Preparation of Curdlan sulphate - Chitosan nanoparticles as a drug carrier to target Mycobacterium smegmatis infected macrophages

β-1,3 Glucan Microparticles & Nanoparticles: Fabrication Methods & Applications in Immunomodulation & Targeted Drug Delivery

Innate immune cells such as macrophages and dendritic cells play major roles in the progression of many cancerous, fibrotic, and autoimmune diseases, often due to environmental cues that skew these cells toward a phenotype that progresses or exacerbates the disease state. As such, a growing focus in treating such diseases is placed on exploiting the high plasticity of these cells to modify or reverse their pro-disease phenotypes using immunomodulatory materials. β-1,3 glucans are one such type of material that has exhibited diverse immunomodulatory effects on immune cells, including the mitigation or reversal of the adverse effects of dysregulated immune cells. In this review, we outline various fabrication techniques to produce β-1,3 glucan-derived microparticles and nanoparticles and discuss the diverse particle properties that can be obtained by tuning glucan chemistry, fabrication method, and formulation components. Furthermore, the immunomodulatory applications of β-1,3 glucan particles are highlighted with a focus on immune cell targeting, modulation, and the delivery of small molecule and macromolecular therapeutics.

A review on biomacromolecular ligand-directed nanoparticles: New era in macrophage targeting

Traditional drug delivery strategies often have side effects due to uneven drug distribution leading to the subtherapeutic impacts. Ligand-modified nanoparticles offer a revolutionary approach to precise drug delivery. These modified nanoparticles can potentially target macrophages, which is crucial for defense and disease progression efficiently. Out of many classes of ligands, biomacromolecular ligands emerged as potential ligands for directing these nanoparticles to macrophages due to their consecutive receptors over the macrophage surface, assisting easy internalization and thus supporting elevated efficacy and reduced toxicity. This approach could significantly improve treatment for diseases like cancer, tuberculosis, etc. by directing drugs to macrophages and reducing side effects. By leveraging nanotechnology and biomacromolecular-based ligand-directed targeting, we can achieve more precise and effective treatments, paving the way for advancements in precision medicine.

Chitosan and Its Derivatives as Nanocarriers for Drug Delivery

Chitosan (CS) occurs naturally as an alkaline polysaccharide and has been demonstrated to have several activities of a biological nature. Additionally, as CS chains have functional hydroxyl and amino groups that are active, their applications can be expanded by chemically or molecularly altering the molecules to incorporate new functional groups. Due to its outstanding qualities, including biodegradability, biocompatibility, non-toxicity, and accessibility, it has received significant interest in all areas of biomedicine and nanomaterials being extremely promising as drug nanocarrier. The last decades have produced a lot of interest in CS-based nanoparticles (CSNPs), with an increasing number of research papers from around 1500 in 2015 to almost 5000 in 2024. The degree of crosslinking, the particulate system's shape, size, and density, in addition to the drug's physical and chemical properties, all have a role in how the drug is transported and released from CSNPs. When creating potential drug delivery systems based on CSNPs, all these factors must be considered. In earlier, CSNPs were employed to enhance the pharmacotherapeutics, pharmacokinetics, and solubility properties of drugs. By investigating its positively charged characteristics and changeable functional groups, CS has evolved into a versatile drug delivery system. The drug release from CSNPs will definitely be influenced by various changes to the functional groups, charges, and polymer backbone. This review mainly discusses the most important results published in the last decade. Despite the promising advantages of CSNPs, challenges related to the translation into clinical stages remain and further in vitro and in vivo studies are mandatory.

Preparation and characterization of curdlan-chitosan conjugate nanoparticles as mucosal adjuvants for intranasal influenza H1N1 subunit vaccine

Intranasal vaccination offers crucial protection against influenza virus pandemics. However, antigens, especially subunit antigens, often fail to induce effective immune responses without the help of immune adjuvants. Our research has demonstrated that a polyelectrolyte complex, composed of curdlan sulfate/O-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (CS/O-HTCC), effectively triggers both mucosal and systemic immune responses when administrated intranasal. In this study, stable nanoparticles formed by curdlan-O-HTCC conjugate (CO NP) were prepared and characterized. Furthermore, the efficacy of CO NP was evaluated as a mucosal adjuvant in an intranasal influenza H1N1 subunit vaccine. The results revealed that CO NP exhibits uniform and spherical morphology, with a size of 190.53 ± 4.22 nm, and notably, it remains stable in PBS at 4 °C for up to 6 weeks. Biological evaluation demonstrated that CO NP stimulates the activation of antigen-presenting cells (APCs), including macrophages and dendritic cells (DCs), both in vitro and in vivo. Furthermore, intranasal administration of CO NP effectively elicits cellular and humoral immune responses, notably enhancing mucosal immunity. Thus, CO NP emerges as a promising mucosal adjuvant for influenza subunit vaccines.

Recent innovations (2020-2023) in the approaches for the chemical functionalization of curdlan and pullulan: A mini-review

Chemical modification represents a highly efficacious approach for enhancing the physicochemical characteristics and biological functionalities of natural polysaccharides. However, not all polysaccharides have considerable pharmacologic activity; so, appropriate chemical modification strategies can be selected in accordance with the distinct structural properties of polysaccharides to aid in improving and encouraging the presentation of their biological activities. Hence, there has been a growing interest in the chemical alteration of polysaccharides due to their various properties such as antioxidant, anticoagulant, antiviral, anticancer, biomedical, antibacterial, and immunomodulatory effects. This paper offers a comprehensive examination of recent scientific advancements produced over the past four years in the realm of unique chemical and functional modifications in curdlan and pullulan structures. This review aims to provide readers with an overview of the structural activity correlations observed in the backbone structures of curdlan and pullulan, as well as the diverse chemical modification processes employed for these polysaccharides. Additionally, the review aims to examine the effects of combining various bioactive molecules with chemically modified curdlan and pullulan and explore their potential applications in various important fields.

Multi-functional pH-responsive and biomimetic chitosan-based nanoplexes for targeted delivery of ciprofloxacin against bacterial sepsis

Bacterial sepsis is a mortal syndromic disease characterized by a complex pathophysiology that hinders effective targeted therapy. This study aimed to develop multifunctional, biomimetic and pH-responsive ciprofloxacin-loaded chitosan (CS)/sodium deoxycholic acid (SDC) nanoplexes (CS/SDC) nanoplexes with the ability to target and modulate the TLR4 pathway, activated during sepsis. The formulated nanoplexes were characterized in terms of physicochemical properties, in silico and in vitro potential biological activities. The optimal formulation showed good biocompatibility and stability with appropriate physicochemical parameters. The surface charge changed from negative at pH 7.4 to positive at pH 6.0 accompanied with a significantly faster release of CIP at pH 6.0 compared to 7.4. The biomimicry was elucidated by in silico tools and MST and results confirmed strong binding between the system and TLR4. Furthermore, the system revealed 4- and 2-fold antibacterial enhancement at acidic pH, and 3- and 4-fold better antibiofilm efficacy against Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (P. aeruginosa) respectively, compared to bare CIP. In addition, enhanced bacterial efflux pump inhibition was demonstrated by CS/SDC nanoplexes. Finally, the developed nanosystem showed excellent antioxidant activity against DPPH radicals. Taken together, the study confirmed the multi-functionalities of CS/SDC nanoplexes and their potential benefits in improving bacterial sepsis therapy.

Naturally and Chemically Sulfated Polysaccharides in Drug Delivery Systems

Sulfated polysaccharides have always attracted much attention in food, cosmetic and pharmaceutical industries. These polysaccharides can be obtained from natural sources such as seaweeds (agarans, carrageenans, fucoidans, mannans and ulvans), or animal tissues (glucosaminoglycans). In the last few years, several neutral or cationic polysaccharides have been sulfated by chemical methods and anionic or amphoteric derivatives were obtained, respectively, for drug delivery and other biomedical applications. An important characteristic of sulfated polysaccharides in this field is that they can associate with cationic drugs generating polyelectrolyte-drug complexes, or with cationic polymers to form interpolyelectrolyte complexes, with hydrogel properties that expand even more their applications. The aims of this chapter are to present the structural characteristics of these polysaccharides, to describe the methods of sulfation applied and to review extensively and discuss developments in their use or their role in interpolyelectrolyte complexes in drug delivery platforms. A variety of pharmaceutical dosage forms which were developed and administered by multiple routes (oral, transdermal, ophthalmic, and pulmonary, among others) to treat diverse pathologies were considered. Different IPECs were formed employing these sulfated polysaccharides as the anionic component. The most widely investigated is κ-carrageenan. Chitosan is usually employed as a cationic polyelectrolyte, with a variety of sulfated polysaccharides, besides the applications of chemically sulfated chitosan. Although chemical sulfation is often carried out in neutral polysaccharides and, to a less extent, in cationic ones, examples of oversulfation of naturally sulfated fucoidan have been found which improve its drug binding capacity and biological properties.

Fabrication and evaluation of agarose-curdlan blend derived multifunctional nanofibrous mats for diabetic wounds

Diabetic wounds with complex pathophysiology significantly burden the wound care industry and require novel management strategies. In the present study, we hypothesized that agarose-curdlan based nanofibrous dressings could be an effective biomaterial for addressing diabetic wounds due to their inherent healing properties. Hence, agarose/curdlan/polyvinyl alcohol based nanofibrous mats loaded with ciprofloxacin (0, 1, 3, and 5 wt%) were fabricated using an electrospinning technique with water and formic acid. In vitro evaluation revealed the average diameter of the fabricated nanofibers between 115 and 146 nm with high swelling (~450-500 %) properties. They exhibited enhanced mechanical strength (7.46 ± 0.80 MPa -7.79 ± 0.007 MPa) and significant biocompatibility (~90-98 %) with L929 and NIH 3T3 mouse fibroblasts. In vitro scratch assay showed higher proliferation and migration of fibroblasts (~90-100 % wound closure) compared to electrospun PVA and control. Significant antibacterial activity was observed against Escherichia coli and Staphylococcus aureus. In vitro real-time gene expression studies with human THP-1 cell line revealed a significant downregulation of pro-inflammatory cytokines (8.64 fold decrease for TNF-α) and upregulation of anti-inflammatory cytokines (6.83 fold increase for IL-10) compared to lipopolysaccharide. In brief, the results advocate agarose-curdlan mat as a potential multifunctional, bioactive, and eco-friendly dressing for healing diabetic wounds.

Gelatin and Chitosan as Meat By-Products and Their Recent Applications

Meat by-products such as bones, skin, horns, hooves, feet, skull, etc., are produced from slaughtered mammals. Innovative solutions are very important to achieving sustainability and obtaining the added value of meat by-products with the least impact on the environment. Gelatin, which is obtained from products high in collagen, such as dried skin and bones, is used in food processing, and pharmaceuticals. Chitosan is derived from chitin and is well recognized as an edible polymer. It is a natural product that is non-toxic and environmentally friendly. Recently, chitosan has attracted researchers' interests due to its biological activities, including antimicrobial, antitumor, and antioxidant properties. In this review, article, we highlighted the recent available information on the application of gelatin and chitosan as antioxidants, antimicrobials, food edible coating, enzyme immobilization, biologically active compound encapsulation, water treatment, and cancer diagnosis.

3D-Printed EVA Devices for Antiviral Delivery and Herpes Virus Control in Genital Infection

Herpes viruses are widespread in the human population and can cause many different diseases. Genital herpes is common and can increase the risk of HIV infection and neonatal herpes. Acyclovir is the most used drug for herpes treatment; however, it presents some disadvantages due to its poor oral bioavailability. In this study, some ethylene vinyl acetate devices with different acyclovir amounts (0, 10, and 20 wt.%) were manufactured by fused filament fabrication in two different geometries, an intrauterine device, and an intravaginal ring. Thermal analyses suggested that the crystallinity of EVA decreased up to 8% for the sample loaded with 20 wt.% of acyclovir. DSC, SEM, and FTIR analyses confirmed that the drug was successfully incorporated into the EVA matrix. Moreover, the drug release tests suggested a burst release during the first 24 h followed by a slower release rate sustained up to 80 days. Biological assays showed the biocompatibility of the EVA/ACV device, as well as a 99% reduction in vitro replication of HSV-1. Finally, the EVA presented a suitable performance for 3D printing manufacturing that can contribute to developing personalized solutions for long-term herpes treatment.

D-Pinitol-Active Natural Product from Carob with Notable Insulin Regulation

Carob is one of the major food trees for peoples of the Mediterranean basin, but it has also been traditionally used for medicinal purposes. Carob contains many nutrients and active natural products, and D-Pinitol is clearly one of the most important of these. D-Pinitol has been reported in dozens of scientific publications and its very diverse medicinal properties are still being studied. Presently, more than thirty medicinal activities of D-Pinitol have been reported. Among these, many publications have reported the strong activities of D-Pinitol as a natural antidiabetic and insulin regulator, but also as an active anti-Alzheimer, anticancer, antioxidant, and anti-inflammatory, and is also immune- and hepato-protective. In this review, we will present a brief introduction of the nutritional and medicinal importance of Carob, both traditionally and as found by modern research. In the introduction, we will present Carob’s major active natural products. The structures of inositols will be presented with a brief literature summary of their medicinal activities, with special attention to those inositols in Carob, as well as D-Pinitol’s chemical structure and its medicinal and other properties. D-Pinitol antidiabetic and insulin regulation activities will be extensively presented, including its proposed mechanism of action. Finally, a discussion followed by the conclusions and future vision will summarize this article.

Biosynthesis and applications of curdlan

Curdlan is widely applied in the food and pharmaceutical industries. This review focuses on the biosynthetic pathways, regulatory mechanisms and metabolic engineering strategies for curdlan production. Firstly, curdlan biosynthesis is discussed. Furthermore, various strategies to increase curdlan production are summarized from four aspects, including the overexpression of genes for curdlan biosynthesis, weakening/knockdown of genes from competing pathways, increasing the supply of curdlan precursors, and optimization of fermentation conditions. Moreover, the emerging and advanced applications of curdlan are introduced. Finally, the challenges that are frequently encountered during curdlan biosynthesis are noted with a discussion of directions for curdlan production.

Advances in Chitosan-Based Nanoparticles for Drug Delivery

Nanoparticles (NPs) have an outstanding position in pharmaceutical, biological, and medical disciplines. Polymeric NPs based on chitosan (CS) can act as excellent drug carriers because of some intrinsic beneficial properties including biocompatibility, biodegradability, non-toxicity, bioactivity, easy preparation, and targeting specificity. Drug transport and release from CS-based particulate systems depend on the extent of cross-linking, morphology, size, and density of the particulate system, as well as physicochemical properties of the drug. All these aspects have to be considered when developing new CS-based NPs as potential drug delivery systems. This comprehensive review is summarizing and discussing recent advances in CS-based NPs being developed and examined for drug delivery. From this point of view, an enhancement of CS properties by its modification is presented. An enhancement in drug delivery by CS NPs is discussed in detail focusing on (i) a brief summarization of basic characteristics of CS NPs, (ii) a categorization of preparation procedures used for CS NPs involving also recent improvements in production schemes of conventional as well as novel CS NPs, (iii) a categorization and evaluation of CS-based-nanocomposites involving their production schemes with organic polymers and inorganic material, and (iv) very recent implementations of CS NPs and nanocomposites in drug delivery.

Synthesis and Biological Evaluation of a Novel Glycidyl Metharcylate/Phaytic Acid-Based on Bagasse Xylan Composite Derivative

The development of natural biomass materials with excellent properties is an attractive way to improve the application range of natural polysaccharides. Bagasse Xylan (BX) is a natural polysaccharide with various biological activities, such as antitumor, antioxidant, etc. Its physic-chemical and biological properties can be improved by functionalization. For this purpose, a novel glycidyl metharcylate/phytic acid based on a BX composite derivative was synthesized by a free radical polymerization technique with glycidyl metharcylate (GMA; GMABX) and further esterification with phytic acid (PA; GMABX-PA) in ionic liquid. The effects of the reaction conditions (i.e., temperature, time, initiator concentration, catalyst concentration, GMA concentration, PA concentration, mass of ionic liquid) on grafting rate(G), conversion rate(C) and degree of substitution(DS) are discussed. The structure of the composite material structure was confirmed by FTIR, 1H NMR and XRD. SEM confirmed the particle morphology of the composite derivative. The thermal stability of GMABX-PA was determined by TG-DTG. Molecular docking was further performed to study the combination mode of the GMABX-PA into the active site of two lung cancer proteins (5XNV, 2EB2) and a blood cancer protein (2M6N). In addition, tumor cell proliferation inhibition assays for BX, GMABX-PA were carried out using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetraz -olium bromide (MTT) method. The results showed that various reaction conditions exhibited favorable gradient curves, and that a maximum G of 56% for the graft copolymerization and a maximum DS of 0.267 can be achieved. The thermal stability was significantly improved, as demonstrated by the fact that there was still 60% residual at 800 °C. The molecular docking software generated satisfactory results with regard to the evaluated binding energy and combining sites. The inhibition ratio of GMABX-PA on NCI-H460 (lung cancer cells) reached 29.68% ± 4.45%, which is five times higher than that of BX. Therefore, the material was shown to be a potential candidate for biomedical applications as well as for use as a heat resistant material.