Ternary nanoparticles composed of cationic solid lipid nanoparticles, protamine, and DNA for gene delivery

Lipid nanoparticle: advanced drug delivery systems for promotion of angiogenesis in diabetic wounds

Diabetic wound is one of the most challenge in healthcare, requiring innovative approaches to promote efficient healing. In recent years, lipid nanoparticle-based drug delivery systems have emerged as a promising strategy for enhancing diabetic wound repair by stimulating angiogenesis. These nanoparticles offer unique advantages, including improved drug stability, targeted delivery, and controlled release, making them promising in enhancing the formation of new blood vessels. In this review, we summarize the emerging advances in the utilization of lipid nanoparticles to deliver angiogenic agents and promote angiogenesis in diabetic wounds. Furthermore, we provide an in-depth exploration of key aspects, including the intricate design and fabrication of lipid nanoparticles, their underlying mechanisms of action, and a comprehensive overview of preclinical studies. Moreover, we address crucial considerations pertaining to safety and the translation of these innovative systems into clinical practice. By synthesizing and analyzing the available knowledge, our review offers valuable insights into the future prospects and challenges associated with utilizing the potential of lipid nanoparticle-based drug delivery systems for promoting robust angiogenesis in the intricate process of diabetic wound healing.

Development of lipid nanoparticles and liposomes reference materials (II): cytotoxic profiles

Lipid based nanocarriers are one of the most effective drug delivery systems that is evident from the recent COVID-19 mRNA vaccines. The main objective of this study was to evaluate toxicity of six lipid based formulations with three surface charges-anionic, neutral or cationic, to establish certified reference materials (CRMs) for liposomes and siRNA loaded lipid nanoparticles (LNP-siRNA). Cytotoxicity was assessed by a proliferation assay in adherent and non-adherent cell lines. High concentration of three LNP-siRNAs did not affect viability of suspension cells and LNP-siRNAs were non-toxic to adherent cells at conventionally used concentration. Systematic evaluation using multiple vials and repeated test runs of three liposomes and three LNP-siRNA formulations showed no toxicity in HL60 and A549 cells up to 128 and 16 µg/mL, respectively. Extended treatment and low concentration of LNPs did not affect the viability of suspension cells and adherent cells at 96 h. Interestingly, 80% of A549 and HL60 cells in 3D conditions were viable when treated with cationic LNP-siRNA for 48 h. Taken together, anionic, cationic and neutral lipid formulations were non-toxic to cells and may be explored further in order to develop them as drug carriers.

Protamine-Lipid-dsRNA Nanoparticles Improve RNAi Efficiency in the Fall Armyworm, Spodoptera frugiperda

Developing safe and effective double-stranded RNA (dsRNA) delivery systems remains a major challenge for gene silencing, especially in lepidopteran insects. This study evaluated the protamine sulfate (PS)/lipid/dsRNA nanoparticle (NP) delivery system for RNA interference (RNAi) in cells and larvae of the fall armyworm (FAW), Spodoptera frugiperda, a major worldwide pest. A highly efficient gene delivery formulation was prepared using a cationic biopolymer, PS, and a cationic lipid, Cellfectin (CF), complexed with dsRNA. The NPs were prepared by a two-step self-assembly method. The formation of NPs was revealed by dynamic light scattering and transmission electron microscopy. The formation of CF/dsRNA/PS NPs was spherical in shape and size, ranging from 20 to 100 nm with a positive charge (+23.3 mV). Interestingly, prepared CF/dsRNA/PS NPs could protect dsRNA (95%) from nuclease degradation and thus significantly improve the stability of dsRNA. Formulations prepared by combining EGFP DNA with CF/PS increased transfection efficiency in Sf9 cells compared to PS/EGFP and CF/EGFP NPs. Also, the PS/CF/dsRNA NPs enhanced the endosomal escape for the intracellular delivery of dsRNA. The gene knockdown efficiency was assessed in Sf9 Luciferase (Luc) stable cells after a 72 h incubation with CF/dsRNA/PS, PS/dsRNA, CF/dsRNA, or naked dsRNA. Knockdown of the Luc gene was detected in CF/dsRNA/PS (76%) and PS/dsRNA (42.4%) not CF/dsRNA (19.5%) and naked dsRNA (10.3%) in Sf9 Luc cells. Moreover, CF/dsIAP/PS (25 μg of dsRNA targeting the inhibitor of apoptosis, IAP, gene of FAW) NPs showed knockdown of the IAP gene (39.5%) and mortality (55%) in FAW larvae. These results highlight the potential application of PS/lipid/dsRNA NPs for RNA-mediated control of insect pests.

Use of Protamine in Nanopharmaceuticals-A Review

Macromolecular biomolecules are currently dethroning classical small molecule therapeutics because of their improved targeting and delivery properties. Protamine-a small polycationic peptide-represents a promising candidate. In nature, it binds and protects DNA against degradation during spermatogenesis due to electrostatic interactions between the negatively charged DNA-phosphate backbone and the positively charged protamine. Researchers are mimicking this technique to develop innovative nanopharmaceutical drug delivery systems, incorporating protamine as a carrier for biologically active components such as DNA or RNA. The first part of this review highlights ongoing investigations in the field of protamine-associated nanotechnology, discussing the self-assembling manufacturing process and nanoparticle engineering. Immune-modulating properties of protamine are those that lead to the second key part, which is protamine in novel vaccine technologies. Protamine-based RNA delivery systems in vaccines (some belong to the new class of mRNA-vaccines) against infectious disease and their use in cancer treatment are reviewed, and we provide an update on the current state of latest developments with protamine as pharmaceutical excipient for vaccines.

PEGylated Protamine-Based Adsorbing Improves the Biological Properties and Stability of Tetrahedral Framework Nucleic Acids

Recently, many researchers have reported that DNA nanostructures, such as tetrahedral framework nucleic acids (tFNAs), have great potential to be useful tools in clinical and laboratory applications due to their programmable shapes, functional sites, and biological responses. However, finite endocytosis and stability in cells and body fluids compromise the functions of DNA nanostructures as a result of various adverse factors. In this study, we successfully synthesized PEGylated protamine, and tFNAs were adsorbed to it in a proper ratio of nitrogen in protamine to phosphorus in tFNAs (N/P ratio) as the functional complex. Furthermore, we demonstrated that PEGylated protamine-adsorbed tFNAs show a more prominent positive effect on cell viability and proliferation than naked tFNAs do. An increase in endocytosis can be observed in three different tissue-derived cells with the PEG-protamine-tFNA (PPT) complex. The increased endocytic ability is mediated by multiple pathways; moreover, the stimulatory effect of the PPT complex on the endocytic ability is dramatically blocked by the inhibition of the caveola-dependent pathway. Consistently, when tFNAs are stabilized by PEGylated protamine, they often tend to escape from lysosomes and survive for a longer period in biological fluids rather than being rapidly eliminated from the kidneys. The in vitro and in vivo results of our study demonstrate that the PPT complex method is a feasible, potent, and low-cost strategy that improves tFNA biocompatibility, stability, and internalization. This study provides evidence supporting the possibility of implementing PPTs for use in drug delivery, bioimaging, and gene transfection in the future.

Cascaded Aptamers-Governed Multistage Drug-Delivery System Based on Biodegradable Envelope-Type Nanovehicle for Targeted Therapy of HER2-Overexpressing Breast Cancer

Tumor-specific therapeutic platforms with improved targeting efficacy and minimized side effect are crucial in cancer therapy. Capitalizing on the recognition capability and biocompatibility of aptamers, we herein designed a multistage targeted drug-delivery system using multiple biodegradable molecules-enveloped nanovehicle that can be employed to efficiently treat human epithelial growth factor receptor (HER2)-overexpressing breast cancer. In this nanovehicle, two aptamers respectively specific to HER2 and ATP were organized in a hierarchical manner. The outmost HER2 aptamer (HB5) governs the recognition to HER2 protein overexpressed in SK-BR-3 cell lines, while the ATP aptamer incorporated with anticancer drug (-)-epigallocatechin gallate (EGCG) and protamine sulfate in the inner core functions as a switch of drug release in response to abundant intracellular ATP. The targeting and drug locker aptamers were cascaded for active targeting effect and stimuli responsiveness, guaranteeing the site-specific drug transportation and endogenous species-triggered drug release inside the tumor cells. Moreover, nanostructured lipid carriers (NLCs) were constructed to wrap and stabilize the loosely bounded ternary complex, minimizing premature drug leakage potentially encountered by the biomolecule assembled nanocarriers. This multiple biomolecules-enveloped nanovehicle demonstrated improved inhibitory actions on tumor growth and minimum side effect to normal organs and tissues both in vitro and in vivo. The presented nanovehicle built from recognition and therapeutic components in a nontoxic framework offered a promising drug-delivery platform with transport precision and biological safety.

Effect of A-317491 delivered by glycolipid-like polymer micelles on endometriosis pain

Endometriosis is a common gynecological disease with a lack of effective clinical treatment. Current therapy often results in endometriosis pain recurrence and serious side effects. P2X₃ receptor, an adenosine triphosphate (ATP)-gated ion channel, might be implicated in endometriosis pain. In this study, chitosan oligosaccharide-g-stearic acid (CSOSA) polymer micelles-coated nanostructured lipid carriers (NLCs) were developed as a novel delivery system for A-317491, a selective P2X₃ receptor antagonist for endometriosis pain therapy. A-317491-loaded NLC (NLC/A-317491) could be coated by CSOSA micelles to form CSOSA/NLC/A-317491 nanoparticles. Pheochromocytoma PC12 cells, which highly expressed P2X₃ receptors, were used as a cell model, and the CSOSA/NLC/A-317491 partly blocked the Ca²⁺ influx induced by ATP stimulation. In nude mouse and rat endometriotic models, CSOSA/NLC could accumulate into endometriotic lesions after vein injection. In endometriotic rats, CSOSA/NLC/A-317491 reversed mechanical and heat hyperalgesia with long-term efficacy, which might be attributed to the massive CSOSA/NLC/A-317491 distribution in the endometriotic lesions. In conclusion, A-317491 delivered by CSOSA/NLC nanoparticles attenuated endometriosis pain in rats, and CSOSA/NLC/A-317491 could be used as an effective treatment strategy for P2X₃-targeted therapy in endometriosis pain.

Trigger-Responsive Gene Transporters for Anticancer Therapy

In the current era of gene delivery, trigger-responsive nanoparticles for the delivery of exogenous nucleic acids, such as plasmid DNA (pDNA), mRNA, siRNAs, and miRNAs, to cancer cells have attracted considerable interest. The cationic gene transporters commonly used are typically in the form of polyplexes, lipoplexes or mixtures of both, and their gene transfer efficiency in cancer cells depends on several factors, such as cell binding, intracellular trafficking, buffering capacity for endosomal escape, DNA unpacking, nuclear transportation, cell viability, and DNA protection against nucleases. Some of these factors influence other factors adversely, and therefore, it is of critical importance that these factors are balanced. Recently, with the advancements in contemporary tools and techniques, trigger-responsive nanoparticles with the potential to overcome their intrinsic drawbacks have been developed. This review summarizes the mechanisms and limitations of cationic gene transporters. In addition, it covers various triggers, such as light, enzymes, magnetic fields, and ultrasound (US), used to enhance the gene transfer efficiency of trigger-responsive gene transporters in cancer cells. Furthermore, the challenges associated with and future directions in developing trigger-responsive gene transporters for anticancer therapy are discussed briefly.

MicroRNA-200c delivered by solid lipid nanoparticles enhances the effect of paclitaxel on breast cancer stem cell

Background

One of the major obstacles in the treatment of breast cancer is breast cancer stem cells (BCSC) which are resistant to standard chemotherapeutic drugs. It has been proven that microRNA-200c (miR-200c) can restore sensitivity to microtubule-targeting chemotherapeutic drugs by reducing the expression of class III β-tubulin. In this study, combination therapy with miR-200c and paclitaxel (PTX) mediated by lipid nanoparticles was investigated as an alternative strategy against BCSC.

Materials and methods

A cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane was strategically selected to formulate solid lipid nanoparticles (SLN) for miR-200c delivery. Nanostructured lipid carriers (NLC) with 20 wt% oleic acid were prepared for PTX delivery. Mammospheres, which gained the characteristics of BCSC, were used as a cell model to evaluate the efficiency of combination therapy.

Results

The cationic SLN could condense anionic miRNA to form SLN/miRNA complexes via charge interactions and could protect miRNA from degradation by ribonuclease. SLN/miR-200c complexes achieved 11.6-fold expression of miR-200c after incubation for 24 hours, compared with that of Lipofectamine™ 2000/miR-200c complexes (*P<0.05). Intracellular drug release assay proved that miRNA can be released from SLN/miRNA complexes efficiently in 12 hours after cellular uptake. After BCSC were transfected with SLN/miR-200c, the expression of class III β-tubulin was effectively downregulated and the cellular cytotoxicity of PTX-loaded NLC (NLC/PTX) against BCSC was enhanced significantly (**P<0.01).

Conclusion

The results indicated that the cationic SLN could serve as a promising carrier for miRNA delivery. In addition, the combination therapy of miR-200c and PTX revealed a novel therapeutic strategy for the treatment of BCSC.

Nanoparticle-based targeted gene therapy for lung cancer

Despite striking insights on lung cancer progression, and cutting-edge therapeutic approaches the survival of patients with lung cancer, remains poor. In recent years, targeted gene therapy with nanoparticles is one of the most rapidly evolving and extensive areas of research for lung cancer. The major goal of targeted gene therapy is to bring forward a safe and efficient treatment to cancer patients via specifically targeting and deterring cancer cells in the body. To achieve high therapeutic efficacy of gene delivery, various carriers have been engineered and developed to provide protection to the genetic materials and efficient delivery to targeted cancer cells. Nanoparticles play an important role in the area of drug delivery and have been widely applied in cancer treatments for the purposes of controlled release and cancer cell targeting. Nanoparticles composed of artificial polymers, proteins, polysaccharides and lipids have been developed for the delivery of therapeutic deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) sequences to target cancer. In addition, the effectiveness of cancer targeting has been enhanced by surface modification or conjugation with biomolecules on the surface of nanoparticles. In this review article we provide an overview on the latest developments in nanoparticle-based targeted gene therapy for lung cancers. Firstly, we outline the conventional therapies and discuss strategies for targeted gene therapy using nanoparticles. Secondly, we provide the most representative and recent researches in lung cancers including malignant pleural mesothelioma, mainly focusing on the application of Polymeric, Lipid-based, and Metal-based nanoparticles. Finally, we discuss current achievements and future challenges.

Nanoparticle-based technologies for retinal gene therapy

For patients with hereditary retinal diseases, retinal gene therapy offers significant promise for the prevention of retinal degeneration. While adeno-associated virus (AAV)-based systems remain the most popular gene delivery method due to their high efficiency and successful clinical results, other delivery systems, such as non-viral nanoparticles (NPs) are being developed as additional therapeutic options. NP technologies come in several categories (e.g., polymer, liposomes, peptide compacted DNA), several of which have been tested in mouse models of retinal disease. Here, we discuss the key biochemical features of the different NPs that influence how they are internalized into cells, escape from endosomes, and are delivered into the nucleus. We review the primary mechanism of NP uptake by retinal cells and highlight various NPs that have been successfully used for in vivo gene delivery to the retina and RPE. Finally, we consider the various strategies that can be implemented in the plasmid DNA to generate persistent, high levels of gene expression.