a novel mechanism of PAX3-FKHR regulation by GSK3 and provide a novel strategy to develop GSK inhibitors as anti-ARMS therapies.« less

Identification of highly selective and potent histone deacetylase 3 inhibitors using click chemistry-based combinatorial fragment assembly.

PubMed

Suzuki, Takayoshi; Kasuya, Yuki; Itoh, Yukihiro; Ota, Yosuke; Zhan, Peng; Asamitsu, Kaori; Nakagawa, Hidehiko; Okamoto, Takashi; Miyata, Naoki

2013-01-01

To find histone deacetylase 3 (HDAC3)-selective inhibitors, a series of 504 candidates was assembled using "click chemistry", by reacting nine alkynes bearing a zinc-binding group with 56 azide building blocks in the presence of Cu(I) catalyst. Screening of the 504-member triazole library against HDAC3 and other HDAC isozymes led to the identification of potent and selective HDAC3 inhibitors T247 and T326. These compounds showed potent HDAC3 inhibition with submicromolar IC50s, whereas they did not strongly inhibit other isozymes. Compounds T247 and T326 also induced a dose-dependent selective increase of NF-κB acetylation in human colon cancer HCT116 cells, indicating selective inhibition of HDAC3 in the cells. In addition, these HDAC3-selective inhibitors induced growth inhibition of cancer cells, and activated HIV gene expression in latent HIV-infected cells. These findings indicate that HDAC3-selective inhibitors are promising candidates for anticancer drugs and antiviral agents. This work also suggests the usefulness of the click chemistry approach to find isozyme-selective HDAC inhibitors.

Regulation of cytokine receptors by Golgi N-glycan processing and endocytosis.

PubMed

Partridge, Emily A; Le Roy, Christine; Di Guglielmo, Gianni M; Pawling, Judy; Cheung, Pam; Granovsky, Maria; Nabi, Ivan R; Wrana, Jeffrey L; Dennis, James W

2004-10-01

The Golgi enzyme beta1,6 N-acetylglucosaminyltransferase V (Mgat5) is up-regulated in carcinomas and promotes the substitution of N-glycan with poly N-acetyllactosamine, the preferred ligand for galectin-3 (Gal-3). Here, we report that expression of Mgat5 sensitized mouse cells to multiple cytokines. Gal-3 cross-linked Mgat5-modified N-glycans on epidermal growth factor and transforming growth factor-beta receptors at the cell surface and delayed their removal by constitutive endocytosis. Mgat5 expression in mammary carcinoma was rate limiting for cytokine signaling and consequently for epithelial-mesenchymal transition, cell motility, and tumor metastasis. Mgat5 also promoted cytokine-mediated leukocyte signaling, phagocytosis, and extravasation in vivo. Thus, conditional regulation of N-glycan processing drives synchronous modification of cytokine receptors, which balances their surface retention against loss via endocytosis.

Studies on the neuroprotective action of kynurenine mono-oxygenase inhibitors in post-ischemic brain damage.

PubMed

Moroni, Flavio; Carpenedo, Raffaella; Cozzi, Andrea; Meli, Elena; Chiarugi, Alberto; Pellegrini-Giampietro, Domenico E

2003-01-01

Kynurenine 3-mono-oxygenase (KMO) inhibitors facilitate kynurenic acid (KYNA) neosynthesis and reduce the formation of 3OH-kynurenine (3-HK) and quinolinic acid (QUIN). They also attenuate post-ischemic brain damage and decrease glutamate (Glu) content in brain extracellular spaces. To investigate KMO mechanism(s) of neuroprotection, we performed experiments in gerbils subjected to bilateral carotid occlusion and in organotypic rat hippocampal slice cultures exposed to oxygen and glucose deprivation (OGD). In gerbils, direct application of KYNA (100 nM, through reverse microdialysis in the hippocampus) completely prevented the increase in Glu output induced by transient (5 min) occlusion of the carotids. In rat hippocampal slices exposed for 30 min to OGD, KMO inhibitors (m-nitrobenzoyl)-alanine (mNBA, 30-100 microM) or 3,4-dimethoxy-[-N-4-(nitrophenyl)thiazol-2yl]-benzenesulfonamide (Ro 61-8048, 1-10 microM) reduced post-ischemic neuronal death and increased KYNA concentrations in the incubation medium. KYNA may antagonize glycineb or alpha7 nicotinic acetylcholine receptors but the concentrations in the incubation medium never reached values that could efficiently antagonize receptor function. On the contrary, 3-HK (1-10 microM) added to slices exposed to OGD in the presence of KMO inhibitors completely prevented the neuroprotective effects of the inhibitors. Our findings suggest that KMO inhibitors reduce OGD-induced pyramidal cell death by decreasing 3-HK (and possibly QUIN) synthesis.

Bonding the foe – NETting neutrophils immobilize the pro-inflammatory monosodium urate crystals

PubMed Central

Schorn, Christine; Janko, Christina; Krenn, Veit; Zhao, Yi; Munoz, Luis E.; Schett, Georg; Herrmann, Martin

2012-01-01

In the presence of sodium, uric acid from purine metabolism precipitates as monosodium urate (MSU) needles and forms renal calculi or causes gouty arthritis in kidneys and joints, respectively. The latter is characterized by red, hot, and swollen arthritic joints. Here we report the in vitro effect of MSU crystals on blood granulocytes and analyze their contribution to granuloma formation and neutrophil extracellular traps (NETs) formation (NETosis) in synovial fluid of patients with gouty arthritis in vivo. We observed that MSU crystals induce NETosis in vitro in a reactive oxygen species (ROS)-dependent manner. Indeed, blocking ROS (e.g., the oxidative burst) by various anti-oxidants partially inhibited NETosis induced by MSU crystals. Analyses of synovial fluids and of tissue sections of patients suffering from gout revealed that NETs are also formed in vivo, especially during acute gouty flares and/or granuloma formation. Since prolonged exposure to NETs carries the risk for the development of chronic inflammation we also studied the opsonization of NETs, as a prerequisite for their clearance. The established dead cells’ opsonins C3b, galectin-9, and CRP decorated the residual dead cells’ corpses and opsonized these for disposal. Surprisingly, all three soluble pattern recognizing molecules spared the spread NET structures. We conclude that (i) MSU crystals are strong inducers of ROS-dependent NETosis and (ii) that the prolonged presence of NET-pathogen or NET-crystal aggregates observed in patients with systemic autoimmunity, especially in those with low serum DNase-1 activity, cannot be compensated by CRP, complement, and galectin-mediated phagocytic clearance. PMID:23233855

Up-regulated expression of Tim-3/Gal-9 at maternal-fetal interface in pregnant woman with recurrent spontaneous abortion.

PubMed

Li, Jing; Li, Fan-fan; Zuo, Wei; Zhou, Yuan; Hao, Hai-yan; Dang, Jing; Jiang, Min; He, Meng-zhou; Deng, Dong-rui

2014-08-01

The relationship between T cell immunoglobulin domain and mucin domain protein 3 (Tim-3)/Galectin (Gal)-9 pathway and recurrent spontaneous abortion (RSA) was studied. Thirty-one pregnant women with RSA and 27 normal early gravidas were investigated to detect the levels of Tim-3 and Gal-9 in villi and deciduas by Western blotting. Meanwhile, the concentration of interleukin (IL)-4 and IL-12 in peripheral blood plasma was determined by ELISA in 25 healthy fertile non-pregnant controls, the normal early gravidas and pregnant women with RSA mentioned above, respectively. It was found that the relative expression levels of Tim-3 and Gal-9 in villi and deciduas were significantly increased in pregnant women with RSA as compared with those in the normal early gravidas. The concentration of IL-4 in peripheral blood plasma of pregnant women with RSA was lower than that of the normal early gravidas (P<0.05) and healthy fertile non-pregnant controls (P<0.05), but that of IL-2 in pregnant women with RSA was significantly higher than that of the normal early gravidas (P<0.05) and healthy fertile non-pregnant controls (P<0.05). It was suggested that the overexpression of Tim-3/Gal-9 pathway may be related to the pathogenesis of RSA.

A regulatory network of two galectins mediates the earliest steps of avian limb skeletal morphogenesis

PubMed Central

2011-01-01

Background The skeletal elements of vertebrate embryonic limbs are prefigured by rod- and spot-like condensations of precartilage mesenchymal cells. The formation of these condensations depends on cell-matrix and cell-cell interactions, but how they are initiated and patterned is as yet unresolved. Results Here we provide evidence that galectins, β-galactoside-binding lectins with β-sandwich folding, play fundamental roles in these processes. We show that among the five chicken galectin (CG) genes, two, CG-1A, and CG-8, are markedly elevated in expression at prospective sites of condensation in vitro and in vivo, with their protein products appearing earlier in development than any previously described marker. The two molecules enhance one another's gene expression but have opposite effects on condensation formation and cartilage development in vivo and in vitro: CG-1A, a non-covalent homodimer, promotes this process, while the tandem-repeat-type CG-8 antagonizes it. Correspondingly, knockdown of CG-1A inhibits the formation of skeletal elements while knockdown of CG-8 enhances it. The apparent paradox of mutual activation at the gene expression level coupled with antagonistic roles in skeletogenesis is resolved by analysis of the direct effect of the proteins on precartilage cells. Specifically, CG-1A causes their aggregation, whereas CG-8, which has no adhesive function of its own, blocks this effect. The developmental appearance and regulation of the unknown cell surface moieties ("ligands") to which CG-1A and CG-8 bind were indicative of specific cognate- and cross-regulatory interactions. Conclusion Our findings indicate that CG-1A and CG-8 constitute a multiscale network that is a major mediator, earlier-acting than any previously described, of the formation and patterning of precartilage mesenchymal condensations in the developing limb. This network functions autonomously of limb bud signaling centers or other limb bud positional cues. PMID:21284876

Metabolic responses in Candida tropicalis to complex inhibitors during xylitol bioconversion.

PubMed

Wang, Shizeng; Li, Hao; Fan, Xiaoguang; Zhang, Jingkun; Tang, Pingwah; Yuan, Qipeng

2015-09-01

During xylitol fermentation, Candida tropicalis is often inhibited by inhibitors in hemicellulose hydrolysate. The mechanisms involved in the metabolic responses to inhibitor stress and the resistances to inhibitors are still not clear. To understand the inhibition mechanisms and the metabolic responses to inhibitors, a GC/MS-based metabolomics approach was performed on C. tropicalis treated with and without complex inhibitors (CI, including furfural, phenol and acetic acid). Partial least squares discriminant analysis was used to determine the metabolic variability between CI-treated groups and control groups, and 25 metabolites were identified as possible entities responsible for the discrimination caused by inhibitors. We found that xylose uptake rate and xylitol oxidation rate were promoted by CI treatment. Metabolomics analysis showed that the flux from xylulose to pentose phosphate pathway increased, and tricarboxylic acid cycle was disturbed by CI. Moreover, the changes in levels of 1,3-propanediol, trehalose, saturated fatty acids and amino acids showed different mechanisms involved in metabolic responses to inhibitor stress. The increase of 1,3-propanediol was considered to be correlated with regulating redox balance and osmoregulation. The increase of trehalose might play a role in protein stabilization and cellular membranes protection. Saturated fatty acids could cause the decrease of membrane fluidity and make the plasma membrane rigid to maintain the integrity of plasma membrane. The deeper understanding of the inhibition mechanisms and the metabolic responses to inhibitors will provide us with more information on the metabolism regulation during xylitol bioconversion and the construction of industrial strains with inhibitor tolerance for better utilization of bioresource. Copyright © 2015 Elsevier Inc. All rights reserved.

A comparison of effects of DPP-4 inhibitor and SGLT2 inhibitor on lipid profile in patients with type 2 diabetes.

PubMed

Cha, Seon-Ah; Park, Yong-Moon; Yun, Jae-Seung; Lim, Tae-Seok; Song, Ki-Ho; Yoo, Ki-Dong; Ahn, Yu-Bae; Ko, Seung-Hyun

2017-04-13

Previous studies suggest that dipeptidyl peptidase-4 (DPP-4) inhibitors and sodium glucose cotransporter 2 (SGLT2) inhibitors have different effects on the lipid profile in patients with type 2 diabetes. We investigated the effects of DPP-4 inhibitors and SGLT2 inhibitors on the lipid profile in patients with type 2 diabetes. From January 2013 to December 2015, a total of 228 patients with type 2 diabetes who were receiving a DPP-4 inhibitor or SGLT2 inhibitor as add-on therapy to metformin and/or a sulfonylurea were consecutively enrolled. We compared the effects of DPP-4 inhibitors and SGLT2 inhibitors on the lipid profile at baseline and after 24 weeks of treatment. To compare lipid parameters between the two groups, we used the analysis of covariance (ANCOVA). A total of 184 patients completed follow-up (mean age: 53.1 ± 6.9 years, mean duration of diabetes: 7.1 ± 5.7 years). From baseline to 24 weeks, HDL-cholesterol (HDL-C) levels were increased by 0.5 (95% CI, -0.9 to 2.0) mg/dl with a DPP-4 inhibitor and by 5.1 (95% CI, 3.0 to 7.1) mg/dl with an SGLT2 inhibitor (p = 0.001). LDL-cholesterol (LDL-C) levels were reduced by 8.4 (95% CI, -14.0 to -2.8) mg/dl with a DPP-4 inhibitor, but increased by 1.3 (95% CI, -5.1 to 7.6) mg/dl with an SGLT2 inhibitor (p = 0.046). There was no significant difference in the mean hemoglobin A1c (8.3 ± 1.1 vs. 8.0 ± 0.9%, p = 0.110) and in the change of total cholesterol (TC) (p = 0.836), triglyceride (TG) (p = 0.867), apolipoprotein A (p = 0.726), apolipoprotein B (p = 0.660), and lipoprotein (a) (p = 0.991) between the DPP-4 inhibitor and the SGLT2 inhibitor. The SGLT2 inhibitor was associated with a significant increase in HDL-C and LDL-C after 24 weeks of SGLT2 inhibitor treatment in patients with type 2 diabetes compared with those with DPP-4 inhibitor treatment in this study. This study was conducted by retrospective medical record review.

Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid

NASA Astrophysics Data System (ADS)

Al-Amiery, Ahmed A.; Binti Kassim, Fatin A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

2016-01-01

The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10-3 M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir’s adsorption isotherm. The effect of temperature on corrosion behavior in the presence of 5 × 10-3 M inhibitor was studied in the temperature range of 30-60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl.

Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid

PubMed Central

Al-Amiery, Ahmed A.; Binti Kassim, Fatin A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

2016-01-01

The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10−3 M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir’s adsorption isotherm. The effect of temperature on corrosion behavior in the presence of 5 × 10−3 M inhibitor was studied in the temperature range of 30–60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl. PMID:26795066

Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid.

PubMed

Al-Amiery, Ahmed A; Binti Kassim, Fatin A; Kadhum, Abdul Amir H; Mohamad, Abu Bakar

2016-01-22

The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10(-3) M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir's adsorption isotherm. The effect of te perature on corrosion behavior in the presence of 5 × 10(-3) M inhibitor was studied in the temperature range of 30-60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl.

In vitro evaluation of the Aurora kinase inhibitor VX-680 for Hepatoblastoma.

PubMed

Dewerth, Alexander; Wonner, Timo; Lieber, Justus; Ellerkamp, Verena; Warmann, Steven W; Fuchs, Jörg; Armeanu-Ebinger, Sorin

2012-06-01

Hepatoblastoma (HB) has a poor prognosis in advanced stages. The aim of this study was to enhance effectiveness of chemotherapy with antineoplastic kinase inhibitors. Viability was monitored in HB cells (HUH6, HepT1) in monolayer and spheroid cultures treated with kinase inhibitors VX-680, Wee1-InhibitorII, and SU11274 alone or in combination with cisplatin (CDDP) using MTT assays. Apoptosis was revealed by Caspase-3 assay. Western blot and immunohistochemical analyses were performed to determine histone H3 phosphorylation. Among the kinase inhibitors strongest anti-proliferative effect on HB cells was documented for VX-680. HUH6 cells responded more sensitively to the Aurora kinase inhibitor as HepT1 cells (IC(50) 8 and 16.6 μM, respectively). While VX-680 and CDDP showed no additive effects, the combination of VX-680 and histone deacetylase inhibitor SAHA had a synergistic effect on the proliferation of HUH6 cells. The inhibition with VX-680 led to reduced histone H3 phosphorylation, to an increase of apoptotic cells, and to morphological changes such as vacuolization and swelling of the cells and nuclei. The data provide evidence that VX-680 might improve treatment results in HB with increased Aurora kinase activity by inhibiting cell proliferation and induction of apoptosis.

Ovalbumin Modified with Pyrraline, a Maillard Reaction Product, shows Enhanced T-cell Immunogenicity*

PubMed Central

Heilmann, Monika; Wellner, Anne; Gadermaier, Gabriele; Ilchmann, Anne; Briza, Peter; Krause, Maren; Nagai, Ryoji; Burgdorf, Sven; Scheurer, Stephan; Vieths, Stefan; Henle, Thomas; Toda, Masako

2014-01-01

The Maillard reaction (also referred to as “glycation”) takes place between reducing sugars and compounds with free amino groups during thermal processing of foods. In the final stage of the complex reaction cascade, the so-called advanced glycation end products (AGEs) are formed, including proteins with various glycation structures. It has been suggested that some AGEs could have immunostimulatory effects. Here, we aimed to identify specific glycation structure(s) that could influence the T-cell immunogenicity and potential allergenicity of food allergens, using ovalbumin (OVA, an egg white allergen) as a model allergen. OVA was specifically modified with representative glycation structures: Nϵ-carboxymethyl lysine (CM-OVA), Nϵ-carboxyethyl lysine (CE-OVA), pyrraline (Pyr-OVA), or methylglyoxal-derived arginine derivatives (MGO-OVA). As well as AGE-OVA, a crude glycation product in thermal incubation of OVA with glucose, only Pyr-OVA, and not other modified OVAs, was efficiently taken up by bone marrow-derived murine dendritic cells (BMDCs). The uptake of Pyr-OVA was reduced in scavenger receptor class A (SR-A)-deficient BMDCs, but not in cells treated with inhibitors of scavenger receptor class B, galectin-3, or blocking antibodies against CD36, suggesting that pyrraline binds to SR-A. Compared with other modified OVAs, Pyr-OVA induced higher activation of OVA-specific CD4+ T-cells in co-culture with BMDCs. Furthermore, compared with native OVA, AGE-OVA and Pyr-OVA induced higher IgE production in mice. Pyrraline could induce better allergen uptake by DCs via association with SR-A and subsequently enhance CD4+ T-cell activation and IgE production. Our findings help us to understand how Maillard reaction enhances the potential allergenicity of food allergens. PMID:24505139

Heme-Coordinating Inhibitors of Neuronal Nitric Oxide Synthase. Iron-Thioether Coordination is Stabilized by Hydrophobic Contacts Without Increased Inhibitor Potency

PubMed Central

Martell, Jeffrey D.; Li, Huiying; Doukov, Tzanko; Martásek, Pavel; Roman, Linda J.; Soltis, Michael; Poulos, Thomas L.; Silverman, Richard B.

2010-01-01

The heme-thioether ligand interaction often occurs between heme iron and native methionine ligands, but thioether-based heme-coordinating (type II) inhibitors are uncommon due to the difficulty in stabilizing the Fe-S bond. Here, a thioether-based inhibitor (3) of neuronal nitric oxide synthase (nNOS) was designed, and its binding was characterized by spectrophotometry and crystallography. A crystal structure of inhibitor 3 coordinated to heme iron was obtained, representing, to our knowledge, the first crystal structure of a thioether inhibitor complexed to any heme enzyme. A series of related potential inhibitors (4-8) also were evaluated. Compounds 4-8 were all found to be type I (non-heme-coordinating) inhibitors of ferric nNOS, but 4 and 6-8 were found to switch to type II upon heme reduction to the ferrous state, reflecting the higher affinity of thioethers for ferrous heme than for ferric heme. Contrary to what has been widely thought, thioether-heme ligation was found not to increase inhibitor potency, illustrating the intrinsic weakness of the thioether-ferric heme linkage. Subtle changes in the alkyl groups attached to the thioether sulfur caused drastic changes in binding conformation, indicating that hydrophobic contacts play a crucial role in stabilizing the thioether-heme coordination. PMID:20014790

Tumor vessel normalization by the PI3K inhibitor HS-173 enhances drug delivery.

PubMed

Kim, Soo Jung; Jung, Kyung Hee; Son, Mi Kwon; Park, Jung Hee; Yan, Hong Hua; Fang, Zhenghuan; Kang, Yeo Wool; Han, Boreum; Lim, Joo Han; Hong, Soon-Sun

2017-09-10

Tumor vessels are leaky and immature, which causes poor oxygen and nutrient supply to tumor vessels and results in cancer cell metastasis to distant organs. This instability of tumor blood vessels also makes it difficult for anticancer drugs to penetrate and reach tumors. Numerous tumor vessel normalization approaches have been investigated for improving drug delivery into tumors. In this study, we investigated whether phosphoinositide 3-kinase (PI3K) inhibitors are able to improve vascular structure and function over the prolonged period necessary to achieve effective vessel normalization. The PI3K inhibitors, HS-173 and BEZ235 potently suppressed tumor growth and hypoxia, and increased tumor apoptosis in animal models. PI3K inhibitors also induced a regular, flat monolayer of endothelial cells (ECs) in vessels, improving stability of vessel structure, and normalized tumor vessels by increasing vascular maturity, pericyte coverage, basement membrane thickness, and tight-junctions. These effects resulted in a decrease in tumor vessel tortuosity and vessel thinning, and improved vessel function and blood flow. The tumor vessel stabilization effect of the PI3K inhibitor HS-173 also decreased the number of metastatic lung nodules in vivo metastasis model. Furthermore, HS-173 improved the delivery of doxorubicin into the tumor region, enhancing its anticancer effects. Mechanistic studies suggested that PI3K inhibitor HS-173-induced vessel normalization reflected changes in endothelial Notch signaling. Taken together, our findings indicate that vessel normalization by PI3K inhibitors restrained tumor growth and metastasis while improving chemotherapy by enhancing drug delivery into the tumor, suggesting that HS-173 may have a therapeutic value as an enhancer or an anticancer drug. Copyright © 2017 Elsevier B.V. All rights reserved.

Sodium valproate, a histone deacetylase inhibitor, modulates the vascular endothelial growth inhibitor-mediated cell death in human osteosarcoma and vascular endothelial cells.

PubMed

Yamanegi, Koji; Kawabe, Mutsuki; Futani, Hiroyuki; Nishiura, Hiroshi; Yamada, Naoko; Kato-Kogoe, Nahoko; Kishimoto, Hiromitsu; Yoshiya, Shinichi; Nakasho, Keiji

2015-05-01

The level of vascular endothelial growth inhibitor (VEGI) has been reported to be negatively associated with neovascularization in malignant tumors. The soluble form of VEGI is a potent anti-angiogenic factor due to its effects in inhibiting endothelial cell proliferation. This inhibition is mediated by death receptor 3 (DR3), which contains a death domain in its cytoplasmic tail capable of inducing apoptosis that can be subsequently blocked by decoy receptor 3 (DcR3). We investigated the effects of sodium valproate (VPA) and trichostatin A (TSA), histone deacetylase inhibitors, on the expression of VEGI and its related receptors in human osteosarcoma (OS) cell lines and human microvascular endothelial (HMVE) cells. Consequently, treatment with VPA and TSA increased the VEGI and DR3 expression levels without inducing DcR3 production in the OS cell lines. In contrast, the effect on the HMVE cells was limited, with no evidence of growth inhibition or an increase in the DR3 and DcR3 expression. However, VPA-induced soluble VEGI in the OS cell culture medium markedly inhibited the vascular tube formation of HMVE cells, while VEGI overexpression resulted in enhanced OS cell death. Taken together, the HDAC inhibitor has anti-angiogenesis and antitumor activities that mediate soluble VEGI/DR3-induced apoptosis via both autocrine and paracrine pathways. This study indicates that the HDAC inhibitor may be exploited as a therapeutic strategy modulating the soluble VEGI/DR3 pathway in osteosarcoma patients.

Potentiation by cholinesterase inhibitors of cholinergic activity in rat isolated stomach and colon.

PubMed

Jarvie, Emma M; Cellek, Selim; Sanger, Gareth J

2008-01-01

Acetylcholinesterase (AChE) inhibitors stimulate gastrointestinal (GI) motility and are potential treatments of conditions associated with inadequate GI motility. The ability of itopride to facilitate neuronally (predominantly cholinergic) mediated contractions of rat isolated stomach, evoked by electrical field stimulation (EFS), has been compared with other cholinesterase inhibitors and with tegaserod, a clinically effective prokinetic and non-selective 5-HT(4) receptor agonist which also facilitates GI cholinergic function. Neostigmine greatly increased EFS-evoked contractions over a narrow concentration range (0.01-1 microM; 754+/-337% facilitation at 1 microM); higher concentrations (1, 3 microM) also increased muscle tension. Donepezil increased EFS-evoked contractions gradually over the full range of concentrations (0.01-10 microM; maximum increase 516+/-20% at 10 microM). Itopride increased the contractions even more gradually, rising to 188+/-84% at 10 microM. The butyrylcholinesterase inhibitor iso-OMPA 0.01-10 microM also increased EFS-evoked contractions, to a maximum of 36+/-5.0% at 10 microM, similar to that caused by tegaserod (35+/-5.2% increase at 1 microM). The effects of tegaserod, but not itopride were inhibited by the 5-HT(4) receptor antagonist SB-204070A 0.3 microM. In rat isolated colon, neostigmine was again the most efficacious, causing a defined maximum increase in EFS-evoked contractions (343+/-82% at 10 microM), without changing muscle tension. Maximum increases caused by donepezil and itopride were, respectively, 57.6+/-20 and 43+/-15% at 10 microM. These data indicate that the abilities of different AChE inhibitors to increase GI cholinergic activity differ markedly. Understanding the reasons is essential if AChE inhibitors are to be optimally developed as GI prokinetics.

Inhibitor of Nicotinamide Phosphoribosyltransferase Sensitizes Glioblastoma Cells to Temozolomide via Activating ROS/JNK Signaling Pathway.

PubMed

Feng, Jun; Yan, Peng-Fei; Zhao, Hong-Yang; Zhang, Fang-Cheng; Zhao, Wo-Hua; Feng, Min

2016-01-01

Overcoming temozolomide (TMZ) resistance is a great challenge in glioblastoma (GBM) treatment. Nicotinamide phosphoribosyltransferase (NAMPT) is a rate-limiting enzyme in the biosynthesis of nicotinamide adenine dinucleotide and has a crucial role in cancer cell metabolism. In this study, we investigated whether FK866 and CHS828, two specific NAMPT inhibitors, could sensitize GBM cells to TMZ. Low doses of FK866 and CHS828 (5 nM and 10 nM, resp.) alone did not significantly decrease cell viability in U251-MG and T98 GBM cells. However, they significantly increased the antitumor action of TMZ in these cells. In U251-MG cells, administration of NAMPT inhibitors increased the TMZ (100  μ M)-induced apoptosis and LDH release from GBM cells. NAMPT inhibitors remarkably enhanced the activities of caspase-1, caspase-3, and caspase-9. Moreover, NAMPT inhibitors increased reactive oxygen species (ROS) production and superoxide anion level but reduced the SOD activity and total antioxidative capacity in GBM cells. Treatment of NAMPT inhibitors increased phosphorylation of c-Jun and JNK. Administration of JNK inhibitor SP600125 or ROS scavenger tocopherol with TMZ and NAMPT inhibitors substantially attenuated the sensitization of NAMPT inhibitor on TMZ antitumor action. Our data indicate a potential value of NAMPT inhibitors in combined use with TMZ for GBM treatment.

Galectin-1-Driven Tolerogenic Programs Aggravate Yersinia enterocolitica Infection by Repressing Antibacterial Immunity.

PubMed

Davicino, Roberto C; Méndez-Huergo, Santiago P; Eliçabe, Ricardo J; Stupirski, Juan C; Autenrieth, Ingo; Di Genaro, María S; Rabinovich, Gabriel A

2017-08-15

Yersinia enterocolitica is an enteropathogenic bacterium that causes gastrointestinal disorders, as well as extraintestinal manifestations. To subvert the host's immune response, Y. enterocolitica uses a type III secretion system consisting of an injectisome and effector proteins, called Yersinia outer proteins (Yops), that modulate activation, signaling, and survival of immune cells. In this article, we show that galectin-1 (Gal-1), an immunoregulatory lectin widely expressed in mucosal tissues, contributes to Y. enterocolitica pathogenicity by undermining protective antibacterial responses. We found higher expression of Gal-1 in the spleen and Peyer's patches of mice infected orogastrically with Y. enterocolitica serotype O:8 compared with noninfected hosts. This effect was prevented when mice were infected with Y. enterocolitica lacking YopP or YopH, two critical effectors involved in bacterial immune evasion. Consistent with a regulatory role for this lectin during Y. enterocolitica pathogenesis, mice lacking Gal-1 showed increased weight and survival, lower bacterial load, and attenuated intestinal pathology compared with wild-type mice. These protective effects involved modulation of NF-κB activation, TNF production, and NO synthesis in mucosal tissue and macrophages, as well as systemic dysregulation of IL-17 and IFN-γ responses. In vivo neutralization of these proinflammatory cytokines impaired bacterial clearance and eliminated host protection conferred by Gal-1 deficiency. Finally, supplementation of recombinant Gal-1 in mice lacking Gal-1 or treatment of wild-type mice with a neutralizing anti-Gal-1 mAb confirmed the immune inhibitory role of this endogenous lectin during Y. enterocolitica infection. Thus, targeting Gal-1-glycan interactions may contribute to reinforce antibacterial responses by reprogramming innate and adaptive immune mechanisms. Copyright © 2017 by The American Association of Immunologists, Inc.

Natural single amino acid polymorphism (F19Y) in human galectin-8: detection of structural alterations and increased growth-regulatory activity on tumor cells.

PubMed

Ruiz, Federico M; Scholz, Barbara A; Buzamet, Eliza; Kopitz, Jürgen; André, Sabine; Menéndez, Margarita; Romero, Antonio; Solís, Dolores; Gabius, Hans-Joachim

2014-03-01

Natural amino acid substitution by single-site nucleotide polymorphism can become a valuable tool for structure-activity correlations, especially if evidence for association to disease parameters exists. Focusing on the F19Y change in human galectin-8, connected clinically to rheumatoid arthritis, we here initiate the study of consequences of a single-site substitution in the carbohydrate recognition domain of this family of cellular effectors. We apply a strategically combined set of structural and cell biological techniques for comparing properties of the wild-type and variant proteins. The overall hydrodynamic behavior of the full-length protein and of the separate N-domain is not noticeably altered, but displacements in the F0 β-strand of the β-sandwich fold in the N-domain are induced, as evidenced by protein crystallography. Analysis of thermal stability by circular dichroism spectroscopy revealed perceptible differences for the full-length proteins, pointing to an impact of the substitution beyond the N-domain. In addition, small differences in thermodynamic parameters of carbohydrate binding are detected. On the level of two types of tumor cells, characteristics of binding appeared rather similar. In further comparison of the influence on proliferation, the variant proved to be more active as growth regulator in the six tested lines of neuroblastoma, erythroleukemia and colon adenocarcinoma. The seemingly subtle structural change identified here thus has functional implications in vitro, encouraging further analysis in autoimmune regulation and, in a broad context, in work with other natural single-site variants, using the documented combined strategy. The atomic coordinates and structure factors (codes 4BMB, 4BME) have been deposited in the Protein Data Bank. © 2014 FEBS.

Silencing of galectin-1 inhibits retinal neovascularization and ameliorates retinal hypoxia in a murine model of oxygen-induced ischemic retinopathy.

PubMed

Yang, Ning; Zhang, Wenxi; He, Tao; Xing, Yiqiao

2017-06-01

Aberrant neovascularization is a consequence of inappropriate angiogenic signaling and contributes to several diseases. Although many regulators of pathogenic angiogenesis have been identified, the understanding of this process remains incomplete. Galectin-1 (Gal-1), as a homodimeric protein with a single carbohydrate-recognition domain, is implicated in several pathologic processes, including angiogenesis; however, its involvement in retinal neovascularization (RNV) remains unknown. Here, we investigated the anti-angiogenic effect of silencing Gal-1 through intravitreal injection in a mouse model of oxygen-induced retinopathy (OIR). Our results revealed that Gal-1 was overexpressed and closely related to retinal neo-vessels in OIR retinas. After silencing Gal-1 via intravitreal injection of adenoviral-Gal-1-RNA interference (Ad-Gal-1-RNAi), RNV and retinal hypoxia were significantly attenuated, indicating the anti-angiogenic effect of Gal-1 inhibition. Western blot analysis and real-time polymerase chain reaction indicated that the expression of both neuropilin-1 (Nrp-1) and B cell lymphoma-2 (Bcl-2) decreased after intravitreal injection of Ad-Gal-1-RNAi, implying the possible involvement of Nrp-1 and Bcl-2 in Gal-1-related angiogenic processes. Additionally, whole-mount fluorescence and hematoxylin and eosin staining showed that intravitreal injection of Ad-Gal-1-RNAi did not significantly disrupt the retinal vasculature and neuronal structure of room air mice. Moreover, Ad-Gal-1-RNAi transfer promoted retinal vascular sprouting and increased retinal vascular perfusion, likely through decreased phosphorylation of myosin phosphatase target protein-1. Collectively, our results demonstrated that Gal-1 functions as an important regulator in RNV and offers a promising strategy for the treatment of RNV diseases, such as proliferative diabetic retinopathy and retinopathy of prematurity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Novel Potential Interacting Partners of Fibronectin in Spontaneous Animal Model of Interstitial Cystitis

PubMed Central

Treutlein, Gudrun; Dorsch, Roswitha; Euler, Kerstin N.; Hauck, Stefanie M.; Amann, Barbara; Hartmann, Katrin; Deeg, Cornelia A.

2012-01-01

Feline idiopathic cystitis (FIC) is the only spontaneous animal model for human interstitial cystitis (IC), as both possess a distinctive chronical and relapsing character. Underlying pathomechanisms of both diseases are not clearly established yet. We recently detected increased urine fibronectin levels in FIC cases. The purpose of this study was to gain further insight into the pathogenesis by assessing interacting partners of fibronectin in urine of FIC affected cats. Several candidate proteins were identified via immunoprecipitation and mass spectrometry. Considerable changes in FIC conditions compared to physiological expression of co-purified proteins were detected by Western blot and immunohistochemistry. Compared to controls, complement C4a and thioredoxin were present in higher levels in urine of FIC patients whereas loss of signal intensity was detected in FIC affected tissue. Galectin-7 was exclusively detected in urine of FIC cats, pointing to an important role of this molecule in FIC pathogenesis. Moderate physiological signal intensity of galectin-7 in transitional epithelium shifted to distinct expression in transitional epithelium under pathophysiological conditions. I-FABP expression was reduced in urine and urinary bladder tissue of FIC cats. Additionally, transduction molecules of thioredoxin, NF-κB p65 and p38 MAPK, were examined. In FIC affected tissue, colocalization of thioredoxin and NF-κB p65 could be demonstrated compared to absent coexpression of thioredoxin and p38 MAPK. These considerable changes in expression level and pattern point to an important role for co-purified proteins of fibronectin and thioredoxin-regulated signal transduction pathways in FIC pathogenesis. These results could provide a promising starting point for novel therapeutic approaches in the future. PMID:23236492

Galectin-1 Prevents Infection and Damage Induced by Trypanosoma cruzi on Cardiac Cells

PubMed Central

Benatar, Alejandro F.; García, Gabriela A.; Bua, Jacqeline; Cerliani, Juan P.; Postan, Miriam; Tasso, Laura M.; Scaglione, Jorge; Stupirski, Juan C.; Toscano, Marta A.

2015-01-01

Background Chronic Chagas cardiomyopathy caused by Trypanosoma cruzi is the result of a pathologic process starting during the acute phase of parasite infection. Among different factors, the specific recognition of glycan structures by glycan-binding proteins from the parasite or from the mammalian host cells may play a critical role in the evolution of the infection. Methodology and Principal Findings Here we investigated the contribution of galectin–1 (Gal–1), an endogenous glycan-binding protein abundantly expressed in human and mouse heart, to the pathophysiology of T. cruzi infection, particularly in the context of cardiac pathology. We found that exposure of HL–1 cardiac cells to Gal–1 reduced the percentage of infection by two different T. cruzi strains, Tulahuén (TcVI) and Brazil (TcI). In addition, Gal–1 prevented exposure of phosphatidylserine and early events in the apoptotic program by parasite infection on HL–1 cells. These effects were not mediated by direct interaction with the parasite surface, suggesting that Gal–1 may act through binding to host cells. Moreover, we also observed that T. cruzi infection altered the glycophenotype of cardiac cells, reducing binding of exogenous Gal–1 to the cell surface. Consistent with these data, Gal–1 deficient (Lgals1 -/-) mice showed increased parasitemia, reduced signs of inflammation in heart and skeletal muscle tissues, and lower survival rates as compared to wild-type (WT) mice in response to intraperitoneal infection with T. cruzi Tulahuén strain. Conclusion/Significance Our results indicate that Gal–1 modulates T. cruzi infection of cardiac cells, highlighting the relevance of galectins and their ligands as regulators of host-parasite interactions. PMID:26451839

Toward a new and noninvasive diagnostic method of papillary thyroid cancer by using peptide vectorized contrast agents targeted to galectin-1.

PubMed

Fanfone, Deborah; Despretz, Nadège; Stanicki, Dimitri; Rubio-Magnieto, Jenifer; Fossépré, Mathieu; Surin, Mathieu; Rorive, Sandrine; Salmon, Isabelle; Vander Elst, Luce; Laurent, Sophie; Muller, Robert N; Saussez, Sven; Burtea, Carmen

2017-10-06

The incidence of papillary thyroid cancer has increased these last decades due to a better detection. High prevalence of nodules combined with the low incidence of thyroid cancers constitutes an important diagnostic challenge. We propose to develop an alternative diagnostic method to reduce the number of useless and painful thyroidectomies using a vectorized contrast agent for magnetic resonance imaging. Galectin-1 (gal-1), a protein overexpressed in well-differentiated thyroid cancer, has been targeted with a randomized linear 12-mer peptide library using the phage display technique. Selected peptides have been conjugated to ultrasmall superparamagnetic particles of iron oxide (USPIO). Peptides and their corresponding contrast agents have been tested in vitro for their specific binding and toxicity. Two peptides (P1 and P7) were selected according to their affinity toward gal-1. Their binding has been revealed by immunohistochemistry on human thyroid cancer biopsies, and they were co-localized with gal-1 by immunofluorescence on TPC-1 cell line. Both peptides induce a decrease in TPC-1 cells' adhesion to gal-1 immobilized on culture plates. After coupling to USPIO, the peptides preserved their affinity toward gal-1. Their specific binding has been corroborated by co-localization with gal-1 expressed by TPC-1 cells and by their ability to compete with anti-gal-1 antibody. The peptides and their USPIO derivatives produce no toxicity in HepaRG cells as determined by MTT assay. The vectorized contrast agents are potential imaging probes for thyroid cancer diagnosis. Moreover, the two gal-1-targeted peptides prevent cancer cell adhesion by interacting with the carbohydrate-recognition domain of gal-1.

Serum galectin-9 as a noninvasive biomarker for the detection of endometriosis and pelvic pain or infertility-related gynecologic disorders.

PubMed

Brubel, Reka; Bokor, Attila; Pohl, Akos; Schilli, Gabriella Krisztina; Szereday, Laszlo; Bacher-Szamuel, Reka; Rigo, Janos; Polgar, Beata

2017-12-01

To investigate the usefulness of soluble galectin-9 (Gal-9) in the noninvasive laboratory diagnosis of endometriosis and various gynecologic disorders. Prospective case-control study. University medical centers. A total of 135 women of reproductive age were involved in the study, 77 endometriosis patients, 28 gynecologic controls, and 30 healthy women. Diagnostic laparoscopy and collection of tissue biopsies, peritoneal cells, and native peripheral blood from different case groups of gynecology patients and healthy women. The expression of mRNA and serum concentration of Gal-9. Semiquantitative reverse transcription-polymerase chain reaction analysis and serum soluble Gal-9 ELISA were performed on three different cohorts of patients: those with endometriosis, those with benign gynecologic disorders, and healthy controls. Differences in the Gal-9 concentrations between the investigated groups and the stability of Gal-9 in the serum and diagnostic characteristics of Gal-9 ELISA were determined by statistical evaluation and receiver operating characteristic (ROC) curve analysis. Significantly elevated Gal-9 levels were found in both minimal-mild (I-II) and moderate-severe (III-IV) stages of endometriosis in comparison with healthy controls. At a cutoff of 132 pg/mL, ROC analysis revealed an excellent diagnostic value of Gal-9 ELISA in endometriosis (area under the curve = 0.973) with a sensitivity of 94% and specificity of 93.75%, indicating better diagnostic potential than that of other endometriosis biomarkers. Furthermore, various pelvic pain or infertility-associated benign gynecologic conditions were also associated with increased serum Gal-9 levels. Our results suggest that Gal-9 could be a promising noninvasive biomarker of endometriosis and a predictor of various infertility or pelvic pain-related gynecologic disorders. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Intermittent administration of MEK inhibitor GDC-0973 plus PI3K inhibitor GDC-0941 triggers robust apoptosis and tumor growth inhibition.

PubMed

Hoeflich, Klaus P; Merchant, Mark; Orr, Christine; Chan, Jocelyn; Den Otter, Doug; Berry, Leanne; Kasman, Ian; Koeppen, Hartmut; Rice, Ken; Yang, Nai-Ying; Engst, Stefan; Johnston, Stuart; Friedman, Lori S; Belvin, Marcia

2012-01-01

Combinations of MAP/ERK kinase (MEK) and phosphoinositide 3-kinase (PI3K) inhibitors have shown promise in preclinical cancer models, leading to the initiation of clinical trials cotargeting these two key cancer signaling pathways. GDC-0973, a novel selective MEK inhibitor, and GDC-0941, a class I PI3K inhibitor, are in early stage clinical trials as both single agents and in combination. The discovery of these selective inhibitors has allowed investigation into the precise effects of combining inhibitors of two major signaling branches downstream of RAS. Here, we investigated multiple biomarkers in the mitogen-activated protein kinase (MAPK) and PI3K pathway to search for points of convergence that explain the increased apoptosis seen in combination. Using washout studies in vitro and alternate dosing schedules in mice, we showed that intermittent inhibition of the PI3K and MAPK pathway is sufficient for efficacy in BRAF and KRAS mutant cancer cells. The combination of GDC-0973 with the PI3K inhibitor GDC-0941 resulted in combination efficacy in vitro and in vivo via induction of biomarkers associated with apoptosis, including Bcl-2 family proapoptotic regulators. Therefore, these data suggest that continuous exposure of MEK and PI3K inhibitors in combination is not required for efficacy in preclinical cancer models and that sustained effects on downstream apoptosis biomarkers can be observed in response to intermittent dosing. ©2011 AACR.

Omeprazole increases the efficacy of a soluble epoxide hydrolase inhibitor in a PGE{sub 2} induced pain model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goswami, Sumanta Kumar; Inceoglu, Bora; Yang, Jun

Epoxyeicosatrienoic acids (EETs) are potent endogenous analgesic metabolites produced from arachidonic acid by cytochrome P450s (P450s). Metabolism of EETs by soluble epoxide hydrolase (sEH) reduces their activity, while their stabilization by sEH inhibition decreases both inflammatory and neuropathic pain. Here, we tested the complementary hypothesis that increasing the level of EETs through induction of P450s by omeprazole (OME), can influence pain related signaling by itself, and potentiate the anti-hyperalgesic effect of sEH inhibitor. Rats were treated with OME (100 mg/kg/day, p.o., 7 days), sEH inhibitor TPPU (3 mg/kg/day, p.o.) and OME (100 mg/kg/day, p.o., 7 days) + TPPU (3 mg/kg/day,more » p.o., last 3 days of OME dose) dissolved in vehicle PEG400, and their effect on hyperalgesia (increased sensitivity to pain) induced by PGE{sub 2} was monitored. While OME treatment by itself exhibited variable effects on PGE{sub 2} induced hyperalgesia, it strongly potentiated the effect of TPPU in the same assay. The significant decrease in pain with OME + TPPU treatment correlated with the increased levels of EETs in plasma and increased activities of P450 1A1 and P450 1A2 in liver microsomes. The results show that reducing catabolism of EETs with a sEH inhibitor yielded a stronger analgesic effect than increasing generation of EETs by OME, and combination of both yielded the strongest pain reducing effect under the condition of this study. - Highlights: • The soluble epoxide hydrolase (sEH) inhibitor TPPU is anti-hyperalgesic. • Omeprazole potentiates the anti-hyperalgesic actions of TPPU. • This potentiation is associated with increased P450 activity. • The potentiation is associated with an increase in fatty acid epoxide/diol ratio. • Joint use of sEH inhibitors and P450 inducers could result in drug–drug interactions.« less

Macrophages as key elements of Mixed-oxide [U-Pu(O2)] distribution and pulmonary damage after inhalation?

PubMed

Van der Meeren, Anne; Moureau, Agnes; Griffiths, Nina M

2014-11-01

Abstract Purpose: To investigate the consequences of alveolar macrophage (AM) depletion on Mixed OXide fuel (MOX: U, Pu oxide) distribution and clearance, as well as lung damage following MOX inhalation. Rats were exposed to MOX by nose only inhalation. AM were depleted with intratracheal administration of liposomal clodronate at 6 weeks. Lung changes, macrophage activation, as well as local and systemic actinide distribution were studied up to 3 months post-inhalation. Clodronate administration modified excretion/retention patterns of α activity. At 3 months post-inhalation lung retention was higher in clodronate-treated rats compared to Phosphate Buffered Saline (PBS)-treated rats, and AM-associated α activity was also increased. Retention in liver was higher in clodronate-treated rats and fecal and urinary excretions were lower. Three months after inhalation, rats exhibited lung fibrotic lesions and alveolitis, with no marked differences between the two groups. Foamy macrophages of M2 subtype [inducible Nitric Oxide Synthase (iNOS) negative but galectin-3 positive] were frequently observed, in correlation with the accumulation of MOX particles. AM from all MOX-exposed rats showed increased chemokine levels as compared to sham controls. Despite the transient reduced AM numbers in clodronate-treated animals no major differences on lung damage were observed as compared to non-treated rats after MOX inhalation. The higher lung activity retention in rats receiving clodronate seems to be part of a general inflammatory response and needs further investigation.

Inhibitions of late INa and CaMKII act synergistically to prevent ATX-II-induced atrial fibrillation in isolated rat right atria.

PubMed

Liang, Faquan; Fan, Peidong; Jia, Jessie; Yang, Suya; Jiang, Zhan; Karpinski, Serge; Kornyeyev, Dmytro; Pagratis, Nikos; Belardinelli, Luiz; Yao, Lina

2016-05-01

Increases in late Na(+) current (late INa) and activation of Ca(2+)/calmodulin-dependent protein kinase (CaMKII) are associated with atrial arrhythmias. CaMKII also phosphorylates Nav1.5, further increasing late INa. The combination of a CaMKII inhibitor with a late INa inhibitor may be superior to each compound alone to suppress atrial arrhythmias. Therefore, we investigated the effect of a CaMKII inhibitor in combination with a late INa inhibitor on anemone toxin II (ATX-II, a late INa enhancer)-induced atrial arrhythmias. Rat right atrial tissue was isolated and preincubated with either the CaMKII inhibitor autocamtide-2-related inhibitory peptide (AIP), the late INa inhibitor GS458967, or both, and then exposed to ATX-II. ATX-II increased diastolic tension and caused fibrillation of isolated right atrial tissue. AIP (0.3μmol/L) and 0.1μmol/L GS458967 alone inhibited ATX-II-induced arrhythmias by 20±3% (mean±SEM, n=14) and 34±5% (n=13), respectively, whereas the two compounds in combination inhibited arrhythmias by 81±4% (n=10, p<0.05, vs either AIP or GS458967 alone or the calculated sum of individual effects of both compounds). AIP and GS458967 also attenuated the ATX-induced increase of diastolic tension. Consistent with the mechanical and electrical data, 0.3μmol/L AIP and 0.1μmol/L GS458967 each inhibited ATX-II-induced CaMKII phosphorylation by 23±3% and 32±4%, whereas the combination of both compounds inhibited CaMKII phosphorylation completely. The effects of an enhanced late INa to induce arrhythmic activity and activation of CaMKII in atria are attenuated synergistically by inhibitors of late INa and CaMKII. Copyright © 2016 Elsevier Ltd. All rights reserved.

Histone deacetylase inhibitors improve learning consolidation in young and in KA-induced-neurodegeneration and SAMP-8-mutant mice.

PubMed

Fontán-Lozano, Angela; Romero-Granados, Rocío; Troncoso, Julieta; Múnera, Alejandro; Delgado-García, José María; Carrión, Angel M

2008-10-01

Histone deacetylases (HDAC) are enzymes that maintain chromatin in a condensate state, related with absence of transcription. We have studied the role of HDAC on learning and memory processes. Both eyeblink classical conditioning (EBCC) and object recognition memory (ORM) induced an increase in histone H3 acetylation (Ac-H3). Systemic treatment with HDAC inhibitors improved cognitive processes in EBCC and in ORM tests. Immunohistochemistry and gene expression analyses indicated that administration of HDAC inhibitors decreased the stimulation threshold for Ac-H3, and gene expression to reach the levels required for learning and memory. Finally, we evaluated the effect of systemic administration of HDAC inhibitors to mice models of neurodegeneration and aging. HDAC inhibitors reversed learning and consolidation deficits in ORM in these models. These results point out HDAC inhibitors as candidate agents for the palliative treatment of learning and memory impairments in aging and in neurodegenerative disorders.

Protein-Glycan Quinary Interactions in Crowding Environment Unveiled by NMR Spectroscopy.

PubMed

Diniz, Ana; Dias, Jorge S; Jiménez-Barbero, Jesús; Marcelo, Filipa; Cabrita, Eurico J

2017-09-21

Protein-glycan interactions as modulators for quinary structures in crowding environments were explored. The interaction between human galectin 3 (Gal-3) and distinct macromolecular crowders, such as bovine and human serum albumin (BSA and HSA), Ficoll 70 and PEG3350, was scrutinized. The molecular recognition event of the specific ligand, lactose, by Gal-3 in crowding conditions was evaluated. Gal-3 interactions were monitored by NMR analysing chemical shift perturbation (CSP) and line broadening of 1 H 15 N-HSQC signals. The intensity of the Gal-3 1 H 15 N-HSQC signals decreased in the presence of all crowders, due to the increase in the solution viscosity and to the formation of large protein complexes. When glycosylated containing samples of BSA and HSA were used, signal broadening was more severe than that observed in the presence of the more viscous solutions of PEG3350 and Ficoll 70. However, for the samples containing glycoproteins, the signal intensity of 1 H 15 N-HSQC recovered upon addition of lactose. We show that serum proteins interact with Gal-3, through their α2,3-linked sialylgalactose moieties exposed at their surfaces, competing with lactose for the same binding site. The quinary interaction between Gal-3 and serum glycoproteins, could help to co-localize Gal-3 at the cell surface, and may play a role in adhesion and signalling functions of this protein. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

PI3K Inhibitors Synergize with FGFR Inhibitors to Enhance Antitumor Responses in FGFR2mutant Endometrial Cancers.

PubMed

Packer, Leisl M; Geng, Xinyan; Bonazzi, Vanessa F; Ju, Robert J; Mahon, Clare E; Cummings, Margaret C; Stephenson, Sally-Anne; Pollock, Pamela M

2017-04-01

Improved therapeutic approaches are needed for the treatment of recurrent and metastatic endometrial cancer. Endometrial cancers display hyperactivation of the MAPK and PI3K pathways, the result of somatic aberrations in genes such as FGFR2, KRAS, PTEN, PIK3CA , and PIK3R1 The FGFR2 and PI3K pathways, have emerged as potential therapeutic targets in endometrial cancer. Activation of the PI3K pathway is seen in more than 90% of FGFR2 mutant endometrial cancers. This study aimed to examine the efficacy of the pan-FGFR inhibitor BGJ398 with pan-PI3K inhibitors (GDC-0941, BKM120) and the p110α-selective inhibitor BYL719. We assessed synergy in three FGFR2 mutant endometrial cancer cell lines (AN3CA, JHUEM2, and MFE296), and the combination of BGJ398 and GDC-0941 or BYL719 showed strong synergy. A significant increase in cell death and decrease in long-term survival was seen when PI3K inhibitors were combined with BGJ398. Importantly, these effects were seen at low concentrations correlating to only partial inhibition of AKT. The combination of BGJ398 and GDC-0941 showed tumor regressions in vivo , whereas each drug alone only showed moderate tumor growth inhibition. BYL719 alone resulted in increased tumor growth of AN3CA xenografts but in combination with BGJ398 resulted in tumor regression in both AN3CA- and JHUEM2-derived xenografts. These data provide evidence that subtherapeutic doses of PI3K inhibitors enhance the efficacy of anti-FGFR therapies, and a combination therapy may represent a superior therapeutic treatment in patients with FGFR2 mutant endometrial cancer. Mol Cancer Ther; 16(4); 637-48. ©2017 AACR . ©2017 American Association for Cancer Research.

Bcl-2/Bcl-xL inhibition increases the efficacy of MEK inhibition alone and in combination with PI3 kinase inhibition in lung and pancreatic tumor models.

PubMed

Tan, Nguyen; Wong, Maureen; Nannini, Michelle A; Hong, Rebecca; Lee, Leslie B; Price, Stephen; Williams, Karen; Savy, Pierre Pascal; Yue, Peng; Sampath, Deepak; Settleman, Jeffrey; Fairbrother, Wayne J; Belmont, Lisa D

2013-06-01

Although mitogen-activated protein (MAP)-extracellular signal-regulated kinase (ERK) kinase (MEK) inhibition is predicted to cause cell death by stabilization of the proapoptotic BH3-only protein BIM, the induction of apoptosis is often modest. To determine if addition of a Bcl-2 family inhibitor could increase the efficacy of a MEK inhibitor, we evaluated a panel of 53 non-small cell lung cancer and pancreatic cancer cell lines with the combination of navitoclax (ABT-263), a Bcl-2/Bcl-xL (BCL2/BCL2L1) antagonist, and a novel MAP kinase (MEK) inhibitor, G-963. The combination is synergistic in the majority of lines, with an enrichment of cell lines harboring KRAS mutations in the high synergy group. Cells exposed to G-963 arrest in G1 and a small fraction undergo apoptosis. The addition of navitoclax to G-963 does not alter the kinetics of cell-cycle arrest, but greatly increases the percentage of cells that undergo apoptosis. The G-963/navitoclax combination was more effective than either single agent in the KRAS mutant H2122 xenograft model; BIM stabilization and PARP cleavage were observed in tumors, consistent with the mechanism of action observed in cell culture. Addition of the phosphatidylinositol 3-kinase (PI3K, PIK3CA) inhibitor GDC-0941 to this treatment combination increases cell killing compared with double- or single-agent treatment. Taken together, these data suggest the efficacy of agents that target the MAPK and PI3K pathways can be improved by combination with a Bcl-2 family inhibitor. ©2013 AACR

Acetylcholinesterase inhibitors rapidly activate Trk neurotrophin receptors in the mouse hippocampus

PubMed Central

Autio, Henri; Mätlik, Kert; Rantamäki, Tomi; Lindemann, Lothar; Hoener, Marius C; Chao, Moses; Arumäe, Urmas; Castrén, Eero

2014-01-01

Acetylcholinesterase inhibitors are first-line therapies for Alzheimer's disease. These drugs increase cholinergic tone in the target areas of the cholinergic neurons of the basal forebrain. Basal forebrain cholinergic neurons are dependent upon trophic support by nerve growth factor (NGF) through its neurotrophin receptor, TrkA. In the present study, we investigated whether the acetylcholinesterase inhibitors donepezil and galantamine could influence neurotrophin receptor signaling in the brain. Acute administration of donepezil (3 mg/kg, i.p.) led to the rapid autophosphorylation of TrkA and TrkB neurotrophin receptors in the adult mouse hippocampus. Similarly, galantamine dose-dependently (3, 9 mg/kg, i.p.) increased TrkA and TrkB phosphorylation in the mouse hippocampus. Both treatments also increased the phosphorylation of transcription factor CREB and tended to increase the phosphorylation of AKT kinase but did not alter the activity of MAPK42/44. Chronic treatment with galantamine (3 mg/kg, i.p., 14 days), did not induce changes in hippocampal NGF and BDNF synthesis or protein levels. Our findings show that acetylcholinesterase inhibitors are capable of rapidly activating hippocampal neurotrophin signaling and thus suggest that therapies targeting Trk signaling may already be in clinical use in the treatment of AD. PMID:21820453

Inhibitor effects of sodium benzoate on corrosion resistance of Al6061-B4C composites in NaCl and H3BO3 solutions

NASA Astrophysics Data System (ADS)

Rafi-ud-din; Shafqat, Q. A.; Shahzad, M.; Ahmad, Ejaz; Asghar, Z.; Rafiq, Nouman; Qureshi, A. H.; Syed, Waqar adil; asim Pasha, Riffat

2016-12-01

Sodium benzoate (SB) is used for the first time to inhibit the corrosion of Al6061-B4C composites in H3BO3 and NaCl solutions. Al6061100-x -x wt% B4C (x = 0, 5, and 10) composites are manufactured by a powder metallurgy route. The corrosion inhibition efficiency of SB is investigated as a function of the volume fractions of B4C particles by using potentiodynamic polarization and electrochemical impedance techniques. Without the use of an inhibitor, an increase of the B4C particles in the composite decreases the corrosion resistance of Al6061-B4C composites. It is found that SB is an efficient corrosion inhibitor for Al6061-B4C composites in both investigated solutions. The corrosion inhibition efficiency of SB increases with an increase in B4C content. Since SB is an adsorption type inhibitor, it is envisaged that an extremely thin layer of molecules adsorbs onto the surface and suppresses the oxidation and reduction. It is found that the inhibitor effect of SB is more pronounced in a H3BO3 environment than in NaCl solution. Further, the mechanism of corrosion inhibition by SB is illustrated by using optical and scanning electron microscopy of corroded samples. It is found that the adsorption of benzoate ions on the Al surface and its bonding with Al3+ ions forms a hydrophobic layer on top of the exposed Al surface, which enhances the protection against dissolved boride ions.

Wnt/β-catenin signaling inhibitor ICG-001 enhances pigmentation of cultured melanoma cells.

PubMed

Kim, Kyung-Il; Jeong, Do-Sun; Jung, Eui Chang; Lee, Jeung-Hoon; Kim, Chang Deok; Yoon, Tae-Jin

2016-11-01

Wnt/β-catenin signaling is important in development and differentiation of melanocytes. The object of this study was to evaluate the effects of several Wnt/β-catenin signaling inhibitors on pigmentation using melanoma cells. Melanoma cells were treated with Wnt/β-catenin signaling inhibitors, and then melanin content and tyrosinase activity were checked. Although some inhibitors showed slight inhibition of pigmentation, we failed to observe potential inhibitory effect of those chemicals on pigmentation of HM3KO melanoma cells. Rather, one of powerful Wnt/β-catenin signaling inhibitors, ICG-001, increased the pigmentation of HM3KO melanoma cells. Pigmentation-enhancing effect of ICG-001 was reproducible in other melanoma cell line MNT-1. Consistent with these results. ICG-001 increased the expression of pigmentation-related genes, such as MITF, tyrosinase and TRP1. When ICG-001 was treated, the phosphorylation of CREB was significantly increased. In addition, ICG-001 treatment led to quick increase of intracellular cAMP level, suggesting that ICG-001 activated PKA signaling. The blockage of PKA signaling with pharmaceutical inhibitor H89 inhibited the ICG-001-induced pigmentation significantly. These results suggest that PKA signaling is pivotal in pigmentation process itself, while the importance of Wnt/β-catenin signaling should be emphasized in the context of development and differentiation. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Triphenylethanamine Derivatives as Cholesteryl Ester Transfer Protein Inhibitors: Discovery of N-[(1R)-1-(3-Cyclopropoxy-4-fluorophenyl)-1-[3-fluoro-5-(1,1,2,2-tetrafluoroethoxy)phenyl]-2-phenylethyl]-4-fluoro-3-(trifluoromethyl)benzamide (BMS-795311).

PubMed

Qiao, Jennifer X; Wang, Tammy C; Adam, Leonard P; Chen, Alice Ye A; Taylor, David S; Yang, Richard Z; Zhuang, Shaobin; Sleph, Paul G; Li, Julia P; Li, Danshi; Yin, Xiaohong; Chang, Ming; Chen, Xue-Qing; Shen, Hong; Li, Jianqing; Smith, Daniel; Wu, Dauh-Rurng; Leith, Leslie; Harikrishnan, Lalgudi S; Kamau, Muthoni G; Miller, Michael M; Bilder, Donna; Rampulla, Richard; Li, Yi-Xin; Xu, Carrie; Lawrence, R Michael; Poss, Michael A; Levesque, Paul; Gordon, David A; Huang, Christine S; Finlay, Heather J; Wexler, Ruth R; Salvati, Mark E

2015-11-25

Cholesteryl ester transfer protein (CETP) inhibitors raise HDL-C in animals and humans and may be antiatherosclerotic by enhancing reverse cholesterol transport (RCT). In this article, we describe the lead optimization efforts resulting in the discovery of a series of triphenylethanamine (TPE) ureas and amides as potent and orally available CETP inhibitors. Compound 10g is a potent CETP inhibitor that maximally inhibited cholesteryl ester (CE) transfer activity at an oral dose of 1 mg/kg in human CETP/apoB-100 dual transgenic mice and increased HDL cholesterol content and size comparable to torcetrapib (1) in moderately-fat fed hamsters. In contrast to the off-target liabilities with 1, no blood pressure increase was observed with 10g in rat telemetry studies and no increase of aldosterone synthase (CYP11B2) was detected in H295R cells. On the basis of its preclinical profile, compound 10g was advanced into preclinical safety studies.

The inhibition of the kynurenine pathway prevents behavioral disturbances and oxidative stress in the brain of adult rats subjected to an animal model of schizophrenia.

PubMed

Réus, Gislaine Z; Becker, Indianara R T; Scaini, Giselli; Petronilho, Fabricia; Oses, Jean P; Kaddurah-Daouk, Rima; Ceretta, Luciane B; Zugno, Alexandra I; Dal-Pizzol, Felipe; Quevedo, João; Barichello, Tatiana

2018-02-02

Evidence has shown that the kynurenine pathway (KP) plays a role in the onset of oxidative stress and also in the pathophysiology of schizophrenia. The aim of this study was to use a pharmacological animal model of schizophrenia induced by ketamine to investigate if KP inhibitors could protect the brains of Wistar rats against oxidative stress and behavioral changes. Ketamine, injected at the dose of 25mg/kg, increased spontaneous locomotor activity. However, the inhibitors of tryptophan 2,3-dioxygenase (TDO), indoleamine 2,3-dioxygenase (IDO) and kynurenine-3-monooxygenase (KMO) were able to reverse these changes. In addition, the IDO inhibitor prevented lipid peroxidation, and decreased the levels of protein carbonyl in the prefrontal cortex (PFC), hippocampus and striatum. It also increased the activity of superoxide dismutase (SOD) in the hippocampus, as well as increasing the levels of catalase activity in the PFC and hippocampus. The TDO inhibitor prevented lipid damage in the striatum and reduced the levels of protein carbonyl in the hippocampus and striatum. Also, the TDO inhibitor increased the levels of SOD activity in the striatum and CAT activity in the hippocampus of ketamine-induced pro-oxidant effects. Lipid damage was not reversed by the KMO inhibitor. The KMO inhibitor increased the levels of SOD activity in the hippocampus, and reduced the levels of protein carbonyl while elevating the levels of CAT activity in the striatum of rats that had been injected with ketamine. Our findings revealed that the KP pathway could be a potential mechanism by which a schizophrenia animal model induced by ketamine could cause interference by producing behavioral disturbance and inducing oxidative stress in the brain, suggesting that the inhibition of the KP pathway could be a potential target in treating schizophrenia. Copyright © 2017 Elsevier Inc. All rights reserved.

Distinct apoptotic blocks mediate resistance to panHER inhibitors in HER2+ breast cancer cells.

PubMed

Karakas, Bahriye; Ozmay, Yeliz; Basaga, Huveyda; Gul, Ozgur; Kutuk, Ozgur

2018-05-04

Despite the development of novel targeted therapies, de novo or acquired chemoresistance remains a significant factor for treatment failure in breast cancer therapeutics. Neratinib and dacomitinib are irreversible panHER inhibitors, which block their autophosphorylation and downstream signaling. Moreover, neratinib and dacomitinib have been shown to activate cell death in HER2-overexpressing cell lines. Here we showed that increased MCL1 and decreased BIM and PUMA mediated resistance to neratinib in ZR-75-30 and SKBR3 cells while increased BCL-XL and BCL-2 and decreased BIM and PUMA promoted neratinib resistance in BT474 cells. Cells were also cross-resistant to dacomitinib. BH3 profiles of HER2+ breast cancer cells efficiently predicted antiapoptotic protein dependence and development of resistance to panHER inhibitors. Reactivation of ERK1/2 was primarily responsible for acquired resistance in SKBR3 and ZR-75-30 cells. Adding specific ERK1/2 inhibitor SCH772984 to neratinib or dacomitinib led to increased apoptotic response in neratinib-resistant SKBR3 and ZR-75-30 cells, but we did not detect a similar response in neratinib-resistant BT474 cells. Accordingly, suppression of BCL-2/BCL-XL by ABT-737 was required in addition to ERK1/2 inhibition for neratinib- or dacomitinib-induced apoptosis in neratinib-resistant BT474 cells. Our results showed that different mitochondrial apoptotic blocks mediated acquired panHER inhibitor resistance in HER2+ breast cancer cell lines as well as highlighted the potential of BH3 profiling assay in prediction of panHER inhibitor resistance in breast cancer cells. Copyright © 2018 Elsevier B.V. All rights reserved.

Study of caffeine as corrosion inhibitors of carbon steel in chloride solution containing hydrogen sulfide using electrochemical impedance spectroscopy (EIS)

NASA Astrophysics Data System (ADS)

Solehudin, Agus; Berman, Ega Taqwali; Nurdin, Isdiriayani

2015-09-01

The corrosion behaviour of steel surface in the absence and presence of caffeine in 3.5% NaCl solution containing dissolved H2S gas is studied using electrochemical impedance spectroscopy (EIS). The experimental results of carbon steel corrosion in 3.5% NaCl solution containing 500 mg/l H2S at different caffeine concentrations showed that corrosion rate of carbon steel decreases with increasing of caffeine concentrations from 0 to 0,1 mmol/l. Whereas, the corrosion rate increase with increasing of caffeine concentrations from 1 to 10 mmol/l. It is clear that no inhibition efficiency increases with increasing inhibitor concentration. The optimum value of inhibition efficiency was 90% at a caffeine concentration of 0.1 mmol/l. This suggests that caffeine's performance as a corrosion inhibitor is more effective at a concentration of 0.1 mmol/l.

Epigallocatechin-3-gallate increases intracellular [Ca2+] in U87 cells mainly by influx of extracellular Ca2+ and partly by release of intracellular stores.

PubMed

Kim, Hee Jung; Yum, Keun Sang; Sung, Jong-Ho; Rhie, Duck-Joo; Kim, Myung-Jun; Min, Do Sik; Hahn, Sang June; Kim, Myung-Suk; Jo, Yang-Hyeok; Yoon, Shin Hee

2004-02-01

Green tea has been receiving considerable attention as a possible preventive agent against cancer and cardiovascular disease. Epigallocatechin-3-gallate (EGCG) is a major polyphenol component of green tea. Using digital calcium imaging and an assay for [3H]-inositol phosphates, we determined whether EGCG increases intracellular [Ca2+] ([Ca2+]i) in non-excitable human astrocytoma U87 cells. EGCG induced concentration-dependent increases in [Ca2+]i. The EGCG-induced [Ca2+]i increases were reduced to 20.9% of control by removal of extracellular Ca2+. The increases were also inhibited markedly by treatment with the non-specific Ca2+ channel inhibitors cobalt (3 mM) for 3 min and lanthanum (1 mM) for 5 min. The increases were not significantly inhibited by treatment for 10 min with the L-type Ca2+ channel blocker nifedipine (100 nM). Treatment with the inhibitor of endoplasmic reticulum Ca2+-ATPase thapsigargin (1 micro M) also significantly inhibited the EGCG-induced [Ca2+]i increases. Treatment for 15 min with the phospholipase C (PLC) inhibitor neomycin (300 micro M) attenuated the increases significantly, while the tyrosine kinase inhibitor genistein (30 micro M) had no effect. EGCG increased [3H]-inositol phosphates formation via PLC activation. Treatment for 10 min with mefenamic acid (100 micro M) and flufenamic acid (100 micro M), derivatives of diphenylamine-2-carboxylate, blocked the EGCG-induced [Ca2+]i increase in non-treated and thapsigargin-treated cells but indomethacin (100 micro M) did not affect the increases. Collectively, these data suggest that EGCG increases [Ca2+]i in non-excitable U87 cells mainly by eliciting influx of extracellular Ca2+ and partly by mobilizing intracellular Ca2+ stores by PLC activation. The EGCG-induced [Ca2+]i influx is mediated mainly through channels sensitive to diphenylamine-2-carboxylate derivatives.

NAAG Peptidase Inhibitors Act via mGluR3: Animal Models of Memory, Alzheimer's, and Ethanol Intoxication.

PubMed

Olszewski, Rafal T; Janczura, Karolina J; Bzdega, Tomasz; Der, Elise K; Venzor, Faustino; O'Rourke, Brennen; Hark, Timothy J; Craddock, Kirsten E; Balasubramanian, Shankar; Moussa, Charbel; Neale, Joseph H

2017-09-01

Glutamate carboxypeptidase II (GCPII) inactivates the peptide neurotransmitter N-acetylaspartylglutamate (NAAG) following synaptic release. Inhibitors of GCPII increase extracellular NAAG levels and are efficacious in animal models of clinical disorders via NAAG activation of a group II metabotropic glutamate receptor. mGluR2 and mGluR3 knock-out (ko) mice were used to test the hypothesis that mGluR3 mediates the activity of GCPII inhibitors ZJ43 and 2-PMPA in animal models of memory and memory loss. Short- (1.5 h) and long- (24 h) term novel object recognition tests were used to assess memory. Treatment with ZJ43 or 2-PMPA prior to acquisition trials increased long-term memory in mGluR2, but not mGluR3, ko mice. Nine month-old triple transgenic Alzheimer's disease model mice exhibited impaired short-term novel object recognition memory that was rescued by treatment with a NAAG peptidase inhibitor. NAAG peptidase inhibitors and the group II mGluR agonist, LY354740, reversed the short-term memory deficit induced by acute ethanol administration in wild type mice. 2-PMPA also moderated the effect of ethanol on short-term memory in mGluR2 ko mice but failed to do so in mGluR3 ko mice. LY354740 and ZJ43 blocked ethanol-induced motor activation. Both GCPII inhibitors and LY354740 also significantly moderated the loss of motor coordination induced by 2.1 g/kg ethanol treatment. These data support the conclusion that inhibitors of glutamate carboxypeptidase II are efficacious in object recognition models of normal memory and memory deficits via an mGluR3 mediated process, actions that could have widespread clinical applications.

Phosphatidylinositol 3-Kinase (PI3K) δ blockade increases genomic instability in B cells

PubMed Central

Compagno, Mara; Wang, Qi; Pighi, Chiara; Cheong, Taek-Chin; Meng, Fei-Long; Poggio, Teresa; Yeap, Leng-Siew; Karaca, Elif; Blasco, Rafael B.; Langellotto, Fernanda; Ambrogio, Chiara; Voena, Claudia; Wiestner, Adrian; Kasar, Siddha N.; Brown, Jennifer R.; Sun, Jing; Wu, Catherine J.; Gostissa, Monica; Alt, Frederick W.; Chiarle, Roberto

2017-01-01

Activation-induced cytidine deaminase (AID) is a B-cell specific enzyme that targets immunoglobulin (Ig) genes to initiate class switch recombination (CSR) and somatic hypermutation (SHM)1. Through off-target activity, however, AID has a much broader impact on genomic instability by initiating oncogenic chromosomal translocations and mutations involved in lymphoma development and progression2. AID expression is tightly regulated in B cells and its overexpression leads to enhanced genomic instability and lymphoma formation3. The phosphatidylinositol 3-kinase (PI3K) δ pathway plays a key role in AID regulation by suppressing its expression in B cells4. Novel drugs for leukemia or lymphoma therapy such as idelalisib, duvelisib or ibrutinib block PI3Kδ activity directly or indirectly5–8, potentially affecting AID expression and, consequently, genomic stability in B cells. Here we show that treatment of primary mouse B cells with idelalisib or duvelisib, and to a lesser extent ibrutinib, enhanced the expression of AID and increased somatic hypermutation (SHM) and chromosomal translocation frequency to the Igh locus and to several AID off-target sites. Both these effects were completely abrogated in AID deficient B cells. PI3Kδ inhibitors or ibrutinib increased the formation of AID-dependent tumors in pristane-treated mice. Consistently, PI3Kδ inhibitors enhanced AID expression and translocation frequency to IgH and AID off-target sites in human chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) cell lines, and patients treated with idelalisib, but not ibrutinib, showed increased SHM in AID off-targets. In summary, we show that PI3Kδ or BTK inhibitors increase genomic instability in normal and neoplastic B cells by an AID-dependent mechanism, an effect that should be carefully considered as such inhibitors are administered for years to patients. PMID:28199309

Leptin-induced IL-6 production is mediated by leptin receptor, insulin receptor substrate-1, phosphatidylinositol 3-kinase, Akt, NF-kappaB, and p300 pathway in microglia.

PubMed

Tang, Chih-Hsin; Lu, Da-Yuu; Yang, Rong-Sen; Tsai, Huei-Yann; Kao, Ming-Ching; Fu, Wen-Mei; Chen, Yuh-Fung

2007-07-15

Leptin, the adipocyte-secreted hormone that centrally regulates weight control, is known to function as an immunomodulatory regulator. We investigated the signaling pathway involved in IL-6 production caused by leptin in microglia. Microglia expressed the long (OBRl) and short (OBRs) isoforms of the leptin receptor. Leptin caused concentration- and time-dependent increases in IL-6 production. Leptin-mediated IL-6 production was attenuated by OBRl receptor antisense oligonucleotide, PI3K inhibitor (Ly294002 and wortmannin), Akt inhibitor (1L-6-hydroxymethyl-chiro-inositol-2-((R)-2-O-methyl-3-O-octadecylcarbonate)), NF-kappaB inhibitor (pyrrolidine dithiocarbamate), IkappaB protease inhibitor (L-1-tosylamido-2-phenylenylethyl chloromethyl ketone), IkappaBalpha phosphorylation inhibitor (Bay 117082), or NF-kappaB inhibitor peptide. Transfection with insulin receptor substrate (IRS)-1 small-interference RNA or the dominant-negative mutant of p85 and Akt also inhibited the potentiating action of leptin. Stimulation of microglia with leptin activated IkappaB kinase alpha/IkappaB kinase beta, IkappaBalpha phosphorylation, IkappaBalpha degradation, p65 phosphorylation at Ser(276), p65 and p50 translocation from the cytosol to the nucleus, and kappaB-luciferase activity. Leptin-mediated an increase of IkappaB kinase alpha/IkappaB kinase beta activity, kappaB-luciferase activity, and p65 and p50 binding to the NF-kappaB element was inhibited by wortmannin, Akt inhibitor, and IRS-1 small-interference RNA. The binding of p65 and p50 to the NF-kappaB elements, as well as the recruitment of p300 and the enhancement of histone H3 and H4 acetylation on the IL-6 promoter was enhanced by leptin. Our results suggest that leptin increased IL-6 production in microglia via the leptin receptor/IRS-1/PI3K/Akt/NF-kappaB and p300 signaling pathway.

Loss of NEIL3 DNA glycosylase markedly increases replication associated double strand breaks and enhances sensitivity to ATR inhibitor in glioblastoma cells

PubMed Central

Klattenhoff, Alex W.; Thakur, Megha; Chu, Christopher S.; Ray, Debolina; Habib, Samy L.; Kidane, Dawit

2017-01-01

DNA endonuclease eight-like glycosylase 3 (NEIL3) is one of the DNA glycosylases that removes oxidized DNA base lesions from single-stranded DNA (ssDNA) and non-B DNA structures. Approximately seven percent of human tumors have an altered NEIL3 gene. However, the role of NEIL3 in replication-associated repair and its impact on modulating treatment response is not known. Here, we report that NEIL3 is localized at the DNA double-strand break (DSB) sites during oxidative DNA damage and replication stress. Loss of NEIL3 significantly increased spontaneous replication-associated DSBs and recruitment of replication protein A (RPA). In contrast, we observed a marked decrease in Rad51 on nascent DNA strands at the replication fork, suggesting that HR-dependent repair is compromised in NEIL3-deficient cells. Interestingly, NEIL3-deficient cells were sensitive to ataxia–telangiectasia and Rad3 related protein (ATR) inhibitor alone or in combination with PARP1 inhibitor. This study elucidates the mechanism by which NEIL3 is critical to overcome oxidative and replication-associated genotoxic stress. Our findings may have important clinical implications to utilize ATR and PARP1 inhibitors to enhance cytotoxicity in tumors that carry altered levels of NEIL3. PMID:29348879

Involvement of histidine residues in the pH-dependent β-galactoside binding activity of human galectin-1.

PubMed

Hiramatsu, Hirotsugu; Takeuchi, Katsuyuki; Takeuchi, Hideo

2013-04-02

The pH dependence of the β-galactoside binding activity of human galectin-1 (hGal-1) was investigated by fluorescence spectroscopy using lactose as a ligand. The obtained binding constant Kb was 2.94 ± 0.10 mM(-1) at pH 7.5. The Kb value decreased at acidic pH with a midpoint of transition at pH 6.0 ± 0.1. To elucidate the molecular mechanism of the pH dependence, we investigated the structures of hGal-1 and its two His mutants (H44Q and H52Q) using fluorescence, circular dichroism, UV absorption, and UV resonance Raman spectroscopy. Analysis of the spectra has shown that the pKa values of His44 and His52 are 5.7 ± 0.2 and 6.3 ± 0.1, respectively. The protonation of His52 below pH 6.3 induces a small change in secondary structure and partly reduces the galactoside binding activity. On the other hand, the protonation of His44 below pH 5.7 exerts a cation-π interaction with Trp68 and largely diminishes the galactoside binding activity. With reference to the literature X-ray structures at pH 7.0 and 5.6, protonated His52 is proposed to move slightly away from the galactoside-binding region with a partial unfolding of the β-strand containing His52. On the other hand, protonated His44 becomes unable to form a hydrogen bond with galactoside and additionally induces a reorientation and/or displacement of Trp68 through cation-π interaction, leading to a loosening of the galactoside-binding pocket. These structural changes associated with His protonation are likely to be the origin of the pH dependence of the galactoside binding activity of hGal-1.

Effects of cyclic structure inhibitors on the morphology and growth of tetrahydrofuran hydrate crystals

NASA Astrophysics Data System (ADS)

Li, Sijia; Wang, Yanhong; Lang, Xuemei; Fan, Shuanshi

2013-08-01

Morphology and growth of hydrate crystals with cyclic structure inhibitors at a hydrate-liquid interface were directly observed through a microscopic manipulating apparatus. Tetrahydrofuran (THF) hydrate was employed as an objective. The effects of four kind of cyclic structure inhibitors, polyvinylpyrrolidone (PVP), poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine) (PVPP), poly(2-vinyl pyridine-co-N-vinylcaprolactam) (PVPC) and poly(N-vinylcaprolactam) (PVCap), were investigated. Morphological patterns between each hydrate crystal growth from hydrate-liquid interface into droplet were found differ significantly. Lamellar structure growth of hydrate crystal was observed without inhibitor, while with PVP was featheriness-like, PVPP was like long dendritic crystal, PVPC was Mimosa pudica leaf-like and PVCap was like weeds. The growth rate of hydrate crystal without inhibitor was 0.00498 mm3/s, while with PVPP, PVPC and PVCap, were 0.00339 mm3/s, 0.00350 mm3/s, 0.00386 mm3/s and 0.00426 mm3/s, respectively. Cyclic structure inhibitors can decrease the growth rate, degree of reduction in growth rate of hydrate crystals decrease with the increase of cylinder number.

JAK2 inhibition sensitizes resistant EGFR-mutant lung adenocarcinoma to tyrosine kinase inhibitors

PubMed Central

Gao, Sizhi P.; Chang, Qing; Mao, Ninghui; Daly, Laura A.; Vogel, Robert; Chan, Tyler; Liu, Shu Hui; Bournazou, Eirini; Schori, Erez; Zhang, Haiying; Brewer, Monica Red; Pao, William; Morris, Luc; Ladanyi, Marc; Arcila, Maria; Manova-Todorova, Katia; de Stanchina, Elisa; Norton, Larry; Levine, Ross L.; Altan-Bonnet, Gregoire; Solit, David; Zinda, Michael; Huszar, Dennis; Lyden, David; Bromberg, Jacqueline F.

2016-01-01

Lung adenocarcinomas with mutant epidermal growth factor receptor (EGFR) respond to EGFR-targeted tyrosine kinase inhibitors (TKIs), but resistance invariably occurs. We found that the Janus kinase (JAK)/signal transduction and activator of transcription 3 (STAT3) signaling pathway was aberrantly increased in TKI-resistant EGFR-mutant non–small cell lung cancer (NSCLC) cells. JAK2 inhibition restored sensitivity to the EGFR inhibitor erlotinib in TKI-resistant cell lines and xenograft models of EGFR-mutant TKI-resistant lung cancer. JAK2 inhibition uncoupled EGFR from its negative regulator, suppressor of cytokine signaling 5 (SOCS5), consequently increasing EGFR abundance and restoring the tumor cells’ dependence on EGFR signaling. Furthermore, JAK2 inhibition led to heterodimerization of mutant and wild-type EGFR subunits, the activity of which was then blocked by TKIs. Our results reveal a mechanism whereby JAK2 inhibition overcomes acquired resistance to EGFR inhibitors and support the use of combination therapy with JAK and EGFR inhibitors for the treatment of EGFR-dependent NSCLC. PMID:27025877

Discovery of Selective, Substrate-Competitive, and Passive Membrane Permeable Glycogen Synthase Kinase-3β Inhibitors: Synthesis, Biological Evaluation, and Molecular Modeling of New C-Glycosylflavones.

PubMed

Liang, Zhibin; Li, Qing X

2018-05-16

Glycogen synthase kinase-3β (GSK-3β) is a key enzyme responsible for tau hyperphosphorylation and is a viable therapeutic target of Alzheimer's disease (AD). We developed a new class of GSK-3β inhibitors based on the 6- C-glycosylflavone isoorientin (1). The new inhibitors are passive membrane permeable and constitutively attenuate GSK-3β mediated tau hyperphosphorylation and amyloid neurotoxicity in an AD cellular model. Enzymatic assays and kinetic studies demonstrated that compound 30 is a GSK-3β substrate-competitive inhibitor with distinct kinase selectivity, isoform-selectivity and over 310-fold increased potency as compared to 1. Structure-activity relationship analyses and in silico modeling suggest the mechanism of actions by which the hydrophobic, π-cation, and orthogonal multipolar interactions of 30 with the substrate site are critical for the GSK-3β inhibition and selectivity. The results provide new insights into GSK-3β drug discovery. The new inhibitors are valuable chemical probes and drug leads with therapeutic potential to tackle AD and other GSK-3β relevant diseases.

Spatiotemporal Dynamics of Adenovirus Membrane Rupture and Endosomal Escape

PubMed Central

Maier, Oana; Marvin, Shauna A.; Wodrich, Harald; Campbell, Edward M.

2012-01-01

A key step in adenovirus cell entry is viral penetration of cellular membranes to gain access to the cytoplasm and deliver the genome to the nucleus. Yet little is known about this important event in the adenoviral life cycle. Using the cytosolic protein galectin-3 (gal3) as a marker of membrane rupture with both live- and fixed-cell imaging, we demonstrate that in the majority of instances, exposure of pVI and recruitment of gal3 to ruptured membranes occur early at or near the cell surface and occur minimally in EEA-1-positive (EEA-1+) early endosomes or LAMP-1+ late endosomes/lysosomes. Live-cell imaging of Ad5 egress from gal3+ endosomes occurs most frequently from perinuclear locations. While the Ad5 capsid is observed escaping from gal3+ endosomes, pVI appears to remain associated with the gal3+ ruptured endosomes. Thus, Ad5 membrane rupture and endosomal escape appear to be both spatially and temporally distinct events. PMID:22855481

Contribution of galectin-1, a glycan-binding protein, to gastrointestinal tumor progression.

PubMed

Bacigalupo, María L; Carabias, Pablo; Troncoso, María F

2017-08-07

Gastrointestinal cancer is a group of tumors that affect multiple sites of the digestive system, including the stomach, liver, colon and pancreas. These cancers are very aggressive and rapidly metastasize, thus identifying effective targets is crucial for treatment. Galectin-1 (Gal-1) belongs to a family of glycan-binding proteins, or lectins, with the ability to cross-link specific glycoconjugates. A variety of biological activities have been attributed to Gal-1 at different steps of tumor progression. Herein, we summarize the current literature regarding the roles of Gal-1 in gastrointestinal malignancies. Accumulating evidence shows that Gal-1 is drastically up-regulated in human gastric cancer, hepatocellular carcinoma, colorectal cancer and pancreatic ductal adenocarcinoma tissues, both in tumor epithelial and tumor-associated stromal cells. Moreover, Gal-1 makes a crucial contribution to the pathogenesis of gastrointestinal malignancies, favoring tumor development, aggressiveness, metastasis, immunosuppression and angiogenesis. We also highlight that alterations in Gal-1-specific glycoepitopes may be relevant for gastrointestinal cancer progression. Despite the findings obtained so far, further functional studies are still required. Elucidating the precise molecular mechanisms modulated by Gal-1 underlying gastrointestinal tumor progression, might lead to the development of novel Gal-1-based diagnostic methods and/or therapies.

Immunoregulatory protein B7-H3 promotes growth and decreases sensitivity to therapy in metastatic melanoma cells.

PubMed

Flem-Karlsen, Karine; Tekle, Christina; Andersson, Yvonne; Flatmark, Kjersti; Fodstad, Øystein; Nunes-Xavier, Caroline E

2017-09-01

B7-H3 (CD276) belongs to the B7 family of immunoregulatory proteins and has been implicated in cancer progression and metastasis. In this study, we found that metastatic melanoma cells with knockdown expression of B7-H3 showed modest decrease in proliferation and glycolytic capacity and were more sensitive to dacarbazine (DTIC) chemotherapy and small-molecule inhibitors targeting MAP kinase (MAPK) and AKT/mTOR pathways: vemurafenib (PLX4032; BRAF inhibitor), binimetinib (MEK-162; MEK inhibitor), everolimus (RAD001; mTOR inhibitor), and triciribidine (API-2; AKT inhibitor). Similar effects were observed in melanoma cells in the presence of an inhibitory B7-H3 monoclonal antibody, while the opposite was seen in B7-H3-overexpressing cells. Further, combining B7-H3 inhibition with small-molecule inhibitors resulted in significantly increased antiproliferative effect in melanoma cells, as well as in BRAF V 600E mutated cell lines derived from patient biopsies. Our findings indicate that targeting B7-H3 may be a novel alternative to improve current therapy of metastatic melanoma. © 2017 The Authors Pigment Cell & Melonoma Research Published by John Wiley & Sons Ltd.

[Influence of a new phosphoramide urease inhibitor on urea-N transformation in different texture soil].

PubMed

Zhou, Xuan; Wu, Liang Huan; Dai, Feng

2016-12-01

Addition of urease inhibitors is one of the important measures to increase nitrogen (N) use efficiency of crop, due to retardant of urea hydrolysis and reduction of ammonia volatilization loss. An incubation experiment was conducted to investigate the urease inhibition effect of a new phosphoramide urease inhibitor, NPPT (N-(n-propyl) thiophosphoric triamide) in different texture soils under dark condition at 25 ℃, and NBPT (N-(n-butyl) thiophosphoric triamide) was obtained to compare the inhibition effect on urease in different soil textures by different dosages of urea adding. Results showed that the effective reaction time of urea was less than 9 d in the loamy and clay soil. Addition of inhibitors for retardation of urea hydrolysis was more than 3 d. In sandy soil, urea decomposition was relatively slow, and adding inhibitor significantly inhibited soil urease acti-vity, and reduced NH 4 + -N content. During the incubation time, the inhibition effect of high dosage urea in the soil was better than that of low dosage. At day 6, the urease inhibition rate of NBPT and NPPT (N 250 mg·kg -1 ) were 56.3% and 53.0% in sandy soil, 0.04% and 0.3% in loamy soil, 4.1% and 6.2% in clay soil; the urease inhibition rate of NBPT and NPPT (N 500 mg·kg -1 ) were 59.4% and 65.8% in sandy soil, 14.5% and 15.1% in loamy soil, 49.1% and 48.1% in clay soil. The urease inhibition effects in different texture soil were in order of sandy soil > clay soil> loamy soil. The soil NH 4 + -N content by different inhibitors during incubation time increased at first and then decreased, while soil NO 3 - -N content and apparent nitrification rate both showed rising trends. Compared with urea treatment, addition of urease inhibitors (NBPT and NPPT) significantly increased urea-N left in the soil and reduced NH 4 + -N content. In short, new urease inhibitor NPPT in different texture is an effective urease inhibitor.

Preparation and biological evaluation of conformationally constrained BACE1 inhibitors.

PubMed

Winneroski, Leonard L; Schiffler, Matthew A; Erickson, Jon A; May, Patrick C; Monk, Scott A; Timm, David E; Audia, James E; Beck, James P; Boggs, Leonard N; Borders, Anthony R; Boyer, Robert D; Brier, Richard A; Hudziak, Kevin J; Klimkowski, Valentine J; Garcia Losada, Pablo; Mathes, Brian M; Stout, Stephanie L; Watson, Brian M; Mergott, Dustin J

2015-07-01

The BACE1 enzyme is a key target for Alzheimer's disease. During our BACE1 research efforts, fragment screening revealed that bicyclic thiazine 3 had low millimolar activity against BACE1. Analysis of the co-crystal structure of 3 suggested that potency could be increased through extension toward the S3 pocket and through conformational constraint of the thiazine core. Pursuit of S3-binding groups produced low micromolar inhibitor 6, which informed the S3-design for constrained analogs 7 and 8, themselves prepared via independent, multi-step synthetic routes. Biological characterization of BACE inhibitors 6-8 is described. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modular synthesis of amphiphilic Janus glycodendrimers and their self-assembly into glycodendrimersomes and other complex architectures with bioactivity to biomedically relevant lectins.

PubMed

Percec, Virgil; Leowanawat, Pawaret; Sun, Hao-Jan; Kulikov, Oleg; Nusbaum, Christopher D; Tran, Tam M; Bertin, Annabelle; Wilson, Daniela A; Peterca, Mihai; Zhang, Shaodong; Kamat, Neha P; Vargo, Kevin; Moock, Diana; Johnston, Eric D; Hammer, Daniel A; Pochan, Darrin J; Chen, Yingchao; Chabre, Yoann M; Shiao, Tze C; Bergeron-Brlek, Milan; André, Sabine; Roy, René; Gabius, Hans-J; Heiney, Paul A

2013-06-19

The modular synthesis of 7 libraries containing 51 self-assembling amphiphilic Janus dendrimers with the monosaccharides D-mannose and D-galactose and the disaccharide D-lactose in their hydrophilic part is reported. These unprecedented sugar-containing dendrimers are named amphiphilic Janus glycodendrimers. Their self-assembly by simple injection of THF or ethanol solution into water or buffer and by hydration was analyzed by a combination of methods including dynamic light scattering, confocal microscopy, cryogenic transmission electron microscopy, Fourier transform analysis, and micropipet-aspiration experiments to assess mechanical properties. These libraries revealed a diversity of hard and soft assemblies, including unilamellar spherical, polygonal, and tubular vesicles denoted glycodendrimersomes, aggregates of Janus glycodendrimers and rodlike micelles named glycodendrimer aggregates and glycodendrimermicelles, cubosomes denoted glycodendrimercubosomes, and solid lamellae. These assemblies are stable over time in water and in buffer, exhibit narrow molecular-weight distribution, and display dimensions that are programmable by the concentration of the solution from which they are injected. This study elaborated the molecular principles leading to single-type soft glycodendrimersomes assembled from amphiphilic Janus glycodendrimers. The multivalency of glycodendrimersomes with different sizes and their ligand bioactivity were demonstrated by selective agglutination with a diversity of sugar-binding protein receptors such as the plant lectins concanavalin A and the highly toxic mistletoe Viscum album L. agglutinin, the bacterial lectin PA-IL from Pseudomonas aeruginosa, and, of special biomedical relevance, human adhesion/growth-regulatory galectin-3 and galectin-4. These results demonstrated the candidacy of glycodendrimersomes as new mimics of biological membranes with programmable glycan ligand presentations, as supramolecular lectin blockers, vaccines, and targeted delivery devices.

Inhibition of Growth by Combined Treatment with Inhibitors of Lactate Dehydrogenase and either Phenformin or Inhibitors of 6-Phosphofructo-2-kinase/Fructose-2,6-bisphosphatase 3.

PubMed

Lea, Michael A; Guzman, Yolanda; Desbordes, Charles

2016-04-01

Enhanced glycolysis in cancer cells presents a target for chemotherapy. Previous studies have indicated that proliferation of cancer cells can be inhibited by treatment with phenformin and with an inhibitor of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB) namely 3-(3-pyridinyl)-1-(4-pyridinyl)-2-propen-1-one (3PO). In the present work, the action of two inhibitors that are effective at lower concentrations than 3PO, namely 1-(3-pyridinyl)-3-(2-quinolinyl)-2-propen-1-one (PQP) and 1-(4-pyridinyl)-3-(2-quinolinyl)-2-propen-1-one (PFK15) were investigated. The inhibitors of lactate dehydrogenase (LDHA) studied in order of half-maximal inhibitory concentrations were methyl 1-hydroxy-6-phenyl-4-(trifluoromethyl)-1H-indole-2-carboxylate (NHI-2) < isosafrole < oxamate. In colonic and bladder cancer cells, additive growth inhibitory effects were seen with the LDHA inhibitors, of which NHI-2 was effective at the lowest concentrations. Growth inhibition was generally greater with PFK15 than with PQP. The increased acidification of the culture medium and glucose uptake caused by phenformin was blocked by combined treatment with PFKFB3 or LDHA inhibitors. The results suggest that combined treatment with phenformin and inhibitors of glycolysis can cause additive inhibition of cell proliferation and may mitigate lactic acidosis caused by phenformin when used as a single agent. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Isoginkgetin inhibits tumor cell invasion by regulating phosphatidylinositol 3-kinase/Akt-dependent matrix metalloproteinase-9 expression.

PubMed

Yoon, Sang-Oh; Shin, Sejeong; Lee, Ho-Jae; Chun, Hyo-Kon; Chung, An-Sik

2006-11-01

Matrix metalloproteinase (MMP)-9 plays a key role in tumor invasion. Inhibitors of MMP-9 were screened from Metasequoia glyptostroboides (Dawn redwood) and one potent inhibitor, isoginkgetin, a biflavonoid, was identified. Noncytotoxic levels of isoginkgetin decreased MMP-9 production profoundly, but up-regulated the level of tissue inhibitor of metalloproteinase (TIMP)-1, an inhibitor of MMP-9, in HT1080 human fibrosarcoma cells. The major mechanism of Ras-dependent MMP-9 production in HT1080 cells was phosphatidylinositol 3-kinase (PI3K)/Akt/nuclear factor-kappaB (NF-kappaB) activation. Expression of dominant-active H-Ras and p85 (a subunit of PI3K) increased MMP-9 activity, whereas dominant-negative forms of these molecules decreased the level of MMP-9. H-Ras did not increase MMP-9 in the presence of a PI3K inhibitor, LY294002, and a NF-kappaB inhibitor, SN50. Further studies showed that isoginkgetin regulated MMP-9 production via PI3K/Akt/NF-kappaB pathway, as evidenced by the findings that isoginkgetin inhibited activities of both Akt and NF-kappaB. PI3K/Akt is a well-known key pathway for cell invasion, and isoginkgetin inhibited HT1080 tumor cell invasion substantially. Isoginkgetin was also quite effective in inhibiting the activities of Akt and MMP-9 in MDA-MB-231 breast carcinomas and B16F10 melanoma. Moreover, isoginkgetin treatment resulted in marked decrease in invasion of these cells. In summary, PI3K/Akt is a major pathway for MMP-9 expression and isoginkgetin markedly decreased MMP-9 expression and invasion through inhibition of this pathway. This suggests that isoginkgetin could be a potential candidate as a therapeutic agent against tumor invasion.

BAG3 regulates ECM accumulation in renal proximal tubular cells induced by TGF-β1.

PubMed

Du, Feng; Li, Si; Wang, Tian; Zhang, Hai-Yan; Li, De-Tian; Du, Zhen-Xian; Wang, Hua-Qin; Wang, Yan-Qiu

2015-01-01

Previously we have demonstrated that Bcl-2-associated athanogene 3 (BAG3) is increased in renal fibrosis using a rat unilateral ureteral obstruction model. The current study investigated the role of BAG3 in renal fibrosis using transforming growth factor (TGF)-β1-treated human proximal tubular epithelial (HK-2) cells. An upregulation of BAG3 in vitro models was observed, which correlated with the increased synthesis of extracellular matrix (ECM) proteins and expression of tissue-type plasminogen activator inhibitor (PAI)-1. Blockade of BAG3 induction by shorting hairpin RNA suppressed the expression of ECM proteins but had no effect on PAI-1 expression induced by TGF-β1. Forced overexpression of BAG3 selectively increased collagens. TGF-β1-induced BAG3 expression in HK-2 cells was attenuated by ERK1/2 and JNK MAPK inhibitors. In addition, forced BAG3 overexpression blocked attenuation of collagens expression by ERK1/2 and JNK inhibitors. These data suggest that ERK1/2 and JNK signaling events are involved in modulating the expression of BAG3, which would ultimately contribute to renal fibrosis by enhancing the synthesis and deposition of ECM proteins.

BAG3 regulates ECM accumulation in renal proximal tubular cells induced by TGF-β1

PubMed Central

Du, Feng; Li, Si; Wang, Tian; Zhang, Hai-Yan; Li, De-Tian; Du, Zhen-Xian; Wang, Hua-Qin; Wang, Yan-Qiu

2015-01-01

Previously we have demonstrated that Bcl-2-associated athanogene 3 (BAG3) is increased in renal fibrosis using a rat unilateral ureteral obstruction model. The current study investigated the role of BAG3 in renal fibrosis using transforming growth factor (TGF)-β1-treated human proximal tubular epithelial (HK-2) cells. An upregulation of BAG3 in vitro models was observed, which correlated with the increased synthesis of extracellular matrix (ECM) proteins and expression of tissue-type plasminogen activator inhibitor (PAI)-1. Blockade of BAG3 induction by shorting hairpin RNA suppressed the expression of ECM proteins but had no effect on PAI-1 expression induced by TGF-β1. Forced overexpression of BAG3 selectively increased collagens. TGF-β1-induced BAG3 expression in HK-2 cells was attenuated by ERK1/2 and JNK MAPK inhibitors. In addition, forced BAG3 overexpression blocked attenuation of collagens expression by ERK1/2 and JNK inhibitors. These data suggest that ERK1/2 and JNK signaling events are involved in modulating the expression of BAG3, which would ultimately contribute to renal fibrosis by enhancing the synthesis and deposition of ECM proteins. PMID:26885277

Development of new corrosion inhibitor tested on mild steel supported by electrochemical study

NASA Astrophysics Data System (ADS)

Habeeb, Hussein Jwad; Luaibi, Hasan Mohammed; Dakhil, Rifaat Mohammed; Kadhum, Abdul Amir H.; Al-Amiery, Ahmed A.; Gaaz, Tayser Sumer

2018-03-01

Mild steel is a metal which is commonly used in industrials and manufacturing of equipment for most industries round the world. It is cheaper cost compared with the other metals and its durable, hard and easy-to-wear physical properties make it a major choice in the manufacture of equipment parts. The main problem through the uses of mild steel in industry is its resistance against corrosion, especially in acidic solutions. This case led to raise the cost of maintenance of equipment that used mild steel and as a result increased costs for the company. Organic corrosive inhibitors that also act as green chemicals, 4-hydroxybenzylideneaminomethyl-5-ethyl-1,3,4-thiadiazol have been synthesized. This inhibitor is tested as corrosion inhibitor on a mild steel sample MS in 1 M hydrochloric acid solution (HCl) using electrochemical measurements test includes PD (Potentiodynamic), EIS (Electrochemical impedance spectroscopy), OCP (Open circuit potential) and EFM (electrochemical frequency modulation). The obtained results indicate that 4-hydroxybenzylideneaminomethyl-5-ethyl-1,3,4-thiadiazol acts as a good corrosion inhibitor for mild steel sample in HCl solution with efficiency above 90%. Changes in the impedance parameters postulated adsorption on the mild steel specimens' surfaces of, which it going to the formation of protective coating layer. It also shows that 4-hydroxybenzylideneaminomethyl-5-ethyl-1,3,4-thiadiazol corrosion inhibitors are effective in helping to reduce and slow down the corrosion process that occurs on mild steel surface in hydrochloric acid solution. Increase of corrosion inhibitor concentration provides a protective layer of mild steel. However, this protective layer becomes weak when the temperature of the solution increases.

Group I mGluR-Regulated Translation of the Neuronal Glutamate Transporter, Excitatory Amino Acid Carrier 1 (EAAC1)

PubMed Central

Ross, John R.; Ramakrishnan, Hariharasubramanian; Porter, Brenda E.; Robinson, Michael B.

2011-01-01

Recently, we demonstrated that mRNA for the neuronal glutamate transporter, excitatory amino acid carrier 1 (EAAC1), is found in dendrites of hippocampal neurons in culture and in dendrites of hippocampal pyramidal cells after pilocarpine-induced status epilepticus (SE). We also showed that SE increased the levels of EAAC1 mRNA ~15-fold in synaptoneurosomes. In the present study, the effects of SE on the distribution EAAC1 protein in hippocampus were examined. In addition, the effects of Group 1 mGluR receptor activation on the levels of EAAC1 protein were examined in synaptoneurosomes prepared from sham control animals and from animals that experience pilocarpine-induced SE. We find that EAAC1 immunoreactivity increases in pyramidal cells of the hippocampus after 3 h of SE. In addition, the group I mGluR agonist, (S)-3,5-dihydroxyphenylglycine (DHPG), caused an increase in EAAC1 protein levels in hippocampal synaptoneurosomes; this effect of DHPG was much larger (~3- to 5-fold) after 3 h of SE. The DHPG-induced increases in EAAC1 protein were blocked by two different inhibitors of translation but not by inhibitors of transcription. mGluR1 or mGluR5 antagonists completely blocked the DHPG-induced increases in EAAC1 protein. DHPG also increased the levels of GluR2/3 protein, but this effect was not altered by SE. The DHPG-induced increase in EAAC1 protein was blocked by an inhibitor of the mammalian target of rapamycin (mTOR) or an inhibitor of extracellular signal-regulated kinase (ERK). These studies provide the first evidence EAAC1 translation can be regulated, and they show that regulated translation of EAAC1 is up-regulated after SE. PMID:21371038

Inhibitors of soluble epoxide hydrolase minimize ischemia-reperfusion-induced cardiac damage in normal, hypertensive, and diabetic rats.

PubMed

Islam, Oliul; Patil, Prashanth; Goswami, Sumanta K; Razdan, Rema; Inamdar, Mohammed N; Rizwan, Mohammed; Mathew, Jubin; Inceoglu, Bora; Stephen Lee, Kin S; Hwang, Sung H; Hammock, Bruce D

2017-06-01

We designed a study to evaluate the cardioprotective effect of two soluble epoxide hydrolase (sEH) inhibitors, 1-(1-propanoylpiperidin-4-yl)-3-(4-trifluoromethoxy)phenyl)urea (TPPU) and trans-4-{4-[3-(4-trifluoromethoxyphenyl)-ureido]cyclohexyloxy}benzoic acid (t-TUCB), in ischemia-reperfusion (IR) model. Cardioprotective effects of the sEH inhibitors were evaluated against IR-induced myocardial damage in hearts from normal, hypertensive, and diabetic rats using Langendorff's apparatus. In addition, the effect of sEH inhibitors on endothelial function was evaluated in vitro and ex vivo using isolated rat thoracic aorta. Ischemia-reperfusion (IR) increased the myocardial damage in hearts from normal rats. IR-induced myocardial damage was augmented in hearts isolated from hypertensive and diabetic rats. Myocardial damage as evident from increase in the activities of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) in heart perfusate was associated with significant decrease in the heart rate and developed tension, and increase in the resting tension in isolated heart. Both sEH inhibitors protected the heart in normal, hypertensive, and diabetic rats subjected to IR injury. The sEH inhibitor t-TUCB relaxed phenylephrine precontracted aorta from normal rats. Relaxant effect of acetylcholine (ACh) was reduced in aortas from diabetic and hypertensive rats compared to normal rats. Pretreatment of sEH inhibitors to diabetic and hypertensive rats increased relaxant effect of ACh on aortas isolated from these rats. Prophylactic treatment with sEH inhibitors decreased myocardial damage due to IR, hypertension and diabetes, and decreased endothelial dysfunction created by diabetes and hypertension. Therefore, inhibitors of sEH are useful probes to study cardiovascular pathology, and inhibition of the sEH is a potential approach in the management of IR-induced cardiac damage and endothelial dysfunction-related cardiovascular disorders. © 2017 John Wiley & Sons Ltd.

3,4-Dihydroxyphenylethanol (Hydroxytyrosol) Mitigates the Increase in Spontaneous Oxidation of Dopamine during Monoamine Oxidase Inhibition in PC12 Cells

PubMed Central

Goldstein, David S.; Jinsmaa, Yunden; Sullivan, Patti; Holmes, Courtney; Kopin, Irwin J.; Sharabi, Yehonatan

2016-01-01

The catecholaldehyde hypothesis predicts that monoamine oxidase (MAO) inhibition should slow the progression of Parkinson’s disease, by decreasing production of the autotoxic dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL). Inhibiting MAO, however, diverts the fate of cytoplasmic dopamine toward potentially harmful spontaneous oxidation products, indicated by increased 5-S-cysteinyl-dopamine (Cys-DA) levels. 3,4-Dihydroxyphenylethanol (hydroxytyrosol) is an abundant anti-oxidant phenol in constituents of the Mediterranean diet. Whether hydroxytyrosol alters enzymatic or spontaneous oxidation of dopamine has been unknown. Rat pheochromocytoma PC12 cells were incubated with hydroxytyrosol (10 μM, 180 minutes) alone or with the MAO-A inhibitor clorgyline (1 nM) or the MAO-B inhibitors rasagiline or selegiline (0.5 μM). Hydroxytyrosol decreased levels of DOPAL by 30% and Cys-DA by 49% (p<0.0001 each). Co-incubation with hydroxytyrosol prevented the increases in Cys-DA seen with all 3 MAO inhibitors. Hydroxytyrosol therefore inhibits both enzymatic and spontaneous oxidation of endogenous dopamine and mitigates the increase in spontaneous oxidation during MAO inhibition. PMID:27220335

Reciprocal feedback inhibition of the androgen receptor and PI3K as a novel therapy for castrate-sensitive and -resistant prostate cancer.

PubMed

Qi, Wenqing; Morales, Carla; Cooke, Laurence S; Johnson, Benny; Somer, Bradley; Mahadevan, Daruka

2015-12-08

Gain-of-function of the androgen receptor (AR) and activation of PI3K/AKT/mTOR pathway have been demonstrated to correlate with progression to castration-resistant prostate cancer (CRPC). However, inhibition of AR or PI3K/mTOR alone results in a reciprocal feedback activation. Therefore, we hypothesized that dual inhibition of the AR and PI3K/mTOR pathway might lead to a synergistic inhibition of cell growth and overcome drug resistance in CRPC. Here, we reported that androgen-depletion increased AR protein level and Akt phosphorylation at Ser473 and Thr308 in LNCaP cells. Moreover, we developed resistance cell lines of LNCaP to Enzalutamide (or MDV3100), an AR inhibitor (named as LNCaP 'MDV-R') and PF-04691502, a PI3K/mTOR inhibitor (named as LNCaP 'PF-R'). MTS analysis showed that LNCaP 'PF-R' was strongly resistant to Enzalutamide treatment, and on the other hand, LNCaP 'MDV-R' was 6-fold resistant to PF-04691502 treatment. Mechanistically, LNCaP 'MDV-R' cells had significantly reduced AR, loss of PSA and increase Akt activity in contrast with LNCaP 'PF-R' cells. Combined inhibition of PI3K/mTOR and AR pathways with a variety of small molecular inhibitors led to a synergistic suppression of cell proliferation and a profound increase of apoptosis and cell cycle arrest in both androgen-dependent LNCaP and independent CRPC 22Rv1 cell lines. In conclusion, this study provides preclinical proof-of-concept that the combination of a PI3K/mTOR inhibitor with an AR inhibitor results in a synergistic anti-tumor response in non-CRPC and CRPC models.