Containing Cyclosporin A Research Articles

Therapeutic Effects of 30 nm Cyclosporin A-Loaded Nanoparticles Using PLGA-PEG-PLGA Triblock Copolymer for Transdermal Delivery in Mouse Models of Psoriasis

This study aimed to evaluate the effectiveness of poly(DL-lactide-co-glycolide)-block-poly(ethylene glycol)-block-poly(DL-lactide-co-glycolide) triblock copolymers (PLGA-PEG-PLGA) as a drug carrier in the treatment of psoriasis. Nanoparticles containing cyclosporin A (CsA) were prepared, and their cytotoxicity and skin irritation properties were investigated. These results revealed that the nanoparticles themselves had no obvious cytotoxicity or skin irritation effects. Furthermore, it was shown that loading CsA into nanoparticles promoted its cellular uptake. The therapeutic effect of CsA-loaded PLGA-PEG-PLGA nanoparticles on psoriasis was evaluated using a mouse model of psoriasis induced by imiquimod. In psoriatic skin, we confirmed that nanoparticles penetrate deep into the skin. Furthermore, it was suggested that by using PLGA-PEG-PLGA, drug carriers could reach the dermal layer, which is the target site for psoriasis treatment. The observation of skin sections after the treatment experiment showed that excessively proliferated keratinocytes were restored to an almost normal state by using PLGA-PEG-PLGA nanoparticles as drug carriers. Additionally, the quantitative measurement results for cytokines revealed that the levels of TNF-α, IL-17A, and IL-22 were significantly decreased compared with those of the group to which CsA suspended in a 20% ethanol solution was administered. These results indicate that PLGA-PEG-PLGA nanoparticles are promising drug carriers for the transdermal administration of CsA.

Optimisation of PCL-HA laden biodegradable nanoparticles containing cyclosporine-A for the treatment of dry eye syndrome: in vitro-in vivo evaluation

The purpose of the present study is to develop polycaprolactone (PCL)-hyaluronic acid (HA) laden biodegradable nanoparticles containing cyclosporine-A (CsA) and sustained the release for ophthalmic delivery. The nanoparticles (NPs) were prepared by solvent diffusion technique followed lyophilisation. Optimisation of product variables for nanoparticles was done by central composite design (CCD) with particle size and entrapment efficiency as chosen responses. The developed formulation consisting 1.18% polycaprolactone and 0.16% hyaluronic acid showed 376.6 nm, −0.438 ± 0.137 mV and 40.945 ± 1.561% particle size, zeta potential and entrapment efficiency respectively. However, this formulation was efficient in controlling the drug release in-vitro as well, i.e., 92.59 ± 0.05% cyclosporine-A release at 24 hours. Surface morphology revealed nanoparticles were spherical in shape. Ocular irritancy study showed that formulation was safe and non-irritant. The Cmax of plain drug and biodegradable nanoparticles was found to be 15.802 mg at 6 hrs (mean residence time - MRT) and 19.447 mg at 8 hrs respectively. Area under the curve (AUC) was found to be 79.26 and 113.0 for plain drug and NPs formulation.

Cyclosporine A/porous quaternized chitosan microspheres as a novel pulmonary drug delivery system

N-[(2-Hydroxyl)-propyl-3-trimethyl ammonium] chitosan chloride (HTCC), a hydrosoluble chitosan derivative, has been extensively investigated as a class of drug delivery vehicles because of its unique features. However the studies on HTCC for pulmonary delivery systems have been rarely conducted. This study aimed to design porous microspheres (MS) containing cyclosporine A (CsA) using HTCC as the carrier. The physicochemical properties and biocompatibility of the MS were evaluated. The in vivo efficacy of MS was evaluated in an asthmatic rat model after pulmonary administration. The results showed that porous MS suitable for inhalation could be readily produced by spray drying method. Optimized porous MS in this study exhibited to be biocompatible and safe to use in the lung, and they were effective in suppression of inflammation in the asthmatic rat model. Above all, our results suggested that HTCC porous MS are promising drug carriers for pulmonary drug delivery.

Local dermal delivery of cyclosporin A, a hydrophobic and high molecular weight drug, using dissolving microneedles

Dissolving microneedles (MN) containing cyclosporin A (CyA) were prepared for local delivery of CyA into the dermal layer. The efficacy of using MN to deliver CyA, an insoluble and high molecular weight drug, was observed and compared with oral administration of solubilized CyA.Microneedles containing CyA (CyA MN) were prepared using a closed, low-temperature molding process. The mechanical properties of CyA MN and phase separation were studied regarding the content of CyA. CyA MN were inserted into porcine skin for a predetermined time, and the dissolution and delivered amount of CyA were measured in vitro with an optical microscope and high-performance liquid chromatography (HPLC) analysis of the extracted CyA. A pharmacokinetic study of CyA MN was performed in vivo by administering 10% CyA MN, and the pharmacokinetic profile was compared with that of orally administered CyA.Pyramidal CyA MN (600 μm long, 250 μm wide) were prepared. CyA MN penetrated skin successfully with up to 50% CyA content. When 10% CyA MN were pressed into porcine skin for 60 min, 65% of MN length was dissolved and 34 ± 6.5 μg of CyA in MN was delivered into the skin. Under the same conditions with 10% CyA MN administered to rats, CyA MN showed Tmax of 8 h, Cmax of 15.9 ng/ml, and area under curve (AUC) of 686, compared to Tmax of 2 h, Cmax of 18.205 ng/ml, and AUC of 254 for oral administration of solubilized CyA.A therapeutic dose of CyA for treatment of psoriasis was delivered via MN into the skin layer without solubilization of CyA. Due to the hydrophobic properties and high molecular weight of CyA, the safety of CyA delivery was improved using dissolving microneedles because the slow systemic absorption and local treatment enabled CyA to remain in the skin for a longer time. Microneedles are an effective method with high bioavailability for local dermal delivery of insoluble drugs.

Development of cyclosporine A-loaded dry-emulsion formulation using highly purified glycerol monooleate for safe inhalation therapy

The main objective of this study was to improve the safety and oxidative stability of glycerol monooleate (GMO)-based dry-emulsion (DE) formulation containing cyclosporine A (CsA) for inhalation therapy. GMO or highly purified GMO (hpGMO) was used as surfactant for the DE formulations (GMO/DE or hpGMO/DE), the toxicological and physicochemical properties of which were characterized with a focus on oxidative stability, in vitro/in vivo toxicity, and dissolution property. Incubation of GMO at oxidation accelerating conditions for 10 days at 60°C resulted in the formation of lipid peroxides as evidenced by increased malondialdehyde (111 μmol/mg); however, hpGMO samples exhibited increase of only 20.7 μmol/mg in malondialdehyde level. No significant acute cytotoxicity was observed in rat alveolar L2 cells exposed to hpGMO (0.28mM), and intratracheal administration of hpGMO powder in rats did not cause an increase of the plasma LDH level. The hpGMO/DE exhibited marked improvement in dissolution behavior of CsA, and stable fine micelles with a mean diameter of 320 nm were formed when suspended in water. A respirable powder formulation of hpGMO/DE (hpGMO/DE-RP) was newly prepared, and its in vitro inhalation property and in vivo efficacy were also evaluated. The hpGMO/DE-RP exhibited high dispersibility in laser diffraction analysis and significantly improved potency to attenuate recruitment of inflammatory cells into airway and thickening of airway wall in an animal model. Thus, the strategic use of hpGMO would improve oxidative stability and local toxicity compared with a GMO-based DE formulation, and its application to RP formulation could be a promising approach for effective inhalation therapy.

Local administration of chitosan microspheres after traumatic brain injury in rats: a new challenge for cyclosporine – a delivery

The major aim of this study was to evaluate the efficiency of chitosan microspheres containing cyclosporine-A (Cs-A) on mitochondrial damage in traumatic brain injury (TBI) animal model. Trauma was introduced to male Sprague-Dawley (SD) rats similar to that of modified Feeney Method. Briefly, after craniectomy in the left parietal region (5 mm). Trauma was performed by dropping 24 g metal sterile rods through a teflon guide tube (9.3 cm) on a foot plate placed over the duramater. Just after the trauma, 20 mg/kg Cs-A (Sandimmune®) has been administered to the traumatised SD rats intraperitoneally (i.p.). On the other hand, only chitosan microspheres containing 10 mg/kg was implanted at the craniectomy area locally after trauma in Group E. A small piece of surgicell was placed over the craniectomy hole and the scalp incision was sutured. 24 h after injury and the brain tissues were removed intact. The results were evaluated through lipid peroxidation ratio and ultrastructural grading system. The statistical comparisons were evaluated by using Mann Whitney– U test at the significance level p = 0.05. The lipid peroxidation ratios of sham (78.4 ± 6.0 nmol/g tissue) and vehicle (80.2 ± 10.6 nmol/g tissue) were significantly increased 24 h after TBI. However, for treatment groups (i.p. Cs-A; 20 mg/kg) and (10 mg/kg Cs-A in microspheres), statistically significant lower lipid peroxidation ratios were determined as 53.5 ± 9.7 and 47.9 ± 8.1 nmol/g tissue, respectively (p < 0.05). The mitochondrial damage scores of the treatment groups were recorded as 21.7 ± 2.6 and 19.4 ± 3.9 for Group D and Group E, respectively. Both of these scores of the treatment groups were found as significantly different from the sham and vehicle groups' scores individually. The implantation of microsphere formulation has provided a better efficiency in keeping the uniformity of mitochondrial structure in this complex cascade of events after TBI.

Preparation, Characterization, and Mucoadhesive Properties of Chitosan-Coated Microspheres Encapsulated with Cyclosporine A

The aim of this study was to prepare and characterize chitosan-coated microspheres containing cyclosporine A (CyA). Microspheres encapsulated with CyA were prepared by solvent evaporation-emulsification methods. Microspheres were immersed in chitosan solution (0.5% w/w) to be coated. Morphology, mean size, and encapsulation efficiency of chitosan-coated microspheres were evaluated. To assess the mucoadhesive properties of this drug delivery system, the percent of mucin adsorption to the surface of coated microspheres was determined. Microspheres were spherical in shape. Encapsulation efficiency of different microsphere formulations varied from 78% to 92%. According to the mucin adsorption results, this particulate system showed suitable mucoadhesive properties. It can be concluded that surface modification of microspheres by chitosan coating would increase the prospects of their usefulness as oral drug delivery systems for CyA.

Pharmacokinetics of oral mycophenolate mofetil in combination with CsA in dogs after nonmyeloablative allogeneic hematopoietic stem cell transplantation

Mycophenolate mofetil (MMF) has been used successfully in solid organ transplantation (SOT) and more recently in nonmyeloablative hematopoietic stem cell transplantation (HSCT) for prophylaxis of graft rejection and acute graft-versus-host disease. However, the pharmacokinetics of MMF seem to differ when applied in HSCT compared to SOT. Here, we analyzed pharmacokinetics of mycophenolic acid (MPA), the active metabolite of MMF, in a nonmyeloablative canine HSCT model. Dogs received nonmyeloablative TBI for conditioning followed by leukocyte antigen-identical littermate HSCT and immunosuppression containing cyclosporin A (CsA) and different doses of MMF. Pharmacokinetics were performed on days 2, 14 and 27. Dose escalation of MMF from 10 to 30 mg/kg tended to increase area under the curve (AUC) and the apparent oral clearance by 45 and 110%, respectively. Doses applied had no linear association with MPA concentration or blood trough level. No significant drug accumulation occurred over time. Using a twice daily MMF regimen, we conclude that an AUC of 30-60 mug/ml h as recommended for SOT cannot be reached in HSCT. Toxicities did not permit single doses higher than 30 mg/kg. Thus, if larger AUCs are desired in order to assure sufficient immunosuppression in HSCT, MMF might have to be administered at least three times daily.

Characterization of a cyclosporine solid dispersion for inhalation

For lung transplant patients, a respirable, inulin-based solid dispersion containing cyclosporine A (CsA) has been developed. The solid dispersions were prepared by spray freeze-drying. The solid dispersion was characterized by water vapor uptake, specific surface area analysis, and particle size analysis. Furthermore, the mode of inclusion of CsA in the dispersion was investigated with Fourier transform infrared spectroscopy. Finally, the dissolution behavior was determined and the aerosol that was formed by the powder was characterized. The powder had large specific surface areas (~ 160 m(2)). The water vapor uptake was dependant linearly on the drug load. The type of solid dispersion was a combination of a solid solution and solid suspension. At a 10% drug load, 55% of the CsA in the powder was in the form of a solid solution and 45% as solid suspension. At 50% drug load, the powder contained 90% of CsA as solid suspension. The powder showed excellent dispersion characteristics as shown by the high emitted fraction (95%), respirable fraction (75%), and fine-particle fraction (50%). The solid dispersions consisted of relatively large (x(50) approximately 7 mum), but low-density particles (rho approximately 0.2 g/cm(3)). The solid dispersions dissolved faster than the physical mixture, and inulin dissolved faster than CsA. The spray freeze-drying with inulin increased the specific surface area and wettability of CsA. In conclusion, the developed powder seems suitable for inhalation in the local treatment of lung transplant patients.

Pharmacokinetic and pharmacodynamic evaluation of cyclosporin A O/W-emulsion and microsphere formulations in rabbits

O/W-emulsion and microspheres containing cyclosporin A (CSA) were prepared to investigate the feasibility of developing new formulations. The pharmacokinetic and pharmacodynamic characteristics of these preparations were evaluated in rabbits and compared to two commercial products, Sandimmun Neoral ® for oral administration and CIPOL Inj. ® for intravenous administration. After oral or intravenous administration (10 mg/kg) to male rabbits, CSA concentration and lymphocyte population in whole blood were measured by TDxFLx ® and Coulter STKS ®, respectively. Total clearance (CL t) was increased after intravenous administration of CSA O/W-emulsion compared with intravenous administration of CIPOL Inj ®. In case of oral administration, AUC and bioavailability of CSA microspheres and O/W-emulsion were not significantly different ( P>0.05) from those of Sandimmun Neoral ®, however, MRT and T max of CSA microspheres and O/W-emulsion were significantly increased ( P<0.05). There were no significant differences in the area between the baseline and effect curves (ABEC) among these formulations ( P>0.05), but the pharmacodynamic availability ( F PD) of CSA O/W-emulsion was 5.51-fold higher than that of CIPOL Inj. ® and was significantly greater than that of Sandimmun Neoral ® ( P<0.05). These results suggest that CSA microspheres and O/W-emulsion have sustained release characteristics and may be used as such formulations for oral or intravenous administration of CSA.

Bioavailability of cyclosporin A dispersed in sodium lauryl sulfate–dextrin based solid microspheres

The purpose of this work was to develop a solid dispersion system containing cyclosporin A (CsA) in order to improve the bioavailability of poorly water-soluble CsA. Solid dispersion systems that are spherical in shape (CsA–microspheres) were prepared with varying ratios of CsA/sodium lauryl sulfate/dextrin using a spray-drying technique. The effects of sodium lauryl sulfate (SLS) and dextrin on the dissolution of CsA dispersed in SLS–dextrin based solid microspheres were investigated. The bioavailability of CsA–microspheres was compared with CsA powder alone and commercial Sandimmun® in dogs. SLS significantly enhanced the dissolution of CsA from microspheres, while dextrin did not affect this. The CsA–microspheres at the CsA/SLS/dextrin ratio of 1/3/1, which gave the highest dissolution rate of CsA among the formula treated, was selected as an optimal formula for oral delivery. This formula gave significantly higher blood levels, area under the drug concentration-time curve (AUC) and maximum blood concentration of drug ( C max) of CsA in dogs compared with the CsA powder alone. The AUC, C max and time to reach maximum blood concentration ( T max) of CsA with CsA–microspheres was not significantly different from those after oral administration of Sandimmun®, suggesting the similar bioavailability to Sandimmun® in dogs. Our study demonstrates that the CsA–microspheres prepared with SLS and dextrin, with improved bioavailability of CsA, would be useful to deliver a poorly water-soluble CsA and could be applicable to other poorly water-soluble drugs.

Synthesis of bioadhesive lectin-HPMA copolymer-cyclosporin conjugates.

An amino group containing cyclosporin A (CsA) derivative has been synthesized and conjugated to N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer via an aromatic azo bond, which can be specifically cleaved by azoreductase activity in colon to release the drug for the treatment of colon diseases. Lectins, peanut (Arachis hypogea) agglutinin (PNA) and wheat germ agglutinin (WGA), have been conjugated to HPMA copolymer-CsA derivative conjugates (PCsA), respectively, to give bioadhesive conjugates. The PNA and WGA are the targeting proteins that can bind to diseased colon tissue and healthy tissue, respectively. There were on average four P(CsA) copolymer chains attached on one WGA molecule with a drug content of 16.0 wt % and five P(CsA) copolymer chains attached on one PNA molecule with a drug content of 11.5 wt %. The incubation of a P(CsA) copolymer with the rat cecal contents resulted in the cleavage of the azo bond and release of the cyclosporin derivative. The biological evaluation of the conjugates is under way.

Oral administration of liposomes containing cyclosporine: a pharmacokinetic study

Liposomal formulation containing cyclosporine A (CSA) were prepared. The most stable liposomes with the composition of CSA, dipalmitoylphosphatidyl choline (DPPC) and cholesterol (Chol.) in molar ratio 1:0.2:1, respectively were administered orally to New Zealand rabbits. The pharmacokinetic of the administered CSA was compared with that of the commercially available oily oral formulation of CSA (Sandimmune) at dose of 15 mg/kg. Cyclosporine concentration in blood was monitored using a radioimmunoassay method (RIA). A change in the pharmacokinetic parameters of CSA due to liposomal encapsulation was observed. A peak concentration was reached in 50 min in case of liposomes compared with 225 min in case of Sandimmune. The rate of absorption ( C max/AUC 0–∞) was significantly faster following the liposome administration. A significant difference in the area under the concentration curve (AUC 0–∞) was found and this was attributed to the difference in the terminal half-lives ( t 1/2 β) which were 8.88±1.94 and 19.3±8.48 h for liposomes and Sandimmune preparations, respectively. The mean residence time (MRT) and the mean absorption time (MAT) were dramatically decreased following the administration of liposomal formulation. Generally, there was less inter-individual variation in the values of rate of absorption, t 1/2 β and MRT when CSA liposomes were orally administered compared to the administration of Sandimmune. Thus, an oral liposomal formulation for CSA can be developed to offer the advantages of low variability and fast onset of action.

Lymphotropic delivery of cyclosporin A by intramuscular injection of biodegradable microspheres in mice.

Biodegradable microspheres containing cyclosporin A (CsA), an immunosuppressant, enabled the lymphotropic delivery of the drug over the long term by parenteral administration in mice. The CsA encapsulated in the microspheres of polylactic acid polymer (Mw, 9000) was released over 30 days in vitro. The intramuscular injection of the microspheres containing CsA in the femoral site of mice maintained the drug at a high level in the inguinal lymph nodes over 1 month, although only low blood levels of the drug were observed.

Liposomes as carriers of cyclosporin A

Liposomes prepared from 1,2-dimyristoyl-sn-3-phosphatidylglycerol (DMPG) and 1,2-dimyristoyl-sn-3-phosphatidylcholine (DMPC) containing cyclosporin A (CsA) were reviewed in respect of the amount and localization of associated CsA. It was found that DMPG liposomes are capable of binding a much higher amount of CsA than those prepared from DMPC. Furthermore, while CsA associated with DMPG was embedded within the hydrophobic region of phospholipids, CsA associated with DMPC was excluded from the hydrophobic region and was entrapped in the hydrophilic region of these liposomes.

Interaction of cyclosporin A with 1,2-dimyristoyl- sn-glycero-3-phosphocholine unilamellar vesicles studied by electron spin resonance

Thermally induced changes of unilamellar 1,2-dimyristoyl- sn-glycero-3-phosphocholine (DMPC) liposomes and DMPC liposomes containing cyclosporin A (CsA) were studied by electron spin resonance (ESR) spectroscopy with 5-, 12-, or 16-nitroxide stearic acid (NO-SA) as probes. All liposomes were purified by Sepharose 4B column chromatography and the amount of CsA associated with these liposomes was determined. The results obtained established that the temperature range of the gel-to-liquid crystalline phase transition of liposomes does not broaden significantly in the presence of CsA. In addition, the order of parameters of these liposomes obtained with 5-NO-SA as a probe showed no significant influence of CsA. It was concluded that CsA does not interact with the hydrocarbon region of DMPC liposomes but resides exclusively within the aqueous compartment of liposomes.