Heparin-decorated nanostructured lipid carriers of artemether-protoporphyrin IX-transferrin combination for therapy of malaria.

Heme is a prosthetic group of hemoglobin comprising protoporphyrin IX (PPIX) with Fe2+. Studies have shown that modulating heme synthesis pathway in Plasmodium could greatly affect the action mechanism and antimalarial effect of artemisinin and its derivatives. Herein, an intraerythrocytic parasite targeted nanostructured lipid carrier (NLC) was developed for potentiation of artemether (ARM) by combination with PPIX and iron-loaded transferrin (holo-Tf). Firstly, ARM and PPIX were co-loaded into NLCs with high entrapment efficiency. Then, a targeting ligand heparin (HP) was electrostatically adsorbed onto the periphery of NLCs, followed by conjugation with holo-Tf to receive the final formulation Tf-HP-NLC/ARM/PPIX. Tf-HP-NLC/ARM/PPIX exhibited nanoscale particle size (~188 nm) and was relatively stable in simulated gastrointestinal fluids and rat plasma. A sustained drug release characteristic was observed in PBS (pH 7.4). In vitro targeting assay confirmed that Tf-HP-NLC/ARM/PPIX could be specifically and efficiently internalized into intraerythrocytic parasites via HP receptor-meditated endocytosis. Furthermore, due to enhanced intraparasitic accumulation and activated mechanism of ARM, the combinational delivery system Tf-HP-NLC/ARM/PPIX showed increased inhibitory activity against Plasmodium falciparum in culture and enhanced antimalarial effect in Plasmodium berghei-infected murine model, suggesting a promising strategy for development of new therapy based on action mechanism of ARM.

Dynamic Alterations in the Gut Microbiota of Collagen-Induced Arthritis Rats Following the Prolonged Administration of Total Glucosides of Paeony.

Rheumatoid arthritis (RA) is a common autoimmune disease linked to chronic inflammation. Dysbiosis of the gut microbiota has been proposed to contribute to the risk of RA, and a large number of researchers have investigated the gut-joint axis hypothesis using the collagen-induced arthritis (CIA) rats. However, previous studies mainly involved short-term experiments; very few used the CIA model to investigate changes in gut microbiota over time. Moreover, previous research failed to use the CIA model to carry out detailed investigations of the effects of drug treatments upon inflammation in the joints, hyperplasia of the synovium, imbalance in the ratios of Th1/Th2 and Th17/Treg cells, intestinal cytokines and the gut microbiota following long-term intervention. In the present study, we carried out a 16-week experiment to investigate changes in the gut microbiota of CIA rats, and evaluated the modulatory effect of total glucosides of paeony (TGP), an immunomodulatory agent widely used in the treatment of RA, after 12 weeks of administration. We found that taxonomic differences developed in the microbial structure between the CIA group and the Control group. Furthermore, the administration of TGP was able to correct 78% of these taxonomic differences, while also increase the relative abundance of certain forms of beneficial symbiotic bacteria. By the end of the experiment, TGP had reduced body weight, thymus index and inflammatory cell infiltration in the ankle joint of CIA rats. Furthermore, the administration of TGP had down-regulated the synovial content of VEGF and the levels of Th1 cells and Th17 cells in CIA rats, and up-regulated the levels of Th2 cells and Treg cells. The administration of TGP also inhibited the levels of intestinal cytokines, secretory immunoglobulin A (SIgA) and Interferon-γ (IFN-γ). In conclusion, the influence of TGP on dynamic changes in gut microbiota, along with the observed improvement of indicators related to CIA symptoms during 12 weeks of administration, supported the hypothesis that the microbiome may play a role in TGP-mediated therapeutic effects in CIA rats. The present study also indicated that the mechanism underlying these effects may be related to the regulation of intestinal mucosal immunity remains unknown and deserves further research attention.

[Construction of artesunate nanoparticles modified by hyaluronic acid and cell-penetrating peptides and its inhibitory effect on cancer cells in vitro].

Hyaluronic acid (HA) and cell-penetrating peptide (CPP) R6H4-SA modified artesunate nanostructured lipid carrier (HA-R6H4-NLC/ART) for anti-tumor therapy was prepared. The physicochemical properties and in vitro drug release of HA-R6H4-NLC/ART were evaluated, and the uptake and cytotoxicity of liver cancer HepG2 cells were studied. The results showed that HA-R6H4-NLC/ART was spherical like in appearance, and the average particle size was about 160 nm. In vitro release experiments showed that the drug delivery system had sustained release characteristics. Cell results showed that, in slightly acidic environment, pH sensitive CPP R6H4-SA mediated cellular uptake of nanoparticles was significantly higher than that of non-sensitive peptide R8-SA. Meanwhile, HA-R6H4-NLC/ART had a targeting effect on HepG2 cells, and the HA receptor saturation experiment showed that the endocytosis of HA-R6H4-NLC/ART was mediated by the HA receptor on the cell surface. As compared with the unmodified or R6H4-SA single modified group, HA and R6H4-SA co-modified HA-R6H4-NLC/ART significantly improved the cell uptake and had a stronger anti-tumor effect under the conditions of the slightly acid environment and hyaluronidase degradation. The above results showed that hyaluronic acid and CPP R6H4-SA co-modified artesunate nanostructured lipid carrier, which can effectively identify and penetrate the tumor cell membrane into the cell, is a potentially efficient targeting delivery system for anti-tumor drugs.

Free paclitaxel-loaded E-selectin binding peptide modified micelle self-assembled from hyaluronic acid-paclitaxel conjugate inhibit breast cancer metastasis in a murine model.

The present work seeks to construct a nanovehicle for the efficient suppression of breast cancer metastasis through targeting E-selectin on tumor vascular endothelial cells and hyaluronic acid-receptor on tumor cells. Herein, a new ligand-PEG-lipid conjugate, E-selectin binding peptide-polyethene glycol-1-octadecylamine (Esbp-PEG-OA), was used as the targeting molecule of micelle self-assembled form hyaluronic acid-paclitaxel (HA-PTX) conjugate. When loaded with free PTX, the micelles (Esbp-HA-PTX/PTX) exhibited nanoscale particle size with high drug-loading capacity (up to 31.5%). In vitro release study showed that the conjugated and entrapped PTX released simultaneously. Cellular uptake of micelles confirmed that Esbp-HA-PTX micelles could be specifically and efficiently internalized into E-selectin expressing human umbilical vein endothelial cells (HUVEC) and 4T1 breast cancer cells via receptor-meditated endocytosis. In vitro cytotoxicity assay further revealed that Esbp-HA-PTX/PTX micelles significantly improved the selectivity of PTX for killing the two cell types compared with PTX solution formulation. More importantly, Esbp-HA-PTX micelles raised the accumulation of payload in tumor through targeting two cell types in the tumor microenvironment simultaneously, resulting in marked in vivo inhibition of tumor growth, intratumoral microvessel density and metastasis, and decreased systemic toxicity over solution formulation. Overall, Esbp-HA-PTX/PTX micelle is promising in therapy of breast cancer metastasis.