Improving relative bioavailability of dicumarol by reducing particle size and adding the adhesive poly(fumaric-co-sebacic) anhydride

Biocoating-A Critical Step Governing the Oral Delivery of Polymeric Nanoparticles

Decades of research into the topic of oral nanoparticle (NP) delivery has still not provided a clear consensus regarding which properties produce an effective oral drug delivery system. The surface properties-charge and bioadhesiveness-as well as in vitro and in vivo correlation seem to generate the greatest number of disagreements within the field. Herein, a mechanism underlying the in vivo behavior of NPs is proposed, which bridges the gaps between these disagreements. The mechanism relies on the idea of biocoating-the coating of NPs with mucus-which alters their surface properties, and ultimately their systemic uptake. Utilizing this mechanism, several coated NPs are tested in vitro, ex vivo, and in vivo, and biocoating is found to affect NPs size, zeta-potential, mucosal diffusion coefficient, the extent of aggregation, and in vivo/in vitro/ex vivo correlation. Based on these results, low molecular weight polylactic acid exhibits a 21-fold increase in mucosal diffusion coefficient after precoating as compared to uncoated particles, as well as 20% less aggregation, and about 30% uptake to the blood in vivo. These discoveries suggest that biocoating reduces negative NP charge which results in an enhanced mucosal diffusion rate, increased gastrointestinal retention time, and high systemic uptake.

A pharmacological review of dicoumarol: An old natural anticoagulant agent

Dicoumarol is an oral anticoagulant agent prescribed in clinical for decades. It is a natural hydroxycoumarin discovered from the spoilage of Melilotus officinalis (L.) Pall and is originally discovered as a rodenticide. Due to its structural similarity to that of vitamin K, it significantly inhibits vitamin K epoxide reductase and acts as a vitamin K antagonist. Dicoumarol is mainly used as an anticoagulant to prevent thrombogenesis and to cure vascular thrombosis. Other biological activities besides anticoagulants such as anticancer, antimicrobial, antiviral, etc., have also been documented. The side effects of dicoumarol raise safety concerns for clinical application. In this review, the physicochemical property, the pharmacological activities, the side effects, and the pharmacokinetics of dicoumarol were summarized, aiming to provide a whole picture of the "old" anticoagulant.

The Arachis hypogaea Essential Oil Nanoemulsion as an Efficient Safe Apoptosis Inducer in Human Lung Cancer Cells (A549)

Nanoemulsions have improved therapeutic efficiency. In this regard, due to the Arachis hypogaea components such as flavonoids, we planned to produce Arachis hypogaea oil nanoemulsion (AHO-NE) in order to evaluate its anticancer impacts on A549 lung cancer cells.  The AHO-NE was formulated by ultrasonication, characterized, and used in treating A549 cells. Then, we evaluated Caspase-3 gene expression, flow cytometry results, and MTT assay on A549 cells to check its anticancer impacts. The 50.3 nm AHO-NE significantly reduced the of A549 cells' viability comparing with HFF normal cells. The increasing SubG1 peaks and Cas3 overexpression indicate the AHO-NE apoptotic impact on A549 cells. We found its antioxidant activity (ABTS IC₅₀ = 270.42 μg/ml and DPPH IC₅₀ = 208.51 μg/ml). In conclusion, AHO-NE has the potential to be used as an exclusive cell-dependent anticancer compound in A549 lung cancer cells.

Citrus aurantium L. bloom essential oil nanoemulsion: Synthesis, characterization, cytotoxicity, and its potential health impacts on mice

This research was performed to synthesize the Citrus aurantium L. bloom essential oil nanoemulsion (CABE-NE) and investigate its cytotoxic and apoptotic impacts on human lung (A549 cells), and further, the effects of CABE-NE on mice health parameters was determined. The obtained results demonstrated that C. aurantium bloom contained 1.2 ± 0.16% of essential oil with linalyl acetate, limonene, and α-terpineol as major compounds. The CABE-NE possessed particle size of 76.9 ± 6.11 nm, PDI of 0.19, and zeta potential of -43.5 mV. The CABE-NE indicated the cytotoxicity against A549 cells with the IC₅₀ value of 152 µg/ml. The CABE-NE induced the overexpression of Cas-3 and triggered the apoptotic cells death. The mice gavaged daily with CABE-NE at the concentrations of 10 and 20 mg/kg body weight for 30 days did not show any remarkable histopathological alteration in the liver and kidney while exhibited enhancement in the jejunum morpho-structural architecture and hepatic antioxidant redox potential. PRACTICAL APPLICATIONS: According to the results, the produced CABE-NE drug delivery system could be considered as a promising alternative to prevent lung cancer progression and it provides a new way to enhance the therapeutic value of the plant phytochemicals.

Producing the sour cherry pit oil nanoemulsion and evaluation of its anti-cancer effects on both breast cancer murine model and MCF-7 cell line

Aims: The sour cherry pit oil (SCPO) displays the potent anti-inflammatory, and antioxidant activities. In the present study, we have produced the SCPO nanoemulsion (SCPO-NE) to evaluate their anticancer impacts on breast cancer comparing with its un-processed oil. Methods: We employed an ultrasonication method to formulate the stable SCPO-NE. Their size, stability, and morphology were measured. Then, their cytotoxic impacts and apoptotic activity were checked on MCF7 breast cancer cells and compared with the normal Human foreskin fibroblasts (HFF). Finally, their anti-tumour effect was studied on murine breast cancer model (inoculated with TUBO cancer cells). Results: The results indicated the 36.5 nm stable SCPO-NE significantly decreased the MCF7 cells viability comparing with normal HFF cells, and reduced the tumour size in the murine model. Conclusion: We suggest that SCPO-NEs are able to efficiently inhibit breast cancer progression in both MCF7 cells and murine breast cancer model through apoptotic death induction.

Improving Relative Bioavailability of Oral Imidazolidinedione by Reducing Particle Size Using Homogenization and Ultra-Sonication

Particle size is an important determinant of gastrointestinal absorption of compounds administrated orally. The present study evaluates the effect of a reduction in particle size assessed by homogenization, sonication, and homogenization plus sonication on the bioavailability of imidazolidinedione (IZ), an antimalarial compound with known causal prophylactic activity and radical cure of relapsing malaria. Formulations were administrated intragastrically to mice, and blood samples were collected for LC-MS/MS analysis. The homogenization method manually decreased particle size with minimal variance, resulting in a mean particle diameter of 42.22 μm, whereas the probe sonication method evenly distributed pulses of sound to break apart particles, resulting in a mean diameter of 1.50 μm. Homogenization plus sonication resulted in a mean particle diameter of 1.44 μm, which was similar to that of the sonication method alone. The compound suspensions did not show a significant difference in mean particle size between the different vehicles. The sonically engineered microparticle delivers high sonic energy to the suspension leads to faster breakdown and stabilizing of the micronized particles when compared with homogenizer. The bioavailability of the small particle IZ formulation was 100%, compared to the 55.79% relative bioavailability of IZ with larger particle size. These initial data clearly show that a reduction in particle size of orally administered IZ with probe sonication could significantly increase bioavailability in rodent animals that is affected by a high first-pass effect.

Intestinal Uptake of Polymer Microspheres in the Rabbit Studied with Confocal Microscopy

This study characterizes the ability of several polymer formulations to penetrate the absorptive epithelium and lymphoid-associated tissue of the gastrointestinal tract. Using phase inversion nano encapsulation and solvent diffusion, formulations with variable size ranges consisting of either poly(fumaric-co-sebacic)anhydride, poly(lactide-co-glycolide), polystyrene, or polycaprolactone were fabricated and administered to an isolated loop in the small intestine of rabbits. Particles were loaded with a fluorescent dye for detection. Following a period of incubation, animals were sacrificed and the tissue was explanted and processed for histology. Confocal laser scanning microscopy (CLSM) was used to track the microspheres and two separate emission detectors were used to isolate the dye from background. Particles that possess bioadhesiveness in the micron size range could be localized to the absorptive epithelium while larger particles and formulations with low bioadhesiveness failed to penetrate enterocytes and were taken up preferentially in the Peyer’s patches. This work demonstrates that the surface chemistry of oral formulations can ultimately determine the fate and can aid in designing delivery vehicles for a variety of therapeutics currently plagued with poor oral bioavailability.

Leveraging BCS in Development: A Case Study

In this work, we discuss leveraging the Biopharmaceutics Classification System (BCS) in the development of edivoxetine HCl, a selective norepinephrine reuptake inhibitor. First, the biopharmaceutical and in vivo data are presented and discussed. Solubility studies indicate that edivoxetine HCl meets the BCS "highly soluble" criteria. To determine permeability classifications, in vitro intestinal Caco-2 epithelial cell model with and without cyclosporin A (CsA), a common P-glycoprotein (P-gp) inhibitor, were conducted. Pharmacokinetic (PK) data obtained across phase 1 and 2 clinical studies where single and multiple doses range from the lowest to the highest strength are presented. Neither the Caco-2 nor the in vivo data on their own were sufficient to conclusively classify edivoxetine as highly permeable. However, collectively the data were utilized to support high permeability and consequently BCS1 classification of edivoxetine HCl. BCS1 classification was leveraged throughout development to assess the risk associated with not conducting relative bioavailability (RBA) studies and avoiding bioequivalence (BE) studies. Examples are presented where formulation changes were made between phase I (drug in capsule/drug in bottle formulations) and phase II (tablet) trials in addition to phase III (tablet) and commercial (smaller tablet) without having to conduct any in vivo comparability studies. For the first change, BCS was leveraged to avoid conducting a RBA study even before obtaining official BCS classification. For the later change, official BCS1 classification was relied upon to avoid conducting a BE study.

Polyanhydride nanoparticles by ‘click’ thiol–ene polymerization

The production of degradable polyanhydride-based nanoparticles using thiol–ene ‘click’ polymerizations is described.

Unique insights into the intestinal absorption, transit, and subsequent biodistribution of polymer-derived microspheres

Polymeric microspheres (MSs) have received attention for their potential to improve the delivery of drugs with poor oral bioavailability. Although MSs can be absorbed into the absorptive epithelium of the small intestine, little is known about the physiologic mechanisms that are responsible for their cellular trafficking. In these experiments, nonbiodegradable polystyrene MSs (diameter range: 500 nm to 5 µm) were delivered locally to the jejunum or ileum or by oral administration to young male rats. Following administration, MSs were taken up rapidly (≤ 5 min) by the small intestine and were detected by transmission electron microscopy and confocal laser scanning microscopy. Gel permeation chromatography confirmed that polymer was present in all tissue samples, including the brain. These results confirm that MSs (diameter range: 500 nm to 5 µm) were absorbed by the small intestine and distributed throughout the rat. After delivering MSs to the jejunum or ileum, high concentrations of polystyrene were detected in the liver, kidneys, and lungs. The pharmacologic inhibitors chlorpromazine, phorbol 12-myristate 13-acetate, and cytochalasin D caused a reduction in the total number of MSs absorbed in the jejunum and ileum, demonstrating that nonphagocytic processes (including endocytosis) direct the uptake of MSs in the small intestine. These results challenge the convention that phagocytic cells such as the microfold cells solely facilitate MS absorption in the small intestine.

Formulation and particle size reduction improve bioavailability of poorly water-soluble compounds with antimalarial activity

Decoquinate (DQ) is highly effective at killing malaria parasites in vitro; however, it is extremely insoluble in water. In this study, solid dispersion method was used for DQ formulation which created a suitable physical form of DQ in aqueous phase for particle manipulation. Among many polymers and surfactants tested, polyvinylpyrrolidone 10, a polymer, and L-α-phosphatidylcholine or polysorbate, two surfactants, were chosen as DQ formulation components. The formulation particles were reduced to a mean size between 200 to 400 nm, which was stable in aqueous medium for at least three weeks. Pharmacokinetic (PK) studies showed that compared to DQ microparticle suspension, a nanoparticle formulation orally dosed to mice showed a 14.47-fold increase in area under the curve (AUC) of DQ plasma concentration and a 4.53-fold increase in AUC of DQ liver distribution. WR 299666, a poorly water-soluble compound with antimalarial activity, was also tested and successfully made into nanoparticle formulation without undergoing solid dispersion procedure. We concluded that nanoparticles generated by using appropriate formulation components and sufficient particle size reduction significantly increased the bioavailability of DQ and could potentially turn this antimalarial agent to a therapeutic drug.

Fabrication, modeling and characterization of multi-crosslinked methacrylate copolymeric nanoparticles for oral drug delivery

Nanotechnology remains the field to explore in the quest to enhance therapeutic efficacies of existing drugs. Fabrication of a methacrylate copolymer-lipid nanoparticulate (MCN) system was explored in this study for oral drug delivery of levodopa. The nanoparticles were fabricated employing multicrosslinking technology and characterized for particle size, zeta potential, morphology, structural modification, drug entrapment efficiency and in vitro drug release. Chemometric Computational (CC) modeling was conducted to deduce the mechanism of nanoparticle synthesis as well as to corroborate the experimental findings. The CC modeling deduced that the nanoparticles synthesis may have followed the mixed triangular formations or the mixed patterns. They were found to be hollow nanocapsules with a size ranging from 152 nm (methacrylate copolymer) to 321 nm (methacrylate copolymer blend) and a zeta potential range of 15.8–43.3 mV. The nanoparticles were directly compressible and it was found that the desired rate of drug release could be achieved by formulating the nanoparticles as a nanosuspension, and then directly compressing them into tablet matrices or incorporating the nanoparticles directly into polymer tablet matrices. However, sustained release of MCNs was achieved only when it was incorporated into a polymer matrix. The experimental results were well corroborated by the CC modeling. The developed technology may be potentially useful for the fabrication of multi-crosslinked polymer blend nanoparticles for oral drug delivery.

Partial correction of cystic fibrosis defects with PLGA nanoparticles encapsulating curcumin

Cystic fibrosis (CF) is a common life threatening genetic disease (incidence: approximately 1 in 2500 live births). CF is caused by mutations in CFTR, a chloride channel involved in epithelial secretion of fluid and electrolytes. The most common mutation entails the deletion of a phenylalanine in position 508 that causes protein misfolding and abnormal CFTR processing. The DeltaF508 mutation accounts for approximately 70% of all CF alleles, and about 90% of CF patients carry at least one copy of DeltaF508 CFTR. Curcumin, a natural constituent of Curcuma longa (turmeric spice), is a nontoxic low-affinity SERCA (sarco (endo)plasmic reticulum calcium ATPase) pump inhibitor thought to permit DeltaF508 CFTR escape from the ER. The compound has been shown to be capable of correcting the defect in cell lines and mice expressing DeltaF508 CFTR. In this work, poly lactic-co-glycolic acid (PLGA) nanoparticles encapsulating curcumin were synthesized and used to treat two different CF mouse strains in an effort to correct the defects associated with CF by improving bioavailability of the compound, which has previously been a challenge in treatment with curcumin. Our results suggest that oral administration of PLGA nanoparticles encapsulating curcumin enhances the effects of curcumin therapy in CF mice, as compared to delivery of nonencapsulated curcumin.

Enhancement of anti-inflammatory property of aspirin in mice by a nano-emulsion preparation

Aspirin, a non-steroidal anti-inflammatory drug, widely used for its anti-inflammatory properties is associated with several systemic side effects including gastro-intestinal discomfort. Inflammation can be mediated by pro-inflammatory cytokines and, along with various other host factors eventually give rise to edema at the inflamed site. Because of the adverse side effects oftentimes associated with systemic exposure to aspirin, the aim of the present study was to investigate whether the anti-inflammatory property of aspirin would enhance if delivered as nano-emulsion preparation. Nano-emulsion preparations of aspirin prepared with a Microfluidizer Processor were evaluated in the croton-oil-induced ear edema CD-1 mouse model using ear lobe thickness and the accumulation of specific in situ cytokines as biomarkers of inflammation. The results showed that particle size (90 nm) populations of nano-emulsion preparations of aspirin compared to an aspirin suspension (363 nm), significantly decreased (p<0. 05) ear lobe thickness approximately 2 fold greater than the aspirin suspension. In addition, the aspirin nano-emulsion further reduced the auricular levels of IL-1alpha (-37%) and TNFalpha (-69%) compared to the aspirin suspension preparation (p<0.05). The reductions in ear lobe thickness were also significantly associated with accumulated tissue levels of IL-1alpha (r=0.5, p<0.009) and TNFalpha (r=0.7, p<0.0004), respectively. In conclusion, these studies indicate that a nano-emulsion preparation of aspirin significantly improved the anti-inflammatory properties of an aspirin suspension in a CD-1 mouse model of induced inflammation.

A nanoemulsion formulation of tamoxifen increases its efficacy in a breast cancer cell line

This paper reports on the preparation of a water-soluble nanoemulsion of the highly lipid-soluble drug tamoxifen (TAM). In addition, relative to a suspension of TAM, the nanoemulsion preparation demonstrated a greater zeta potential (increased negative charge) which has previously been associated with increasing drug/membrane permeability. This study also reports that relative to suspensions of TAM with particle sizes greater than 6000 nm, nanoemulsions of TAM, having mean particle sizes of 47 nm, inhibited cell proliferation 20-fold greater and increased cell apoptosis 4-fold greater in the HTB-20 breast cancer cell line. Thus, this work suggests that a nanoemulsion compared to a suspension preparation of TAM increases its anticancer properties relative to breast cancer.

Increased bioavailability of a transdermal application of a nano-sized emulsion preparation

The aim of this study was to compare the transdermal application of a nano-sized emulsion versus a micron-sized emulsion preparation of delta tocopherol as it relates to particle size and bioavailability. Two separate experiments were performed using seven F1B Syrian Golden hamsters, 1 week apart. Each emulsion preparation consisted of canola oil, polysorbate 80, deionized water and delta tocopherol; the only difference between the two preparations was processing the nano-sized emulsion with the Microfluidizer Processor. Both were formulated into a cream and applied to the shaven dorsal area. The particle size of the micron-sized emulsion preparation was 2788 nm compared to 65 nm for the nano-sized emulsion formulation. Two hours post-application, hamsters that were applied the nano-sized emulsion had a 36-fold significant increase of plasma delta tocopherol, where as hamsters that were applied the micron-sized emulsion only had a 9-fold significant increase, compared to baseline, respectively. At 3h post-application, plasma delta tocopherol had significantly increased 68-fold for hamsters applied the nano-sized emulsion, whereas only an 11-fold significant increase was observed in hamsters applied the micron-sized emulsion, compared to baseline, respectively. Significant differences were also observed between the nano-sized and micron-sized emulsion at 2 and 3h post-application. This study suggests that nano-sized emulsions significantly increase the bioavailability of transdermally applied delta tocopherol.

Targeted nanoparticle-based drug delivery and diagnosis

Nanotechnology, or systems/device manufacture at sizes generally ranging between 1 and 100 nm, is a multidisciplinary scientific field undergoing explosive development. The genesis of nanotechnology can be traced to advances in medicine, communications, genomics and robotics. One of the greatest values of nanotechnology will be in the development of new and effective medical treatments (i.e. nanomedicine). This review focuses on the potential of nanomedicine as it relates to the development of nanoparticles for enabling and improving the targeted delivery of therapeutic and diagnostic agents. We highlight the use of nanoparticles for specific intra-compartmental analysis using the examples of delivery to malignant cancers, to the central nervous system, and across the gastrointestinal barriers.