Juglone loaded poloxamer 188/phospholipid mixed micelles evaluated in vitro and in vivo in breast cancer

Unlocking the potential of 1,4-naphthoquinones: A comprehensive review of their anticancer properties

Cancer encompasses a group of pathologies with common characteristics, high incidence, and prevalence in all countries. Although there are treatments available for this disease, they are not always effective or safe, often failing to achieve the desired results. This is why it is necessary to continue the search for new therapies. One of the strategies for obtaining new antitumor drugs is the use of 1,4-naphthoquinone as a scaffold in synthetic or natural products with antitumor activity. This review focuses on compiling studies related to the antitumor activity of 1,4-naphthoquinone and its natural and synthetic derivatives over the last 10 years. The work describes the main natural naphthoquinones with antitumor activity and classifies the synthetic naphthoquinones based on the structural modifications made to the scaffold. Additionally, the formation of metal complexes using naphthoquinones as a ligand is considered. After a thorough review, 197 synthetic compounds with potent biological activity against cancer have been classified according to their chemical structures and their mechanisms of action have been described.

Proline Isomerization: From the Chemistry and Biology to Therapeutic Opportunities

Proline isomerization, the process of interconversion between the cis- and trans-forms of proline, is an important and unique post-translational modification that can affect protein folding and conformations, and ultimately regulate protein functions and biological pathways. Although impactful, the importance and prevalence of proline isomerization as a regulation mechanism in biological systems have not been fully understood or recognized. Aiming to fill gaps and bring new awareness, we attempt to provide a wholistic review on proline isomerization that firstly covers what proline isomerization is and the basic chemistry behind it. In this section, we vividly show that the cause of the unique ability of proline to adopt both cis- and trans-conformations in significant abundance is rooted from the steric hindrance of these two forms being similar, which is different from that in linear residues. We then discuss how proline isomerization was discovered historically followed by an introduction to all three types of proline isomerases and how proline isomerization plays a role in various cellular responses, such as cell cycle regulation, DNA damage repair, T-cell activation, and ion channel gating. We then explore various human diseases that have been linked to the dysregulation of proline isomerization. Finally, we wrap up with the current stage of various inhibitors developed to target proline isomerases as a strategy for therapeutic development.

Juglone Inhibits Listeria monocytogenes ATCC 19115 by Targeting Cell Membrane and Protein

Foodborne disease caused by Listeria monocytogenes is a major global food safety problem. A potential solution is the antimicrobial development of the highly bioactive natural product juglone, yet few studies exist on its antibacterial mechanism against L. monocytogenes. Thus, we aimed to elucidate the antibacterial mechanism of action of juglone against L. monocytogenes by determining the resultant cell morphology, membrane permeability, membrane integrity, and proteome changes. The minimum inhibitory concentration of juglone against L. monocytogenes was 50 μg/mL, and L. monocytogenes treated with juglone had longer lag phases compared to controls. Juglone induced L. monocytogenes cell dysfunction, leakage of potassium ions, and membrane potential hyperpolarization. Confocal laser scanning microscopy and field-emission-gun scanning electron microscope assays revealed clear membrane damage due to juglone treatment. Fourier transform infrared analyses showed that L. monocytogenes responded to juglone by some conformational and compositional changes in the molecular makeup of the cell membrane. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that juglone either destroyed proteins or inhibited proteins synthesis in L. monocytogenes. Therefore, our findings established juglone as a natural antibacterial agent with potential to control foodborne L. monocytogenes infections.

Vilazodone-phospholipid mixed micelles for enhancing oral bioavailability and reducing pharmacokinetic variability between fed and fasted states

Despite the effectiveness and high tolerability of vilazodone (VLZ) as an antidepressant, its use is still limited due to its poor solubility and food dependent absorption. This study aims to load VLZ-phospholipid complex into self-assembled micelles forming VLZ-PL mixed micelles (VLZ-PL-MM), that can enhance VLZ solubility, improve its bioavailability and reduce the pharmacokinetic variability between the fed and fasting conditions. The effect of the surfactant type and concentration was assessed using four different non-ionic surfactants (Brij 58, Tween 80, Labrasol and Pluronic F127) in four different weight ratios between the drug-complex and surfactant (1:0.5, 1:1, 1:2 and 1:3 w/w). Two VLZ-PL-MM formulae prepared using Brij 58 and Labrasol in 1:3 w/w ratio were selected as optimised ones since they have the highest encapsulation efficiency (100.83 and 93.87%, respectively), a particle size below 250 nm (206.73 and 221.33 nm, respectively) and negative zeta potential values (-29.63, -17.20 mV, respectively). Lyophilisation of these formulations using 3% sucrose was successful with no statistical changes in particle size and zeta potential upon rehydration. Both formulations elicited faster and higher in-vitro drug release profiles compared to the pure drug and the marketed tablet. In addition, both selected formulae improved ex-vivo permeation across rabbit intestinal membrane compared to the pure drug and the marketed tablet, with marked superiority of the one prepared using Brij 58. The results of the in vivo study in male albino rabbits revealed similar AUC_0-24 values after the oral administration of the best achieved VLZ-PL-MM system under fed and fasting conditions (769.89 and 741.55 ng.h mL^-1, respectively). On the other hand, the marketed product showed significantly lower values of the AUC_0-24 relative to the VLZ-PL-MM system and there was a marked enhancement of absorption of drug from the marketed product in presence of food (244.24 and 174.96 ng.h mL^-1 under fed and fasting conditions, respectively. In addition, VLZ concentrations in the brain after 24 hours obtained from the selected VLZ-PL-MM were significantly higher than those obtained from marketed tablet under fed and fasting conditions. Thus, the phospholipid mixed micelle formulation enhances the oral bioavailability of the poorly soluble drug and reduces the pharmacokinetic variability between fasting and fed conditions.

Molecular biological mechanism of action in cancer therapies: Juglone and its derivatives, the future of development

Juglone (5 - hydroxy - 1, 4 - naphthalene diketone) is a kind of natural naphthoquinone, present in the roots, leaves, nut-hulls, bark and wood of walnut trees. Recent studies have found that Juglone has special significance in the treatment of cancer, which plays a significant role in the resistance of cancer cell proliferation, induction of cancer cell apoptosis, induction of autophagy, anti-angiogenesis and inhibition of cancer cell migration and invasion, etc. Additionally, its derivatives also play a tumor suppressive effect. In conclusion, Juglone and its derivatives have been identified as effective anticancer drugs. This paper reviews action mechanisms of Juglone and its derivatives in cancer treatment.

Increased antitumor efficacy of ginsenoside Rh2 via mixed micelles: in vivo and in vitro evaluation

The aim of this work is to apply Solutol^® HS15 and TPGS to prepare self-assembled micelles loading with ginsenoside Rh₂ to increase the solubility of ginsenoside Rh₂, hence, improving the antitumor efficacy. Ginsenoside Rh₂-mixed micelles (Rh₂-M) were prepared by thin film dispersion method. The optimal Rh₂-M was characterized by particle size, morphology, and drug encapsulation efficiency. The enhancement of in vivo anti-tumor efficacy of Rh₂-M was evaluated by nude mice bearing tumor model. The solubility of Rh₂ in self-assembled micelles was increased approximately 150-folds compared to free Rh₂. In vitro results demonstrated that the particle size of Rh₂-M is 74.72 ± 2.63 nm(PDI = 0.147 ± 0.15), and the morphology of Rh₂-M is spherical or spheroid, and the EE% and LE% are 95.27 ± 1.26% and 7.68 ± 1.34%, respectively. The results of in vitro cell uptake and in vivo imaging showed that Rh₂-M could not only increase the cell uptake of drugs, but also transport drug to tumor sites, prolonging the retention time. In vitro cytotoxicity and in vivo antitumor results showed that the anti-tumor effect of Rh₂ can be effectively improved by Rh₂-M. Therefore, Solutol^® HS15 and TPGS could be used to entrapping Rh₂ into micelles, enhancing solubility and antitumor efficacy.

Optimization and Characterization of Brimonidine Tartrate Nanoparticles-loaded In Situ Gel for the Treatment of Glaucoma

Purposes: The present study aimed to develop brimonidine tartrate loaded poly(lactic-co-glycolic acid) acid vitamin E-tocopheryl polyethylene glycol 1000 succinate (BRT-PLGA-TPGS) nanoparticles in thermosensitivein situ gel to improve mucoadhensive properties and drug holding capacity for the better management of glaucoma.Methods: Nanoparticles was optimized by means of Box-Behnken Design (BBD). The formulations were prepared using various concentration of PLGA (0.1-0.4% w/v) and TPGS (0.3-0.5% w/v). The analytical data of fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and transmission electron microscopy (TEM) depicted the drug excipients compatibility and confirmed the nanoparticles. Nanoparticles incorporated gel was evaluated for transcorneal permeability, gelation time, gelling temperature, and rheological studies. In addition, in vitro, transcorneal permeation drug release studies and intraocular pressure (IOP) for optimized gel was also performed. Biocompatibility of formulations was investigated in rabbit model.Results: The drug loaded nanoparticles exhibited 115.72 ± 4.18 nm, 0.190 ± 0.02, -11.80 ± 2.24 mV and 74.85 ± 6.54% of mean size, polydispersity index (PDI), zeta potential and entrapment efficiency (% EE), respectively. As compared to marketed eye drop, the sustained and continuous release BRT release from Poloxamer-based in situ gel was 85.31 ± 3.51% till 24 h. The transcorneal steady-state flux (136.32 μg cm^-2 h^-1) of optimized in situ gel was approximately 3.5 times higher than marketed formulation (38.60 μg cm^-2 h^-1) flux at 4 h. The optimized formulation produces 3 fold greater influences on percentage reduction of IOP (34.46 ± 4.21%) than the marketed formulation (12.24 ± 2.90%) till 8 h.Conclusion: The incorporation of optimized BRT-PLGA-TPGS nanoparticles into a thermosensitivein situ gel matrix to improve precorneal residence time without causing eye irritation and also serve the sustained release of BRT through cornea for effective management of glaucoma.

Potential Anti-Tumor Activity of Kefir-Induced Juglone and Resveratrol Fractions Against Ehrlich Ascites Carcinoma-Bearing BALB/C Mice

We investigated the potential influence of kefir-induced juglone and resveratrol fractions (JRK) against Ehrlich Ascites Carcinoma (EAC) bearing BALB/c male mice. Kefir yeast was grown in the cell culture supplemented with juglone and resveratrol (1:2). After 48 h incubation, JRK solution was applied (0.1 mL/day i.p.) to the EAC-bearing mice throughout five days. Molecular regulatory mechanisms of apoptotic and anti-apoptotic pathway components were evaluated in the plasma of mice and isolated EAC cells with ELISA, qRT-PCR, and immunocytchemical experiments. EAC-induced upregulation in Bcl-2 and downregulation in Caspase-3 were normalized with JRK in the plasma of mice. Additionally, JRK upregulated the expression levels of apoptotic Bax, p53, Caspase-3,8,9, and APAF-1 proteins together with BAX, CASPASE-8, and CASPASE-9 genes in isolated EAC cells. These changes were also associated with decreased expression levels of anti-apoptotic Bcl-2 and Bcl-xl proteins. Immunocytochemical studies also confirmed the activation of apoptotic pathways and repression of anti-apoptotic proteins in EAC cells with JRK treatment. JRK activates apoptotic pathway and inhibits anti-apoptotic genes and proteins in Ehrlich ascites carcinoma- bearing BALB/c mice that could be beneficial in cancer treatment.

Poloxamer-188 and d-α-Tocopheryl Polyethylene Glycol Succinate (TPGS-1000) Mixed Micelles Integrated Orodispersible Sublingual Films to Improve Oral Bioavailability of Ebastine; In Vitro and In Vivo Characterization

Orodispersible sublingual films (OSFs) composed of hydrophilic polymers were loaded with poloxamer-188 and d-α-tocopheryl polyethylene glycol succinate (TPGS-1000) mixed micelles to improve the oral bioavailability of a poorly soluble drug, ebastine (EBT). Mixed micelles formed by thin-film hydration method were incorporated into orodispersible sublingual film, consisting of HPMC and glycerol, using solvent casting technique. The mixed micelles and films were thoroughly evaluated for physicochemical characterization (size, polydispersity index, zeta potential, entrapment efficiency, thickness, weight, surface pH studies, disintegration time, swelling indices, mechanical properties, FTIR, PXRD, DSC, SEM, AFM, in vitro drug release, in vivo bioavailability, and toxicological studies). The results showed that the average particle size of mixed micelles was 73 nm. The mean zeta potential and PDI of the optimal mixed micelles formulation were -26 mV and 0.16, respectively. Furthermore, the maximum entrapment efficiency 82% was attained. The film's disintegration time was in the range of 28 to 102 s in aqueous media. The integrity of micelles was not affected upon incorporation in films. Importantly, the micelles-loaded films revealed rapid absorption, high permeability, and increased bioavailability of EBT as compared to the pure drug. The existence of ebastine loaded mixed micelles in the films enhanced the bioavailability about 2.18 folds as compared to pure drug. Further, the results evidently established in-vitro and in-vivo performance of bioavailability enhancement, biocompatibility, and good safety profile of micelles-loaded orodispersible EBT films. Finally, it was concluded that film loaded with poloxamer-188/TPGS-1000 mixed micelles could be an effective carrier system for enhancing the bioavailability of ebastine.

Enhanced oral bioavailability of magnolol via mixed micelles and nanosuspensions based on Soluplus®-Poloxamer 188

Magnolol, known to have extensive biological activities, is the major bioactive ingredient isolated from the root and stem bark of Magnolia officinalis. However, the clinical application of magnolol is limited by poor aqueous solubility and absorption. The aim of this study is to develop novel mixed micelles and nanosuspensions composed of two biocompatible copolymers, Soluplus® and Poloxamer 188, and to improve the solubility and oral bioavailability of magnolol. The magnolol-loaded mixed micelles (MMs) and magnolol nanosuspensions (MNs) were prepared to use film hydration and antisolvent methods, respectively. The optimal MMs and MNs formulations were prepared to use magnolol, Soluplus®, and Poloxamer 188 in ratios of 1:12:5 and 2:1:1, respectively. The average particle size of MMs was 111.8 ± 14.6, and MNs was 78.53 ± 5.4 nm. The entrapment and drug loading efficiency for MMs were 89.58 ± 2.54% and 5.46 ± 0.65%, correspondingly. The drug loading efficiency of MNs was 42.50 ± 1.57%. In the in vitro release study, MMs showed a slow drug release while that of MNs was fast. The results of the Caco-2 transcellular transport study indicated that both MMs and MNs increased the permeation of magnolol. MMs and MNs markedly promoted gastrointestinal drug absorption by 2.85 and 2.27-fold, respectively, as shown in the pharmacokinetics study. These results indicated that both MMs and MNs formulations prepared with Soluplus® and Poloxamer 188 are promising drug delivery systems for improving the oral absorption of insoluble drugs in the gastrointestinal tract.

Harmonious Biomaterials for Development of In situ Approaches for Locoregional Delivery of Anti-cancer Drugs: Current Trends

Locoregional drug delivery is a novel approach for the effective delivery of anti-cancer agents as it exposes the tumors to high concentration of drugs. In situ gelling systems have fetched paramount attention in the field of localized cancer chemotherapy due to their targeted delivery, ease of preparation, prolonged or sustained drug release and improved patient compliance. Numerous polymers have been investigated for their properties like swelling along with biodegradation, drug release and physicochemical properties for successful targeting of the drugs at the site of implantation. The polymers such as chitosan, Hyaluronic Acid (HA), poloxamer, Poly Glycolic Lactic Acid (PGLA) and Poly Lactic Acid (PLA) tend to form in situ hydrogels and have been exploited to develop localized delivery vehicles. These formulations are administered in the solution form and on exposure to physiological environment such as temperature, pH or ionic composition they undergo phase conversion into a hydrogel drug depot. The use of in situ gelling approach has provided prospects to increase overall survival and life quality of cancer patient by enhancing the bioavailability of drug to the site of tumor by minimizing the exposure to normal cells and alleviating systemic side effects. Because of its favorable safety profile and clinical benefits, United States Food and Drug Administration (U.S. FDA) has approved polymer based in situ systems for prolonged locoregional activity. This article discusses the rationale for developing in situ systems for targeted delivery of anti-cancer agents with special emphasis on types of polymers used to formulate the in situ system. In situ formulations for locoregional anti-cancer drug delivery that are marketed and are under clinical trials have also been discussed in detail in this article.

Natural Products to Fight Cancer: A Focus on Juglans regia

Even if cancer represents a burden for human society, an exhaustive cure has not been discovered yet. Low therapeutic index and resistance to pharmacotherapy are two of the major limits of antitumour treatments. Natural products represent an excellent library of bioactive molecules. Thus, tapping into the natural world may prove useful in identifying new therapeutic options with favourable pharmaco-toxicological profiles. Juglans regia, or common walnut, is a very resilient tree that has inhabited our planet for thousands of years. Many studies correlate walnut consumption to beneficial effects towards several chronic diseases, such as cancer, mainly due to the bioactive molecules stored in different parts of the plant. Among others, polyphenols, quinones, proteins, and essential fatty acids contribute to its pharmacologic activity. The present review aims to offer a comprehensive perspective about the antitumour potential of the most promising compounds stored in this plant, such as juglanin, juglone, and the ellagitannin-metabolites urolithins or deriving from walnut dietary intake. All molecules and a chronic intake of the fruit provide tangible anticancer effects. However, the scarcity of studies on humans does not allow results to be conclusive.

Improved oral bioavailability of magnolol by using a binary mixed micelle system

The aim of this study was to prepare two novel magnolol (MO)-loaded binary mixed micelles (MO-M) using biocompatible copolymers of Soluplus (SOL) and Solutol^® HS15 (HS15), SOL and d-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS), to improve magnolol's poor solubility and its oral bioavailability. The organic solvent evaporation method was used to obtain two MO-M by optimization; one was prepared by using SOL and HS15 (MO-H), and the other was prepared by using SOL and TPGS (MO-T). The entrapment efficiency (EE%) and drug loading (DL%) of MO-T were 94.61 ± 0.91% and 4.03 ± 0.19%, respectively, and the MO-H has higher EE% and DL% (98.37 ± 1.23%, 4.12 ± 0.16%). TEM results showed that the morphology of MO-M was homogeneous and was spherical in shape. The dilution stability of MO-M did not undergo significant changes. Permeability of MO-M across a Caco-2 cell monolayer was enhanced in Caco-2 cell transport models. The pharmacokinetics study showed that the relative oral bioavailability of MO-T and MO-H increased by 2.39- and 2.98-fold, respectively, compared to that of raw MO. This indicated that MO-H and MO-T could promote absorption of MO in the gastrointestinal tract. Collectively, the mixed micelles demonstrated greater efficacy as a drug delivery system. The development of these novel mixed micelles is valuable for resolving the poor solubility and bioavailability of drugs.

Preparation of ginsenoside compound-K mixed micelles with improved retention and antitumor efficacy

Introduction

Ginsenoside compound K (CK) has effects on cell-cycle regulation, tumor growth inhibition, and apoptosis induction. However, it has limited applications in clinical settings because of its low solubility and poor absorption.

Methods

To overcome these limitations, we aimed to develop a mixed micellar system composed of phosphatidylcholine (PC) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine polyethylene glycol 2000 (DSPE PEG 2000; DP). CK encapsulated in PC/DP mixed micelles had enhanced solubility, permeability, and retention effects.

Results

Compared to free CK, the CK PC/DP micellar system exhibited improved anticancer effects in vitro, including cell-cycle arrest, apoptosis, and anti-invasion in human lung carcinoma A549 cells. The significant proapoptotic effect was reflected by increased chromosomal condensation, annexin V/propidium iodide staining, and related protein expression. In vitro cellular uptake and optical mouse imaging in vivo suggested that the improved antitumor effect was caused primarily by enhanced uptake and tumor targeting. Furthermore, an in vivo antitumor efficacy study indicated that the CK mixed micelles significantly inhibited tumor growth, thereby decreasing tumor volume at the end of the experiment as compared with that in the control mice. Histological analysis confirmed the antitumor effect with low toxicity.

Conclusion

The PC/DP micellar system was an effective drug delivery system for CK in tumor therapy.

Synergistic apoptotic effects of apigenin TPGS liposomes and tyroservatide: implications for effective treatment of lung cancer

To develop an alternative treatment for lung cancer, a combination of two potent chemotherapeutic agents – liposomal apigenin and tyroservatide – was developed. The therapeutic potential of this combination was investigated using A549 cells. Apigenin and tocopherol derivative-containing D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) liposomes might improve the delivery of apigenin to tumor cells, both in vitro and in vivo. Importantly, compared to either agent alone, the combination of apigenin TPGS liposomes and tyroservatide exhibited superior cytotoxicity, induced stronger G2 arrest, and suppressed A549 cancer cell invasion at a lower dose. The proapoptotic synergistic effects were also observed in A549 cells using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, flow cytometry, and Western blot analysis. More importantly, in vivo results showed that the combination of apigenin TPGS liposomes and tyroservatide exhibited tumor-growth inhibitory effects in A549 cell-bearing mice. In conclusion, our study showed that this combination therapy could serve as a promising synergistic therapeutic approach to improve outcomes in patients with lung cancer.

Surface-tailored nanomixed micelles containing quercetin–salicylic acid physical complex for enhanced cellular and in vivo activities: a quality by design perspective

Aim: The development of surface-tailored quercetin (QCT)–salicylic acid (SA) physical complex for effective treatment of skin carcinoma. Materials & methods: QCT–SA nanomixed micelles were prepared by the self-assembly method employing the Quality by Design (QbD) approach and evaluated for various in vitro, ex vivo and in vivo parameters. Results: The optimized formulation showed enhanced percent permeation (Q24), in other words, 78.12 ± 0.47, improved in vitro cellular uptake and annexin-V–apoptosis assay exhibited 60.86% cell death. The 7,12-dimethylbenz(a)anthracene and histopathology protocol revealed the improved antineoplastic action of QCT. The dermatokinetic profile showed the maximum drug concentration (6 h), in other words, 416.02 ± 26 μg/cm2 in epidermis and 103.65 ± 12 μg/cm2 in dermis. Conclusion: The overall performance ratified the safety and efficacy of optimized nanomixed micelless of QCT with SA in a synergistic manner.