Nanostructured lipid dispersions for topical administration of crocin, a potent antioxidant from saffron (Crocus sativus L.)

© 2016 Elsevier B.V.Crocin, a potent antioxidant obtained from saffron, shows anticancer activity in in vivo models. Unfortunately unfavorable physicochemical features compromise its use in topical therapy.The present study describes the preparation and characterization of nanostructured lipid dispersions as drug delivery systems for topical administration of crocin and the evaluation of antioxidant and antiproliferative effects of crocin once encapsulated into nanostructured lipid dispersions.Nanostructured lipid dispersions based on monoolein in mixture with sodium cholate and sodium caseinate have been characterized by cryo-TEM and PCS. Crocin permeation was evaluated in vitro by Franz cells, while the oxygen radical absorbance capacity assay was used to evaluate the antioxidant activity. Furthermore, the antiproliferative activity was tested in vitro by the MTT test using a human melanoma cell line.The emulsification of monoolein with sodium cholate and sodium caseinate led to dispersions of cubosomes, hexasomes, sponge systems and vesicles, depending on the employed emulsifiers. Permeation and shelf life studies demonstrated that nanostructured lipid dispersions enabled to control both rate of crocin diffusion through the skin and crocin degradation. The oxygen radical absorbance capacity assay pointed out an interesting and prolonged antioxidant activity of crocin while the MTT test showed an increase of crocin cytotoxic effect after incorporation in nanostructured lipid dispersions.This work has highlighted that nanostructured lipid dispersions can protect the labile molecule crocin from degradation, control its skin diffusion and prolong antioxidant activity, therefore suggesting the suitability of nanostructured lipid dispersions for crocin topical administration

In Vitro Antioxidant Activity of Idebenone Derivative-Loaded Solid Lipid Nanoparticles

Idebenone (IDE) has been proposed for the treatment of neurodegenerative diseases involving mitochondria dysfunctions. Unfortunately, to date, IDE therapeutic treatments have not been as successful as expected. To improve IDE efficacy, in this work we describe a two-step approach: (1) synthesis of IDE ester derivatives by covalent linking IDE to other two antioxidants, trolox (IDETRL) and lipoic acid (IDELIP), to obtain a synergic effect; (2) loading of IDE, IDETRL, or IDELIP into solid lipid nanoparticles (SLN) to improve IDE and its esters’ water solubility while increasing and prolonging their antioxidant activity. IDE and its derivatives loaded SLN showed good physico-chemical and technological properties (spherical shape, mean particle sizes 23–25 nm, single peak in the size distribution, ζ potential values −1.76/−2.89 mV, and good stability at room temperature). In vitro antioxidant activity of these SLN was evaluated in comparison with free drugs by means of oxygen radical absorbance capacity (ORAC) test. IDETRL and IDELIP showed a greater antioxidant activity than IDE and encapsulation of IDE and its derivatives into SLN was able to prolong their antioxidant activity. These results suggest that loading IDETRL and IDELIP into SLN could be a useful strategy to improve IDE efficacy

Natural Antioxidant Polyphenols On Inflammation Management: Anti-glycation Activity Vs Metalloproteinases Inhibition.

The diet polyphenols are a secondary metabolites of plants able to act on inflammation process. Their anti-inflammatory activity is articulated through several mechanisms that are related to their antioxidative and radical scavengers properties. Our work is focused on a novel approach to inflammatory disease management, based on anti-glycative and matrix metalloproteinases (MMPs) inhibition effects, as a connected phenomena. To better understand these correlation, polyphenols Structure-Activity Relationship (SAR) studies were also reported. The antioxidant polyphenols inhibit the AGEs at different levels of the glycation process in the following ways: 1) prevention of Amadori adduct oxidation; 2) trapping reactive dycarbonyl compounds; 3) attenuation of receptor for AGEs (RAGE) expression. Moreover, several flavonoids with radical scavenging property showed also MMPs inhibition interact directly with MMPs or indirectly via radical scavengers and AGEs reduction. The essential polyphenols features involved in these mechanisms are C2-C3 double bond and number and position of hydroxyl, glycosyl and O-methyl groups. These factors induce a change in molecular planarity interfering with the hydrogen bond formation, electron delocalization and metal ion chelation. In particular, C2-C3 double bond improve the antioxidant and MMPs inhibition, while the hydroxylation, glycosylation and methylation induce a positive and negative correlation respectively

2-Benzisothiazolylimino-5-benzylidene-4-thiazolidinones as protective agents against cartilage destruction

We report the synthesis, the antioxidant and the inhibitory activity (IC50) on metalloproteinases (MMPs) 3 and 13 of 2-benzo[d]isothiazolylimino-5-benzylidene-4-thiazolidinones. Their potential as protective agents in osteoarthritis (OA) was evaluated by biological assays on chondrocytes cultures, stimulated by IL-1β. The chondroprotective capability, related both to antioxidant activity and to inhibition of MMPs, was studied in vitro, by determining nitric oxide production and glycosaminoglycans release. Moreover, selected derivatives 1h and 1g was studied for nuclear factor kappaB (NF-κB) inhibition by Western Blot analysis and for MMP-3 protein release using ELISA test. The structure-activity relationship of tested compounds demonstrates a favorable effect of the para substitution on the 5-benzilydene ring. Compound 1g shows a potent and selective activity on MMP-3 versus MMP-13. Accordingly, 1g possesses high antioxidant effect, NO lowering and GAGs restoring capability and also reduces the production of MMPs and NF-κB expression. Thus 1g can be considered as new potential chondroprotective agent

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

AbstractCrocin 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

Dynamic Olfactometry: evaluation of odour intensity and stability of Citronella Oil loaded Solid Lipid Nanoparticles

The Dynamic Olfactometry is a satisfactory method to determine objectively the odour concentration of volatile samples, using a human selected panel. The essential oils (EOs) are composed by lipophilic and highly volatile secondary plant metabolites, including terpenoids, phenol-derived aromatic and aliphatic components. The terpenoids are volatile organic compounds (VOCs) that undergo to oxidative and isomerizzation processes due to the air, light, moisture and high temperatures. Moreover, as a consequence of the high vapour tension of VOCs, the efficacy of EOs are very limited in the time. The Citronella Oil (C.O.) is used extensively as a source of perfumery chemicals or repellent substances, as citronellolal, citronellol and geraniol, that are responsible to their instability. The nanoencapsulation in drug delivery systems represents an efficient strategy to improve the stability and efficacy of EOs-based formulations. In this work the C.O. is formulated in solid lipid nanoparticles (SLNs), by ultrasonication method. The mean diameter (MD), polidispersity index (PDI) and zeta potential (PZ) of C.O. loaded SLN are determined immediately and after one month from production, showing a good long term stability. The aim of the work is the evaluation of odour concentration of C.O. free and loaded in SLN, in order to understand how the formulation can influence volatility, stability and release in SLN formulation. The Dynamic Olfactometry is performed, according to the regulation UNI EN 13725:2004. The results are expressed in OUE/m3 (European Odour Unit, OUE for m3), that represents the amount of odorant, evaporated in 1 m3 of neutral gas, inducing a physiological response, equal to a reference gas used, n-butanol, on a panel. The figure 1 and 2 showed the relationship between the odour intensity (OUE/m3) of the free oil and loaded in SLN, at 2.5% and 0.25%, respectively. The odour intensity is followed for 96 hours. After 24 hours, the odour intensity of free oil is not perceptible at both concentrations used. On the contrary, the odour intensity of C.O. loaded in SLN at 96 hours is 580 OUE/m3, at 2.5%, and 250 OUE/m3, at 0.25%. The obtained results for C.O. loaded in SLN at 2.5% and 0.25%, confirmed a prolonged and concentration-dependent effect of C.O. formulations

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

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 β-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

Formulative and stability studies of a Citrus extract to produce novel “healthy food"

A correct diet daily and many foods can improve overall health. Lately, is spreading the figure of the “nutraceutical baker“ that produces baked goods by nutraceutical flour with or without the addition of herbal extracts with healthy properties. The use of extracts in foods, requires particular attention due to the high baking temperatures that contribute to their degradation. In this work has been stabilized a Citrus fresh juice extract (ExC), with antioxidant, hypocholesterolemic and antidiabetic properties to produce “ healthy snacks”. To improve ExC stability, the analytical and technological properties of the extract have been studied and then spray-dried microparticles with 1% (ExC1) and 2% (ExC2) of sodium alginate (ALG) have been produced. The choice of ALG, a polymer present in “GRAS list”, is due to its stability to the high temperatures (over 200°C). Moreover, It can be used in synergy with ExC in dyslipidemic diseases. In fact, several studies showed that ALG is able to reduce the glucose excursions and the obesity [1]. To select the best formulation, ExC1 and ExC2 have been characterized in terms of “real stability” (ICH guidelines), stability at static (range 200°- 260°C in muffle) and at dynamic temperatures, according to the production lines of baked goods (235-240°C for 10 min in industrial oven). The antioxidant efficiency (ORAC assay) and the inhibition of metalloproteinase MMP-2 and -9 overexpress in dyslipidemic disease, has been also evaluated [2]. The antioxidant efficiency assay results showed that: 1) ExC loses the antioxidant potency at 2 h after “real stability” test, while ExC1 and ExC2 both slightly only reduce the antioxidant capacity of the extract in the early hours; 2) ExC1 and ExC2 preserved ExC activity at 6 h and 8 h respectively at static and dynamic temperature, with a better profile of ExC2 at dynamic temperature. The results showed that ALG is able to preserve the good antioxidant activity and the high inhibitory effect of ExC on both MMPs. Moreover, it is also able to protect ExC from degradation. On the basis of the stability and of the in vitro studies, ExC2 was selected to produce baked goods with healthy properties

4-Thiazolidinone Derivatives as MMP Inhibitors in Tissue Damage: Synthesis, Biological Evaluation and Docking Studies

Nine 2-(1,2-benzothiazol-3-yl)-N-(4-oxo-2-phenyl-1,3-thiazolidin-3-yl)propanamides combining a benzisothiazole and 4-thiazolidinone in one framework were designed and synthesized. The aim of the study was to verify their effectiveness to affect the inflammatory/oxidative process in which free oxygen and nitrite (ROS and RNS) radicals, inflammatory mediators, such as nuclear factor κB (NF-κB), and matrix metalloproteinases (MMPs) are involved. Docking studies of all the compounds were performed in order to explore their binding mode at the MMP-9 protein. An appreciable anti-inflammatory/potential wound healing effects of the tested compounds was highlighted. Derivative 23, bearing a 4-carboxyphenyl substituent at C2 of the 4-thiazolidinone ring, exhibited the highest activity, being able to inhibit MMP-9 at nanomolar level(IC50 = 40 nM)