Development and Evaluation of a Novel Drug Delivery: Pluronics/SDS Mixed Micelle Loaded With Myricetin In Vitro and In Vivo

Isoliquiritigenin Containing PH Sensitive Micelles for Enhanced Anti-Colitis Activity

Isoliquiritigenin (ISL) is known to have a variety of pharmacological activities, but its poor water solubility limits its application. In order to improve the bioavailability of ISL and its anti-colitis activity, this study aims to develop an effective drug delivery system loaded with ISL. In this study, ISL pH-sensitive micelles (ISL-M) were prepared by thin film hydration method. The micellar size (PS), polydispersity index (PDI), electrokinetic potential (ζ-potential), drug loading (DL), encapsulation rate (EE) and other physical parameters were characterized. The storage stability of ISL-M was tested, release in vitro and pharmacokinetic studies in rats were performed, and the anti-inflammatory effect of ISL-M on ulcerative colitis induced by dextran sulfate sodium (DSS) was evaluated. The results showed that PS, PDI, ZP, EE% and DL% of ISL-M were 151.15±1.04 nm, 0.092±0.014, -31.32±0.721 mV, 93.97±1.53 % and 8.42±0.34 %, respectively. Compared with unformulated ISL (F-ISL), the cumulative release rate of ISL-M in the three different media was significantly increased and showed a certain pH sensitivity. The area under drug curve (AUC0-t) and peak concentration (Cmax) of ISL-M group were 2.94 and 4.06 times higher than those of ISL group. In addition, ISL-M is expected to develop new methods for increasing the bioavailability and anti-inflammatory activity of ISL.

Layered Double Hydroxides as an Intercalation System for Hydrophobic Molecules

Layered double hydroxides (LDHs) have been extensively studied as drug delivery systems due to their favorable characteristics, including biocompatibility, high loading efficiency, and pH-responsive release. However, the current research predominantly focuses on LDHs as carriers for various anionic drugs, while there are only limited reports on LDHs as carriers for hydrophobic drugs. In this study, we successfully achieved the loading of a hydrophobic drug mimic, Nile red (NR), into LDHs using sodium dodecyl sulfate (SDS) as an intermediate storage medium. Furthermore, we optimized the experimental methods and varied the SDS/NR molar ratio to optimize this intercalation system. With an increase in the SDS/NR molar ratio from 2/1 to 32/1, the loading efficiency of LDH-SDS-NR for NR initially increased from 1.32% for LDH-SDS-NR_2/1 to 4.46% for LDH-SDS-NR_8/1. Then, the loading efficiency slightly decreased to 3.64% for LDH-SDS-NR_16.8/1, but then increased again to 6.31% for LDH-SDS-NR_32/1. We believe that the established method and the obtained results in this study broaden the application scope of LDHs as delivery systems for hydrophobic drugs and contribute to the further expansion of the application scope of LDHs.

Protection against cancer therapy-induced cardiovascular injury by planed-derived polyphenols and nanomaterials

Cancer therapy-induced heart injury is a significant concern for cancer patients undergoing chemotherapy, radiotherapy, immunotherapy, and also targeted molecular therapy. The use of these treatments can lead to oxidative stress and cardiomyocyte damage in the heart, which can result in heart failure and other cardiac complications. Experimental studies have revealed that chemotherapy drugs such as doxorubicin and cyclophosphamide can cause severe side effects such as cardiac fibrosis, electrophysiological remodeling, chronic oxidative stress and inflammation, etc., which may increase risk of cardiac disorders and attacks for patients that underwent chemotherapy. Similar consequences may also be observed for patients that undergo radiotherapy for left breast or lung malignancies. Polyphenols, a group of natural compounds with antioxidant and anti-inflammatory properties, have shown the potential in protecting against cancer therapy-induced heart injury. These compounds have been found to reduce oxidative stress, necrosis and apoptosis in the heart, thereby preserving cardiac function. In recent years, nanoparticles loaded with polyphenols have also provided for the delivery of these compounds and increasing their efficacy in different organs. These nanoparticles can improve the bioavailability and efficacy of polyphenols while minimizing their toxicity. This review article summarizes the current understanding of the protective effects of polyphenols and nanoparticles loaded with polyphenols against cancer therapy-induced heart injury. The article discusses the mechanisms by which polyphenols protect the heart, including antioxidant and anti-inflammation abilities. The article also highlights the potential benefits of using nanoparticles for the delivery of polyphenols.

Surfactant and Block Copolymer Nanostructures: From Design and Development to Nanomedicine Preclinical Studies

The medical application of nanotechnology in the field of drug delivery has so far exhibited many efforts in treating simple to extremely complicated and life-threatening human conditions, with multiple products already existing in the market. A plethora of innovative drug delivery carriers, using polymers, surfactants and the combination of the above, have been developed and tested pre-clinically, offering great advantages in terms of targeted drug delivery, low toxicity and immune system activation, cellular biomimicry and enhanced pharmacokinetic properties. Furthermore, such artificial systems can be tailor-made with respect to each therapeutic protocol and disease type falling under the scope of personalized medicine. The simultaneous delivery of multiple therapeutic entities of different nature, such as genes and drugs, can be achieved, while novel technologies can offer systems with multiple modalities often combining therapy with diagnosis. In this review, we present prominent, innovative and state-of-the-art scientific efforts on the applications of surfactant-based, polymer-based, and mixed surfactant-polymer nanoparticle drug formulations intended for use in the medical field and in drug delivery. The materials used, formulation steps, nature, properties, physicochemical characteristics, characterization techniques and pharmacokinetic behavior of those systems, are presented extensively in the length of this work. The material presented is focused on research projects that are currently in the developmental, pre-clinical stage.

Pharmacodynamic Material Basis and Potential Mechanism Study of Spatholobi Caulis in Reversing Osteoporosis

Objective

To elucidate the mechanism of Spatholobi Caulis (SC) in treating osteoporosis (OP) integrated zebrafish model and bioinformatics.

Methods

Skeleton staining coupled with image quantification was performed to evaluate the effects of SC on skeleton mineralization area (SSA) and total optical density (TOD). Zebrafish locomotor activity was monitored using the EthoVision XT. Bioactive compounds of SC and their corresponding protein targets were acquired from Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. Potential therapeutic targets for OP were summarized through retrieving 5 databases, and then, the overlapping genes between SC and OP were acquired. The core genes were selected by CytoHubba. Subsequently, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) functional analysis of the intersection target genes were carried out by R software. Finally, the molecular docking simulation was manipulated between the ingredients and the hub genes.

Results

Compared with the model group, SC significantly increased the SSA and TOD at 10 mg/mL and improved the locomotor activity in a dose-dependent manner (p < 0.001). 33 components of SC were associated with 72 OP-related genes including 10 core genes (MAPK1, VEGFA, MMP9, AKT1, AR, IL6, CALM3, TP53, EGFR, and CAT). Advanced Glycation End Product (AGE) Receptor for AGE (RAGE) signaling pathway was screened out as the principal pathway of SC in anti-OP. The bioactive components (Aloe-emodin, Emodin, Formononetin, Licochalcone A, Luteolin, and Lopac-I-3766) have excellent affinity to core genes (MAPK1, VEGFA, MMP9, AKT1, and IL6).

Conclusion

SC had the hierarchical network characteristics of "multicomponents/multitargets/multifunctions/multipathways" in reversing OP, but AGE-RAGE signaling pathway may be the main regulatory mechanism.

Nickel Nanoparticles: Applications and Antimicrobial Role against Methicillin-Resistant Staphylococcus aureus Infections

Methicillin-resistant Staphylococcus aureus (MRSA) has evolved vast antibiotic resistance. These strains contain numerous virulence factors facilitating the development of severe infections. Considering the costs, side effects, and time duration needed for the synthesis of novel drugs, seeking efficient alternative approaches for the eradication of drug-resistant bacterial agents seems to be an unmet requirement. Nickel nanoparticles (NiNPs) have been applied as prognostic and therapeutic cheap agents to various aspects of biomedical sciences. Their antibacterial effects are exerted via the disruption of the cell membrane, the deformation of proteins, and the inhibition of DNA replication. NiNPs proper traits include high-level chemical stability and binding affinity, ferromagnetic properties, ecofriendliness, and cost-effectiveness. They have outlined pleomorphic and cubic structures. The combined application of NiNPs with CuO, ZnO, and CdO has enhanced their anti-MRSA effects. The NiNPs at an approximate size of around 50 nm have exerted efficient anti-MRSA effects, particularly at higher concentrations. NiNPs have conferred higher antibacterial effects against MRSA than other nosocomial bacterial pathogens. The application of green synthesis and low-cost materials such as albumin and chitosan enhance the efficacy of NPs for therapeutic purposes.

Flavonoids: Food associations, therapeutic mechanisms, metabolism and nanoformulations

Flavonoids possess an impressive therapeutic potential, thereby imparting them a nutraceutical character. As it becomes increasingly common to consume foods associated with healing properties, it is imperative to understand the associations of different foods with different classes of nutraceutic compounds, and their mechanisms of therapeutic action. At the same time, it is important to address the limitations thereof so that plausible future directions may be drawn. This review summarizes the food associations of flavonoids, and discusses the mechanisms responsible for imparting them their nutraceutic properties, detailing the nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathway, inhibition of inflammatory signaling pathways such as toll-like receptor (TLR), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), cyclooxygenase 2 (COX-2) and lipoxygenase-2 (LOX-2) mediators. Further on, the review explains the mechanism of flavonoids metabolism, reasons for low bioavailability and thereafter recapitulates the role of technological interventions to overcome the limitations, with a particular focus on nanoformulations that utilize the synergy between flavonoids and biocompatible materials used as nanocarriers, as reported in works spanning over a decade. It is the Generally Recognized as Safe (GRAS) classified carriers that will become the basis for developing functional formulations. It is promisingly noteworthy that some flavonoid formulations have been commercialized and mentioned therein. Such commercially viable and safe for consumption technological applications pave way for bringing science to the table, and add value to the innate properties of flavonoids.

Technologies for Solubility, Dissolution and Permeation Enhancement of Natural Compounds

The current review is based on the advancements in the field of natural therapeutic agents which could be utilized for a variety of biomedical applications and against various diseases and ailments. In addition, several obstacles have to be circumvented to achieve the desired therapeutic effectiveness, among which limited dissolution and/or solubility and permeability are included. To counteract these issues, several advancements in the field of natural therapeutic substances needed to be addressed. Therefore, in this review, the possible techniques for the dissolution/solubility and permeability improvements have been addressed which could enhance the dissolution and permeability up to several times. In addition, the conventional and modern isolation and purification techniques have been emphasized to achieve the isolation and purification of single or multiple therapeutic constituents with convenience and smarter approaches. Moreover, a brief overview of advanced natural compounds with multiple therapeutic effectiveness have also been anticipated. In brief, enough advancements have been carried out to achieve safe, effective and economic use of natural medicinal agents with improved stability, handling and storage.

Study on the Effect of Polymer Excipients on the Dispersibility, Interaction, Solubility, and Scavenging Reactive Oxygen Species of Myricetin Solid Dispersion: Experiment and Molecular Simulation

Although the preparation of amorphous solid dispersions can improve the solubility of crystalline drugs, there is still a lack of guidance on the micromechanism in the screening and evaluation of polymer excipients. In this study, a particular method of experimental characterization combined with molecular simulation was attempted on solubilization of myricetin (MYR) by solid dispersion. According to the analysis of the dispersibility and hydrogen-bond interaction, the effectiveness of the solid dispersion and the predicted sequence of poly(vinyl pyrrolidone) (PVP) > hypromellose (HPMC) > poly(ethylene glycol) (PEG) as the polymer excipient were verified. Through the dissolution, cell viability, and reactive oxygen species (ROS)-level detection, the reliability of simulation and micromechanism analysis was further confirmed. This work not only provided the theoretical guidance and screening basis for the miscibility of solid dispersions from the microscopic level but also served as a reference for the modification of new drugs.

Improving oral bioavailability of medicinal herbal compounds through lipid-based formulations - A Scoping Review

BACKGROUND

Although numerous medicinal herbal compounds demonstrate promising therapeutic potential, their clinical application is often limited by their poor oral bioavailability. To circumvent this barrier, various lipid-based herbal formulations have been developed and trialled with promising experimental results.

PURPOSE

This scoping review aims to describe the effect of lipid-based formulations on the oral bioavailability of herbal compounds.

METHODS

A systematic search was conducted across three electronic databases (Medline, Embase and Cochrane Library) between January 2010 and January 2021 to identify relevant studies. The articles were rigorously screened for eligibility. Data from eligible studies were then extracted and collated for synthesis and descriptive analysis using Covidence.

RESULTS

A total of 109 studies were included in the present review: 105 animal studies and four clinical trials. Among the formulations investigated, 50% were emulsions, 34% lipid particulate systems, 12% vesicular systems, and 4% were other types of lipid-based formulations. Within the emulsion system classification, self-emulsifying drug delivery systems were observed to produce the best improvements in oral bioavailability, followed by mixed micellar formulations. The introduction of composite lipid-based formulations and the use of uncommon surfactants such as sodium oleate in emulsion preparation was shown to consistently enhance the bioavailability of herbal compounds with poor oral absorption. Interestingly, the lipid-based formulations of magnesium lithospermate B and Pulsatilla chinensis produced an absolute bioavailability greater than 100% indicating the possibility of prolonged systemic circulation. With respect to chemical conjugation, D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) was the most frequently used and significantly improved the bioavailability of its phytoconstituents.

CONCLUSION

Our findings suggest that there is no distinct lipid-based formulation superior to the other. Bioavailability improvements were largely dependent on the nature of the phytoconstituents. This scoping review, however, provided a detailed summary of the most up-to-date evidence on phytoconstituents formulated into lipid preparations and their oral bioavailability. We conclude that a systematic review and meta-analysis between bioavailability improvements of individual phytoconstituents (such as kaempferol, morin and myricetin) in various lipid-based formulations will provide a more detailed association. Such a review will be highly beneficial for both researchers and herbal manufacturers.

Improved oral bioavailability, cellular uptake, and cytotoxic activity of zingerone via nano-micelles drug delivery system

Herein, a nano-micelle drug delivery system was developed to orally improved zingerone's bioavailability and its antitumor effect. Indeed, zingerone-loaded d-α-tocopheryl polyethylene glycol succinate micelles (ZTMs) were effectively prepared, characterised and assessed. The ZTMs had diameter, polydispersity index, and zeta potential of 50.62 ± 0.25 nm, 0.168 ± 0.006, and -28.07 ± 0.33 mV, respectively, coupled with a high entrapment efficiency (m/m, %) were 94.71 ± 2.02. The release rate of ZTMs in three media was significantly greater than that of free zingerone. Intriguingly, results obtained from pharmacokinetic studies showed that the oral bioavailability of the ZTMs was enhanced by 5.10 times in comparison with the free zingerone. Further, the half inhibitory concentration (IC50) of ZTMs and free zingerone was 7.56 μg/ml and 14.30 μg/ml, respectively, on HepG2 cells. Hence, ZTMs may be used as a potential approach to enrich the solubility, bioavailability, and concomitant anti-proliferative effect of zingerone in vitro.

Rheumatoid arthritis treatment using hydroxychloroquine and methotrexate co-loaded nanomicelles: In vivo results

Rheumatoid arthritis (RA) is the most common inflammatory rheumatic disease, affecting almost 1% of the world population. It is a long-lasting autoimmune disease, which mainly affects the joints causing inflammation and swelling of the synovial joint. RA has a significant impact on the ability to perform daily activities including simple work and household chores. Nonetheless, due to the long periods of pain and the continuous use of anti-inflammatory drugs, RA can debilitate the quality of life and increases mortality. Current therapeutic approaches to treat RA aim to achieve prolonged activity and early and persistent remission of the disease, with the gradual adoption of different drugs available. In this study, we developed a novel hydroxychloroquine and methotrexate co-loaded Pluronic® F-127 nanomicelle and evaluated its therapeutic effects against RA. Our results showed that drug-loaded nanomicelles were capable of modulating the inflammatory process of RA and reducing osteoclastogenesis, edema, and cell migration to the joint. Overall, compared to the free drugs, the drug-loaded nanomicelles showed a 2-fold higher therapeutic effect.

Surface-Induced Crystallization of Sodium Dodecyl Sulfate (SDS) Micellar Solutions in Confinement

We investigate the role of confinement on the onset of crystallization in subcooled micellar solutions of sodium dodecyl sulfate (SDS), examining the impact of sample volume, substrate surface energy, and surface roughness. Using small angle neutron scattering (SANS) and dynamic light scattering (DLS), we measure the crystallization temperature upon cooling and the metastable zone width (MSZW) for bulk 10-30 wt% SDS solutions. We then introduce a microdroplet approach to quantify the impact of surface free energy (18-65 mN/m) and substrate roughness (R_α ≃ 0-60 μm) on the kinetics of surface-induced crystallization through measurements of induction time (t_i) under isothermal conditions. While t_i is found to decrease exponentially with decreasing temperature (increasing subcooling) for all tested surfaces, increasing the surface energy could cause a significant further reduction of up to ∼40 fold. For substrates with the lowest surface energy and longest t_i, microscale surface roughness is found to enhance crystal nucleation, in particular for R_α ≥ 10 μm. Finally, we demonstrate that tuning the surface energy and microscopic roughness can be effective routes to promote or delay nucleation in bulk-like volumes, thus greatly impacting the stability of surfactant solutions at lower temperatures.

Improved oral bioavailability and anti-chronic renal failure activity of chrysophanol via mixed polymeric micelles

AIMS

This study was designed to prepare chrysophanol-loaded micelles (CLM) to improve the oral bioavailability, targetability and anti-chronic renal failure (CRF) activity of chrysophanol (CH).

METHODS

The preparation of CLM was achieved via thin-film dispersion technique. The in vitro release of CLM compared with free CH was measured in phosphate buffer solution (PBS) containing 0.5%w/v sodium dodecyl sulphate (pH 6.8) while the pharmacokinetic and anti-CRF activity study was also conducted in rats. Moreover, the tissue distribution of CLM was investigated in the mice.

RESULTS

The CLM had particle size (PS) of 29.64 ± 0.71 nm, and encapsulation efficiency (EE) of 90.48 ± 1.22%w/w. The cumulative release rate of CH from the micellar system was significantly higher than that of the free CH (86%m/m vs. 15%m/m, p < 0.01). In vivo pharmacokinetic studies showed that the bioavailability of CLM after oral administration was substantially improved (about 3.4 times) compared with free drugs (p < 0.01). Also, it was observed that CLM accumulated well in the liver and brain. Moreover, in vitro renal podocytes study showed that CLM had better protection against renal podocyte damage than the free CH. In addition, CLM significantly (p < 0.01) reduced levels of blood urea nitrogen (BUN), kidney injury molecule-1 (Kim-1), and serum creatinine (SCr), which obviously improved kidney damage in rats with CRF.

CONCLUSIONS

Collectively, these findings suggest that mixed micelles may be used as a promising drug delivery system for oral bioavailability improvement and concomitantly enhance the anti-CRF activity of CH, as well as provide a basis for the clinical application of CH.

Magnetic nanoemulsions as candidates for Alzheimer's disease dual imaging theranostics

Alzheimer's disease (AD) is the most prevalent cause of dementia linked to the accumulation of amyloid-beta (Aβ) plaques-fibrils that impair cognitive functions. Magnetic nanoparticles (MNPs) are emerging as promising tools for the crusade against AD owning to appropriate biocompatibility and facile functionalization that can lead to theranostic agents. Herein, the fabrication of a multimodal (magnetic resonance imaging (MRI), fluorescence imaging, and drug carrier) magnetic nanoemulsion (MNE) is reported as an AD theranostic candidate. Initially zinc ferrite MNPs of high saturation magnetization (129 emu g^-1) were synthesized through a modified microwave-assisted polyol process. Memantine (a registered AD drug) was labeled with fluorescein (Mem-Flu) and encapsulated with the MNPs in sodium dodecyl sulfate micelles to form the MNE. Small hydrodynamic size (107), high encapsulation (77.5%) and loading efficiencies (86.1%) and sufficient transverse relaxivity (48.7 mM^-1 s^-1) were achieved through the design while sustained release of Mem-Flu was unveiled by in zero-order, first-order, Higuchi and Korsmeyer-Peppas pharmacokinetic models. Moreover, the MNE acquired fluorescence imaging ability of Aβ_1-42 peptide monomers and/or plaques-fibrils via the fluorescein labeling of Memantine. A novel inorganic-organic hybrid multimodal AD theranostic candidate is presented.

Promoted Antitumor Activity of Myricetin against Lung Carcinoma Via Nanoencapsulated Phospholipid Complex in Respirable Microparticles

PURPOSE

Myricetin (MYR) flavonoid is well-recognized for its antioxidant, anti-inflammatory and anti-tumor potential. Introducing nanomedicine was the ultimate resort to solve the imperfections of this nutraceutical, namely solubility, stability and delivery issues. The study, thus, aims at developing inhalable microparticles comprising MYR solid lipid nanoparticles (SLNs) for lung cancer therapy.

METHODS

A two-step preparation procedure starting with complexation of MYR with the phospholipid Lipoid-S100, followed by nanoencapsulation in Gelucire-based, surfactant-free SLNs was developed. SLNs were characterized in terms of physicochemical properties, MYR loading, release behavior as well as anti-tumor potential and cellular uptake. Respirable microparticles were then obtained by spray drying SLNs with carbohydrate carriers. Their size, flowability and pulmonary deposition pattern were assessed.

RESULTS

Optimized SLNs were 75.98 nm in diameter with a zeta-potential of -22.5 mV, and an encapsulation efficiency of 84.5%. Attempts to ameliorate drug loading implicate MYR-phospholipid complexation (MYR-PH-CPX) prior to its entrapment in SLNs, which ensured 5-fold increase in drug loading. Viability assays were modified to guarantee MYR chemical stability. Superior antitumor activity of MYR-phospholipid-complex and 3-fold reduction in IC₅₀ were accomplished with MYR-SLNs. This could be related to enhanced cellular uptake revealed by confocal imaging and doubled fluorescence intensity. SLNs entrapping MYR-PH-CPX were spray-dried with carbohydrate carriers to produce respirable microparticles. The latter ensured MMAD of 2.39 μm and span index of 1.84, in addition to good flowability and > 80% release over 8 h. Deposition experiments revealed MMAD of 2.77 μm, FPF of 81.23 and EF of 93% indicating particle deposition in the targeted bronchial region.

CONCLUSIONS

The study highlights the ability of phospholipid-complex on the nanoencapsulation, cellular uptake and antitumor activity of MYR. Formulation of respirable microparticles gives promises of efficacious therapy of lung carcinoma.

Self-Microemulsifying Drug Delivery System for Improved Oral Delivery and Hypnotic Efficacy of Ferulic Acid

Purpose

Ferulic acid (FA) is a natural compound which is used to treat insomnia. However, its use is limited because of its poor oral bioavailability caused by extremely rapid elimination. The current study aimed to develop a self-microemulsifying drug delivery system (SMEDDS) to improve the oral delivery of FA and to enhance its hypnotic efficacy.

Methods

FA-SMEDDS was prepared, and its morphology and storage stability were characterized. The formulation was also subjected to pharmacokinetic and tissue distribution studies in rats. The hypnotic efficacy of FA-SMEDDS was evaluated in p-chlorophenylalanine-induced insomnia mice.

Results

FA-loaded SMEDDS exhibited a small droplet size (15.24 nm) and good stability. Oral administration of FA-SMEDDS yielded relative bioavailability of 185.96%. In the kidney, SMEDDS decreased the distribution percentage of FA from 76.1% to 59.4% and significantly reduced its metabolic conversion, indicating a reduction in renal elimination. Interestingly, FA-SMEDDS showed a higher distribution in the brain and enhanced serotonin levels in the brain, which extended the sleep time by 2-fold in insomnia mice.

Conclusion

This is the first study to show that FA-loaded SMEDDS decreased renal elimination, enhanced oral bioavailability, increased brain distribution, and improved hypnotic efficacy. Thus, we have demonstrated that SMEDDS is a promising carrier which can be employed to improve the oral delivery of FA and facilitate product development for the therapy of insomnia.

WS2 nanosheets functionalized by biomimetic lipids with enhanced dispersibility for photothermal and chemo combination therapy

A WS₂-lipid nanocarrier with enhanced stability and intratumoral accumulation was synthesized for photothermal-chemo combination therapy

Hydrophobically Modified Glucan as an Amphiphilic Carbohydrate Polymer for Micellar Delivery of Myricetin

Myricetin (Myr) is a phytochemical with many functional properties. However, its hydrophobicity, low bioavailability, and stability limit its application. In this study, octadecanoate oat β-glucan (OGE) was synthesized and gained recognition as a self-assembled micelle forming a polymer with a critical micelle concentration (CMC) of 59.4 μg/mL. The Myr-loaded OGE micelle was then prepared and characterized by dynamic light scattering (DLS), transmission electron microscope (TEM), X-ray diffractometer (XRD), and Fourier-transform infrared spectroscopy (FT-IR) spectra. The water solubility of Myr was greatly enhanced by forming the Myr/OGE inclusion complex. Consequently, compared to free Myr, the retention of Myr in Myr-loaded OGE micelle was effectively increased during the intestinal digestion phase, and its antioxidant activity was also improved. Overall, our findings demonstrated the potential applications of OGE polymer for the development of prospective micelle in health food, cosmetics, and pharmaceutical fields because they can aid in the delivery of hydrophobic functional compounds like Myr.

Myricetin nanoliposomes induced SIRT3-mediated glycolytic metabolism leading to glioblastoma cell death

As the most aggressive and malignant glioma, glioblastoma multiforme (GBM) abnormally expresses genes that mediate glycolytic metabolism and tumour cell growth. In this study, we investigated myricetin incorporated nanoliposomes and ascertained their prospect in effectively treating cancer via the employment of the GBM cell line DBTRG-05MG. Notably, the myricetin nanoliposomes (MYR-NLs) displayed potent inhibition of proliferation and significantly regulated the levels of proteins related to both glycolytic metabolism and cell survival. Most importantly, SIRT3 and phosphorylated p53 were also down-regulated by MYR-NLs, indicating that the MYR-NLs inhibited GBM cell growth through the SIRT3/p53-mediated PI3K/Akt-ERK and mitochondrial pathways. Our findings thus provide rational evidence that liposomal myricetin targeted at alternative cell death pathways may be a useful adjuvant therapy in glioblastoma treatment.

Designing of fatty acid-surfactant conjugate based nanomicelles of morin hydrate for simultaneously enhancing anticancer activity and oral bioavailability

Morin hydrate (MH) is a naturally occurring polyphenolic flavonol compound. It has been recently investigated for its many biological activities such as anti-inflammatory, anticancer, antioxidant, antiarthritic, antifertility, antiplasmodic and anticancer. Though these outcomes are very promising, its low aqueous solubility and oral bioavailability restrict its clinical uses. Therefore, in this study we report pluronic F68 and stearic acid conjugated (F68-SA) nanomicelles for increasing oral bioavailability of MH. The MH loaded F68-SA nanomicelles (MHNM) were prepared by the solvent evaporation method. The MHNM were extensively characterized for the size, surface charge, stability, morphology, critical micelle concentration, drug content, and in-vitro drug release. The cell viability assay depicted a significant increase in cytotoxicity of MH against A549 human lung cancer cells after incubating as MHNM. Exposure of A549 cells to MHNM induced cell apoptosis in the cells as observed in apoptosis studies. Pharmacokinetic studies in Sprague-Dawley rats revealed that MHNM significantly increased the oral bioavailability of MH as compared to pure drug. Therefore, the novel, surfactant-lipid based micellar system is an effective solubilizing and delivering system for oral administration of poorly water soluble drugs like MH.

Self-assembled biodegradable polymeric micelles to improve dapoxetine delivery across the blood-brain barrier

Background

Dapoxetine (DPX) is the drug of choice for the specific treatment of premature ejaculation. DPX is characterized by relatively low bioavailability (42%) and short half-life (1.5 h). The aim of this study was to improve DPX bioavailability and delivery across the blood–brain barrier (BBB) using a nanostructured DPX formulation for improved DPX efficacy and patient satisfaction.

Materials and methods

DPX-loaded polymeric micelles (PMs) formulations (F1–F3) were characterized for particle sizes, entrapment efficiencies, and Fourier transform infrared spectroscopic and transmission electron microscopic evaluations. In addition, diffusion profiles of the prepared formulations were investigated. Animal model pharmacokinetic parameters in plasma and brain tissues were investigated and compared with commercial DPX tablets.

Results

Particle size analysis revealed that formulations of DPX PMs showed a narrow range of 62.7±9.3–45.45±9.1 nm for F1–F3. In addition, DPX PMs showed a sustained release pattern with 91.27%±7.64%, 79.43%±7.81%, and 63.78%±5.05% of DPX content permeated after 24 h for F1, F2, and F3, respectively. Plasma pharmacokinetic parameters for DPX PMs showed significant increase (P<0.05) for the area under drug concentration–time curves in plasma and brain tissues compared with commercial DPX tablets.

Conclusion

DPX formulations in the form of PMs improved bioavailability and efficacy across the BBB. This DPX formulation provided improved brain delivery in order to enhance the convenience and compliance of patients.

Crossing the Blood-Brain Barrier: Recent Advances in Drug Delivery to the Brain

CNS disorders are on the rise despite advancements in our understanding of their pathophysiological mechanisms. A major hurdle to the treatment of these disorders is the blood-brain barrier (BBB), which serves as an arduous janitor to protect the brain. Many drugs are being discovered for CNS disorders, which, however fail to enter the market because of their inability to cross the BBB. This is a pronounced challenge for the pharmaceutical fraternity. Hence, in addition to the discovery of novel entities and drug candidates, scientists are also developing new formulations of existing drugs for brain targeting. Several approaches have been investigated to allow therapeutics to cross the BBB. As the molecular structure of the BBB is better elucidated, several key approaches for brain targeting include physiological transport mechanisms such as adsorptive-mediated transcytosis, inhibition of active efflux pumps, receptor-mediated transport, cell-mediated endocytosis, and the use of peptide vectors. Drug-delivery approaches comprise delivery from microspheres, biodegradable wafers, and colloidal drug-carrier systems (e.g., liposomes, nanoparticles, nanogels, dendrimers, micelles, nanoemulsions, polymersomes, exosomes, and quantum dots). The current review discusses the latest advancements in these approaches, with a major focus on articles published in 2015 and 2016. In addition, we also cover the alternative delivery routes, such as intranasal and convection-enhanced diffusion methods, and disruption of the BBB for brain targeting.

Pluronic-based micelle encapsulation potentiates myricetin-induced cytotoxicity in human glioblastoma cells

As one of the natural herbal flavonoids, myricetin has attracted much research interest, mainly owing to its remarkable anticancer properties and negligible side effects. It holds great potential to be developed as an ideal anticancer drug through improving its bioavailability. This study was performed to investigate the effects of Pluronic-based micelle encapsulation on myricetin-induced cytotoxicity and the mechanisms underlying its anticancer properties in human glioblastoma cells. Cell viability was assessed using a methylthiazol tetrazolium assay and a real-time cell analyzer. Immunoblotting and quantitative reverse transcriptase polymerase chain reaction techniques were used for determining the expression levels of related molecules in protein and mRNA. The results indicated that myricetin-induced cytotoxicity was highly potentiated by the encapsulation of myricetin. Mitochondrial apoptotic pathway was demonstrated to be involved in myricetin-induced glioblastoma cell death. The epidermal growth factor receptor (EGFR)/PI3K/Akt pathway located in the plasma membrane and cytosol and the RAS-ERK pathway located in mitochondria served as upstream and downstream targets, respectively, in myricetin-induced apoptosis. MiR-21 inhibitors interrupted the expression of EGFR, p-Akt, and K-Ras in the same fashion as myricetin-loaded mixed micelles (MYR-MCs) and miR-21 expression were dose-dependently inhibited by MYR-MCs, indicating the interaction of miR-21 with MYR-MCs. This study provided evidence supportive of further development of MYR-MC formulation for preferentially targeting mitochondria of glioblastoma cells.

Multifunctional theranostic Pluronic mixed micelles improve targeted photoactivity of Verteporfin in cancer cells

Nanotechnology development provides new strategies to treat cancer by integration of different treatment modalities in a single multifunctional nanoparticle. In this scenario, we applied the multifunctional Pluronic P123/F127 mixed micelles for Verteporfin-mediated photodynamic therapy in PC3 and MCF-7 cancer cells. Micelles functionalization aimed the targeted delivery by the insertion of biotin moiety on micelle surface and fluorescence image-based through rhodamine-B dye conjugation in the polymer chains. Multifunctional Pluronics formed spherical nanoparticulated micelles that efficiently encapsulated the photosensitizer Verteporfin maintaining its favorable photophysical properties. Lyophilized formulations were stable at least for 6months and readily reconstituted in aqueous media. The multifunctional micelles were stable in protein-rich media due to the dual Pluronic mixed micelles characteristic: high drug loading capacity provided by its micellar core and high kinetic stability due its biocompatible shell. Biotin surface functionalized micelles showed higher internalization rates due biotin-mediated endocytosis, as demonstrated by competitive cellular uptake studies. Rhodamine B-tagged micelles allowed monitoring cellular uptake and intracellular distribution of the formulations. Confocal microscopy studies demonstrated a larger intracellular distribution of the formulation and photosensitizer, which could drive Verteporfin to act on multiple cell sites. Formulations were not toxic in the dark condition, but showed high Verteporfin-induced phototoxicity against both cancer cell lines at low drug and light doses. These results point Verteporfin-loaded multifunctional micelles as a promising tool to further developments in photodynamic therapy of cancer.