Understanding the Different Effects of Inhaler Design on the Aerosol Performance of Drug-Only and Carrier-Based DPI Formulations. Part 1: Grid Structure

The design of a dry powder inhaler device has significant influence on aerosol performance; however, such influence may be different between the drug-only and carrier-based formulations. The present study aims to examine the potential difference on the dispersion between these distinct types of formulations, using Aerolizer^® as a model inhaler with the original or modified (cross-grid) designs. A coupled CFD-discrete element method analysis was employed to determine the flow characteristics and particle impaction. Micronized salbutamol sulphate as a drug-only formulation and three lactose carrier-based formulations with various drug-to-carrier weight ratios 1:5, 1:10 and 1:100 were used. The in vitro aerosolization performance was assessed by a next-generation impactor operating at 100 L/min. Using the original device, FPF_loaded was reduced from 47.5?±?3.8% for the drug-only formulation to 31.8?±?0.7%, 32.1?±?0.7% and 12.9?±?1.0% for the 1:5, 1:10 and 1:100 formulations, respectively. With the cross-grid design, powder-mouthpiece impaction was increased, which caused not only powder deagglomeration but also significant drug retention (doubling or more) in the mouthpiece, and the net result is a significant decrease in FPF_loaded to 36.8?±?1.2%, 20.9?±?2.6% and 21.9?±?1.5% for the drug-only, 1:5 and 1:10 formulations, respectively. In contrast, the FPF_loaded of the 1:100 formulation remained the same at 12.1?±?1.3%, indicating the increased mouthpiece drug retention was compensated by increased drug detachment from carriers caused by increased powder-mouthpiece impaction. In conclusion, this study has elucidated different effects and the mechanism on the aerosolization of varied dry powder inhaler formulations due to the grid design.     

Production of Inhalation Phage Powders Using Spray Freeze Drying and Spray Drying Techniques for Treatment of Respiratory Infections

Purpose

The potential of aerosol phage therapy for treating lung infections has been demonstrated in animal models and clinical studies. This work compared the performance of two dry powder formation techniques, spray freeze drying (SFD) and spray drying (SD), in producing inhalable phage powders.

Method

A Pseudomonas podoviridae phage, PEV2, was incorporated into multi-component formulation systems consisting of trehalose, mannitol and L-leucine (F1?=?60:20:20 and F2?=?40:40:20). The phage titer loss after the SFD and SD processes and in vitro aerosol performance of the produced powders were assessed.

Results

A significant titer loss (~2 log) was noted for droplet generation using an ultrasonic nozzle employed in the SFD method, but the conventional two-fluid nozzle used in the SD method was less destructive for the phage (~0.75 log loss). The phage were more vulnerable during the evaporative drying process (~0.75 log further loss) compared with the freeze drying step, which caused negligible phage loss. In vitro aerosol performance showed that the SFD powders (~80% phage recovery) provided better phage protection than the SD powders (~20% phage recovery) during the aerosolization process. Despite this, higher total lung doses were obtained for the SD formulations (SD-F1?=?13.1?±?1.7?×?10⁴ pfu and SD-F2?=?11.0?±?1.4?×?10⁴ pfu) than from their counterpart SFD formulations (SFD-F1?=?8.3?±?1.8?×?10⁴ pfu and SFD-F2?=?2.1?±?0.3?×?10⁴ pfu).

Conclusion

Overall, the SD method caused less phage reduction during the powder formation process and the resulted powders achieved better aerosol performance for PEV2.

     

A Rifapentine-Containing Inhaled Triple Antibiotic Formulation for Rapid Treatment of Tubercular Infection

Purpose

The potential for rifapentine-containing oral therapeutic regimens to significantly shorten the current six-month anti-tubercular treatment regimen is confounded by high plasma protein binding of rifapentine. Inhaled aerosol delivery of rifapentine, a more potent anti-tubercular antibiotic drug, in combination with other first-line antibiotics may overcome this limitation to deliver a high drug dose at the pulmonary site of infection.

Methods

A formulation consisting of rifapentine, moxifloxacin and pyrazinamide, with and without leucine, was prepared by spray-drying. This formulation was assessed for its physico-chemical properties, in vitro aerosol performance and antimicrobial activity.

Results

The antibiotic powders, with and without leucine, had similar median aerodynamic diameters of 2.58?±?0.08 μm and 2.51?±?0.06 μm, with a relatively high fine particle fraction of 55.5?±?1.9% and 63.6?±?2.0%, respectively. Although the powders were mostly amorphous, some crystalline peaks associated with the δ polymorph for the spray-dried crystalline pyrazinamide were identified.

Conclusions

Stabilisation of the powder with 10% w/w leucine and protection from moisture ingress was found to be necessary to prevent overt crystallisation of pyrazinamide after long-term storage. In vitro biological assays indicated antimicrobial activity was retained after spray-drying. Murine pharmacokinetic studies are currently underway.     

Cyclodextrin-based nanosponges: effective nanocarrier for Tamoxifen delivery

The purpose of the present study was to develop Tamoxifen loaded β-cyclodextrin nanosponges for oral drug delivery. The three types of Tamoxifen loaded β-cyclodextrin nanosponges were synthesized by varying the molar ratios of β-cyclodextrin to carbonyldiimidazole as a crosslinker viz. 1:2, 1:4 and 1:8. The Tamoxifen nanosponge complex (TNC) with particle size of 400–600?nm was obtained by freeze drying method. Differential scanning calorimetry, Fourier transformed infra-red spectroscopy and X-ray powder diffraction studies confirmed the complexation of Tamoxifen with cyclodextrin nanosponge. AUC and C_max of TNC formulation (1236.4?±?16.12 µg·mL^?1 h, 421.156?±?0.91 µg/mL) after gastric intubation were 1.44 fold and 1.38 fold higher than plain drug (856.079?±?15.18 µg·mL^?1 h, 298.532?±?1.15 µg/mL). Cytotoxic studies on MCF-7 cells showed that TNC formulation was more cytotoxic than plain Tamoxifen after 24 and 48?h of incubation.     

Aerosol Delivery of Nanoparticles in Uniform Mannitol Carriers Formulated by Ultrasonic Spray Freeze Drying

Purpose

While most examples of nanoparticle therapeutics have involved parenteral or IV administration, pulmonary delivery is an attractive alternative, especially to target and treat local infections and diseases of the lungs. We describe a successful dry powder formulation which is capable of delivering nanoparticles to the lungs with good aerosolization properties, high loadings of nanoparticles, and limited irreversible aggregation.

Methods

Aerosolizable mannitol carrier particles that encapsulate nanoparticles with dense PEG coatings were prepared by a combination of ultrasonic atomization and spray freeze drying. This process was contrasted to particle formation by conventional spray drying.

Results

Spray freeze drying a solution of nanoparticles and mannitol (2 wt% solids) resulted in particles with an average diameter of 21?±?1.7 μm, regardless of the fraction of nanoparticles loaded (0–50% of total solids). Spray freeze dried (SFD) powders with a 50% nanoparticle loading had a fine particle fraction (FPF) of 60%. After formulation in a mannitol matrix, nanoparticles redispersed in water to < 1 μm with hand agitation and to < 250 nm with the aid of sonication. Powder production by spray drying was less successful, with low powder yields and extensive, irreversible aggregation of nanoparticles evident upon rehydration.

Conclusions

This study reveals the unique advantages of processing by ultrasonic spray freeze drying to produce aerosol dry powders with controlled properties for the delivery of therapeutic nanoparticles to the lungs.     

Preparation and characterization of spray dried inhalable powders containing chitosan nanoparticles for pulmonary delivery of isoniazid

The aim of this study was to prepare spray dried inhalable powders containing isoniazid-loaded chitosan/tripolyphosphate (TPP) nanoparticles for sustained delivery of the drug to the lung. Nanoparticles were prepared by ionic gelation method. In-vitro drug release study indicated that the rate of drug release from nanoparticles was decreased by increasing the amount of chitosan. Entrapment of isoniazid into chitosan/TPP nanoparticles decreased minimum inhibitory concentrations (MIC) of the drug against mycobacterium avium intracellulare. Nanoparticles were spray dried using excipients such as lactose, mannitol and maltodextrin alone or with leucine. Results showed that the obtained powders had different aerosolization property. It was observed that by adding leucine, the particle size of microparticles deceased and the process yield and fine particle fraction (FPF) increased significantly. The in-vitro deposition data indicated that spray drying of isoniazid-loaded nanoparticles with lactose in the presence of leucine resulted in the production of inhalable powders with the highest FPF (45%).     

Mucoadhesive buccal film containing ornidazole and dexamethasone for oral ulcers: in vitro and in vivo studies

A bilayered mucoadhesive buccal film containing a combination of ornidazole (OD) and dexamethasone sodium phosphate (DEX) was prepared using solvent casting to treat oral ulcers. Films were systematically evaluated in vitro to obtain the optimum formulation. The therapeutic effects of these films were investigated in the rabbit oral ulcer model and the in vivo release of OD and DEX in the human oral cavity was also evaluated. The backing layer contained ethyl cellulose and an optimal mucoadhesive layer containing both OD and DEX was produced. Films from the optimum formulation were 0.427?±?0.015?mm thick, weighed 55.89?±?0.79?mg, and had a surface pH of 6.34?±?0.01. The drug content of the optimum formulation approximated the theoretical value with good uniformity (2.959?±?0.106?mg/cm² for OD and 0.877?±?0.031?mg/cm² for DEX). The formulation showed favorable swelling characteristics and both drugs were released at >95% after 4?h. Moreover, the compound film had a statistically significant effect on mucosal repair and reduced ulcer inflammation without stimulating the human oral mucosa. C_max of OD in saliva was 37.04?μg/ml and that of DEX was 9.737?μg/ml. Given promising therapeutic effects, the compound film developed here could become a local drug delivery device for treating oral ulcers.     

Investigation of true nanoemulsions for transdermal potential of indomethacin: characterization,rheological characteristics,and ex vivo skin permeation studies

The aim of the present study was to investigate the potential of true nanoemulsions for transdermal delivery of indomethacin. Thermodynamically stable true nanoemulsions were characterized for morphology using transmission electron microscopy (TEM), droplet size, rheological characteristics, and refractive index. The rheological behavior for all true nanoemulsions was found to be Newtonian as viscosity was unchanged by increasing the rate of shear. The ex vivo skin permeation studies were performed using Franz diffusion cell with rat skin as permeation membrane. The ex vivo skin permeation profile of optimized formulation was compared with marketed Indobene gel and nanoemulsion gel. Significant increase in permeability parameters was observed in nanoemulsion formulations (P?<?0.05). The steady-state flux (J_ss) and permeability coefficient (K_p) for optimized nanoemulsion formulation were found to be 73.96?±?2.89?μg/cm²/h and 1.479?×?10^?2?±?0.289?×?10^??2?cm/h, respectively, which were significant compared with Indobene gel and nanoemulsion gel (P?<?0.05). Enhancement ratio (E_r) was found to be 7.88 in optimized formulation F6 compared with other formulations. These results suggested that nanoemulsions can be used as potential vehicles for improved transdermal delivery of indomethacin.     

Chemoprevention of skin cancer using low HLB surfactant nanoemulsion of 5-fluorouracil: a preliminary study

Abstract

Oral delivery of 5-fluorouracil (5-FU) is difficult due to its serious adverse effects and extremely low bioavailability. Therefore, the aim of present investigation was to develop and evaluate low HLB surfactant nanoemulsion of 5-FU for topical chemoprevention of skin cancer. Low HLB surfactant nanoemulsions were prepared by oil phase titration method. Thermodynamically stable nanoemulsions were characterized in terms of droplet size distribution, zeta potential, viscosity and refractive index. Selected formulations and control were subjected to in vitro skin permeation studies through rat skin using Franz diffusion cells. Optimized formulation F9 was subjected to stability and in vitro cytotoxic studies on melanoma cell lines. Enhancement ratio was found to be 22.33 in formulation F9 compared with control and other formulations. The values of steady state flux and permeability coefficient for formulation F9 were found to be 206.40?±?14.56?µg?cm^?2?h^?1 and 2.064?×?10^?2?±?0.050?×?10^?2?cm?h^?1, respectively. Optimized formulation F9 was found to be physical stable. In vitro cytotoxicity studies on SK-MEL-5 cancer cells indicated that 5-FU in optimized nanoemulsion is much more efficacious than free 5-FU. From these results, it can be concluded that the developed nanoemulsion might be a promising vehicle for chemoprevention of skin cancer.     

Nanosizing of valsartan by high pressure homogenization to produce dissolution enhanced nanosuspension: pharmacokinetics and pharmacodyanamic study

Purpose: The purpose of the present study was to formulate and evaluate nanosuspension of Valsartan (VAL), a poorly water soluble and low bioavailable drug (solubility of 0.18?mg?mL^?1; 23% of oral bioavailability) with the aim of improving the aqueous solubility thus the bioavailability and consequently better anti-hypertensive activity.

Methods: Valsartan nanosuspension (VAL-NS) was prepared using high-pressure homogenization followed by lyophilisation. The screening of homogenization factors influencing nanosuspension was done by 3-factorial, 3-level Box-Behnken statistical design. Model suggested the influential role of homogenization pressure and cycles on drug nanosizing. The optimized formulation containing Poloxamer^?188 (PXM 188) was homogenized for 2 cycles at 500 and 1000?bar, followed by 5 cycles at 1500 bars.

Results: The size analysis and transmission electron microscopy showed nanometric size range and uniform shape of the nanosuspension. The in vitro dissolution showed an enhanced release of VAL from nanosuspension (VAL-NS) compared to physical mixture with PXM 188. Pharmacodynamic results showed that, oral administration of VAL-NS significantly lowered (p?≤?0.001) blood pressure in comparison to non-homogenized VAL (VAL-Susp) in Wistar rat. The level of VAL in rat plasma treated with VAL-NS showed significant difference (p?≤?0.005) in C_max (1627.47?±?112.05?ng?mL^?1), T_max (2.00?h) and AUC_0→24 (13279.2?±?589.426?ng?h?mL^?1) compared to VAL-Susp that was found to be 1384.73?±?98.76?ng?mL^?1, 3.00?h and 9416.24?±?218.48?ng?h?mL^?1 respectively. The lower T_max value, proved the enhanced dissolution rate of VAL.

Conclusion: The overall results proved that newly developed VAL-NS increased the plasma bioavailability and pharmacodyanamic potential over the reference formulation containing crude VAL.     

Delivery of atovaquone and proguanil across sublingual membranes,in vitro

Malarone^?, a combination of atovaquone (AT) and proguanil (PR), is indicated for the prophylaxis and treatment of uncomplicated Plasmodium falciparum malaria. This study aimed to determine in vitro the feasibility of delivering the combination of AT and PR as a spray formulation via the sublingual route, using Franz diffusion cells incorporating porcine sublingual mucosa. Firstly, 1?mg mL^?1 of each drug in 20% 1,8-Cineole in ethanol was used; and secondly, 5?mg mL^?1 AT and 1?mg mL^?1 PR in 20% 1-methyl-2-pyrrolidone in ethanol was examined, dosed every 2?h over a 12-h period and receptor phase samples were analyzed by HPLC. From the first study, mean fluxes for AT and PR were 12.89?±?1.2 and 5.88?±?0.9 µg cm^?2 h^?1 respectively; pharmacokinetic calculations indicated that these fluxes were insufficient to achieve the target plasma concentrations for AT and PR of 1.4 µg mL^?1 and 200?ng mL^?1 respectively, in the treatment of falciparum malaria. However, in the second study, the fluxes of AT and PR increased to 50.92?±?20.8 and 12.01?±?1.5 µg cm^?2 h^?1 respectively, and pharmacokinetic calculations indicated that therapeutic plasma concentrations are attainable for pediatric application.     

Mineral pitch stimulates humoral,cellular and innate immune responses in mice

Abstract

Context: Mineral pitch (MP), a traditional medicine, is proposed to boost immunity in conditions that suppress Th1 cytokines such as AIDS/HIV, tuberculosis, leishmaniasis and cancer.

Objective: This study investigates the immunoregulatory mechanisms of MP in innate, humoral and cell-mediated immunity.

Materials and methods: Mice given MP (100, 200, 300 or 400?mg/kg, orally) for 10 consecutive days were immunized intravenously with goat RBC or ovalbumin, and investigated for plaque-forming cells (PFC), hemagglutination titer, hypersensitivity response, lymphocyte proliferation and macrophage function.

Results: MP increased PFC (330.2 versus 182.2/10⁶ splenocytes) in mice immunized with goat RBC and elicited ovalbumin-specific IgG titer at 400?mg/kg. Increase in Th1 immunity was correlated with the increased level of IFN-γ (724 versus 470?pg/ml) and decreased IL-4 (96 versus 178?pg/ml). CD4⁺/CD3⁺ ratio and delayed-type hypersensitivity response also increased to, respectively, 20.62?±?0.59 (versus 16.47?±?0.72) and 1.59?±?0.12 (versus 0.87?±?0.10?mm) in MP-treated mice. MP increased lymphocyte proliferation (11.14?±?0.60 versus 5.81?±?0.40 SI) and macrophage phagocyte response (0.24?±?0.02 versus 0.15?±?0.009), expressed as absorbance at 570?nm, but decreased nitrite production (17.4?±?1.10 versus 24.3?±?1.30?µM/10⁶ cells). We also observed an increased bone marrow cellularity (24.5?±?1.10 versus 17.10?±?0.70 cells/femur) and WBC count (12?667?±?377 versus 9178?±?213 cells/mm³) following MP treatment. There was no sign of toxicity at 400?mg/kg, 1/12th of reported LD₅₀.

Conclusion: MP elicits a dose-dependent Th1 immune response.     

Controlled delivery of ropinirole hydrochloride through skin using modulated iontophoresis and microneedles

Abstract

The objective of this study was to investigate the effect of modulated current application using iontophoresis- and microneedle-mediated delivery on transdermal permeation of ropinirole hydrochloride. AdminPatch® microneedles and microchannels formed by them were characterized by scanning electron microscopy, dye staining and confocal microscopy. In vitro permeation studies were carried out using Franz diffusion cells, and skin extraction was used to quantify drug in underlying skin. Effect of microneedle pore density and ions in donor formulation was studied. Active enhancement techniques, continuous iontophoresis (74.13?±?2.20?µg/cm²) and microneedles (66.97?±?10.39?µg/cm²), significantly increased the permeation of drug with respect to passive delivery (8.25?±?2.41?µg/cm²). Modulated iontophoresis could control the amount of drug delivered at a given time point with the highest flux being 5.12?±?1.70?µg/cm²/h (5–7?h) and 5.99?±?0.81?µg/cm²/h (20–22?h). Combination of modulated iontophoresis and microneedles (46.50?±?6.46?µg/cm²) showed significantly higher delivery of ropinirole hydrochloride compared to modulated iontophoresis alone (84.91?±?9.21?µg/cm²). Modulated iontophoresis can help in maintaining precise control over ropinirole hydrochloride delivery for dose titration in Parkinson’s disease therapy and deliver therapeutic amounts over a suitable patch area and time.     

Influence of mefenamic acid on the intestinal absorption and metabolism of three bioactive flavones in Radix Scutellariae and potential pharmacological impact

Context: Mefenamic acid (MEF) and the dried root of Scutellaria baicalensis Georgi (Radix Scutellariae, RS) share a high possibility of combined medication to treat inflammation.

Objective: The present study investigates the impact of MEF on absorption/disposition of three major components in RS (baicalein, B; wogonin, W; oroxylin A, OA) and further pharmacological changes.

Materials and methods: The apparent permeability (P_app) and percentage of metabolism of B, W and OA at 10?μΜ were measured at the absence/presence of MEF (100?μΜ) in the Caco-2 cell monolayer model. A modified whole blood assay was employed to quantify prostaglandin E₂ (PGE₂) 4, 6 and 8?h post-oral administration with water suspension of MEF at 40?mg/kg and RS at 200?mg/kg.

Results: In the presence of MEF, P_app of B, W and OA were increased from 1.69?±?0.89?×?10^?6, 1.57?±?0.10?×?10^?6 and 3.09?±?0.70?×?10^?6?cm/sec to 5.24?±?0.27?×?10^?6, 6.08?±?0.19?×?10^?6 and 4.13?±?0.38?×?10^?6, whereas their percentage of metabolism was decreased from 72.75?±?2.44%, 73.27?±?3.25% and 89.84?±?2.99% to 21.11?±?0.69%, 17.90?±?5.55% and 45.44?±?3.38%. PGE₂ level was much lower in the co-administration group (49.04?±?2.03?pg/ml) than in the MEF group (73.13?±?3.03?pg/ml) or RS group (494.37?±?11.75?pg/ml) 4?h post MEF dosing, suggesting a synergic effect.

Discussion and conclusion: Co-administration of MEF and RS could induce potential alterations in their pharmacokinetic profiles and anti-inflammatory effects.     

Sodium cholate,a solubilizing agent for the necrosis avid radioiodinated hypericin in rabbits with acute myocardial infarction

Abstract

Objectives: We determined whether sodium cholate (NaCh) could act as a solubilizing agent for the necrosis avid iodine-123-labeled hypericin (¹²³I-Hyp) and investigated biodistribution and targetability of this formulation in rabbits with acute myocardial infarction (AMI).

Materials and methods: Solubility of radioiodinated hypericin/hypericin (Hyp) in NaCh solutions was evaluated by microscopy. Hyp with ¹²³I-sodium iodide was performed using hydrogen peroxide as oxidant in 0.06?M NaCh. Radiochemical yield determination and purification were conducted using high performance liquid chromatography. ¹²³I-Hyp was solubilized in 0.06?M NaCh containing 1.9?×?10^?4?M Hyp. The formulation was macroscopically inspected and intravenously injected to five rabbits with AMI. At 24?h, biodistribution was evaluated by tissue gamma counting (TGC) and necrosis targetability was assessed by TGC, autoradiography, fluorescence examination and histology.

Results: Microscopically NaCh at 0.06?M shows the best properties for solubilizing the radioiodinated Hyp/Hyp. ¹²³I-Hyp in 0.06?M NaCh was achieved in 85% with radiochemical purity of 99% after purification. NaCh-dissolved ¹²³I-Hyp/Hyp shows no particles. By TGC, animals exhibited higher (p?=?0.003) radioactivity accumulation in AMI (0.8?±?0.2% ID/g) than in normal myocardium (0.05?±?0.02% ID/g), as confirmed by autoradiography, fluorescence measurement and histology. Among organs, the highest uptake of radioactivity was found in liver (15.7?±?0.6% ID), large (9.7?±?1.0% ID) and small (5.9?±?0.6% ID) intestines.

Conclusion: Necrosis avidity of NaCh-dissolved ¹²³I-Hyp/Hyp and its hepatobiliary excretion were demonstrated. The suitability of NaCh as solubilizing agent of ¹²³I-Hyp for hotspot imaging of AMI was proved.     

Study of antidepressant-like activity of an enriched phloroglucinol fraction obtained from Hypericum caprifoliatum

Context: Hypericum caprifoliatum Cham &; Schlecht (Guttiferae) extracts have a potential antidepressant-like effect in rodents. However, the molecular mechanisms by which these extracts exert this effect remain unclear.

Objective: This study evaluated the effect of HC1, a fraction obtained from H. caprifoliatum enriched in phloroglucinol derivatives, on the Na⁺, K⁺ ATPase activity in mouse brain and verified the influence of veratrine on the effect of HC1 in the forced swimming test (FST).

Materials and methods: Veratrine (0.06?mg/kg) and HC1 (360?mg/kg) were given alone or combined i.p. 60 and p.o. 30?min, respectively, before FST. The effect of single and repeated administration (once a day for 3 consecutive days) of HC1 (360?mg/kg) on Na⁺, K⁺ ATPase activity was evaluated ex vivo in the cerebral cortex and hippocampus of mice subjected or not to FST.

Results: HC1 reduced the immobility time (103.15?±?18.67?s), when compared to the control group (183.6?±?9.51?s). This effect was prevented by veratrine (151.75?±?22.19?s). Mice repeatedly treated with HC1 presented a significant increase in Na⁺, K⁺ ATPase activity, both in cerebral cortex (46?±?2.41?nmol Pi/min?mg protein) and hippocampus (49.83?±?2.31?nmol Pi/min?mg protein), in relation to the respective controls (30?±?2.66 and 29.83?±?2.31?nmol Pi/min?mg protein respectively).

Discussion and conclusion: The HC1 antidepressant-like effect on FST might be related to its capacity to inhibit Na⁺?influx. HC1 increases hippocampal and cortical Na⁺, K⁺ ATPase activities possibly through long-term regulatory mechanisms.     

Optimization and evaluation of pluronic lecithin organogels as a transdermal delivery vehicle for sinomenine

The purpose of the present study was to prepare and optimize sinomenine (SIN) pluronic lecithin organogels system (PLO), and to evaluate the permeability of the optimized PLO in vitro and in vivo. Box–Behnken design was used to optimize the PLO and the optimized formulation was pluronic F127 of 19.61%, lecithin of 3.60% and SIN of 1.27%. The formulation was evaluated its skin permeation and drug deposition both in vitro and in vivo compared with gel. Permeation and deposition studies of PLO were carried out with Franz diffusion cells in vitro and with microdialysis in vivo. In vitro studies, permeation rate (J_ss) of SIN from PLO was 146.55?±?2.93?μg/cm²/h, significantly higher than that of gel (120.39?μg/cm²/h) and the amount of SIN deposited in skin from the PLO was 10.08?±?0.86?μg/cm², significantly larger than that from gel (6.01?±?0.04?μg/cm²). In vivo skin microdialysis studies showed that the maximum concentration (C_max) of SIN from PLO in “permeation study” and “drug-deposition study” were 150.27?±?20.85?μg/ml and 67.95?μg/ml, respectively, both significantly higher than that of SIN from gel (29.66 and 6.73?μg/ml). The results recommend that PLO can be used as an advantageous transdermal delivery vehicle to enhance the permeation and skin deposition of SIN.     

Evaluation of turmeric (Curcuma longa) effect on biochemical and pathological parameters of liver and kidney in chicken aflatoxicosis

Context: Aflatoxins as potent mycotoxins can influence vital parameters in chickens. Turmeric was used in decreasing toxic effect of mycotoxins on vital organs, traditionally.

Objective: The study compared the protective effect of turmeric and Mycoad^TR in broilers exposed to aflatoxin.

Materials and methods: Chickens (270) were divided into six groups. The chickens were fed a basal diet, turmeric extract (5?mg/kg diet), Mycoad^TR (25?mg/kg diet), productive aflatoxin (3?mg/kg diet), aflatoxin plus turmeric extract (3 versus 5?mg/kg diet), and aflatoxin plus Mycoad^TR (3 versus 25?mg/kg diet) in basal diet. At 28?d old, we determined plasma concentration of total protein, albumin, triglyceride, cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), calcium, potassium, phosphorous, uric acid, aspartate transferase (AST), and alanine aminotransferase (ALT). Furthermore, liver and kidney were sampled for pathological examination.

Results: Chickens fed turmeric with aflatoxin had significant lower ALT, AST, and uric acid than chickens fed aflatoxin (11.4?±?0.79, 228?±?9, and 6?±?0.4 versus 17.2?±?1.7, 283?±?5, and 7.7?±?0.1) whereas, total protein, calcium, and HDL values in chickens fed aflatoxin plus turmeric increased significantly (2.66?±?0.16, 8.4?±?0.2, and 920?±?4.1 versus 1.7?±?0.17, 7?±?0.2, and 690?±?4.8). Pathological examination revealed severe congestion, degeneration, and necrosis in liver and kidney in chickens that received aflatoxin.

Discussion and conclusion: The study showed that turmeric may provide protection against the toxic effects of aflatoxin on liver and kidney.     

Preparation,characterization, and biodistribution of breviscapine proliposomes in heart

Breviscapine proliposomes were prepared by ethanol injection–homogenization–lyophilization method. On contact with 5% glucose, the proliposomes were rapidly converted into a liposomal dispersion, in which a certain amount of breviscapine was entrapped by the liposomes. The entrapment efficiency measured by reverse dialysis method was 77.89?±?0.28%. The particle size, polydispersity index, and zeta potential of breviscapine liposomes were 504.83?±?52.88?nm (by intensity), 0.17?±?0.02, and ?(20.31?±?1.03) mV, respectively (mean ± SD, n = 3). In mimic-biomembrane model experiment, breviscapine was distributed not only to n-octanol and buffer phase but also to interfacial phase. After bolus administration, the elimination phase (t_1/2(β) = 66.386) of liposomal formulation in plasma was 4.8 times longer than that of solution formulation (t_1/2(β) = 13.695). The AUC and MRT values of liposomal formulation in heart were increased more than 11.7- and 3.2-fold versus solution formulation, respectively. These results were all beneficial to heart disease therapy.     

Cis-resveratrol glucuronidation kinetics in human and recombinant UGT1A sources

1. It was hypothesized that cis-resveratrol glucuronidation contributes to a greater extent to in-vitro disposition of total resveratrol than previously assumed. To this end, the kinetic data for cis-resveratrol glucuronidation are reported.

2. Glucuronidation assays were conducted in human liver and intestinal microsomes and in uridine diphosphate-glucuronosyltransferases (UGTs) UGT1A1, UGT1A6, UGT1A9, and UGT1A10. Kinetic parameters were estimated for the major cis-resveratrol-3-O-glucuronide (cis-R3G). Substrate inhibition was observed with apparent V_max, K_m and K_i of 6.1?±?0.3/27.2?±?1.2 nmol min^?1 mg^?1, 415?±?48.1/989.9?±?92.8 and 789.6?±?76.3/1012?±?55.9?μM in human intestinal microsomes (HIMs) and UGT1A6, respectively (estimate?±?standard error (SE)). Biphasic kinetics were observed in human liver microsomes (HLMs), while sigmoidal kinetics were seen in UGT1A9 (V_max?=?11.92?±?0.2 nmol min^?1 mg^?1; K_m?=?360?μM; n?=?1.27?±?0.07). The 4′-O-glucuronide (cis-R4′G) exhibited atypical kinetics in HLM, HIM, UGT1A1, and UGT1A10. UGT1A9 catalysed cis-R4′G formation at high substrate concentrations (V_max?=?0.33?±?0.015 nmol min^?1 mg^?1; K_m?=?537.8?±?67.8?μM).

3. In conclusion, although the rates of formation of cis-R3G in HLM and UGT1A9 were higher than those for trans-R3G, the contribution to total resveratrol disposition could not be determined fully due to atypical kinetics observed.