Polymeric micelles based on a polyaspartamide copolymer for pulmonary delivery of beclomethasone dipropionate

Inhalation therapy allows the administration of drugs used in several pulmonary diseases able to play a local action on the specific site with a more uniform distribution of them. This type of administration presents some limitations, such as the poor solubility of the drug in biological fluids and the presence of mucus on lung tissue that hinders the absorption of the drugs1. To allow efficient administration of drugs in the treatment of asthma and COPD, polymeric micelles based on polyaspartammide (PHEA) copolymer, PHEA-PEG2000-EDA-LA (PPE-LA), containing beclomethasone dipropionate (BDP), a poorly soluble drug in aqueous solution, have been prepared. PHEA-PEG2000- EDA-LA is a amphiphilic copolymer bearing hydrophilic moieties represented by PEG2000 and ethylenediamine (EDA), whose amino groups increase the reactivity of the copolymer versus the subsequent nucleophilic reaction, and a hydrophobic portion represented by lipoic acid (LA), having antioxidant properties, interesting in a possible application of the PPE-LA micelles in asthma treatments, that was partially linked to amino groups of EDA

PEGYLATED POLYASPARTAMIDE\u2013POLYLACTIDE BASED NANOPARTICLES PENETRATING CYSTIC FIBROSIS ARTIFICIAL MUCUS

Here, the preparation of mucus-penetrating nanoparticles for pulmonary administration of ibuprofen in patients with cystic fibrosis is described. A fluorescent derivative of \u3b1,\u3b2-poly(N-2-hydroxyethyl)-D,L-aspartamide is synthesized by derivatization with rhodamine, polylactide, and poly(ethylene glycol), to obtain polyaspartamide 12 polylactide derivatives with different degrees of pegylation. Starting from these copolymers, fluorescent nanoparticles with different poly(ethylene glycol) content, empty and loaded with ibuprofen, showed spherical shape, colloidal size, slightly negative \u3b6 potential, and biocompatibility toward human bronchial epithelial cells. The high surface poly(ethylene glycol) density of fluorescent nanoparticles and poly(ethylene glycol) brush-like conformation assumed on their surface, conferred to pegylated nanoparticles the mucus-penetrating properties, properly demonstrated by assessing their ability to avoid interactions with mucus components and to penetrate cystic fibrosis artificial mucus. Finally, ibuprofen release profile and uptake capacity within human bronchial epithelial cells in the presence of cystic fibrosis artificial mucus showed how these mucus-penetrating nanoparticles could rapidly diffuse through the mucus barrier reaching the mucosal surface, where they could offer a sustained delivery of ibuprofen at the site of disease

Entrapment of an EGFR inhibitor into nanostructured lipid carriers (NLC) improves its antitumor activity against human hepatocarcinoma cells

Background: In hepatocellular carcinoma (HCC), different signaling pathways are de-regulated, and among them, the expression of the epidermal growth factor receptor (EGFR). Tyrphostin AG-1478 is a lipophilic low molecular weight inhibitor of EGFR, preferentially acting on liver tumor cells. In order to overcome its poor drug solubility and thus improving its anticancer activity, it was entrapped into nanostructured lipid carriers (NLC) by using safe ingredients for parenteral delivery. Results: Nanostructured lipid carriers (NLC) carrying tyrphostin AG-1478 were prepared by using the nanoprecipitation method and different matrix compositions. The best system in terms of mean size, PDI, zeta potential, drug loading and release profile was chosen to evaluate the anti-proliferative effect of drug-loaded NLC versus free drug on human hepatocellular carcinoma HA22T/VGH cells. Conclusions: Thanks to the entrapment into NLC systems, tyrphostin AG-1478 shows an enhanced in vitro anti-tumor activity compared to free drug. These finding raises hope of future drug delivery strategy of tyrphostin AG-1478 -loaded NLC targeted to the liver for the HCC treatment

Polyanion-tobramycin nanocomplexes into functional microparticles for the treatment of Pseudomonas aeruginosa infections in cystic fibrosis

AIM: Efficacy of antibiotics in cystic fibrosis (CF) is compromised by the poor penetration through mucus barrier. This work proposes a new 'nano-into-micro' approach, used to obtain a combinatorial effect: achieve a sustained delivery of tobramycin and overcome mucus barrier. METHODS: Mannitol microparticles (MPs) were loaded with a tobramycin polymeric nanocomplex and characterized in presence of CF artificial mucus. RESULTS & DISCUSSION: MPs are able to alter the rheological properties of CF artificial mucus, enhancing drug penetration into it and allowing a prolonged drug release. MPs resulted to be effective in Pseudomonas aeruginosa infections if compared with free tobramycin. CONCLUSION: MPs resulted to be a formulation of higher efficacy, with potential positive implications, as lower required dose, administration frequency, side effects and antibiotic resistance problems

Hepatocyte-targeted fluorescent nanoparticles based on a polyaspartamide for potential theranostic applications

Here, the synthesis of a galactosylated amphiphilic copolymer bearing rhodamine (RhB) moieties and its use for the preparation of polymeric fluorescent nanoparticles for potential applications in therapy and diagnosis are described. To do this, firstly, a fluorescent derivative of alpha,beta-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA) was synthesized by chemical reaction with RhB, and with polylactic acid (PLA), to obtain PHEA-RhB-PLA. Then, the derivatization of PHEA-RhB-PLA with GAL-PEG-NH2 allows obtaining PHEA-RhB-PLA-PEGGAL copolymer, with derivatization degrees in -PLA and -PEG-GAL equal to 1.9 mol% and 4.5 mol%, respectively. Starting from this copolymer, liver-targeted fluorescent nanoparticles were prepared by high pressure homogenizationesolvent evaporation method, and showed nanoscaled size, slightly negative zeta potential and spherical shape. Chemical and enzymatic stability of fluorescent dye covalently linked to the copolymer backbone by ester linkage was demonstrated until 4 days of incubation. Finally, thanks to the covalently-linked fluorescent RhB, it was demonstrated that these galactosylated nanoparticles interact with HepG2 cells that are positive for the asialoglycoprotein receptor (ASGPR), while these do not interact with HeLa cells that are negative for the same receptor, demonstrating the contributor of ASGPR to the internalization process

POLYMERIC FLUORESCENT NANOPARTICLES BASED ON A POLYASPARTAMIDE FOR IMAGING APPLICATIONS: EVALUATION OF GALACTOSE TARGETING ON HEPG2 CELL INTERNALIZATION

In the field of nanomedicine, the use of polymeric fluorescent nanoparticles for in vitro and in vivo imaging is a promising application in order to evaluate passive as well as active targeting strategies [1]. In this work, the synthesis of an amphiphilic galactosylated polylactide-polyaminoacid copolymer bearing rhodamine (RhB) moieties and its use for the preparation of polymeric fluorescent nanoparticles for potential in vitro and in vivo imaging applications are described. To do this, firstly, a fluorescent derivative of α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA) was obtained by chemical reaction of PHEA with RhB. Then, a galactosylated derivative of polyethylene glycol, the O-(2-aminoethyl)-O’-galactosyl polyethylene glycol (GAL-PEG-NH2) was obtained by a reductive amination of lactose with primary amine function of poly(ethylene glycol)bis(amine) (H2N-PEG-NH2) in the presence of sodium cyanoborohydride. The fluorescent galactosylated polylactide-polyaminoacid conjugate was obtained by chemical reaction of PHEA-RhB with polylactic acid (PLA), and subsequent reaction with GAL-PEG-NH2, obtaining PHEA-RhB-PLA-PEG-GAL copolymer [2]. Starting from this copolymer, liver-targeted fluorescent nanoparticles, were successfully prepared by high pressure homogenization– solvent evaporation method [2]. Fluorescenti nanoparticles have nanoscaled size and spherical shape as showed by Dinamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) analyses. Moreover, thanks to the fluorescence given by covalently-linked RhB, by confocal microscopy studies it was demonstrated that these nanoparticles bearing GAL moieties interact with HepG2 cells that are positive for the asialoglycoprotein receptor (ASGP-R), while these do not interact with HeLa cells that are negative for the same receptor, demonstrating the contributor of ASGPR to the internalization process. [1] Vollrath A, S. Schubert, U.S. Schubert, Fluorescence imaging of cancer tissue based on metal-free polimeric nanopaticles - A review, J Mat Chem. 1, 1994 (2013). [2] E.F. Craparo, G. Teresi, M.C. Ognibene, M.P. Casaletto, M.L. Bondì, G. Cavallaro. J Nanoparticle Res. 12, 2629 (2010)

Realization of polyaspartamide-based nanoparticles and in vivo lung biodistribution evaluation of a loaded gucocorticoid after aerosolization in mice

In this study, novel polymeric nanoparticles (NPs) were developed and their potential as carriers for beclomethasone dipropionate (BDP) into the lung after aerosolization was demonstrated by in vivo studies in mice. In particular, these NPs were obtained starting from two polyaspartamide-based copolymers which were synthesized by chemical reaction of a,b-poly(N-2-hydroxyethyl)-DL-asparta-mide (PHEA) and its pegylated derivative (PHEA-PEG2000) with poly(lactic acid) (PLA). To obtain nanosized particles, the high pressure homogenization (HPH)—solvent evaporation method was followed by using an organic phase containing both PHEA-PLA and PHEA-PEG2000-PLA (at a weight ratio equal to 1:1), lactose as cryoprotectant and no surfactant was adopted. PHEA-PLA/PHEA-PEG2000-PLA NPs were characterized by a quite spherical shape, z potential slightly negative, and size lower than 50 and 200 nm, respectively, for empty and BDP-loaded NPs. In vivo biodistribution of BDP and its metabolites in various lung compartments, i.e. bronchoalveolar lavage fluid (BALF), alveolar macrophages (MPG) obtained from BALF, and lung tissue, was carried out at 3 h post-administration in mice by aerosolization of BDP-loaded NPs or free BDP (commercial formulation, Clenil1) at the dose of 0.5 mg/kg BDP. Results demonstrated that BDP entrapped into NPs reached all analyzed lung compartments and were internalized by both alveolar MPG and respiratory epithelial cells, and detected amounts were comparable to those of Clenil-treated mice. Moreover, the entrapment into NPs protects the drug from the enzymatic hydrolysis, allowing a significant lower amount of beclomethasone (BOH) into the lung tissue and BALF than that obtained after Clenil administration