Tocopheryl Polyethylene Glycol Succinate Research Articles

Induction of Mitochondrial Cell Death and Reversal of Anticancer Drug Resistance via Nanocarriers Composed of a Triphenylphosphonium Derivative of Tocopheryl Polyethylene Glycol Succinate.

We have devised a nanocarrier using "tocopheryl polyethylene glycol succinate (TPGS) conjugated to triphenylphosphonium cation" (TPP-TPGS) for improving the efficacy of doxorubicin hydrochloride (DOX). Triphenylphosphonium cation (TPP) has affinity for an elevated transmembrane potential gradient (mitochondrial), which is usually high in cancer cells. Consequently, when tested in molecular docking and cytotoxicity assays, TPP-TPGS, owing to its structural similarity to mitochondrially directed anticancer compounds of the "tocopheryl succinate" family, interferes specifically in mitochondrial CII enzyme activity, increases intracellular oxidative stress, and induces apoptosis in breast cancer cells. DOX loaded nanocarrier (DTPP-TPGS) constructed using TPP-TPGS was positively charged, spherical in shape, sized below 100 nm, and had its drug content distributed evenly. DTPP-TPGS offers greater intracellular drug delivery due to its rapid endocytosis and subsequent endosomal escape. DTPP-TPGS also efficiently inhibits efflux transporter P glycoprotein (PgP), which, along with greater cell uptake and inherent cytotoxic activity of the construction material (TPP-TPGS), cumulatively results in 3-fold increment in anticancer activity of DOX in resistant breast cancer cells as well as greater induction of necroapoptosis and arrest in all phases of the cell cycle. DTPP-TPGS after intravenous administration in Balb/C mice with breast cancer accumulates preferentially in tumor tissue, which produces significantly greater antitumor activity when compared to DOX solution. Toxicity evaluation was also performed to confirm the safety of this formulation. Overall TPP-TPGS is a promising candidate for delivery of DOX.

Indometacin-loaded micelles based on star-shaped PLLA-TPGS copolymers: effect of arm numbers on drug delivery

Star-shaped copolymers based on star-shaped poly (L-lactide) (s-PLLA) and tocopheryl polyethylene glycol 1000 succinate (TPGS) (s-PLLA-TPGS) were synthesized with structural variation on arm numbers in order to investigate the relationship between the arm numbers of s-PLLA-TPGS copolymers and their micelle properties. The structure and Mw of s-PLLA-TPGS were characterized with 1H NMR, GPC, DSC, and XRD. The indometacin(IMC)-loaded s-PLLA-TPGS micelles were obtained by dialysis method. The effects of arm numbers of s-PLLA-TPGS copolymers on surface morphology, particle size, zeta potential, drug loading content (LC), drug encapsulation efficiency (EE), and in vitro drug release behavior of prepared micelles were studied. The results indicated that the average diameters, LC, and EE of IMC-loaded s-PLLA-TPGS micelles gradually increased in the order of 4-arm, 5-arm, and 6-arm s-PLLA-TPGS copolymers. The in vitro release studies showed that the IMC accumulative release can be decreased by increasing the arm numbers of the s-PLLA-TPGS copolymers, and the release profiles of IMC from the s-PLLA-TPGS copolymers followed the Baker-Lonsdale model equation. The results suggest that the arm number regulation of s-PLLA-TPGS copolymers can provide a new strategy for designing drug carriers of high efficiency.

Vitamin E TPGS based palatable, oxidatively and physically stable emulsion of microalgae DHA oil for infants, children and food fortification

Clinically, Docosahexaenoic acid (DHA) has been implicated for the prevention of cognitive disorders and is considered as a vital component for normal brain development, especially in infants and children’s. However, clinical uses of microalgae DHA oil are limited due to its compromised physical- and oxidative- stability along with poor organoleptic properties. Thus, in this present study, a stable and palatable pharmaceutical emulsion formulation having an extended shelf life was investigated using Vitamin E TPGS (Tocopheryl polyethylene glycol succinate) as biosurfactant. Optimized emulsion was found to have better oxidative and physical stability with lower peroxide formation and no creaming under all storage conditions. Rancimat analysis exhibited increased induction point in comparison to plain DHA oil and commercial formulation. Further, in rheological analysis better thixotropic behavior with 100% recovery of optimized emulsion was observed. Prepared emulsion was also found palatable and suitable for fortifications of juice, milk and other beverages during sensory analysis. Ex vivo intestinal permeability exhibited 2 folds increase in DHA absorption with permeability coefficient (3.83 × 10−6 cm s−1) in comparison to commercial (1.75 × 10−6 cm s−1). Improved in vivo pharmacodynamic activity and 1.4 folds increase in bioavailability in comparison to DHA oil during the pharmacokinetic study was observed, demonstrating the better bioavailability of Vitamin E TPGS based emulsion formulation. Thus, this study provided an insight for a pharmaceutically effective composition of DHA emulsion having extended storage shelf life, oxidative and physical stability and food fortification ability.

Gellan Gum Based Sol-to-Gel Transforming System of Natamycin Transfersomes Improves Topical Ocular Delivery.

Short precorneal residence time and poor transocular membrane permeability are the major challenges associated with topical ocular drug delivery. In the present research, the efficiency of the electrolyte-triggered sol-to-gel-forming system of natamycin (NT) transfersomes was investigated for enhanced and prolonged ophthalmic delivery. Transfersomes were optimized by varying the molar ratios of phospholipid, sorbitan monostearate (Span) and tocopheryl polyethylene glycol succinate (TPGS). NT transfersome formulations (FNs) prepared with a 1:1 molar ratio of phospholipid-to-Span and low levels of TPGS showed optimal morphometric properties, and were thus selected to fabricate the in situ gelling system. Gellan gum-based (0.3% w/v) FN-loaded formulations (FNGs) immediately formed an in situ gel in the simulated tear fluid, with considerable viscoelastic characteristics. In vitro cytotoxicity in corneal epithelial cells and corneal histology studies demonstrated the ocular safety and cytocompatibility of these optimized formulations. Transcorneal permeability of NT from these formulations was significantly higher than in the control suspension. Moreover, the ocular disposition studies of NT, from the FNs and FNGs, in New Zealand male albino rabbits demonstrated the superiority of the electrolyte-sensitive FNGs in terms of NT delivery to the ocular tissues.

Curcumin loaded TPGS micelles for nose to brain drug delivery: in vitro and in vivo studies

ABSTRACTThe effective treatment of brain cancer is hindered by the poor transport across the blood-brain barrier (BBB) and the low penetration across the blood-tumour barrier (BTB). The main objective of this work was to the development of stable micelles of curcumin which may enhance the brain targeting of CRM via intranasal administration. Curcumin-loaded D-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) micelles were prepared by thin film hydration method and characterized for their particle sizes and zeta potential. The morphological study was done by transmission electron microscopy. The particle sizes of the curcumin-loaded targeted micelles were 146.8 nm. About 98.19 ± 1.2% of drug encapsulation efficiency was achieved with micelles. The in vivo study results indicated that curcumin loaded TPGS micelles could be a promising carrier for brain targeting in comparison to the non-targeted micelles.

Formulation and In- Vitro Evaluation of Spherical Crystal Agglomerates of Ebastine by Quasi Emulsion Solvent Diffusion Method

Ebastine (EBS) is a poorly water-soluble antihistaminic drug; it belongs to the class II group according to the biopharmaceutical classification system (BCS). The aim of the present work was to enhance the solubility, dissolution rate and micromeritic properties of the drug, by formulating it as spherical crystal agglomerates by Quasi Emulsion Solvent Diffusion (QESD) method.
 Spherical crystal agglomerates (SCAs) were prepared in presence of three solvents dichloromethane (DCM), water and chloroform as a good solvent, poor solvent and bridging solvent respectively. Agglomeration of EBS involved the use of some hydrophilic polymers like polyethylene glycol 4000 (PEG 4000), polyvinyl pyrrolidine K30 (PVP K30), D-?-tocopheryl polyethylene glycol 1000 succinate (TPGS) and ?. cyclodextrin. The pure drug (EBS) and its agglomerates with and without polymers were characterized for their drug content, percentage yield, solubility, in vitro drug release study and micromeritic property as well as by optical microscope, Scanning Electron Microscopy (SEM), FTIR spectroscopic studies, Differential Scanning Calorimetry (DSC) and X-ray Diffraction (XRD). The results of this work showed that there was a marketed enhancement in the solubility with improvement in dissolution rate, physiochemical properties, decrease in crystallinity and alteration in the crystal habit of the drug especially in presence of polymers. The best results were obtained with formula prepared by the combination of PEG 4000 and B. cyclodextrin in the agglomeration process of (EBS).

Topical anesthesia therapy using lidocaine-loaded nanostructured lipid carriers: tocopheryl polyethylene glycol 1000 succinate-modified transdermal delivery system.

PurposeTransdermal drug delivery of local anesthetics using lipid nanoparticles could enhance lipophilic drugs permeation through the stratum corneum, improve drug diffusion to deeper skin, and exert good therapeutic effects. The purpose of this study was to engineer a Tocopheryl Polyethylene Glycol 1000 Succinate (TPGS)-modified cationic nanostructured lipid carriers (NLC) for the delivery of lidocaine (LID; TPGS/LID-NLC).Materials and methodsTPGS/LID-NLC was prepared by solvent diffusion method. The particle size, polydispersity index, zeta potential, drug entrapment efficiency, drug loading, stability, drug release, and cytotoxicity were tested to evaluate the basic characters of NLC. In vitro skin permeation and in vivo anesthesia effect in an animal model were further investigated to determine the therapeutic efficiency of the system.ResultsTPGS/LID-NLC had a particle size of 167.6±4.3 nm, a zeta potential of +21.2±2.3 mV, an entrapment efficiency of 85.9%±3.1%, and a drug loading of 11.5%±0.9%. A sustained release pattern was achieved by TPGS/LID-NLC, with 81.2% of LID released at 72 hours. In vitro permeation study showed that the steady-state fluxes (Jss), permeability coefficient (Kp), and cumulative drug permeation Qn at 72 hours (Q72) of TPGS/LID-NLC were 15.6±1.8 µg/cm2/hour, 10.3±0.9 cm/hour (×10−3), and 547.5±23.6 µg/cm2, respectively, which were significantly higher than the nonmodified NLC and free drug groups. In vivo anesthesia effect of TPGS/LID-NLC was the most remarkable and long acting among the formulations tested, which could be concluded by the most considerable maximum possible effect from 10 to 120 minutes during the whole research.ConclusionThe most prominent in vitro permeation efficiency and in vivo anesthetic effect of TPGS/LID-NLC could be the evidence that TPGS-modified NLC could function as a promising drug delivery system for prolonged and efficient local anesthetic therapy.

A thorough analysis of the effect of surfactant/s on the solubility and pharmacokinetics of (S)-zaltoprofen

Until now, there are no publications about the preformulation studies on (S)-zaltoprofen ((S)-ZPF). Hence, we first investigated the solubility of (S)-ZPF, screened solubilizers and performed the pharmacokinetic study of (S)-ZPF in the presence of the solubilizers. The measurement of the solubility of (S)-ZPF in 26 different solvents was carried out, including d-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS), 2-hydroxypropyl-β-cyclodextrin (HPCD), and mixtures of individual solvent. The plasma concentration of (S)-ZPF and the amount of (S)-ZPF retained in stomach were determined after oral (35.0 mg/kg) and intravenous (5.0 mg/kg) administration. The solubility of (S)-ZPF showed an increase of 484-fold in TPGS compared to its aqueous solubility. There was a significant increase of AUC0-24 h for pure (S)-ZPF in the TPGS group (813.59 ± 64.17 µg⋅h/ml) in comparison with AUC0-24 h in the HPCD group (595.57 ± 71.76 µg⋅h/ml) and water group (465.57 ± 90.89 µg⋅h/ml). In addition, the Tmax of (S)-ZPF in the TPGS group was 2 h, much faster than that in the HPCD or water groups (5.50 or 5.67 h, respectively). This suggested that TPGS played a significant role in the increase of solubility and bioavailability of (S)-ZPF.

TPGS-functionalized and ortho ester-crosslinked dextran nanogels for enhanced cytotoxicity on multidrug resistant tumor cells

Herein pH-sensitive nanogels (NG1) and P-glycoprotein-repressive nanogels (NG2) were prepared by copolymerization between an ortho ester crosslinker (OEAM) and tocopheryl polyethylene glycol succinate (TPGS)-free or conjugated dextran. Nanogels with or without TPGS possessed a uniform diameter (∼180 nm) and excellent stability in various physiological environments. Doxorubicin (DOX) was successfully loaded into NG1 and NG2 to give NG1/DOX and NG2/DOX, both of them showed appropriate drug release profiles under mildly acidic conditions (pH 5.0). NG2/DOX possessed higher drug enrichment and lethality than NG1/DOX did on MCF-7/ADR cells. Analysis of corresponding index of efflux activity showed that NG2 could induce depolarization of mitochondrial membrane and interfere with ATP metabolism. NG2/DOX also displayed increased penetration and growth inhibition on MCF-7/ADR multicellular spheroids. These results demonstrated that pH-sensitive TPGS-functionalized nanogels (NG2) as drug carriers had great potential to suppress drug efflux in MCF-7/ADR cells and even overcome MDR on cancer cells.

Solid dispersion of dutasteride using the solvent evaporation method: Approaches to improve dissolution rate and oral bioavailability in rats

The aim of this study was to develop a dutasteride (DUT) solid dispersion (SD) using hydrophilic substances to enhance its dissolution (%) and oral bioavailability in rats. DUT-SD formulations were prepared with various co-polymers using a solvent evaporation method. The physical properties of DUT-SD formulations were confirmed using field emission scanning electron microscopy (FE-SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy. The toxicity and oral bioavailability of DUT-SD formulations were evaluated. Tocopheryl polyethylene glycol-1000-succinate (TPGS) was chosen as the solubilizer; and methylene chloride, and Aerosil® 200 or microcrystalline cellulose (MCC) were chosen as the solvent and carrier, respectively, based on a solubility test and pre-dissolution study. The dissolution levels of DUT-SD formulations were 86.3 ± 2.3% (F15) and 95.1 ± 1.9% (F16) after 1 h, which were higher than those of the commercial product, i.e., Avodart® (75.8 ± 1.5%) in 0.1 N HCl containing 1% (w/v) sodium lauryl sulfate (SLS). The F16 formulation was found to be stable, after assessing its dissolution (%) and drug content (%) for 6 months. The DUT-SD formulations resulted in relative bioavailability (BA) values of 126.4% (F15) and 132.1% (F16), which were enhanced compared to that of Avodart®. Dissolution (%) and relative BA values were both increased by hydrogen interaction between TPGS and DUT. This study might contribute to a new formulation (powder) whose oral bioavailability is greater than that of Avodart® (soft capsule), which could facilitate to the use of the SD system during the production process.

Quercetin‑loaded mixed micelles exhibit enhanced cytotoxic efficacy in non‑small cell lung cancer in vitro

In the present study, quercetin (QUR)-loaded mixed micelles (QUR-M) were prepared with the aim of improving the physicochemical and anticancer efficacy of QUR in lung cancer cells. The mixed micelles comprised tocopheryl polyethylene glycol 1000 succinate (TPGS) and a 1,2-distearoyl-sn-glycero-3-phosphatidylethanolamine derivative of polyethylene glycol. The nanosized QUR-M exhibited a pH-responsive and controlled release of QUR that is likely to be beneficial in cancer treatment. The results of an MTT assay clearly demonstrated that the anticancer effect of QUR-M in A549 cancer cells was stronger compared with that of free QUR at 24 and 48 h time points. The half-maximal inhibitory concentrations of QUR and QUR-M were observed to be 12.45 and 6.42 µg/ml, respectively. When stained with Hoechst 33342 and observed using a confocal laser scanning microscope, A549 cells treated with QUR-M exhibited severe chromatin condensation and apoptotic body formation of the nuclei. Overall, high intracellular uptake, sustained drug release and the presence of TPGS in the mixed micelles may result in an increased inhibitory effect against cell proliferation and improved therapeutic efficacy in lung cancers.

The antitumor efficacy of docetaxel is enhanced by encapsulation in novel amphiphilic polymer cholesterol-coupled tocopheryl polyethylene glycol 1000 succinate micelles.

Tocopheryl polyethylene glycol 1000 succinate (TPGS) is considered a promising surfactant, but its high critical micelle concentration (CMC) limits its application. Cholesterol is hydrophobic, can act as a tumor-targeting ligand, and has strong binding ability with taxoids. Based on this information, we coupled cholesterol with TPGS to synthesize cholesterol-coupled TPGS (TPGS-CHMC), which had a lower CMC than pure TPGS. The TPGS-CHMC was used to prepare micelles loading with docetaxel (DTX) by a self-assembly method. DTX-loaded TPGS-CHMC micelles were globule-shaped, 13.3±2.0nm in size, and had a zeta potential of -4.66±0.41mv. In vitro release studies demonstrated the delayed release property of the micelles, which also had a relatively high encapsulation efficiency and drug loading content of 99.2 and 3.20%, respectively. Furthermore, the micelles were stable in vitro at a dilution of 100-fold. In vivo antitumor studies showed that the DTX-loaded TPGS-CHMC micelles significantly enhanced the antitumor activity of DTX in S180 tumor-bearing mice. Interestingly, the blank TPGS-CHMC micelles also showed antitumor activity. Our results demonstrate that TPGS-CHMC is a promising system for DTX delivery that may be suitable for other hydrophobic antitumor drugs.

Dual roles of TPGS based microemulsion for tacrolimus: Enhancing the percutaneous delivery and anti-psoriatic efficacy

In this study, we demonstrate for the first time the dual roles of Tocopheryl Polyethylene Glycol 1000 Succinate (TPGS) based microemulsion (ME) for tacrolimus (TAC) to enhance TAC percutaneous delivery and anti-psoriatic efficacy. The ME formulation was developed and optimized based on pseudo-ternary phase diagrams combined with in vitro permeation. The result of Fourier transform infrared spectroscopy (FTIR) demonstrated that TAC was completely solubilized in the TPGS-ME. In vitro permeation studies showed that TPGS-ME enhanced TAC permeation through and into the skin, and the enhanced deposition of TAC in the normal or psoriatic skin was further confirmed in vivo. The cellular uptake performed with HaCaT cells presented more pronounced uptake of TPGS-ME. Topical TAC-TPGS-ME treated imiquimod-induced psoriasis in mice more efficaciously than the commercial formulation of TAC (Protopic®), which is consistent with the enhanced TAC levels by TAC-TPGS-ME in the psoriatic skin. Haematoxylin and Eosin (HE) staining revealed that TAC-TPGS-ME significantly diminished the severity of the psoriasis-like skin inflammation. Moreover, TPGS-ME vehicle exhibited a moderate anti-inflammatory activity, which indicated that TPGS acted as a potential adjuvant in the TAC anti-psoriasis process, and the synergism was identified in anti-proliferation against HaCaT cells. The colloidal nano-carrier combined ME with TPGS is a potential approach for percutaneous delivery of TAC, which exploited both virtues of ME and TPGS to obtain the synergetic effects of enhanced permeability and anti-psoriatic efficacy.

Paclitaxel-loaded star-shaped copolymer nanoparticles for enhanced malignant melanoma chemotherapy against multidrug resistance.

Malignant melanoma (MM) is the most dangerous type of skin cancer with annually increasing incidence and death rates. However, chemotherapy for MM is restricted by low topical drug concentration and multidrug resistance. In order to surmount the limitation and to enhance the therapeutic effect on MM, a new nanoformulation of paclitaxel (PTX)-loaded cholic acid (CA)-functionalized star-shaped poly(lactide-co-glycolide) (PLGA)-D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles (NPs) (shortly PTX-loaded CA-PLGA-TPGS NPs) was fabricated by a modified method of nanoprecipitation. The particle size, zeta potential, morphology, drug release profile, drug encapsulation efficiency, and loading content of PTX-loaded NPs were detected. As shown by confocal laser scanning, NPs loaded with coumarin-6 were internalized by human melanoma cell line A875. The cellular uptake efficiency of CA-PLGA-TPGS NPs was higher than those of PLGA NPs and PLGA-TPGS NPs. The antitumor effects of PTX-loaded NPs were evaluated by the MTT assay in vitro and by a xenograft tumor model in vivo, demonstrating that star-shaped PTX-loaded CA-PLGA-TPGS NPs were significantly superior to commercial PTX formulation Taxol®. Such drug delivery nanocarriers are potentially applicable to the improvement of clinical MM therapy.

Formulation, optimization, and in vitro-in vivo evaluation of olmesartan medoxomil nanocrystals.

The aim of the present study is to increase the saturation solubility and oral bioavailability of olmesartan medoxomil (OLM) using nano-sized crystals produced using a combination of antisolvent precipitation and high-shear homogenization. A response surface design comprising 46 runs was used to optimize the OLM nanocrystal formulation. The optimized formulation was produced using a combination of D-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) (0.7% w/v), Pluronic F-68® (0.5% w/v), and drug concentration (0.2% w/v) and subjected to 10 and 15 homogenization cycles at 1000 and 1700bar, respectively. The particle size, polydispersity index (PDI), and zeta potential of optimized formulation were found to be 140±10.34nm, 0.07±0.016, and -21.43±2.33mV, respectively. The optimized formulation exhibited irregular morphology as evaluated by scanning electron microscopy and was crystalline as determined by thermal analysis and powder X-ray diffraction studies. OLM nanocrystals showed a marked increase in the saturation solubility as well as rapid dissolution rate in comparison with the pure drug. No significant change in the particle size, PDI, and zeta potential was observed when optimized formulation was stored at room and refrigeration conditions for 3months. Lastly, in vivo pharmacokinetic studies in Sprague-Dawley rats substantiate the ability of OLM nanocrystal formulation to significantly improve (∼4.6-fold) the oral bioavailability of OLM in comparison with the free drug. This study has established a potential and commercial viable OLM formulation with enhanced saturation solubility and in vivo oral bioavailability.

Improved oral bioavailability and therapeutic efficacy of dabigatran etexilate via Soluplus-TPGS binary mixed micelles system

The clinical use of dabigatran etexilate (DABE) is limited by its poor absorption and relatively low bioavailability. Our study aimed to explore the potential of a mixed micelle system composed of Soluplus® and D-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) to improve the oral absorption and bioavailability of DBAE. DBAE was first encapsulated into Soluplus/TPGS mixed micelles by a simple thin film hydration method. The DBAE loaded micelles displayed an average size distribution of around 83.13 nm. The cellular uptake of DBAE loaded micelles in Caco-2 cell monolayer was significantly enhanced by 2–2.6 fold over time as compared with DBAE suspension. Both lipid raft/caveolae and macropinocytosis-mediated the cell uptake of DBAE loaded micelles through P-glycoprotein (P-gp)-independent pathway. Compared with the DBAE suspension, the intestinal absorption of DBAE from DBAE mixed micelles in rats was significantly improved by 8 and 5-fold in ileum at 2 h and 4 h, respectively. Moreover, DBAE mixed micelles were absorbed into systemic circulation via both portal vein and lymphatic pathway. The oral bioavailability of DBAE mixed micelles in rats was 3.37 fold higher than that of DBAE suspension. DBAE mixed micelles exhibited a comparable anti-thrombolytic activity with a thrombosis inhibition rate of 63.18% compared with DBAE suspension in vivo. Thus, our study provides a promising drug delivery system to enhance the oral bioavailability and therapeutic efficacy of DBAE.

Solid lipid nanoparticles with TPGS and Brij 78: A co-delivery vehicle of curcumin and piperine for reversing P-glycoprotein-mediated multidrug resistance in vitro

Multidrug resistance (MDR) is a main clinical hurdle for chemotherapy of cancer, and overexpression of P-glycoprotein (P-gp) is a key factor. In the present study, a new co-delivery system for reversing MDR was designed and developed. The system was composed of curcumin (Cur) and piperine (Pip) encapsulated in solid lipid nanoparticles (SLNs) with tocopheryl polyethylene glycol succinate (TPGS) and Brij 78 [(Cur+Pip)-SLNs]. TPGS and Brij 78 could sensitize MDR tumors by inhibiting the P-gp drug efflux system. The combination of Cur and Pip, when administered in SLNs formulations, resulted in a significant enhancement in cytotoxicity and allowed efficient intracellular delivery of the drugs in drug-resistant A2780/Taxol cells. This dual inhibitory strategy may have significant potential in the clinical management of MDR in cancer.

Preparation and antitumor evaluation of self-assembling oleanolic acid-loaded Pluronic P105/d-α-tocopheryl polyethylene glycol succinate mixed micelles for non-small-cell lung cancer treatment.

Oleanolic acid (OA) is a triterpenoid found in various fruits and vegetables and used in traditional Chinese medicine. OA plays a crucial role in the treatment of several cancers, but poor water solubility, low permeability, and significant efflux have limited its widespread clinical use. Vitamin E-d-α-tocopheryl polyethylene glycol succinate (vitamin E-TPGS) and Pluronic P105 were used to improve the solubility and permeability and to decrease the efflux of OA. OA-loaded mixed micelles were prepared by ethanol thin-film hydration. The physicochemical properties of the micelles, including zeta potential, morphology, particle size, solubility, drug loading, and drug entrapment efficiency were characterized. OA release from micelles was slower than that from the free drug system. OA uptake by A549 non-small-cell lung cancer (NSCLC) cells was enhanced by the micelles. A tumor model was established by injecting A549 cells into nude mice. In vivo imaging showed that OA-micelles could accumulate in the tumors of nude mice. Additionally, smaller tumor size and increased expression of pro-apoptotic proteins were observed in OA-micelle-treated mice, indicating that OA-micelles are more effective than free OA in treating cancer. In vitro experiments were performed using two NSCLC cell lines (A549 and PC-9). Cytotoxicity evaluations showed that the half-maximal inhibitory concentrations of free OA and OA-micelles were 36.8±4.8 and 20.9±3.7 μM, respectively, in A549 cells and 82.7±7.8 and 56.7±4.7 μM, respectively, in PC-9 cells. Apoptosis assays revealed that the apoptotic rate of OA-micelle-treated A549 and PC-9 cells was higher than that of cells treated with the same concentration of free OA. Wound healing and transwell assays showed that migration and invasion were significantly suppressed in OA-micelle-treated cells. Immunofluorescence and Western blot analyses confirmed that the epithelial–mesenchymal transition was reversed in OA-micelle-treated cells. Mixed micelles are a promising nano-drug delivery system for lung cancer treatment.

In-situ single pass intestinal permeability and pharmacokinetic study of developed Lumefantrine loaded solid lipid nanoparticles

The present investigation aims to develop lumefantrine loaded binary solid lipid nanoparticles (LF-SLNs) to improve its poor and variable oral bioavailability. The oral bioavailability of LF is poor and variable due to its limited aqueous solubility and P-gp mediated efflux occurring in small intestine. LF-SLNs were prepared using binary lipid mixture of stearic acid and caprylic acid stabilized with TPGS (D-alpha tocopheryl polyethylene glycol 1000 succinate) and Poloxamer 188. Developed LF-SLNs were characterized for particle size distribution, zeta potential, entrapment efficiency, solid state properties and biopharmaceutical properties including in situ intestinal permeability and oral bioavailability. The particle size distribution, zeta potential and entrapment efficiency of optimized batch (LF-SLN7) was found to be 357.7±43.27nm, 25.29±1.15mV and 97.35±0.30%, respectively. DSC thermographs showed loss of crystalline nature of lumefantrine in LF-SLNs. In situ single pass intestinal permeability study (SPIP) study indicated significant enhancement in the effective intestinal permeability of LF from LF-SLN7 as compared to that of control. Pharmacokinetic study also showed significant increase in Cmax and area under curve (AUC0-∞) from LF-SLN7 (3860±521ng/mL and 43181±2557h×ng/mL, respectively) as compared to that of LF-control suspension (1425±563ng/mL and 19586±1537h×ng/mL, respectively). Thus, developed LF-SLNs can be promising to overcome P-gp efflux pump and enhance the oral bioavailability of lumefantrine.

Oleanolic acid loaded poly lactic co- glycolic acid- vitamin E TPGS nanoparticles for the treatment of Leishmania donovani infected visceral leishmaniasis

Oleanolic acid (OA) has low aqueous solubility and low permeability, which results poor bioavailability. To surmount the inadequacy, our aim was to fabricate oleanolic acid loaded poly lactic co- glycolic acid (PLGA)- d-α- tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles, which could be efficacious for the treatment of Leishmania donovani mediated visceral leishmaniasis (VL). OA loaded PLGA- TPGS nanoparticles were prepared by emulsion solvent evaporation technique. Cellular uptake was investigated. In vitro cumulative drug release study was carried out. In vitro susceptibility was confirmed against the amastigotes of Leishmania donovani AG83 wild and drug resistant strains. In vivo antileishmanial activity was evaluated against wild type amastigotes of L. donovani. OA loaded nanoparticles were successfully formulated. The highest drug loading was found to be 11.08%±0.35%. 85.66%±0.56% was the highest in vitro OA release for 30days among the formulations. In vivo study revealed that, 98.82±1.92% amastigote burden in spleen of BALB/c mice were suppressed by the polymeric nanoformulation of OA. Experimental OA nanoparticle formulation proved itself as an attractive carrier for OA which was significantly efficacious against both in vitro and in vivo amastigote form of Leishmania donovani than pure OA for chemotherapeutic intervention of visceral leishmaniasis.