Trehalose-Based Nucleolipids as Nanocarriers for Autophagy Modulation: An In Vitro Study.

The Autophagy Lysosomal Pathway is one of the most important mechanisms for removing dysfunctional cellular components. Increasing evidence suggests that alterations in this pathway play a pathogenic role in Parkinson's disease, making it a point of particular vulnerability. Numerous studies have proposed nanotechnologies as a promising approach for delivering active substances within the central nervous system to treat and diagnose neurodegenerative diseases. In this context, the aim was to propose the development of a new pharmaceutical technology for the treatment of neurodegenerative diseases. We designed a trehalose-based nanosystem by combining both a small natural autophagy enhancer molecule named trehalose and an amphiphilic nucleolipid conjugate. To improve nucleolipid protection and cellular uptake, these conjugates were formulated by rapid mixing in either solid lipid nanoparticles (Ø = 120.4 ± 1.4 nm) or incorporated into poly(lactic-co-glycolic acid) nanoparticles (Ø = 167.2 ± 2.4 nm). In vitro biological assays demonstrated a safe and an efficient cellular uptake associated with autophagy induction. Overall, these nucleolipid-based formulations represent a promising new pharmaceutical tool to deliver trehalose and restore the autophagy impaired function.

PLGA-Based Nanoparticles for Neuroprotective Drug Delivery in Neurodegenerative Diseases.

Treatment of neurodegenerative diseases has become one of the most challenging topics of the last decades due to their prevalence and increasing societal cost. The crucial point of the non-invasive therapeutic strategy for neurological disorder treatment relies on the drugs' passage through the blood-brain barrier (BBB). Indeed, this biological barrier is involved in cerebral vascular homeostasis by its tight junctions, for example. One way to overcome this limit and deliver neuroprotective substances in the brain relies on nanotechnology-based approaches. Poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) are biocompatible, non-toxic, and provide many benefits, including improved drug solubility, protection against enzymatic digestion, increased targeting efficiency, and enhanced cellular internalization. This review will present an overview of the latest findings and advances in the PLGA NP-based approach for neuroprotective drug delivery in the case of neurodegenerative disease treatment (i.e., Alzheimer's, Parkinson's, Huntington's diseases, Amyotrophic Lateral, and Multiple Sclerosis).

Bolaamphiphile-based supramolecular gels with drugs eliciting membrane effects.

Supramolecular chemistry has garnered important interest in recent years toward improving therapeutic efficacy via drug delivery approaches. Although self-assemblies have been deeply investigated, the design of novel drugs leveraging supramolecular chemistry is less known. In this contribution, we show that a Low Molecular Weight Gel (LMWG) can elicit cancer cell apoptosis. This biological effect results from the unique supramolecular properties of a bolaamphiphile-based gelator, which allow for strong interaction with the lipid membrane. This novel supramolecular-drug paradigm opens up new possibilities for therapeutic applications targeting membrane lipids.

Correction: Supramolecular gels derived from nucleoside based bolaamphiphiles as a light-sensitive soft material.

Correction for 'Supramolecular gels derived from nucleoside based bolaamphiphiles as a light-sensitive soft material' by Julie Baillet et al., Chem. Commun., 2020, 56, 3397-3400, DOI: 10.1039/D0CC00336K.

ß-Galactosidase instructed self-assembly of supramolecular bolaamphiphiles hydrogelators.

ß-Galactosidase instructed supramolecular assemblies of Low Molecular Weight Gelators (LMWGs) derived from glyconucleo-bolaamphiphiles have been designed. These precursors, comprising galactose sensitive units at both polar heads, showed the formation of hydrogels upon the action of ß-galactosidase.

Supramolecular gels derived from nucleoside based bolaamphiphiles as a light-sensitive soft material.

Light-sensitive Low Molecular Weight Gelators (LMWGs) derived from glyconucleoside bolaamphiphiles containing a stilbene unit displayed gelation abilities in hydroalcoholic mixtures. These materials showed a gel-sol transition under UV irradiation thanks to E-Z isomerization of stilbene and could find potential applications as drug delivery systems.

Lipid and Nucleic Acid Chemistries: Combining the Best of Both Worlds to Construct Advanced Biomaterials.

Hybrid synthetic amphiphilic biomolecules are emerging as promising supramolecular materials for biomedical and technological applications. Herein, recent progress in the field of nucleic acid based lipids is highlighted with an emphasis on their molecular design, synthesis, supramolecular properties, physicochemical behaviors, and applications in the field of health science and technology. In the first section, the design and the study of nucleolipids are in focus and then the glyconucleolipid family is discussed. In the last section, recent contributions of responsive materials involving nucleolipids and their use as smart drug delivery systems are discussed. The supramolecular materials generated by nucleic acid based lipids open new challenges for biomedical applications, including the fields of medicinal chemistry, biosensors, biomaterials for tissue engineering, drug delivery, and the decontamination of nanoparticles.

Recent Advances in the Chemistry of Glycoconjugate Amphiphiles.

Glyconanoparticles essentially result from the (covalent or noncovalent) association of nanometer-scale objects with carbohydrates. Such glyconanoparticles can take many different forms and this mini review will focus only on soft materials (colloids, liposomes, gels etc.) with a special emphasis on glycolipid-derived nanomaterials and the chemistry involved for their synthesis. Also this contribution presents Low Molecular Weight Gels (LMWGs) stabilized by glycoconjugate amphiphiles. Such soft materials are likely to be of interest for different biomedical applications.

Low molecular weight hydrogels derived from urea based-bolaamphiphiles as new injectable biomaterials.

There is a critical need for soft materials in the field of regenerative medicine and tissue engineering. However, designing injectable hydrogel scaffolds encompassing both adequate mechanical and biological properties remains a key challenge for in vivo applications. Here we use a bottom-up approach for synthesizing supramolecular gels to generate novel biomaterial candidates. We evaluated the low molecular weight gels candidates in vivo and identified one urea-containing molecule, compound 16, that avoid foreign body reactions in mice. The self-assembly of bolaamphiphiles creates a unique hydrogel supramolecular structures featuring fast gelation kinetics, high elastic moduli, thixotropic, and thermal reversibility properties. This soft material, which inhibits recognition by macrophages and fibrous deposition, exhibits long-term stability after in vivo injection.

Carbamate-Based Bolaamphiphile as Low-Molecular-Weight Hydrogelators.

A new bolaamphiphile analog featuring carbamate moieties was synthesized in six steps starting from thymidine. The amphiphile structure exhibits nucleoside-sugar polar heads attached to a hydrophobic spacer via carbamate (urethane) functions. This molecular structure, which possesses additional H-bonding capabilities, induces the stabilization of low-molecular-weight gels (LMWGs) in water. The rheological studies revealed that the new bolaamphiphile 7 stabilizes thixotropic hydrogels with a high elastic modulus (G' > 50 kPa).

Control of stem-cell behavior by fine tuning the supramolecular assemblies of low-molecular-weight gelators.

Controlling the behavior of stem cells through the supramolecular architecture of the extracellular matrix remains an important challenge in the culture of stem cells. Herein, we report on a new generation of low-molecular-weight gelators (LMWG) for the culture of isolated stem cells. The bola-amphiphile structures derived from nucleolipids feature unique rheological and biological properties suitable for tissue engineering applications. The bola-amphiphile-based hydrogel scaffold exhibits the following essential properties: it is nontoxic, easy to handle, injectable, and features a biocompatible rheology. The reported glycosyl-nucleoside bola-amphiphiles (GNBA) are the first examples of LMWG that allow the culture of isolated stem cells in a gel matrix. The results (TEM observations and rheology) suggest that the supramolecular organizations of the matrix play a role in the behavior of stem cells in 3D environments.

Glycosyl-Nucleolipids as new bioinspired amphiphiles.

Four new Glycosyl-NucleoLipid (GNL) analogs featuring either a single fluorocarbon or double hydrocarbon chains were synthesized in good yields from azido thymidine as starting material. Physicochemical studies (surface tension measurements, differential scanning calorimetry) indicate that hydroxybutanamide-based GNLs feature endothermic phase transition temperatures like the previously reported double chain glycerol-based GNLs. The second generation of GNFs featuring a free nucleobase reported here presents a better surface activity (lower glim) compared to the first generation of GNFs.

A thermosensitive low molecular weight hydrogel as scaffold for tissue engineering.

Hydrogels that are non-toxic, easy to use, cytocompatible, injectable and degradable are valuable biomaterials for tissue engineering and tissue repair. However, few compounds currently fulfil these requirements. In this study, we describe the biological properties of a new type of thermosensitive hydrogel based on low-molecular weight glycosyl-nucleosyl-fluorinated (GNF) compound. This gel forms within 25 min by self-assembly of monomers as temperature decreases. It degrades slowly in vitro and in vivo. It induces moderate chronic inflammation and is progressively invaded by host cells and vessels, suggesting good integration to the host environment. Although human adult mesenchymal stem cells derived from adipose tissue (ASC) cannot adhere on the gel surface or within a 3D gel scaffold, cell aggregates grow and differentiate normally when entrapped in the GNF-based gel. Moreover, this hydrogel stimulates osteoblast differentiation of ASC in the absence of osteogenic factors. When implanted in mice, gel-entrapped cell aggregates survive for several weeks in contrast with gel-free spheroids. They are maintained in their original site of implantation where they interact with the host tissue and adhere on the extracellular matrix. They can differentiate in situ into alkaline phosphatase positive osteoblasts, which deposit a calcium phosphate-rich matrix. When injected into subcutaneous sites, gel-encapsulated cells show similar biological properties as implanted gel-cells complexes. These data point GNF-based gels as a novel class of hydrogels with original properties, in particular osteogenic potential, susceptible of providing new therapeutic solutions especially for bone tissue engineering applications.

Glycosylated nucleoside lipid promotes the liposome internalization in stem cells.

We report new glycosyl-nucleoside-lipid based liposomes decorated with sugar moieties. The GNL-liposomes feature a suitable glycosylated surface for their internalization into ADSC stem cells.

Antiproliferative effect on HepaRG cell cultures of new calix[4]arenes. Part II.

Cell cycle progression is dependent on the intracellular iron level and chelators can lead to iron depletion and decrease cell proliferation. This antiproliferative effect can be inhibited by exogenous iron. In this work, we present the synthesis of some new synthetic calix[4]arene podands bearing diamino-tetraesters, diamino-tetraalcohols, diamino-tetraacid and tetraaryloxypentoxy groups at the lower rim, designed as potential iron chelators. We report their effect on cell proliferation, in comparison with the new oral chelator ICL670A (4-[3,5-bis-(2-hydroxyphenyl)-1,2,4-triazol-1-yl]-benzoic acid). The antiproliferative effect of these new compounds was studied in the human hepatocarcinoma HepaRG cell cultures using cell nuclei counting after staining with the DNA intercalating fluorescence dye, Hoechst 33342. Their cytotoxicity was evaluated by the extracellular LDH activity. Preliminary results indicated that their antiproliferative effect was mainly due to their cytotoxicity. The efficiency of these compounds, being comparable to that of ICL670, was independent of iron depletion. This effect remains to be further explored. Moreover, it also shows that the new substituted calix[4]arenes could open the way to valuable new approaches for medicinal chemistry scaffolding.

Synthesis and in vitro cytostatic activity of new beta-D-arabino furan[1',2':4,5]oxazolo- and arabino-pyrimidinone derivatives.

A series of nucleoside derivatives was obtained via heteroatom annulation of the amino oxazoline of D-(-)-arabinose. Unequivocal proofs for the stereostructure of some new arabinosyl pyrimidinone derivatives were obtained by X-ray structure analysis. These newly synthesized compounds were then evaluated for their cytostatic activity against murine leukemia (L1210), and human T-lymphocytes (Molt 4/C8 and CEM). Of all the compounds in the series, the protected silylated tricyclic fused pyrimidinone 10 showed the most significant antitumor activity against murine leukemia L1210 (IC(50)=6 microM), and human T-lymphocytes cells Molt 4/C8 (IC(50)=7.9 microM) and CEM/0 cell lines (IC(50)=7.5 microM). None of the compounds exhibited significant antiviral inhibitory activities.

Synthesis of N epsilon-(7-diethylaminocoumarin-3-carboxyl)- and N epsilon-(7-methoxycoumarin-3-carboxyl)-L-Fmoc lysine as tools for protease cleavage detection by fluorescence.

Two coumarin-labelled lysines were conveniently prepared as a fluorescence resonance energy transfer (FRET) pair for peptide cleavage detection. 7-Methoxy and 7-diethylamino coumarin-3-carboxylic acids were synthesized according to a modification of known procedures. Labelling at lysine was achieved in solution via the active N-hydroxysuccinimide ester of the carboxylic acid coumarin derivatives to give the target compounds in good yield. Subsequently, these modified amino acids were used in solid phase peptide synthesis (SPPS), and their potential utility in an extracellular matrix metalloprotease (MMP-1) activity measurement via FRET and/or quenching studies was demonstrated.

Synthesis of novel fluorogenic L-Fmoc lysine derivatives as potential tools for imaging cells.

Two coumarin-labeled lysines were conveniently prepared as fluorescent probes. 7-Methoxy and 7-diethylamino coumarin-3-carboxylic acids were synthesized according to a modification of known procedures. Labeling at lysine was achieved in solution via the active N-hydroxysuccinimide ester of the carboxylic acid coumarin derivatives to give the target compounds in good yield. Spectroscopic data (UV-vis and fluorescence) were recorded for all compounds.

Synthesis and evaluation of organosilicon inhibitors of active purine transport in human osteoblasts.

In the search for new compounds that might, once incorporated into biomaterials, stimulate the natural processes of bone regeneration, a new series of silicon-containing alkyl nucleobase analogues has been synthesized. An active hypoxanthine transport process in human osteoblasts was demonstrated, with an apparent Michaelis constant of 2.3 microM and a maximum possible rate of 0.47 pmol s(-1) x 10(6) cell. The synthesized analogues were tested for toxicity in human osteoblasts. Nontoxic analogues were tested in competition transport studies with [(14)C]hypoxanthine. Two of them were found to inhibit the active transport of hypoxanthine in human osteoblasts, with IC(50) values of 6.5 and 11.6 microM.