Targeting prostate cancer with docetaxel-loaded peptide 563-conjugated PEtOx-co-PEI30%-b-PCL polymeric micelle nanocarriers.

Prostate cancer is a global disease that negatively affects the quality of life. Although various strategies against prostate cancer have been developed, only a few achieved tumor-specific targeting. Therefore, a special emphasis has been placed on the treatment of cancer using nano-carrier-encapsulated chemotherapeutic agents conjugated with tumor-homing peptides. The targeting strategy coupling the drugs with nanotechnology helps to overcome the most common barriers, such as high toxicity and side effects. Prostate-specific membrane antigen has emerged as a promising target molecule for prostate cancer and shown to be targeted with high affinity by GRFLTGGTGRLLRIS peptide known as peptide 563 (P563). Here, we aimed to assess the in vitro and in vivo targeting efficiency, safety, and efficacy of P563-conjugated, docetaxel (DTX)-loaded polymeric micelle nanoparticles (P563-PEtOx-co-PEI30%-b-PCL-DTX) against prostate cancer. To this end, we analyzed the cytotoxic activity of P563-PEtOx-co-PEI30%-b-PCL and P563-PEtOx-co-PEI30%-b-PCL-DTX by a cell proliferation assay using PNT1A and 22Rv1 cells. We have also determined the targeting selectivity of P563-PEtOx-co-PEI30%-b-PCL-FITC by flow cytometry and assessed the induction of cell death by western blot and TUNEL assays for P563-PEtOx-co-PEI30%-b-PCL-DTX in 22Rv1 cells. To investigate the in vivo efficacy, we administered DTX in the free form or in polymeric micelle nanoparticles to athymic CD-1 nu/nu mice 22Rv1 xenograft models and performed histopathological analyses. Our study showed that targeting prostate cancer with P563-conjugated PEtOx-co-PEI30%-b-PCL polymeric micelles could exert a potent anti-cancer activity with low side effects.

The Nanosuspension Formulations of Daidzein: Preparation and In Vitro Characterization

Objectives: Daidzein (DZ), a water-insoluble isoflavone, has many beneficial effects (anti-inflammatory, antioxidant, and anticancer effects, etc.) on human health. DZ has a very low oral bioavailability related to its physicochemical properties (low solubility, intense metabolism of DZ in the intestine and liver). This study aimed to prepare and in vitro characterize the nanosuspension formulations of DZ to improve the poor solubility and efficacy of DZ. Materials and Methods: DZ nanosuspension formulations were prepared with media milling technique using zirconium oxide beads as milling media. Pluronic F127 and polyvinylpyrrolidone (PVP) K30 (formulation A; F-A) and sodium dodecyl sulfate (SDS) (SDS + pluronic F127 + PVP K30; formulation B; F-B) were used as stabilizers. The nanosuspension formulations were evaluated for morphological properties, particle sizes, zeta potential, DZ content, saturation solubility, dissolution, and their cytotoxic effects on RG2 glioblastoma tumor cells. Results: F-A and F-B formulations were nanosized (in the range of about 181-235 nm) and had negative zeta potential values before and after lyophilization. The DZ content of F-A and F-B formulations were found to be 93.68±0.78% and 89.75±0.49%, respectively. Fourier transform infrared spectroscopy analysis showed that there was no significant interaction between DZ and the excipients. Differential scanning calorimetry and X-ray diffraction analyses confirmed no change in the crystal structure of DZ in F-A and F-B formulations. Conclusion: In this study, the nanosuspension formulations were successfully prepared and characterized in vitro. Nanosuspension formulations increased the saturation solubility, dissolution rate, and cytotoxic effect of DZ.

In Vitro Caco-2 Cell Permeability Studies of Ziprasidone Hydrochloride Monohydrate Nanocrystals

Objectives: The current study focused on the evaluation of the cytotoxic effect and permeability of ziprasidone hydrochloride monohydrate (ZHM) nanocrystals on Caco-2 cells. Materials and Methods: ZHM nanocrystals were prepared by the microfluidization method in the presence of polyvinylpyrrolidone as a stabilizer. Particle size (PS), particle size distribution (PDI), and zeta potential (ZP) values were measured in characterization studies. In vitro cytotoxic effects of ZHM nanocrystals were investigated using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Caco-2 transport studies were conducted with formulations of ZHM coarse powder and nanocrystals. Results: Nanocrystals were obtained with 400-600 nm PS, 0.1-0.4 PDI, and >20 mV ZP values. The cell viability remained 100% for all sample groups. The permeability value of ZHM nanocrystals through Caco-2 cells increased 2.3-fold in comparison with ZHM coarse powder. Cumulative drug transport also increased at the end of the sampling period. Conclusion: Nanocrystal technology helps to increase the permeability of drug particles by increasing the saturation solubility.

Formulation and In Vitro Evaluation of Telmisartan Nanoparticles Prepared by Emulsion-Solvent Evaporation Technique.

OBJECTIVES: Telmisartan (TLM) is an antihypertensive drug that has been shown to have antiproliferative effects on cancer cells. It has low solubility and suboptimal oral bioavailability. To investigate the potential anticancer effect of TLM on breast cancer cells, poly (D, L-lactide) (PLA) nanoparticles were formulated with the benefit of improving its solubility. MATERIALS AND METHODS: TLM-loaded PLA nanoparticles were prepared by emulsion solvent evaporation. The effects of sonication time and polymer:drug ratio on nanoparticle size and drug encapsulation were investigated. TLM-loaded nanoparticles were tested against MCF-7 and MD-AMB-231 breast cancer cell lines for antiproliferative effects. RESULTS: Nanoparticles with mean particle size 272 nm and 79% encapsulation efficiency were obtained. Sustained release TLM nanoparticles (40% in 24 h) decreased cell viability to 45% for MCF-7 cells at 72 h, even at the lowest TLM concentration, indicating better anticancer efficiency than TLM solution. CONCLUSION: TLM nanoparticles could be potential anticancer agents for breast cancer and deserve further studies.

Preparation and in vitro characterization of rosuvastatin calcium incorporated methyl beta cyclodextrin and Captisol® inclusion complexes.

Despite being the most effective hypolipidemic agent, poor physicochemical properties of Rosuvastatin calcium (RCa) remain challenging obstacles in the development of pharmaceutical dosage forms. Inclusion complexes (ICs) of RCa with cyclodextrin (CD) derivatives; methyl-beta-cyclodextrin (M-ß-CD) and sulfobutylether-beta-cyclodextrin (SBE-ß-CD; Captisol®) were formulated by kneading and freeze-drying (lyophilization) methods. Pysicochemical properties of ICs were evaluated by SEM, DSC, XRD, FT-IR, 1H-NMR analyses. Entrapment efficiency (EE), water solubility, in vitro release analyses were also performed. Safety and efficacy of the ICs were analyzed by cytotoxicity and permeation studies on Caco-2 cell lines. Both CDs indicated AL type phase solubility diagrams showing that [1:1] molar ratio. Apparent stability constants (K1:1) were found to be 60.93 M-1 for M-ß-CD and 158.07 M-1 for Captisol®. High EE in the range of 93.50-105.40% was achieved. Molar solubility of RCa was increased 3.7- and 4.1-fold with M-ß-CD and Captisol® ICs, respectively. In vitro release analyses have indicated the equivalence of dissolution profiles for M-ß-CD and Captisol® based ICs to that of pure RCa (f2 > 50). Cytotoxicity studies on Caco-2 cell lines have revealed the safety of ICs for oral use. Permeability studies demonstrated that selected lyophilized F6 formulation has shown the best permeation rate with Papp value of 3.08 × 10-7 cm·s-1. Considering greater water solubility, lower toxicity, high efficiency of complexation as well as, RCa-like permeability and in vitro release behavior at pH 6.8; Captisol® based lyophilized F6 formulation was selected as the best IC to be used in oral dosage forms of RCa.

Exploiting ionisable nature of PEtOx-co-PEI to prepare pH sensitive, doxorubicin-loaded micelles.

AIMS: This study was conducted to evaluate block copolymers containing two different poly(ethyleneimine) (PEI) amounts, as new pH-sensitive micellar delivery systems for doxorubicin. METHODS: Micelles were prepared with block copolymers consisting of poly(2-ethyl-2-oxazoline)-co-poly(ethyleneimine) (PEtOx-co-PEI) and poly(ε-caprolactone) (PCL) as hydrophilic and hydrophobic blocks, respectively. Doxorubicin loading, micelle size, pH-dependent drug release, and in vitro cytotoxicity on MCF-7 cells were investigated. RESULTS: The average size of drug-loaded micelles was under 100 nm and drug loading was between 10.7% and 48.3% (w/w). pH-sensitive drug release was more pronounced (84.7% and 68.9% (w/w) of drug was released at pH 5.0 and pH 7.4, respectively) for the micelles of the copolymer with the lowest PEI amount. The cell viability of doxorubicin-loaded micelles which were prepared by the copolymer with the lowest PEI amount was 28-33% at 72 h. CONCLUSIONS: PEtOx-co-PEI-b-PCL micelles of this copolymer were found to be stable and effective pH-sensitive nano-sized carriers for doxorubicin delivery.

Development of besifloxacin HCl loaded nanofibrous ocular inserts for the treatment of bacterial keratitis: In vitro, ex vivo and in vivo evaluation.

Novel drug delivery systems have emerged to treat bacterial keratitis, an acute infection of the cornea. In this study, besifloxacin HCl loaded insert formulations were designed and investigated in vitro, ex vivo and in vivo for the treatment of bacterial keratitis. Besifloxacin HCl (BH) or BH-hydroxypropyl-beta-cyclodextrin (HP-ß-CD) complex containing poly(caprolactone)/polyethylene glycol (PLC/PEG) fibrous inserts were prepared with an electrospinning method. These fibrous inserts were coated with mucoadhesive polymers such as sodium alginate (SA) or thiolated sodium alginate (TSA). Developed inserts compared to commercially available drug and it was found that coating of the insert surfaces with SA and TSA, increases bioadhesion of the formulations. Insert formulations showed a burst release in the first 2 days followed by a slow-release profile. Ex vivo transport studies showed that HP-ß-CD possessed a drug delivery level close to the commercial drug. Both TSA coated inserts as well as inserts containing HP-ß-CD-drug complex were effectively reducing bacterial keratitis in rabbit eyes upon single-dose application compared to multiple dosing with the commercial drug. Consequently, TSA coated inserts as well as the inserts containing HP-ß-CD-drug complex, may be potential alternatives to conventional market product by reducing the application frequency in the clinic leading to increased patient compliance.

Design of ocular drug delivery platforms and in vitro - in vivo evaluation of riboflavin to the cornea by non-interventional (epi-on) technique for keratoconus treatment.

AIM: Keratoconus is a common and progressive eye disease characterized by thinning and tapering of the cornea. This degenerative eye disease is currently treated in the clinic with an interventional technique ("epi-off") that can cause serious side effects as a result of the surgical procedure. The aim of this project is to design innovative formulations for the development of a riboflavin-containing medicinal product to develop a non-invasive ("epi-on") keratoconus treatment as an alternative to current treatment modalities. METHODS: Nanostructured lipid carriers (NLCs) were successfully loaded with either riboflavin base of riboflavin-5-phosphate sodium and designed with either Stearylamine (positive charge) or Trancutol P (permeation enhancer). In vitro characterization studies, cytotoxicity and permeability studies were performed. Selected formulations and commercial preparations were applied and compared in ex-vivo corneal drug accumulation and transition studies. Furthermore, in vivo studies were performed to assess drug accumulation in the rat cornea and the corneal stability after NLC treatment was investigated via a biomechanical study on isolated rabbit corneas. RESULTS: Both in vitro and ex-vivo as well as in vivo data showed that from the prepared NLC formulations, the most effective formulation was riboflavin-5-phosphate sodium containing NLC with Transcutol P as permeation enhancer. It possessed the highest drug loading content, low accumulation in the cornea but high permeability through the cornea as well as the highest functional performance in corneal crosslinking. CONCLUSION: Topical application of riboflavin-5-phosphate sodium loaded NLC systems designed with permeation enhancer Transcutol P may act as a potential alternative for non-invasive keratoconus treatments.

Physicochemical characterization and pharmacokinetic evaluation of rosuvastatin calcium incorporated solid lipid nanoparticles.

Rosuvastatin calcium (RCa) is a very efficient antihyperlipidemic agent, however, being a BCS class II drug, results in poor oral bioavailability. The present study focused on the enhancement of oral bioavailability of RCa with solid lipid nanoparticles (SLNs). Physicochemical properties of the particles were evaluated by particle size (PS), polidispersity index (PDI), zeta potential (ZP), DSC, FT-IR, XRD, 1H NMR analyses. Entrapment efficiency (EE), drug loading capacity (DL), in vitro release and release kinetics were also analyzed. Safety and efficacy of the formulations were analyzed by cytotoxicity, permeability and pharmacokinetic studies. PS values were ranged between ∼134 and 351 nm with homogenous size distribution (PDI ∼ 0.130-0.33) and ZP data were valued within the range of ∼-17 mV to -41 mV. The SLN2 formulation showed the best cytotoxicity test results and had medium permeability (Papp 5.72 × 10-6 cm sec-1) while pure RCa resulted in low permeability (Papp 3.08 × 10-7 cm sec-1). According to the stability analyses (3 months) 5 ±â€¯3 °C and 25 ±â€¯2 °C were found suitable storage temperatures for SLNs. Pharmacokinetic studies confirmed significant improvement in Cmax (1.4 fold) and AUClast (8.5 fold) by SLNs in comparison with the pure drug indicating the enhanced biopharmaceutical performance of the RCa loaded SLNs.

Preparation, characterization and pharmacokinetic evaluation of rosuvastatin calcium incorporated cyclodextrin-polyanhydride nanoparticles.

Objective: The aim of the study was to formulate, cyclodextrin (CD)-polyanhydride (PA) nanoparticles (CPNs) with rosuvastatin calcium (RCa) in order to enhance the poor oral bioavailability. Methods: CPNs containing RCa/CD complexes were prepared by a modified solvent displacement method and morphological analyses, particle size (PS), polydispersity index (PDI), zeta potential (ZP), encapsulation efficiency (EE), DSC, FT-IR, XRD, 1H-NMR analyses were performed. In vitro release properties, release kinetics, cytotoxicity, in vitro permeability and pharmacokinetic studies were also studied. The stability of the formulations were evaluated during the storage period of 3 months. Results: The physicochemical studies showed that the RCa/CD complexes were well incorporated into CPNs resulted in nanosized particles (215.22 and 189.13 nm) with homogenous size distribution (PDI: 0.203 and 0.182) with relatively high incorporation capacity (76.11 and 68.18%) for the CPN1 and CPN2 formulations respectively. Sustained release of RCa from CPNs were achieved. The cytotoxicity values showed that the safety of the formulations. According to permeability studies, pure RCa had lowest permeability data (3.08 × 10-7 cm⋅s-1 Papp value) while CPNs gained higher permeability data (1.36 × 10-5 and 1.12 × 10-5 cm⋅s-1 Papp values) for the CPN1 and CPN2 formulations respectively. CPN2 formulation was selected for pharmacokinetic studies and analyses results demonstrated that approximately 8-fold relative oral bioavailability enhancement compared to the pure RCa was achieved. Conclusion: Considering the analyses results of the study, CPNs can be regarded as suitable, safe, functional oral delivery systems for RCa with enhanced oral bioavailability.

Discovery of new azoles with potent activity against Candida spp. and Candida albicans biofilms through virtual screening.

Systemic candidiasis is a rampant bloodstream infection of Candida spp. and C. albicans is the major pathogen isolated from infected humans. Azoles, the most common class of antifungals which suffer from increasing resistance, and especially intrinsically resistant non-albicans Candida (NAC) species, act by inhibiting fungal lanosterol 14α-demethylase (CYP51). In this study we identified a number of azole compounds in 1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethanol/ethanone oxime ester structure through virtual screening using consensus scoring approach, synthesized and tested them for their antifungal properties. We reached several hits with potent activity against azole-susceptible and azole-resistant Candida spp. as well as biofilms of C. albicans. 5i's minimum inhibitor concentration (MIC) was 0.125 µg/ml against C. albicans, 0.5 µg/ml against C. krusei and 1 µg/ml against azole-resistant C. tropicalis isolate. Considering the MIC values of fluconazole against these fungi (0.5, 32 and 512 µg/ml, respectively), 5i emerged as a highly potent derivative. The minimum biofilm inhibitor concentration (MBIC) of 5c, 5j, and 5p were 0.5 µg/ml (and 5i was 2 µg/ml) against C. albicans biofilms, lower than that of amphotericin B (4 µg/ml), a first-line antifungal with antibiofilm activity. In addition, the active compounds showed neglectable toxicity to human monocytic cell line. We further analyzed the docking poses of the active compounds in C. albicans CYP51 (CACYP51) homology model catalytic site and identified molecular interactions in agreement with those of known azoles with fungal CYP51s and mutagenesis studies of CACYP51. We observed the stability of CACYP51 in complex with 5i in molecular dynamics simulations.

Development of novel self-assembled polymeric micelles from partially hydrolysed poly(2-ethyl-2-oxazoline)-co-PEI-b-PCL block copolymer as non-viral vectors for plasmid DNA in vitro transfection.

A new efficient, non-viral gene delivery cationic polymeric micellar system was developed by partial hydrolysis of poly(2-ethyl-2-oxazoline) (PEtOx) with two different hydrolysis percentages of PEtOx (30% and 60%) to reduce the disadvantages of the PEI. These self-assemble amphiphilic cationic micelles prepared from poly(2-ethyl-2-oxazoline)30%-co-poly(ethyleneimine)-block-poly(ɛ-caprolactone) (PEtOx30%-co-PEI-b-PCL) (PPP30) and poly(2-ethyl-2-oxazoline) 60%-co-poly(ethyleneimine)-block-poly(ɛ-caprolactone) (PEtOx60%-co-PEI-b-PCL) (PPP60) block copolymers were successfully condensed with pEGFP-C3 plasmid DNA via electrostatic interactions to form micelle/DNA complexes with desirable particle sizes. All formulations showed low critical micelle concentration (CMC) values that means highly stable in serum containing medium. Polymeric micelles were also evaluated for their stability in the presence of serum and nuclease as well as cytotoxicity and transfection efficiency. All our results proved that our novel polymeric micellar system prepared by PPP60 block copolymer offer to be an efficient promising carrier for gene delivery applications. Moreover, these findings contribute to design and development of novel gene vectors with tunable and functionality features and also to reduce the cytotoxicity of PEI by partial hydrolysis of PEtOx an alternative synthesis method to produce linear PEI.

Design and in vitro evaluation of tenofovir-loaded vaginal gels for the prevention of HIV infections.

Infection with the human immunodeficiency virus (HIV) is affecting women disproportionally with increasing incidence rates over the last decades. Tenofovir is one of the most commonly used antiretroviral agents, which belongs to the nucleoside/nucleotide reverse transcriptase inhibitor family, for the prevention of HIV acquisition. In scope of this study, a thermogelling system containing tenofovir-loaded chitosan nanoparticles for the controlled release of tenofovir was developed and characterized. The in vitro release studies have shown that the burst release effect was decreased to 27% with f-TFV CS NPs-Gel. Gelation temperature of developed formulation was found as 26.6 ± 0.2 °C, which provides ease of administration while gelation occurs after the administration to the vagina. The work of adhesion values was used as parameters for comparison of mucoadhesive performance and the mucoadhesion of f-TFV CS NPs-Gel was found as 0.516 ± 0.136 N.s at 37 °C. The biocompatibility of blank formulations was evaluated by cell viability studies using L929 cells, in which Gel + CS NPs formulation was found to be safe with 82.4% and 90.2% cell viability for 1:16 and 1:32 dilutions, respectively. In conclusion, an improved tenofovir containing vaginal gel formulation was successfully developed and evaluated for preventing HIV transmission.

A potential non-invasive glioblastoma treatment: Nose-to-brain delivery of farnesylthiosalicylic acid incorporated hybrid nanoparticles.

New drug delivery systems are highly needed in research and clinical area to effectively treat gliomas by reaching a high antineoplastic drug concentration at the target site without damaging healthy tissues. Intranasal (IN) administration, an alternative route for non-invasive drug delivery to the brain, bypasses the blood-brain-barrier (BBB) and eliminates systemic side effects. This study evaluated the antitumor efficacy of farnesylthiosalicylic acid (FTA) loaded (lipid-cationic) lipid-PEG-PLGA hybrid nanoparticles (HNPs) after IN application in rats. FTA loaded HNPs were prepared, characterized and evaluated for cytotoxicity. Rat glioma 2 (RG2) cells were implanted unilaterally into the right striatum of female Wistar rats. 10days later, glioma bearing rats received either no treatment, or 5 repeated doses of 500µM freshly prepared FTA loaded HNPs via IN or intravenous (IV) application. Pre-treatment and post-treatment tumor sizes were determined with MRI. After a treatment period of 5days, IN applied FTA loaded HNPs achieved a significant decrease of 55.7% in tumor area, equal to IV applied FTA loaded HNPs. Herewith, we showed the potential utility of IN application of FTA loaded HNPs as a non-invasive approach in glioblastoma treatment.

Formulation development, stability and anticancer efficacy of core-shell cyclodextrin nanocapsules for oral chemotherapy with camptothecin.

BACKGROUND: The aim of this study was to design and evaluate hybrid cyclodextrin (CD) nanocapsules intended for the oral delivery of the anticancer agent camptothecin (CPT) in order to maintain drug stability in the body and to improve its eventual bioavailability. For this reason, an amphiphilic cyclodextrin (CD) derivative per-modified on the primary face 6OCAPRO was used as core molecule to form nanocapsules with the nanoprecipitation technique. Nanocapsules were further coated with the cationic polymer chitosan to improve the cellular uptake and interaction with biological membranes through positive surface charge. Nanocapsules were evaluated for their in vitro characteristics such as particle size, zeta potential, drug loading and release profiles followed by cell culture studies with the MCF-7 and Caco-2 cell line evaluating their anticancer efficacy and permeability. The CD nanocapsules were imaged by scanning electron microscopy (SEM). The concentration of CPT entrapped in nanocapsules was determined by reversed phase HPLC. The in vitro release study of CPT was performed with a dialysis bag method under sink conditions mimicking the gastric and intestinal pH. The hydrolytic stability of CPT in nanocapsules was investigated in simulated gastric and intestinal fluids (SGF, SIF). RESULTS: The mean particle sizes of both anionic and cationic CPT-loaded nanocapsules were in the range of 180-200 nm with polydispersity indices lower than 0.400 indicating monodisperse size distribution of nanocapsules with favourable potential for intracellular drug delivery to tumour cells. Surface charges of anionic and cationic nanocapsules were demonstrated as -21 mV and +18 mV, respectively. The stability of CPT in simulated release media, SGF and SIF were maintained suggesting the improved protection of the drug molecule from rapid hydrolysis degradation or gastrointestinal pH in nanocapsule oily core. Furthermore CD nanocapsules showed higher anticancer efficacy than CPT solution against the MCF-7 cell line. Permeation of CPT across Caco-2 cells was found to be 3 fold higher when incorporated in hybrid CD nanocapsules compared with a DMSO solution. CONCLUSION: Oral CD nanocapsules indicating increased oral bioavailability might be a promising strategy to maintain the physiological stability and to improve the oral bioavailability of problematic anticancer drugs such as CPT which may contribute to patient quality of life and drug efficacy in cancer therapy.