A comparison between silicone-free and silicone-based emulsions: Technological features and in vivo evaluation.

OBJECTIVE: Nowadays, the use of silicones in cosmetic formulation is still controversial, given that "natural" or "biodegradable" components are preferred. Often, the exclusion and/or the discrimination of these excipients from cosmetic field are unmotivated because all things cannot be painted with the same brush. Hence, we want to bring to light and underline the advantages of including silicones in cosmetic emulsions, refuting and debunking some myths related to their use. METHODS: Silicone-free and silicone-based emulsions were obtained within an easy homogenization process. Droplet size distribution was assessed by laser diffraction particle size analyser Mastersizer 2000™, and by optical microscopy. The long-time stability profiles were investigated thanks to the optical analyser Turbiscan® Lab Expert. Diffusing wave spectroscopy (DWS) by Rheolaser Master™ and frequency sweep measurements by Kinexus® Pro Rotational Rheometer were carried out to assess a full rheological characterization. In vivo studies were carried out by the evaluation of Trans Epidermal Water Loss (TEWL) over time on healthy human volunteers. A skin feeling rating was collected from the same volunteers by questionnaire. RESULTS: From size distribution analysis, a better coherence of data appeared for silicone-based emulsion, as the size of the droplets was kept unchanged after 1 month, as well as the uniformity parameter. Morphological investigation confirmed a homogenous droplet distribution for both samples. Silicones enhanced the viscosity, compactness and strength of the cream, providing a suitable stability profile both at room temperature and when heated at 40°C. The solid-like viscoelastic behaviour was assessed in the presence of dynamic oscillatory stresses. The monitoring of TEWL over time demonstrated non-occlusive properties of emulsions containing silicones, the values of which were comparable to the negative control. Silicone-based emulsions gained higher scores from the volunteers in silkiness, freshness and softness features, while lower scores were obtained in greasiness compared to silicone-free emulsions. No cases of irritation were recorded by the candidates. CONCLUSION: The presence of specific silicones inside a cosmetic product improved its technological characteristics. The rheological identity and the stability feature showed the real suitability of prepared emulsion as a cosmetic product. Moreover, this study demonstrated that silicone-based emulsions are safe for the skin and did not cause skin occlusion. Improved skin sensations are registered by potential consumers when silicones are included in the formulation.

OBJECTIF: De nos jours, l'utilisation de silicones dans la formulation cosmétique reste controversée, étant donné que les ingrédients «naturels¼ ou «biodégradables¼ sont privilégiés. Souvent, l'exclusion et/ou la discrimination de ces excipients du domaine cosmétique ne sont pas motivées, parce que tous les éléments ne peuvent pas être logés à la même enseigne. Par conséquent, nous souhaitons mettre en évidence et souligner les avantages de l'inclusion des silicones dans les émulsions cosmétiques, tout en réfutant et en démystifiant certains mythes liés à leur utilisation. MÉTHODES: Des émulsions sans silicone et des émulsions à base de silicone ont été obtenues dans le cadre d'un processus d'homogénéisation facile. La distribution des tailles de gouttelettes a été évaluée par diffraction laser avec le granulomètre Mastersizer 2000™ et par microscopie optique. Les profils de stabilité à long terme ont été étudiés grâce à l'analyseur optique Turbiscan® Lab Expert. La spectroscopie par diffusion d'ondes (Diffusing Wave Spectroscopy, DWS) par le Rheolaser Master™ et les mesures de balayage de fréquence par le rhéomètre rotatif Kinexus® Pro ont été réalisées pour évaluer une caractérisation rhéologique complète. Des études in vivo ont été menées par le biais de l'évaluation de la perte d'eau transépidermique (PETE) au fil du temps sur des volontaires humains en bonne santé. Une évaluation de la sensation cutanée a été recueillie auprès des mêmes volontaires par le biais d'un questionnaire. RÉSULTATS: L'analyse de la distribution des tailles a révélé une meilleure cohérence des données pour l'émulsion à base de silicone, car la taille des gouttelettes a été maintenue inchangée après 1 mois, ainsi que le paramètre d'uniformité. L'investigation morphologique a confirmé une distribution homogène des gouttelettes pour les deux échantillons. Les silicones ont amélioré la viscosité, la densité et la résistance de la crème, offrant ainsi un profil de stabilité approprié aussi bien à température ambiante qu'après chauffage à 40°C. Le comportement viscoélastique analogue à celui d'un solide a été évalué en présence de contraintes oscillatoires dynamiques. Le suivi de la perte d'eau transépidermique (PETE) au fil du temps a établi des propriétés non occlusives des émulsions contenant des silicones, dont les valeurs étaient comparables à celles du contrôle négatif. Les émulsions à base de silicone ont obtenu des scores plus élevés chez les volontaires en termes de caractéristiques de douceur, de fraîcheur et de souplesse, tandis que des scores plus faibles ont été obtenus en termes d'onctuosité par rapport aux émulsions sans silicone. Aucun cas d'irritation n'a été enregistré chez les candidats. CONCLUSION: La présence de silicones spécifiques dans un produit cosmétique a amélioré ses caractéristiques technologiques. L'identité rhéologique et la caractéristique de stabilité ont montré la pertinence réelle d'une émulsion préparée en tant que produit cosmétique. De plus, cette étude a démontré que les émulsions à base de silicone sont sans danger pour la peau et n'ont provoqué aucune occlusion cutanée. Les consommateurs potentiels enregistrent une amélioration des sensations cutanées lorsque des silicones sont inclus dans la formulation.

Influence of Materials Properties on Bio-Physical Features and Effectiveness of 3D-Scaffolds for Periodontal Regeneration.

Periodontal diseases are multifactorial disorders, mainly due to severe infections and inflammation which affect the tissues (i.e., gum and dental bone) that support and surround the teeth. These pathologies are characterized by bleeding gums, pain, bad breath and, in more severe forms, can lead to the detachment of gum from teeth, causing their loss. To date it is estimated that severe periodontal diseases affect around 10% of the population worldwide thus making necessary the development of effective treatments able to both reduce the infections and inflammation in injured sites and improve the regeneration of damaged tissues. In this scenario, the use of 3D scaffolds can play a pivotal role by providing an effective platform for drugs, nanosystems, growth factors, stem cells, etc., improving the effectiveness of therapies and reducing their systemic side effects. The aim of this review is to describe the recent progress in periodontal regeneration, highlighting the influence of materials' properties used to realize three-dimensional (3D)-scaffolds, their bio-physical characteristics and their ability to provide a biocompatible platform able to embed nanosystems.

Poly(ethyl acrylate-co-methyl Methacrylate-co-trimethylammoniethyl methacrylate chloride) (Eudragit RS100) Nanocapsules as Nanovector Carriers for Phoenix dactylifera L. Seeds Oil: a Versatile Antidiabetic Agent.

Food waste valorization practices have gained considerable attention focusing on the conversion of the waste into valuable products. In this context, the present study provides an insight into a new Eudragit RS100 based nanosystem as a carrier of date palm (Phoenix dactylifera L.) seeds oil known for its an antidiabetic activity. A priori systematic study was carried out in order to understand the individual impact of all contributing factors considered by the nanoprecipitation method. Then, date seeds oil nanoparticles were prepared, characterized and analyzed for their in vitro inhibition activity against: α-amylase and α-glucosidase. The results showed that the developed nanoparticles had an average diameter around 207 nm, a ζ-potential of +59 mV, and an encapsulation efficiency equal to 97 ± 1% with a loading capacity of 0.48 mg·mg-1. The α-amylase and α-glucosidase IC50 were found to be 87.6 and 155.3 µg·mL-1, respectively. Therefore, this study may surely open new perspectives for the development of novel health-promoting plant oils loaded-nanocarriers for several purposes.

The Rheolaser Master™ and Kinexus Rotational Rheometer® to Evaluate the Influence of Topical Drug Delivery Systems on Rheological Features of Topical Poloxamer Gel.

Poloxamer 407 copolymer is a versatile and widely used thermo-reversible material. Its use has many advantages, such as bio-adhesion, enhanced solubilization of poorly water-soluble drugs and many applications fields like oral, rectal, topical, nasal drug administration. Hydrogels made up of Poloxamer 407 are characterized by specific rheological features, which are affected by temperature, concentration and presence of other compounds. A strategic approach in topical therapeutic treatments may be the inclusion of drug delivery systems, such as ethosomes, transfersomes and niosomes, into hydrogel poloxamer formulation. The evaluation of the interaction between colloidal carriers and the Poloxamer 407 hydrogel network is essential for a suitable design of an innovative topical dosage form. For this reason, the Rheolaser Master™, based on diffusing wave spectroscopy, and a Kinexus Rotational Rheometer were used to evaluate the influence of nanocarriers on the microrheological features of hydrogels. The advantages of the Rheolaser Master™ analyzer are: (i) its ability to determine viscoelastic parameter, without altering or destroying the sample and at rest (zero shear); (ii) possibility of aging analysis on the same sample. This study provide evidence that vesicular systems do not influence the rheological features of the gel, supporting the possibility to encapsulate an innovative system into a three-dimensional network.

Acronychiabaueri Analogue Derivative-Loaded Ultradeformable Vesicles: Physicochemical Characterization and Potential Applications.

Elastic and ultradeformable liposomes were synthesized and physicochemically characterized to make suitable topical formulations for delivering the anti-inflammatory and anticancer compound 3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoic acid. The average sizes of elastic and ultradeformable liposomes are below 300 nm, while the size distribution and Z-potential are below 0.3 and - 25 mV, respectively. The presence of 3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoic acid does not affect the physicochemical parameters of nanovesicles. Elastic and ultradeformable liposomes show a zero order release kinetic and are stable at room temperature for a long time with or without 3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoic acid. The ultradeformable liposomes are more deformable than elastic liposomes. These differences may depend on sodium cholate derivatives making nanoformulations. The 3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans-propenoic acid-loaded elastic and ultradeformable liposomes can provide innovative nanotherapeutics-based natural compounds for the potential treatment of cutanous inflammation.

Improved anti-breast cancer activity by doxorubicin-loaded super stealth liposomes.

PEGylation is currently used for the synthesis of stealth liposomes and to enhance the pharmacokinetic and biopharmaceutical properties of payloads. PEGylated dendron phospholipids can decrease the detachment of polyethylene glycol (PEG) from the liposomal surface owing to an increased hydrophobic anchoring effect on the phospholipid bilayer of liposomes and thus generating super stealth liposomes that are suitable for the systemic delivery of anticancer drugs. Herein, doxorubicin hydrochloride-loaded super stealth liposomes were studied for the treatment of breast cancer lung metastasis in an animal model. The results demonstrated that the super stealth liposomes had suitable physicochemical properties for in vivo administration and could significantly increase the efficacy of doxorubicin in breast cancer lung metastasis tumor-bearing mice compared to the free drug. The super stealth liposomes also increased doxorubicin accumulation inside the tumor tissue. The permanence of PEG on the surface of the super stealth liposomes favored the formation of a depot of therapeutic nanocarriers inside the tumor tissue by improving their permanence after stopping treatment. The doxorubicin-loaded super stealth liposomes increased the survival of the mouse tumor model. These promising results demonstrate that the doxorubicin-loaded super stealth liposomes could be an effective nanomedicine to treat metastatic breast cancer.

In vitro and in vivo trans-epidermal water loss evaluation following topical drug delivery systems application for pharmaceutical analysis.

The measurement of Trans-Epidermal Water Loss (TEWL) allows to evaluate the integrity of Stratum Corneum Epidermis (SCE) barrier after topical application of colloidal nanocarriers by using a non-invasive method. The temporarily modifications of SCE lipids are important for the passage of colloidal nanocarriers across the skin; this passage causes a modification of TEWL values. Niosomes, ethosomes®, and transfersomes® are used as topical drug delivery systems due to their biopharmaceutical properties, and capability to permeate intact through the SCE. In vitro and in vivo evaluation of TEWL values was studied for niosomes, ethosomes® and transfersomes® in occlusive and non-occlusive conditions. TEWL values in vivo, using healthy human volunteers, are ∼12 g/m2âˆ™× h for all nanoformulations after 72 h, due to the rearrangement of lipids forming the SCE membranes. Conversely, TEWL values of healthy human volunteers, that are topically treated with niosomes, ethosomes® and transfersomes®, in non-occlusive conditions, are ∼20 g/m2âˆ™× h. This data was lower than those obtained in occlusive conditions (∼35 g/m2âˆ™× h). In vitro studies agreed results which are obtained in occlusive conditions using healthy human volunteers. SCE lipids of the skin restore their native structure after 72 h of nanocarrier application. In vitro and in vivo results showed that niosomes, ethosomes®, and transfersomes® interact with the skin in a temporary and reversible mode, and they can be used as suitable colloidal nanocarriers to increase the percutaneous permeation of drugs after topical application without damaging the native structure of the skin.

Ammonium glycyrrhizate skin delivery from ultradeformable liposomes: A novel use as an anti-inflammatory agent in topical drug delivery.

Glycyrrhiza glabra L. is a native plant of Central and South-Western Asia that is also diffused in the Mediterranean area and contains several bioactive compounds such as: flavonoids, sterols, triterpene and saponins. Glycyrrhizin, containing glycyrrhizic and glycyrrhizinic acids has anti-inflammatory and antiallergic effects that are similar to corticosteroids. Ammonium glycyrrhizinate is a derivative salt of glycyrrhizic acid with similar anti-inflammatory activity that cannot pass through the skin due to its physicochemical properties and molecular weight. Although several nanoformulations, such as ethosomes, are designed to provide a systemic effect through a topical application, there are different limitations to the distribution inside the blood stream. For this reason, ultradeformable liposomes, or transfersomes, are selected to improve the topical delivery of drugs and allow the distribution of payloads in the blood stream because they pass intact through the stratum corneum epidermis barrier, due to the presence of sodium cholate, aqueous cutaneous gradient, and the rapid penetration of transfersomes by cutaneous tight junctions, thus allowing the systemic delivery of different therapeutic cargo in non-occlusive conditions. The aim of this work was the synthesis and physicochemical characterization of the ammonium glycyrrhizinate-loaded ultradeformable liposomes, the evaluation of drug release and permeation through stratum corneum and epidermis barrier. The in vivo anti-inflammatory effect of ammonium glycyrrhizinate-loaded ultradeformable liposomes was tested on human healthy volunteers. The results demonstrated that the ammonium glycyrrhizinate-loaded ultradeformable liposomes decreased the skin inflammation on the human volunteers and the resulting nanoformulations can be used as a potential topical drug delivery system for anti-inflammatory therapy. ☆Parts of these results were presented as a poster communication at the Recent Developments in Pharmaceutical Analysis 2019 (RDPA 2019), Chieti, Italy.

Design, synthesis and characterization of a PEGylated stanozolol for potential therapeutic applications.

Stanozolol (STZ) is a drug used to treat serious disorders like aplastic anemia and hereditary angioedema. It is also indicated as an adjunct therapy for the treatment of vascular disorders and growth failures. Encouraging results obtained using animal models demonstrated that STZ increases bone formation and mineralization, thus improving both density and biomechanical properties. Like natural androgens, such as TST and 5α-dihydrotestosterone (5α-DHT), STZ binds androgen receptor (AR) to activate AR-mediated signaling. Despite its therapeutic effects, this synthetic anabolic-androgenic steroid (AAS), or 5α-DHT derivative, due to its high lipophilicity, is poor soluble in water. Thus, to increase the water solubility and stability of STZ, as well as its bioavailability and efficacy, an innovative PEGylated STZ (STZ conjugated with (MeO-PEG-NH2)10kDa, (MeO-PEG-NH)10kDa-STZ) was synthesized. As confirmed by chromatography (RP-HPLC) and spectrometry (ATR-FTIR, 1H NMR, elemental CHNS(O) analysis, MALDI-TOF/TOF) analyses, a very pure, stable and soluble compound was obtained. Acetylcholinesterase (AChE) competitive ELISA demonstrated that the resulting PEGylated STZ competes against biological TST, especially at lower concentrations. Cytotoxicity of increasing concentrations (1, 10, 25 or 50 µM) of STZ and/or (MeO-PEG-NH)10kDa-STZ was also evaluated for up 80 h by performing the MTT assay on human osteosarcoma Saos-2 cells, which express AR and are responsive to STZ. PEGylation mitigated cytotoxicity of STZ, by increasing the cell viability values, especially at higher drug concentrations. Furthermore, these results suggest that (MeO-PEG-NH)10kDa-STZ is a promising and reliable drug to be used in clinical conditions in which TST is required.

Anticancer activity of all-trans retinoic acid-loaded liposomes on human thyroid carcinoma cells.

All-trans retinoic acid (ATRA) is an anti-tumor compound, exerting different anti-cancer effects on different types of cancer cells. Unfortunately, retinoids are also characterized by certain side effects following systemic administration, such as the burning of skin and general malaise. The highly variable degree of bioavailability of ATRA plus its tendency to induce its own destruction through metabolic degradation following oral treatment necessitate the development of alternative formulations. The aim of this work is to evaluate the physico-chemical properties of unilamellar, ATRA-containing liposomes and to investigate the cytotoxic activity of this potential nanomedicine on human thyroid carcinoma cells. Liposomes made up of DPPC/Chol/DSPE-mPEG2000 (6:3:1 molar ratio), characterized by a mean diameter of ∼200nm, a polydispersity index of 0.1 and a negative surface charge, were used as ATRA-carriers and their antiproliferative efficacy was investigated in comparison with the free drug on three different human thyroid carcinoma cell lines (PTC-1, B-CPAP, and FRO) through MTT-testing. The liposomes protected the ATRA against photodegradation and increased its antiproliferative properties due to the improvement of its cellular uptake. ATRA-loaded liposomes could be a novel formulation useful for the treatment of anaplastic thyroid carcinoma.

Interaction between PEG lipid and DSPE/DSPC phospholipids: An insight of PEGylation degree and kinetics of de-PEGylation.

The degree to which liposomes are PEGylated is the feature, which most influences the length of the presence of stealth liposomes in the bloodstream. In order to thoroughly investigate the maximum amount of DSPE-PEG2000 that can be used to stabilize stealth liposomes, these were synthesized at different concentrations of DSPE-PEG2000 and their physicochemical properties were investigated by using differential scanning calorimetry (DSC). The kinetics of PEGylation and de-PEGylation were performed by incubating non-stealth liposomes in a DSPE-PEG2000 suspension at different incubation times, and then analyzing the data using DSC and dynamic light scattering (DLS) techniques. The results demonstrated that DSPE-PEG2000 was self-assembled in the phospholipid bilayers, thus forming stealth liposomes. The different amounts of DSPE-PEG2000 in the bilayer triggered a de-PEGylation phenomenon, resulting in mixed nanoaggregates, which derived from the detergent-like properties of the PEGylated phospholipids.

Delivery of miR-34a by chitosan/PLGA nanoplexes for the anticancer treatment of multiple myeloma.

The encapsulation of miR-34a into chitosan/PLGA nanoparticles in order to obtain nanoplexes useful for the modulation of the biopharmaceutical features of the active compound was studied. The nanoplexes were obtained through nanoprecipitation and were characterized by a mean diameter of ~160 nm, a good size distribution and a positive surface charge. The structure of the nanoparticles allowed a high level of entrapment efficiency of the miR-34a and provided protection of the genetic material from the effects of RNase. A high degree of transfection efficiency of the nanoplexes and a significant in vitro antitumor effect against multiple myeloma cells was demonstrated. The therapeutic properties of the nanoplexes were evaluated in vivo against human multiple myeloma xenografts in NOD-SCID mice. The systemic injection of miR-34a mimic-loaded nanoparticles significantly inhibited tumor growth and translated into improved survival of the laboratory mice. RT-PCR analysis carried out on retrieved tumors demonstrated the presence of a high concentration of miR-34a mimics. The integrity of the nanoplexes remained intact and no organ toxicity was observed in treated animals.