Insights into EPR effect versus lectin-mediated targeted delivery: biodegradable polycarbonate micellar nanoparticles with and without galactose surface decoration

Enhancing cell-scale performance via sustained release of the varicella-zoster virus antigen from a microneedle patch under simulated microgravity

The immune system of astronauts might become weakened in the microgravity environment in space, and the dormant varicella-zoster virus (VZV) in the body might be reactivated, seriously affecting their work and safety. For working in orbit for the long term, there is currently no efficient and durable delivery system of general vaccines in a microgravity environment. Accordingly, based on the previous foundation, we designed, modified, and synthesized a biodegradable and biocompatible copolymer, polyethylene glycol-polysulfamethazine carbonate urethane (PEG-PSCU) that could be mainly adopted to fabricate a novel sustained-release microneedle (S-R MN) patch. Compared with conventional biodegradable microneedles, this S-R MN patch could not only efficiently encapsulate protein vaccines (varicella-zoster virus glycoprotein E, VZV gE) but also further prolong the release time of VZV gE in a simulated microgravity (SMG) environment. Eventually, we verified the activation of dendritic cells by VZV gE released from the S-R MN patch in an SMG environment and the positive bioeffect of activated dendritic cells on lymphocytes using an in vitro lymph node model. This study is of great significance for the exploration of long-term specific immune responses to the VZV in an SMG environment.

Galectin-3: therapeutic targeting in liver disease

INTRODUCTION

The rising incidence of liver diseases is a worldwide healthcare concern. However, the therapeutic options to manage chronic inflammation and fibrosis, the processes at the basis of morbidity and mortality of liver diseases, are very limited. Galectin 3 (Gal-3) is a protein implicated in fibrosis in multiple organs. Several Gal-3 inhibitors are currently in clinical development.

AREAS COVERED

This review describes our current understanding of the role of Gal-3 in chronic liver diseases, with special emphasis on fibrosis. Also, we review therapeutic advances based on Gal-3 inhibition, describing drug properties and their current status in clinical research.

EXPERT OPINION

Currently, the known effects of Gal-3 point to a direct activation of the NLRP3 inflammasome leading to its activation in liver macrophages and activated macrophages play a key role in tissue fibrogenesis. However, more research is needed to elucidate the role of Gal-3 in the different activation pathways, dissecting the intracellular and extracellular mechanisms of Gal-3, and its role in pathogenesis. Gal-3 could be a target for early therapy of numerous hepatic diseases and, given the lack of therapeutic options for liver fibrosis, there is a strong pharmacologic potential for Gal-3-based therapies.

Engineering nanotheranostic strategies for liver cancer

The incidence and mortality of hepatocellular carcinoma have continued to increase over the last few years, and the medicine-based outlook of patients is poor. Given great ideas from the development of nanotechnology in medicine, especially the advantages in the treatments of liver cancer. Some engineering nanoparticles with active targeting, ligand modification, and passive targeting capacity achieve efficient drug delivery to tumor cells. In addition, the behavior of drug release is also applied to the drug loading nanosystem based on the tumor microenvironment. Considering clinical use of local treatment of liver cancer, in situ drug delivery of nanogels is also fully studied in orthotopic chemotherapy, radiotherapy, and ablation therapy. Furthermore, novel therapies including gene therapy, phototherapy, and immunotherapy are also applied as combined therapy for liver cancer. Engineering nonviral polymers to function as gene delivery vectors with increased efficiency and specificity, and strategies of co-delivery of therapeutic genes and drugs show great therapeutic effect against liver tumors, including drug-resistant tumors. Phototherapy is also applied in surgical procedures, chemotherapy, and immunotherapy. Combination strategies significantly enhance therapeutic effects and decrease side effects. Overall, the application of nanotechnology could bring a revolutionary change to the current treatment of liver cancer.

Inulin-Coated Iron Oxide Nanoparticles: A Theranostic Platform for Contrast-Enhanced MR Imaging of Acute Hepatic Failure

The present study introduces a superparamagnetic nanocomposite, Fe-Si-In, as a T2 magnetic resonance imaging (MRI) contrast agent with a core of iron oxide nanoparticles and a nonporous silica inner shell/carboxymethyl inulin outer shell. Due to its core/shell properties, the structure characterization, biocompatibility, and performance in MRI, as well as its potential as a drug delivery system, were thoroughly evaluated. The results have shown that the synthesized nanocomposite possesses excellent biocompatibility and acceptable magnetization (M_s = 20 emu g^-1). It also has the potential to be a nanocarrier for drug delivery purposes, as evidenced by the results of curcumin administration studies. The developed nanocomposite has shown excellent performance in MRI, while the in vitro relaxivity measurements reveal a stronger T2 relaxivity (r₂ = 223.2 ms) compared to the commercial samples available in the market. Furthermore, the in vivo MRI studies demonstrate an excellent contrast between injured livers and normal ones in rats which again upholds the high performance of Fe-Si-In in MRI diagnostics.

Polydopamine and peptide decorated doxorubicin-loaded mesoporous silica nanoparticles as a targeted drug delivery system for bladder cancer therapy

We reported a simple polydopamine (PDA)-based surface modification method to prepare novel targeted doxorubicin-loaded mesoporous silica nanoparticles and peptide CSNRDARRC conjugation (DOX-loaded MSNs@PDA-PEP) for enhancing the therapeutic effects on bladder cancer. Drug-loaded NPs were characterized in terms of size, size distribution, zeta potential, transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) surface area and drug loading content. In vitro drug release indicated that DOX-loaded MSNs@PDA and MSNs@PDA-PEP had similar release kinetic profiles of DOX. The PDA coating well controlled DOX release and was highly sensitive to pH value. Confocal laser scanning microscopy (CLSM) showed that drug-loaded MSNs could be internalized by human bladder cancer cell line HT-1376, and DOX-loaded MSNs@PDA-PEP had the highest cellular uptake efficiency due to ligand-receptor recognition. The antitumor effects of DOX-loaded nanoparticles were evaluated by the MTT assay in vitro and by a xenograft tumor model in vivo, demonstrating that targeted nanocarriers DOX-loaded MSNs@PDA-PEP were significantly superior to free DOX and DOX-loaded MSNs@PDA. The novel DOX-loaded MSNs@PDA-PEP, which specifically recognized HT-1376 cells, can be used as a potential targeted drug delivery system for bladder cancer therapy.

Curcumin-loaded redox response of self-assembled micelles for enhanced antitumor and anti-inflammation efficacy

At present, it has become evident that inflammation plays a critical role in tumor growth; meanwhile, chemotherapeutic agents using nanocarriers have been suggested as a promising strategy in cancer treatment. In this study, novel redox-responsive micelles were prepared from monomethoxy-poly(ethylene glycol)-chitosan-S-S-hexadecyl (C₁₆-SS-CS-mPEG). These micelles were able to carry and deliver drugs into tumor cells. To serve as a control, monomethoxy-poly(ethylene glycol)-chitosan-C-C-hexadecyl (C₁₆-CC-CS-mPEG) was developed in a similar fashion to that used to yield C₁₆-CC-CS-mPEG without a redox-responsive disulfide bond. The cellular uptake mechanisms of both micelles were determined. The efficient intracellular drug release from micelles in MCF-7 cells was further confirmed. Results indicated that curcumin (Cur) could rapidly form C₁₆-SS-CS-mPEG@ Cur micelles when exposed to reducing agents and efficaciously enhance intracellular accumulation. The cytotoxicity assay demonstrated that C₁₆-SS-CS-mPEG@Cur exhibited satisfactory cytotoxicity against MCF-7 cells. Anti-inflammation assay results indicated that C₁₆-SS-CS-mPEG@Cur treatment significantly downregulated tumor necrosis factor (TNF-α) expression and showed good anti-inflammatory effects in tumor microenvironment. Most importantly, antitumor effects in vivo showed satisfactory therapeutic effects with C₁₆-SS-CS-mPEG@Cur. Hence, C₁₆-SS-CS-mPEG@Cur micelles can be useful in tumor therapy.

Biomimetic strategies for targeted nanoparticle delivery

Nanoparticle‐based drug delivery and imaging platforms have become increasingly popular over the past several decades. Among different design parameters that can affect their performance, the incorporation of targeting functionality onto nanoparticle surfaces has been a widely studied subject. Targeted formulations have the ability to improve efficacy and function by positively modulating tissue localization. Many methods exist for creating targeted nanoformulations, including the use of custom biomolecules such as antibodies or aptamers. More recently, a great amount of focus has been placed on biomimetic targeting strategies that leverage targeting interactions found directly in nature. Such strategies, which have been painstakingly selected over time by the process of evolution to maximize functionality, oftentimes enable scientists to forgo the specialized discovery processes associated with many traditional ligands and help to accelerate development of novel nanoparticle formulations. In this review, we categorize and discuss in‐depth recent works in this growing field of bioinspired research.

Facile Construction of pH- and Redox-Responsive Micelles from a Biodegradable Poly(β-hydroxyl amine) for Drug Delivery

Here we demonstrate a type of pH and reduction dual-sensitive biodegradable micelles, which were self-assembled by a cationic polymer in an aqueous solution. Due to tumor cells or tissues showing low pH and high reduction concentration, these micelles possessed specific tumor targetability and maximal drug-release controllability inside tumor cells upon changes in physical and chemical environments, but presented good stability at physiological conditions. CCK-8 assay showed that the DOX-loaded micelles had a similar cytotoxicity for MCF-7 tumor cells as free DOX, and blank micelles had a very low cytotoxicity to the cells. Fluorescent microscopy observation revealed that the drug-loaded micelles could be quickly internalized by endosomes to inhibit cancer cell growth. These results indicated these biodegradable micelles, as a novel and effective pH- and redox-responsive nanocarrier, have a potential to improve drug delivery and enhance the antitumor efficacy.