A pH- and Bioreducible Cationic Copolymer with Amino Acids and Piperazines for Adenovirus Delivery

Potent therapeutic efficacy of intranasally deliverable paclitaxel modified with pH-sensitive and PEGylated polymeric micelle against glioblastoma

Glioblastoma multiforme (GBM) is the most aggressive and common type of brain tumor. Conventional therapies for GBM, such as surgery or radiotherapy, have shown inadequate therapeutic effect. Similarly, a large fraction of chemotherapeutics are ineffective against GBM due to the blood-brain barrier (BBB) preventing effective delivery of these drugs to the brain. To overcome these obstacles, an intranasally administrable and multifunctional drug-loaded polymeric micelle composed of a pH-sensitive PPCBA-PEI-Arg (PPA) polymer conjugated with PEGylated paclitaxel (PEG-PTX; PPP) was synthesized to treat GBM. PPP was more soluble in an aqueous solution than parental PTX and was more effectively internalized into the GBM cells. Further, PPP elicited a more potent cancer cell killing effect than PTX under physiological pH condition, which was further augmented under the mildly acidic condition that emulated the tumor microenvironment. Intranasal administration of PPP into orthotopic GBM tumor xenograft-bearing mice led to more efficient delivery of the drug to the brain tissues compared to parental PTX delivered via intranasal or intravenous route, thus resulting in superior inhibition of GBM growth. Collectively, these findings demonstrated that intranasal delivery of PTX via pH-sensitive and PEGylated polymeric micelles can be an effective approach for the treatment of aggressive GBM.

Living virus-based nanohybrids for biomedical applications

Living viruses characterized by distinctive biological functions including specific targeting, gene invasion, immune modulation, and so forth have been receiving intensive attention from researchers worldwide owing to their promising potential for producing numerous theranostic modalities against diverse pathological conditions. Nevertheless, concerns during applications, such as rapid immune clearance, altering immune activation modes, insufficient gene transduction efficiency, and so forth, highlight the crucial issues of excessive therapeutic doses and the associated biosafety risks. To address these concerns, synthetic nanomaterials featuring unique physical/chemical properties are frequently exploited as efficient drug delivery vehicles or treatments in biomedical domains. By constant endeavor, researchers nowadays can create adaptable living virus-based nanohybrids (LVN) that not only overcome the limitations of virotherapy, but also combine the benefits of natural substances and nanotechnology to produce novel and promising therapeutic and diagnostic agents. In this review, we discuss the fundamental physiochemical properties of the viruses, and briefly outline the basic construction methodologies of LVN. We then emphasize their distinct diagnostic and therapeutic performances for various diseases. Furthermore, we survey the foreseeable challenges and future perspectives in this interdisciplinary area to offer insights. This article is categorized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Fabrication of zein-based hydrophilic nanoparticles for efficient gene delivery by layer-by-layer assembly

As a natural biological macromolecule, zein has broad application prospects in drug delivery due to its unique self-assembly properties. In this work, zein/sodium alginate (Zein/SA) nanocomposites were prepared by a pH-cycle method, Then Zein/SA/PEI (ZSP) nanocomposites were prepared by efficient layer-by-layer assembly method, ZSP nanocomposite of higher transfection performance was further labeled by folic acid (FA). After characterizing the physicochemical properties of ZSP by various methods, the potential of ZSP as a gene delivery vehicle was explored in vitro. The results showed that ZSP had good dispersibility and stability, the diameter distribution was in the range of 124-203 nm, and it had a typical core-shell structure, which could effectively condensate DNA and protect it from nuclease hydrolysis. ZSP exhibited proton buffering capacity similar to PEI, lower cellular toxicity, lower protein adsorption and erythrocyte hemolysis effect than PEI. ZSP/pDNA complexes could be taken up by cells and exhibited higher transfection efficiency than PEI/DNA complexes at the same weight ratio. The transfection efficiency of the complex in HeLa and 293T cells can be improved by FA labeling, especially in HeLa cells. These results provide new perspective for the design and development of efficient zein-based gene delivery systems.