Pharmacokinetics and pharmacodynamics of chlorambucil delivered in long-circulating nanoemulsion

Preparation of a nanoemulsion containing active ingredients of cannabis extract and its application for glioblastoma: in vitro and in vivo studies

Recently, the anti-tumor effects of cannabis extract on various cancers have attracted the attention of researchers. Here, we report a nanoemulsion (NE) composition designed to enhance the delivery of two active components in cannabis extracts (∆9-Tetrahydrocannabinol (THC) and Cannabidiol (CBD)) in an animal model of glioblastoma. The efficacy of the NE containing the two drugs (NED) was compared with the bulk drugs and carrier (NE without the drugs) using the C6 tumor model in rats. Hemocompatibility factors (RBC, MCV, MCH, MCHC, RDW, PPP, PT and PTT) were studied to determine the potential in vivo toxicity of NED. The optimized NED with mean ± SD diameter 29 ± 6 nm was obtained. It was shown that by administering the drugs in the form of NED, the hemocompatibility increased. Cytotoxicity studies indicated that the NE without the active components (i.e. mixture of surfactants and oil) was the most cytotoxic group, while the bulk group had no toxicity. From the in vivo MRI and survival studies, the NED group had maximum efficacy (with ~4 times smaller tumor volume on day 7 of treatment, compared with the control. Also, survival time of the control, bulk drug, NE and NED were 9, 4, 12.5 and 51 days, respectively) with no important adverse effects. In conclusion, the NE containing cannabis extract could be introduced as an effective treatment in reducing brain glioblastoma tumor progression.

Immunomodulatory and immune-toxicological role of nanoparticles: Potential therapeutic applications

Nowadays, Nanoparticle-based immunotherapeutic research has invoked global interest due to their unique properties. The immune system is a shielding structure that defends living things from external threats. Before the use of any materials in drug design, it is essential to study the immunological response to avoid triggering undesirable immune responses in the body. This review tries to summarize the properties, various applications, and immunotherapeutic aspects of NP-induced immunomodulation relating to therapeutic development and toxicity in human health. The role of NPs in the immune system and their modulatory functions, resulting in immunosuppression or immunostimulation, exerts benefits or dangers depending on their compositions, sizes, surface chemistry, and so forth. After NPs enter into the body, they can interact with body fluid exposing, them to different body proteins to form protein corona particles and other bio-molecules (DNA, RNA, sugars, etc.), which may alter their bioactivity. Phagocytes are the first immune cells that can interact with foreign materials including nanoparticles. Immunostimulation and immunosuppression operate in two distinct manners. Overall, functionalized nanocarriers optimized various therapeutic implications by stimulating the host immune system and regulating the tranquility of the host immune system. Among others, toxicity and bio-clearance of nanomaterials are always prime concerns at the preclinical and clinical stages before final approval. The interaction of nanoparticles with immune cells causes direct cell damage via apoptosis and necroses as well as immune signaling pathways also become influenced.

Influence of Poloxamer 188 on Anti-Inflammatory and Analgesic Effects of Diclofenac-Loaded Nanoemulsion: Formulation, Optimization and in Vitro/in Vivo Evaluation

In this study, a polymer-stabilized nanoemulsion (PNE) was developed to improve the inflammatory and analgesic activities of diclofenac (DA). DA-PNEs were prepared from sesame oil and poloxamer 188 (P188), polysorbate 80, and span 80 as emulsifiers and optimized by a systematic multi-objective optimization method. The developed DA-PNEs exhibited thermodynamical stability with low viscosity. The mean diameter, PDI, surface charge, and entrapment efficiency of DA-PNEs were 122.49±3.42 nm, 0.226±0.08, -47.3 ± 3.6 mV, and 93.57±3.4 %, respectively. The cumulative in vitro release profile of DA-PNEs was significantly higher than the neat drug in simulated gastrointestinal fluids. The anti-inflammatory activities of DA-PNEs were evaluated in the λ-carrageenan-induced paw edema model. To investigate the effect of P188 on analgesic and anti-inflammatory activities, a formulation without P188 was also prepared and named DA-NEs. Following oral administration, DA-PNEs showed a significantly higher (p<0.05) effect in reducing pain and inflammation symptoms as compared to free diclofenac and DA-NEs. Moreover, histopathological examination confirmed that DA-PNEs meaningfully reduced the extent of paw edema, comparable to that of DA. Taken together, the findings of the in vitro and in vivo studies suggest that diclofenac-loaded P188-stabilized nanoemulsion can be considered a potential drug delivery system for treating and controlling inflammatory disorders and alleviating pains.

Nanoemulsion: An Emerging Novel Technology for Improving the Bioavailability of Drugs

The pharmaceutical sector has made considerable strides recently, emphasizing improving drug delivery methods to increase the bioavailability of various drugs. When used as a medication delivery method, nanoemulsions have multiple benefits. Their small droplet size, which is generally between 20 and 200 nanometers, creates a significant interfacial area for drug dissolution, improving the solubility and bioavailability of drugs that are weakly water-soluble. Additionally, nanoemulsions are a flexible platform for drug administration across various therapeutic areas since they can encapsulate hydrophilic and hydrophobic medicines. Nanoemulsion can be formulated in multiple dosage forms, for example, gels, creams, foams, aerosols, and sprays by using low-cost standard operative processes and also be taken orally, topically, topically, intravenously, intrapulmonary, intranasally, and intraocularly. The article explores nanoemulsion formulation and production methods, emphasizing the role of surfactants and cosurfactants in creating stable formulations. In order to customize nanoemulsions to particular medication delivery requirements, the choice of components and production techniques is crucial in assuring the stability and efficacy of the finished product. Nanoemulsions are a cutting-edge technology with a lot of potential for improving medication bioavailability in a variety of therapeutic contexts. They are a useful tool in the creation of innovative pharmaceutical formulations due to their capacity to enhance drug solubility, stability, and delivery. Nanoemulsions are positioned to play a crucial role in boosting medication delivery and enhancing patient outcomes as this field of study continues to advance.

Genotoxicity of cytokines at chemotherapy-induced 'storm' concentrations in a model of the human bone marrow

Donor cell leukaemia (DCL) is a complication of haematopoietic stem cell transplantation where donated cells become malignant within the patient's bone marrow. As DCL predominates as acute myeloid leukaemia, we hypothesized that the cytokine storm following chemotherapy played a role in promoting and supporting leukaemogenesis. Cytokines have also been implicated in genotoxicity; thus, we explored a cell line model of the human bone marrow (BM) to secrete myeloid cytokines following drug treatment and their potential to induce micronuclei. HS-5 human stromal cells were exposed to mitoxantrone (MTX) and chlorambucil (CHL) and, for the first time, were profiled for 80 cytokines using an array. Fifty-four cytokines were detected in untreated cells, of which 24 were upregulated and 10 were downregulated by both drugs. FGF-7 was the lowest cytokine to be detected in both untreated and treated cells. Eleven cytokines not detected at baseline were detected following drug exposure. TNFα, IL6, GM-CSF, G-CSF, and TGFβ1 were selected for micronuclei induction. TK6 cells were exposed to these cytokines in isolation and in paired combinations. Only TNFα and TGFβ1 induced micronuclei at healthy concentrations, but all five cytokines induced micronuclei at storm levels, which was further increased when combined in pairs. Of particular concern was that some combinations induced micronuclei at levels above the mitomycin C positive control; however, most combinations were less than the sum of micronuclei induced following exposure to each cytokine in isolation. These data infer a possible role for cytokines through chemotherapy-induced cytokine storm, in the instigation and support of leukaemogenesis in the BM, and implicate the need to evaluate individuals for variability in cytokine secretion as a potential risk factor for complications such as DCL.

Lipid-engineered nanotherapeutics for cancer management

Cancer causes significant mortality and morbidity worldwide, but existing pharmacological treatments are greatly limited by the inherent heterogeneity of cancer as a disease, as well as the unsatisfactory efficacy and specificity of therapeutic drugs. Biopharmaceutical barriers such as low permeability and poor water solubility, along with the absence of active targeting capabilities, often result in suboptimal clinical results. The difficulty of successfully reaching and destroying tumor cells is also often compounded with undesirable impacts on healthy tissue, including off-target effects and high toxicity, which further impair the ability to effectively manage the disease and optimize patient outcomes. However, in the last few decades, the development of nanotherapeutics has allowed for the use of rational design in order to maximize therapeutic success. Advances in the fabrication of nano-sized delivery systems, coupled with a variety of surface engineering strategies to promote customization, have resulted in promising approaches for targeted, site-specific drug delivery with fewer unwanted effects and better therapeutic efficacy. These nano systems have been able to overcome some of the challenges of conventional drug delivery related to pharmacokinetics, biodistribution, and target specificity. In particular, lipid-based nanosystems have been extensively explored due to their high biocompatibility, versatility, and adaptability. Lipid-based approaches to cancer treatment are varied and diverse, including liposomal therapeutics, lipidic nanoemulsions, solid lipid nanoparticles, nanostructured lipidic carriers, lipid-polymer nanohybrids, and supramolecular nanolipidic structures. This review aims to provide an overview of the use of diverse formulations of lipid-engineered nanotherapeutics for cancer and current challenges in the field, as researchers attempt to successfully translate these approaches from bench to clinic.

In vivo antitumor activity study of targeted chlorambucil-loaded nanolipid carrier for breast cancer

Chlorambucil (CBL) is an efficient anticancer drug. It is a lipophilic agent with serious adverse effects. The objective of this study was to formulate a CBL-loaded nanolipid carrier and target breast cancer using folic acid as a targeting probe. Characterizations of the optimum formulation were 79.9±3% EE after the addition of 4mg CBL, 119±6nm particle size which is considered appropriate for parenteral use, 0.3±0.02 PDI, -42±1mV ZP that stabilized the formulation. Tumor volume, body weight, and tumor mass weight were recorded to evaluate tumor volume doubling time, tumor growth inhibition rate, and systemic toxicity. It appeared there was a significant antitumor activity of targeted formulation compared with non-targeted one and free CBL. Moreover, the systemic toxicity was less after body weight evaluation concerning the targeted formulation when compared with other formulations.

Nanoemulsions Containing Megestrol Acetate: Development, Characterization, and Stability Evaluation

Many active pharmaceutical ingredients (API) are poorly soluble in water and their low oral bioavailability is a major hindrance to their potential use. Megestrol acetate (MGA) is insoluble in water and its oral absorption is limited and considerably affected by food. Nanoemulsions (NEs) can be used as effective oral drug delivery systems where the hydrophobic API is loaded into the oil phase. In this study, MGA-loaded NEs were prepared based on the spontaneous emulsification technique. The effects of different excipients such as ethanol, Tween 80, Lipoid E80, and medium-chain triglyceride (MCT) on the NEs characterization were investigated. The experimental results indicated that optimum MGA-loaded NEs (F20) were nanometer-sized droplets (166.9 ± 3.0 nm) with negative zeta potential (-12.2 ± 1.1 mV). The effect of polyvinylpyrrolidone (PVP) on characteristic properties of F20 was also evaluated. On the selected NEs, in vitro dissolution tests and stability studies in various mediums and storage conditions were performed. The encapsulation efficiency of NEs were > 99%. The overall droplet size of F20 and PVP-2 (PVP-coated NEs) remained relatively stable as the pH changed from 1.2 to 6.8. It was determined that F20 and PVP-2 remained stable at 4°C until 12 weeks and had higher cytotoxicity on MCF-7 cells. To conclude, droplet size, surface charge, and stability are important properties for NEs to have sufficient effectiveness. In this study, alternative oral NEs of low-solubility drug MGA were developed considering the above features.

Recent Progress in Nanostructured Smart Drug Delivery Systems for Cancer Therapy: A Review

Traditional treatment approaches for cancer involve intravenous chemotherapy or other forms of drug delivery. These therapeutic measures suffer from several limitations such as nonspecific targeting, poor biodistribution, and buildup of drug resistances. However, significant technological advancements have been made in terms of superior modes of drug delivery over the last few decades. Technical capability in analyzing the molecular mechanisms of tumor biology, nanotechnology─particularly the development of biocompatible nanoparticles, surface modification techniques, microelectronics, and material sciences─has increased. As a result, a significant number of nanostructured carriers that can deliver drugs to specific cancerous sites with high efficiency have been developed. This particular maneuver that enables the introduction of a therapeutic nanostructured substance in the body by controlling the rate, time, and place is defined as the nanostructured drug delivery system (NDDS). Because of their versatility and ability to incorporate features such as specific targeting, water solubility, stability, biocompatibility, degradability, and ability to reverse drug resistance, they have attracted the interest of the scientific community, in general, and nanotechnologists as well as biomedical scientists. To keep pace with the rapid advancement of nanotechnology, specific technical aspects of the recent NDDSs and their prospects need to be reported coherently. To address these ongoing issues, this review article provides an overview of different NDDSs such as lipids, polymers, and inorganic nanoparticles. In addition, this review also reports the challenges of current NDDSs and points out the prospective research directions of these nanocarriers. From our focused review, we conclude that still now the most advanced and potent field of application for NDDSs is lipid-based, while other significantly potential fields include polymer-based and inorganic NDDSs. However, despite the promises, challenges remain in practical implementations of such NDDSs in terms of dosage and stability, and caution should be exercised regarding biocompatibility of materials. Considering these aspects objectively, this review on NDDSs will be particularly of interest for small-to-large scale industrial researchers and academicians with expertise in drug delivery, cancer research, and nanotechnology.

Exploring Nanoemulsions for Prostate Cancer Therapy

Prostate carcinoma is typical cancer. It is the second most common cancer globally. The estimated new cases in 2020 was 191 930 and estimated deaths was 33 330. Age, family history, & genetic factors are major factors that drive prostate cancer. Although, for treating metastatic disease, the major therapies available are radiation,bisphosphonate, and palliative chemotherapy. But the major drawback is therapy is disease-driven and later becomes metastatic and requires treatment. The ability to revolutionize cancer treatment by major targeting vehicles via the exploration of nanoemulsion suggests a potential for cancer treatment. The unique property of a biphasic liquid dosage form called nanoemulsion to reach leaky tumor vasculature is due to its nano-meter oil-droplet size of 20-200 nm. Recent reporting on nanoemulsions disclose their embracing and lay alternative for re-purposing herbal and synthetic drugs and their combination especially for targeting prostate cancer formulating an obtainable nanomedicine. So, this article emphasizes the use of nanoemulsions incorporating therapeutic agents for successful and targeted delivery for prostate cancer.

A Nano-Emulsion Platform Functionalized with a Fully Human scFv-Fc Antibody for Atheroma Targeting: Towards a Theranostic Approach to Atherosclerosis

Atherosclerosis is at the onset of the cardiovascular diseases that are among the leading causes of death worldwide. Currently, high-risk plaques, also called vulnerable atheromatous plaques, remain often undiagnosed until the occurrence of severe complications, such as stroke or myocardial infarction. Molecular imaging agents that target high-risk atheromatous lesions could greatly improve the diagnosis of atherosclerosis by identifying sites of high disease activity. Moreover, a "theranostic approach" that combines molecular imaging agents (for diagnosis) and therapeutic molecules would be of great value for the local management of atheromatous plaques. The aim of this study was to develop and characterize an innovative theranostic tool for atherosclerosis. We engineered oil-in-water nano-emulsions (NEs) loaded with superparamagnetic iron oxide (SPIO) nanoparticles for magnetic resonance imaging (MRI) purposes. Dynamic MRI showed that NE-SPIO nanoparticles decorated with a polyethylene glycol (PEG) layer reduced their liver uptake and extended their half-life. Next, the NE-SPIO-PEG formulation was functionalized with a fully human scFv-Fc antibody (P3) recognizing galectin 3, an atherosclerosis biomarker. The P3-functionalized formulation targeted atheromatous plaques, as demonstrated in an immunohistochemistry analyses of mouse aorta and human artery sections and in an Apoe^-/- mouse model of atherosclerosis. Moreover, the formulation was loaded with SPIO nanoparticles and/or alpha-tocopherol to be used as a theranostic tool for atherosclerosis imaging (SPIO) and for delivery of drugs that reduce oxidation (here, alpha-tocopherol) in atheromatous plaques. This study paves the way to non-invasive targeted imaging of atherosclerosis and synergistic therapeutic applications.

Nanoemulsion: A Review on Mechanisms for the Transdermal Delivery of Hydrophobic and Hydrophilic Drugs

Nanoemulsions (NEs) are colloidal dispersions of two immiscible liquids, oil and water, in which one is dispersed in the other with the aid of a surfactant/co-surfactant mixture, either forming oil-in-water (o/w) or water-in-oil (w/o) nanodroplets systems, with droplets 20–200 nm in size. NEs are easy to prepare and upscale, and they show high variability in their components. They have proven to be very viable, non-invasive, and cost-effective nanocarriers for the enhanced transdermal delivery of a wide range of active compounds that tend to metabolize heavily or suffer from undesirable side effects when taken orally. In addition, the anti-microbial and anti-viral properties of NE components, leading to preservative-free formulations, make NE a very attractive approach for transdermal drug delivery. This review focuses on how NEs mechanistically deliver both lipophilic and hydrophilic drugs through skin layers to reach the blood stream, exerting the desired therapeutic effect. It highlights the mechanisms and strategies executed to effectively deliver drugs, both with o/w and w/o NE types, through the transdermal way. However, the mechanisms reported in the literature are highly diverse, to the extent that a definite mechanism is not conclusive.

Nanoemulsions in drug delivery: formulation to medical application

Nanoscale oil-in-water emulsions (NEs), heterogeneous systems of two immiscible liquids stabilized by emulsifiers or surfactants, show great potential in medical applications because of their attractive characteristics for drug delivery. NEs have been explored as therapeutic carriers for hydrophobic compounds via various routes of administration. NEs provide opportunities to improve drug delivery via alternative administration routes. However, deep understanding of the NE manufacturing and functionalization fundamentals, and how they relate to the choice of administration route and pharmacological profile is still needed to ease the clinical translation of NEs. Here, we review the diversity of medical applications for NEs and how that governs their formulation, route of administration, and the emergence of increasing sophistication in NE design for specific application.

Characterisation, in-vitro and in-vivo evaluation of valproic acid-loaded nanoemulsion for improved brain bioavailability

OBJECTIVE

This study was aimed to investigate the potential of formulated valproic acid-encapsulated nanoemulsion (VANE) to improve the brain bioavailability of valproic acid (VPA).

METHODS

Valproic acid-encapsulated nanoemulsions were formulated and physically characterised (osmolarity, viscosity, drug content, drug encapsulation efficiency). Further investigations were also conducted to estimate the drug release, cytotoxic profile, in-vitro blood-brain barrier (BBB) permeability, pharmacokinetic parameter and the concentration of VPA and VANE in blood and brain.

KEY FINDINGS

Physical characterisation confirmed that VANE was suitable for parenteral administration. Formulating VPA into nanoemulsion significantly reduced the cytotoxicity of VPA. In-vitro drug permeation suggested that VANEs crossed the BBB as freely as VPA. Pharmacokinetic parameters of VANE-treated rats in plasma and brain showed F3 VANE had a remarkable improvement in AUC, prolongation of half-life and reduction in clearance compared to VPA. Given the same extent of in-vitro BBB permeation of VPA and VANE, the higher bioavailability of VANE in brain was believed to have due to higher concentration of VANE in blood. The brain bioavailability of VPA was improved by prolonging the half-life of VPA by encapsulating it within the nanoemulsion-T80.

CONCLUSIONS

Nanoemulsion containing VPA has alleviated the cytotoxic effect of VPA and improved the plasma and brain bioavailability for parenteral delivery of VPA.

Nanoemulsion: Concepts, development and applications in drug delivery

Nanoemulsions are biphasic dispersion of two immiscible liquids: either water in oil (W/O) or oil in water (O/W) droplets stabilized by an amphiphilic surfactant. These come across as ultrafine dispersions whose differential drug loading; viscoelastic as well as visual properties can cater to a wide range of functionalities including drug delivery. However there is still relatively narrow insight regarding development, manufacturing, fabrication and manipulation of nanoemulsions which primarily stems from the fact that conventional aspects of emulsion formation and stabilization only partially apply to nanoemulsions. This general deficiency sets up the premise for current review. We attempt to explore varying intricacies, excipients, manufacturing techniques and their underlying principles, production conditions, structural dynamics, prevalent destabilization mechanisms, and drug delivery applications of nanoemulsions to spike interest of those contemplating a foray in this field.

Drug delivery and drug targeting with parenteral lipid nanoemulsions - A review

Lipid nanosized emulsions or nanoemulsions (NE) are oil in water dispersions with an oil droplet size of about 200nm. This size of oil droplets dispersed in a continuous water phase is a prerequisite for the parenteral, namely intravenous administration. Many parenteral nutrition and drug emulsions on the market confirm the safe use of NE over years. Parenteral emulsions loaded with APIs (active pharmaceutical ingredients) are considered as drug delivery systems (DDS). DDS focuses on the regulation of the in vivo dynamics, such as absorption, distribution, metabolism, and extended bioavailability, thereby improving the effectiveness and the safety of the drugs. Using an emulsion as a DDS, or through the use of surface diversification of the dispersed oil droplets of emulsions, a targeted increase of the API concentration in some parts of the human body can be achieved. This review focuses on NE similar to the marketed once with no or only low amount of additional surfactants beside the emulsifier from a manufacturing point of view (technique, used raw materials).

Long-circulating lipoprotein-mimic nanoparticles for smart intravenous delivery of a practically-insoluble antineoplastic drug: Development, preliminary safety evaluations and preclinical pharmacokinetic studies

Chlorambucil (CHL) is a water-insoluble antineoplastic drug having a short elimination half-life. It suffers from remarkable differences in pharmacokinetics following oral administration. The current work aimed to assess safety and pharmacokinetics of CHL-loaded, lipoprotein-mimic, nanoparticles (NPs) following intravenous administration. The design of NPs was based on complexation between egg yolk lecithin (EYL) and bovine serum albumin (BSA). The NPs were preliminary evaluated via FT-IR, DSC and P-XRD. The NPs were characterized for particle size, zeta potential, morphology and drug entrapment efficiency (EE%). The best achieved NP dispersion (LP6) and CHL solution were challenged for in vitro hemolytic potential, in vivo vascular irritation studies in rabbits and in vivo pharmacokinetics following intravenous administration in rats. The results confirmed that NPs were stabilized by hydrophobic-attractions and hydrogen-bondings between CHL, BSA and EYL. The amorphous dispersion of CHL within NPs was revealed. LP6 dispersion displayed monodispersed nano-spherical particles (144.33 ± 2.17 nm). It possessed the highest negative zeta potential (-30.55 ± 0.24 mV) and the largest EE% (86.35 ± 2.33%). The significantly (P < 0.05) prolonged MRT(0-∞), longer elimination t50% and reduced plasma clearance highlighted the long-circulating characteristics of LP6. The preliminary safety evaluations and the seven-fold increase in bioavailability elucidated potentiality for smart intravenous delivery of CHL.

EGFR Targeted Theranostic Nanoemulsion for Image-Guided Ovarian Cancer Therapy

PURPOSE

Platinum-based therapies are the first line treatments for most types of cancer including ovarian cancer. However, their use is associated with dose-limiting toxicities and resistance. We report initial translational studies of a theranostic nanoemulsion loaded with a cisplatin derivative, myrisplatin and pro-apoptotic agent, C6-ceramide.

METHODS

The surface of the nanoemulsion is annotated with an endothelial growth factor receptor (EGFR) binding peptide to improve targeting ability and gadolinium to provide diagnostic capability for image-guided therapy of EGFR overexpressing ovarian cancers. A high shear microfludization process was employed to produce the formulation with particle size below 150 nm.

RESULTS

Pharmacokinetic study showed a prolonged blood platinum and gadolinium levels with nanoemulsions in nu/nu mice. The theranostic nanoemulsions also exhibited less toxicity and enhanced the survival time of mice as compared to an equivalent cisplatin treatment.

CONCLUSIONS

Magnetic resonance imaging (MRI) studies indicate the theranostic nanoemulsions were effective contrast agents and could be used to track accumulation in a tumor. The MRI study additionally indicate that significantly more EGFR-targeted theranostic nanoemulsion accumulated in a tumor than non-targeted nanoemulsuion providing the feasibility of using a targeted theranostic agent in conjunction with MRI to image disease loci and quantify the disease progression.

Optimizing nanomedicine pharmacokinetics using physiologically based pharmacokinetics modelling

The delivery of therapeutic agents is characterized by numerous challenges including poor absorption, low penetration in target tissues and non-specific dissemination in organs, leading to toxicity or poor drug exposure. Several nanomedicine strategies have emerged as an advanced approach to enhance drug delivery and improve the treatment of several diseases. Numerous processes mediate the pharmacokinetics of nanoformulations, with the absorption, distribution, metabolism and elimination (ADME) being poorly understood and often differing substantially from traditional formulations. Understanding how nanoformulation composition and physicochemical properties influence drug distribution in the human body is of central importance when developing future treatment strategies. A helpful pharmacological tool to simulate the distribution of nanoformulations is represented by physiologically based pharmacokinetics (PBPK) modelling, which integrates system data describing a population of interest with drug/nanoparticle in vitro data through a mathematical description of ADME. The application of PBPK models for nanomedicine is in its infancy and characterized by several challenges. The integration of property-distribution relationships in PBPK models may benefit nanomedicine research, giving opportunities for innovative development of nanotechnologies. PBPK modelling has the potential to improve our understanding of the mechanisms underpinning nanoformulation disposition and allow for more rapid and accurate determination of their kinetics. This review provides an overview of the current knowledge of nanomedicine distribution and the use of PBPK modelling in the characterization of nanoformulations with optimal pharmacokinetics.

Nanoemulsions in translational research-opportunities and challenges in targeted cancer therapy

Nanoemulsion dosage form serves as a vehicle for the delivery of active pharmaceutical ingredients and has attracted great attention in drug delivery and pharmacotherapy. In particular, nanoemulsions act as an excellent vehicle for poorly aqueous soluble drugs, which are otherwise difficult to formulate in conventional dosage forms. Nanoemulsions are submicron emulsions composed of generally regarded as safe grade excipients. Particle size at the nanoscale and larger surface area lead to some very interesting physical properties that can be exploited to overcome anatomical and physiological barriers associated in drug delivery to the complex diseases such as cancer. Along these lines, nanoemulsions have been engineered with specific attributes such as size, surface charge, prolonged blood circulation, target specific binding ability, and imaging capability. These attributes can be tuned to assist in delivering drug/imaging agents to the specific site of interest, based on active and passive targeting mechanisms. This review focuses on the current state of nanoemulsions in the translational research and its role in targeted cancer therapy. In addition, the production, physico-chemical characterization, and regulatory aspects of nanoemulsion are addressed.

Development of EGFR-targeted nanoemulsion for imaging and novel platinum therapy of ovarian cancer

PURPOSE

Platinum-based chemotherapy is the treatment of choice for malignant epithelial ovarian cancers, but generalized toxicity and platinum resistance limits its use. Theranostic nanoemulsion with a novel platinum prodrug, myrisplatin, and the pro-apoptotic agent, C6-ceramide, were designed to overcome these limitations.

METHODS

The nanoemulsions, including ones with an EGFR binding peptide and gadolinium, were made using generally regarded as safe grade excipients and a high shear microfluidization process. Efficacy was evaluated in ovarian cancer cells, SKOV3, A2780 and A2780CP.

RESULTS

The nanoemulsion with particle size <150 nm were stable in plasma and parenteral fluids for 24 h. Ovarian cancer cells in vitro efficiently took up the non-targeted and EGFR-targeted nanoemulsions; improved cytotoxicity was observed for the these nanoemulsions with the latter showing a 50-fold drop in the IC50 in SKOV3 cells as compared to cisplatin alone. The addition of gadolinium did not affect cell viability in vitro, but showed relaxation times comparable to Magnevist(®).

CONCLUSION

The myrisplatin/C6-ceramide nanoemulsion synergistically enhanced in vitro cytotoxicity. An EGFR binding peptide addition further increased in vitro cytotoxicity in EGFR positive cancer cells. The diagnostic version showed MR imaging similar to the clinically relevant Magnevist® and may be suitable as a theranostic for ovarian cancer.

Comparative pharmacokinetics and tissue distribution analysis of systemically administered 17-β-estradiol and its metabolites in vivo delivered using a cationic nanoemulsion or a peptide-modified nanoemulsion system for targeting atherosclerosis

The primary objective of this study was to compare the biodistribution and pharmacokinetic profile of 17-β-estradiol (17-βE) on systemic delivery using either the cationic or the CREKA-peptide-modified (Cysteine-Arginine-Glutamic-acid-Lysine-Alanine) omega-3-fatty acid oil containing nanoemulsion system in vivo in the wild type C57BL/6 mice. Higher blood concentrations of 17-βE, higher accumulation in the tissues of interest - heart and aorta, and higher accumulation within the other tissues - liver and kidney was observed on delivering 17-βE using the CREKA-peptide-modified nanoemulsion system (AUClast in plasma - 263.89±21.81min*%/injected dose/ml) as compared to the cationic nanoemulsion (AUClast in plasma - 20.2±1.86min*%/injected dose/ml) and solution form (AUClast in plasma - 44.9±1.24min*%/injected dose/ml) respectively. Both, the cationic nanoemulsion and the CREKA-peptide-modified nanoemulsion showed a higher relative targeting efficiency of 4.57 and 4.86 respectively for 17-βE than the relative targeting efficiency of 1.78 observed with the solution form. In conclusion, since the maximum exposure (highest AUClast for plasma and tissues) for 17-βE was observed with the CREKA-peptide-modified nanoemulsion system, the study shows that CREKA-peptide-modified nanoemulsion system was the most suitable vehicle for systemic delivery of 17-βE in the wild type C57BL/6 mice.

A review of multifunctional nanoemulsion systems to overcome oral and CNS drug delivery barriers

The oral and central nervous systems (CNS) present a unique set of barriers to the delivery of important diagnostic and therapeutic agents. Extensive research over the past few years has enabled a better understanding of these physical and biological barriers based on tight cellular junctions and expression of active transporters and metabolizing enzymes at the luminal surfaces of the gastrointestinal (GI) tract and the blood-brain barrier (BBB). This review focuses on the recent understanding of transport across the GI tract and BBB and the development of nanotechnology-based delivery strategies that can enhance bioavailability of drugs. Multifunctional lipid nanosystems, such as oil-in-water nanoemulsions, that integrate enhancement in permeability, tissue and cell targeting, imaging, and therapeutic functions are especially promising. Based on strategic choice of edible oils, surfactants and additional surface modifiers, and different types of payloads, rationale design of multifunctional nanoemulsions can serve as a safe and effective delivery vehicle across oral and CNS barriers.

Delivery of antiinflammatory nutraceuticals by nanoparticles for the prevention and treatment of cancer

Extensive research within the last two decades has revealed that most chronic illnesses, including cancer, diabetes, and cardiovascular and pulmonary diseases, are mediated through chronic inflammation. Thus, suppressing chronic inflammation has the potential to delay, prevent, and even treat various chronic diseases, including cancer. Various nutraceuticals from fruits, vegetables, vitamins, spices, legumes, and traditional Chinese and Ayurvedic medicine have been shown to safely suppress proinflammatory pathways; however, their low bioavailability in vivo limits their use in preventing and treating cancer. We describe here the potential of nanotechnology to fill this gap. Several nutraceuticals, including curcumin, green tea polyphenols, coenzyme Q, quercetin, thymoquinone and others, have been packaged as nanoparticles and proven to be useful in "nanochemoprevention" and "nano-chemotherapy".