Advanced Wound Healing and Scar Reduction Using an Innovative Anti-ROS Polysaccharide Hydrogel with Recombinant Human Collagen Type III.

Excessive fibrotic scar formation during skin defect repair poses a formidable challenge, impeding the simultaneous acceleration of wound healing and prevention of scar formation and hindering the restoration of skin integrity and functionality. Drawing inspiration from the structural, compositional, and biological attributes of skin, we developed a hydrogel containing modified recombinant human collagen type III and thiolated hyaluronic acid to address the challenges of regenerating skin appendages and improving the recovery of skin functions after injury by reducing fibrotic scarring. The hydrogel displayed favorable biocompatibility, antioxidant properties, angiogenic potential, and fibroblast migration stimulation in vitro. In a rat full-layer defect model, it reduced inflammation, promoted microvascular formation, and significantly enhanced the wound healing speed and effectiveness. Additionally, by upregulating fibrosis-associated genes, such as TGFB1, it facilitated collagen accumulation and a beneficial balance between type I and type III collagen, potentially expediting skin regeneration and functional recovery. In conclusion, the utilization of rhCol III-HS demonstrated considerable potential as a wound dressing, offering a highly effective strategy for the restoration and rejuvenation of complete skin defects.

Mucoadhesive Thiolated Hyaluronic Acid/Pluronic F127 Nanogel Formation via Thiol-Maleimide Click Reaction for Intravesical Drug Delivery.

The development of nanocarriers to prolong the residence time and enhance the permeability of chemotherapeutic drugs on bladder mucosa is important in the postsurgery treatment of superficial bladder cancers (BCs). Here, the mucoadhesive HA-SH/PF127 nanogels composed of a temperature-sensitive Pluronic F127 (PF127) core and thiolated hyaluronic acid (HA-SH) shell were prepared by the emulsification/solvent evaporation method. The nanogels were constructed through the thiol-maleimide click reaction in the HA-SH aqueous side of the oil-water interface and self-oxidized cross-linking thiols between HA-SH. The HA-SH/PF127 nanogels prepared at different thiol-to-maleimide group molar ratios, water-to-oil volume ratios, and cross-linking reaction times were characterized regarding hydrodynamic diameter (Dh) and zeta potential (ζ), and the optimal formulation was obtained. The excellent mucoadhesive properties of the HA-SH/PF127 nanogels were evaluated by using the mucin particle method. Doxorubicin (DOX) was encapsulated in the PF127 core of DOX@HA-SH/PF127 nanogels with a high loading efficiency (87.5%) and sustained release from the nanogels in artificial urine. Ex vivo studies on porcine bladder mucosa showed that the DOX@HA-SH/PF127 nanogels enhanced the penetration of the DOX into the bladder mucosa without disrupting the mucus structure or the bladder tissue. A significant dose-dependent cytotoxic effect of DOX@HA-SH/PF127 nanogels on both T24 and MB49 cells was observed. The present study demonstrates that the mucoadhesive HA-SH/PF127 nanogels are a promising intravesical drug delivery system for superficial BC therapy.

pH-sensitive docetaxel-loaded chitosan/thiolated hyaluronic acid polymeric nanoparticles for colorectal cancer.

Aim: This study aimed to develop and evaluate pH-sensitive docetaxel-loaded thiolated hyaluronic acid (HA-SH) nanoparticles (NPs) for targeted treatment of colon cancer. Materials & methods: HA-SH, synthesized via oxidation and subsequent covalent linkage to cysteamine, served as the precursor for developing HA-SH NPs through polyelectrolyte complexation involving chitosan and thiol-bearing HA. Results & conclusion: HA-SH NPs displayed favorable characteristics, with small particle sizes (184-270 nm), positive zeta potential (15.4-18.6 mV) and high entrapment efficiency (91.66-95.02%). In vitro, NPs demonstrated potent mucoadhesion and enhanced cytotoxicity compared with free docetaxel. In vivo assessments confirmed safety and biocompatibility, suggesting HA-SH NPs as promising pH-sensitive drug carriers with enhanced antitumor activity for colorectal cancer treatments.

Mucoadhesive and thermosensitive Bletilla striata polysaccharide/chitosan hydrogel loaded nanoparticles for rectal drug delivery in ulcerative colitis.

Ulcerative colitis (UC) is a chronic disease with diffuse mucosal inflammation limited to the colon. A topical drug delivery system that could be facilely performed and efficiently retained at colon are attractive for clinical ulcerative colitis treatment. Herein, a novel platform for rectal administration of thermosensitive hydrogel co-loaded with nanoparticles to treat ulcerative colitis was developed. Thiolated-hyaluronic acid was synthesized, and prepared nanoparticles with zein and Puerarin. And the Bletilla striata polysaccharide with colonic mucosa repair effect was oxidized, and mixed with chitosan and ß-sodium glycerophosphate to prepare thermosensitive hydrogel. Thermosensitive hydrogels were combined with nanoparticles to investigate their mucosal adhesion, retention, and permeability, as well as their therapeutic effects on ulcerative colitis. Thiolated-hyaluronic acid nanoparticles had good stability, and could be quickly converted into hydrogel at body temperature when combined with thermosensitive hydrogel. The nanoparticles-loaded thermosensitive hydrogel also was excellent at mucosal penetration, enhancing the retention time of drugs in colon, and effectively controlling drug release. In vivo ulcerative colitis treatment revealed that the nanoparticles-loaded hydrogel significantly repaired the colonic mucosa and inhibit colonic inflammation. Therefore, the thermosensitive hydrogel co-loaded nanoparticles will have a promising application in effective treatment of ulcerative colitis by topical administration.

Thiolated hyaluronic acid and catalase-enhanced CD44-targeting and oxygen self-supplying nanoplatforms with photothermal/photodynamic effects against hypoxic breast cancer cells.

Photothermal and photodynamic therapies (PTT/PDT) have been widely accepted as noninvasive therapeutic methods for cancer treatment. However, tumor hypoxia and insufficient delivery of photoactive compounds to cancer cells can reduce the efficacy of phototherapy. Herein, we first synthesized thiolated hyaluronic acid (THA) and then conjugated it with catalase (CAT) onto chlorin e6 (Ce6)-adsorbed small gold nanorods (Ce6@sAuNRs) with near-infrared (NIR)/visible light activated photothermal/photodynamic effects. The conjugation of THA and CAT on Ce6@sAuNRs resulted in a red-shift of the longitudinal LSPR absorption band of sAuNRs up to 1000 nm and maintained the excellent enzymatic activity of catalase. Modification of Ce6@sAuNRs with THA resulted in efficient internalization of the nanocomposite into MCF-7/ADR multidrug-resistant (MDR) breast cancer cells (CD44+), thereby significantly enhancing the intracellular accumulation of the photosensitizer Ce6. CAT endows Ce6@sAuNRs with self-supporting oxygen production, which enables them to efficiently generate singlet oxygen (1O2) under 660 nm laser irradiation and enhances the photodynamic effect against hypoxic breast cancer cells. The results highlight the prospect of this novel multi-functional nanoplatform integrating active biological macromolecules (THA and CAT) into photosensitizer/photothermal gold nanocomposites in overcoming the limitations of hypoxic MDR breast cancer cell treatment.

Chitosan/sulfobutylether-ß-cyclodextrin based nanoparticles coated with thiolated hyaluronic acid for indomethacin ophthalmic delivery.

Indomethacin (IND) is topically administered for the treatment of the anterior segment diseases such as conjunctivitis, uveitis, and inflammation prevention for post-cataract surgery, as well as posterior segment diseases as macular edema. Currently IND is available as 0.1% w/v hydroxypropyl-ß-cyclodextrin-based eye drop formulation and its bioavailability is limited by several drawbacks such as the nasolacrimal duct draining, the reflex blinking and the low volume of the conjunctival sac. In this study, chitosan (CS)/sulfobutylether-ß-cyclodextrin (SBE-ß-CD) based nanoparticles (NPs) with a mean diameter of 340 (±7) nm, a ζ-potential value of +18.3 (±0.5) mV and coated with thiolated low molecular weight hyaluronic acid were formulated to improve both the solubility and the residential time in the conjunctival sac of the loaded drug IND. The NPs were prepared through the ionotropic gelation technique, exploiting the interaction between the positively charged amino group of CS and the negatively charged sulfonic group of SBE-ß-CD. The mucoadhesive properties of the NPs were evaluated on chicken trachea and esophagus tissues using a texture analyser. The irritability effects of NPs were disclaimed with Hecam test. The developed coated NPs showed increased residential time in the conjunctival sac, displayed no irritancy or toxicity for local administration, making them an optimal and innovative drug delivery system for the treatment of anterior segment inflammation diseases. On the other hand, the uncoated NPs displayed better permeating properties since they are smaller and could be further exploited for the treatment of posterior segment diseases.

Chemo-photothermal immunotherapy for eradication of orthotopic tumors and inhibition of metastasis by intratumoral injection of polydopamine versatile hydrogels.

Cancer remains one of the leading causes of death globally and metastasis always leads to treatment failure. Here, we develop a versatile hydrogel loading photothermal agents, chemotherapeutics, and immune-adjuvants to eradicate orthotopic tumors and inhibit metastasis by combinational therapy. Hydrogel networks were synthesized via the thiol-Michael addition of polydopamine (PDA) with thiolated hyaluronic acid. PDA acted as a cross-linking agent and endowed the hydrogel with excellent photothermal property. Meanwhile, a chemotherapeutic agent, doxorubicin (DOX), was loaded in the hydrogel via π‒π stacking with PDA and an immune-adjuvant, CpG-ODN, was loaded via electrostatic interaction. The release of DOX from the hydrogel was initially slow but accelerated due to near infrared light irradiation. The hydrogels showed remarkably synergistic effect against 4T1 cancer cells and stimulated plenty of cytokines secreting from RAW264.7 cells. Moreover, the hydrogels eradicated orthotopic murine breast cancer xenografts and strongly inhibited metastasis after intratumoral injection and light irradiation. The high anticancer efficiency of this chemo-photothermal immunotherapy resulted from the strong synergistic effect of the versatile hydrogels, including the evoked host immune response. The combinational strategy of chemo-photothermal immunotherapy is promising for highly effective treatment of breast cancer.

Thiolated hyaluronic acid/silk fibroin dual-network hydrogel incorporated with bioglass nanoparticles for wound healing.

Thiolated hyaluronic acid(THA) conjugates were synthesized and the selected THA was combined with silk fibroin(SF) and bioactive glass nanoparticles to build a novel type of composite hydrogel with dual-network structure. The optimally achieved gels showed greatly enhanced strength and stiffness compared to the gels built from either THA or SF while having well-defined elasticity and injectability. They were able to sustainably release Si ions in approximately linear manners for around three weeks. In vitro cell culture revealed that they supported the in-growth and proliferation of seeded cells, and showed the ability to markedly stimulate the migration of both fibroblasts and human umbilical vein endothelial cells. In vivo results based on the 10 mm mouse full-thickness skin defect demonstrated that they were able to fully restore the skin defects with formation of vascularized tissues and complete appendages during two weeks, suggesting their highly promising potency in use for wound healing.

Nanoparticle-driven self-assembling injectable hydrogels provide a multi-factorial approach for chronic wound treatment.

Chronic wounds represent a major health burden and drain on medical system. Efficient wound repair is only possible if the dressing materials target simultaneously multiple factors involved in wound chronicity, such as deleterious proteolytic and oxidative enzymes and high bacterial load. Here we develop multifunctional hydrogels for chronic wound management through self-assembling of thiolated hyaluronic acid (HA-SH) and bioactive silver-lignin nanoparticles (Ag@Lig NPs). Dynamic and reversible interactions between the polymer and Ag@Lig NPs yield hybrid nanocomposite hydrogels with shear-thinning and self-healing properties, coupled to zero-order kinetics release of antimicrobial silver in response to infection-related hyalurodinase. The hydrogels inhibit the major enzymes myeloperoxidase and matrix metalloproteinases responsible for wound chronicity in a patient's wound exudate. Furthermore, the lignin-capped AgNPs provide the hydrogel with antioxidant properties and strong antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. The nanocomposite hydrogels are not toxic to human keratinocytes after 7 days of direct contact. Complete tissue remodeling and restoration of skin integrity is demonstrated in vivo in a diabetic mouse model. Hematological analysis reveals lack of wound inflammation due to bacterial infection or toxicity, confirming the potential of HA-SH/Ag@Lig NPs hydrogels for chronic wound management. STATEMENT OF SIGNIFICANCE: Multifunctional hydrogels are promising materials to promote healing of complex wounds. Herein, we report simple and versatile route to prepare biocompatible and multifunctional self-assembled hydrogels for efficient chronic wound treatment utilizing polymer-nanoparticle interactions. Hybrid silver-lignin nanoparticles (Ag@Lig NPs) played both: i) structural role, acting as crosslinking nodes in the hydrogel and endowing it with shear-thinning (ability to flow under applied shear stress) and self-healing properties, and ii) functional role, imparting strong antibacterial and antioxidant activity. Remarkably, the in situ self-assembling of thiolated hyaluronic acid and Ag@Lig NPs yields nanocomposite hydrogels able to simultaneously inhibits the major factors involved in wound chronicity, namely the overexpressed deleterious proteolytic and oxidative enzymes, and high bacterial load.

An injectable micelle-hydrogel hybrid for localized and prolonged drug delivery in the management of renal fibrosis.

Localized delivery, comparing to systemic drug administration, offers a unique alternative to enhance efficacy, lower dosage, and minimize systemic tissue toxicity by releasing therapeutics locally and specifically to the site of interests. Herein, a localized drug delivery platform ("plum‒pudding" structure) with controlled release and long-acting features is developed through an injectable hydrogel ("pudding") crosslinked via self-assembled triblock polymeric micelles ("plum") to help reduce renal interstitial fibrosis. This strategy achieves controlled and prolonged release of model therapeutics in the kidney for up to three weeks in mice. Following a single injection, local treatments containing either anti-inflammatory small molecule celastrol or anti-TGFß antibody effectively minimize inflammation while alleviating fibrosis via inhibiting NF-κB signaling pathway or neutralizing TGF-ß1 locally. Importantly, the micelle-hydrogel hybrid based localized therapy shows enhanced efficacy without local or systemic toxicity, which may represent a clinically relevant delivery platform in the management of renal interstitial fibrosis.

Synthesis and characterization of biphasic calcium phosphate laden thiolated hyaluronic acid hydrogel based scaffold: physical and in-vitro biocompatibility evaluations.

The present study focused on the combination of biphasic calcium phosphate (BCP) nanoparticles into the modified hyaluronic acid based injectable hydrogels for bone tissue engineering. Self-cross-linked thiolated hyaluronic acid (HA-HS) injectable hydrogels loaded with biphasic calcium phosphate (BCP) nanoparticles were prepared by disulfide cross-linking to mimic the extracellular matrix as a potential material for bone treatment. Varying concentration of HA-HS ranging between 1 and 5w/v% was tested to optimize the optimum concentration and were further modified with varying BCP concentrations for final optimization. Physico-chemical characterizations of the prepared hydrogel such as SEM, EDS, FT-IR, and XRD confirmed that the BCP has effectively loaded and distributed homogeneously in the HA-HS hydrogel. The results showed that the 3% (w/v) HA-HS hydrogel exhibits the appropriate properties for injectable hydrogel system such as gelation times, swelling rate and in vitro degradation behavior among all tested concentrations. Cell viability and cell proliferation using osteoblast cells (MC3T3-E1) demonstrated that the BCP laden modified hydrogel are biocompatible in vitro. In light of the encouraging results obtained, BCP laden HA-HS hydrogels might offer the potential to be used as injectable hydrogel in bone tissue engineering.

S-protected thiolated hyaluronic acid: In-situ crosslinking hydrogels for 3D cell culture scaffold.

The purpose of this study was to synthesize S-protected thiolated hyaluronic acid (HA) and to evaluate its potential for 3D cell culture scaffold. S-protected thiolated HA was synthesized by the covalent attachment of N-acetyl-S-((3-((2,5-dioxopyrrolidin-1-yl)oxy)-3-oxopropyl)thio)cysteine hydrazide ligand to the HA. Hydrogels were characterized for texture, swelling behavior and rheological properties. Furthermore, the potential of S-protected thiolated HA hydrogels as a scaffold for tissue engineering was evaluated by cell proliferation studies with Caco-2 and NIH 3T3 cells. It showed enhanced cohesion upon addition of N-acetyl cysteine (NAC). Dynamic viscosity of S-protected thiolated HA hydrogel was increased up to 19.5-fold by addition of NAC and 10.1-fold after mixing with mucus. Furthermore, Caco-2 and NIH 3T3 cells encapsulated into hydrogels proliferated in-vitro. As this novel S-protected thiolated HA is stable towards oxidation and forms highly cohesive gels when getting into contact with endogenous thiols due to disulfide-crosslinking, it is a promising tool for 3D cell culture scaffold.

Injectable self-crosslinking HA-SH/Col I blend hydrogels for in vitro construction of engineered cartilage.

The injectable self-crosslinking blend hydrogel by combination of collagen I and thiolated hyaluronic acid could alleviate collagen I contraction in vitro and overcome weak cell adhesive sites of hyaluronic acid. Five groups of injectable hydrogels with different ratios were prepared to investigate their gelation time, injection force, mechanical properties, swelling capacity and disintegration performance. These results indicated that Col7HA-SH3 hydrogel achieved the optimal controlled and injectable effect, the gelation time was just ten seconds with injection force at 3.5 N, and the storage modulus of hydrogel could reach 11 kPa with frequency at 10 Hz. Furthermore, the phenotype maintaining, biocompatibility and chondrocytes proliferation were administrated by CLSM, SEM, histological staining, immuohistochemical staining, MTT test and glycoaminoglycans quantification. Similarly, the Col7HA-SH3 blend hydrogel encapsulated chondrocytes presented most excellent proliferation potential, phenotype maintaining, biocompatibility and convenient operational characteristics. These findings might approach the underlying clinical application of blend hydrogel in cartilage repair.

Thiolated Hyaluronic Acid as Versatile Mucoadhesive Polymer: From the Chemistry Behind to Product Developments-What Are the Capabilities?

Within the last decade, intensive research work has been conducted on thiolated hyaluronic acids (HA-SH). By attaching sulfhydryl ligands onto naturally occurring hyaluronic acid various types of HA-SH can be designed. Due the ability of disulfide bond formation within the polymer itself as well as with biological materials, certain properties such as mucoadhesive, gelling, enzyme inhibitory, permeation enhancing and release controlling properties are improved. Besides the application in the field of drug delivery, HA-SH has been investigated as auxiliary material for wound healing. Within this review, the characteristics of novel drug delivery systems based on HA-SH are summarized and the versatility of this polymer for further applications is described by introducing numerous relevant studies in this field.

Stimuli-sensitive thiolated hyaluronic acid based nanofibers: synthesis, preclinical safety and in vitro anti-HIV activity.

AIM: To develop a seminal enzyme bioresponsive, mucoadhesive nanofibers (NFs) as safe and effective nanocarriers for the prevention of HIV vaginal transmission. METHODS: A novel thiolated hyaluronic acid (HA-SH) polymer was synthesized to fabricate tenofovir (TFV)-loaded electrospun NFs (HA-SH-NFs) and characterized in vitro/in vivo. RESULTS: A triggered drug release (87% w/w) from the engineered HA-SH-NFs (mean diameter ∼75 nm) occured within 1 h under the influence of seminal hyaluronidase enzyme. HA-SH-NFs were noncytotoxic, induced no damage on the C57BL/6 mice genital-tract and other organs. No significant CD45 cell-infiltration and changes in cytokines level in cervicovaginal tissues were observed. HA-SH-NFs significantly enhanced both TFV retention and bioavailability in vaginal tissue compared with the 1% TFV-gel. The anti-HIV activity of TFV (on pseudotyped virus followed by luciferase assay) was not adversely affected by the electrospinning process. CONCLUSION: HA-SH-NFs developed in this study could potentially serve as a safe nanotemplate for topical intravaginal delivery of HIV/AIDS microbicides.

The self-crosslinking smart hyaluronic acid hydrogels as injectable three-dimensional scaffolds for cells culture.

Although the disulfide bond crosslinked hyaluronic acid hydrogels have been reported by many research groups, the major researches were focused on effectively forming hydrogels. However, few researchers paid attention to the potential significance of controlling the hydrogel formation and degradation, improving biocompatibility, reducing the toxicity of exogenous and providing convenience to the clinical operations later on. In this research, the novel controllable self-crosslinking smart hydrogels with in-situ gelation property was prepared by a single component, the thiolated hyaluronic acid derivative (HA-SH), and applied as a three-dimensional scaffold to mimic native extracellular matrix (ECM) for the culture of fibroblasts cells (L929) and chondrocytes. A series of HA-SH hydrogels were prepared depending on different degrees of thiol substitution (ranging from 10 to 60%) and molecule weights of HA (0.1, 0.3 and 1.0 MDa). The gelation time, swelling property and smart degradation behavior of HA-SH hydrogel were evaluated. The results showed that the gelation and degradation time of hydrogels could be controlled by adjusting the component of HA-SH polymers. The storage modulus of HA-SH hydrogels obtained by dynamic modulus analysis (DMA) could be up to 44.6 kPa. In addition, HA-SH hydrogels were investigated as a three-dimensional scaffold for the culture of fibroblasts cells (L929) and chondrocytes cells in vitro and as an injectable hydrogel for delivering chondrocytes cells in vivo. These results illustrated that HA-SH hydrogels with controllable gelation process, intelligent degradation behavior, excellent biocompatibility and convenient operational characteristics supplied potential clinical application capacity for tissue engineering and regenerative medicine.

Conjugating an anticancer drug onto thiolated hyaluronic acid by acid liable hydrazone linkage for its gelation and dual stimuli-response release.

A prodrug gelation strategy was developed for the sustained and dual stimuli-response release of doxorubicin hydrochloride (DOX·HCl), a commonly used anticancer drug. For this purpose, the chemical conjugation of DOX·HCl onto thiolated hyaluronic acid (HA) was carried out by an acid liable hydrazone linkage and verified by (1)H NMR analyses. When exposed to the air, such a polysaccharide conjugate showed unique self-gelation ability in aqueous solution. The gelation time and extent depended mainly on the content of thiol groups on thiolated HA. The resultant hydrogel exhibited a dominant elastic response and a thixotropic property. In particular, it could release sustainably conjugated DOX·HCl in dual pH- and reduction-responsive modes. The cumulative drug release was found to be significantly accelerated under the conditions mimicking the intracellular environments of cancer cells. The in vitro cytotoxicity assays for the human nasopharyngeal carcinoma CNE2 cells treated with various release media confirmed the effectiveness of this conjugate hydrogel for cancer cell inhibition.