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Nanoliposomes decorated on their surface with ligands for Ab-peptides, the key morphological features of Alzheimer's disease (AD), have been synthesized and characterized for their ability to target Abpeptide aggregates. A tricyclic benzopyrane-glycofused structure has been exploited as Ab-peptide ligand, which was linked to liposomes via a copper-free, chemoselective, biocompatible click chemistry reaction. The tricyclic-decorated liposomes presented a mean diameter in the nanomolar range (150 e200 nm), a negative z-potential and a good stability, at least up to one month. Integrity studies performed in the presence of serum proteins indicated that these decorated nanoliposomes fulfill the requirements for in vivo applications. NMR experiments carried out with Ab1-42 oligomers using both surface functionalized and plain (control) liposomes, revealed that the binding ability of the nanoliposomes was mediated by the presence of the tricyclic ligand on their surface. Finally ThT assay carried out with tricyclic-decorated liposomes showed significant decrease in thioflavine T fluorescence after 24 h, suggesting a significant inhibition/delay of Ab1-42 aggregation

A set of heterobifunctional oligo ethylene glycols have been synthesized in a straightforward and stepwise manner starting from inexpensive, commercially available, tetraethylene glycol. Introduction of terminal allyl moieties followed by reductive ozonolysis allowed controlled elongation. Mono-allyl derivatives were used for the elongation with a functionalized moiety and for successive introduction of different functional groups on the chain terminal

Cancer is one of the major causes of death worldwide. As a consequence, many different therapeutic approaches, including the use of glycosides as anticancer agents, have been developed. Various glycosylated natural products exhibit high activity against a variety of microbes and human tumors. In this review we classify glycosides according to the nature of their aglycone (non-saccharidic) part. Among them, we describe anthracyclines, aureolic acids, enediyne antibiotics, macrolide and glycopeptides presenting different strengths and mechanisms of action against human cancers. In some cases, the glycosidic residue is crucial for their activity, such as in anthracycline, aureolic acid and enediyne antibiotics; in other cases, Nature has exploited glycosylation to improve solubility or pharmacokinetic properties, as in the glycopeptides. In this review we focus our attention on natural glycoconjugates with anticancer properties. The structure of several of the carbohydrate moieties found in these conjugates and their role are described. The structure-activity relationship of some of these compounds, together with the structural features of their interaction with the biological targets, are also reported. Taken together, all this information is useful for the design of new potential anti-tumor drugs. © The Royal Society of Chemistry 2011.

A promising strategy to enhance blood-brain barrier penetration by drugs is the functionalization of nanocarriers with uptake-facilitating ligands. We studied the cellular uptake, by cultured RBE4 brain capillary endothelial cells, of nanoliposomes (NLs) covalently coupled with monomer or tandem dimer of apolipoprotein E (ApoE)-derived peptides (residues 141-150), at various densities. NLs without functionalization did not show either relevant membrane accumulation or cellular uptake, as monitored by confocal microscopy and quantified by fluorescence-activated cell sorting. Functionalization with peptides mediated an efficient NLs uptake that increased with peptide density; NLs carrying monomeric peptide performed the best. Moreover, we studied the ability of ApoE-NLs to enhance the transport of a drug payload through a RBE4 cell monolayer. The permeability of a tritiated curcumin derivative was enhanced after its entrapment into ApoE-NLs, in particular those functionalized with the dimer (+83% with respect to free drug, P < 0.01). Thus, these NLs appear particularly suitable for implementing further strategies for drug brain targeting. From the Clinical Editor: Re and her collaborators present a method for delivering nanoliposomes via the blood brain barrier by utilizing peptide fragments including monomers or tandem dimers ApoE. This method may enable enhanced nanoliposome associated drug delivery via the blood-brain barrier, which would have enormous significance in neurodegenerative and other CNS disorders

Several glycoprocessing enzymes and glycoreceptors have been recognized as important targets for therapeutic intervention. This concept inspired the development of important classes of therapeutic, such as anti flu drugs inhibiting influenza virus neuraminidase, anti-inflammatory drugs targeting lectin-sialyl-Lewis x interaction and glycosidase inhibitors against HIV, Gaucher’s disease, hepatitis, cancer. These therapeutics are mainly carbohydrate mimics in which proper modifications allow a stronger interaction with the target protein, an higher stability, better pharmacokinetic properties and eventually an easier synthesis. Furthermore, the conformational rigidity and polyfunctionality of carbohydrates, stimulate their use as scaffolds for the generation of libraries by combinatorial decoration with different pharmacophores. This review will present examples on how to exploit carbohydrates mimics and scaffolds in drug research.

Small molecules altering protein functions as inhibitors, agonists or antagonists, find application in systems biology enabling an analysis of the in vivo consequences of these alterations. In this context carbohydrates are ideal tools, not only because they are involved in a variety of recognition phenomena of biological relevance, but also because they are ideal scaffolds to generate libraries of bioactive compounds. Examples of design, synthesis and biological assays of different carbohydrate based inhibitors or protein ligands are reported. Exploiting NMR methods, the binding between a small molecules (inhibitor or ligand) and a proteins can be detected, the affinity measured, and the interaction topology defined. This set of information is useful not only to clarify the mechanism of protein-ligand interaction, but also to improve the design of new inhibitors/ligands. The multifunctionality and the conformational rigidity of carbohydrates make this class of compounds the ideal scaffolds to generate libraries exploiting the combinatorial approach. An example of solid phase combinatorial synthesis of a library of 37 compounds is reported

Our work shows how poly(ethylene glycol), differently functionalysed at two ends, can be easily and efficiently synthesised from commercial synthetic dihydroxy PEG 600. First, we linked the polymer onto functionalysed silica gel using one of its hydroxyl end. Then the second hydroxy group was modified, and finally, the desymmetrized PEG was cleaved from the solid support