Hyaluronan, a linear glycosaminoglycan comprising D-N-acetylglucosamine and D-glucuronic acid, is the main component of the extracellular matrix. Its influence on cell proliferation, migration, inflammation, signalling, and other functions, depends heavily on its molecular weight and chemical modification. Unsaturated HA oligosaccharides are available in defined length and purity. Their potential therapeutic utility can be further improved by chemical modification, e. g., reduction. No synthesis of such modified oligosaccharides, either stepwise or by hyaluronan cleavage, has been reported yet. Here we show a three-step synthesis (esterification, depolymerization and reduction) of unsaturated even numbered hyaluronan oligosaccharides with carboxylates and the reducing terminus reduced to an alcohol. Particular oligosaccharides were synthesised. The modified oligosaccharides are not cleaved by mammalian or bacterial hyaluronidase and do not affect the growth of mouse and human fibroblasts. Further, MTT and NRU viability tests showed that they inhibit the growth of human colon carcinoma cells HT-29 by 20-50 % in concentrations 500-1000 μg/mL. Interestingly, this effect takes place regardless of CD44 receptor expression and was not observed with unmodified HA oligosaccharides. These compounds could serve as enzymatically stable building blocks for biologically active substances.
- MeSH
- antigeny CD44 metabolismus MeSH
- buňky HT-29 MeSH
- cytostatické látky * farmakologie chemie chemická syntéza MeSH
- fibroblasty účinky léků MeSH
- hyaluronoglukosaminidasa * metabolismus antagonisté a inhibitory MeSH
- kyselina hyaluronová * chemie farmakologie MeSH
- lidé MeSH
- myši MeSH
- oligosacharidy * chemie farmakologie MeSH
- proliferace buněk * účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Due to their large active surface, high loading efficiency, and tunable dissolution profiles, nanofibrous mats are often cited as promising drug carriers or antimicrobial membranes. Hyaluronic acid has outstanding biocompatibility, but it is hydrophilic. Nanofibrous structures made from hyaluronan dissolve immediately, making them unsuitable for controlled drug release and longer applications. We aimed to prepare a hyaluronan-based antimicrobial nanofibrous material, which would retain its integrity in aqueous environments. Self-supporting nanofibrous mats containing octenidine dihydrochloride or triclosan were produced by electrospinning from hydrophobized hyaluronan modified with a symmetric lauric acid anhydride. The nanofibrous mats required no cross-linking to be stable in PBS for 7 days. The encapsulation efficiency of antiseptics was nearly 100%. Minimal release of octenidine was observed, while up to 30% of triclosan was gradually released in 72 h. The nanofibrous materials exhibited antimicrobial activity, the fibroblast viability was directly dependent on the antiseptic content and its release.
- MeSH
- antibakteriální látky chemie farmakologie toxicita MeSH
- buňky 3T3 MeSH
- hydrofobní a hydrofilní interakce MeSH
- iminy chemie farmakologie toxicita MeSH
- kyselina hyaluronová chemie farmakologie toxicita MeSH
- léky s prodlouženým účinkem chemie farmakologie toxicita MeSH
- mikrobiální testy citlivosti MeSH
- myši MeSH
- nanovlákna chemie toxicita MeSH
- nosiče léků chemie farmakologie toxicita MeSH
- Pseudomonas aeruginosa účinky léků MeSH
- pyridiny chemie farmakologie toxicita MeSH
- Staphylococcus aureus účinky léků MeSH
- triclosan chemie farmakologie toxicita MeSH
- uvolňování léčiv MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Electron-deficient chlorine covalently immobilised on an amido group of hyaluronic acid (HA) can be potentially exceptional for applications requiring biodegradable and biocompatible polymers with enhanced antibacterial or antiviral activity. This expectation is supported by the assumption that a small amount of HA chloramide (HACl) is formed in the extracellular matrix under inflammatory conditions by a reaction of endogenous HA with hypochlorous acid (HClO) generated by a myeloperoxidase/H2O2/Cl- system. HACl synthesis optimisation showed significant limitations of HClO as an oxidative agent where only lower degrees of substitution (DS) was achieved. Commercially available oxidative agents based on chlorinated isocyanuric acid were successfully tested, producing the HA chain with almost entirely chlorinated amidic groups. The structure of the final HACl was thoroughly studied using advanced 2-dimensional NMR methodologies and LC/MS. Stability of HACl at different temperatures was monitored over 12 months. Preliminary antimicrobial and antiviral tests demonstrated the potential of HACl for applications in biomedicine.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- antifungální látky chemie farmakologie MeSH
- antivirové látky chemie farmakologie MeSH
- Bacteria účinky léků MeSH
- chloraminy chemie farmakologie MeSH
- halogenace MeSH
- houby účinky léků MeSH
- kyselina chlorná chemie MeSH
- kyselina hyaluronová chemie MeSH
- viry účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
This study aims to design an optimal polyelectrolyte multilayer film of poly-l-lysine (PLL) and hyaluronic acid (HA) as an anti-inflammatory cytokine release system in order to decrease the implant failure due to any immune reactions. The chemical modification of the HA with aldehyde moieties allows self-cross-linking of the film and an improvement in the mechanical properties of the film. The cross-linking of the film and the release of immunomodulatory cytokine (IL-4) stimulate the differentiation of primary human monocytes seeded on the films into pro-healing macrophages phenotype. This induces the production of anti-inflammatory cytokines (IL1-RA and CCL18) and the decrease of pro-inflammatory cytokines secreted (IL-12, TNF-α, and IL-1β). Moreover, we demonstrate that cross-linking PLL/HA film using HA-aldehyde is already effective by itself to limit inflammatory processes. Finally, this functionalized self-cross-linked PLL/HA-aldehyde films constitutes an innovative and efficient candidate for immunomodulation of any kind of implants of various architecture and properties.
- MeSH
- buněčná adheze účinky léků MeSH
- buněčná diferenciace účinky léků MeSH
- cytokiny aplikace a dávkování chemie MeSH
- imunomodulace účinky léků MeSH
- kultivované buňky MeSH
- kyselina hyaluronová chemie MeSH
- lidé MeSH
- makrofágy cytologie účinky léků metabolismus MeSH
- monocyty cytologie účinky léků metabolismus MeSH
- polyelektrolyty chemie MeSH
- povrchové vlastnosti MeSH
- reagencia zkříženě vázaná chemie MeSH
- zánět farmakoterapie imunologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Native hyaluronan (HA) has been oxidized to polyaldehyde polymers with a degree of substitution (DS) of up to 50%. Two different procedures enabling the control of the degree of substitution were followed in this study. Selective oxidation of primary hydroxyl groups of N-acetyl-D-glucosamine of hyaluronan was performed either in an aqueous solution containing AcNH-TEMPO/NaBr/NaOCl or in an aprotic solvent containing Dess-Martin periodinane (DMP). It was found that a change of reaction parameters (reaction time and temperature, type of catalyst, oxidant-to-HA ratio, presence of nitrogen, buffer type, and concentration) had an influence on the degree of substitution and molecular weight. The derivatives were characterized by MS, NMR spectroscopy, and SEC-MALLS. Degradation of hyaluronic acid by the oxidant was observed and confirmed by SEC. The effect of oxidized derivatives of hyaluronan on cells was studied by means of NIH 3T3 fibroblast viability, which indicates that prepared hyaluronan polyaldehydes are biocompatible and suitable for medical applications and tissue engineering. The function of polyaldehyde as precursor for other modification was illustrated in the reaction with lysine.
- MeSH
- acetylglukosamin chemie MeSH
- aldehydy chemická syntéza farmakologie MeSH
- biokompatibilní materiály chemická syntéza farmakologie MeSH
- biopolymery chemie farmakologie MeSH
- bromidy chemie MeSH
- buňky NIH 3T3 MeSH
- chlornan sodný chemie MeSH
- cyklické N-oxidy chemie MeSH
- dusík chemie MeSH
- iminopyranosy chemie MeSH
- katalýza MeSH
- kyselina hyaluronová analogy a deriváty chemická syntéza farmakologie MeSH
- magnetická rezonanční spektroskopie MeSH
- molekulová hmotnost MeSH
- myši MeSH
- oxidace-redukce MeSH
- sloučeniny sodíku chemie MeSH
- teplota MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Macromolecular conjugates of a natural polysaccharide, hyaluronic acid, with diethylenetriaminepentaacetic acid (DTPA)-metal complexes were synthesized and characterized by FTIR, NMR, SEC-MALLS and ICP analysis. Several parameters of the cross-linking reaction as molecular weight of starting HA, temperature, equivalent of DTPA bis-anhydride, concentration of HA, presence of transacylation catalyst DMAP and reaction time were studied. The mechanism for the reaction was suggested and relationship between the molecular weight assigned by SEC-MALLS, reaction parameters and rheological properties of the final cross-linked products were investigated.
Three different procedures for the labeling of hyaluronan (HA) with (111)In, (125)I and (14)C radionuclides were compared, and the kinetic stability of radiolabeled HA under different conditions (saline, artificial gastric juice and plasma) was established. Modification of HA structure with bifunctional chelating agents (DTPA) or with the prosthetic group (tyramine or tyrosine) was essential prior (111)In and (125)I labeling. These chemical labeling techniques were fast, simple and inexpensive, and labeled agents with a high specific activity were obtained. The only disadvantage of these methods was the occurrence of unknown functional groups in the HA molecule requiring further characterization of the compound. Conversely, HA labeling with (14)C by biotechnological synthesis was found to be rather expensive and time-consuming process. Although, the final product (14)C-HA was identical to natural HA its low specific activity presents certain limitation for its application in biological experiments. Stability studies showed that (14)C-HA and (125)I-Tm-HA were stable in all studied mediums. In the case of (125)I-Trs-HA, stability slightly decreased in rat plasma and in artificial gastric juice with increasing time. The least stable was (111)In-DTPA-HA, which degraded completely after 48h in artificial gastric juice. Kinetic stability studies may provide primary information concerning the properties of radiolabeled HA in vitro, which is essential for the use and explanation of its behavior in biological experiments.
- MeSH
- krysa rodu rattus MeSH
- kyselina hyaluronová chemická syntéza farmakokinetika MeSH
- potkani Wistar MeSH
- radioizotopy india chemie farmakokinetika MeSH
- radioizotopy jodu chemie farmakokinetika MeSH
- radioizotopy uhlíku chemie farmakokinetika MeSH
- stabilita léku MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH