Freeze-Dried Softisan® 649-Based Lipid Nanoparticles for Enhanced Skin Delivery of Cyclosporine A.
ABSTRACT: Inflammatory skin diseases, including psoriasis and atopic dermatitis, affect around one quarter to one third of the world population. Systemic cyclosporine A, an immunosuppressant agent, is included in the current therapeutic armamentarium of these diseases. Despite being highly effective, it is associated with several side effects, and its topical administration is limited by its high molecular weight and poor water solubility. To overcome these limitations, cyclosporine A was incorporated into solid lipid nanoparticles obtained from Softisan® 649, a commonly used cosmetic ingredient, aiming to develop a vehicle for application to the skin. The nanoparticles presented sizes of around 200 nm, low polydispersity, negative surface charge, and stability when stored for 8 weeks at room temperature or 4 °C. An effective incorporation of 88% of cyclosporine A within the nanoparticles was observed, without affecting its morphology. After the freeze-drying process, the Softisan® 649-based nanoparticles formed an oleogel. Skin permeation studies using pig ear as a model revealed low permeation of the applied cyclosporine A in the freeze-dried form of the nanoparticles in relation to free drug and the freshly prepared nanoparticles. About 1.0 mg of cyclosporine A was delivered to the skin with reduced transdermal permeation. These results confirm local delivery of cyclosporine A, indicating its promising topical administration.
Project description:Cyclosporine A (CsA) is an immunosuppressant frequently used in the therapy of autoimmune disorders, including skin-related diseases. Aiming towards topical delivery, CsA was successfully incorporated into lipid nanoparticles of Lipocire DM and Pluronic F-127 using the hot homogenization method. Two different nanocarriers were optimized: solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) where oleic acid was the liquid lipid. The developed nanoparticles showed mean sizes around 200 nm, a negative surface charge, and drug entrapment efficiencies around 85% and 70% for SLNs and NLCs, respectively. The spherical CsA-loaded lipid nanoparticles were stable for 9 weeks when stored at room temperature, and exhibited in vitro pH-dependent release under skin mimetic conditions, following the Peppas-Korsmeyer model. CsA, when loaded in SLNs, was safe to be used up to 140 ?g mL<sup>-1</sup> in fibroblasts and keratinocytes, while CsA-loaded NLCs and free drug exhibited IC<sub>50</sub> values of 55 and 95 ?g mL<sup>-1</sup> (fibroblasts) and 28 and 30 ?g mL<sup>-1</sup> (keratinocytes), respectively. The developed SLNs were able to retain the drug in pork skin with a reduced permeation rate in relation to NLCs. These findings suggest that SLNs are a potential alternative to produce stable and safe CsA nanocarriers for topical administration.
Project description:INTRODUCTION:Skin fragility and recurrent wounds are hallmarks of hereditary epidermolysis bullosa (EB). Treatment options to accelerate wound healing are urgently needed. Oleogel-S10 contains a betulin-rich triterpene extract from birch bark. In this study, we tested the wound healing properties of topical Oleogel-S10 in patients with dystrophic EB. METHODS:We conducted an open, blindly evaluated, controlled, prospective phase II pilot trial in patients with dystrophic EB (EudraCT number 2010-019945-24). Healing of wounds treated with and without topical Oleogel-S10 was compared. Primary efficacy variable was faster reepithelialization as determined by 2 blinded experts. The main secondary outcome variable of the study was percentage of wound epithelialization. RESULTS:Twelve wound pairs of 10 patients with dystrophic EB were evaluated. In 5 of 12 cases, both blinded reviewers considered epithelialization of the intervention wounds as superior. In 3 cases, only one reviewer considered Oleogel-S10 as superior and the other one as equal to control. Measurements of wound size showed a trend towards accelerated wound healing with the intervention but without reaching statistical significance. CONCLUSION:Our results indicate a potential for faster reepithelialization of wounds in patients with dystrophic EB when treated with Oleogel-S10 but larger studies are needed to confirm significance.
Project description:AIM: To investigate the in vitro and in vivo percutaneous absorption of seleno-L-methionine (Se-L-M), an ultraviolet (UV)-protecting agent, from aqueous solutions. METHODS: Aqueous solutions of Se-L-M were prepared in pH 4, 8, and 10.8 buffers. The pH 8 buffer contained 30% glycerol, propylene glycol (PG) and polyethylene glycol (PEG) 400. The in vitro skin permeation of Se-L-M via porcine skin and nude mouse skin was measured and compared using Franz diffusion cells. The in vivo skin tolerance study was performed, which examined transepidermal water loss (TEWL), skin pH and erythema. RESULTS: In the excised porcine skin, the flux was 0.1, 11.4 and 8.2 μg·cm(-2)·h(-1) for the pH 4, 8, and 10.8 buffers, respectively. A linear correlation between the flux and skin deposition was determined. According to permeation across skin with different treatments (stripping, delipidation, and ethanol treatments), it was determined that the intracellular route comprised the predominant pathway for Se-L-M permeation from pH 8 buffer. Aqueous solutions of seleno-DL-methionine (Se-DL-M), selenium sulfide and selenium-containing quantum dot nanoparticles were also used as donor systems. The DL form showed a lower flux (7.0 vs 11.4 μg·cm(-2)·h(-1)) and skin uptake (23.4 vs 47.3 μg/g) as compared to the L form, indicating stereoselective permeation of this compound. There was no or only negligible permeation of selenium sulfide and quantum dots into and across the skin. With in vivo topical application for 4 and 8 h, the skin deposition of Se-L-M was about 7 μg/g, and values were comparable to each other. The topical application of Se-L-M for up to 5 d did not caused apparent skin irritation. However, slight inflammation of the dermis was noted according to the histopathological examination. CONCLUSION: Se-L-M was readily absorbed by the skin in both the in vitro and in vivo experiments. The established profiles of Se-L-M skin absorption will be helpful in developing topical products of this compound.
Project description:Chitosan nanoparticles have gained attention as drug delivery systems (DDS) in the medical field as they are both biodegradable and biocompatible with reported antimicrobial and anti-leishmanial activities. We investigated the application of chitosan nanoparticles as a DDS for the treatment of cutaneous leishmaniasis (CL) by preparing two types of chitosan nanoparticles: positively charged with tripolyphosphate sodium (TPP) and negatively charged with dextran sulphate. Amphotericin B (AmB) was incorporated into these nanoparticles. Both types of AmB-loaded nanoparticles demonstrated in vitro activity against Leishmania major intracellular amastigotes, with similar activity to unencapsulated AmB, but with a significant lower toxicity to KB-cells and red blood cells. In murine models of CL caused by L. major, intravenous administration of AmB-loaded chitosan-TPP nanoparticles (Size = 69 ± 8 nm, Zeta potential = 25.5 ± 1 mV, 5 mg/kg/for 10 days on alternate days) showed a significantly higher efficacy than AmBisome® (10 mg/kg/for 10 days on alternate days) in terms of reduction of lesion size and parasite load (measured by both bioluminescence and qPCR). Poor drug permeation into and through mouse skin, using Franz diffusion cells, showed that AmB-loaded chitosan nanoparticles are not appropriate candidates for topical treatment of CL.
Project description:l-ascorbic acid (AA), commonly known as vitamin C, has been widely used in topical formulations for many years as an antioxidant and anti-aging ingredient. However, the physicochemical properties of AA are not optimal for skin uptake and the molecule is also unstable, readily undergoing oxidation on exposure to air. The compound 3-o-ethyl-l-ascorbic acid (EA) has been developed as a stable vitamin C derivative and has been used in topical products. The aims of this work were to conduct a comprehensive characterisation of physicochemical properties of EA as well as to investigate the influence of various neat solvents on EA skin delivery. Nuclear magnetic resonance (NMR), mass spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to characterise the molecule. The pK<sub>a</sub> of the compound and the partition coefficient logP<sub>(o/w)</sub> were experimentally determined. A new HPLC method for analysis of the molecule was also developed and validated. A number of solvents for topical preparations were selected based on their wide use as excipients in topical formulations, their potential to act as skin penetration enhancers and their favourable safety profiles. The solubility and stability of EA was examined. Skin permeation of the molecule in full thickness porcine skin <i>in vitro</i> was investigated using Franz-type diffusion cells. The melting point, log P<sub>(o/w)</sub> value and pK<sub>a</sub> value of EA were determined to be 114.39?±?0.5?°C, -1.07?±?0.03 and 7.72?±?0.01 respectively. Skin penetration of EA was evident for the following vehicles 1,2 hexanediol (HEX), glycerol (GLY), propylene glycol (PG), 1,2 pentanediol (1-2P), isopropyl alcohol (IPA), propylene glycol monolaurate (PGML) and propylene glycol monocaprylate (PGMC). Skin uptake but no permeation through the skin was observed for Transcutol® (TC) and dipropylene glycol (DiPG), while no penetration was observed for the solvents 1,5 pentanediol (1-5P) and tripropylene glycol (TriPG). The findings of the permeation experiments confirm the potential of simple formulations to deliver EA to the skin. Studies are ongoing to identify complex vehicles for synergistic enhancement of EA skin penetration. To our knowledge this is the first study to conduct a comprehensive characterization of EA and examine its skin uptake and permeation properties in porcine skin.
Project description:PURPOSE: We investigate the efficacy of 0.03% topical tacrolimus eyedrops for the treatment of dry eye in graft versus host disease (GVHD) patients resistant/intolerant to 0.05% topical cyclosporine. METHODS: Forty-three patients were enrolled in this prospective study. After completing a 1-year run-in period of using artificial tears, 50% autologous serum eyedrops, and punctal plug occlusion, all the symptomatic patients (n=29) were treated with 0.05% topical cyclosporine (Restasis(®); Allergan, Inc.). After 1 month, the patients who presented topical or systemic intolerance to cyclosporine were instructed to instill 0.03% topical tacrolimus once a day for 3 months (n=14). All the patients were allowed to continue with their basal dry eye treatment. Visual acuity, fluorescein staining, Schirmer test, fluorescein tear break-up time, and tear meniscus height measurement were evaluated fortnightly (minimum 3 months). Subjective assessments of symptoms were also reported at the beginning and at the end of the study. RESULTS: Dry eye symptoms and signs improved statistically (P<0.05) and significantly with tacrolimus and cyclosporine topical treatment. No significant differences were observed between both the groups. The mean follow-up time was 12.14±2.69 months (range 10-18 months). CONCLUSION: The findings of this prospective pilot study suggest that cyclosporine-intolerant patients with dry eye associated with GVHD can be effectively treated with topical tacrolimus.
Project description:BACKGROUND:Chronic dry eye disease often requires long-term therapy. Tear film alterations in the setting of dry eye may include reduced tear volume as well as an increase in inflammatory cytokines and osmolarity. Topical cyclosporine ophthalmic emulsion 0.05% (Restasis(®); Allergan Inc, Irvine, CA) is indicated to increase tear production in patients with dry eye and reduced tear production presumed to be due to ocular inflammation. This study was designed to evaluate the efficacy of a second trial of topical cyclosporine in patients with dry eye who were previously considered treatment failures. MATERIALS AND METHODS:This multicenter (three cornea practices) retrospective chart review evaluated clinical outcomes in patients with dry eye who received a second trial of cyclosporine after a prior treatment failure, defined as prior discontinuation of topical cyclosporine after less than 12 weeks. RESULTS:Thirty-five patients, most of whom were female (71.4%) and Caucasian (62.9%), were identified. Prior discontinuation was most commonly due to burning/stinging (60%). The median duration of second treatment was 10 months (range 1 week to 45 months). Physician education was provided in the second trial in 97.1% of cases. At initiation of the second trial of cyclosporine, 10 (28.6%) patients received courses of topical corticosteroids. Physicians reported on a questionnaire that 80% of patients achieved clinical benefit with a second trial of cyclosporine. CONCLUSION:A repeat trial with topical cyclosporine can achieve clinical success. Direct patient education via the physician and staff may be key to success. Proper patient education may overcome adherence issues, particularly with respect to the need for long-term treatment of chronic dry eye. This study has the usual limitations associated with a retrospective chart review, and future prospective studies are warranted.
Project description:Cell-free DNA (cfDNA) released from damaged or dead cells combines with LL37 and is converted into an immune response activator to exacerbate psoriasis. Here, we show that cationic nanoparticles (cNPs) efficiently compete for DNA from the DNA-LL37 immunocomplex and inhibit DNA-LL37-induced cell activation. Using phenotypical images, psoriasis area and severity index scoring, histology, and immunohistochemical analysis, we demonstrate that topical application of cNPs on psoriasiform skin of a mouse model relieves psoriatic symptoms. It is noteworthy that the results were confirmed in a cynomolgus monkey model. Moreover, topically administrated cNPs showed low in vivo toxicity because of their retention in skin. Mechanistic analyses of cytokine expression in the psoriatic site, cfDNA levels in circulation and inflamed skin, skin permeation, and biodistribution of cNPs also matched the therapeutic outcomes. Therefore, we present a previously unidentified strategy of nanomedicine to treat skin inflammatory diseases, which demonstrates great potential for clinical application.
Project description:AIM: Silibinin (SB), silydianin (SD), and silychristin (SC) are components of silymarin. These compounds can be used to protect the skin from oxidative stress induced by ultraviolet (UV) irradiation and treat it. To this end, the absorption of silymarin constituents via the skin was examined in the present report. METHODS: Transport of SB, SD, and SC under the same thermodynamic activity through and into the skin and the effects of pH were studied in vitro using a Franz diffusion assembly. RESULTS: The lipophilicity increased in the order of SC<SD<SB. Increased lipophilicity of a compound resulted in higher skin deposition but had a minor effect on permeation across the skin in the less-ionized form (pH 8). It is apparent that compounds in the less-ionized form showed higher skin uptake compared to the more-ionized form. Hyperproliferative skin produced by UVB exposure showed increased permeation of silymarin constituents in the less-ionized form, but it did not affect deposition within the skin. With in vivo topical application for 4 and 8 h, the skin deposition of SB was higher than those of SD and SC by 3.5 approximately 4.0- and 30 approximately 40-fold, respectively. The skin disruption and erythema test demonstrated that the topical application of these compounds for up to 24 h caused no apparent skin irritation. CONCLUSION: The basic profiles of silymarin permeation via skin route were established.
Project description:A synergistic approach by the combination of magnetic nanoparticles with an alternating magnetic field for transdermal drug delivery was investigated. Methotrexate-loaded silk fibroin magnetic nanoparticles were prepared using suspension-enhanced dispersion by supercritical CO2. The physiochemical properties of the magnetic nanoparticles were characterized. In vitro studies on drug permeation across skin were performed under different magnetic fields in comparison with passive diffusion. The permeation flux enhancement factor was found to increase under a stationary magnetic field, while an alternating magnetic field enhanced drug permeation more effectively; the combination of stationary and alternating magnetic fields, which has a massage-like effect on the skin, achieved the best result. The mechanistic studies using attenuated total reflection Fourier-transform infrared spectroscopy demonstrate that an alternating magnetic field can change the ordered structure of the stratum corneum lipid bilayers from the gel to the lipid-crystalline state, which can increase the fluidity of the stratum corneum lipids, thus enhancing skin penetration. Compared with the other groups, the fluorescence signal with a bigger area detected in deeper regions of the skin also reveals that the simulated massage could enhance the drug permeation across the skin by increasing the follicular transport. The combination of magnetic nanoparticles with stationary/alternating magnetic fields has potential for effective massage-like transdermal drug delivery.