Chitosan Based MicroRNA Nanocarriers

An injectable, nanostructured implant for the delivery of adenosine triphosphate: towards long-acting formulations of small, hydrophilic drugs

While long-acting injectable treatments are gaining increasing interest in managing chronic diseases, the available drug delivery systems almost exclusively rely on hydrophobic matrixes, limiting their application to either hydrophobic drugs or large and hydrophilic molecules such as peptides. To address the technological lock for long-acting delivery systems tailored to small, hydrophilic drugs such as anticancer and antiviral nucleoside/nucleotide analogues, we have synthesized and characterized an original approach with a multi-scale structure: (i) a nucleotide (adenosine triphosphate, ATP) is first incorporated in hydrophilic chitosan-Fe(III) nanogels; (ii) these nanogels are then transferred by freeze-drying and resuspension into a water-free, hydrophobic medium containing PLGA and an organic solvent, N-methyl-2-pyrrolidone. We show that this specific association allows an injectable and homogeneous dispersion, able to form in situ implants upon injection in physiological or aqueous environments. This system releases ATP in vitro without any burst effect in a two-step mechanism, first as nanogels acting as an intermediate reservoir over a week, then as free drug over several weeks. In vivo studies confirmed the potential of such nanostructured implants for sustained drug release following subcutaneous injection to mice hock, opening perspectives for sustained and targeted delivery through the lymphatic system.

Nanoassemblies of Chitosan-Based Polyelectrolyte Complexes as Nucleic Acid Delivery Systems

Nucleic acid delivery requires vectorization for protection from nucleases, preventing clearance by the reticuloendothelial system, and targeting to allow cellular uptake. Nanovectors meeting the above specifications should be safe for the patient, simple to manufacture, and display long-term stability. Our nanovectors were obtained via the green process of polyelectrolyte complexation, carried out at 25 °C in water at a low shear rate using chitosan (a polycationic biocompatible polysaccharide of specific molar mass and acetylation degree) and dextran sulfate as a polyanionic biocompatible polysaccharide. These complexes formed nanoassemblies of primary nanoparticles (20-35 nm) and maintained their colloidal stability for over 1 year at 25 °C. They could be steam sterilized, and a model nucleic acid could be either encapsulated or surface adsorbed. A targeting agent was finally bound to their surface. This work serves as a proof of concept of the suitability of chitosan-based polyelectrolyte complexes as nanovectors by sequential multilayered adsorption of various biomacromolecules.

Gene Therapy with Chitosan Nanoparticles: Modern Formulation Strategies for Enhancing Cancer Cell Transfection

Gene therapy involves the introduction of exogenous genetic material into host tissues to modify gene expression or cellular properties for therapeutic purposes. Initially developed to address genetic disorders, gene therapy has expanded to encompass a wide range of conditions, notably cancer. Effective delivery of nucleic acids into target cells relies on carriers, with non-viral systems gaining prominence due to their enhanced safety profile compared to viral vectors. Chitosan, a biopolymer, is frequently utilized to fabricate nanoparticles for various biomedical applications, particularly nucleic acid delivery, with recent emphasis on targeting cancer cells. Chitosan's positively charged amino groups enable the formation of stable nanocomplexes with nucleic acids and facilitate interaction with cell membranes, thereby promoting cellular uptake. Despite these advantages, chitosan-based nanoparticles face challenges such as poor solubility at physiological pH, non-specificity for cancer cells, and inefficient endosomal escape, limiting their transfection efficiency. To address these limitations, researchers have focused on enhancing the functionality of chitosan nanoparticles. Strategies include improving stability, enhancing targeting specificity, increasing cellular uptake efficiency, and promoting endosomal escape. This review critically evaluates recent formulation approaches within these categories, aiming to provide insights into advancing chitosan-based gene delivery systems for improved efficacy, particularly in cancer therapy.

Preparation and Optimization of MiR-375 Nano-Vector Using Two Novel Chitosan-Coated Nano-Structured Lipid Carriers as Gene Therapy for Hepatocellular Carcinoma

Currently, there is still a lack of effective carriers with minimal side effects to deliver therapeutic miRNA. Thus, it is crucial to optimize novel drug delivery systems. MiR-375 has proven superior therapeutic potency in Hepatocellular carcinoma (HCC). The purpose of this study was to fabricate 2 novel and smart nano-carriers for the transportation efficiency of miR-375 in HCC cells and enhance its anti-tumor effects. We established the miR-375 construct through the pEGP- miR expression vector. Two nano-carriers of solid/liquid lipids and chitosan (CS) were strategically selected, prepared by high-speed homogenization, and optimized by varying nano-formulation factors. Thus, the two best nano-formulations were designated as F1 (0.5% CS) and F2 (1.5% CS) and were evaluated for miR-375 conjugation efficiency by gel electrophoresis and nanodrop assessment. Then, physio-chemical characteristics and stability tests for the miR-375 nano-plexes were all studied. Next, its efficiencies as replacement therapy in HepG2 cells have been assessed by fluorescence microscopy, flow cytometry, and cytotoxicity assay. The obtained data showed that two cationic nanostructured solid/liquid lipid carriers (NSLCs); F1 and F2 typically had the best physio-chemical parameters and long-term stability. Moreover, both F1 and F2 could form nano-plexes with the anionic miR-375 construct at weight ratios 250/1 and 50/1 via electrostatic interactions. In addition, these nano-plexes exhibited physical stability after three months and protected miR-375 from degradation in the presence of 50% fetal bovine serum (FBS). Furthermore, both nano-plexes could simultaneously deliver miR-375 into HepG2 cells and they ensure miR re-expression even in the presence of 50% FBS compared to free miR-375 (p-value < 0.001). Moreover, both F1 and F2 alone significantly exhibited minimal cytotoxicity in treated cells. In contrast, the nano-plexes significantly inhibited cell growth compared to free miR-375 or doxorubicin (DOX), respectively. More importantly, F2/miR-375 nano-plex exhibited more anti-proliferative activity in treated cells although its IC50 value was 55 times lower than DOX (p-value < 0.001). Collectively, our findings clearly emphasized the multifunctionality of the two CS-coated NSLCs in terms of their enhanced biocompatibility, biostability, conjugation, and transfection efficiency of therapeutic miR-375. Therefore, the NSLCs/miR-375 nano-plexes could serve as a novel and promising therapeutic strategy for HCC.

Chitosan nanocarriers for non-coding RNA therapeutics: A review

Non-coding RNA (ncRNA)-based therapies entail delivering ncRNAs to cells to regulate gene expression and produce proteins that combat infections, cancer, neurological diseases, and bone abnormalities. Nevertheless, the therapeutic potential of these ncRNAs has been limited due to the difficulties in delivering them to specific cellular targets within the body. Chitosan (CS), a biocompatible cationic polymer, interacts with negatively charged RNA molecules to form stable complexes. It is a promising biomaterial to develop nanocarriers for ncRNA delivery, overcoming several disadvantages of traditional delivery systems. CS-based nanocarriers can protect ncRNAs from degradation and target-specific delivery by surface modifications and intracellular release profiles over an extended period. This review briefly summarizes the recent developments in CS nanocarriers' synthesis and design considerations and their applications in ncRNA therapeutics for treating various diseases. We also discuss the challenges and limitations of CS-based nanocarriers for ncRNA therapeutics and potential strategies for overcoming these challenges.

MicroRNA-targeting nanomedicines for the treatment of intervertebral disc degeneration

Low back pain stands as a pervasive global health concern, afflicting almost 80% of adults at some point in their lives with nearly 40% attributable to intervertebral disc degeneration (IVDD). As only symptomatic relief can be offered to patients there is a dire need for innovative treatments.Given the accumulating evidence that multiple microRNAs (miRs) are dysregulated during IVDD, they could have a huge potential against this debilitating condition. The way miRs can profoundly modulate signaling pathways and influence several cellular processes at once is particularly exciting to tackle this multifaceted disorder. However, miR delivery encounters extracellular and intracellular biological barriers. A promising technology to address this challenge is the vectorization of miRs within nanoparticles, providing both protection and enhancing their uptake within the scarce target cells of the degenerated IVD. This comprehensive review presents the diverse spectrum of miRs' connection with IVDD and demonstrates their therapeutic potential when vectorized in nanomedicines.

Role of long noncoding RNAs in pathological cardiac remodeling after myocardial infarction: An emerging insight into molecular mechanisms and therapeutic potential

Myocardial infarction (MI) is the leading cause of heart failure (HF), accounting for high mortality and morbidity worldwide. As a consequence of ischemia/reperfusion injury during MI, multiple cellular processes such as oxidative stress-induced damage, cardiomyocyte death, and inflammatory responses occur. In the next stage, the proliferation and activation of cardiac fibroblasts results in myocardial fibrosis and HF progression. Therefore, developing a novel therapeutic strategy is urgently warranted to restrict the progression of pathological cardiac remodeling. Recently, targeting long non-coding RNAs (lncRNAs) provided a novel insight into treating several disorders. In this regard, numerous investigations have indicated that several lncRNAs could participate in the pathogenesis of MI-induced cardiac remodeling, suggesting their potential therapeutic applications. In this review, we summarized lncRNAs displayed in the pathophysiology of cardiac remodeling after MI, emphasizing molecular mechanisms. Also, we highlighted the possible translational role of lncRNAs as therapeutic targets for this condition and discussed the potential role of exosomes in delivering the lncRNAs involved in post-MI cardiac remodeling.

Influence of GO-Antisense miRNA-21 on the Expression of Selected Cytokines at Glioblastoma Cell Lines

Introduction

Graphene oxide (GO) is a single layer of carbon atoms with unique properties, which are beneficial due to its surface functionalisation by miRNA. miRNAs are a non-coding small form of RNA that suppress the expression of protein-coding genes by translational repression or degradation of messenger RNA. Antisense miRNA-21 is very promising for future investigation in cancer therapy. This study aimed to detect cytokine expression levels after the administration of GO-antisense miRNA-21 into U87, U118, U251 and T98 glioma cell lines.

Methods

U87, U118, U251 and T98 glioma cell line were investigated in term of viability, human cytokine expression level at protein and genes after treatment with GO, GO-antisense miRNA-21 and antisense miRNA-21. The delivery of antisense miRNA-21 into the glioma cell at in vitro investigation were conducted by GO based transfection and electroporation.

Results

The results of the protein microarray and gene expression profile showed that complexes of GO-antisense miRNA-21 modified the metallopeptidase inhibitor 2 (TIMP-2), interleukin-6 (IL-6), interleukin 8 (IL-8), intercellular adhesion molecule 1 (ICAM-1), and monocyte chemoattractant protein-1 (MCP-1) expression level compared to transfection by electroporation of antisense miRNA-21 at investigated glioblastoma cell lines. The TIMP-2 protein and gene expression level was upregulated after antisense miRNA-21 delivery by GO complex into U87, U251 and T98 glioblastoma cell lines comparing to the non-treated control group. The downregulation at protein expression level of ICAM - 1 was observed at U87, U118, U251 and T98 glioma cell lines. Moreover, the IL-8 expression level at mRNA for genes and protein was decreased significantly after delivery the antisense-miRNA-21 by GO compared to electroporation as a transfection method.

Discussion

This work demonstrated that the graphene oxide complexes with antisense miRNA-21 can effectively modulate the cytokine mRNA and protein expression level at U87, U118, U251 and T98 glioma cell lines.

Chitosan-Based Nanoparticles for Nucleic Acid Delivery: Technological Aspects, Applications, and Future Perspectives

Chitosan is a naturally occurring polymer derived from the deacetylation of chitin, which is an abundant carbohydrate found mainly in the shells of various marine and terrestrial (micro)organisms. Chitosan has been extensively used to construct nanoparticles (NPs), which are biocompatible, biodegradable, non-toxic, easy to prepare, and can function as effective drug delivery systems. Moreover, chitosan NPs have been employed in gene and vaccine delivery, as well as advanced cancer therapy, and they can also serve as new therapeutic tools against viral infections. In this review, we summarize the most recent developments in the field of chitosan-based NPs intended as nucleic acid delivery vehicles and gene therapy vectors. Special attention is given to the technological aspects of chitosan complexes for nucleic acid delivery.

Quaternized chitosan (nano)fibers: A journey from preparation to high performance applications

The industrial production of chitosan, initiated over 50 years ago, has transformed its application across diverse industries, agriculture, and medicine. To enhance its properties, numerous chitosan derivatives have been synthesized. The quaternization of chitosan has proven beneficial, as it not only enhances its properties but also imparts water solubility, expanding its potential for a wider range of applications. Specifically, the utilization of quaternized chitosan-based nanofibers has leveraged the synergistic benefits of quaternized chitosan (including hydrophilicity, bioadhesiveness, antimicrobial, antioxidant, hemostatic, and antiviral activities, as well as ionic conductivity) in combination with the distinctive characteristics of nanofibers (such as a high aspect ratio and 3D architecture). This combination has permitted numerous possibilities, spanning from wound dressings, air and water filters, drug delivery scaffolds, antimicrobial textiles, to energy storage systems and alkaline fuel cells. In this comprehensive review, we examine the preparation methods, properties, and applications of various composite fibers containing quaternized chitosan. The advantages and disadvantages of each method and composition are meticulously summarized, while relevant diagrams and figures illustrate the key findings.

Chitosan-Based Nano-Smart Drug Delivery System in Breast Cancer Therapy

Despite recent advances, cancer remains the primary killer on a global scale. Numerous forms of research have been conducted to discover novel and efficient anticancer medications. The complexity of breast cancer is a major challenge which is coupled with patient-to-patient variations and heterogeneity between cells within the tumor. Revolutionary drug delivery is expected to provide a solution to that challenge. Chitosan nanoparticles (CSNPs) have prospects as a revolutionary delivery system capable of enhancing anticancer drug activity and reducing negative impacts on normal cells. The use of smart drug delivery systems (SDDs) as delivering materials to improve the bioactivity of NPs and to understand the intricacies of breast cancer has garnered significant interest. There are many reviews about CSNPs that present various points of view, but they have not yet described a series in cancer therapy from cell uptake to cell death. With this description, we will provide a more complete picture for designing preparations for SDDs. This review describes CSNPs as SDDSs, enhancing cancer therapy targeting and stimulus response using their anticancer mechanism. Multimodal chitosan SDDs as targeting and stimulus response medication delivery will improve therapeutic results.

Nanocarrier system: An emerging strategy for bioactive peptide delivery

Compared with small-molecule synthetic drugs, bioactive peptides have desirable advantages in efficiency, selectivity, safety, tolerance, and side effects, which are accepted by attracting extensive attention from researchers in food, medicine, and other fields. However, unacceptable barriers, including mucus barrier, digestive enzyme barrier, and epithelial barrier, cause the weakening or the loss of bioavailability and biostability of bioactive peptides. The nanocarrier system for bioactive peptide delivery needs to be further probed. We provide a comprehensive update on the application of versatile delivery systems for embedding bioactive peptides, including liposomes, polymer nanoparticles, polysaccharides, hydrogels, and self-emulsifying delivery systems, and further clarify their structural characterization, advantages, and disadvantages as delivery systems. It aims to provide a reference for the maximum utilization of bioactive peptides. It is expected to be an effective strategy for improving the bioavailability and biostability of bioactive peptides.