- MeSH
- beta-Galactosidase metabolism MeSH
- Rabbits MeSH
- Corneal Injuries MeSH
- Cornea enzymology pathology MeSH
- Substrate Specificity MeSH
- Animals MeSH
- Check Tag
- Rabbits MeSH
- Animals MeSH
- Publication type
- Comparative Study MeSH
- MeSH
- Hydrocortisone pharmacology MeSH
- Rats MeSH
- RNA, Messenger metabolism drug effects MeSH
- Mifepristone pharmacology MeSH
- Receptors, Glucocorticoid metabolism drug effects MeSH
- Sucking Behavior drug effects MeSH
- Sialyltransferases genetics metabolism drug effects MeSH
- Pregnancy MeSH
- Intestine, Small enzymology drug effects MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Pregnancy MeSH
- Animals MeSH
Galectins are lectins that bind β-galactosides. They are involved in important extra- and intracellular biological processes such as apoptosis, and regulation of the immune system or the cell cycle. High-affinity ligands of galectins may introduce new therapeutic approaches or become new tools for biomedical research. One way of increasing the low affinity of β-galactoside ligands to galectins is their multivalent presentation, e.g., using calixarenes. We report on the synthesis of glycocalix[4]arenes in cone, partial cone, 1,2-alternate, and 1,3-alternate conformations carrying a lactosyl ligand on three different linkers. The affinity of the prepared compounds to a library of human galectins was determined using competitive ELISA assay and biolayer interferometry. Structure-affinity relationships regarding the influence of the linker and the core structure were formulated. Substantial differences were found between various linker lengths and the position of the triazole unit. The formation of supramolecular clusters was detected by atomic force microscopy. The present work gives a systematic insight into prospective galectin ligands based on the calix[4]arene core.
- MeSH
- Galectins * chemistry MeSH
- Glycocalyx * MeSH
- Humans MeSH
- Ligands MeSH
- Molecular Conformation MeSH
- Prospective Studies MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Understanding the molecular and cellular processes in skin wound healing can pave the way for devising innovative concepts by turning the identified natural effectors into therapeutic tools. Based on the concept of broad‐scale engagement of members of the family of galactoside‐binding lectins (galectins) in pathophysiological processes, such as cancer or tissue repair/regeneration, the present study investigated the potential of galectins‐1 (Gal‐1) and ‐3 (Gal‐3) in wound healing. Human dermal fibroblasts, which are key cells involved in skin wound healing, responded to galectin exposure (Gal‐1 at 300 or Gal‐3 at 600 ng/ml) with selective changes in gene expression among a panel of 84 wound‐healing‐related genes, as well as remodeling of the extracellular matrix. In the case of Gal‐3, positive expression of Ki67 and cell number increased when using a decellularized matrix produced by Gal‐3‐treated fibroblasts as substrate for culture of interfollicular keratinocytes. In vivo wounds were topically treated with 20 ng/ml Gal‐1 or ‐3, and collagen score was found to be elevated in excisional wound repair in rats treated with Gal‐3. The tensile strength measured in incisions was significantly increased from 79.5±17.5 g/mm2 in controls to 103.1±21.4 g/mm2 after 21 days of healing. These data warrant further testing mixtures of galectins and other types of compounds, for example a combination of galectins and TGF‐β1.
- MeSH
- Fibroblasts metabolism pathology MeSH
- Galectins biosynthesis MeSH
- Collagen biosynthesis MeSH
- Blood Proteins biosynthesis MeSH
- Humans MeSH
- Tensile Strength * MeSH
- Wounds and Injuries metabolism pathology MeSH
- Gene Expression Regulation * MeSH
- Dermis metabolism pathology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Galectin-3 (Gal-3) is a β-galactoside-binding protein that influences various cell functions, including cell adhesion. We focused on the role of Gal-3 as an extracellular ligand mediating cell-matrix adhesion. We used human adipose tissue-derived stem cells and human umbilical vein endothelial cells that are promising for vascular tissue engineering. We found that these cells naturally contained Gal-3 on their surface and inside the cells. Moreover, they were able to associate with exogenous Gal-3 added to the culture medium. This association was reduced with a β-galactoside LacdiNAc (GalNAcβ1,4GlcNAc), a selective ligand of Gal-3, which binds to the carbohydrate recognition domain (CRD) in the Gal-3 molecule. This ligand was also able to detach Gal-3 newly associated with cells but not Gal-3 naturally present on cells. In addition, Gal-3 preadsorbed on plastic surfaces acted as an adhesion ligand for both cell types, and the cell adhesion was resistant to blocking with LacdiNAc. This result suggests that the adhesion was mediated by a binding site different from the CRD. The blocking of integrin adhesion receptors on cells with specific antibodies revealed that the cell adhesion to the preadsorbed Gal-3 was mediated, at least partially, by β1 and αV integrins-namely α5β1, αVβ3, and αVβ1 integrins.
- MeSH
- Cell Adhesion * MeSH
- Human Umbilical Vein Endothelial Cells cytology physiology MeSH
- Galectins metabolism MeSH
- Integrins metabolism MeSH
- Blood Proteins metabolism MeSH
- Cells, Cultured MeSH
- Humans MeSH
- Mesenchymal Stem Cells cytology physiology MeSH
- Cell-Matrix Junctions metabolism MeSH
- Protein Binding MeSH
- Binding Sites MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Galectins are carbohydrate-binding lectins that modulate the proliferation, apoptosis, adhesion, or migration of cells by cross-linking glycans on cell membranes or extracellular matrix components. Galectin-4 (Gal-4) is a tandem-repeat-type galectin expressed mainly in the epithelial cells of the gastrointestinal tract. It consists of an N- and a C-terminal carbohydrate-binding domain (CRD), each with distinct binding affinities, interconnected with a peptide linker. Compared to other more abundant galectins, the knowledge of the pathophysiology of Gal-4 is sparse. Its altered expression in tumor tissue is associated with, for example, colon, colorectal, and liver cancers, and it increases in tumor progression, and metastasis. There is also very limited information on the preferences of Gal-4 for its carbohydrate ligands, particularly with respect to Gal-4 subunits. Similarly, there is virtually no information on the interaction of Gal-4 with multivalent ligands. This work shows the expression and purification of Gal-4 and its subunits and presents a structure-affinity relationship study with a library of oligosaccharide ligands. Furthermore, the influence of multivalency is demonstrated in the interaction with a model lactosyl-decorated synthetic glycoconjugate. The present data may be used in biomedical research for the design of efficient ligands of Gal-4 with diagnostic or therapeutic potential.
- MeSH
- Galectin 4 * MeSH
- Galectins chemistry MeSH
- Humans MeSH
- Ligands MeSH
- Neoplasms * MeSH
- Oligosaccharides chemistry MeSH
- Carbohydrates MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Galectins are proteins of the family of human lectins. By binding terminal galactose units of cell surface glycans, they moderate biological and pathological processes such as cell signaling, cell adhesion, apoptosis, fibrosis, carcinogenesis, and metabolic disorders. The binding of monovalent glycans to galectins is usually relatively weak. Therefore, the presentation of carbohydrate ligands on multivalent scaffolds can efficiently increase and/or discriminate the affinity of the glycoconjugate to different galectins. A library of glycoclusters and glycodendrimers with various structural presentations of the common functionalized N-acetyllactosamine ligand was prepared to evaluate how the mode of presentation affects the affinity and selectivity to the two most abundant galectins, galectin-1 (Gal-1) and galectin-3 (Gal-3). In addition, the effect of a one- to two-unit carbohydrate spacer on the affinity of the glycoconjugates was determined. A new design of the biolayer interferometry (BLI) method with specific AVI-tagged constructs was used to determine the affinity to galectins, and compared with the gold-standard method of isothermal titration calorimetry (ITC). This study reveals new routes to low nanomolar glycoconjugate inhibitors of galectins of interest for biomedical research.
- MeSH
- Galectins * metabolism MeSH
- Glycoconjugates * pharmacology chemistry MeSH
- Humans MeSH
- Ligands MeSH
- Polysaccharides metabolism MeSH
- Carbohydrates chemistry MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
The binding of human galectins by glycomimetic inhibitors is a promising therapeutic approach. The structurally distinct group of tandem-repeat galectins has scarcely been studied so far, and there is hardly any knowledge on their ligand specificity or their inhibitory potential, particularly concerning non-natural carbohydrates. Here, we present the synthesis of a library of seven 3-O-disubstituted thiodigalactoside-derived glycomimetics and their affinity to two tandem-repeat galectins, Gal-8 and Gal-9. The straightforward synthesis of these glycomimetics involved dibutyltin oxide-catalyzed 3,3́-O-disubstitution of commercially available unprotected thiodigalactoside, and conjugation of various aryl substituents by copper-catalyzed Huisgen azide-alkyne cycloaddition (CuAAC). The inhibitory potential of the prepared glycomimetics for Gal-8 and Gal-9 was assessed, and compared with the established galectins Gal-1 and Gal-3. The introduction of C-3 substituents resulted in an over 40-fold increase in affinity compared with unmodified TDG. The structure-affinity relations within the studied series were discussed using molecular modeling. Furthermore, the prepared glycomimetics were shown to scavenge Gal-8 and Gal-9 from the surface of cancer cells. This pioneering study on the synthetic inhibitors especially of Gal-9 identified lead compounds that may be used in further biomedical research.
- MeSH
- Galectins * metabolism MeSH
- Humans MeSH
- Carbohydrates chemistry MeSH
- Thiogalactosides * chemistry MeSH
- Protein Binding MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
