RESUMEN
Natural glycoconjugates that form glycocalyx play important roles in various biological processes based on cell surface recognition through pattern recognition mechanisms. This work represents a new synthesis-based screening strategy to efficiently target the cancer cells by higher-order glycan pattern recognition in both cells and intact animals (mice). The use of the very fast, selective, and effective RIKEN click reaction (6π-azaelectrocyclization of unsaturated imines) allows to synthesize and screen various structurally well-defined glycoalbumins containing two and eventually four different N-glycan structures in a very short time. The importance of glycan pattern recognition is exemplified in both cell- and mouse-based experiments. The use of pattern recognition mechanisms for cell targeting represents a novel and promising strategy for the development of diagnostic, prophylactic, and therapeutic agents for various diseases including cancers.
Asunto(s)
Neoplasias , Polisacáridos , Animales , Productos Finales de Glicación Avanzada , Glicoconjugados , Ratones , Albúmina Sérica , Albúmina Sérica GlicadaRESUMEN
Metal complex catalysis within biological systems is largely limited to cell and bacterial systems. In this work, a glycoalbumin-AuIII complex was designed and developed that enables organ-specific, localized propargyl ester amidation with nearby proteins within live mice. The targeted reactivity can be imaged through the use of Cy7.5- and TAMRA-linked propargyl ester based fluorescent probes. This targeting system could enable the exploitation of other metal catalysis strategies for biomedical and clinical applications.
Asunto(s)
Complejos de Coordinación/química , Colorantes Fluorescentes/química , Oro/química , Albúmina Sérica/química , Animales , Catálisis , Complejos de Coordinación/farmacocinética , Colorantes Fluorescentes/farmacocinética , Productos Finales de Glicación Avanzada , Oro/farmacocinética , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Imagen Óptica/métodos , Albúmina Sérica/farmacocinética , Distribución Tisular , Albúmina Sérica GlicadaRESUMEN
This work represents the first broad study of testing diverse heterogenous glycoconjugates (7 different glycoalbumins) for their differential in vivo binding (11 different cancer cell types) in both cell- and animal-based studies. As a result, various changes in biodistribution, excretion, and even tumor adhesion were observed.
Asunto(s)
Moléculas de Adhesión Celular/farmacocinética , Glicoconjugados/farmacocinética , Albúmina Sérica/farmacocinética , Animales , Moléculas de Adhesión Celular/química , Línea Celular Tumoral , Productos Finales de Glicación Avanzada , Glicoconjugados/química , Humanos , Ratones , Especificidad de Órganos , Albúmina Sérica/química , Distribución Tisular , Albúmina Sérica GlicadaRESUMEN
Structurally well-defined heterogeneous N-glycoclusters are prepared on albumin via a double click procedure. The number of glycan molecules present, in addition to the spatial arrangement of glycans in the heterogeneous glycoclusters, plays an important role in the in vivo kinetics and organ-selective accumulation through glycan pattern recognition mechanisms.
RESUMEN
The gram-positive opportunistic bacterium Staphylococcus aureus is one of the most common causatives of a variety of diseases including skin and skin structure infection or nosocomial catheter-associated infections. The biofilm formation that is an important virulence factor of this microorganism renders the antibiotic therapy ineffective, because biofilm-embedded bacteria exhibit strongly increased tolerance to antimicrobials. Here, we describe a novel 3-chloro-5(S)-[(1R,2S,5R)-2-isopropyl-5-methylcyclohexyloxy]-4-[4-methylphenylsulfonyl]-2(5H)-furanone (F105), possessing a sulfonyl group and l-menthol moiety. Minimal inhibitory and bactericidal concentration values (MIC and MBC) of F105 were 10 and 40 mg/L, respectively, suggesting F105 biocidal properties. F105 exhibits pronounced activity against biofilm-embedded S. aureus and increases the efficacy of aminoglycosides (amikacin, gentamicin, and kanamycin) and benzalkonium chloride with fractional inhibitory concentration index values of 0.33-0.44 and 0.29, respectively, suggesting an alternative external treatment option, e.g., for wound infections. Moreover, low concentrations (0.5-1.3 mg/L) of F105 reduced the MICs of these antimicrobials twofold. By using confocal laser scanning microscopy and CFU counting, we show explicitly that F105 also restores the antimicrobial activity of gentamicin and ampicillin against S. aureus biofilms by several orders of magnitude. Biofilm structures were not destroyed but sterilized, with embedded cells being almost completely killed at twofold MBC. While F105 is quite toxic (CC50/MBC ratio 0.2), our data suggest that the F105 chemotype might be a promising starting point for the development of complex topical agents for combined anti-staphylococcal biofilm-therapies restoring the efficacy of some antibiotics against difficult to treat S. aureus biofilm.