Immunostimulatory and antiangiogenic activities of low molecular weight hyaluronic acid

Marine polysaccharides: Biological activities and applications in drug delivery systems

The ocean is the common home of a large number of marine organisms, including plants, animals, and microorganisms. Researchers can extract thousands of important bioactive components from the oceans and use them extensively to treat and prevent diseases. In contrast, marine polysaccharide macromolecules such as alginate, carrageenan, Laminarin, fucoidan, chitosan, and hyaluronic acid have excellent physicochemical properties, good biocompatibility, and high bioactivity, which ensures their wide applications and strong therapeutic potentials in drug delivery. Drug delivery systems (DDS) based on marine polysaccharides and modified marine polysaccharide molecules have emerged as an innovative technology for controlling drug distribution on temporal, spatial, and dosage scales. They can detect and respond to external stimuli such as pH, temperature, and electric fields. These properties have led to their wide application in the design of novel drug delivery systems such as hydrogels, polymeric micelles, liposomes, microneedles, microspheres, etc. In addition, marine polysaccharide-based DDS not only have smart response properties but also can combine with the unique biological properties of the marine polysaccharide base to exert synergistic therapeutic effects. The biological activities of marine polysaccharides and the design of marine polysaccharide-based DDS are reviewed. Marine polysaccharide-based responsive DDS are expected to provide new strategies and solutions for disease treatment.

Lactiplantibacillus plantarum DLPT4 Protects Against Cyclophosphamide-Induced Immunosuppression in Mice by Regulating Immune Response and Intestinal Flora

In this study, the strain Lactiplantibacillus plantarum DLPT4 was investigated for the immunostimulatory activity in cyclophosphamide (CTX)-induced immunosuppressed BALB/c mice. L. plantarum DLPT4 was administered to BALB/c mice by oral gavage for 30 days, and CTX was injected intraperitoneally from the 25th to the 27th days. Intraperitoneal injection of CTX caused damage to the thymic cortex and intestines, and the immune dysfunction of the BALB/c mice. L. plantarum DLPT4 oral administration exerted immunoregulating effects evidenced by increasing serum immunoglobulin (IgA, IgG, and IgM) levels and reducing the genes expression of pro-inflammatory factors (IL-6, IL-1β, and TNF-α) of the CTX-induced immunosuppressed mice. The results of the metagenome-sequencing analysis showed that oral administration of L. plantarum DLPT4 could regulate the intestinal microbial community of the immunosuppressed mice by changing the ratio of Lactiplantibacillus and Bifidobacterium. Meanwhile, the abundance of carbohydrate enzyme (CAZyme), immune diseases metabolic pathways, and AP-1/MAPK signaling pathways were enriched in the mice administrated with L. plantarum DLPT4. In conclusion, oral administration of L. plantarum DLPT4 ameliorated symptoms of CTX-induced immunosuppressed mice by regulating gut microbiota, influencing the abundance of carbohydrate esterase in the intestinal flora, and enhancing immune metabolic activity. L. plantarum DLPT4 could be a potential probiotic to regulate the immune response.

Effect of orodispersible hyaluronic acid film on palatal mucosa wound healing

OBJECTIVE

The objective of the study was to evaluate the healing effect of hyaluronic acid films on palatal wounds.

MATERIALS AND METHODS

After making 5-mm diameter palatal wounds, 72 rats were randomly assigned to three groups: control, hyaluronic acid gel, and hyaluronic acid film. The animals were sacrificed at 3, 7, and 21 days after the experiment. Clinical, histological, and RT-PCR analyses were performed. Human ex vivo oral mucosa models were used. Histological analysis and pan-cytokeratin staining were performed at 5 days after wound creation.

RESULTS

In rat model, both gels and films showed favorable healing on Days 3 and 7 compared with healing in the control (p < 0.05). Film showed remarkable VEGF and α-SMA expression than did the others (p < 0.05). Immunohistochemical analysis showed that film exhibited significantly lower CD68 and greater α-SMA and vimentin expression levels than those in the others (p < 0.05). In human model, re-epithelialization rate of film group was significantly higher than that of the others. Complete epithelial regeneration was confirmed only in film group using pan-cytokeratin staining.

CONCLUSIONS

Within the limits of this study, hyaluronic acid film outperformed gels in terms of palatal wound healing in both models.

In Vitro Fermentation of Hyaluronan with Different Molecular Weights by Human Gut Microbiota: Differential Effects on Gut Microbiota Structure and Metabolic Function

Hyaluronan (HA) has various biological functions and is used extensively as a dietary supplement. Previous studies have shown that the probiotic effects of polysaccharides are closely associated with their molecular properties. The intestinal microbiota has been demonstrated to degrade HA; however, the regulatory effects of different molecular weights (MW) of HA on gut microbiota and metabolites are unknown. In the present study, we performed in vitro fermentation of human-derived feces for three MWs of HA (HA1, 32.3 kDa; HA2, 411 kDa; and HA3, 1510 kDa) to investigate the differences in the fermentation properties of HA with different MWs. We found that gut microbiota can utilize all HAs and, consequently, produce large amounts of short-chain fatty acids (SCFAs). In addition, we showed that all three HA MWs promoted the growth of Bacteroides, Parabacteroides, and Faecalibacterium, with HA1 being more effective at promoting the growth of Bacteroides. HAs have various regulatory effects on the structure and metabolites of the gut microbiota. Spearman's correlation analysis revealed that alterations in gut microbiota and their metabolites were significantly correlated with changes in metabolic markers. For instance, HA1 enriched α-eleostearic acid and DL-3-aminoisobutyric acid by regulating the abundance of Bacteroides, and HA3 enriched Thymidin by regulating Faecalibacterium. Collectively, the fermentation properties of HA vary across MW, and our results provide insights into the potential association between the MW of HA and its fermentation characteristics by the gut microbiota. These findings provide insights into the influence of the gut microbiota and HAs on the health of the host.

Comprehensive review on biosynthesis of hyaluronic acid with different molecular weights and its biomedical applications

Hyaluronic acid (HA), an anionic and nonsulfated glycosaminoglycan, is the main structural component of various tissues and plays an important role in various biological processes. Given the promising properties of HA, such as high cellular compatibility, moisture retention, antiaging, proper interaction with cells, and CD44 targeting, HA can be widely used extensively in drug delivery, tissue engineering, wound healing, and cancer therapy. HA can obtain from animal tissues and microbial fermentation, but its applications depend on its molecular weight. Microbial fermentation is a common method for HA production on an industrial scale and S. zooepidemicus is the most frequently used strain in HA production. Culture conditions including pH, temperature, agitation rate, aeration speed, shear stress, dissolved oxygen, and bioreactor type significantly affect HA biosynthesis properties. In this review all the HA production methods and purification techniques to improve its physicochemical and biological properties for various biomedical applications are discussed in details. In addition, we showed that how HA molecular weight can significantly affect its properties and applications.

Mediation of synergistic chemotherapy and gene therapy via nanoparticles based on chitosan and ionic polysaccharides

Nanoparticles (NPs)-based on various ionic polysaccharides, including chitosan, hyaluronic acid, and alginate have been frequently summarized for controlled release applications, however, most of the published reviews, to our knowledge, focused on the delivery of a single therapeutic agent. A comprehensive summarization of the co-delivery of multiple therapeutic agents by the ionic polysaccharides-based NPs, especially on the optimization of the polysaccharide structure for overcoming various extracellular and intracellular barriers toward maximized synergistic effects, to our knowledge, has been rarely explored so far. For this purpose, the strategies used for overcoming various extracellular and intracellular barriers in vivo were introduced first to provide guidance for the rational design of ionic polysaccharides-based NPs with desired features, including long-term circulation, enhanced cellular internalization, controllable drug/gene release, endosomal escape and improved nucleus localization. Next, four preparation strategies were summarized including three physical methods of polyelectrolyte complexation, ionic crosslinking, and self-assembly and a chemical conjugation approach. The challenges and future trends of this rapidly developing field were finally discussed in the concluding remarks. The important guidelines on the rational design of ionic polysaccharides-based NPs for maximized synergistic efficiency drawn in this review will promote the future generation and clinical translation of polysaccharides-based NPs for cancer therapy.

Biochemical and Molecular Characteristics of a Novel Hyaluronic Acid Lyase from Citrobacter freundii

The Gram-negative strain of Citrobacter freundii, YNLX, has the ability to degrade hyaluronic acid. In this study, we expressed a C. freundii hyaluronic acid lyase, from polysaccharide lyase family 8, in Escherichia coli. The purified recombinant enzyme (rHynACF8) showed a substantially higher cleavage activity of hyaluronic acid than chondroitin sulfate. We found that its optimal pH and temperature are 5.5 and 35 °C, respectively. In addition, the enzyme activity was not notably affected by most metal ions. Km and kcat of rHynACF8 towards HA were 1.5 ± 0.01 mg/mL and 30.9 ± 0.5 /s, respectively. rHynACF8 is an endo-acting enzyme. Its cleavage products had dramatically increased antioxidant activity than hyaluronic acid in vitro (p < 0.001). As the molecular weight of hyaluronic acid decreased, the intramolecular interactions among antioxidant functional groups were removed; in the process of the cracking reaction, new double bonds formed and conjugated with the carbonyl group. We presumed that the structural change is the critical factor influencing antioxidant capacity. Overall, we found that rHynACF8 from Gram-negative bacteria with metal ion resistance, indicated the relationship between the function and structure of its antioxidant cleavage product.

Orodispersible hyaluronic acid film delivery for oral wound healing in rats

Background/purpose

Oral wound healing undergoes a dynamic process of oral environment. This study aimed to investigate the effects of hyaluronic acid (HA) film on oral wound healing in a rat model.

Materials and methods

A total of 60 rats with tongue wounds (5 mm in diameter) were randomly divided into control (n = 20), HA gel (n = 20), and HA film groups (n = 20). The animals were sacrificed on either 3 or 7 days after the experiment. Clinical, histological, and quantitative reverse transcriptase-polymerase chain reaction analysis were performed to evaluate the healing rate, inflammation, re-epithelialization, and gene expression of wound healing biomarkers.

Results

The healing rates of HA gel (84.4 ± 9.2%) and HA film (74.0 ± 15.0%) were significantly higher than that of the control (51.7 ± 16.9%) on day 7 (P < 0.001 and P = 0.002, respectively). Histological analysis revealed no significant differences between the groups on day 3. On day 7, only the HA film showed significant improvement in inflammation (P = 0.038) and re-epithelialization (P = 0.011) compared to the control. Regarding wound healing biomarkers, both HA gel and HA film groups showed lower level of COL1α1 expression on day 3 compared to the control.

Conclusion

Within the limits of this study, HA film was found to be effective for oral wound healing, particularly for re-epithelialization. This finding suggests that HA film delivery can be beneficial not only for clinical convenience but also for promoting oral wound healing.

Current advances in the biosynthesis of hyaluronic acid with variable molecular weights

Hyaluronic acid (HA) is a naturally formed acidic mucopolysaccharide, with excellent moisturising properties and used widely in the medicine, cosmetics, and food industries. The industrial production of specific molecular weight HA has become imperative. Different biological activities and physiological functions of HA mainly depend on the degree of polymerisation. This article reviews the research status and development prospects of the green biosynthesis and molecular weight regulation of HA. There is an application-based prerequisite of specific molecular weight of HA that could be regulated either during the fermentation process or via a controlled HA degradation process. This work provides an important theoretical basis for the downstream efficient production of diversified HA, which will further accelerate the research applications of HA and provide a good scientific basis and method reference for the study of the molecular weight regulation of similar biopolymers.

Enhancement of T2* Weighted MRI Imaging Sensitivity of U87MG Glioblastoma Cells Using γ-Ray Irradiated Low Molecular Weight Hyaluronic Acid-Conjugated Iron Nanoparticles

INTRODUCTION

It has been reported that low-molecular-weight hyaluronic acid (LMWHA) exhibits a potentially beneficial effect on cancer therapy through targeting of CD44 receptors on tumor cell surfaces. However, its applicability towards tumor detection is still unclear. In this regard, LMWHA-conjugated iron (Fe3O4) nanoparticles (LMWHA-IONPs) were prepared in order to evaluate its application for enhancing the T2* weighted MRI imaging sensitivity for tumor detection.

METHODS

LMWHA and Fe3O4 NPs were produced using γ-ray irradiation and chemical co-precipitation methods, respectively. First, LMWHA-conjugated FITC was prepared to confirm the ability of LMWHA to target U87MG cells using fluorescence microscopy. The hydrodynamic size distribution and dispersion of the IONPs and prepared LMWHA-IONPs were analyzed using dynamic light scattering (DLS). In addition, cell viability assays were performed to examine the biocompatibility of LMWHA and LMWHA-IONPs toward U87MG human glioblastoma and NIH3T3 fibroblast cell lines. The ability of LMWHA-IONPs to target tumor cells was confirmed by detecting iron (Fe) ion content using the thiocyanate method. Finally, time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging and in vitro magnetic resonance imaging (MRI) were performed to confirm the contrast enhancement effect of LMWHA-IONPs.

RESULTS

Florescence analysis results showed that LMWHA-FITC successfully targeted the surfaces of both tested cell types. The ability of LMWHA to target U87MG cells was higher than for NIH3T3 cells. Cell viability experiments showed that the fabricated LMWHA-IONPs possessed good biocompatibility for both cell lines. After co-culturing test cells with the LMWHA-IONPs, detected Fe ion content in the U87MG cells was much higher than that of the NIH3T3 cells in both thiocyanate assays and TOF-SIMs images. Finally, the addition of LMWHA-IONPs to the U87MG cells resulted in an obvious improvement in T2* weighted MR image contrast compared to control NIH3T3 cells.

DISCUSSION

Overall, the present results suggest that LMWHA-IONPs fabricated in this study provide an effective MRI contrast agent for improving the diagnosis of early stage glioblastoma in MRI examinations.

Polysaccharide Nanoparticles Can Efficiently Modulate the Immune Response against an HIV Peptide Antigen

The development of an effective HIV vaccine continues to be a major health challenge since, so far, only the RV144 trial has demonstrated a modest clinical efficacy. Recently, the targeting of the 12 highly conserved protease cleavage sites (PCS1-12) has been presented as a strategy seeking to hamper the maturation and infectivity of HIV. To pursue this line of research, and because peptide antigens have low immunogenicity, we have included these peptides in engineered nanoparticles, aiming at overcoming this limitation. More specifically, we investigated whether the covalent attachment of a PCS peptide (PCS5) to polysaccharide-based nanoparticles, and their coadministration with polyinosinic:polycytidylic acid (poly(I:C)), improved the generated immune response. To this end, PCS5 was first conjugated to two different polysaccharides (chitosan and hyaluronic acid) through either a stable or a cleavable bond and then associated with an oppositely charged polymer (dextran sulfate and chitosan) and poly(I:C) to form the nanoparticles. Nanoparticles associating PCS5 by ionic interactions were used in this study as the control formulation. In vivo, all nanosystems elicited high anti-PCS5 antibodies. Nanoparticles containing PCS5 conjugated and poly(I:C) seemed to induce the strongest activation of antigen-presenting cells. Interestingly, T cell activation presented different kinetics depending on the prototype. These findings show that both the nanoparticle composition and the conjugation of the HIV peptide antigen may play an important role in the generation of humoral and cellular responses.

Immunostimulatory activity of low-molecular-weight hyaluronan on dendritic cells stimulated with Aggregatibacter actinomycetemcomitans or Porphyromonas gingivalis

OBJECTIVES

Periodontitis is a chronic inflammatory disease characterized by tooth-supporting tissue destruction, which is elicited by the host's immune response triggered against periodonto-pathogen bacteria. During periodontal tissue destruction, extracellular matrix components are metabolized and fragmented. Some extracellular matrix component-derived fragments, such as low-molecular-weight hyaluronan (LMW-HA), have potent immunogenic potential, playing a role as damage-associated molecular patterns (DAMPs) during activation of immune cells. Dendritic cells (DCs) play a central role in the host's immune response displayed during periodontitis; thus, this study aimed to analyze whether LMW-HA has an immunostimulatory activity on DCs when stimulated with periodonto-pathogen bacteria.

MATERIALS AND METHODS

LMW-HA-treated and non-treated DCs were stimulated with Aggregatibacter actinomycetemcomitans or Porphyromonas gingivalis and the mRNA expression for cytokines tumor necrosis factor-α (TNF-alpha), interleukin-1β (IL-1B), interleukin-6 (IL-6), and interleukin-23 (IL-23A) was quantified by RT-qPCR. In addition, transcription factors interferon regulatory factor 4 (IRF4), interferon regulatory factor 8 (IRF8), neurogenic locus notch homolog protein 2 (NOTCH2), and basic leucine zipper ATF-like transcription factor 3 (BATF3), involved in DC activation, were analyzed.

RESULTS

Higher expression levels of TNF-alpha, IL-1B, IL-6, and IL-23A were detected in LMW-HA-treated DCs after bacterial infection, as compared with non-treated DCs. When LMW-HA-treated DCs were infected with A. actinomycetemcomitans, higher levels of IRF4, NOTCH2, and BATF3 were detected compared with non-treated cells; whereas against P. gingivalis infection, increased levels of IRF4 and NOTCH2 were detected.

CONCLUSION

LMW-HA plays an immunostimulatory role on the immune response triggered by DCs during infection with A. actinomycetemcomitans or P. gingivalis.

CLINICAL RELEVANCE

Detection of extracellular matrix component-derived fragments produced during periodontal tissue destruction, such as LMW-HA, could explain at least partly unsuccessful periodontal treatment and the chronicity of the disease.

Tau Pathology Promotes the Reorganization of the Extracellular Matrix and Inhibits the Formation of Perineuronal Nets by Regulating the Expression and the Distribution of Hyaluronic Acid Synthases

Hyaluronic acid (HA) is the backbone of the extracellular matrix (ECM) and provides biochemical and physical support to aggrecan-based perineuronal nets (PNNs), which are associated with the selective vulnerability of neurons in Alzheimer's disease (AD). Here, we showed that HA synthases (HASs), including Has1, Has2, and Has3, were widely expressed in murine central nervous system. All types of HASs were localized to cell bodies of neurons; only Has1 existed in the membranes of neural axons. By using TauP301S transgenic (Tg) mouse model, we found that the axonal-localization of Has1 was abolished in TauP301S overexpressed mouse brain, and the redistribution of Has1 was also observed in human AD brains, suggesting that the localization of Has1 is dependent on intact microtubules which are regulated partially by the phosphorylation and dephosphorylation cycles of tau proteins. Furthermore, Has1 was reduced and Has3 was increased in TauP301S Tg mouse brain, resulting in the upregulation of shorter-chain HA in the ECM. These findings suggest that by abolishing the axonal-localization of Has1 and promoting the expression of Has3 and the synthesis of shorter-chain HA, the tau pathology breaks the balance of ECM components, promotes the reorganization of the ECM, and inhibits the formation of PNNs in the hippocampus, and then regulates neuronal plasticity during the progression of AD.

Modulating the immune system through nanotechnology

Nowadays, nanotechnology-based modulation of the immune system is presented as a cutting-edge strategy, which may lead to significant improvements in the treatment of severe diseases. In particular, efforts have been focused on the development of nanotechnology-based vaccines, which could be used for immunization or generation of tolerance. In this review, we highlight how different immune responses can be elicited by tuning nanosystems properties. In addition, we discuss specific formulation approaches designed for the development of anti-infectious and anti-autoimmune vaccines, as well as those intended to prevent the formation of antibodies against biologicals.

Co-encapsulation of curcumin and resveratrol into novel nutraceutical hyalurosomes nano-food delivery system based on oligo-hyaluronic acid-curcumin polymer

In this work, in order to enhance the stability, bioavailability and antioxidant activity of insoluble antioxidants used into juice, yoghourt and nutritional supplements, the oligo-hyalurosomes nano-delivery system (CRHs) based on oligo-hyaluronic acid -curcumin (oHC) polymer loaded curcumin(Cur) and resveratrol (Res) was fabricated with new nanotechnolgy. The rosy biodegradable amphiphilic oHC polymer was successfully synthesized and used to fabricate the hyalurosomes containing both Cur and Res, called CRHs. The CRHs can spontaneously self-assemble into nano-sized spherical shape of average particle size 134.5±5.1nm and Zeta potential -29.4±1.2 at pH 7.4 PBS conditions. In vitro gastrointestinal release test showed a perfect stability and outstanding sustained release character. Moreover, compared to the single formulations and liposomes, CRHs showed a dose-dependent manner with a higher radical scavenging activity. Therefore, the novel CRHs nano-food manifested the hopeful properties for the new effective gastrointestinal formulation and promising new nano-food delivery system in the use of juice, yoghourt and nutritional supplements.

Absence of differences among low, middle, and high molecular weight hyaluronan in activating murine immune cells in vitro

Hyaluronan (HA) effects on immune response are suggested to be dependent on HA molecular weight (MW), as low MW HA should activate immune cells in contrast to high MW HA. However, some current studies do not support this conception and emphasize the importance of the form of preparation of HA, particularly with respect to its purity and origin. We compared the activation of mouse immune cells by HA samples (100kDa, 500kDa, and 997kDa) prepared from HA originating from rooster comb, and HA samples (71kDa, 500kDa, and 1000kDa) prepared from pharmacological grade HA originating from Streptococcus equi. Interestingly, in contrast to established theory, only middle and high MW HA originating from rooster comb induced the production of tumor necrosis factor-α by macrophages and in whole blood. Further, all tested preparations of HA failed to induce the expression of inducible nitric oxide synthase, the production of nitric oxide, or the expression of cyclooxygenase 2 in macrophages and splenocytes. Importantly, all HA samples originating from rooster comb were found to be contaminated by endotoxin (up to 1.23EU/ml). Hence, low MW HA did not reveal itself to have significantly higher immunostimulatory activity compared to HA of higher MW.

Hyaluronic Acid and Its Derivatives in Coating and Delivery Systems: Applications in Tissue Engineering, Regenerative Medicine and Immunomodulation

As an Extracellular Matrix (ECM) component, Hyaluronic acid (HA) plays a multi-faceted role in cell migration, proliferation and differentiation at micro level and system level events such as tissue water homeostasis. Among its biological functions, it is known to interact with cytokines and contribute to their retention in ECM microenvironment. In addition to its biological functions, it has advantageous physical properties which result in the industrial endeavors in the synthesis and extraction of HA for variety of applications ranging from medical to cosmetic. Recently, HA and its derivatives have been the focus of active research for applications in biomedical device coatings, drug delivery systems and in the form of scaffolds or cell-laden hydrogels for tissue engineering. A specific reason for the increase in use of HA based structures is their immunomodulatory and regeneration inducing capacities. In this context, this article reviews recent literature on modulation of the implantable biomaterial microenvironment by systems based on HA and its derivatives, particularly hydrogels and microscale coatings that are able to deliver cytokines in order to reduce the adverse immune reactions and promote tissue healing.

Is molecular size a discriminating factor in hyaluronan interaction with human cells?

Nowadays there is a great interest in investigating the effect of particular hyaluronan fragments in the biomedical field and in cosmeceutical applications. Literature has reported that very low molecular weight HA (Mw<5kDa) has an inflammatory effect, whilst HA ranging from 15 to 250 has shown controversial effects. This work aims to give better elucidation on the correlation between the different sized HA fragments and their biological functions. In this respect, a simple and effective degradation strategy is used to obtain several HA fragments. Also, an hydrodynamic and structural characterization was performed in order to obtain samples suitable to evaluate cellular response. In particular an in vitro scratch test in time lapse experiments was used to study the effect of HA fragments, ranging from 1800 to 6kDa on wound dermal reparation based on human keratinocytes. All high and low Mw HA used in this study allowed for faster wound closure compared to the un-treated cells, except for 6kDa that, on the contrary, prevented repair. In addition, TGF-β 1, TNFα and IL-6, representative biomarkers of the inflammation phase occurring in wound healing process, were quantified by RT-PCR. A general up-regulation trend of these biomarkers was found with the HA molecular weight reduction. LHA6kDa was the only treatment that induced a major inflammatory response (over 30 fold increase respect to control) confirming the recent literature outcomes. IL-6 protein level evaluated through ELISA assay corroborated the previous results. Furthermore, activation of key HA receptors, such as CD44, RHAMM, TLR4, with respect to hyaluronan size, was evaluated, at transcriptional level showing selective recognition by HA 1800, 1400, 500 for CD44, whilst the lower Mw fragments activated TLR-4 moderately at 50 and 15kDa. An increase to "alarm" level was found for 6kDa fragments. Immunofluorescence staining confirmed this data. The present research work demonstrated that the diverse pharma grade hyaluronan fragments could modulate cellular processes differently. From 1800kDa down to 50kDa, CD44 was the recognized receptor and pro-inflammatory biomarkers were only slightly up-regulated during wound healing in the presence of HA. Finally our outcomes showed that the lower the fragment size the higher the concern for inflammatory cytokines up-regulation; repair process impairment was highlighted only for 6kDa chains.

Targeting cancer with hyaluronic acid-based nanocarriers: recent advances and translational perspectives

Hyaluronic acid is a natural polysaccharide that has been widely explored for the development of anticancer therapies due to its ability to target cancer cells. Moreover, advances made in the last decade have revealed the versatility of this biomaterial in the design of multifunctional carriers, intended for the delivery of a variety of bioactive molecules, including polynucleotides, immunomodulatory drugs and imaging agents. In this review, we aim to provide an overview of the major recent achievements in this field, highlighting the application of the newly developed nanostructures in combination therapies, immunomodulation and theranostics. Finally, we will discuss the main challenges and technological advances that will allow these carriers to be considered as candidates for clinical development.

Toll-like receptor 4-related immunostimulatory polysaccharides: Primary structure, activity relationships, and possible interaction models

Toll-like receptor (TLR) 4 is an important polysaccharide receptor; however, the relationships between the structures and biological activities of TLR4 and polysaccharides remain unknown. Many recent findings have revealed the primary structure of TLR4/MD-2-related polysaccharides, and several three-dimensional structure models of polysaccharide-binding proteins have been reported; and these models provide insights into the mechanisms through which polysaccharides interact with TLR4. In this review, we first discuss the origins of polysaccharides related to TLR4, including polysaccharides from higher plants, fungi, bacteria, algae, and animals. We then briefly describe the glucosidic bond types of TLR4-related heteroglycans and homoglycans and describe the typical molecular weights of TLR4-related polysaccharides. The primary structures and activity relationships of polysaccharides with TLR4/MD-2 are also discussed. Finally, based on the existing interaction models of LPS with TLR4/MD-2 and linear polysaccharides with proteins, we provide insights into the possible interaction models of polysaccharide ligands with TLR4/MD-2. To our knowledge, this review is the first to summarize the primary structures and activity relationships of TLR4-related polysaccharides and the possible mechanisms of interaction for TLR4 and TLR4-related polysaccharides.

Structure-function relationships of immunostimulatory polysaccharides: A review

Immunostimulatory polysaccharides are compounds capable of interacting with the immune system and enhance specific mechanisms of the host response. Glucans, mannans, pectic polysaccharides, arabinogalactans, fucoidans, galactans, hyaluronans, fructans, and xylans are polysaccharides with reported immunostimulatory activity. The structural features that have been related with such activity are the monosaccharide and glycosidic-linkage composition, conformation, molecular weight, functional groups, and branching characteristics. However, the establishment of structure-function relationships is possible only if purified and characterized polysaccharides are used and selective structural modifications performed. Aiming at contributing to the definition of the structure-function relationships necessary to design immunostimulatory polysaccharides with potential for preventive or therapeutical purposes or to be recognized as health-improving ingredients in functional foods, this review introduces basic immunological concepts required to understand the mechanisms that rule the potential claimed immunostimulatory activity of polysaccharides and critically presents a literature survey on the structural features of the polysaccharides and reported immunostimulatory activity.

Structural elucidation of a polysaccharide from Chrysanthemum morifolium flowers with anti-angiogenic activity

The flowers of Chrysanthemum morifolium were extracted with 5% sodium hydroxide, yielding a neutral polysaccharide (JHB0S2) with a molecular weight of 16 kDa by anion-exchange chromatography on a DEAE-cellulose column and gel permeation chromatography on a Sephacryl S-200 HR column. JHB0S2 was found to contain glucose, xylose, arabinose and galactose in molar ratio of 2.9:2.3:1.0:1.2. Through the linkage analysis, partial acid hydrolysis and NMR spectra and so forth, indicated that its backbone consisted of 1,4-linked β-Glcp, nearly 50% of which was substituted at O-6 by 1,2-linked α-Xylp terminated with Galp or Xylp. Furthermore, some of 1,2-linked α-Xylp was substituted at O-4 by α-Araf-(1→5)-α-Araf-(1→6)-β-Galp. The biological test showed that JHB0S2 could inhibit the tube formation of HMEC-1 cells.

Hyaluronan - a functional and structural sweet spot in the tissue microenvironment

Transition from homeostatic to reactive matrix remodeling is a fundamental adaptive tissue response to injury, inflammatory disease, fibrosis, and cancer. Alterations in architecture, physical properties, and matrix composition result in changes in biomechanical and biochemical cellular signaling. The dynamics of pericellular and extracellular matrices, including matrix protein, proteoglycan, and glycosaminoglycan modification are continually emerging as essential regulatory mechanisms underlying cellular and tissue function. Nevertheless, the impact of matrix organization on inflammation and immunity in particular and the consequent effects on tissue healing and disease outcome are arguably under-studied aspects of adaptive stress responses. Herein, we review how the predominant glycosaminoglycan hyaluronan (HA) contributes to the structure and function of the tissue microenvironment. Specifically, we examine the evidence of HA degradation and the generation of biologically active smaller HA fragments in pathological settings in vivo. We discuss how HA fragments versus nascent HA via alternate receptor-mediated signaling influence inflammatory cell recruitment and differentiation, resident cell activation, as well as tumor growth, survival, and metastasis. Finally, we discuss how HA fragmentation impacts restoration of normal tissue function and pathological outcomes in disease.

Effects of Hyriopsis cumingii polysaccharides on angiogenesis, macrophage chemotaxis, proliferation and phagocytosis

Hyriopsis cumingii polysaccharides (HCPS) showed anti-angiogenic activity and promoting effects on the chemotaxis, proliferation and phagocytosis of peritoneal macrophage.

Beneficial effects of hyaluronic acid

Biomaterials are playing a vital role in our day-to-day life. Hyaluronan (hyaluronic acid), a biomaterial, receives special attention among them. Hyaluronic acid (HA) is a polyanionic natural polymer occurring as linear polysaccharide composed of glucuronic acid and N-acetylglucosamine repeats via a β-1,4 linkage. It is the most versatile macromolecule present in the connective tissues of all vertebrates. Hyaluronic acid has a wide range of applications with its excellent physicochemical properties such as biodegradability, biocompatibility, nontoxicity, and nonimmunogenicity and serves as an excellent tool in biomedical applications such as osteoarthritis surgery, ocular surgery, plastic surgery, tissue engineering, and drug delivery. It plays a key role in cushioning and lubricating the body and is abundant in the eyes, joints, and heart valves. A powerful antioxidant, hyaluronic acid is perhaps best known for its ability to bond water to tissue. Hyaluronan production increases in proliferating cells, and the polymer may play a role in mitosis. This chapter gives an overview of hyaluronic acid and its physicochemical properties and applications. This chapter gives a deep understanding on the special benefits of hyaluronic acid in the fields of pharmaceutical, medical, and environmental applications. Hyaluronic acid paves the way for beneficial research and applications to the welfare of life forms.