Polysaccharide-Based Biomaterials for Protein Delivery

Advances in the treatment of atherosclerosis with ligand-modified nanocarriers

Atherosclerosis, a chronic disease associated with metabolism, poses a significant risk to human well-being. Currently, existing treatments for atherosclerosis lack sufficient efficiency, while the utilization of surface-modified nanoparticles holds the potential to deliver highly effective therapeutic outcomes. These nanoparticles can target and bind to specific receptors that are abnormally over-expressed in atherosclerotic conditions. This paper reviews recent research (2018-present) advances in various ligand-modified nanoparticle systems targeting atherosclerosis by specifically targeting signature molecules in the hope of precise treatment at the molecular level and concludes with a discussion of the challenges and prospects in this field. The intention of this review is to inspire novel concepts for the design and advancement of targeted nanomedicines tailored specifically for the treatment of atherosclerosis.

Biomaterials for Protein Delivery: Opportunities and Challenges to Clinical Translation

The development of biomaterials for protein delivery is an emerging field that spans materials science, bioengineering, and medicine. In this review, we highlight the immense potential of protein-delivering biomaterials as therapeutic options and discuss the multifaceted challenges inherent to the field. We address current advancements and approaches in protein delivery that leverage stimuli-responsive materials, harness advanced fabrication techniques like 3D printing, and integrate nanotechnologies for greater targeting and improved stability, efficacy, and tolerability profiles. We also discuss the demand for highly complex delivery systems to maintain structural integrity and functionality of the protein payload. Finally, we discuss barriers to clinical translation, such as biocompatibility, immunogenicity, achieving reliable controlled release, efficient and targeted delivery, stability issues, scalability of production, and navigating the regulatory landscape for such materials. Overall, this review summarizes insights from a survey of the current literature and sheds light on the interplay between innovation and the practical implementation of biomaterials for protein delivery.

Biopolymer-Based Nanogel Approach in Drug Delivery: Basic Concept and Current Developments

Due to their increased surface area, extent of swelling and active substance-loading capacity and flexibility, nanogels made from natural and synthetic polymers have gained significant interest in scientific and industrial areas. In particular, the customized design and implementation of nontoxic, biocompatible, and biodegradable micro/nano carriers makes their usage very feasible for a range of biomedical applications, including drug delivery, tissue engineering, and bioimaging. The design and application methodologies of nanogels are outlined in this review. Additionally, the most recent advancements in nanogel biomedical applications are discussed, with particular emphasis on applications for the delivery of drugs and biomolecules.

Encapsulation of Bioactive Peptides by Spray-Drying and Electrospraying

Bioactive peptides derived from enzymatic hydrolysis are gaining attention for the production of supplements, pharmaceutical compounds, and functional foods. However, their inclusion in oral delivery systems is constrained by their high susceptibility to degradation during human gastrointestinal digestion. Encapsulating techniques can be used to stabilize functional ingredients, helping to maintain their activity after processing, storage, and digestion, thus improving their bioaccessibility. Monoaxial spray-drying and electrospraying are common and economical techniques used for the encapsulation of nutrients and bioactive compounds in both the pharmaceutical and food industries. Although less studied, the coaxial configuration of both techniques could potentially improve the stabilization of protein-based bioactives via the formation of shell-core structures. This article reviews the application of these techniques, both monoaxial and coaxial configurations, for the encapsulation of bioactive peptides and protein hydrolysates, focusing on the factors affecting the properties of the encapsulates, such as the formulation of the feed solution, selection of carrier and solvent, as well as the processing conditions used. Furthermore, this review covers the release, retention of bioactivity, and stability of peptide-loaded encapsulates after processing and digestion.

Minimalist Nanocomplex with Dual Regulation of Endothelial Function and Inflammation for Targeted Therapy of Inflammatory Vascular Diseases

Vascular disorders, characterized by vascular endothelial dysfunction combined with inflammation, are correlated with numerous fatal diseases, such as coronavirus disease-19 and atherosclerosis. Achieving vascular normalization is an urgent problem that must be solved when treating inflammatory vascular diseases. Inspired by the vascular regulatory versatility of nitric oxide (NO) produced by endothelial nitric oxide synthase (eNOS) catalyzing l-arginine (l-Arg), the eNOS-activating effects of l-Arg, and the powerful anti-inflammatory and eNOS-replenishing effects of budesonide (BUD), we constructed a bi-prodrug minimalist nanoplatform co-loaded with BUD and l-Arg via polysialic acid (PSA) to form BUD-l-Arg@PSA. This promoted vascular normalization by simultaneously regulating vascular endothelial dysfunction and inflammation. Mediated by the special affinity between PSA and E-selectin, which is highly expressed on the surface of activated endothelial cells (ECs), BUD-l-Arg@PSA selectively accumulated in activated ECs, targeted eNOS expression and activation, and promoted NO production. Consequently, the binary synergistic regulation of the NO/eNOS signaling pathway occurred and improved vascular endothelial function. NO-induced nuclear factor-kappa B alpha inhibitor (IκBα) stabilization and BUD-induced nuclear factor-kappa B (NF-κB) response gene site occupancy achieved dual-site blockade of the NF-κB signaling pathway, thereby reducing the inflammatory response and inhibiting the infiltration of inflammation-related immune cells. In a renal ischemia-reperfusion injury mouse model, BUD-l-Arg@PSA reduced acute injury. In an atherosclerosis mouse model, BUD-l-Arg@PSA decreased atherosclerotic plaque burden and improved vasodilation. This represents a revolutionary therapeutic strategy for inflammatory vascular diseases.

Enrichment and application of extracellular nonulosonic acids containing polymers of Accumulibacter

Pseudaminic and legionaminic acids are a subgroup of nonulosonic acids (NulOs) unique to bacterial species. There is a lack of advances in the study of these NulOs due to their complex synthesis and production. Recently, it was seen that "Candidatus Accumulibacter" can produce Pse or Leg analogues as part of its extracellular polymeric substances (EPS). In order to employ a "Ca. Accumulibacter" enrichment as production platform for bacterial sialic acids, it is necessary to determine which fractions of the EPS of "Ca. Accumulibacter" contain NulOs and how to enrich and/or isolate them. We extracted the EPS from granules enriched with "Ca. Accumulibcater" and used size-exclusion chromatography (SEC) to separate them into different molecular weight (MW) fractions. This separation resulted in two high molecular weight (> 5500 kDa) fractions dominated by polysaccharides, with a NulO content up to 4 times higher than the extracted EPS. This suggests that NulOs in "Ca. Accumulibacter" are likely located in high molecular weight polysaccharides. Additionally, it was seen that the extracted EPS and the NulO-rich fractions can bind and neutralize histones. This opens the possibility of EPS and NulO-rich fractions as potential source for sepsis treatment drugs. KEY POINTS: • NulOs in "Ca. Accumulibacter" are likely located in high MW polysaccharides • SEC allows to obtain high MW polysaccharide-rich fractions enriched with NulOs • EPS and the NulOs-rich fractions are a potential source for sepsis treatment drugs.

A convergent fabrication of pH and redox dual-responsive hybrids of mesoporous silica nanoparticles for the treatment of breast cancer

Mesoporous silica nanoparticle (MSN), sodium hyaluronate (SH), silk fibroin (SS), and oxidized sodium carboxymethyl cellulose (O-CMC) hybrids were used to develop an intelligent drug delivery platform that may be employed for pH and redox-responsive bi-drug administration. The first drug, cytarabine (Cyt), was loaded with amino-functionalized mesoporous silica (MSN-NH₂) encased by the hydrogel of cystamine (Cys) and SH cross-linked by amide bonds. Hydrophobic doxorubicin (DOX) was co-loaded with Cyt/MSN-NH₂/SA in the hydrogel of SS and O-CMC in the Cyt- loaded hydrogel. Dual-responsive drug delivery may be achieved by encapsulating SS and O-CMC in a hydrogel, including Cyt/MSN-NH₂/SA/DOX/SS/O-CMC, which has acyl hydrazone bonds (-HC = N) and disulfide bond (-S-S-) exchange reaction with glutathione (GSH). Compared to hydrogels encapsulating only one drug (Cyt or DOX), cell survival analysis revealed that the newly fabricated hydrogels have significantly greater chemotherapeutic efficacy. The cell proliferation of the fabricated nanoparticles was examined in MCF-7 and MDA-MB-231 cells, which indicates that the nanoparticles effectively kill the cancer cells without affecting non-cancerous cells. Further, we effectively investigated the morphological changes, and various biochemical staining methods examined nuclear fragmentation/condensation. Furthermore, the biosafety of the nanoparticles was investigated by the in vivo animal model, which reveals that they remarkably enhanced the safety profile in various organs. These outcomes demonstrated that this nanoparticle platform was a promising beneficial agent for improving breast cancer treatment.

Safe magnetic resonance imaging on biocompatible nanoformulations

Magnetic resonance imaging (MRI) holds promise for the early clinical diagnosis of various diseases, but most clinical MR techniques require the use of a contrast medium. Several nanomaterial (NM) mediated contrast agents (CAs) are widely used as T1- and T2-based MR contrast agents for clinical and non-clinical applications. Unfortunately, most NM-based CAs are toxic or non-biocompatible, restricting their practical/clinical applications. Therefore, the development of nontoxic and biocompatible CAs for clinical MRI diagnosis is highly desired. To this end, several biocompatible and biomimetic strategies have been developed to offer long blood circulation time, significant biocompatibility, in vivo biodistribution and high contrast ability for efficient imaging. However, detailed review reports on biocompatible NMs, specifically for MR imaging have not yet been summarized. Thus, in the present review we summarize  various surface coating strategies (such as polymers, proteins, cell membranes, etc.) to achieve biocompatible NPs, providing a detailed discussion of advances and future prospects for safe MRI imaging.

Current Advances of Polysaccharide-Based Nanogels and Microgels in Food and Biomedical Sciences

Polysaccharides are natural polymers with hydrophilic, biocompatible and biodegradable characteristics and have many opportunities in the food and pharmaceutical sectors. This review focuses on the field of nano and microstructures whose internal structure is based on networked polysaccharide chains in 3D i.e., polysaccharide nanogels (NGs) and microgels (MGs). As it is observed the number of articles on NGs and MGs in peer reviewed scientific journals has been increasing over the last two decades. At the same time, the relative contribution of polysaccharides in this field is gaining place. This review focuses on the different applied methods for the fabrication of a variety of polysaccharide-based NGs and MGs and aims to highlight the recent advances on the subject and present their potentials and properties with regards to their integration in aspects of medicinal and food sciences. The presentation of the recent advances in the application of polysaccharide NGs and MGs is divided in materials with potential as emulsion stabilizers and materials with potential as carriers of bioactives. For applications in the medical sector the division is based on the fabrication processes and includes self-assembled, electrostatically complexed/ionically crosslinked and chemically crosslinked NGs and MGs. It is concluded that many advances are expected in the application of these polysaccharide-based materials and in particular as nutrient-loaded emulsion stabilizers, viscosity modifiers and co-assembled structures in combination with proteins.

Microneedle-Based Natural Polysaccharide for Drug Delivery Systems (DDS): Progress and Challenges

In this focused progress review, the most widely accepted methods of transdermal drug delivery are hypodermic needles, transdermal patches and topical creams. However, microneedles (MNs) (or microneedle arrays) are low-invasive 3D biomedical constructs that bypass the skin barrier and produce systemic and localized pharmacological effects. In the past, biomaterials such as carbohydrates, due to their physicochemical properties, have been extensively used to manufacture microneedles (MNs). Due to their wide range of functional groups, carbohydrates enable the design and development of tunable properties and functionalities. In recent years, numerous microneedle products have emerged on the market, although much research needs to be undertaken to overcome the various challenges before the successful introduction of microneedles into the market. As a result, carbohydrate-based microarrays have a high potential to achieve a future step in sensing, drug delivery, and biologics restitution. In this review, a comprehensive overview of carbohydrates such as hyaluronic acid, chitin, chitosan, chondroitin sulfate, cellulose and starch is discussed systematically. It also discusses the various drug delivery strategies and mechanical properties of biomaterial-based MNs, the progress made so far in the clinical translation of carbohydrate-based MNs, and the promotional opportunities for their commercialization. In conclusion, the article summarizes the future perspectives of carbohydrate-based MNs, which are considered as the new class of topical drug delivery systems.

Fabrication and biomedical applications of Arabinoxylan, Pectin, Chitosan, Soy protein, and Silk fibroin hydrogels via laccase - ferulic acid redox chemistry

The unique physiochemical properties and the porous network architecture of hydrogel seek the attention to be explored in broad range of fields. In the last decade, numerous studies on the development of enzymatically cross-linked hydrogels have been elucidated. Implementing enzyme based cross-linking for fabrication of biomaterials over other crosslinking methods harbor various advantages, especially hydrogels designed using laccase exhibits mild reaction environment, high cross-linking efficiency and less toxicity. To our knowledge this is the first report reviewing the formulation of laccase mediated cross-linking for hydrogel preparation. Here, laccase catalyzed synthesis of hydrogel using polysaccharide viz. arabinoxylan, sugar beet pectin, galactomannan, chitosan etc. and proteins namely soy protein, gelatin, silk fibroin were discussed on highlighting their mechanical properties and its possible field of application. We have summarized the role of phenolic acids in laccase mediated crosslinking particularly ferulic acid which is a component of lignocellulose, serving cell rigidity via crosslinkage. The review also discusses on various biomedical applications such as controlled protein release, tissue engineering, and wound healing. It is anticipated that this review will give a detailed information on different laccase mediated reaction strategies that can be applied for the synthesis of various new biomaterials with tailor made properties.

Protein-Based Nanohydrogels for Bioactive Delivery

Hydrogels possess a unique three-dimensional, cross-linked network of polymers capable of absorbing large amounts of water and biological fluids without dissolving. Nanohydrogels (NGs) or nanogels are composed of diverse types of polymers of synthetic or natural origin. Their combination is bound by a chemical covalent bond or is physically cross-linked with non-covalent bonds like electrostatic interactions, hydrophobic interactions, and hydrogen bonding. Its remarkable ability to absorb water or other fluids is mainly attributed to hydrophilic groups like hydroxyl, amide, and sulphate, etc. Natural biomolecules such as protein- or peptide-based nanohydrogels are an important category of hydrogels which possess high biocompatibility and metabolic degradability. The preparation of protein nanohydrogels and the subsequent encapsulation process generally involve use of environment friendly solvents and can be fabricated using different proteins, such as fibroins, albumin, collagen, elastin, gelatin, and lipoprotein, etc. involving emulsion, electrospray, and desolvation methods to name a few. Nanohydrogels are excellent biomaterials with broad applications in the areas of regenerative medicine, tissue engineering, and drug delivery due to certain advantages like biodegradability, biocompatibility, tunable mechanical strength, molecular binding abilities, and customizable responses to certain stimuli like ionic concentration, pH, and temperature. The present review aims to provide an insightful analysis of protein/peptide nanohydrogels including their preparation, biophysiochemical aspects, and applications in diverse disciplines like in drug delivery, immunotherapy, intracellular delivery, nutraceutical delivery, cell adhesion, and wound dressing. Naturally occurring structural proteins that are being explored in protein nanohydrogels, along with their unique properties, are also discussed briefly. Further, the review also covers the advantages, limitations, overview of clinical potential, toxicity aspects, stability issues, and future perspectives of protein nanohydrogels.

Natural biomaterials in brain repair: A focus on collagen

Biomaterials derived from natural resources have increasingly been used for versatile applications in the central nervous system (CNS). Thanks to their biocompatibility and biodegradability, natural biomaterials offer vast possibilities for future clinical repair strategies for the CNS. These materials can be used for diverse applications such as hydrogels to fill the tissue cavities, microparticles to deliver drugs across the blood-brain barrier, and scaffolds to transplant stem cells. In this review, various uses of prominent protein and polysaccharide biomaterials, with a special focus on collagen, in repair and regenerative applications for the brain are summarized together with their individual advantages and disadvantages.

Curcumin-loaded core-shell biopolymer nanoparticles produced by the pH-driven method: Physicochemical and release properties

In this study, core-shell biopolymer nanoparticles were fabricated for the encapsulation and delivery of curcumin using a pH-driven method. The influences of the coating composition on the physicochemical properties and curcumin release characteristics of the core-shell nanoparticles were studied. Fourier transform infrared spectroscopy and X-ray diffraction analyses indicated that curcumin was encapsulated in an amorphous state inside the nanoparticles. Particle size and ζ-potential measurements indicated that the biopolymer nanoparticles were relatively stable under different environmental conditions: long term storage, heating, pH changes and salt. The DPPH radical scavenging activity of the curcumin was increased after encapsulation within the nanoparticles, whereas the gastrointestinal release of curcumin was prolonged. These results were attributed to the ability of alginate and NaCas to form a thick layer around the nanoparticles, which increased the steric and electrostatic repulsion between them, as well as inhibiting the release of curcumin.

Recent Advances of Taxol-Loaded Biocompatible Nanocarriers Embedded in Natural Polymer-Based Hydrogels

The discovery of paclitaxel (PTX) has been a milestone in anti-cancer therapy and has promoted the development and marketing of various formulations that have revolutionized the therapeutic approach towards several malignancies. Despite its peculiar anti-cancer activity, the physico-chemical properties of PTX compromise the administration of the compound in polar media. Because of this, since the development of the first Food and Drug Administration (FDA)-approved formulation (Taxol®), consistent efforts have been made to obtain suitable delivery systems able to preserve/increase PTX efficacy and to overcome the side effects correlated to the presence of some excipients. The exploitation of natural polymers as potential materials for drug delivery purposes has favored the modulation of the bioavailability and the pharmacokinetic profiles of the drug, and in this regard, several formulations have been developed that allow the controlled release of the active compound. In this mini-review, the recent advances concerning the design and applications of natural polymer-based hydrogels containing PTX-loaded biocompatible nanocarriers are discussed. The technological features of these formulations as well as the therapeutic outcome achieved following their administration will be described, demonstrating their potential role as innovative systems to be used in anti-tumor therapy.