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Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a polyphenol found in various plants, especially in the skin of red grapes. The effect of resveratrol on human health is the topic of numerous studies. In fact this molecule has shown anti-cancer, anti-inflammatory, blood-sugar-lowering ability and beneficial cardiovascular effects. However, for many polyphenol compounds of natural origin bioavailability is limited by low solubility in biological fluids, as well as by rapid metabolization in vivo. Therefore, appropriate carriers are required to obtain efficient therapeutics along with low administration doses.Liposomes are excellent candidates for drug delivery purposes, due to their biocompatibility, wide choice of physico-chemical properties and easy preparation.In this paper liposome formulations made by a saturated phosphatidyl-choline (DPPC) and cholesterol (or its positively charged derivative DC-CHOL) were chosen to optimize the loading of a rigid hydrophobic molecule such as resveratrol.Plain and resveratrol loaded liposomes were characterized for size, surface charge and structural details by complementary techniques, i.e. Dynamic Light Scattering (DLS), Zeta potential and Small Angle X-ray Scattering (SAXS). Nuclear and Electron Spin magnetic resonances (NMR and ESR, respectively) were also used to gain information at the molecular scale.The obtained results allowed to give an account of loaded liposomes in which resveratrol interacted with the bilayer, being more deeply inserted in cationic liposomes than in zwitterionic liposomes. Relevant properties such as the mean size and the presence of oligolamellar structures were influenced by the loading of RESV guest molecules.The toxicity of all these systems was tested on stabilized cell lines (mouse fibroblast NIH-3T3 and human astrocytes U373-MG), showing that cell viability was not affected by the administration of liposomial resveratrol.

To favor bone reconstitution with biomaterials endothelial cells should maintain proper functions to drive angiogenesis. To this aim nanocrystals of hydroxyapatite (HA) have been synthesized and characterized on endothelial cells. Microvascular endothelial cells have been exposed to stoichiometric HA nanocrystals. Cell morphology and organization of cytoskeletal proteins have been monitored by SEM analysis and immunofluorescence. Biochemical markers of physiological and pathological responses of endothelial cells, endothelial constitutive nitric oxide synthase, and cycloxygenase-2 (ecNOS and COX-2, respectively) have been measured by immunofluorescence. Crystallized HA sustained endothelial survival without any cytotoxic effect. At the observation with SEM, endothelial cell morphology was maintained in the presence of HA. The localization and organization of beta-actin documented the formation of stress fibers, indicating an activation of endothelial cells induced by HA nanocrystals. Immunohistochemistry for biochemical key signaling pathways in endothelium demonstrated that nanocrystals of HA maintained the expression of ecNOS and did not increase COX-2 expression. In conclusion, the present findings indicate that HA nanocrystals exhibit high biocompatibility for microvascular endothelium. In the presence of HA nanocrystals endothelial cells maintain biochemical markers of healthy endothelium. They do not acquire a proinflammatory or thrombogenic phenotype, but express markers of functioning endothelium that might contribute to angiogenesis.

We report the discovery of compound 4a, a potent β-lactam-based monoacylglycerol lipase (MGL) inhibitor characterized by an irreversible and stereoselective mechanism of action, high membrane permeability, high brain penetration evaluated using a human in vitro blood-brain barrier model, high selectivity in binding and affinity-based proteomic profiling assays, and low in vitro toxicity. Mode-of-action studies demonstrate that 4a, by blocking MGL, increases 2-arachidonoylglycerol and behaves as a cannabinoid (CB1/CB2) receptor indirect agonist. Administration of 4a in mice suffering from experimental autoimmune encephalitis ameliorates the severity of the clinical symptoms in a CB1/CB2-dependent manner. Moreover, 4a produced analgesic effects in a rodent model of acute inflammatory pain, which was antagonized by CB1 and CB2 receptor antagonists/inverse agonists. 4a also relieves the neuropathic hypersensitivity induced by oxaliplatin. Given these evidence, 4a, as MGL selective inhibitor, could represent a valuable lead for the future development of therapeutic options for multiple sclerosis and chronic pain

PVA based hydrogels were synthesised using, as crosslinking agent, trisodium trimetaphosphate (STMP) to obtain potential substitutes for the vitreous body of the eye. The hydrogels, obtained using different amounts of STMP, were characterised by Infrared Spectroscopy which confirmed the successful occurrence of crosslinking reaction. The mechanical spectra of the fully hydrated samples confirmed covalently crosslinked systems (i.e. G' > G''). The rheological analysis pointed out that only one of the hydrogels (PVA STMP 8:1) showed a behaviour similar to that of human vitreous. The hydrogel was also subjected to injection through a small needle, a procedure that is essential in the use of vitreous substitutes. Further analysis in terms of light transmittance, water content measurements, diffusion coefficient and cytotoxicity confirmed the applicability of such a hydrogel as vitreous substitute.

Anticoagulant polymer sulfated hyaluronic acid was patterned immobilized on a poly(ethylene terephthalate) (PET) film in a specific pattern by photolithography. Hyaluronic acid was sulfated by a sulfur trioxide-pyridine complex. The polymer was coupled with azidoaniline. The derivatized polymer was cast on a PET film from aqueous solution. After drying, the film was photoirradiated in the presence or absence of a photomask. The micropatterning was confirmed by staining with a dye, brilliant green. Since the anticoagulant polymer has negative charges, the cationic dye was adsorbed on the regions where the anticoagulant polymer was immobilized. Platelet adhesion was reduced on the sulfated hyaluronic acid-immobilized areas. The immobilized sulfated hyaluronic acid significantly reduced thrombus formation.

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