Current Drug Delivery - Volume 15, Issue 8, 2018

Background: Transdermal route of delivery of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) has several advantages over other routes like reduced adverse effects, less systemic absorption, and avoidance of first-pass effect and degradation in the gastrointestinal tract (GIT). Transdermal route is also beneficial for drugs having a narrow therapeutic index. The skin acts as the primary barrier for transdermal delivery of various therapeutic molecules. Various advanced nanocarrier systems offer several advantages like improved dermal penetration along with an extended drug release profile due to their smaller size and high surface area. Various nanocarriers explored for transdermal delivery of NSAIDs are liposomes, niosomes, ethosomes, polymeric nanoparticles (NPs), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), dendrimers, nanosuspensions/nanoemulsion, and nanofibers. Objectives: In the present review, our major aim was to explore the therapeutic potential of advanced nanocarrier systems enlisted above for transdermal delivery of NSAIDs. All literature search regarding advanced nanocarrier systems for transdermal delivery of NSAIDs was done using Google Scholar and Pubmed. Conclusions: Advanced nanocarriers have shown various advantages like reduced side effect, low dosing frequency, high skin permeation, and ease of application over conventional transdermal delivery systems of NSAIDs in various preclinical studies. However, clinical exploration of advanced nanocarrier systems for transdermal delivery of NSAIDs is still a challenge.

Androgenetic alopecia, generally recognized as male pattern baldness, is a gradually developing medical and physiological change, which is manifested by continuous hair-loss from scalp. Finasteride (4-aza-3-oxosteroid) is a potent anti-baldness compound that selectively and competitively inhibits the 5α-reductase isoenzymes. Prolonged oral use of finasteride leads to the emergence of sexual disorders including decrease in libido, gynecomastia, erectile dysfunction, ejaculation disorder, orgasm disorders and mood disturbances. Since, hair follicles widely home in 5α-reductase, topical formulations of finasteride in comparison to its oral formulations are expected to potentially reduce its systemic adverse effects. The analysis of literature has revealed some delivery systems developed for the enhanced and localized penetration of finasteride into the skin. These finasteride delivery systems include polymersomes, vesicular nanocarriers, vesicular ethosomal carriers, liposomes and niosomes, liquid crystalline nanoparticles, topical solutions and gels. The aim of this review article is to briefly amass all literature on topical delivery of finasteride to elaborate best dosage form, i.e. formulation having maximum permeation rate. This study will serve as a future perspective regarding topical delivery of finasteride. The literature analysis has exhibited that most of the previous investigators have used propylene glycol in their finasteride-loaded topical formulations, while poloxamer P407, monoolein, transcutol P and choline was used in few formulations. Moreover, among all drug delivery systems, finasteride liposomal gel system consisting of 2% methyl cellulose and gel system containing poloxamer P407 exhibited the highest flux with a value of 28.4 ± 1.3 μg/cm2h and 23.1 ± 1.4 μg/cm2h, respectively. Several topical drug delivery techniques such as topical microneedles, aerosol foams, nanoemulsions, microsponges, and emulsifier free formulations, fullerenes, ointments, pastes, creams, gel and lotions are still to be worthy regarding finasteride topical delivery in future.

Background: Bladder cancer is the second type of malignant carcinoma of the urinary tract. The treatment is time-consuming and requires maintenance doses of the drug for long period of time with important side effects. Curcumin has shown evident clinical advances in the treatment of cancer. The technology of microencapsulation and the use of mucoadhesive materials can contribute to modify the delivery and improve the bioavailability of curcumin. Objective: The aim of this study was to design and characterize mucoadhesive microparticles containing curcumin using multivariate analysis and the spray-drying technique. Methods: A factorial design 32+1 was employed to investigate the influence of gelatin, ethylcellulose, and curcumin on size, polydispersity index, drug content and entrapment efficiency. Microparticles were also evaluated by ATR-FTIR, X-ray diffraction, antioxidant activity, in-vitro release profile, exvivo mucoadhesion performance, and in-vitro cytotoxicity. Results: Microparticles showed non-uniform surface, mean diameter from 2.73 μm to 4.62 μm and polydispersity index from 0.72 to 1.09, according to the different combinations of the independent factors. These independent variables also had a significant effect on the drug content. The highest values of drug trapping efficiency were obtained with the highest concentration of curcumin and polymers. Formulations displayed slow drug release and important antioxidant activity. The good mucoadhesive performance of microparticles was assessed by the falling film technique. Moreover, the formulations did not display in vitro toxicity against Artemia salina and Fibroblasts LM(TK). Conclusion: The design results were useful for developing of curcumin dosage form with good physicochemical characteristics and mucoadhesive properties for the bladder administration.

Background: Taxifolin (TAX) is a flavonoid that has numerous pharmacological properties, including an antioxidant ability superior to that of other flavonoids due to its particular structure. Nevertheless, it has low oral bioavailability, which limits its therapeutic application. In this context, potentially important approaches for systemic drug delivery could be by alternative routes such as skin and vaginal mucosa, once both routes have a variety of advantages compared with the oral route, including the ability to bypass both first-pass hepatic metabolism and the consequent degradation in the gastrointestinal tract. Vaginal delivery could also account for a local effect, or an effect on circumvent microregion. Objective: The major objective of this study was to develop and validate a high-performance liquid chromatography (HPLC) method for the determination of TAX in a semisolid dosage forms and then to evaluate ex vivo permeations across porcine vaginal mucosa and human skin. Methods: TAX was incorporated into an oil-in-water emulsion developed previously by our group. Method for quantification was developed and validated using HPLC. Permeation through human skin and vaginal porcine mucosa were conducted in Franz-type cells. Results: The method was precise (CV < 5%), accurate (recovery between 98% and 102%), linear (R2> 0.99), specific, and robust. Permeation experiments through porcine vaginal mucosa and human skin presented permeated percentages equal to 87.43% and 48.09% (per dose), respectively. Conclusion: The results suggest that, in the matrixes studied, TAX may be able to exert its biological activities systemically when applied by these routes. Furthermore, it exhibits greater permeability potential when administered by intravaginal route.

Background: Vinorelbine bitartrate (VRL), a semi synthetic vinca alkaloid approved for breast cancer, has been proven to be beneficial as first line and subsequent therapies. However, its hydrophilic and thermo labile nature provides hindrance to oral clinical translation. Objectives: The current work focused on the application of DOE a modern statistical optimization tool for the development and optimization of a solid lipid nanoparticle (SLN) formulation that can encapsulate hydrophilic and thermolabile Vinorelbine bitartrate (VRL) to a maximum extent without compromising integrity and anticancer activity of the drug. Methods: SLNs were prepared by solvent diffusion technique employing Taguchi orthogonal array design with optimized formulation and process variables. The emulsifying nature and low melting point of glyceryl mono-oleate (GMO) were exploited to enhance entrapment and minimizing temperature associated degradation, respectively. Moreover, two types of surfactants, Vitamin E TPGS (TPGS) and Poloxamer-188 were utilized to obtain TPGS-VRL-SLNs and PL-VRL-SLNs, respectively. The SLNs were characterized for various physicochemical properties, in-vitro drug release kinetics and anticancer activity by MTT assay on MCF-7 cancer cell lines. Results: The SLNs were found to be spherical in shape with entrapment efficiency (EE) up to 58 %. Invitro release studies showed biphasic release pattern following Korsemeyer peppas model with fickian release kinetics. Results of MTT assay revealed that TPGS-VRL-SLNs and PL-VRL-SLNs were 39.5 and 18.5 fold more effective, respectively, compared to the pristine VRL. Conclusion: DOE approach was successfully applied for the development of VRL-SLNs. Enhanced entrapment and anticancer efficacy of TPGS-VRL-SLN can be attributed to emulsifying nature of GMO and inherent cytotoxic nature of TPGS, respectively, which synergizes with VRL. Therefore, TPGS associated SLNs may be potential carrier in cancer chemotherapeutics.

Objectives: In this study, central composite factorial design was used for the preparation and optimization of chitosan/Na-alginate hydrogel films containing metformin via solvent evaporation technique. Methods: Low and high molecular weight (MW) chitosan was used as a polymer in different concentrations while genipin was used as a crosslinking agent. Drug release studies were performed in simulated gastric and intestinal fluids at pH 1.2 and 7.4 of formulated hydrogels. Results: For low MW chitosan hydrogel, the highest drug release at pH 1.2 was observed i.e., 9.82% for 2 hrs while at pH 7.4, 95.52% drug release was observed after 12 hrs. In case of high MW chitosan hydrogel 9.67% drug release at ph1.2 for 2 hrs and 90.63% drug release at pH 7.4 after 12 hrs was observed. The highest T50% of low MW and high MW chitosan hydrogel was observed as 22.72 and 33.34 hrs, respectively, while the highest dynamic swelling was observed as 8.21 and 7.9, respectively. Conclusion: It was found that by changing the ratios of polymers as well as crosslinking agent, the release rate of metformin can be modified. Low MW chitosan hydrogel showed an increased release rate than high MW chitosan hydrogel and by increasing the concentration of crosslinking agent, the release rate was found to be decreased and vice versa.

Objectives: The effect of magnesium sulfate on brain tissue of SD rats irradiated by 6MeV electron was investigated. Methods: SD rats were divided into three groups: control group, irradiation (IR group) and irradiation treated with magnesium sulfate (IR+M group). After being anesthetized, the whole brains of IR group and IR+M group were exposed to 6 MeV electron radiation. IR+M group was i.p. injected with 10% magnesium sulfate (400 mg/kg) one day before radiation and three days and five days after radiation. And on the 1st, 3rd, 7th and 14th day after radiation, SD rats were euthanatized to take brain tissue for the detection of calcium, redox status and cell apoptosis, as well as the expression of NF-ΚB and ICAM-1. Results: The results indicated that magnesium treatment may alleviate the elevation of calcium and enhance redox status through increasing the activities of superoxide dimutase (SOD) and myeloperodase (MPO), and decreasing the concentration of malondialdehyde (MDA). Tunnel and immunohistochemistry assay suggested that treatment with magnesium decreased the apoptosis rate of brain cells and the expressions of caspase-3, respectively. Decline of the expression of NF-ΚB and ICAM-1 protein was observed after the treatment of magnesium. Conclusion: All the results demonstrated that magnesium may elicit protective effect against radiationinduced brain injury by reducing calcium overload, improving redox and inhibiting cell apoptosis. Moreover, magnesium significantly down-regulated the protein or mRNA levels of NF-ΚB and ICAM- 1. The findings may provide references for the application of magnesium in clinic for brain injury induced by radiation.

Background: Since their appearance on the drugs of abuse market, synthetic cannabinoids (SCs) are gaining increasing toxicological relevance. They are consumed without knowledge of their toxicokinetic (TK) and toxicodynamic properties and human studies are not allowed due to ethical reasons. A controlled animal TK study following nebulization of 4-ethylnaphthalene-1-yl-(1-pentylindole- 3-yl)methanone (JWH-210), 2-(4-methoxyphenyl)-1-(1-pentyl-indole-3-yl)methanone (RCS-4) as well as Δ9-tetrahydrocannabinol (THC) to pigs should be helpful for better interpretation of analytical results in cases of misuse or poisoning. As a prerequisite, an in-vitro test system mimicking a ventilated pig had to be developed to determine the quantity and reproducibility of which drug dose is delivered to the pig lung. Methods: JWH-210, RCS-4, and THC (1 mg in 2 mL ethanol each) were nebulized during ventilation using an ultrasonic nebulizer. The drug aerosol was delivered via the inspiratory limb and the endotracheal tube passing through a glass fiber filter (n = 6). The drugs were extracted from the filters using ethanol and ultrasonication. After several dilution steps and adding an internal standard solution, the extracts were analyzed by LC-MS/MS. Results: Extraction of the nebulized drugs revealed delivery efficiencies of 78.8 ± 5.0% for JWH-210, 70.5 ± 6.9% for RCS-4, and 70.8 ± 7.9% for THC. The loss of about 20-30% of the administered dose might be attributable to retention in the nebulizer device or adhesion of the aerosol particles to the tube wall. Conclusion: Nevertheless, regarding delivery efficiencies, the minor standard deviations indicate an acceptable reproducibility, suggesting that this administration system is suitable for application in TK studies.

Background: Wound healing is a biological process that can get in a state of pathologic inflammation, requiring the use of specific medications able to promote proper tissue repair. Objective: The study describes the production and characterization of nanoparticle based gel for wound healing treatment designed to deliver hyaluronic acid and retinyl palmitate onto the skin. Methods: Tristearin solid lipid nanoparticles and nanostructured lipid carriers based on a tristearin and caprylic/capric triglyceride mixture were produced and characterized. Gel spreadability and viscosity were investigated. Drug diffusion and “in vitro” wound healing were assessed by Franz cell and scratch wound assay in keratinocytes. Results: Cryogenic transmission electron microscopy evidenced flat discoid nanoparticles. Photon correlation spectroscopy analysis indicated homogeneous dimensional distribution and mean diameter 132±46 nm. X-ray evidenced a lamellar inner structure of lipid nanoparticles. Nanostructured lipid carriers, being based on a heterogeneous solid/ liquid lipid mixture, could better solubilize retinyl palmitate and control its stability. The hyaluronic acid directly added into nanoparticles' dispersion enabled to obtain a shear-thinning gel suitable for cutaneous administration. Retynil palmitate diffusion was slower from the nanoparticulate gel with respect to the plain nanoparticle dispersion. The “wound healing” effect of nanoparticulate gel containing retinyl palmitate and hyaluronic acid, analyzed in HaCaT cells, showed significant differences in wounded areas between treated and control cells during the first 24 h postwounding suggesting a synergic effect of retinyl palmitate and hyaluronic acid in “in vitro” wound healing. Conclusions: This study suggests that a nanoparticle based hyaluronate gel containing retinyl palmitate can be efficiently used for wound healing.

Background: Malaria continues to be a major health concern and affects more than 200 million people a year. Drugs currently used for treatment of malaria are increasingly rendered ineffectual by the ongoing emergence of parasite resistance. For any new drugs, however, knowledge of their membrane permeability is an essential pre-requisite for eventual use. Treatment failure and emergence of resistance can occur as a result of reduced availability of the drug at the desired site of action. Cellbased permeability assays such as Caco-2 cell monolayers serve as a model for predicting drug absorption and efflux, and provide an estimate of drug bioavailability. Objective: Here we have studied the bi-directional transport of new anti-malarial compounds, artemisone and artemiside, as well as reference compounds, namely the known anti-malarial drug artemether, and caffeine and atenolol. Methods: The Caco-2 cell monolayer model was used to assess the membrane permeation properties of these compounds, and to identify if they are subject to P-gp associated efflux, in the presence and absence of verapamil. The effect of piperine on the transport of the compounds that were identified to be P-gp substrates was also assessed. Samples withdrawn from the acceptor chambers at pre-determined time intervals were analysed by means of high-performance liquid chromatography (HPLC). Results: Transport results in terms of the absorptive direction revealed that artemisone and artemether had low absorption rates relative to the reference compounds. It was further demonstrated that artemisone is slightly effluxed, and although both artemether and artemiside were susceptible to P-gp mediated efflux, it appears that other efflux proteins may also be involved. Conclusion: The low permeability of anti-malarial drugs must be borne in mind during development of effective dosage regimens of new drugs.

Objective: Formulation of injectable In situ forming implant (ISI) systems of lornoxicam for dental and postoperative pain management to decrease dosing frequency and increase patient compliance. Methods: Polymeric in situ implant solutions were prepared using different concentrations and inherent viscosities of Poly-DL-lactide (PDL) or DL-lactide/glycolide copolymer (PDLG) using 22X4 factorial experimental design. Nonpolymeric systems were prepared using different concentrations of lipids like cetyl alcohol and stearyl alcohol and also sucrose acetate isobutyrate (SAIB) using 32 factorial experimental design. In vitro release study, rheological measurement, syringeability assessment and effect of γ-sterilization were used for evaluation of the prepared formulae. In vivo pharmacokinetic study of lornoxicam from the most optimum formula was conducted in a rabbit model using HPLC analysis of blood samples. Results: Polymeric systems showed high burst release followed by very slow release rate over 72 hours. Formula I 24 (containing SAIB 80% (w/w)) showed relatively low burst release followed by diffusion controlled release pattern, low viscosity, Newtonian flow behavior and good syringeability. γ- sterilization had no significant effect on the in vitro release and the physical nature of the most optimum formula. In vivo study concluded that intramuscularly injected In situ implant formula I 24 showed prolonged release pattern compared to the marketed product which was indicated by the increased Tmax and the extended mean residence time. Conclusion: Lornoxicam ISI systems could be promising as convenient injectable sustained release delivery systems for dental and postoperative pain management.

Objective: The incredibly serious problem of Hepatitis B is virus-related chronic liver disease. The conventional preventive treatment of Hepatitis B requires booster dose, which requires repeated administration of the vaccine to the subject. Thus, there is a need to develop a formulation which can eliminate the need of frequent dosing and enhance patient's acquiescence. To prepare single dose nanovaccine of HBsAg by utilizing central composite design for optimization and interaction of independent variables effects on measured response. Methods: Nanovaccines were characterized for particle size, morphology, integrity, internalization, proliferation response and haemocompatibility. Nanoparticles at single and multiple doses were compared with booster dose of alum-HBsAg vaccine and measure the immunological marker and cytokine (interleukin-2 and interferon-Y) levels by ELISA techniques in BALB/c mice. Results: The designed nanoparticles were found to have nanometric size, high entrapment efficiency and retained antigen integrity. Nanoparticles showed maximum proliferation and efficiently internalized by lymph and spleen cell without eliciting significant toxicity and haemocampatible. Conclusion: The comparable data of anti-HBsAg titre between nanovaccine and alum adsorbed HBsAg demonstrated that single dose of nanoparticles is sufficient for production of immunoglobulin plus cytokine levels, maintain immunogenicity at longer period of time and eliminate the booster dose. Nanovaccines trigger immune responses and showing adjuvant properties.