GE11 peptide modified and reduction-responsive hyaluronic acid-based nanoparticles induced higher efficacy of doxorubicin for breast carcinoma therapy.

Novel breast carcinoma dual-targeted redox-responsive nanoparticles (NPs) based on cholesteryl-hyaluronic acid conjugates were designed for intracellular delivery of the antitumor drug doxorubicin (DOX). A series of reduction-responsive hyaluronic acid derivatives grafted with hydrophobic cholesteryl moiety (HA-ss-Chol) and GE11 peptide conjugated HA-ss-Chol (GE11-HA-ss-Chol) were synthesized. The obtained conjugates showed attractive self-assembly characteristics and high drug loading capacity. GE11-HA-ss-Chol NPs were highly stable under conditions mimicking normal physiological conditions, while showing a fast degradation of the vehicle's structure and accelerating the drug release dramatically in the presence of intracellular reductive environment. Furthermore, the cellular uptake assay confirmed GE11-HA-ss-Chol NPs were taken up by MDA-MB-231 cells through CD44- and epidermal growth factor receptor-mediated endocytosis. The internalization pathways of GE11-HA-ss-Chol NPs might involve clathrin-mediated endocytosis and macropinocytosis. The intracellular distribution of DOX in GE11-HA-ss-Chol NPs showed a faster release and more efficient nuclear delivery than the insensitive control. Enhanced in vitro cytotoxicity of GE11-HA-ss-Chol DOX-NPs further confirmed the superiority of their dual-targeting and redox-responsive capacity. Moreover, in vivo imaging investigation in MDA-MB-231 tumor-bearing mice confirmed that GE11-HA-ss-Chol NPs labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindotricarbocyanine iodide, a near-infrared fluorescence dye, possessed a preferable tumor accumulation ability as compared to the single-targeting counterpart (HA-ss-Chol NPs). The antitumor efficacy showed an improved therapy efficacy and lower systemic side effect. These results suggest GE11-HA-ss-Chol NPs provide a good potential platform for antitumor drugs.

Hepatocellular carcinoma dually-targeted nanoparticles for reduction triggered intracellular delivery of doxorubicin.

Hepatocellular carcinoma (HCC) dual targeted stimuli responsive nanoparticles (NPs) for intracellular delivery of doxorubicin (DOX) were developed based on a reduction cleavable hyaluronic acid-glycyrrhetinic acid conjugate (HA-Cyst-GA). HA-Cyst-GA conjugate readily formed NPs in aqueous milieu and exhibited a high drug loading capacity (33.9%). The NPs redox responsiveness evaluation showed a tendency to lose their structural integrity in response to a reductive stimulus while remaining stable at physiological conditions, and that drug release was dramatically accelerated in presence of an intracellular level of glutathione. Moreover, cellular uptake studies highlighted the affinity of hepatoma cells (HepG2) toward the NPs as compared to breast cancer cells (MDA-MB-231). HA-Cyst-GA DOX-NPs displayed an increased cytotoxic potency over their non-responsive counterparts and free DOX with IC50 of 5.75, 9.33 and 10.23µg/mL, respectively. CLSM observations showed that HA-Cyst-GA DOX-NPs mediated a faster intracellular release and nuclear delivery of DOX as compared to the insensitive control. In vivo imaging study performed on H22 tumor bearing mice revealed a selective accumulation of DiR labeled NPs in the tumor and liver upon systemic administration. The antitumor efficacy was evaluated in HepG2 tumor xenograft model. Overall HA-Cyst-GA NPs appear as a potential HCC targeted intracellular delivery platform for DOX.

Combination of ß-cyclodextrin inclusion complex and self-microemulsifying drug delivery system for photostability and enhanced oral bioavailability of methotrexate: novel technique.

In the present study, we prepared an inclusion complex of methotrexate (MTX) with ß-cyclodextrin (ß-CD) in order to decrease its photosensitivity and enhance its aqueous solubility. Then we incorporated this inclusion complex in a self-microemulsifying drug delivery system (SMEDDS) overall to increase its oral bioavailability. The inclusion complex has been prepared by freeze drying method and characterized by differential scanning calorimetry (DSC), ultraviolet (UV), and infrared (IR) spectroscopy assays. The proper molecular ratio of MTX/ß-CD was found to be of 1:7, and the water-solubility of MTX was increased in an average of 10-fold. The photostability studies showed that the MTX became stable on exposure to light. Construction of pseudoternary diagrams were investigated to prepare a MTX/ß-CD inclusion complex loaded SMEDDS which was characterized by measuring the particle size and the zeta-potential. The optimum formulation of SMEDDS was a system consisting of ethyl oleate, tween 80, and propylene glycol with a mean droplet size of 39.42 nm. In vitro drug release in different pH media showed that the release profile of MTX from the MTX/ß-CD loaded SMEDDS was influenced by the pH of the release medium and presented the characteristics of a sustained release profile. Finally, in-vivo studies showed an enhancement of the bioavailability of MTX from the MTX/ß-CD loaded SMEDDS form of 1.57-fold. We concluded that the ß-CD inclusion complex loaded SMEDDS improved the chemical and physiological properties of MTX and could be a promising means for the delivery of MTX and other unstable and lipophilic drugs by oral route.