Hyaluronic Acid Nanoparticles as Nanomedicine for Treatment of Inflammatory Diseases

Advances and principles of hyaluronic acid production, extraction, purification, and its applications: A review

Hyaluronic acid (HA) is a linear, unbranched polysaccharide composed of repeating disaccharide units of N-acetyl-d-glucosamine and D-glucuronic acid. It plays a crucial role in promoting soft tissue growth, elasticity, and scar reduction. The growing demand for HA in pharmaceutical and cosmetic applications has provoked extensive research into diverse production strategies. Current efforts focus on bacterial and yeast fermentation. However, the extraction process presents a significant challenge due to the complex nature of source materials like fermentation broth, which contains numerous components and solutes. Achieving high extraction yields and purity requires careful consideration of extraction techniques. This study provides a comprehensive overview of the primary methodologies employed for HA production, elaborating on the advantages and disadvantages of each approach. Additionally, it highlights recent advancements in HA extraction and purification, with a particular emphasis on bacterial sources and the applications of HA. This review critically evaluates current HA production strategies, identifies key challenges hindering scalability and efficiency, and discusses innovative solutions under development to overcome these limitations.

Combating antimicrobial resistance: In vitro and in vivo efficacy of berberine-loaded metal-organic frameworks with hyaluronic acid coating

To create a new antimicrobial delivery system, we synthesized UiO-66-NH₂ (UN) metal-organic frameworks (MOF) loaded with berberine (UNB) and coated with hyaluronic acid (UNB@H) as a novel antimicrobial delivery system. Physicochemical techniques were used to successfully produce and characterize UNB@H nanoparticles, confirming their uniform size, excellent encapsulation efficiency, and structural integrity. pH-responsive drug release was 69.47% after 72 h, observed, with a sustained release under acidic conditions. The findings showed that UNB and UNB@H have extremely strong antibacterial activity. The findings of anti-biofilm activity tests showed that UNB@H significantly inhibited biofilms and downregulated the expression of efflux pump genes (MexA, MexB, norA, norB) and biofilm-related genes (icaA, icaB, ndvB, pelA) in all strains. The toxicity results indicated that the UNB@H exhibited 97.55 % cytotoxicity on HFF cells at a concentration of 50 μg/ml and 3.9% hemolysis, demonstrating excellent hemocompatibility. Additionally, H&E analysis confirmed in vivo wound infection investigations that demonstrated efficient infection control and faster healing. These results highlight UNB@H's potential as a multipurpose platform to fight antimicrobial resistance (AMR) by focusing on resistance mechanisms, biofilm formation, and offering biocompatible treatments for MDR infections.

Studying the Effect of Reducing Agents on the Properties of Gold Nanoparticles and Their Integration into Hyaluronic Acid Hydrogels

Gold nanoparticles (Au NPs) are a promising target for research due to their small size and the resulting plasmonic properties, which depend, among other things, on the chosen reducer. This is important because removing excess substrate from the reaction mixture is problematic. However, Au NPs are an excellent component of various materials, enriching them with their unique features. One example is hydrogels, which provide a good, easily modifiable base for multiple applications such as cosmetics. For this purpose, various compounds, including hyaluronic acid (HA) and its derivatives, are distinguished by their high water-binding capacity and many characteristics resulting from their natural origin in organisms, including biocompatibility, biodegradability, and tissue regeneration. In this work Au NPs were synthesized using a green chemistry method, either by using onion extract as a reductant or chemically reducing them with sodium citrate. A complete characterization of the nanoparticles was carried out using the following methods: Fourier-Transform Infrared Spectroscopy (FT-IR), Electrophoretic (ELS), and Dynamic Light Scattering (DLS) as well as Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM). Their antioxidant activity was also tested using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). The results showed that the synthesized nanoparticles enrich the hydrogels with antioxidant properties and new surface properties (depending on the reducing agent, they can be more hydrophilic or hydrophobic). Preliminary observations indicated low cytotoxicity of the nanomaterials in both liquid form and as a hydrogel component, as well as their lack of penetration through pig skin. The cosmetic properties of hydrogel masks were also confirmed, such as increasing skin hydration.

Bioactive Compounds and Their Chondroprotective Effects for Osteoarthritis Amelioration: A Focus on Nanotherapeutic Strategies, Epigenetic Modifications, and Gut Microbiota

In degenerative joint disease like osteoarthritis (OA), bioactive compounds like resveratrol, epigallocatechin gallate, curcumin, and other polyphenols often target various signalling pathways, including NFκB, TGFβ, and Wnt/β-catenin by executing epigenetic-modifying activities. Epigenetic modulation can target genes of disease pathophysiology via histone modification, promoter DNA methylation, and non-coding RNA expression, some of which are directly involved in OA but have been less explored. OA patients often seek options that can improve the quality of their life in addition to existing treatment with nonsteroidal anti-inflammatory drugs (NSAIDs). Although bioactive and natural compounds exhibit therapeutic potential against OA, several disadvantages loom, like insolubility and poor bioavailability. Nanoformulated bioactive compounds promise a better way to alleviate OA since they also control systemic events, including metabolic, immunological, and inflammatory responses, by modulating host gut microbiota that can regulate OA pathogenesis. Recent data suggest gut dysbiosis in OA. However, limited evidence is available on the role of bioactive compounds as epigenetic and gut modulators in ameliorating OA. Moreover, it is not known whether the effects of polyphenolic bioactive compounds on gut microbial response are mediated by epigenetic modulatory activities in OA. This narrative review highlights the nanotherapeutic strategies utilizing bioactive compounds, reporting their effects on chondrocyte growth, metabolism, and epigenetic modifications in osteoarthritis amelioration.

Targeting inflammation with hyaluronic acid-based micro- and nanotechnology: A disease-oriented review

Inflammation is a pivotal immune response in numerous diseases and presents therapeutic challenges. Traditional anti-inflammatory drugs and emerging cytokine inhibitors encounter obstacles such as limited bioavailability, poor tissue distribution, and adverse effects. Hyaluronic acid (HA), a versatile biopolymer, is widely employed to deliver therapeutic agents, including anti-inflammatory drugs, genes, and cell therapies owing to its unique properties, such as hydrophilicity, biodegradability, and safety. HA interacts with cell receptors to initiate processes such as angiogenesis, cell proliferation, and immune regulation. HA-based drug delivery systems offer dual strategies for effective inflammation management, capitalizing on passive and active mechanisms. This synergy permits the mitigation of inflammation by lowering the doses of anti-inflammatory drugs and their off-target adverse effects. A diverse array of micro- and nanotechnology techniques enable the fabrication of tailored HA-engineered systems, including hydrogels, microgels, nanogels, microneedles, nanofibers, and 3D-printed scaffolds, for diverse formulations and administration routes. This review explores recent insights into HA pharmacology in inflammatory conditions, material design, and fabrication methods, as well as its applications across a spectrum of inflammatory diseases, such as atherosclerosis, psoriasis, dermatitis, wound healing, rheumatoid arthritis, osteoarthritis, inflammatory bowel disease, and colitis, highlighting its potential for clinical translation.

Hyaluronic Acid in Nanopharmaceuticals: An Overview

Hyaluronic acid (HA) is a naturally occurring, long, unbranched polysaccharide that plays a critical role in maintaining skin structure and hydration. Its unique properties make it a valuable component in the field of nanopharmaceuticals. The combination of HA into nanopharmaceuticals enhances its ability to interact with various therapeutic agents, improving the delivery and efficacy of drugs. HA-based nanoparticles, including solid lipid nanoparticles, and polymeric nanogels, offer controlled release, enhanced stability, and targeted delivery of therapeutic agents. These innovations significantly improve therapeutic outcomes and reduce side effects, making HA an essential tool in modern medicine. In general, HA-modified liposomes enhance drug encapsulation and targeting, while HA-modified solid lipid nanoparticles (SLNs) provide a solid lipid core for drug encapsulation, offering controlled release and stability. This article provides an overview of the potential applications and recent advancements of HA in nanopharmaceuticals, emphasizing its significant impact on the evolving field of targeted drug delivery and advanced therapeutic strategies. By delving into the unique properties of HA and its compatibility with various therapeutic agents, this review underscores the promising potential of HA in revolutionizing nanopharmaceuticals.

Strategies for the development of metalloimmunotherapies

Metal ions play crucial roles in the regulation of immune pathways. In fact, metallodrugs have a long record of accomplishment as effective treatments for a wide range of diseases. Here we argue that the modulation of interactions of metal ions with molecules and cells involved in the immune system forms the basis of a new class of immunotherapies. By examining how metal ions modulate the innate and adaptive immune systems, as well as host-microbiota interactions, we discuss strategies for the development of such metalloimmunotherapies for the treatment of cancer and other immune-related diseases.

Anti-inflammatory and antioxidant effects on skin based on supramolecular hyaluronic acid-ectoin

We addressed the damage caused by internal and external factors on the skin, as well as the aging phenomenon caused by delayed repair after damage. We prepared supramolecular hyaluronic acid-ectoin (HA-ECT) by combining theoretical calculations and experimental research, using intermolecular forces between hyaluronic acid and ectoin. This supramolecule has good stability, safety, and skin permeability and can penetrate the stratum corneum of the skin, reaching the epidermis and dermis of the skin. Compared with ectoin, the permeability of the supramolecule HA-ECT was 3.39-fold higher. Supramolecular HA-ECT can promote the proliferation of keratinocytes and fibroblasts, significantly increase the content of type collagen-I, reduce the expression of inflammatory factors in keratinocytes, and enhance skin hydration and repair effects. HA-ECT can reduce intracellular reactive oxygen species and inhibit the expression of matrix metalloproteinase-1 (reduced by 1.27-fold) to improve skin photoaging. Therefore, supramolecular HA-ECT has potential application in the field of cosmetics for skin antioxidants, anti-aging, and repair.

Hyaluronic Acid Nanoparticles with Parameters Required for In Vivo Applications: From Synthesis to Parametrization

Hyaluronic acid is an excellent biocompatible material for in vivo applications. Its ability to bind CD44, a cell receptor involved in numerous biological processes, predetermines HA-based nanomaterials as unique carrier for therapeutic and theranostic applications. Although numerous methods for the synthesis of hyaluronic acid nanoparticles (HANPs) are available today, their low reproducibility and wide size distribution hinder the precise assessment of the effect on the organism. A robust and reproducible approach for producing HANPs that meet strict criteria for in vivo applications (e.g., to lung parenchyma) remains challenging. We designed and evaluated four protocols for the preparation of HANPs with those required parameters. The HA molecule was cross-linked by novel combinations of carbodiimide, and four different amine-containing compounds resulted in monodisperse HANPs with a low polydispersity index. By a complex postsynthetic characterization, we confirmed that the prepared HANPs meet the criteria for inhaled therapeutic delivery and other in vivo applications.

Hyaluronic acid as a tumor progression agent and a potential chemotherapeutic biomolecule against cancer: A review on its dual role

Hyaluronic acid is a major constituent of the extracellular matrix of vertebrate tissue that provides mechanical support to cells and acts as a mediator in regulation of necessary biochemical process essential for maintenance of tissue homeostasis. The variation in quantity of hyaluronic acid content in tissues is often associated with different pathological conditions. It is associated with tumor aggression and progression as it plays crucial role in regulating different aspects of tumorigenesis and several defined hallmarks of cancer. It assists in tumor progression by undergoing extracellular remodeling to establish tumor microenvironment which restricts the delivery of cytotoxic drugs to neoplastic cells due to increase in interstitial pressure. Hyaluronic acid catabolic and anabolic genes and low-molecular weight hyaluronic acid play significant role in the establishing tumor microenvironment by assisting in cell proliferation, metastasis and invasion. On the other hand, it is also used as an effective drug-delivery platform in cancer therapies as its biocompatibility and biodegradability lower the toxicity of chemotherapeutic drugs and increase drug retention. High-molecular weight hyaluronic acid-bioconjugates specifically bind with hyaladherins, facilitating targeted drug delivery and also exert anti-inflammatory properties. This review also highlights the market and patent trends in the development of effective chemotherapeutic hyaluronic acid formulations and the current scenario regarding clinical trials.

An infection-microenvironment-targeted and responsive peptide-drug nanosystem for sepsis emergency by suppressing infection and inflammation

Sepsis is a life-threatening emergency that causes millions of deaths every year due to severe infection and inflammation. Nevertheless, current therapeutic regimens are inadequate to promptly address the vast diversity of potential pathogens. Omiganan, an antimicrobial peptide, has shown promise for neutralizing endotoxins and eliminating diverse pathogens. However, its clinical application is hindered by safety and stability concerns. Herein, we present a nanoscale drug delivery system (Omi-hyd-Dex@HA NPs) that selectively targets infectious microenvironments (IMEs) and responds to specific stimuli for efficient intervention in sepsis. The system consists of omiganan-dexamethasone conjugates linked by hydrazone bonds which self-assemble into nanoparticles coated with a hyaluronic acid (HA). The HA coating not only facilitates IMEs-targeting through interaction with intercellular-adhesion-molecule-1 on inflamed endotheliocytes, but also improves the biosafety of the nanosystem and enhances drug accumulation in primary infection sites triggered by hyaluronidase. The nanoparticles release dual drugs in IMEs through pH-sensitive cleavage of hydrazone bonds to eradicate pathogens and suppress inflammation. In multiple tissue infection and sepsis animal models, Omi-hyd-Dex@HA NPs exhibited rapid source control and comprehensive inflammation reduction, thereby preventing subsequent fatal complications and significantly improving survival outcomes. The bio-responsive and self-delivering nanosystem offers a promising strategy for systemic sepsis treatment in emergencies.

Remdesivir-Loaded Nanoliposomes Stabilized by Chitosan/Hyaluronic Acid Film with a Potential Application in the Treatment of Coronavirus Infection

An object of the present study was the development of liposomes loaded with the medicine Veklury® (remdesivir) stabilized by electrostatic adsorption of polysaccharide film formed from chitosans with different physicochemical characteristics and hyaluronic acid. The functionalization of the structures was achieved through the inclusion of an aptamer (oligonucleotide sequence) with specific affinity to the spike protein of the human coronavirus HCoV-OC43. The hydrodynamic size, electrokinetic potential and stability of the structures were evaluated at each step in the procedure. The encapsulation efficiency and loaded amount of remdesivir (99% and 299 µg/mL) were estimated by UV-vis spectroscopy. Our investigations showed manifestation of promising tendencies for prolonged periods of the drug release and increased effectiveness of its antiviral action. Among all studied versions of the delivery system, the most distinguished and suitable in a model coronavirus therapy are the liposomes formed from chitosan oligosaccharides. The cytotoxicity of the liposomes was determined against the HCT-8 cell line. A cytopathic effect inhibition test was used for the assessment of the antiviral activity of the compounds. The virucidal activity and the effect on the viral adsorption of the samples were reported by the end-point dilution method, and the alteration in viral titer was determined as Δlgs compared to untreated controls. The redox-modulating properties of the nanoparticles were studied in vitro in certain/several/a few chemical model systems. Our investigations showed a manifestation of promising tendencies for a prolonged effect of the drug release and increased effectiveness of its antiviral action.

Computational Study of Complex Formation between Hyaluronan Polymers and Polyarginine Peptides at Various Ratios

Hyaluronic acid, a naturally occurring carbohydrate biopolymer in human tissues, finds wide application in cosmetics, medicine, and material science. Its anionic properties play a crucial role in its interaction with positively charged macromolecules and ions. Among these macromolecules, positively charged arginine molecules or polyarginine peptides demonstrate potential in drug delivery when complexed with hyaluronan. This study aimed to compare and elucidate the results of both experimental and computational investigations on the interactions between hyaluronic acid polymers and polyarginine peptides. Experimental findings revealed that by varying the length of polyarginine peptides and the molar ratio, it is possible to modulate the size, solubility, and stability of hyaluronan-arginine particles. To further explore these interactions, molecular dynamics simulations were conducted to model the complexes formed between hyaluronic acid polymers and arginine peptides. The simulations are considered in different molar ratios and lengths of polyarginine peptides. By analysis of the data, we successfully determined the shape and size of the resulting complexes. Additionally, we identified the primary driving forces behind complex formation and explained the observed variations in peptide interactions with hyaluronan.

Molecular insights of anti-diabetic compounds and its hyaluronic acid conjugates against aldose reductase enzyme through molecular modeling and simulations study-a novel treatment option for inflammatory diabetes

CONTEXT

Chronic inflammation is a risk factor for diabetes, but it can also be a complication of diabetes, leading to severe diabetes and causing many other clinical manifestations. Inflammation is a major emerging complication in both type I and type II diabetes, which causes increasing interest in targeting inflammation to improve and control diabetes. Diabetes with insulin resistance and impaired glucose utilization in humans and their underlying mechanism is not fully understood. But a growing understanding of the intricacy of the insulin signaling cascade in diabetic inflammatory cells reveals potential target genes and their proteins responsible for severe insulin resistance. With this baseline concept, the current project explores the binding affinities of the hyaluronic acid anti-diabetic compounds conjugates to such target proteins in diabetic inflammatory cells and their molecular geometries. A range of 48 anti-diabetic compounds was screened against aldose reductase binding pocket 3 protein target through in silico molecular docking, and results revealed that three compounds viz, metformin (CID:4091), phenformin (CID:8249), sitagliptin (CID:4,369,359), possess significant binding affinity out of 48 chosen drugs. Further, these three anti-diabetic compounds were conjugated with hyaluronic acid (HA), and their binding affinity and their molecular geometrics towards aldose reductase enzyme were screened compared with the free form of the drug. The molecular geometries of three shortlisted drugs (metformin, phenformin, sitagliptin) and their HA conjugates were also explored through density functional theory studies, and it proves their good molecular geometry towards pocket 3 of aldose reductase target. Further, MD simulation trajectories affirm that HA conjugates possess good binding affinity and simulation trajectories with protein target aldose reductase than a free form of the drug. Our current study unravels the new mechanism of drug targeting for diabetes through HA conjugation for inflammatory diabetes. HA conjugates act as novel drug candidates for treating inflammatory diabetes; however, it needs further human clinical trials.

METHODS

For ligand structure, PubChem, ACD chem sketch, and online structure file generator platform are utilized for ligand preparation. Target protein aldose reductase obtained from protein database (PDB). For molecular docking analysis, AutoDock Vina (Version 4) was utilized. pKCSM online server used to predict ADMET properties of the above three shortlisted drugs from the docking study. Using mol-inspiration software (version 2011.06), three shortlisted compounds' bioactivity scores were predicted. DFT analysis for three shortlisted anti-diabetic drugs and their hyaluronic acid conjugates were calculated using a functional B3LYP set of Gaussian 09 software. Molecular dynamics simulation calculations for six chosen protein-ligand complexes were done through YASARA dynamics software and AMBER14 force field.

Doxorubicin-Loaded Platelet Decoys for Enhanced Chemoimmunotherapy Against Triple-Negative Breast Cancer in Mice Model

Introduction

Triple-negative breast cancer (TNBC) is a highly aggressive subtype with a poor prognosis. Current single-agent checkpoint therapy has limited effectiveness in TNBC patients. In this study, we developed doxorubicin-loaded platelet decoys (PD@Dox) for chemotherapy and induction of tumor immunogenic cell death (ICD). By combining PD-1 antibody, PD@Dox has the potential to enhance tumor therapy through chemoimmunotherapy in vivo.

Methods

Platelet decoys were prepared using 0.1% Triton X-100 and co-incubated with doxorubicin to obtain PD@Dox. Characterization of PDs and PD@Dox was performed using electron microscopy and flow cytometry. We evaluated the properties of PD@Dox to retain platelets through sodium dodecyl sulfate-polyacrylamide gel electrophoresis, flow cytometry, and thromboelastometry. In vitro experiments assessed drug-loading capacity, release kinetics, and the enhanced antitumor activity of PD@Dox. The mechanism of PD@Dox was investigated through cell viability assays, apoptosis assays, Western blot analysis, and immunofluorescence staining. In vivo studies were performed using a TNBC tumor-bearing mouse model to assess the anticancer effects.

Results

Electron microscopic observations confirmed that platelet decoys and PD@Dox exhibited a round shape similar to normal platelets. Platelet decoys demonstrated superior drug uptake and loading capacity compared to platelets. Importantly, PD@Dox retained the ability to recognize and bind tumor cells. The released doxorubicin induced ICD, resulting in the release of tumor antigens and damage-related molecular patterns that recruit dendritic cells and activate antitumor immunity. Notably, the combination of PD@Dox and immune checkpoint blockade therapy using PD-1 antibody achieved significant therapeutic efficacy by blocking tumor immune escape and promoting ICD-induced T cell activation.

Conclusion

Our results suggest that PD@Dox, in combination with immune checkpoint blockade therapy, holds promise as a potential strategy for TNBC treatment.

Impact of nanotechnology on the oral delivery of phyto-bioactive compounds

Nanotechnology is an advanced field that has remarkable nutraceutical and food applications. Phyto-bioactive compounds (PBCs) play critical roles in promoting health and disease treatment. However, PBCs generally encounter several limitations that delay their widespread application. For example, most PBCs have low aqueous solubility, poor biostability, poor bioavailability, and a lack of target specificity. Moreover, the high concentrations of effective PBC doses also limit their application. As a result, encapsulating PBCs into an appropriate nanocarrier may increase their solubility and biostability and protect them from premature degradation. Moreover, nanoencapsulation could improve absorption and prolong circulation with a high opportunity for targeted delivery that may decrease unwanted toxicity. This review addresses the main parameters, variables, and barriers that control and affect oral PBC delivery. Moreover, this review discusses the potential role of biocompatible and biodegradable nanocarriers in improving the water solubility, chemical stability, bioavailability, and specificity/selectivity of PBCs.

State-of-the-art advancement of surface functionalized layered double hydroxides for cell-specific targeting of therapeutics

Over the years, layered double hydroxides (LDHs) hold a specific position in biomedicine due to their tunable chemical composition and appropriate structural properties. However, LDHs lack adequate sensitivity for active targeting because of less active surface area and low mechanical strength in physiological conditions. The exploitation of eco-friendly materials, such as chitosan (CS), for surface engineering of LDHs, whose payloads are transferred only under certain conditions, can help develop stimuli-responsive materials owing to high biosafety and unique mechanical strength. We aim to render a well-oriented scenario toward the latest achievements of a bottom-up technology relying on the surface functionalization of LDHs to fabricate functional formulations with promoted bio-functionality and high encapsulation efficiency for various bioactives. Many efforts have been devoted to critical aspects of LDHs, including systemic biosafety and the suitability for developing multicomponent systems via integration with therapeutic modalities, which are thoroughly discussed herein. In addition, a comprehensive discussion was provided for the recent progress in the emergence of CS-coated LDHs. Finally, the challenges and future perspectives in the fabrication of efficient CS-LDHs in biomedicine are considered, with a special focus on cancer treatment.

Application of Stichopus hermanni Nanoparticle Gel in the Healing of Traumatic Ulcers

OBJECTIVE

 The aim of this research was to investigate the use of Stichopus herrmanni nanoparticle gel on the ulcer healing process by observing blood vessels, fibroblasts, and Collagen type-I (COL-1) expression on the 4 and 7th days after trauma.

MATERIALS AND METHODS

 Gold sea cucumber (Stichopus herrmanni) powder was processed by freeze-drying method, then by high-energy milling to form nanoparticle size, and then with CMC 2% to make hydrogel. Traumatic ulcers were formed by induction using a burner. Five groups of male Wistar rats, each consisting of six tails, were divided into a negative control group that was given a placebo, the positive control group was given 0.2% hyaluronic acid, and the treatment group was given gold sea cucumbers with concentrations of 0.135, 0.27, and 0.54% (SH1-SH2-SH3). Fibroblast and blood vessels were examined with hematoxylin-eosin on day 3 and 7, while COL-1 expression was examined with immunohistochemistry on day 7. The rats' mucosa was taken on the 3rd and 7th days after the traumatic ulcer was formed.

STATISTICAL ANALYSIS

 The data were analyzed using a one-way analysis of variance followed by a post-hoc test with a p less than 0.05.

RESULTS

 Nanoparticles gel freeze-drying of Stichopus herrmanni increased blood vessels on day 3. Angiogenesis continued to occur, which resulted in increased fibroblast and COL-1 expression on day 7.

CONCLUSIONS

 The application of Stichopus herrmanni nanoparticle gel at 0.27% effectively increased the number of blood vessels, fibroblasts, and COL-1 expression in healing traumatic ulcers.

Tumor-targeted miRNA nanomedicine for overcoming challenges in immunity and therapeutic resistance

miRNA are critical messengers in the tumor microenvironment (TME) that influence various processes leading to immune suppression, tumor progression, metastasis and resistance. Strategies to modulate miRNAs in the TME have important implications in overcoming these challenges. However, miR delivery to specific cells in the TME has been challenging. This review discusses nanomedicine strategies to achieve cell-specific delivery of miRNAs. The key goal of delivery is to activate the tumor immune landscape as well as to prevent chemotherapy resistance. Specifically, the use of hyaluronic acid-based nanoparticle miRNA delivery to the TME is discussed. The discussion is focused on miRNA-125b for reprogramming tumor-associated macrophages to overcome immunosuppression and miRNA-let-7b to overcome resistance to anticancer chemotherapeutics because both these miRNAs have been extensively evaluated for delivery with hyaluronic acid-based delivery systems.

Dynamic Effects of Endo-Exogenous Stimulations on Enzyme-Activatable Polymeric Nanosystems with Photo-Sono-Chemo Synergy

Activatable polymeric nanosystems have attracted great interest, and their interactions with endo-exogenous stimulations are highly vital for therapeutic efficacy, which urgently needs systematic study. Herein we focus on systematically investigating these interactions on an enzyme-nanosystem model, the tumor-overexpressed hyaluronidase (HAase) and the doxorubicin-loaded hyaluronic-acid-porphyrin nanoassemblies (DOX@HPNAs), to augment photo-sono-chemo therapies. The HAase degrades the HPNAs in acidic solution at a higher rate than that in neutral solution, which leads to structure disassembly at the nano level, chain cleavage at the molecular level, and strong radiative recovery at the energy level. Upon excitation with light and ultrasound, the enzymatically degraded sample produces ∼2.5 times more singlet oxygen than the HPNAs because of the absence of aggregation-induced quenching and ¹O₂ migration limitation. The nanosystem can be activated by trimodal stimulations (acidity, ultrasound, and HAase), exerting the controllable release behavior and high release content. Moreover, the nanosystem exhibits synergistic effects among efficient photodynamic therapy, high tissue-penetrating sonodynamic therapy, and lasting chemotherapy, which induces significant necrosis and apoptosis of cancer cells. With high compatibility, tumor-targeting ability, and fluorescent-imaging-guided capability, the nanosystem achieves the highest inhibition rate of malignant tumors than the single or dual-modal therapies. Thus, the enzyme-activatable nanosystem enables the therapeutic synergy and also provides insights to develop other polymeric nanosystems.

Advances in Hyaluronic Acid for Biomedical Applications

Hyaluronic acid (HA) is a large non-sulfated glycosaminoglycan that is the main component of the extracellular matrix (ECM). Because of its strong and diversified functions applied in broad fields, HA has been widely studied and reported previously. The molecular properties of HA and its derivatives, including a wide range of molecular weights but distinct effects on cells, moisture retention and anti-aging, and CD44 targeting, promised its role as a popular participant in tissue engineering, wound healing, cancer treatment, ophthalmology, and cosmetics. In recent years, HA and its derivatives have played an increasingly important role in the aforementioned biomedical fields in the formulation of coatings, nanoparticles, and hydrogels. This article highlights recent efforts in converting HA to smart formulation, such as multifunctional coatings, targeted nanoparticles, or injectable hydrogels, which are used in advanced biomedical application.

Microfluidic-driven mixing of high molecular weight polymeric complexes for precise nanoparticle downsizing

Chitosan (CHIT) and hyaluronic acid (HA) are two polysaccharides (PSs) with high value in several biomedical applications. In this study, we present a microfluidic method to synthetize CHIT-HA NPs to overcome the disadvantages of the dropwise approach generally used for nanoprecipitation of polyelectrolyte complexes. The proposed microfluidic approach enables to generate monodisperse suspensions of NPs with ≈100 nm of size compared to the dropwise method that generated ≈2 times bigger NPs. Finally, we evaluated the potential of obtained NPs in an inflammatory scenario. The treatment with NPs led to the reduction of the main inflammatory molecules produced by macrophages (PGE₂, IL-6, IL-8, MCAF and TNF-α) and fibroblasts (IL-1 α, PGE₂, TNF-α) stimulated with lipopolysaccharide or conditioned medium, respectively. This study demonstrates that our approach can be used to enhance the synthesis of nanocarriers based on bioactive macromolecules.

Hyaluronic acid coated teriflunomide (A771726) loaded lipid carriers for the oral management of rheumatoid arthritis

Systemic rheumatoid arthritis treatment has been associated with numerous side effects. We attempted to formulate hyaluronic acid (HA)-coated teriflunomide (TER)-loaded nanostructured lipid carriers (NLCs) that can target inflamed rheumatic joints following oral administration. In vitro evaluation including colloidal characteristics, drug release and stability studies were conducted. Also, cytotoxicity studies on THP1 and peripheral blood mononuclear cells besides testing the binding of HA coated TER-NLCs to CD44 receptors were carried out. Furthermore, pharmacokinetics following oral administration, anti-arthritic effects, hepato and nephrotoxicity of NLCs were assessed. Selected NLCs formulation was approximately 284.9 ± 3.8 nm in size with 96.89 ± 0.45% entrapment efficiency and provided a sustained release for 30 days. NLCs showed good stability that was confirmed by TEM examination. Cell culture studies revealed that HA-coated TER- NLCs showed superior cytotoxicity and binding affinity to CD44 receptors compared with TER suspension. In vivo studies demonstrated the superiority of NLCs in increasing TER bioavailability, reducing TNF-α serum levels and improving joint healing that was evidenced in both histopathological and X-ray radiographic examination. This may be attributed to the ability of HA-coated TER-NLCs to target rheumatic joints passively and actively by targeting CD44 receptors that are overexpressed in rheumatic joints.

A Review on Current Strategies for Extraction and Purification of Hyaluronic Acid

Since it is known that hyaluronic acid contributes to soft tissue growth, elasticity, and scar reduction, different strategies of producing HA have been explored in order to satisfy the current demand of HA in pharmaceutical products and formulations. The current interest deals with production via bacterial and yeast fermentation and extraction from animal sources; however, the main challenge is the right extraction technique and strategy since the original sources (e.g., fermentation broth) represent a complex system containing a number of components and solutes, which complicates the achievement of high extraction rates and purity. This review sheds light on the main pathways for the production of HA, advantages, and disadvantages, along with the current efforts in extracting and purifying this high-added-value molecule from different sources. Particular emphasis has been placed on specific case studies attempting production and successful recovery. For such works, full details are given together with their relevant outcomes.

Exploring the applications of hyaluronic acid-based nanoparticles for diagnosis and treatment of bacterial infections

Hyaluronic acid (HA) has become a topic of significant interest in drug delivery research due to its excellent properties, including biosafety, biodegradability, and nonimmunogenicity. Moreover, due to its ease of modification, HA can be used to prepare several HA‐based nanosystems using various approaches. These approaches involve conjugating/grafting of hydrophobic moieties, polyelectrolytes complexation with cationic polymers, or surface modification of various nanoparticles using HA. These nanoparticles are able to selectively deliver antibacterial drugs or diagnostic molecules into the site of infections. In addition, HA can bind with overexpressed cluster of differentiation 44 (CD44) receptors in macrophages and also can be degraded by a family of enzymes called hyaluronidase (HAase) to release drugs or molecules. By binding with these receptors or being degraded at the infection site by HAase, HA‐based nanoparticles allow enhanced and targeted antibacterial delivery. Herein, we present a comprehensive and up‐to‐date review that highlights various techniques of preparation of HA‐based nanoparticles that have been reported in the literature. Furthermore, we also discuss and critically analyze numerous types of HA‐based nanoparticles that have been employed in antibacterial delivery to date. This article offers a critical overview of the potential of HA‐based nanoparticles to overcome the challenges of conventional antibiotics in the treatment of bacterial infections. Moreover, this review identifies further avenues of research for developing multifunctional and biomimetic HA‐based nanoparticles for the treatment, prevention, and/or detection of pathogenic bacteria.

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology

Therapeutic Approaches and Drug Discovery > Emerging Technologies

Hyaluronic Acid: Known for Almost a Century, but Still in Vogue

Hyaluronic acid (HA) has a special position among glycosaminoglycans. As a major component of the extracellular matrix (ECM). This simple, unbranched polysaccharide is involved in the regulation of various biological cell processes, whether under physiological conditions or in cases of cell damage. This review summarizes the history of this molecule's study, its distinctive metabolic pathway in the body, its unique properties, and current information regarding its interaction partners. Our main goal, however, is to intensively investigate whether this relatively simple polymer may find applications in protecting against ionizing radiation (IR) or for therapy in cases of radiation-induced damage. After exposure to IR, acute and belated damage develops in each tissue depending upon the dose received and the cellular composition of a given organ. A common feature of all organ damage is a distinct change in composition and structure of the ECM. In particular, the important role of HA was shown in lung tissue and the variability of this flexible molecule in the complex mechanism of radiation-induced lung injuries. Moreover, HA is also involved in intermediating cell behavior during morphogenesis and in tissue repair during inflammation, injury, and would healing. The possibility of using the HA polymer to affect or treat radiation tissue damage may point to the missing gaps in the responsible mechanisms in the onset of this disease. Therefore, in this article, we will also focus on obtaining answers from current knowledge and the results of studies as to whether hyaluronic acid can also find application in radiation science.

Smart Lipid-Polysaccharide Nanoparticles for Targeted Delivery of Doxorubicin to Breast Cancer Cells

In this study, actively-targeted (CD44-receptors) and dual stimuli (pH/redox)-responsive lipid–polymer nanoparticles were proposed as a delivery vehicle of doxorubicin hydrochloride in triple negative breast cancer cell lines. A phosphatidylcholine lipid film was hydrated with a solution of oxidized hyaluronic acid and doxorubicin, chosen as model drug, followed by a crosslinking reaction with cystamine hydrochloride. The obtained spherical nanoparticles (mean diameter of 30 nm) were found to be efficiently internalized in cancer cells by a receptor-mediated endocytosis process, and to modulate the drug release depending on the pH and redox potential of the surrounding medium. In vitro cytotoxicity assays demonstrated the safety and efficacy of the nanoparticles in enhancing the cytotoxic effect of the free anticancer drug, with the IC₅₀ values being reduced by two and three times in MDA-MB-468 and MDA-MB-231, respectively. The combination of self-assembled phospholipid molecules with a polysaccharide counterpart acting as receptor ligand, and stimuli-responsive chemical moieties, was carried out on smart multifunctional nanoparticles able to actively target breast cancer cells and improve the in vitro anticancer activity of doxorubicin.

Nanoparticle-Based Modification of the DNA Methylome: A Therapeutic Tool for Atherosclerosis?

Cardiovascular epigenomics is a relatively young field of research, yet it is providing novel insights into gene regulation in the atherosclerotic arterial wall. That information is already pointing to new avenues for atherosclerosis (AS) prevention and therapy. In parallel, advances in nanoparticle (NP) technology allow effective targeting of drugs and bioactive molecules to the vascular wall. The partnership of NP technology and epigenetics in AS is just beginning and promises to produce novel exciting candidate treatments. Here, we briefly discuss the most relevant recent advances in the two fields. We focus on AS and DNA methylation, as the DNA methylome of that condition is better understood in comparison with the rest of the cardiovascular disease field. In particular, we review the most recent advances in NP-based delivery systems and their use for DNA methylome modification in inflammation. We also address the promises of DNA methyltransferase inhibitors for prevention and therapy. Furthermore, we emphasize the unique challenges in designing therapies that target the cardiovascular epigenome. Lastly, we touch the issue of human exposure to industrial NPs and its impact on the epigenome as a reminder of the undesired effects that any NP-based therapy must avoid to be apt for secondary prevention of AS.

Hyaluronic Acid Derived Hypoxia-Sensitive Nanocarrier for Tumor Targeted Drug Delivery

Hyaluronic acid (HA) is conjugated with BHQ3 moiety with azo bonds to prepare hypoxia-responsive polymer conjugate. Because of the amphiphilic nature, the polymer conjugate self-assembles to HA-BHQ3 nanoparticles (NPs). The anticancer drug doxorubicin (DOX) is loaded into the NPs. In the physiological environment, DOX is released slowly. In contrast, under hypoxic conditions, the azo bond in BHQ3 is cleaved, thus significantly enhancing the DOX release rate. For instance, after 24 h, 25% of DOX is released under normal conditions, while 74% of DOX is released under hypoxic conditions. In vitro cytotoxicity demonstrates higher toxicity in the hypoxic conditions. DOX@HA-BHQ3 NPs exhibit greater toxicity levels against 4T1 cells in hypoxic conditions. The fluorescent microscope images confirm the oxygen-dependent intracellular DOX release from the NPs. The in vivo biodistribution results suggest the tumor targetability of HA-BHQ3 NPs in 4T1 tumor-bearing mice.

Synergistic and receptor-mediated targeting of arthritic joints via intra-articular injectable smart hydrogels containing leflunomide-loaded lipid nanocarriers

Intra-articular drug delivery represents a tempting strategy for local treatment of rheumatoid arthritis. Targeting drugs to inflamed joints bypasses systemic-related side effects. Albeit, rapid drug clearance and short joint residence limit intra-articular administration. Herein, injectable smart hydrogels comprising free/nanoencapsulated leflunomide (LEF) were developed. Nanostructured lipid carriers (NLCs), 200-300 nm, were coated with either chondroitin sulfate (CHS), hyaluronic acid (HA), or chitosan (CS) to provide joint targetability. Coated NLCs were incorporated in either hyaluronic/pluronic (HP) or chitosan/β-glycerophosphate (CS/βGP) hydrogels. Optimized systems ensured convenient gelation time (14-100 s), injectability (5-15 s), formulation-dependent mechanical strength, and extended LEF release up to 51 days. In vivo intra-articular injection in induced arthritis rat model revealed that rats treated with HA-coated NLCs showed the fastest recovery. Histopathological examination demonstrated perfect joint healing in case of HA-coated LEF-NLCs in CS/βGP thermogel manifested as minor erosion of subchondral bone, improved intensity of extracellular matrix, cartilage thickness, and chondrocyte number. Both HA- and CHS-coated NLCs reduced TNF-α level 4-5-fold relative to positive control. The feat would be achieved via active targeting to CD44 receptors overexpressed in the articular tissue, limiting chondrocyte apoptosis together with innate synergistic targetability by promoting chondrocyte proliferation and neovascularization, inhibiting the production of pro-inflammatory cytokines, thus enhancing cartilaginous tissue repair.

Development of Lactoferrin-Loaded Liposomes for the Management of Dry Eye Disease and Ocular Inflammation

Dry eye disease (DED) is a high prevalent multifactorial disease characterized by a lack of homeostasis of the tear film which causes ocular surface inflammation, soreness, and visual disturbance. Conventional ophthalmic treatments present limitations such as low bioavailability and side effects. Lactoferrin (LF) constitutes a promising therapeutic tool, but its poor aqueous stability and high nasolacrimal duct drainage hinder its potential efficacy. In this study, we incorporate lactoferrin into hyaluronic acid coated liposomes by the lipid film method, followed by high pressure homogenization. Pharmacokinetic and pharmacodynamic profiles were evaluated in vitro and ex vivo. Cytotoxicity and ocular tolerance were assayed both in vitro and in vivo using New Zealand rabbits, as well as dry eye and anti-inflammatory treatments. LF loaded liposomes showed an average size of 90 nm, monomodal population, positive surface charge and a high molecular weight protein encapsulation of 53%. Biopharmaceutical behaviour was enhanced by the nanocarrier, and any cytotoxic effect was studied in human corneal epithelial cells. Developed liposomes revealed the ability to reverse dry eye symptoms and possess anti-inflammatory efficacy, without inducing ocular irritation. Hence, lactoferrin loaded liposomes could offer an innovative nanotechnological tool as suitable approach in the treatment of DED.

Recent Advances in ROS-Sensitive Nano-Formulations for Atherosclerosis Applications

Over the past decade, ROS-sensitive formulations have been widely used in atherosclerosis applications such as ROS scavenging, drug delivery, gene delivery, and imaging. The intensified interest in ROS-sensitive formulations is attributed to their unique self-adaptive properties, involving the main molecular mechanisms of solubility switch and degradation under the pathological ROS differences in atherosclerosis. This review outlines the advances in the use of ROS-sensitive formulations in atherosclerosis applications during the past decade, especially highlighting the general design requirements in relation to biomedical functional performance.

Hyaluronan/colistin polyelectrolyte complexes: Promising antiinfective drug delivery systems

Nanotechnology-based modification of known antimicrobial agents is a rational and straightforward way to improve their safety and effectiveness. The aim of this study was to develop colistin (CT)-loaded polymeric carriers based on hyaluronic acid (HA) for potential application as antimicrobial agents against multi-resistant gram-negative microorganisms (including ESKAPE pathogens). CT-containing particles were obtained via a polyelectrolyte interaction between protonated CT amino groups and HA carboxyl groups (the CT-HA complex formation constant [logK_CT-HA] was about 5.0). The resulting polyelectrolyte complexes had a size of 210-250 nm and a negative charge (ζ-potential -19 mV), with encapsulation and loading efficiencies of 100% and 20%, respectively. The developed CT delivery systems were characterized by modified release (45% and 85% of CT released in 15 and 60 min, respectively) compared to pure CT (100% CT released in 15 min). In vitro tests showed that the encapsulation of CT in polymer particles did not reduce its pharmacological activity; the minimum inhibitory concentrations of both encapsulated CT and pure CT were 1 μg/mL (against Pseudomonas aeruginosa).

Hyaluronic acid (HA)-coated naproxen-nanoparticles selectively target breast cancer stem cells through COX-independent pathways

Cytotoxic chemotherapy continues to be the main therapeutic option for patients with metastatic breast cancer. Several studies have reported a significant association between chronic inflammation, carcinogenesis and the presence of cancer stem cells (CSC). We hypothesized that the use of non-steroidal anti-inflammatory drugs targeted to the CSC population could help reducing tumor progression and dissemination in otherwise hard to treat metastatic breast cancer. Within this study cationic naproxen (NAP)-bearing polymeric nanoparticles (NPs) were obtained by self-assembly and they were coated with hyaluronic acid (HA) via electrostatic interaction. HA-coated and uncoated NAP-bearing NPs with different sizes were produced by changing the ionic strength of the aqueous preparation solutions (i.e. 300 and 350 nm or 100 and 130 nm in diameter, respectively). HA-NPs were fully characterized in terms of physicochemical parameters and biological response in cancer cells, macrophages and endothelial cells. Our results revealed that HA-coating of NPs provided a better control in NAP release and improved their hemocompatibility, while ensuring a strong CSC-targeting in MCF-7 breast cancer cells. Furthermore, the best polymeric NPs formulation significantly (p < 0.001) reduced MCF-7 cells viability when compared to free drug (i.e. 45 ± 6% for S-HA-NPs and 87 ± 10% for free NAP) by p53-dependent induction of apoptosis; and the migration of these cell line was also significantly (p < 0.01) reduced by the nano-formulated NAP (i.e. 76.4% of open wound for S-HA-NPs and 61.6% of open wound for NAP). This increased anti-cancer activity of HA-NAP-NPs might be related to the induction of apoptosis through alterations of the GSK-3β-related COX-independent pathway. Overall, these findings suggest that the HA-NAP-NPs have the potential to improve the treatment of advanced breast cancer by increasing the anti-proliferative effect of NAP within the CSC subpopulation.

Glycosaminoglycans: Carriers and Targets for Tailored Anti-Cancer Therapy

The tumor microenvironment (TME) is composed of cancerous, non-cancerous, stromal, and immune cells that are surrounded by the components of the extracellular matrix (ECM). Glycosaminoglycans (GAGs), natural biomacromolecules, essential ECM, and cell membrane components are extensively altered in cancer tissues. During disease progression, the GAG fine structure changes in a manner associated with disease evolution. Thus, changes in the GAG sulfation pattern are immediately correlated to malignant transformation. Their molecular weight, distribution, composition, and fine modifications, including sulfation, exhibit distinct alterations during cancer development. GAGs and GAG-based molecules, due to their unique properties, are suggested as promising effectors for anticancer therapy. Considering their participation in tumorigenesis, their utilization in drug development has been the focus of both industry and academic research efforts. These efforts have been developing in two main directions; (i) utilizing GAGs as targets of therapeutic strategies and (ii) employing GAGs specificity and excellent physicochemical properties for targeted delivery of cancer therapeutics. This review will comprehensively discuss recent developments and the broad potential of GAG utilization for cancer therapy.

Dual-Targeted Hyaluronic Acid/Albumin Micelle-Like Nanoparticles for the Vectorization of Doxorubicin

Drug targeting of tumor cells is one of the great challenges in cancer therapy; nanoparticles based on natural polymers represent valuable tools to achieve this aim. The ability to respond to environmental signals from the pathological site (e.g., altered redox potential), together with the specific interaction with membrane receptors overexpressed on cancer cells membrane (e.g., CD44 receptors), represent the main features of actively targeted nanoparticles. In this work, redox-responsive micelle-like nanoparticles were prepared by self-assembling of a hyaluronic acid–human serum albumin conjugate containing cystamine moieties acting as a functional spacer. The conjugation procedure consisted of a reductive amination step of hyaluronic acid followed by condensation with albumin. After self-assembling, nanoparticles with a mean size of 70 nm and able to be destabilized in reducing media were obtained. Doxorubicin-loaded nanoparticles modulated drug release rate in response to different redox conditions. Finally, the viability and uptake experiments on healthy (BALB-3T3) and metastatic cancer (MDA-MB-231) cells proved the potential applicability of the proposed system as a drug vector in cancer therapy.

Targeted Hybrid Nanocarriers as a System Enhancing the Skin Structure

The skin is constantly exposed to external and internal factors that disturb its function. In this work, two nanosystems-levan nanoparticles and a surfactin-stabilized nanoemulsion were preserved (tested for microbial growth) and characterized (size, polydispersity, Zeta potential, and stability). The nanosystems were introduced in the model formulations-cream, tonic, and gel, and confirmed by TEM. The analysis showed that nanoemulsion has a spherical morphology and size 220-300 nm, while levan nanoparticles had irregular shapes independently of the use of matrix and with particle size (130-260 nm). Additionally, we examined the antiradical effect of levan nanoparticles and nanoemulsion in the prototype of formulations by scavenging DPPH (2,2-diphenyl-1-picrylhydrazyl; EPR spectroscopy). The model cream with both nanosystems and the whole range of products with nanosystems were evaluated in vivo for hydration, elasticity, smoothness, wrinkles and vascular lesions, discoloration, respectively. The cream improved skin condition in all tested parameters in at least 50% of volunteers. The use of more comprehensive care, additionally consisting of a tonic and gel, reduced the previously existing skin discoloration to 10.42 ± 0.58%. The presented prototype formulations are promising in improving skin conditions.

Tumor Environment-Responsive Hyaluronan Conjugated Zinc Protoporphyrin for Targeted Anticancer Photodynamic Therapy

Targeted tumor accumulation, tumor environment responsive drug release, and effective internalization are critical issues being considered in developing anticancer nanomedicine. In this context, we synthesized a tumor environment-responsive nanoprobe for anticancer photodynamic therapy (PDT) that is a hyaluronan conjugated zinc protoporphyrin via an ester bond (HA-es-ZnPP), and we examined its anticancer PDT effect both in vitro and in vivo. HA-es-ZnPP exhibits high water-solubility and forms micelles of ~40 nm in aqueous solutions. HA-es-ZnPP shows fluorescence quenching without apparent 1O2 generation under light irradiation because of micelle formation. However, 1O2 was extensively generated when the micelle is disrupted, and ZnPP is released. Compared to native ZnPP, HA-es-ZnPP showed lower but comparable intracellular uptake and cytotoxicity in cultured mouse C26 colon cancer cells; more importantly, light irradiation resulted in 10-time increased cytotoxicity, which is the PDT effect. In a mouse sarcoma S180 solid tumor model, HA-es-ZnPP as polymeric micelles exhibited a prolonged systemic circulation time and the consequent tumor-selective accumulation based on the enhanced permeability and retention (EPR) effect was evidenced. Consequently, a remarkable anticancer PDT effect was achieved using HA-es-ZnPP and a xenon light source, without apparent side effects. These findings suggest the potential of HA-es-ZnPP as a candidate anticancer nanomedicine for PDT.

Understanding In Vivo Fate of Nucleic Acid and Gene Medicines for the Rational Design of Drugs

Nucleic acid and genetic medicines are increasingly being developed, owing to their potential to treat a variety of intractable diseases. A comprehensive understanding of the in vivo fate of these agents is vital for the rational design, discovery, and fast and straightforward development of the drugs. In case of intravascular administration of nucleic acids and genetic medicines, interaction with blood components, especially plasma proteins, is unavoidable. However, on the flip side, such interaction can be utilized wisely to manipulate the pharmacokinetics of the agents. In other words, plasma protein binding can help in suppressing the elimination of nucleic acids from the blood stream and deliver naked oligonucleotides and gene carriers into target cells. To control the distribution of these agents in the body, the ligand conjugation method is widely applied. It is also important to understand intracellular localization. In this context, endocytosis pathway, endosomal escape, and nuclear transport should be considered and discussed. Encapsulated nucleic acids and genes must be dissociated from the carriers to exert their activity. In this review, we summarize the in vivo fate of nucleic acid and gene medicines and provide guidelines for the rational design of drugs.

Polymer based nanoparticles for biomedical applications by microfluidic techniques: from design to biological evaluation

The development of microfluidic technologies represents a new strategy to produce and test drug delivery systems.

Polysaccharide nanoparticles: from fabrication to applications

The present review highlights the developments in polysaccharide nanoparticles with a particular focus on applications in biomedicine, cosmetics and food.

Effect of Hyaluronic Acid and Pluronic-F68 on the Surface Properties of Foam as a Delivery System for Polidocanol in Sclerotherapy

The use of foams to deliver bioactive agents and drugs is increasing in pharmaceutics. One example is the use of foam as a delivery system for polidocanol (POL) in sclerotherapy, with the addition of bioactive compounds to improve the delivery system being a current subject of study. This work shows the influence of two bioactive additives on the structure and stability of POL foam: hyaluronic acid (HA) and Pluronic-F68 (F68). HA is a natural non-surface-active biopolymer present in the extracellular matrix while F68 is a surface-active poloxamer that is biocompatible with plasma-derived fluids. Both additives increase the bulk viscosity of the sample, improving foam stability. However, HA doubled and F68 quadruplicated the foam half lifetime of POL. HA reduced the size and polydispersity of the bubble size distribution and increased the surface elasticity with respect to POL. Both facts have a positive impact in terms of foam stability. F68 also altered bubble structure and increased surface elasticity, again contributing to the enhancement of foam stability. The surface characterization of these systems is important, as in foam sclerotherapy it is crucial to assure the presence of POL at the surface of the bubbles in order to deliver the sclerosant agent in the target vein.