Nanotechnological Approach to Increase the Antioxidant and Cytotoxic Efficacy of Crocin and Crocetin.

Crocin and crocetin are two interesting constituents of saffron (Crocus sativus) that possess important biological activities. Their use as therapeutic agents is strongly compromised by a scarce stability, poor absorption, and low bioavailability. Therefore, to improve these unfavorable features, the aim of the present work has been to apply a nanotechnological approach based on the formulation of solid lipid nanoparticles containing crocin and crocetin. Solid lipid nanoparticles were formulated according to crocin and crocetin chemical properties, using a variation of the quasi-emulsion solvent diffusion method to formulate crocin-solid lipid nanoparticles, while crocetin-solid lipid nanoparticles were prepared following the solvent diffusion method. Morphology and dimensional distribution of solid lipid nanoparticles have been characterized by differential scanning calorimetry and photon correlation spectroscopy, respectively, while the effect of drug incorporation versus time has been studied by Turbiscan technology. In order to verify the role of the nanotechnological approach on the biological activities of crocin and crocetin, the antioxidant and antiproliferative effects of these carotenoids once incorporated in lipid nanoparticles have been evaluated. For this aim, the oxygen radical absorbance capacity assay and the MTT test were used, respectively.The results pointed out the formulation of nanometric dispersions endowed with high homogeneity and stability, with an encapsulation efficiency ranging from 80 (crocetin-solid lipid nanoparticles) to 94% (crocin-crocetin). The oxygen radical absorbance capacity assay evidenced an interesting and prolonged antioxidant activity of crocin and crocetin once encapsulated in solid lipid nanoparticles, while the nanoencapsulation strategy showed a different mechanism in ameliorating the cytotoxic effect of these two substances.

An Alginate/Cyclodextrin Spray Drying Matrix to Improve Shelf Life and Antioxidant Efficiency of a Blood Orange By-Product Extract Rich in Polyphenols: MMPs Inhibition and Antiglycation Activity in Dysmetabolic Diseases.

Alginate and ß-cyclodextrin were used to produce easily dosable and spray-dried microsystems of a dried blood orange extract with antidysmetabolic properties, obtained from a by-product fluid extract. The spray-dried applied conditions were able to obtain a concentrate dried extract without the loss of AOA and with TPC and TMA values of 35-40% higher than that of the starting material. They were also effective in producing microparticles with 80-100% of encapsulation efficiency. The 2% sodium alginate was capable of improving the extract shelf life, while the beta-cyclodextrin (1 : 1 molar ratio with dried extract) prolonged the extract antioxidant efficiency by 6 hours. The good inhibition effect of the dried extract on the AGE formation and the MMP-2 and MMP-9 activity is presumably due to a synergic effect exerted by both anthocyanin and bioflavonoid extract compounds and was improved by the use of alginate and cyclodextrin.

Development and In Vitro Evaluation of an Innovative "Dietary Flavonoid Supplement" on Osteoarthritis Process.

The aim of this study was to evaluate the antidegenerative effect in osteoarthritis damage of eriocitrin alone and eriocitrin formulated as innovative "dietary flavonoid supplement." A complexation between eriocitrin and hydroxypropyl ß-cyclodextrin by solubilization/freeze-drying method was performed. The complex in solution was evaluated by phase solubility studies and the optimal 1 : 2 flavanone/cyclodextrin molar ratio was selected. Hydroxypropyl ß-cyclodextrin was able to complex eriocitrin as confirmed by UV-Vis absorption, DSC, and FTIR studies. The complex formed increased the eriocitrin water solubility (from 4.1 ± 0.2 g·L-1 to 11.0 ± 0.1 g·L-1) and dissolution rate (from 37.0% to 100%) in 30 min. The in vitro studies exhibit the notion that eriocitrin and its complex inhibit AGEs in a similar manner because hydroxypropyl ß-cyclodextrin does not interfere with the flavanone intrinsic property. Instead, the presence of cyclodextrin improves eriocitrin antioxidant stability maintaining a high fluorescence value until 8 hours with respect to the pure materials. Moreover, hydroxypropyl ß-cyclodextrin showed moderate GAGs restoration acting synergistically with the complexed compound to maintain the structural chondrocytes integrity. The results point out that ERT/HP-betaCD complex possesses technological and biological characteristics able to obtain an easily soluble nutraceutical product, which reduces the degenerative and oxidative damage which occurs in osteoarthritis, and improve the patient compliance.

Nanostructured Lipid Carriers (NLC) as Vehicles for Topical Administration of Sesamol: In Vitro Percutaneous Absorption Study and Evaluation of Antioxidant Activity.

Sesamol is a natural phenolic compound extracted from Sesamum indicum seed oil. Sesamol is endowed with several beneficial effects, but its use as a topical agent is strongly compromised by unfavorable chemical-physical properties. Therefore, to improve its characteristics, the aim of the present work was the formulation of nanostructured lipid carriers as drug delivery systems for topical administration of sesamol.Two different nanostructured lipid carrier systems have been produced based on the same solid lipid (Compritol® 888 ATO) but in a mixture with two different kinds of oil phase such as Miglyol® 812 (nanostructured lipid carrier-M) and sesame oil (nanostructured lipid carrier-PLUS). Morphology and dimensional distribution of nanostructured lipid carriers have been characterized by differential scanning calorimetry and photon correlation spectroscopy, respectively. The release pattern of sesamol from nanostructured lipid carriers was evaluated in vitro determining drug percutaneous absorption through excised human skin. Furthermore, an oxygen radical absorbance capacity assay was used to determine their antioxidant activity.From the results obtained, the method used to formulate nanostructured lipid carriers led to a homogeneous dispersion of particles in a nanometric range. Sesamol has been encapsulated efficiently in both nanostructured lipid carriers, with higher encapsulation efficiency values (> 90 %) when sesame oil was used as the oil phase (nanostructured lipid carrier-PLUS). In vitro evidences show that nanostructured lipid carrier dispersions were able to control the rate of sesamol diffusion through the skin, with respect to the reference formulations.Furthermore, the oxygen radical absorbance capacity assay pointed out an interesting and prolonged antioxidant activity of sesamol, especially when vehiculated by nanostructured lipid carrier-PLUS.

COPD: adherence to therapy.

Adherence to medical therapies is a growing issue, so much so that the World Health Organization defined it as "a new pharmacological problem". The main factors affecting compliance are: frequency of administration, rapid onset of action, role of device. The most severe consequence of non-adherence is the increased risk of poor clinical outcome, associated with worsening of the quality of life and increase in health-care expenditure. It appears crucial to identify those COPD patients who are "poorly or not at all compliant with their treatment". In order to evaluate adherence to the medical therapy, several methods were proposed, the most effective of which turned out to be self-reports, i.e. simple, brief questionnaires (e.g. Morisky test). To increase the likelihood of quickly identifying non-compliant patients, it may be useful to administer a simple questionnaire to naïve subjects (for example, in the waiting room before an examination) including six specific items allowing to identify the patient's key characteristics. Depending on the answers, patients who do not comply with their pharmacological treatment may be classified as belonging to 6 phenotypes. For patients who are already under treatment it might be useful to administer another short questionnaire during follow up examination. Once the risk of non-compliance is identified, four possible types of measures can be taken: prescription-related, educational, behavioral and complex combined measures (combination of two or more actions). Therefore, while it is clear that adherence in COPD is a critical issue, it is also obvious that raising awareness on the disease and improving cooperation among specialists, general practitioners, health-care professionals, and patients is the starting point at which this evolution should immediately begin. Each medication is able to foster good compliance with the therapy, and consequently to maximize the efficacy, by virtue of its specific inhaler and its own active ingredient.

Idebenone-loaded solid lipid nanoparticles for drug delivery to the skin: in vitro evaluation.

Idebenone (IDE), a synthetic derivative of ubiquinone, shows a potent antioxidant activity that could be beneficial in the treatment of skin oxidative damages. In this work, the feasibility of targeting IDE into the upper layers of the skin by topical application of IDE-loaded solid lipid nanoparticles (SLN) was evaluated. SLN loading different amounts of IDE were prepared by the phase inversion temperature method using cetyl palmitate as solid lipid and three different non-ionic surfactants: ceteth-20, isoceteth-20 and oleth-20. All IDE loaded SLN showed a mean particle size in the range of 30-49 nm and a single peak in size distribution. In vitro permeation/penetration experiments were performed on pig skin using Franz-type diffusion cells. IDE penetration into the different skin layers depended on the type of SLN used while no IDE permeation occurred from all the SLN under investigation. The highest IDE content was found in the epidermis when SLN contained ceteth-20 or isoceteth-20 as surfactant while IDE distribution into the upper skin layers depended on the amount of IDE loaded when oleth-20 was used as surfactant. These results suggest that the SLN tested could be an interesting carrier for IDE targeting to the upper skin layers.

Amphiphilic erythromycin-lipoamino acid ion pairs: characterization and in vitro microbiological evaluation.

A series of amphiphilic ion pairs of erythromycin (ERY) with lipoamino acids (LAAs) were produced. The ion pairs were prepared by evaporation of a water/ethanol co-solution of the drug and LAA bearing an alkyl side chain of 10-16 carbon atoms. For the sake of comparison, equimolar physical mixtures were prepared by triturating ERY and the LAA in the absence of any solvent. FTIR spectroscopy confirmed the structure of ion pairs, while differential scanning calorimetry and powder X-ray diffractometry were used to assess the formation of new saline species. The solubility pattern of the coevaporates in different aqueous and organic solvents confirmed their amphiphilic properties. ERY-LAA ion pairs were submitted to an in vitro microbiological assay against different bacterial strains, both susceptible and resistant to macrolides. The presence of the LAA moiety was shown not altering the antibacterial spectrum of activity of the drug. These results can be the basis for a further evaluation of ERY-LAA ion pairs as a mean to improve the penetration of the drug inside bacterial cells and to optimize the loading of ERY in lipid-based nanocarriers.

Enhancement of drug affinity for cell membranes by conjugation with lipoamino acids. I. Synthesis and biological evaluation of lipophilic conjugates of tranylcypromine.

Conjugation with lipoamino acids (LAAs) increases the lipophilicity of drug molecules. Because of their amphipatic nature, they also provide the conjugated drugs a 'membrane-like character', capable to facilitate their interaction with and penetration through cell membranes and biological barriers. To study such a feature, our aim is to collect experimental and computational data using a novel series of lipophilic conjugates between a model drug (tranylcypromine (TCP)) and LAA residues containing a short, a medium or a long alkyl side chain (C-4 to C-16), to provide a wide range of lipophilicity. For comparison, a corresponding set of amides of TCP with alkanoic or fatty acids was prepared and characterized. Their in vitro monoamine oxidase inhibitory activity also tested.

Characterization of the mechanism of interaction in ibuprofen-Eudragit RL100 coevaporates.

The present study is a preliminary exploration of the affinity between a carboxylic model drug, the nonsteroidal antiinflammatory agent ibuprofen (IBU) and Eudragit RL100 (RL) polymer. Due to the presence of a variable amount of quaternary ammonium groups in this matrix, physical and chemical interaction with the carboxylic drug can occur, which reinforces its scant mechanical dispersion in the polymer network and can ultimately affect its release profile in vitro and in vivo. To study these aspects, IBU was mixed at increasing weight ratios and in different chemical forms (free acid, sodium salt, and n-butyl ester), to investigate further the role of the carboxylic group in the interaction with the RL polymer. Therefore, IBU-RL solid dispersions (coevaporates) were obtained and fully characterized in the solid state through spectroscopic, calorimetric, and x-ray diffractometric analyses. The in vitro release pattern of the drug, in the different chemical states, was studied for the coevaporates, compared with drug-RL physical mixtures, along with drug adsorption profiles from aqueous solutions on the surface of the polymer granules.

Effect of liposomal delivery on in vitro antitumor activity of lipophilic conjugates of methotrexate with lipoamino acids.

Some selected lipophilic conjugates of the antifolate drug methotrexate (MTX) with lipoamino acids (LAA), previously described, were incorporated in liposomes with a different composition and charge (neutral, positive, or negative). The properties of the liposomal systems were determined. The inhibitory activity of the conjugates after incorporation in the vesicles was determined in a preliminary assessment against a human erythroleukemic cell line (K562 cells) and compared with the activity of the parent drug and of free conjugates. The influence of liposome surface charge and of the type of conjugate (i.e., in the carboxylic or ester form) on the biological effect is discussed.

Enhanced ocular anti-inflammatory activity of ibuprofen carried by an Eudragit RS100 nanoparticle suspension.

PURPOSE: To investigate the ocular pharmacodynamic profile of a polymer nanoparticle system loaded with sodium ibuprofen (IBU-RS) in comparison to an aqueous solution of ibuprofen lysinate (IBL) in the rabbit eye both being applied topically. METHODS: Ocular inflammation was elicited by topical application of sodium arachidonate. Inflammation was quantified according to a modified Draize test. The protein level and the number of polymorphonuclear leukocytes in the aqueous humor were assessed after 2 h from arachidonate instillation. The ibuprofen concentration in the aqueous humor was evaluated by HPLC assay. The physico-chemical properties of nanoparticles were also evaluated. RESULTS: The IBU-RS nanosuspension formulation significantly reduced the primary signs of ocular inflammation as well as significantly reducing the protein level and the number of polymorphonuclear leukocytes in the aqueous humor compared with the IBL formulation. Furthermore, the aqueous humor drug concentration from the group treated with IBU-RS was significantly higher compared to the IBL-treated group. The IBU-RS nanosuspensions showed very interesting size and surface charge values, adequate for ophthalmic administration. CONCLUSIONS: The pharmacological profile of the topical IBU-RS nanosuspension formulation described in this study indicates that the dispersion of the drug within RS polymer nanoparticles increased its ocular bioavailability and ultimately its pharmacological activity.