Rutin-loaded zein gel as a green biocompatible formulation for wound healing application.

Wound healing is a challenging clinical problem and efficient wound management is essential to prevent infection. This is best done by utilizing biocompatible materials in order to complete the healing in a rapid manner, with functional and esthetic outcomes. In this context, the zein protein fulfills the criteria of the ideal wound dressing which include non-toxicity and non-inflammatory stimulation. Zein gels containing rutin were prepared without any chemical refinement or addition of gelling agents in order to obtain a natural formulation characterized by antioxidant and anti-inflammatory properties to be proposed for the treatment of burns and sores. In vitro scratch assay showed that the proposed gel formulations promoted cell migration and a rapid gap closure within 24 h (~90 %). In addition, the in vivo activities of rutin-loaded zein gel showed a greater therapeutic efficacy in Wistar rats, with a decrease of the wound area of about 90 % at day 10 with respect to the free form of the bioactive and to DuoDERM®. The evaluation of various markers (TNF-α, IL-1ß, IL-6, IL-10) confirmed the anti-inflammatory effect of the proposed formulation. The results illustrate the feasibility of exploiting the peculiar features of rutin-loaded zein gels for wound-healing purposes.

DIFUCOSIN: DIclofenac sodium salt loaded FUCOidan-SericIN nanoparticles for the management of chronic inflammatory diseases.

The current investigation emphasizes the use of fucoidan and sericin as dual-role biomaterials for obtaining novel nanohybrid systems for the delivery of diclofenac sodium (DS) and the potential treatment of chronic inflammatory diseases. The innovative formulations containing 4 mg/ml of fucoidan and 3 mg/ml of sericin showed an average diameter of about 200 nm, a low polydispersity index (0.17) and a negative surface charge. The hybrid nanosystems demonstrated high stability at various pHs and temperatures, as well as in both saline and glucose solutions. The Rose Bengal assay evidenced that fucoidan is the primary modulator of relative surface hydrophobicity with a two-fold increase of this parameter when compared to sericin nanoparticles. The interaction between the drug and the nanohybrids was confirmed through FT-IR analysis. Moreover, the release profile of DS from the colloidal systems showed a prolonged and constant drug leakage over time both at pH 5 and 7. The DS-loaded nanohybrids (DIFUCOSIN) induced a significant decrease of IL-6 and IL-1ß with respect to the active compound in human chondrocytes evidencing a synergistic action of the individual components of nanosystems and the drug and demonstrating the potential application of the proposed nanomedicine for the treatment of inflammation.

Gliadin nanoparticles for oral administration of bioactives: Ex vivo and in vivo investigations.

This study aims to provide a thorough characterization of Brij O2-stabilized gliadin nanoparticles to be used for the potential oral administration of various compounds. Different techniques were used in order to evaluate their physico-chemical features and then in vivo studies in rats were performed for the investigation of their biodistribution and gastrointestinal transit profiles. The results showed that the gliadin nanoparticles accumulated in the mucus layer of the bowel mucosa and evidenced their ability to move along the digestive systems of the animals. The incubation of the nanosystems with Caenorhabditis elegans, used as an additional in vivo model, confirmed the intake of the particles and evidenced their presence along the entire gastrointestinal tract of these nematodes. The gliadin nanoparticles influenced neither the egg-laying activity of the worms nor their metabolism of lipids up to 10 µg/mL of nanoformulation. The systems decreased the content of the age-related lipofuscin pigment in the nematodes in a dose-dependent manner, demonstrating a certain antioxidant activity. Lastly, dihydroethidium staining showed the absence of oxidative stress upon incubation of the worms together with the formulations, confirming their safe profile. This data paves the way for the future application of the proposed nanosystems regarding the oral delivery of various bioactives.

Strategies of stabilization of zein nanoparticles containing doxorubicin hydrochloride.

Hybrid nanoparticles made up of zein and various stabilizers were developed and characterized. In detail, a zein concentration of 2 mg/ml was blended with various amounts of different phospholipids or PEG-derivatives in order to obtain formulations with suitable physico-chemical properties for drug delivery purposes. Doxorubicin hydrochloride (DOX) was used as a model of a hydrophilic compound and its entrapment efficiency, release profile and cytotoxic activity were investigated. Photon correlation spectroscopy showed that the best formulations were obtained using DMPG, DOTAP and DSPE-mPEG2000 as stabilizers of zein nanoparticles, which were characterized by an average diameter of ~100 nm, a narrow size distribution and a significant time- and temperature-dependent stability. The interaction between protein and stabilizers was confirmed through FT-IR analysis, while TEM analysis showed the presence of a shell-like structure around the zein core. The release profiles of the drug from the zein/DSPE-mPEG2000 nanosystems, evaluated at two pHs (5.5 and 7.4), showed a prolonged and constant leakage of the drug. The encapsulation of DOX within zein/DSPE-mPEG2000 nanosystems did not compromise its biological efficacy, demonstrating the potential application of these hybrid nanoparticles as drug carriers.

Characterization and Preliminary In Vitro Antioxidant Activity of a New Multidrug Formulation Based on the Co-Encapsulation of Rutin and the α-Acylamino-ß-Lactone NAAA Inhibitor URB894 within PLGA Nanoparticles.

A biodegradable and biocompatible polymeric matrix made up of poly(d,l-lactide-co-glycolide) (PLGA) was used for the simultaneous delivery of rutin and the (S)-N-(2-oxo-3-oxetanyl)biphenyl-4-carboxamide derivative (URB894). The goal was to exploit the well-known radical scavenging properties of rutin and the antioxidant features recently reported for the molecules belonging to the class of N-acylethanolamine-hydrolyzing acid amidase (NAAA) inhibitors, such as URB894. The use of the compounds, both as single agents or in association promoted the development of negatively-charged nanosystems characterized by a narrow size distribution and an average diameter of ~200 nm when 0.2-0.6 mg/mL of rutin or URB894 were used. The obtained multidrug carriers evidenced an entrapment efficiency of ~50% and 40% when 0.4 and 0.6 mg/mL of rutin and URB894 were associated during the sample preparation, respectively. The multidrug formulation evidenced an improved in vitro dose-dependent protective effect against H2O2-related oxidative stress with respect to that of the nanosystems containing the active compounds as a single agent, confirming the rationale of using the co-encapsulation approach to obtain a novel antioxidant nanomedicine.

Gliadin Nanoparticles Containing Doxorubicin Hydrochloride: Characterization and Cytotoxicity.

Doxorubicin hydrochloride (DOX) is a well-known antitumor drug used as first line treatment for many types of malignancies. Despite its clinical relevance, the administration of the compound is negatively affected by dose-dependent off-target toxicity phenomena. Nanotechnology has helped to overcome these important limitations by improving the therapeutic index of the bioactive and promoting the translation of novel nanomedicines into clinical practice. Herein, nanoparticles made up of wheat gliadin and stabilized by polyoxyethylene (2) oleyl ether were investigated for the first time as carriers of DOX. The encapsulation of the compound did not significantly affect the physico-chemical features of the gliadin nanoparticles (GNPs), which evidenced a mean diameter of ~180 nm, a polydispersity index < 0.2 and a negative surface charge. The nanosystems demonstrated great stability regarding temperature (25−50 °C) and were able to retain high amounts of drug, allowing its prolonged and sustained release for up to a week. In vitro viability assay performed against breast cancer cells demonstrated that the nanoencapsulation of DOX modulated the cytotoxicity of the bioactive as a function of the incubation time with respect to the free form of the drug. The results demonstrate the potential use of GNPs as carriers of hydrophilic antitumor compounds.

Oleic acid-based vesicular nanocarriers for topical delivery of the natural drug thymoquinone: Improvement of anti-inflammatory activity.

The topical administration of a drug compound remains the first choice for the treatment of many local skin ailments. Many skin diseases can be treated by applying the active formulation directly to the skin, but unfortunately some drugs are unable to overcome the stratum corneum and exert their pharmacological action. An example is thymoquinone, a naturally derived drug obtained from Nigella sativa L. and potentially effective in the treatment of inflammatory and oxidative skin conditions. Since its physico-chemical properties are not suitable for overcoming the stratum corneum, we wanted to circumvent the problem by proposing new lipid-based nanovesicles called "oleoethosomes", made up of naturally derived ingredients, for its delivery. Among several formulations of oleoethosomes, the sample made up of 2% (w/w) oleic acid:PL90G 1:1 (molar ratio), and ethanol 15% showed the best physico-chemical characteristics and above all it showed the capacity to contain a suitable amount of thymoquinone (2 mg/ml). The formulation was tested in vitro on stratum corneum and viable epidermis membranes confirming its ability to induce the passage of thymoquinone through the human stratum corneum and to act as a permeation enhancer. In fact, it showed thymoquinone permeation values of 22.63 ± 1.49% regarding the applied drug amount. Oleoethosomes were compared with oleosomes, another kind of naturally derived nanosystems but free of ethanol. The experimental data confirmed that ethanol was an important component that enhanced the activity of the oleoethosomes when tested on the skin of healthy volunteers. The thymoquinone-loaded oleoethosome treatment demonstrated a significantly greater extent of anti-inflammatory activity than the treatment with thymoquinone-loaded oleosomes or the conventional dosage form of the drug. These in vivo results confirmed the synergic effect between oleic acid and ethanol on the lipid and protein compartments of the outermost skin layer, thus promoting a greater penetration capacity.

Ascorbic acid-loaded gliadin nanoparticles as a novel nutraceutical formulation.

Ascorbic acid (AA) is one of the foremost antioxidants. Unfortunately, its sensitivity to different external stimuli such as light, heat and oxygen are concrete limitations for its use. Various approaches have been investigated in order to circumvent this problem and enhance the stability of the active compound, besides promoting its use for different applications. In this investigation, AA was encapsulated in a vegetal protein-based matrix made up of gliadin, the prolamin obtained from wheat kernels, with the aim of proposing a novel nutraceutical formulation. The nanosystems were characterized by an average diameter of < 200 nm and a negative surface charge of âˆ¼ -40 mV. The samples were not destabilized after incubation at different temperatures (up to 70 °C) or after the pasteurization procedure. Suitable stability was also observed in NaCl 100 mM, as well as after cryodesiccation when 10 % w/v of mannose was used. The gliadin nanoparticles showed the ability to retain high amounts of AA, promoting its prolonged release in PBS and under simulated gastrointestinal conditions. The nanosystems enhanced the antioxidant features of the compound as compared to its free form and preserved its chemical stability following UV exposition. The results demonstrate the potential application of the investigated nanoparticles as a novel nutraceutical formulation or as food fortificants.

Co-Encapsulation of Paclitaxel and JQ1 in Zein Nanoparticles as Potential Innovative Nanomedicine.

The manuscript describes the development of zein nanoparticles containing paclitaxel (PTX) and the bromo-and extra-terminal domain inhibitor (S)-tertbutyl2-(4-(4-chlorophenyl)-2,3,9-trimethyl-6H-thieno(3,2-f)(1,2,4)triazolo(4,3-a)(1,4)diazepin-6-yl)acetate (JQ1) together with their cytotoxicity on triple-negative breast cancer cells. The rationale of this association is that of exploiting different types of cancer cells as targets in order to obtain increased pharmacological activity with respect to that exerted by the single agents. Zein, a protein found in the endosperm of corn, was used as a biomaterial to obtain multidrug carriers characterized by mean sizes of ˂200 nm, a low polydispersity index (0.1-0.2) and a negative surface charge. An entrapment efficiency of ~35% of both the drugs was obtained when 0.3 mg/mL of the active compounds were used during the nanoprecipitation procedure. No adverse phenomena such as sedimentation, macro-aggregation or flocculation occurred when the nanosystems were heated to 37 °C. The multidrug nanoformulation demonstrated significant in vitro cytototoxic activity against MDA-MB-157 and MDA-MB-231 cancer cells by MTT-test and adhesion assay which was stronger than that of the compounds encapsulated as single agents. The results evidence the potential application of zein nanoparticles containing PTX and JQ1 as a novel nanomedicine.

Application of Biocompatible Drug Delivery Nanosystems for the Treatment of Naturally Occurring Cancer in Dogs.

BACKGROUND: Cancer is a common disease in dogs, with a growing incidence related to the age of the animal. Nanotechnology is being employed in the veterinary field in the same manner as in human therapy. AIM: This review focuses on the application of biocompatible nanocarriers for the treatment of canine cancer, paying attention to the experimental studies performed on dogs with spontaneously occurring cancer. METHODS: The most important experimental investigations based on the use of lipid and non-lipid nanosystems proposed for the treatment of canine cancer, such as liposomes and polymeric nanoparticles containing doxorubicin, paclitaxel and cisplatin, are described and their in vivo fate and antitumor features discussed. CONCLUSIONS: Dogs affected by spontaneous cancers are useful models for evaluating the efficacy of drug delivery systems containing antitumor compounds.

Repurposing of parenterally administered active substances used to treat pain both systemically and locally.

Pain is a constant in our lives. The efficacy of drug therapy administered by the parenteral route is often limited either by the physicochemical characteristics of the drug itself or its adsorption-distribution-metabolism-excretion (ADME) mechanisms. One promising alternative is the design of innovative drug delivery systems that can improve the pharmacokinetics |(PK) and/or reduce the toxicity of traditionally used drugs. In this review, we discuss several products that have been approved by the main regulatory agencies (i.e., nano- and microsystems, implants, and oil-based solutions), highlighting the newest technologies that govern both locally and systemically the delivery of drugs. Finally, we also discuss the risk assessment of the scale-up process required, given the impact that this approach could have on drug manufacturing. Teaser: The management of pain by way of the parenteral route can be improved using complex drug delivery systems (e.g., micro- and nanosystems) which require high-level assessment and shorten the regulatory pathway.

α-Acylamino-ß-lactone N-Acylethanolamine-hydrolyzing Acid Amidase Inhibitors Encapsulated in PLGA Nanoparticles: Improvement of the Physical Stability and Protection of Human Cells from Hydrogen Peroxide-Induced Oxidative Stress.

N-Acylethanolamine acid amidase (NAAA) is an N-terminal cysteine hydrolase that preferentially catalyzes the hydrolysis of endogenous lipid mediators such as palmitoylethanolamide, which has been shown to exhibit neuroprotective and antinociceptive properties by engaging peroxisome proliferator-activated receptor-α. A few potent NAAA inhibitors have been developed, including α-acylamino-ß-lactone derivatives, which are very strong and effective, but they have limited chemical and plasmatic stability, compromising their use as systemic agents. In the present study, as an example of a molecule belonging to the chemical class of N-(2-oxo-3-oxetanyl)amide NAAA inhibitors, URB866 was entrapped in poly(lactic-co-glycolic acid) nanoparticles in order to increase its physical stability. The data show a monomodal pattern and a significant time- and temperature-dependent stability of the molecule-loaded nanoparticles, which also demonstrated a greater ability to effectively retain the compound. The nanoparticles improved the photostability of URB866 with respect to that of the free molecule and displayed a better antioxidant profile on various cell lines at the molecule concentration of 25 µM. Overall, these results prove that the use of polymeric nanoparticles could be a useful strategy for overcoming the instability of α-acylamino-ß-lactone NAAA inhibitors, allowing the maintenance of their characteristics and activity for a longer time.

Influence of the Dispersion Medium and Cryoprotectants on the Physico-Chemical Features of Gliadin- and Zein-Based Nanoparticles.

The evaluation of the physico-chemical features of nanocarriers is fundamental because the modulation of these parameters can influence their biological and in vivo fate. This work investigated the feasibility of saline, 5% w/v glucose and phosphate-buffered saline solution, as polar media for the development of nanoparticles made up of two vegetal proteins, zein from corn and gliadin from wheat, respectively. The physico-chemical features of the various systems were evaluated using dynamic and multiple light scattering techniques, and the results demonstrate that the 5% w/v glucose solution is a feasible medium to be used for their development. Moreover, the best formulations were characterized by the aforementioned techniques following the freeze-drying procedure. The aggregation of the zein nanoparticles prepared in water or glucose solution was prevented by using various cryoprotectants. Mannose confirmed its crucial role in the cryopreservation of the gliadin nanosystems prepared in both water and glucose solution. Sucrose and glucose emerged as additional useful excipients when they were added to gliadin nanoparticles prepared in a 5% glucose solution. Specifically, their protective effect was in the following order: mannose > sucrose > glucose. The results obtained when using specific aqueous media and cryoprotectants permitted us to develop stable zein or gliadin nanoparticles as suspension or freeze-dried formulations.

SCLAREIN (SCLAREol contained in zeIN) nanoparticles: Development and characterization of an innovative natural nanoformulation.

Sclareol is a labdane diterpene which carries on a broad range of biological activities. However, its poor water solubility and bioavailability are the foremost drawbacks that limit its application in therapeutics. The purpose of this investigation was to develop a natural nanoformulation made up of a biopolymer i.e. zein and sclareol in order to address this issue and to enhance the pharmacological efficacy of the drug. The sclarein nanoparticles (sclareol-loaded zein nanosystems) showed a typical monomodal pattern, characterized by a mean diameter of ~120 nm, a narrow size distribution and a surface charge of ~-30 mV. The evaluation of the entrapment efficiency and the drug-loading capacity of the nanosystems demonstrated the noteworthy ability of the protein matrix to hold sclareol while allowing a gradual release of the compound over time. The nanosystems increased the cytotoxicity of sclareol at a drug concentration of ≥5 µM with respect to the free compound after just 24 h incubation against various cancer cell lines. Indeed, the interaction of tritiated sclarein formulations with cells showed a time-dependent cell uptake of the nanosystems commencing as early as 1 h from the onset of incubation, favouring a significant decrease of the efficacious concentration of the drug.

Phospholipid/zein hybrid nanoparticles as promising carriers for the protection and delivery of all-trans retinoic acid.

A totally biodegradable mixed system made up of phospholipids and zein was developed in order to effectively improve the photostability of all-trans retinoic acid (ATRA) preserving its pharmacological properties. Photon correlation spectroscopy showed that the formulation obtained using phospholipon 85G and zein at a ratio of 7:3 w/w was characterized by an average diameter of less than 200 nm, a narrow size distribution and a significant time- and temperature-dependent stability. The use of specific cryoprotectants such as mannose and glucose favoured the long-term storage of the nanocarriers after the freeze-drying procedure. The nanoparticles increased the stability of the ATRA against photochemical degradation with respect to the free drug and its antitumor effect was preserved as a consequence of the cell uptake of the colloidal systems. The results demonstrate the potential of the proposed hybrid nanosystems to provide a high level of stabilization for sensitive and labile antitumor compounds.

EtoGel for Intra-Articular Drug Delivery: A New Challenge for Joint Diseases Treatment.

Ethosomes® have been proposed as potential intra-articular drug delivery devices, in order to obtain a longer residence time of the delivered drug in the knee joint. To this aim, the conventional composition and preparation method were modified. Ethosomes® were prepared by using a low ethanol concentration and carrying out a vesicle extrusion during the preparation. The modified composition did not affect the deformability of ethosomes®, a typical feature of this colloidal vesicular topical carrier. The maintenance of sufficient deformability bodes well for an effective ethosome® application in the treatment of joint pathologies because they should be able to go beyond the pores of the dense collagen II network. The investigated ethosomes® were inserted in a three-dimensional network of thermo-sensitive poloxamer gel (EtoGel) to improve the residence time in the joint. Rheological experiments evidenced that EtoGel could allow an easy intra-articular injection at room temperature and hence transform itself in gel form at body temperature into the joint. Furthermore, EtoGel seemed to be able to support the knee joint during walking and running. In vitro studies demonstrated that the amount of used ethanol did not affect the viability of human chondrocytes and nanocarriers were also able to suitably interact with cells.

Meglumine Antimoniate-Loaded Aqueous-Core PLA Nanocapsules: Old Drug, New Formulation against Leishmania-Related Diseases.

Leishmaniasis is a human and animal disease endemic in tropical and subtropical areas treated by means of pentavalent antimony as first-line approach. Unfortunately, the formulations available on the market are characterized by significant side effects and a total remission of the disease is difficult to be obtained. The aim of this investigation is to describe the development and characterization of aqueous-core poly-l-lactide (PLA) nanocapsules containing glucantime (meglumine antimoniate, MA) with the aim of increasing the pharmacological efficacy of the active compound. The polymeric systems characterized by a mean diameter of ≈300 nm exert a great interaction with murine macrophages. MA-loaded PLA nanocapsules show a great antileishmanial activity on mice infected with Leishmania infantum with respect to the free drug, favoring a decrease of the administration times. The biodistribution profiles demonstrate a lower renal accumulation of MA after its nanoencapsulation and a significant increase of its plasmatic half-life. The parasite load evaluated by immunohistochemistry shows a significant decrease in liver, spleen, and kidneys when mice are treated with MA-loaded PLA nanocapsules especially after 45 days. The obtained results demonstrate the potential application of MA-loaded PLA nanocapsules as novel nanomedicine for the treatment of leishmaniasis.

Recent Advances of Taxol-Loaded Biocompatible Nanocarriers Embedded in Natural Polymer-Based Hydrogels.

The discovery of paclitaxel (PTX) has been a milestone in anti-cancer therapy and has promoted the development and marketing of various formulations that have revolutionized the therapeutic approach towards several malignancies. Despite its peculiar anti-cancer activity, the physico-chemical properties of PTX compromise the administration of the compound in polar media. Because of this, since the development of the first Food and Drug Administration (FDA)-approved formulation (Taxol®), consistent efforts have been made to obtain suitable delivery systems able to preserve/increase PTX efficacy and to overcome the side effects correlated to the presence of some excipients. The exploitation of natural polymers as potential materials for drug delivery purposes has favored the modulation of the bioavailability and the pharmacokinetic profiles of the drug, and in this regard, several formulations have been developed that allow the controlled release of the active compound. In this mini-review, the recent advances concerning the design and applications of natural polymer-based hydrogels containing PTX-loaded biocompatible nanocarriers are discussed. The technological features of these formulations as well as the therapeutic outcome achieved following their administration will be described, demonstrating their potential role as innovative systems to be used in anti-tumor therapy.