Multifunctional nanomedicines with active targeting and stimuli-responsive drug release function utilizing pathophysiological features of the disease are regarded as an effective strategy for treatment of rheumatoid arthritis (RA). Under the inflammatory environment of RA, activated macrophages revealed increased expression of folate receptor and elevated intracellular reactive oxygen species (ROS) level. In this study, we successfully conjugated folate to polyethylene glycol 100 monostearate as film-forming material and further prepared methotrexate (MTX) and catalase (CAT) co-encapsulated liposomes, herein, shortened to FOL-MTX&CAT-L, that could actively target to activated macrophages. Thereafter, elevated intracellular hydrogen peroxide, the main source of ROS, diffused into liposomes and encapsulated CAT catalyzed the decomposition of hydrogen peroxide into oxygen and water. Continuous oxygen-generation inside liposomes would eventually disorganize its structure and release the encapsulated MTX. We characterized the in vitro drug release, cellular uptake and cytotoxicity studies as well as in vivo pharmacokinetics, biodistribution, therapeutic efficacy and safety studies of FOL-MTX&CAT-L. In vitro results revealed that FOL-MTX&CAT-L possessed sufficient ROS-sensitive drug release, displayed an improved cellular uptake through folate-mediated endocytosis and exhibited a higher cytotoxic effect on activated RAW264.7 cells. Moreover, in vivo results showed prolonged blood circulation time of PEGylated liposomes, enhanced accumulation of MTX in inflamed joints of collagen-induced arthritis (CIA) mice, reinforced therapeutic efficacy and minimal toxicity toward major organs. These results imply that FOL-MTX&CAT-L may be used as an effective nanomedicine system for RA treatment.

Mitoxantrone (MTO) is a potent drug used to treat breast cancer; however, efforts to expand its clinical applicability have been restricted because of its high risk for cardiotoxicity. In this study, we successfully conjugated MTO or folic acid (FA) to a synthesized D-α-tocopheryl polyethylene glycol 2000 succinate (TPGS2k), herein, shortened to MCT and FCT, respectively. The two produced conjugates could self-assemble to form MCT micelles or MCT/FCT mixed micelles (FMCT) aiming to lower systemic toxicity, enhance entrapment efficiency, and provide a platform for targeted delivery. Moreover, these micellar materials showed a significantly low CMC and could be used to load MTO. The diameters of MTO-loaded micelles (MTO-MCT and MTO-FMCT) were less than 100 nm with a negative zeta potential. We further characterized the pH-responsive drug release of MTO-MCT and MTO-FMCT and then assessed their cellular uptake and antitumor efficacy in human breast cancer cell lines (MCF-7) via confocal microscopy, flow cytometry, and cytotoxicity studies. All the results revealed that both MTO-MCT and MTO-FMCT increased drug loading and entrapment efficiency and possessed sufficient pH-sensitive release. Additionally, MTO-FMCT displayed an improved uptake through folate-mediated endocytosis, resulting in a higher cytotoxic effect on MCF-7 cells compared with that of MTO-MCT. Meanwhile, both MTO-MCT and MTO-FMCT exhibited a low toxicity on hCMEC/D3 normal cells. More importantly, pharmacokinetic study demonstrated that, in comparison with free MTO injection, MTO-MCT and MTO-FMCT, respectively, achieved half-lives 11.5 and 13 times longer and a 9.7- and 5.8-fold increase in AUC. In vivo, both MTO-MCT and MTO-FMCT formulations significantly prolonged the survival time of MCF-7 tumor-bearing mice and had a better efficacy/toxicity ratio. Promisingly, MTO-FMCT micelles remarkably increased MTO accumulation in tumors in vivo, induced higher tumor cell apoptosis, and showed lower toxicity toward major organs. These results imply that MTO-FMCT may be used as a potential drug delivery system for breast cancer targeted therapy.

Chemically engineered nanomaterials have been extensively used in early tumor detection and cancer therapy. Despite the promises shown, some chemical or exogenous nature have hindered their application due to their...

Abstract. The aims of this study were to enhance the solubility and dissolution rate of nimodipine (ND) by preparing the inclusion complexes of ND with sulfobutylether-b-cyclodextrin (SBE-β-CD) and 2-hydroxypropyl-b-cyclodextrin (HP-β-CD) and to study the effect of the preparation method on the in vitro dissolution profile in different media (0.1 N HCl pH 1.2, phosphate buffer pH 7.4, and distilled water). Thus, the inclusion complexes were prepared by kneading, coprecipitation, and freeze-drying methods. Phase solubility studies were conducted to characterize the complexes in the liquid state. The inclusion complexes in the solid state were investigated with differential scanning calorimetry (DSC), Xray diffractometry (X-RD), and Fourier transform infrared spectroscopy (FT-IR). Stable complexes of ND/SBE-β-CD and ND/HP-β-CD were formed in distilled water in a 1:1 stoichiometric inclusion complex as indicated by an A L -type diagram. The apparent stability constants (Ks) were 1334.4 and 464.1 M −1 for ND/SBE-β-CD and ND/HP-β-CD, respectively. The water-solubility of ND was significantly increased in an average of 22-and 8-fold for SBE-β-CD and HP-β-CD, respectively. DSC results showed the formation of true inclusion complexes between the drug and both SBE-β-CD and HP-β-CD prepared by the kneading method. In contrast, crystalline drug was detectable in all other products. The dissolution studies showed that all the products exhibited higher dissolution rate than those of the physical mixtures and ND alone, in all mediums. However, the kneading complexes displayed the maximum dissolution rate in comparison with drug and other complexes, confirming the influence of the preparation method on the physicochemical properties of the products.