Inulin Derivatives Obtained Via Enhanced Microwave Synthesis for Nucleic Acid Based Drug Delivery

The landscape of nanoparticle-based siRNA delivery and therapeutic development

Five small interfering RNA (siRNA)-based therapeutics have been approved by the Food and Drug Administration (FDA), namely patisiran, givosiran, lumasiran, inclisiran, and vutrisiran. Besides, siRNA delivery to the target site without toxicity is a big challenge for researchers, and naked-siRNA delivery possesses several challenges, including membrane impermeability, enzymatic degradation, mononuclear phagocyte system (MPS) entrapment, fast renal excretion, endosomal escape, and off-target effects. The siRNA therapeutics can silence any disease-specific gene, but their intracellular and extracellular barriers limit their clinical applications. For this purpose, several modifications have been employed to siRNA for better transfection efficiency. Still, there is a quest for better delivery systems for siRNA delivery to the target site. In recent years, nanoparticles have shown promising results in siRNA delivery with minimum toxicity and off-target effects. Patisiran is a lipid nanoparticle (LNP)-based siRNA formulation for treating hereditary transthyretin-mediated amyloidosis that ultimately warrants the use of nanoparticles from different classes, especially lipid-based nanoparticles. These nanoparticles may belong to different categories, including lipid-based, polymer-based, and inorganic nanoparticles. This review briefly discusses the lipid, polymer, and inorganic nanoparticles and their sub-types for siRNA delivery. Finally, several clinical trials related to siRNA therapeutics are addressed, followed by the future prospects and conclusions.

Application of plant products in the synthesis and functionalisation of biopolymers

The burning of plastic trash contributes significantly to the problem of air pollution. Consequently, a wide variety of toxic gases get released into the atmosphere. It is of the utmost importance to develop biodegradable polymers that retain the same characteristics as those obtained from petroleum. In order to decrease the effect that these issues have on the world around us, we need to focus our attention on specific alternative sources capable of biodegrading in their natural environments. Biodegradable polymers have garnered much attention since they can break down through the processes carried out by living creatures. Biopolymers' applications are growing due to their non-toxic nature, biodegradability, biocompatibility, and environmental friendliness. In this regard, we examined numerous methods used to manufacture biopolymers and the critical components from which they get their functional properties. In recent years, economic and environmental concerns have reached a tipping point, increasing production based on sustainable biomaterials. This paper examines plant-based biopolymers as a good resource with potential applications in both biological and non-biological sectors. Scientists have devised various biopolymer synthesis and functionalization techniques to maximize its utility in various applications. In conclusion, recent developments in the functionalization of biopolymers through various plant products and their applications are discussed.

Inulin as a multifaceted (active) substance and its chemical functionalization: From plant extraction to applications in pharmacy, cosmetics and food

This review is aimed at critically discussing a collection of research papers on Inulin (INU) in different scientific fields. The first part of this work gives an overview on the main characteristics of native INU, including production, applications in food or cosmetics industries, its benefits on human health as well as its main nutraceutical properties. A particular focus is dedicated to the extraction techniques and to the specific effects of INU on intestinal microbiota. Other than in food industry, the number of INU applications increases dramatically in the pharmaceutical field especially due to its simple chemical functionalization. Thus, aim of this review is also to give practical examples of chemical functionalization performed on INU also by including critical comments based on the direct experience of the Authors. With this aim, a full paragraph is dedicated to practical chemical experiences useful to reduce the efforts when establishing new experimental conditions. Moreover, the pharmaceutical technology is also taken in special consideration by underlining the aspects leading at the preparation of formulations based on INU. At the end of the review, a critical paragraph is intended to feed the scientists' curiosity on this versatile polysaccharide.

Combining Inulin Multifunctional Polycation and Magnetic Nanoparticles: Redox-Responsive siRNA-Loaded Systems for Magnetofection

Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are recognized as one of the most promising agents for theranostic applications. Among methods designed for siRNA delivery, magnetofection, that is, nucleic acid cell uptake under the influence of a magnetic field acting on magnetic nucleic acid vectors, is emerging as a unique approach to combining advantages such as strong improvement of the kinetics of the delivery process and the possibility of localizing nucleic acid delivery to an area where the magnetic field is applied. This paper reports on the preparation of siRNA loaded magnetoplexes—named ICD@SS@SPIONs/siRNA—by controlled crosslinking, in the presence of SPIONs, of the polycation INU-C-DETA, synthesized starting from the polysaccharide inulin by grafting diethylenetriamine and cystamine molecules. The obtained ICD@SS@SPIONs/siRNA have suitable chemical-physical characteristics to be employed for iv administration and are also able to release siRNA in a redox-triggered manner thanks to intracellular glutathione (GSH) mediated reduction of disulphide bridges formed during the crosslinking process. Moreover, ICD@SS@SPIONs/siRNA are able to produce magnetic targeting in vitro on breast cancer cells, without appreciable cyto- and hemo-toxic effects, in a wide range of concentrations. Finally, protein binding to nanoparticles revealed that obtained systems are potentially longer circulating and applicable as a smart multifunctional agents for cancer therapy.

Inulin-Ethylenediamine Coated SPIONs Magnetoplexes: A Promising Tool for Improving siRNA Delivery

PURPOSE

An inulin based polycation (Inu-EDA) has been synthesized by the grafting of ethylenediamine molecules onto inulin backbone. The obtained inulin copolymer has been though to coat SPIONs (IC-SPIONs) and obtain stable magnetoplexes by complexation of IC-SPIONs with a model duplexed siRNA, for improving oligonucleotide transfection efficiency.

METHODS

The physical-chemical characteristics of IC-SPIONs and IC-SPIONs/siRNA magnetoplexes have been investigated by scanning and transmission electron microscopies, dynamic light scattering, FT-IR and qualitative surface elementary analysis. Cell compatibility and internalization in vitro of IC-SPIONs have been evaluated by MTS and fluorescence microscopy respectively on cancer (HCT116) and normal human (16HBE) cells. The efficiency of gene silencing effect of magnetoplexes was studied on both tumoral (JHH6) and non tumoral (16HBE) cell lines also by applying an external magnet.

RESULTS

IC-SPIONs showed dimension of 30 nm and resulted cytocompatible on the tested cell lines; in the presence of an external magnet, the magnetic force enhanced the IC-SPIONs uptake inside cells. Magnetically improved transfection was observed in 16HBE cells under magnetofective conditions, in accordance with the IC-SPIONs uptake enhancement in the presence of an external magnet.

CONCLUSIONS

These findings support the potential application of this system as a magnetically targeted drug delivery system. Graphical Abstract Magnetically improved siRNA transfection in cells under magnetofective conditions upon uptake enhancement of IC-SPIONs in the presence of an external magnet.