Biodegradable Polymeric Nanoparticles for Tumor-Selective Tamoxifen Delivery: In Vitro and in Vivo Studies

2004 ◽  
Vol 845 ◽  
Author(s):  
Dinesh B. Shenoy ◽  
Jugminder S. Chawla ◽  
Mansoor M. Amiji

1. ABSTRACT: This study was performed to evaluate the in-vitro and in-vivo tumor-cellular uptake and biodistribution pattern of tamoxifen when administered intravenously as a simple solution and upon encapsulation into biodegradable, surface-modified poly(ε-caprolactone) (PCL) nanoparticles. PCL (MW ∼ 15, 000) nanoparticles were prepared by the solvent displacement method and characterized for particle size/charge and surface morphology (by scanning electron microscopy). We investigated the nanoparticle-surface modification potential of the hydrophilic stabilizer (Pluronic® F-68 and F-108) employed during the preparation by electron spectroscopy for chemical analysis (ESCA). Quantitative in-vitro cellular uptake of tritiated (3H) tamoxifen in solution form and as nanoparticulate formulation was assessed in MCF-7 breast cancer cells. In-vivo biodistribution studies for the same formulations were carried out in Nu/Nu mice bearing MDA-MB-231 human breast carcinoma xenograft. Spherical nanoparticles having positive zeta potential (∼25 mV) were obtained in the size range of 200-300 nm. Pluronics (both F-68 and F-108), the triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) induced surface hydrophilization of the nanoparticles via adsorption as evident by ESCA. Nanoparticulate formulations of tamoxifen achieved higher intracellular concentrations when exposed at therapeutic concentrations to tumor cells in-vitro compared to solutions. The in-vivo biodistribution studies carried out in nude mice bearing experimental breast tumor suggested increased tumor concentrations for the drug administered as nanoparticulate formulations besides longer retention times within tumor mass. This type of delivery system is expected to provide better therapeutic benefit by dual means: preferential concentration within the tumor mass via enhanced permeation and retention pathway, and; subsequent controlled release, thus maintaining the local drug concentration for longer periods of time to achieve maximal cell-kill.

2006 ◽  
Vol 6 (9) ◽  
pp. 3296-3302 ◽  
Author(s):  
C. Lecaroz ◽  
C. Gamazo ◽  
M. J. Blanco-Prieto

Brucellosis is a worldwide zoonosis caused by different species of the genus Brucella. The intracellular localisation of this pathogen, particularly in macrophages, renders treatment difficult since most antibiotics known to be efficient in vitro do not actively pass through cellular membranes. As alternative to current treatment, polymeric drug delivery systems containing gentamicin have been developed. These particulate carriers target the drug into the mononuclear-phagocytic system, where the pathogen resides that will allow intracellular accumulation of the antibiotic after particle degradation. Besides, particle uptake may induce macrophage activation, increasing the production of reactive oxygen intermediates, involved in host defense against the intracellular pathogen. The aim of the present work was to study the suitability of polymeric nanoparticles for gentamicin entrapment in view to treat brucellosis. Different poly(lactide-co-glycolide) PLGA polymers were used to formulate the nanoparticles containing gentamicin by a water-oil-water solvent evaporation method. Furthermore, in vitro macrophage activation upon nanoparticles phagocytosis and in vivo distribution of the nanocarriers in the target organs for Brucella (liver and spleen) were also studied. The nanoparticle sizes were below 350 nm, the gentamicin encapsulation efficiency depended on the polymer type used for their preparation and the in vitro release of the antibiotic exhibited a continuos pattern (PLGA 502H). PLGA 502H nanoparticles were the most suitable due to the highest entrapment and the most sustained release. The nanoparticles were successfully phagocyted by a J774 murine monocytes cell line and biodistribution studies in mice after intravenous administration of the delivery systems revealed that the particles reached the target organs of Brucella (liver and spleen). All together, these results indicate that the nanocarriers described in this work may be suitable as gentamicin delivery system to control brucellosis.


2020 ◽  
Vol 21 (18) ◽  
pp. 6597
Author(s):  
Chao-Cheng Chen ◽  
Yang-Yi Chen ◽  
Yi-Hsuan Lo ◽  
Ming-Hsien Lin ◽  
Chih-Hsien Chang ◽  
...  

Malignant melanoma is the most harmful type of skin cancer and its incidence has increased in this past decade. Early diagnosis and treatment are urgently desired. In this study, we conjugated picolinamide/nicotinamide with the pharmacophore of 131I-MIP-1145 to develop 131I-iodofluoropicolinamide benzamide (131I-IFPABZA) and 131I-iodofluoronicotiamide benzamide (131I-IFNABZA) with acceptable radiochemical yield (40 ± 5%) and high radiochemical purity (>98%). We also presented their biological characteristics in melanoma-bearing mouse models. 131I-IFPABZA (Log P = 2.01) was more lipophilic than 131I-IFNABZA (Log P = 1.49). B16F10-bearing mice injected with 131I-IFNABZA exhibited higher tumor-to-muscle ratio (T/M) than those administered with 131I-IFPABZA in planar γ-imaging and biodistribution studies. However, the imaging of 131I-IFNABZA- and 131I-IFPABZA-injected mice only showed marginal tumor uptake in A375 amelanotic melanoma-bearing mice throughout the experiment period, indicating the high binding affinity of these two radiotracers to melanin. Comparing the radiation-absorbed dose of 131I-IFNABZA with the melanin-targeted agents reported in the literature, 131I-IFNABZA exerts lower doses to normal tissues on the basis of similar tumor dose. Based on the in vitro and in vivo studies, we clearly demonstrated the potential of using 131I-IFNABZA as a theranostic agent against melanoma.


Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 288 ◽  
Author(s):  
Ma Rie Kim ◽  
Teng Feng ◽  
Qian Zhang ◽  
Ho Yin Edwin Chan ◽  
Ying Chau

Combination therapy is a promising form of treatment. In particular, co-treatment of P3 and QBP1 has been shown to enhance therapeutic effect in vivo in treating polyglutamine diseases. These peptide drugs, however, face challenges in clinical administration due to poor stability, inability to reach intracellular targets, and lack of method to co-deliver both drugs. Here we demonstrate two methods of co-encapsulating the peptide drugs via polymer poly(ethylene glycol)-block-polycaprolactone (PEG-b-PCL) based nanoparticles. Nanoparticles made by double emulsion were 100–200 nm in diameter, with drug encapsulation efficiency of around 30%. Nanoparticles made by nanoprecipitation with lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1′-rac-glycerol) (POPG) were around 250–300 nm in diameter, with encapsulation efficiency of 85–100%. Particles made with both formulations showed cellular uptake when decorated with a mixture of peptide ligands that facilitate endocytosis. In vitro assay showed that nanoparticles could deliver bioactive peptides and encapsulation by double emulsion were found to be more effective in rescuing cells from polyglutamine-induced toxicity.


2014 ◽  
Vol 473 (1-2) ◽  
pp. 384-394 ◽  
Author(s):  
Tahir Khuroo ◽  
Devina Verma ◽  
Sushama Talegaonkar ◽  
Santwana Padhi ◽  
Amulya K. Panda ◽  
...  

Vaccines ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 212 ◽  
Author(s):  
Giulia Anderluzzi ◽  
Gustavo Lou ◽  
Simona Gallorini ◽  
Michela Brazzoli ◽  
Russell Johnson ◽  
...  

messenger RNA (mRNA)-based vaccines combine the positive attributes of both live-attenuated and subunit vaccines. In order for these to be applied for clinical use, they require to be formulated with delivery systems. However, there are limited in vivo studies which compare different delivery platforms. Therefore, we have compared four different cationic platforms: (1) liposomes, (2) solid lipid nanoparticles (SLNs), (3) polymeric nanoparticles (NPs) and (4) emulsions, to deliver a self-amplifying mRNA (SAM) vaccine. All formulations contained either the non-ionizable cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) or dimethyldioctadecylammonium bromide (DDA) and they were characterized in terms of physico-chemical attributes, in vitro transfection efficiency and in vivo vaccine potency. Our results showed that SAM encapsulating DOTAP polymeric nanoparticles, DOTAP liposomes and DDA liposomes induced the highest antigen expression in vitro and, from these, DOTAP polymeric nanoparticles were the most potent in triggering humoral and cellular immunity among candidates in vivo.


2021 ◽  
Author(s):  
Jessica Bratt

<p>The spread of antibiotic resistance and the emergence of multi-drug resistant bacteria is a major threat to public health. This study investigated a unique cytosine rich DNA structure, the i-Motif to deliver soluble Ag+ as a novel antimicrobial agent (AgiMs). AgiMs were evaluated in vitro against P. aeruginosa and A. baumannii strains. AgiMs displayed significant antibacterial activity against both P. aeruginosa and A. baumannii (median MIC: 0.875 µM and 0.75 µM, respectively) by rapid, bactericidal and concentration-dependent effect. Low concentrations of AgiMs showed efficacy against PAO1 20-h biofilms, resulting in 57% reduction in biomass (5 x MIC). A single dose of AgiMs extended survival of G. Mellonella larvae, with the therapeutic benefit paralleled in the reduction of internal bacterial load. Synergistic interactions were observed with the combination of AgiMs and tobramycin, a common antibiotic used to treat P. aeruginosa infections; indicating the potential for AgiMs to reinstate the potency of current antibiotics. This silver-based agent might be an alternative to the failing antibiotic regimes for MDR resistant infections. Further in vitro and in vivo studies are warranted to confirm the therapeutic potential. </p>


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e14053-e14053
Author(s):  
Masayuki Hiraki ◽  
Caining Jin ◽  
Maroof Alam ◽  
Takahiro Maeda ◽  
Masaru Murata ◽  
...  

e14053 Background: Aberrant expression of MCL-1 and BFL-1, the pro-survival members of the Bcl-2 family, is a major cause of drug resistance in human cancers. Mucin 1 (MUC1) is a heterodimeric oncoprotein that is aberrantly expressed in most human carcinomas. Notably, there is no known relationship between the oncogenic MUC1 C-terminal subunit (MUC1-C) and these anti-apoptotic proteins. Methods: MUC1-C was targeted in breast, lung and colon cancer cells by a stable shRNA, a tetracycline-inducible shRNA, or a pharmacologic peptide inhibitor GO-203. MCL-1 was inhibited by siRNA or the MS-1 peptide. In vitro and in vivo studies were conducted using our polymeric nanoparticles (NPs) for intracellular delivery of peptide cargos. Cells were selected for resistance to ABT-737 or ABT-263, which target BCL-2, BCL-XL and BCL-w, but not MCL-1 and BFL-1. Results: Targeting MCL-1 with MS-1/NPs inhibited the survival of parental cancer cells in vitro and in vivo, and was associated with upregulation of BFL-1 levels. In addition, MS-1/NPs treatment had limited effects on ABT-resistant cells because of increased BFL-1 expression. Importantly, we found that targeting MUC1-C is associated with suppression of both MCL-1 and BFL-1. Mechanistically, MUC1-C (i) stabilizes MCL-1 by activating the MEK→ERK and PI3K→AKT pathways, and (ii) induces BFL-1 through the NF-κB p65 pathway. Treatment with GO-203/NPs suppressed proliferation of parental and ABT-resistant cells. In addition, we show that combining GO-203 with ABT-737 is synergistic in inhibiting survival of parental and ABT-resistant cells. Conclusions: These findings demonstrate that targeting MUC1-C with GO-203/NPs is a potential strategy for abrogating MCL-1- and BFL-1-mediated resistance.


Sign in / Sign up

Export Citation Format

Share Document