A guanylurea-functionalized conjugated polymer enables RNA interference in ex vivo human airway epithelium

Cationic Polymers as Transfection Reagents for Nucleic Acid Delivery

Nucleic acid therapy can achieve lasting and even curative effects through gene augmentation, gene suppression, and genome editing. However, it is difficult for naked nucleic acid molecules to enter cells. As a result, the key to nucleic acid therapy is the introduction of nucleic acid molecules into cells. Cationic polymers are non-viral nucleic acid delivery systems with positively charged groups on their molecules that concentrate nucleic acid molecules to form nanoparticles, which help nucleic acids cross barriers to express proteins in cells or inhibit target gene expression. Cationic polymers are easy to synthesize, modify, and structurally control, making them a promising class of nucleic acid delivery systems. In this manuscript, we describe several representative cationic polymers, especially biodegradable cationic polymers, and provide an outlook on cationic polymers as nucleic acid delivery vehicles.

Carbamoylated Guanidine-Containing Polymers for Non-Covalent Functional Protein Delivery in Serum-Containing Media

Despite the high potential of controlling cellular processes and treating various diseases by intracellularly delivered proteins, current delivery systems exhibit poor efficiency due to poor serum stability, cellular entry, and cytosolic availability of proteins. Here, we report a novel functional group, phenyl carbamoylated guanidine (Ph-CG), that greatly enhances the delivery efficiency to various types of cells. Owing to the substantially lowered pK_a , the hydrophobic Ph-CG offers optimized inter-macromolecular interactions via enhanced hydrogen-bonding and hydrophobic interactions. The coplanarity of Ph-CG also leads to the better intracellular entry of protein complexes. Intracellularly delivered apoptosis-inducing enzymes and antibodies significantly induce cell viability inhibitions in a serum-containing medium. The newly developed Ph-CG can be introduced to various existing carriers, leading to the realization of future therapeutic protein delivery.

Gene therapy strategies for rare monogenic disorders with nuclear or mitochondrial gene mutations

Rare monogenic disorders are a group of single-gene-mutated diseases that have a low incidence rate (less than 0.5‰) and eventually lead to patient disability and even death. Due to the relatively low number of people affected, these diseases typically fail to attract a great deal of commercial investment and research interest, and the affected patients thus have unmet medical needs. Advances in genomics biology, gene editing, and gene delivery can now offer potentially effective options for treating rare monogenic diseases. Herein, we review the application of gene therapy strategies (traditional gene therapy and gene editing) against various rare monogenic diseases with nuclear or mitochondrial gene mutations, including eye, central nervous system, pulmonary, systemic, and blood cell diseases. We summarize their pathologic features, address the barriers to gene delivery for these diseases, discuss available therapies in the clinic and in clinical trials, and sum up in-development gene delivery systems for various rare monogenic disorders. Finally, we elaborate the possible directions and outlook of gene therapy for rare monogenic disorders.

More attention on glial cells to have better recovery after spinal cord injury

Functional improvement after spinal cord injury remains an unsolved difficulty. Glial scars, a major component of SCI lesions, are very effective in improving the rate of this recovery. Such scars are a result of complex interaction mechanisms involving three major cells, namely, astrocytes, oligodendrocytes, and microglia. In recent years, scientists have identified two subtypes of reactive astrocytes, namely, A1 astrocytes that induce the rapid death of neurons and oligodendrocytes, and A2 astrocytes that promote neuronal survival. Moreover, recent studies have suggested that the macrophage polarization state is more of a continuum between M1 and M2 macrophages. M1 macrophages that encourage the inflammation process kill their surrounding cells and inhibit cellular proliferation. In contrast, M2 macrophages promote cell proliferation, tissue growth, and regeneration. Furthermore, the ability of oligodendrocyte precursor cells to differentiate into adult oligodendrocytes or even neurons has been reviewed. Here, we first scrutinize recent findings on glial cell subtypes and their beneficial or detrimental effects after spinal cord injury. Second, we discuss how we may be able to help the functional recovery process after injury.

DyMnO3/Fe2O3 nanocomposites: simple sol-gel auto-combustion technique and photocatalytic performance for water treatment

Recently, nanocomposite photocatalysts based on semiconductors have drawn consideration due to their suitable bandgap. Combination of tow of several semiconductors can slow down the electron-hole recombination. For this purpose, we have introduced DyMnO₃/Fe₂O₃ nanocomposite as a novel and efficient catalyst for water purification. For this regard, DyMnO₃/Fe₂O₃ nanocomposite has been fabricated by a simple and green sol-gel auto-combustion technique. The impact of calcination temperature, time, and types of fuel was investigated on morphology, structure, and purity of the products. The samples were identified by XRD, FTIR, FESEM, HRTEM, BET, and DRS. The bandgap was calculated by DRS to be 3.20 and 3.28 eV for Fe₂O₃ and DyMnO₃. Due to the appropriate bandgap, DyMnO₃/Fe₂O₃ degraded 80% of methylene blue under UV light. The future aspects of the DyMnO₃/Fe₂O₃ application can be applied in thermoelectric materials, solid fuel cells, electrochemical gas sensors, and electrochemical biosensors.

Mucus-penetrating PEGylated polysuccinimide-based nanocarrier for intravaginal delivery of siRNA battling sexually transmitted infections

Intravaginal delivery of siRNA for prevention of sexually transmitted infections faces obstacles such as the acidic environment and vaginal mucus barrier. To achieve effective protection and delivery of siRNA, we developed a polysuccinimide (PSI)-based nanocarrier (PSI-PEG-API-PMA, PPAP) by conjugating methoxy polyethylene glycol amine (Me-PEG-NH₂, Mw 5000), 1-(3-aminopropyl)imidazole (API), and 1-pyrenemethylamine hydrochloride (PMA) to PSI. PPAP demonstrated a spherical self-assembled nanostructure before and after encapsulation of a model siRNA. Variable electrostatic interaction between API and siRNA at acidic vs. neutral pH accomplished significantly lower burst release at pH 4.2 (4 ± 1%) than pH 7.0 (26 ± 5%) within 1 h. PEGylation enabled siRNA-PPAP to achieve higher mucus penetration efficiency (64 ± 17%) than free siRNA (27 ± 5%) for 24 h. Moreover, in vitro study showed minimal toxicity, successful internalization of siRNA-PPAP in HeLa cells and improved gene knockdown (97.5 ± 0.4%). Overall, PPAP is promising for developing preventative treatments for battling sexually transmitted infections.

Fabrication of chitosan/polyvinylpyrrolidone hydrogel scaffolds containing PLGA microparticles loaded with dexamethasone for biomedical applications

One of the most effective approaches for treatment of chronic rhinosinusitis is the use of hydrogel scaffolds with the sustained release of a given required drug. With this in mind, first, we synthesized and characterized poly (lactide-co-glycolide) (PLGA) micro and nano particles loaded with dexamethasone (DEX). We observed a 7-day release of DEX from nanoparticles, while the microparticles showed a 22-day release profile. Due to their slower rate of release, the PLGA microparticles loaded with DEX (PLGADEX microparticles) were specifically chosen for this study. As a second step, chitosan/polyvinylpyrrolidone (PVP) based hydrogels were prepared in various weight ratios and the PLGADEX microparticles were optimized in their structure based on variable gelation times. The morphological studies showed PLGADEX microparticles homogenously dispersed in the hydrogels. Moreover, the effect of weight ratio in the presence and absence of optimum percentage of PLGADEX microparticles was studied. The resultant hydrogels demonstrated a range of advantages, including good mechanical strength, porous morphology, amorphous structure, high swelling ratio, controlled biodegradability rate, and antibacterial activity. Additionally, a cytotoxicity analysis confirmed that the hydrogel scaffolds do not have adverse effects on the cells; our release studies in the hydrogel with the highest PVP content also showed 80% release after 30 days. Based on these results we were able to predict and control some of the mechanical properties, including the microstructure of the scaffolds, as well as the drug release, by optimizing the polymers - microparticle concentration, plus their resulting interactions. This optimized hydrogel can become part of a suitable alternative for treatment of allergic rhinitis and chronic sinusitis.

Aberrant MicroRNAomics in Pulmonary Complications: Implications in Lung Health and Diseases

Over the last few decades, evolutionarily conserved molecular networks have emerged as important regulators in the expression and function of eukaryotic genomes. Recently, miRNAs (miRNAs), a large family of small, non-coding regulatory RNAs were identified in these networks as regulators of endogenous genes by exerting post-transcriptional gene regulation activity in a broad range of eukaryotic species. Dysregulation of miRNA expression correlates with aberrant gene expression and can play an essential role in human health and disease. In the context of the lung, miRNAs have been implicated in organogenesis programming, such as proliferation, differentiation, and morphogenesis. Gain- or loss-of-function studies revealed their pivotal roles as regulators of disease development, potential therapeutic candidates/targets, and clinical biomarkers. An altered microRNAome has been attributed to several pulmonary diseases, such as asthma, chronic pulmonary obstructive disease, cystic fibrosis, lung cancer, and idiopathic pulmonary fibrosis. Considering the relevant roles and functions of miRNAs under physiological and pathological conditions, they may lead to the invention of new diagnostic and therapeutic tools. This review will focus on recent advances in understanding the role of miRNAs in lung development, lung health, and diseases, while also exploring the progress and prospects of their application as therapeutic leads or as biomarkers.