Hyaluronic Acid

Abstract

Topical application of antibiotics in the treatment of orthopaedic implant-related infections can be achieved by using hyaluronic acid (HA)-based hydrogels as carriers. Our aim was to investigate potential toxic effects of a novel antibiotic-loaded hydrogel on osteogenic cells and its antibacterial effect against staphylococci. A covalently cross-linked hyaluronic acid (HA)-based hydrogel was loaded with increasing concentrations of cefuroxime and vancomycin and their release was examined by UV spectrometry. Primary human (HoBs), mouse (MoBs) osteoblasts, or SaoS-2 cells were either exposed to the drug-loaded hydrogel or to antibiotics alone, followed by assessment of cell metabolism and proliferation. Antibacterial effects were evaluated against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis). Increasing concentrations of antibiotics did not affect cell metabolism in any osteogenic cell type, whereas cell proliferation remained unaltered in MoBs, was significantly reduced in SaoS-2, and was stimulated in HoBs. Cultures of MoBs and HoBs tolerated higher concentrations of vancomycin than SaoS-2. Antibiotic-loaded hydrogels did not exert toxic effects on HoBs. After 24 h, 16.8% of vancomycin and 70.8% of cefuroxime were released from the hydrogel. Cefuroxime-loaded hydrogels significantly inhibited growth of S. aureus but not of S. epidermidis, while vancomycin-loaded hydrogel had scarce effects on S. epidermidis. Loading HA-based hydrogel with antibiotics does not harm osteoblasts at clinically relevant concentrations but inhibits bacterial growth. Higher loading of vancomycin may be required due to its slow release while cefuroxime is released more rapidly. A resorbable, antibiotic-loaded hydrogel may be used for implant-related infections in orthopaedics.

Abstract

Peptide-drug conjugates (PDCs) offer a powerful therapeutic modality by integrating the targeting specificity of peptides with the cytotoxic efficacy of chemotherapeutics, thereby improving antitumor performance while reducing off-target toxicity. In this study, we engineered biometallic PDCs composed of peptide nanofibers (PNFs), gold nanoparticles (GNPs), and doxorubicin (DOX), termed PGDCs, and incorporated them into photo-responsive dual-network hyaluronic acid hydrogels for combined photothermal and chemotherapeutic (PTT/CT) treatment of breast cancer. The hydrogel was formed by mixing oxidized methacrylated hyaluronic acid (O-HAMA) with PGDCs, followed by rapid photo-crosslinking under 365 nm UV light, achieving gelation within 90 s for localized, on-demand drug deployment. The resulting O-HAMA/PGDC hydrogels exhibited pH-responsive drug release under tumor microenvironments and robust photothermal performance under NIR irradiation. In vitro and in vivo evaluations revealed strong tumor suppression, with 98% inhibition efficiency, effective tumor ablation, and minimal damage to surrounding healthy tissues. The structural modularity of PGDCs-allowing simultaneous integration of metals, peptides, and drugs-opens pathways for designing highly effective, tumor-selective nanotherapeutics with controlled activation, efficient internalization, and combined therapeutic outcomes.

Abstract

Biomaterial-based skeletal muscle tissue engineering approaches have largely focused on mimicking the 3D aligned architecture of native muscle, which is critical for guiding myotube formation and force transmission. In contrast, fewer studies incorporate glycosaminoglycan (GAG)-mediated biochemical cues despite their known role in regulating myogenesis and growth factor sequestration. In this study, we develop aligned collagen-GAG (CG) scaffolds using directional freeze-drying and systematically vary GAG type by incorporating GAGs of increasing sulfation levels (hyaluronic acid, chondroitin sulfate, and heparin). While all scaffold variants support myoblast adhesion, metabolic activity, and myotube alignment, heparin-modified CG scaffolds significantly enhance myoblast metabolic activity and myogenic differentiation as measured by myosin heavy chain (MHC) expression and myotube size. We additionally show that heparin-modified scaffolds sequester and retain significantly higher levels of insulin-like growth factor-1 (IGF-1), a potent promoter of myogenesis, compared to other scaffold groups. Together, these results highlight the importance of tailoring GAG type in CG scaffolds for targeted applications and underscore the promise of heparin-modified CG scaffolds as a material platform for skeletal muscle tissue engineering.

Abstract

During the perioperative period, increased vascular permeability is associated with elevated morbidity and mortality. Obstructive jaundice (OJ) has been demonstrated to increase vascular permeability. The endothelial glycocalyx (EG), comprising hyaluronic acid (HA), chondroitin sulfate (CS), and syndecan-1 (SDC1), is essential for vascular integrity. However, its role in OJ-related vascular dysfunction remains unclear. This study aimed to investigate whether EG degradation contributes to vascular hyperpermeability in OJ patients. Plasma was preoperatively collected from 35 OJ patients and 33 non-jaundiced controls. EG components (HA, CS, SDC1) and vascular permeability-related mediators, including vascular endothelial growth factor (VEGF), thrombin, sphingosine-1-phosphate, atrial natriuretic peptide, cyclic adenosine monophosphate, and nitric oxide (NO) were quantified. Transendothelial electrical resistance was used to assess endothelial permeability. OJ patients showed significantly increased vascular permeability, which correlated with elevated levels of HA, CS, and SDC1. Concurrently, plasma levels of VEGF, thrombin, atrial natriuretic peptide, and NO were elevated, while the endothelial-stabilizing mediator cyclic adenosine monophosphate was reduced, indicating synergistic EG breakdown and dysregulation of permeability pathways. This study confirms that EG degradation is associated with OJ-induced vascular hyperpermeability. Targeting EG integrity may offer a therapeutic strategy to improve perioperative outcomes, though further studies are needed to establish causality.

Abstract

Ischemia-reperfusion injury is a key driver of acute kidney injury, characterized by mitochondrial reactive oxygen species (mtROS) generation. However, the lack of targeted mitochondrial scavenging mechanisms exacerbates the deleterious effects of mtROS. Here, we report the development of a mitochondria-targeted hollow mesoporous manganese oxide nanozyme, cofunctionalized with hyaluronic acid and the mitochondria-targeting peptide SS31 (HMN@HA-SS31), to enhance the catalytic activity within kidney proximal tubular epithelial cells (PTECs) and their mitochondria. HMN@HA-SS31 was synthesized through templated shell growth and orthogonal ligations, resulting in broad multi-ROS scavenging capabilities with superoxide dismutase (SOD)- and catalase (CAT)-like activities, as well as preferential mitochondrial localization. In H2O2-challenged human kidney (HK-2) cells, HMN@HA-SS31 reduced mtROS, restored membrane potential and network integrity, and significantly decreased apoptosis. In a murine I/R-AKI model, HMN@HA-SS31 traversed the compromised filtration barrier, accumulated in damaged PTECs, reduced renal ROS, improved kidney function and histopathology, inhibited the cGAS-STING pathway, limited fibrosis under a multidose regimen, and increased 21-day survival to 80% without detectable toxicity. These findings suggest that mitochondrial targeted enables localized catalysis within mitochondrial microdomains, thereby disrupting the mtROS-inflammation cycle in I/R-AKI. This study introduces a mitochondrial targeted antioxidant strategy, providing insights into the development of therapeutics for I/R-AKI.

Abstract

Portal hypertension (pH) is a major determinant of complications associated with chronic liver disease, and high-risk varices (HRV) require prophylactic intervention. Hepatic venous pressure gradient (HVPG) measurement is the gold standard for assessment. However, it is invasive. This study examined the most reliable noninvasive biomarker for evaluating HVPG and diagnosing HRV.

Abstract

Current clinical management of diarrhea-predominant irritable bowel syndrome (IBS-D) faces substantial challenges due to the limited efficacy of existing therapeutic strategies. This study aimed to synthesize and characterize the hyaluronic acid-ethylenediamine-cinnamic acid conjugate (HA-EDA-CA), investigate its oral bioavailability and colonic tissue distribution, and validate its therapeutic potential along with underlying mechanisms of action in IBS-D models. Following oral administration of free CA or HA-EDA-CA, the colon concentration of CA released from the derivative was significantly higher than that of free CA alone. Both free and conjugated forms of CA likely contributed to the therapeutic effects against IBS-D. The IBS-D model was established by a combination of senna decoction administration and physical restraint stress. After HA-EDA-CA intervention, IBS-D model mice showed marked improvements in stool consistency, fecal water content, stool output, body weight, visceral hypersensitivity, and colon length. ELISA results indicated significant reduction in enteric neurotransmitter levels, including 5-hydroxytryptamine, substance P, and vasoactive intestinal peptide, after oral gavage administration of HA-EDA-CA. Additionally, intestinal permeability assessment and immunofluorescence analyse revealed that HA-EDA-CA improved intestinal barrier function. Western blot analysis indicated HA-EDA-CA inhibited 5-hydroxytryptamine signaling pathway. Furthermore, HA-EDA-CA modulated gut microbiota composition. These findings suggested the potential of HA-EDA-CA as a promising therapeutic candidate for IBS-D treatment. KEY NOVELTIES:.

Abstract

It is now appreciated that CD154 and CD40 may be differentially effective as therapeutic targets in transplantation owing to the ability of CD154 to bind to a second receptor, CD11b. We previously reported that the combination of anti-CD40 and a specific CD154:CD11b blocker enhanced allograft survival compared to anti-CD40 alone. In the current study, we have utilized a novel nanoparticle-based approach to more effectively deliver CD154:CD11b blockade during transplantation. Recipients of allogeneic skin grafts were treated with either CTLA-4Ig or the combination of CTLA-4Ig plus a hyaluronic acid nanoparticle-conjugated CD154:CD11b peptide inhibitor (iPepHANP). Results indicated that iPepHANP synergized with CTLA-4Ig in prolonging allograft survival and inhibiting donor-reactive CD4+ and CD8+ T cell responses. Specifically, frequencies of donor-reactive CD4+ and CD8+ T cells in the spleen were significantly reduced in iPepHANP+CTLA-4Ig-treated animals as compared to CTLA-4Ig alone. Moreover, iPepHANP+CTLA-4Ig administration significantly reduced donor-reactive CD4+ T cell and activated CD8+ T cell infiltration into skin allografts compared to CTLA-4Ig alone. Notably, mice treated for 100 days with the CD154:CD11b blocking nanoparticle demonstrated sustained transplantation tolerance following secondary graft rechallenge in the absence of any further immunosuppression. Taken together, these data highlight the potential of CD154:CD11b-blocking nanoparticles as a therapeutic strategy in transplantation.

Abstract

Type 1 diabetes (T1D) is driven by autoreactive T cells, which destroy insulin-producing β cells. Antigen-specific immunotherapies (ASITs) aim to restore immune tolerance while avoiding the broad immunosuppression of current therapies. Soluble antigen arrays (SAgAs) are multivalent antigen constructs built on a low-molecular-weight hyaluronic acid (HA) backbone, previously validated in preclinical models. Here, we generated SAgAs displaying human T1D autoantigen epitopes, including Insulin B:9-23 (InsB:9-23) and a hybrid insulin peptide (HIP), alongside a hemagglutinin (HAg):306-318 control. We confirmed their structure, valency, and ability to engage human epitope-specific T cell clones. Both InsB:9-23-SAgA and HIP-SAgA demonstrated strong specificity, supporting their utility as T cell probes and potential candidates for ASIT in T1D.

Abstract

Protease-catalyzed synthesis of a peptide composed of l-tyrosine and l-phenylalanine (2.2:1 M ratio) was achieved in a natural deep eutectic solvent (NADES) medium and subsequently employed to encapsulate the anti-inflammatory cytokine interleukin-10 (IL-10). IL-10 was loaded into enzyme-mediated peptide nanocrystals at doses of 200 and 400 ng, achieving stable nanocomposite formulations. Release studies were conducted in phosphate-buffered saline (PBS, pH 7.4) at 37°C under gentle agitation, revealing a sustained release profile extending up to 30-31 days, with an initial release of approximately 16% within the first 5 days and near-complete release between Days 10 and 25, depending on loading. Encapsulation effectively protected IL-10 from rapid degradation observed for the free cytokine under identical conditions, resulting in markedly enhanced stability. The nanocrystals were further integrated into porcine gelatin-hyaluronic acid (Ge:HA) and microbial poly(hydroxybutyrate-co-valerate) (PHBV) matrices, where IL-10 release was further modulated, reaching up to ~80% release from Ge:HA and ~100% from PHBV-based systems over 31 days. Cytotoxicity assays using primary human dermal fibroblasts confirmed excellent biocompatibility of all formulations. Moreover, studies in PMA-activated THP-1 macrophage-like cells demonstrated reduced intracellular reactive oxygen species (ROS) and suppression of the pro-inflammatory cytokine IL-6, highlighting the combined protective and immunomodulatory effects of IL-10 encapsulation. The presence of tyrosine residues within the nanocarrier further suggests intrinsic antioxidant contributions. Overall, these results support enzyme-mediated peptide nanocrystals as an effective platform for the stabilization and prolonged release of IL-10, with strong potential for treating inflammation-related skin conditions.

Abstract

Spinal cord injury (SCI) initiates a cascade of pathological events in which neuroinflammation and hypoxia critically impair functional recovery. Although exogenous carbon monoxide (CO) exhibits anti-inflammatory potential, its translation has been hindered by the lack of a safe and effective delivery strategy. Here, we report the development of a multifunctional therapeutic platform (COPH), composed of CO-releasing molecules-401 (CORM-401) as the CO donor, peptide dendrimer nanogels (PDNs) as the carrier, and hyaluronic acid (HA) as a microglia-targeting ligand. COPH selectively accumulates in microglia, where it responds to elevated reactive oxygen species (ROS) by releasing CO and simultaneously scavenging excessive ROS. In vitro and in vivo studies demonstrate that COPH suppresses pro-inflammatory mediators such as IL-1β and CD86 via inhibition of the NF-κB/p65 pathway, while promoting M1-to-M2 microglial polarization. Moreover, CO released from COPH alleviates local hypoxia by modulating hemoglobin-oxygen binding dynamics, thereby enhancing oxygen availability to neurons and vascular cells in ischemic regions. Through activation of the Nrf2/HO-1 antioxidant pathway, COPH further mitigates oxidative stress and reduces neuronal apoptosis. Collectively, these findings highlight COPH as a targeted CO delivery system that attenuates inflammation, relieves hypoxia, and protects neurons after SCI, providing a promising strategy for CO-based therapeutics in neurotrauma.

Abstract

Prosthetic joint infection (PJI) is a major adverse outcome following total hip and knee arthroplasties. With the rise of antimicrobial resistance, there is a risk of therapeutic insufficiency in treating PJI. This study determined the potential of a poly-ε-lysine and hyaluronic acid (PEL-10/HA144-1) contact-killing coating as a promising prevention of bacterial attachment. A broader development perspective was integrated through a Safe-by-Design approach by adding relevant in vitro tests for implant-host interactions. The PEL-10/HA144-1 coating was deposited on titanium alloy Ti6Al4V (Ti) and ultra-high-molecular-weight-polyethylene (UHMWPE). A combination of the ISO 22196, ASTM E2180-18, and JIS Z 2801 testing standards using Staphylococcus aureus and Escherichia coli demonstrated a bactericidal effect of the coating, up to a 5-log reduction compared to uncoated samples. A bacterial adhesion test showed a decrease in adherent bacteria up to 4-log after 4 h, and up to 5-log after 24 h between coated and uncoated samples. Saos-2 human osteoblast-like cells and L929 mouse fibroblasts exposed to 72 h extracts of the coating for 24 h showed in vitro cell viability of >70%, indicating no cytotoxicity according to ISO 10993-5. Furthermore, while initial osteoblast attachment to the coating appeared challenging, increased proliferation and metabolic activity over time were observed. After 14 and 21 days, no reduction in osteogenic marker expression was found on the coated samples compared to the uncoated samples. Overall, the PEL-10/HA144-1 coating reduced bacterial adhesion, was not cytotoxic to mammalian cells, and supported osteoblast function in vitro, making it a promising technique for future implantable orthopedic applications.

Abstract

Oral administration of peptide-based drugs offers improved patient compliance compared to injectable formulations. However, this route is hindered by several physiological barriers like enzymatic degradation, poor intestinal permeability, and low absorption in the gastrointestinal tract. To address these challenges, a novel virus-mimicking nanocarrier was developed for the oral delivery of liraglutide. Hollow mesoporous silica nanoparticles (HMSN) were synthesized via a co-condensation method and subsequently functionalized with a positively charged cell-penetrating peptide (CPP; KLPVM) to facilitate transcellular transport, and with negatively charged hyaluronic acid (HA) to enhance mucus penetration and enable receptor-mediated targeting. Liraglutide was efficiently encapsulated within HMSN matrix, achieving an encapsulation efficiency of 96.16% and a drug loading of 19.23%. In vitro release studies showed pH-responsive behavior, with limited release under acidic gastric conditions (7%) and sustained release at near-neutral intestinal pH (77% over 12 h). Cellular uptake studies revealed enhanced internalization of the HMSN-CPP@HA (98.1%), predominantly via caveolae-mediated endocytosis. Ex vivo intestinal permeability studies further confirmed improved transmucosal transport, with permeability increasing from 34.4% for MSNs to 97.6% for HMSN-CPP@HA. Pharmacodynamic evaluation in streptozotocin-induced diabetic rat models showed that oral administration of liraglutide-loaded virus-mimicking HMSNs resulted in a 50.98% reduction in fasting blood glucose and a 14.6% decrease in body weight over 28-day period. These outcomes were comparable to those achieved via subcutaneous liraglutide administration (62.7% and 19.2% respectively). These findings suggest that HMSN-CPP@HA preserve the biological activity of liraglutide during gastrointestinal transit, enhance intestinal absorption, and mimic viral translocation mechanisms, representing a promising platform for non-invasive oral delivery of peptide drugs.

Abstract

Infections caused by bacterial colonization and biofilm formation on wounds and dressings present critical challenges to wound care, often impeding healing. Here, we report an antibiotic-free preventive strategy based on medical fabric coated with supramolecular antimicrobial assemblies. Using layer-by-layer dip coating technique, we functionalized medical fabric with polyarginine (PAR30) and hyaluronic acid (HA144) polymers, biopolymers that synergistically exhibited intrinsic antimicrobial activity. Coatings deposition and structural integrity were validated by confocal microscopy and ATR-FTIR spectroscopy. Antibacterial performance was assessed using the AATCC100 standard test method, showed strong efficacy against both Gram-negative and Gram-positive clinical pathogens. In vivo wound infection models, employing bioluminescent methicillin-resistant Staphylococcus aureus (MRSA), were used to evaluate biofilm prevention. Coated and uncoated fabrics were either pre-inoculated with MRSA or applied to pre-infected wounds to assess their antimicrobial and anti-biofilm effects. The coated fabrics showed potent antibacterial activity, achieving ≥6 log-reduction in bacterial load within 24 h compared to uncoated fabrics. Bioluminescence imaging confirmed infection development in wounds covered with uncoated fabrics, while coated fabrics prevented infection with a ≥6 log-reduction in bacterial load on fabrics and a ≥4 log-reduction in wound biopsies. Additionally, coated fabrics inhibited biofilm formation and bacterial proliferation in wound beds inoculated with MRSA. Comprehensive in vitro and in vivo biocompatibility assessments demonstrated the safe profile of the coated fabrics for clinical use. These findings highlight the antimicrobial efficiency of coated fabrics in minimizing bacterial colonization and biofilm formation on wounds and textiles. This safe and effective first-in-class, innovative approach offers a promising preventive strategy against biofilm formation and addresses antimicrobial-resistant strains like MRSA in wound care.

Abstract

Osteoarthritis (OA) is a prevalent chronic pain syndrome and a leading cause of disability worldwide, characterized by progressive deterioration of articular cartilage. This degradation leads to pain, swelling, inflammation, and eventual stiffness as the cartilage wears down, causing bone-on-bone friction. Current medical treatments primarily aim at pain relief; however, many interventions, especially invasive or surgical ones, carry risks of adverse outcomes. Consequently, intra-articular (IA) therapy, particularly hyaluronic acid (HA) injections, is widely adopted as a conservative treatment option. HA plays a crucial role in maintaining joint homeostasis by supporting proteoglycan synthesis and scaffolding, restoring optimal HA concentrations in synovial fluid, and providing chondroprotective and anti-inflammatory effects. In recent years, hydrogels composed of natural and synthetic materials have emerged as promising candidates for OA treatment. Our research focuses on the biosynthesis and characterization of novel hydrogel composites combining short peptide hydrogelators with aminated graphene oxide (a-GO) nanosheets functionalized with HA (a-GO-HA@Hgel). These a-GO-HA@Hgel nanocomposites are designed to facilitate the controlled release of HA into the extracellular matrix, aiming to promote cartilage regeneration and mitigate inflammation. The strategy is to exploit the oxygen-containing functional groups of GO nanosheets to enable covalent coupling or physical adsorption of HA molecules through various chemical approaches. The resulting a-GO-HA are incorporated within hydrogel matrices to achieve sustained and controlled HA release. We study the influence of a-GO-HA on the native hydrogel structure and its viscoelastic properties, which are critical for mimicking the mechanical environment of native cartilage tissue. Through this multidisciplinary approach combining advanced materials science and cellular biology, this work aims to develop innovative nanocomposite hydrogels capable of delivering HA in a controlled manner, enhancing cartilage repair and providing a potential therapeutic strategy for OA management.

Abstract

Acute respiratory distress syndrome (ARDS) is a fatal inflammatory lung disorder with few effective treatments. Hyaluronan (HA), a major extracellular matrix component, exhibits diverse biological activities depending on its molecular weight. This study aimed to evaluate the therapeutic potential of HA of various molecular weights in a rat model of ARDS. ARDS was induced in rats via the intratracheal instillation of 5 mg of bleomycin. Seven days later, when ARDS symptoms developed, low (LHA), medium (MHA), high (HHA), and mixed (MIX HA) hyaluronan were intratracheally administered seven times from Days 7 to 28. On Day 7, arterial oxygen saturation (SpO2) and the partial pressure of oxygen (PaO2) decreased, carbon dioxide levels increased, the respiratory rate increased, and extensive lung cell infiltration was observed, confirming successful ARDS induction. LHA and MIX HA improved the SpO2 and PaO2, and the latter increased lung and alveolar volume, reduced infiltration, and normalized breathing. All HA types attenuated collagen deposition and M1 macrophage activity, while MIX HA enhanced M2 polarization and upregulated MMP-2, MMP-9, and TLR-4. LHA increased VEGF and EGF expression. These findings demonstrate that different-weight HAs provide partial ARDS protection via distinct mechanisms. MIX HA shows synergistic effects, restoring and improving lung structure and function, respectively, representing a promising ARDS therapy.

Abstract

Current studies have shown that the asialoglycoprotein receptor 1 (ASGR1) is involved in glycolipid metabolism and is associated with systemic insulin resistance. This study aims to explore the correlation between serum soluble ASGR1 (sASGR1) levels and metabolic dysfunction-associated steatotic liver disease (MASLD) by assessing the relationship between sASGR1 concentrations and various biomarker levels.

Abstract

Mesenchymal stem cell (MSC) therapy shows potential in regenerative medicine, particularly in treating osteoarthritis (OA). MSCs injected into the joint can secrete growth factors and extracellular matrix molecules, contributing to paracrine communication and cartilage regeneration. However, in the non-vascularized joint environment, MSCs lacking nutrient supply, starve and die too quickly to efficiently deliver enough of these factors. We have recently synthesized a new hydrogel containing hyaluronic acid and glucose (HA-GLC). This hydrogel allows MSCs to survive and proliferate in an environment with otherwise low glucose levels. Furthermore, it releases glucose through enzymatic cleavage by ß-glucosidase, an enzyme which we have shown to be available and active in human bone marrow mesenchymal stem cells (BM-MSCs). In this study, we did incorporate MSCs to this HA-GLC hydrogel. Proteomic analysis of the MSC secretome revealed that glucose deprivation modified the profile of secreted factors, inducing changes in several key pathways, including extra-cellular matrix production. We then tested the effect of glucose deprivation in MSC secretome on human chondrocyte (hCH) proliferation and IL-6 secretion. Our results showed an increase in hCH proliferation and a significant decrease in IL-6 expression, when cells were exposed to the secretome of MSCs cultured in glucose-provided media rather than glucose-deprived conditions. These findings highlighted the ability of this new technology (HA-GLC hydrogel) to modulate the MSC secretome function, potentially enhancing cartilage regeneration in OA.

Abstract

Polymer-drug conjugates nanoparticles have become an advanced strategy in drug delivery for fighting against cancer. Herein, a glutathione (GSH) responsive polyaspartic acid-drug conjugates nanoparticles coated by amino-functionalized hyaluronic acid (PCDH) were innovatively fabricated for anticancer drug delivery. The obtained amphiphilic polymers self-assembled into spherical nanoparticles in water with size of 318.9 ± 1.9 nm and exhibited excellent stability. Intriguingly, this system demonstrated that the fluorescence of DOX was quenched, but upon encountering the rich endogenous GSH in tumor cells will be activated and dissociated DOX and restored its fluorescence rather than in normal cells, which endowed the PCDH with tumor-selective uptake performance while exhibited specific chemotherapy. Meanwhile, the endogenous GSH was consumed to disrupt the redox homeostasis within tumor cells to further promote cell death. Notably, by intravenous injection of PCDH into 4T1 tumor-bearing mice, the PCDH can precisely accumulate at the tumor and efficiently controlled tumor growth with negligible toxicity, resulting in a 5-fold reduction in tumor volume compared to the saline group and a 2-fold reduction compared to the free drug group. These findings indicated that the PCDH nanoparticles held great promise as an antitumor drug delivery system for cancer diagnosis and therapy.

Abstract

Antigen presentation to autoreactive T cells in the pancreatic islets by dendritic cells and B lymphocytes is paramount to the pathogenesis of Type 1 diabetes (T1D). Immunosuppressive therapies, such as rituximab (anti-CD20) and teplizumab (anti-CD3), can delay T1D onset; however, risks associated with B or T cell depletion, such as an increased susceptibility to infections, are considerable. Antigen-specific immunotherapy (ASIT) offers a more targeted approach to suppress or delete the autoreactive cells, specifically recognizing autoantigens associated with disease. Soluble antigen arrays (SAgAs) are a platform consisting of a hyaluronic acid (HA) backbone and multiple copies of the autoantigen to selectively suppress autoreactive B cells and T cells. Here, a new SAgA was developed by conjugating a mutated proinsulin antigen (proinsulin(F25D)) to HA (SAgAM-PI(F25D)) to avoid glycemic activity while retaining the ability to target anti-insulin antibodies and B cells. SAgAM-PI(F25D) had a pronounced reduction in insulin receptor-β activity and lacked glycemic activity in vivo. Furthermore, this SAgA successfully bound a disease-relevant monoclonal anti-insulin antibody with low nanomolar binding affinity and murine transgenic (Tg125) B cells specific for human insulin. This collection of data demonstrated the avoidance of glycemic effects of proinsulin SAgAs while retaining specificity to anti-insulin antibody and insulin-binding B cells, thus highlighting the potential as a candidate for intervening in T1D as an ASIT.

Abstract

Rheumatoid arthritis (RA) tissues exhibit high levels of reactive oxygen species (ROS) and free Ca2+, which contribute to a vicious cycle of sustained inflammatory responses. This study developed an in situ Ca2+-reinforced injectable full-active HPAP hydrogel. The full-active hydrogel is formed by cross-linking phenylboronic acid-functionalized hyaluronic acid (HA-PBA) with sodium alginate (ALG) and paeoniflorin (PF) through boronate ester bonds, all of which play significant roles in RA treatment. HPAP hydrogel exhibits relatively low strength in vitro, allowing for easy injection into the joint cavity. Then, ALG can trigger secondary cross-linking in the RA joint cavity using Ca2+, forming the HPAP/Ca2+ hydrogel in situ and enhancing drug retention (with significant signals detectable in vivo even 17 days postinjection). Furthermore, a decrease in the free Ca2+ concentration can inhibit the activation of the NLRP3 inflammasome pathway. HA-PBA participates in the formation of ROS-responsive boronate ester bonds in hydrogel, thereby reducing ROS levels in RA tissues. Additionally, the released PF inhibits the activation of the NF-κB pathway, mitigating the inflammatory response. In vitro and in vivo experiments demonstrate that the HPAP hydrogel can effectively scavenge ROS, inhibit the NF-κB and NLRP3 pathways, reprogram macrophages, and reduce osteoclast differentiation and cartilage matrix degradation. In the RA animal models, HPAP hydrogel significantly improved arthritis scores, bone erosion, and inflammation levels, showing better treatment efficacy compared to commercial dexamethasone. Given the simplicity of the components of this full-active hydrogel, all of which are natural and safe compounds, it exhibits promising clinical translation potential in RA treatment.

Abstract

Osteoarthritis (OA) is a progressive degenerative joint disease characterized by cartilage destruction and impaired intrinsic repair capacity. Here, we developed a cartilage-targeted delivery system by engineering human umbilical cord mesenchymal stem cells (hUC-MSCs) to co-express LGR5 and a cartilage affinity peptide (CAP), generating LGR5-engineered CAP-exosomes (CAP/LGR5-EXO), which were subsequently encapsulated within hyaluronic acid methacrylate (HAMA) hydrogel microspheres to enhance intra-articular retention. In vitro, CAP/LGR5-EXO promoted chondrocyte proliferation, enhanced extracellular matrix synthesis, and suppressed catabolic mediators, while also restoring mitochondrial homeostasis and relieving p21-driven cell cycle arrest. Bulk RNA-seq revealed that CAP/LGR5-EXO activated pathways related to cell cycle progression, mitochondrial protection, and oxidative stress resistance, as further supported by integrative analyses of three independent single-cell RNA-seq datasets. In vivo, CAP/LGR5-EXO@HMs exhibited prolonged joint retention, facilitated cartilage regeneration, reduced osteophyte formation, and significantly improved OARSI scores in a destabilization of the medial meniscus (DMM) mouse model. Collectively, our findings demonstrate that cartilage-targeted HAMA microspheres delivering LGR5-engineered exosomes effectively restore chondrocyte function and ameliorate OA progression, providing a promising therapeutic strategy for cartilage regeneration and OA treatment.

Abstract

Enhancing antibody exposure within the central nervous system (CNS) is critical for developing therapeutic monoclonal antibodies (Mabs) to treat CNS disorders. However, limited antibody penetration across the blood-brain barrier (BBB) and rapid efflux from the cerebrospinal fluid hinder effective CNS delivery. While most research efforts focus on enhancing the permeation of antibodies across the BBB, here we present an alternative strategy to enhance antibody retention by directly binding hyaluronic acid (HA) in the brain's extracellular space. To accomplish this, we fused the G1 domain of versican (VG1), a proteoglycan known for HA binding, with nontargeting Fab and Mab (IgG) antibodies. Using single-photon emission computed tomography/X-ray computed tomography imaging, we tracked the biodistribution of 125I-labeled Fab- and Mab-(VG1)2 fusion constructs, as well as their parent antibodies, after direct infusion into the lateral ventricles of cannulated mice. Over 96 h, both VG1 constructs significantly enhanced antibody exposure in the brain and spine compared to the parent antibodies. Fab-VG1 exhibited a more widespread brain distribution, while Mab-(VG1)2 was localized around the administration site. Fluorescence microscopy demonstrated periventricular distribution of antibody with a greater depth of infiltration for Fab-VG1 across all ventricles at 1 and 96 h time points compared to Mab-(VG1)2. Escalating the dose of Fab-VG1 enhanced tissue penetration distance. These findings demonstrate the feasibility of using HA-binding technology to enhance antibody exposure in the CNS, offering potential for the development of more effective antibody-based therapies for CNS disorders.

Abstract

This protocol outlines the fabrication and application of dissolvable microneedle (MN) patches containing α-lactalbumin nanomicelles for the targeted transdermal delivery of capsaicin to adipose tissue. The process begins with the partial enzymatic hydrolysis of α-lactalbumin, resulting in amphiphilic peptides that self-assemble into nanomicelles encapsulating the hydrophobic compound capsaicin. The capsaicin-loaded nanomicelles are mixed with a hyaluronic acid (HA) and polyvinyl alcohol (PVA) matrix, cast into polydimethylsiloxane (PDMS) molds, and centrifuged to produce 10 × 10 MN arrays. After vacuum drying, the MNs exhibit adequate mechanical strength for skin penetration and dissolve within approximately 30 min of application. Representative results include scanning electron microscopy, which confirms uniform morphology of MNs, confocal microscopy, which verifies skin penetration and drug release, and in vivo experiments in high-fat diet (HFD) mice showing reduced fat mass, enhanced metabolic activity, and induction of adipose browning. This protocol provides a reproducible and minimally invasive method for the transdermal delivery of hydrophobic bioactives, offering a promising therapeutic approach for the management of obesity. This protocol is optimized for reproducibility and is suitable for adaptation to other hydrophobic bioactives.

Abstract

Fibrotic diseases, which impair tissue function and contribute to organ failure, remain a major clinical challenge with limited treatment options. Mesenchymal stromal cells (MSCs) offer promise for antifibrotic therapy via paracrine signaling, but their clinical efficacy is hindered by poor survival and limited functional activity after transplantation. Here, we present a cell surface engineering strategy that reprograms the antifibrotic function of MSCs by constructing a pseudofibrotic extracellular matrix (ECM) on their surface. Through in situ self-assembly of peptide-modified hyaluronic acid, we generate a nanofiber-based matrix that mimics the dense, disordered architecture of fibrotic ECM. This matrix activates the Piezo1/PI3K-Akt signaling pathway, inducing up-regulation of Mmp13-a key collagen-degrading matrix metalloproteinase-in engineered MSCs. In a rat model of myocardial infarction-associated fibrosis, engineered MSCs exhibit robust antifibrotic activity compared to unmodified MSCs. These findings establish a bioinspired strategy for MSC reprogramming and offer a path toward more effective cell-based therapies for fibrotic disease.

Abstract

Photoaging of the skin, driven by ultraviolet B (UVB) radiation, is characterized by the upregulation of matrix metalloproteinases (MMPs), accelerated collagen degradation, diminished hyaluronic acid (HA) content, and disruption of extracellular matrix (ECM) integrity, culminating in wrinkle formation, and structural damage. Nutritional and plant-derived compounds have garnered increasing attention as promising therapeutic agents for skin aging. In this study, we explored the anti-photoaging effects of Gynostemma pentaphyllum hydrodistillate (GPHD) and its bioactive constituent, Damulin B, in UVB-irradiated in vivo and in vitro models. In HR-1 hairless mice, GPHD treatment significantly ameliorated UVB-induced wrinkle formation, collagen degradation, epidermal hyperplasia, and transepidermal water loss, while improving hydration and elasticity. It also modulated hyaluronic acid metabolism by upregulating hyaluronic acid synthases (HAS1 and HAS2) and downregulating hyaluronidases (HYAL1 and HYAL2). In UVB-irradiated Hs68 fibroblasts, GPHD and Damulin B attenuated reactive oxygen species (ROS) generation, thereby inhibiting mitogen-activated protein kinase/activator protein-1 (MAPK/AP-1) signaling and restoring transforming growth factor-beta/Smad (TGF-β/Smad) activity, ultimately contributing to ECM stability. Collectively, our findings demonstrate that GPHD and Damulin B exert potent anti-photoaging effects by mitigating oxidative stress and orchestrating downstream signaling pathways essential for ECM remodeling and skin homeostasis.

Abstract

Bacterial biofilm and intensive inflammation remain great challenge for wound healing. Herein, a multifunctional hydrogel based on gelatin methacryloyl (GelMA) was designed for wound dressing. The mechanical properties of GelMA hydrogel were improved by additional crosslinking with hyaluronic acid aldehyde (HA-CHO), with the compressive modulus were increased over two-fold. Polydopamine-coated cerium dioxide (PDA-CeO2) was loaded into GH hydrogel to enhance its antibacterial properties. Under near-infrared light (NIR) irradiation, the temperature increased by nearly 53 °C, consequently achieving an inhibition rate of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) exceeding 90%. Meanwhile, PDA-CeO2 could efficiently scavenge reactive oxygen species (ROS) and expression of hypoxia-inducible factor-1α (HIF-1α) was suppressed, polarizing macrophages from pro-inflammation M1 to anti-inflammation M2. The expression of M1 biomarker tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) was down-regulated nearly three- and five-fold respectively, while the expression of M2 biomarker transforming growth factor-β (TGF-β) and IL-10 was up-regulated over three-fold. Angiogenesis in human umbilical vein endothelial cell (HUVEC) was also enhanced. Besides, 3,4-dihydroxyphenylalanine grafted-fibroblast growth factor receptor-agonistic peptide (DOPA-FAP) was also integrated. It significantly improved fibroblast attachment and elevated the expression of collagen-I (COLI) over three-fold. In vivo experiment manifested the therapeutic effect of GH/DOPA-FAP/PDA-CeO2 hydrogel combining with NIR treatment. On the 15th day, the wound healing rate in infected wounds exceeded 95%. In conclusion, this study presented a smart strategy for wound healing that utilizes the photothermal antibacterial effect and remodels the immune microenvironment.

Abstract

Dermocosmetics are widely used to complement dermatologic care, yet context-specific guidance remains limited for populations with Fitzpatrick skin types III-V. We convened a national expert panel to generate transparent, reproducible recommendations across ten common clinical scenarios.

Abstract

Liver fibrosis is a dynamic and potentially reversible process until irreversible structural changes occur. This study evaluated the curative effect of crocin on carbon tetrachloride (CCl₄)-induced hepatic fibrosis in rats and explored the underlying mechanisms.

Abstract

Fibroblast growth factor 23 (FGF23) is a clinically significant protein hormone regulating phosphate and vitamin D metabolism, with elevated levels linked to chronic kidney disease, cardiovascular disorders, and impaired bone homeostasis. Despite its relevance as both a biomarker and a therapeutic target, its interactions with functional biomaterials remain poorly understood. In this work, we investigate the FGF23 adsorption on polyelectrolyte layers using a combination of theoretical modeling and experimental methods. Theoretical calculations provided insights into the protein's charge distribution and diffusion properties, while experimental measurements quantified its hydrodynamic diameter, electrophoretic mobility, and electrokinetic charge over a broad range of pH values. Microscale thermophoresis revealed quantitative binding affinities of FGF23 to hyaluronic acid, chitosan, and poly(diallyldimethylammonium chloride). Adsorption studies on mica, silica, and polyelectrolyte mono- and bilayers showed that FGF23 binds to both negatively and positively charged substrates, with binding affinities following: hyaluronic acid < poly(diallyldimethylammonium chloride) < chitosan. Desorption occurred more readily from negatively charged surfaces (mica, silica and hyaluronic acid), indicating weaker interactions compared to positively charged layers. These results reveal fundamental aspects of protein -polyelectrolyte interactions and highlight the reversible binding capacity of FGF23 to negatively charged surfaces. Such adsorption behavior provides a physicochemical framework for considering FGF23-polyelectrolyte systems in the design of therapeutic carriers and bioactive materials. However, any direct relevance to wound healing, chronic kidney disease, or cardiovascular disorders remains prospective and requires dedicated biological validation.