Functions of hyaluronan in wound repair

Recent advances in the adjunctive management of diabetic foot ulcer: Focus on noninvasive technologies

Diabetic foot ulcer (DFU) is one of the most costly and serious complications of diabetes. Treatment of DFU is usually challenging and new approaches are required to improve the therapeutic efficiencies. This review aims to update new and upcoming adjunctive therapies with noninvasive characterization for DFU, focusing on bioactive dressings, bioengineered tissues, mesenchymal stem cell (MSC) based therapy, platelet and cytokine-based therapy, topical oxygen therapy, and some repurposed drugs such as hypoglycemic agents, blood pressure medications, phenytoin, vitamins, and magnesium. Although the mentioned therapies may contribute to the improvement of DFU to a certain extent, most of the evidence come from clinical trials with small sample size and inconsistent selections of DFU patients. Further studies with high design quality and adequate sample sizes are necessitated. In addition, no single approach would completely correct the complex pathogenesis of DFU. Reasonable selection and combination of these techniques should be considered.

The efficacy of hyaluronic acid fragments with amino acid in combating facial skin aging: an ultrasound and histological study

BACKGROUND

Various techniques have been employed in aesthetic medicine to combat skin aging, in particular that of the facial region. Hyaluronic acid is utilized to enhance moisture levels and extracellular matrix molecules. This study aims to histologically assess the effects of low molecular weight hyaluronic acid fragments combined with amino acids (HAAM) on facial skin rejuvenation through intradermal microinjections.

METHODS

A total of twenty women, with an average age of 45 and ranging from 35 to 64 years old, participated in the study, including 8 in menopause and 12 in the childbearing age group. Mesotherapy was used to administer HAAM to the patients. Prior to and three months after the treatment, each patient underwent small circular punch biopsies. Ultrasound examinations were conducted using B-mode, capturing 2D images in longitudinal or transverse orientations with frequencies ranging from 5 to 13 Mega-hertz (MY LAB X8, ESAOTE, Genova, Italy). A total of 60 ultrasound examinations were taken, with 30 collected before treatment and 30 after treatment.

RESULTS

The histological analysis demonstrates an increase in fibroblast activity resulting in the production of Type III reticular collagen, as well as an increased number of blood vessels and epidermal thickness. However, the analysis of ultrasound data before and after treatment showed no statistical difference in skin thickness in malar area, chin and mandibular angle.

CONCLUSIONS

Histological assessments indicate that subcutaneous infiltration of HAAM has a substantial impact on the dermis of facial skin.

A multifunctional silk-hyaluronic acid self-healing hydrogel laden with alternatively activated macrophage-derived exosomes reshape microenvironment of diabetic wound and accelerate healing

The impairment of phenotype switching of pro-inflammatory M1 to pro-healing M2 macrophage induced by hyperglycemic microenvironment often elevates oxidative stress, impairs angiogenesis, and leads to chronic non-healing wounds in diabetic patients. Administration of M2 macrophage-derived exosomes (M2Exo) at wound site is known to polarize M1 to M2 macrophage and can accelerate wound healing by enhancing collagen deposition, angiogenesis, and re-epithelialization. In the present study, M2Exo were conjugated with oxidized hyaluronic acid and mixed with PEGylated silk fibroin to develop self-healing Exo-gel to achieve an efficient therapy for diabetic wounds. Exo-gel depicted porous networked morphology with self-healing and excellent water retention behaviour. Fibroblast cells treated with Exo-gel showed significant uptake of M2Exo that increased their proliferation and migration in vitro. Interestingly, in a diabetic wound model of wistar rats, Exo-gel treatment induced 75 % wound closure within 7 days with complete epithelial layer regeneration by modulating cytokine levels, stimulating fibroblast-keratinocyte interaction and migration, angiogenesis, and organized collagen deposition. Taken together, this study suggests that Exo-gel depict properties of an excellent wound healing matrix and can be used as a therapeutic alternative to treat chronic non-healing diabetic wounds.

Adjunctive use of hyaluronic acid in the treatment of gingival recessions: a systematic review and meta-analysis

OBJECTIVES

To explore the efficacy of Hyaluronic acid as an adjunctive in treatment of gingival recessions (GR).

MATERIALS AND METHODS

A systematic literature search was performed in several electronic databases, including Medline/ PubMed, Embase, CENTRAL and LILACS. Recession improvement was evaluated through multiple outcome variables. The Cochrane Risk of Bias tool and the ROBINS-I tool were used to assess the quality of the included trials. Weighted Mean Differences (WMDs) and 95% confidence intervals (CIs) between test and control sites were estimated through meta-analysis using a random-effect model for the amount of Relative Root Coverage (RRC).

RESULTS

A total of 3 randomised studies were deemed as eligible for inclusion. Their data were also used for pooling the effect estimates. Overall analysis of RRC (3 studies) presented a WMD of 7.49% (p = 0.42; 95% CIs -10.88, 25.86) in favour of adjunctive use of hyaluronic acid during Coronally Advanced Flap (CAF) technique, although statistical significance was not reached. Statistical heterogeneity was found to be high (I2 = 80%).

CONCLUSIONS

Within their limitations, the present data indicate that the local application of Hyaluronic acid does not lead to additional clinical benefits when used as an adjunctive to the treatment of GR with CAF. However, due to the high heterogeneity among the studies, additional well-designed RCTs are needed to provide further evidence on this clinical indication for the use of Hyaluronic acid.

CLINICAL RELEVANCE

In the frame of the current review, the adjunctive use of Hyaluronic acid does not additionally improve the clinical outcomes obtained during treatment of GR with CAF.

Healing of Periodontal Suprabony Defects following Treatment with Open Flap Debridement with or without Hyaluronic Acid (HA) Application

Background and Objectives: This randomized, double-arm, multicentric clinical trial aims to compare the clinical outcomes following the treatment of suprabony periodontal defects using open flap debridement (OFD) with or without the application of hyaluronic acid (HA). Materials and Methods: Sixty systemically healthy patients with at least two teeth presenting suprabony periodontal defects were randomly assigned with a 1:1 allocation ratio using computer-generated tables into a test (OFD + HA) or control group (OFD). The main outcome variable was clinical attachment level (CAL). The secondary outcome variables were changes in mean probing pocket depth (PPD), gingival recession (GR), full-mouth plaque score (FMPS), and full-mouth bleeding score (FMBS). All clinical measurements were carried out at baseline and 12 months. Results: Sixty patients, thirty in each group, were available for statistical analysis. The mean CAL gain was statistically significantly different (p < 0.001) in the test group compared with the control group (3.06 ± 1.13 mm vs. 1.44 ± 1.07 mm). PPD reduction of test group measurements (3.28 ± 1.14 mm) versus the control group measurements (2.61 ± 1.22 mm) were statistically significant (p = 0.032). GR changes were statistically significant only in the test group 0.74 ± 1.03 mm (p < 0.001). FMBS and FMPS revealed a statistically significant improvement mostly in the test group. Conclusions: Suprabony periodontal defects could benefit from the additional application of HA in conjunction with OFD in terms of improvement of the clinical parameters compared with OFD alone.

Strategies to improve the performance of polyetheretherketone (PEEK) as orthopedic implants: from surface modification to addition of bioactive materials

Polyetheretherketone (PEEK), as a high-performance polymer, is widely used for bone defect repair due to its homogeneous modulus of elasticity of human bone, good biocompatibility, excellent chemical stability and projectability. However, the highly hydrophobic surface of PEEK is biologically inert, which makes it difficult for cells and proteins to attach, and is accompanied by the development of infections that ultimately lead to failure of PEEK implants. In order to further enhance the potential of PEEK as an orthopedic implant, researchers have explored modification methods such as surface modification by physical and chemical means and the addition of bioactive substances to PEEK-based materials to enhance the mechanical properties, osteogenic activity and antimicrobial properties of PEEK. However, these current modification methods still have obvious shortcomings in terms of cost, maneuverability, stability and cytotoxicity, which still need to be explored by researchers. This paper reviews some of the modification methods that have been used to improve the performance of PEEK over the last three years in anticipation of the need for researchers to design PEEK orthopedic implants that better meet clinical needs.

Application of hydrogel microneedles in the oral cavity

Microneedles are a transdermal drug delivery system in which the needle punctures the epithelium to deliver the drug directly to deep tissues, thus avoiding the influence of the first-pass effect of the gastrointestinal tract and minimizing the likelihood of pain induction. Hydrogel microneedles are microneedles prepared from hydrogels that have good biocompatibility, controllable mechanical properties, and controllable drug release and can be modified to achieve environmental control of drug release in vivo. The large epithelial tissue in the oral cavity is an ideal site for drug delivery via microneedles. Hydrogel microneedles can overcome mucosal hindrances to delivering drugs to deep tissues; this prevents humidity and a highly dynamic environment in the oral cavity from influencing the efficacy of the drugs and enables them to obtain better therapeutic effects. This article analyzes the materials and advantages of common hydrogel microneedles and reviews the application of hydrogel microneedles in the oral cavity.

The significant role of glycosaminoglycans in tooth development

This review delves into the roles of glycosaminoglycans (GAGs), integral components of proteoglycans, in tooth development. Proteoglycans consist of a core protein linked to GAG chains, comprised of repeating disaccharide units. GAGs are classified into several types, such as hyaluronic acid, heparan sulfate, chondroitin sulfate, dermatan sulfate, and keratan sulfate. Functioning as critical macromolecular components within the dental basement membrane, these GAGs facilitate cell adhesion and aggregation, and play key roles in regulating cell proliferation and differentiation, thereby significantly influencing tooth morphogenesis. Notably, our recent research has identified the hyaluronan-degrading enzyme Transmembrane protein 2 (Tmem2) and we have conducted functional analyses using mouse models. These studies have unveiled the essential role of Tmem2-mediated hyaluronan degradation and its involvement in hyaluronan-mediated cell adhesion during tooth formation. This review provides a comprehensive summary of the current understanding of GAG functions in tooth development, integrating insights from recent research, and discusses future directions in this field.

Hyaluronic acid from bluefin tuna by-product: Structural analysis and pharmacological activities

The fishing and aquaculture industries generate a huge amount of waste during processing and preservation operations, especially those of tuna. Recovering these by-products is a major economic and environmental challenge for manufacturers seeking to produce new active biomolecules of interest. A new hyaluronic acid was extracted from bluefin tuna's vitreous humour to assess its antioxidant and pharmacological activities. The characterization by infrared spectroscopy (FT-IR), nuclear magnetic resonance ((1D1H) and 2D (1H COSY, 1H/13C HSQC)) and size exclusion chromatography (SEC/MALS/DRI/VD) revealed that the extracted polysaccharide was a hyaluronic acid with high uronic acid content (55.8 %) and a weight average molecular weight of 888 kDa. This polymer possesses significant anti-radical activity and ferrous chelating capacity. In addition, pharmacological evaluation of its anti-inflammatory and analgesic potential, using preclinical models, in comparison with reference drugs (Dexamethasone, diclofenac, and acetylsalicylate of lysine), revealed promising anti-inflammatory activity as well as interesting peripheral and central antinociceptive activity. Therefore, our new hyaluronic acid compound may therefore serve as a potential drug candidate for the treatment of pain sensation and inflammation of various pathological origins.

Hyaluronic acid in Dentoalveolar regeneration: Biological rationale and clinical applications

Background

Hyaluronic acid (HA) is found in different locations in the periodontium, including mineralized tissues (i.e., cementum and alveolar bone) and non-mineralized tissues (i.e., gingiva and periodontal ligament). In addition, it seems to play an essential part in regulating the underlying mechanisms involved in tissue inflammatory reactions and wound healing. HA has the potential to regulate periodontal tissue regeneration and treat periodontal disease.

Aim

The current review of the literature was conducted to assess how HA plays its part in periodontal therapy and examine the contemporary literature's viewpoint on its use in periodontal regeneration.

Conclusion

HA has a multifunctional character in periodontal regeneration, and healing and appears to provide promising outcomes in different periodontal regenerative applications.

Multifunctional Wound Curation Dressing Material FemuFrost─An Antioxidant-Loaded Nanoemulsion Frosted Patch of Poly(vinyl alcohol) and Hyaluronic Acid

The wound curation dressing material should own explicit elements to aggrandize wound cessation. The cryogel of poly(vinyl alcohol) (PVA) and hyaluronic acid (HA) is deemed to promote the angiogenesis, production of extracellular matrix components, granulation, and epithelialization. The research aims to tailor and evaluate the composite PVA/HA cryogel ingrained ferulic acid-loaded nanoemulsion patch labeled as PH-FemuFrost to improve the therapeutic properties and mechanical strength of the patches. The PH-FemuFrost exhibited a water uptake capacity of 268 ± 15.07%, porosity of 70.52 ± 7.4%, and 48.62 ± 2.2% in vitro degradation. The texture analysis revealed the improved mechanical properties of PH-FemuFrost in terms of burst strength and stiffness. The PH-FemuFrost exhibited in vitro antioxidant and antimicrobial activity against Staphylococcus aureus and Candida albicans species. The wound healing efficiency of PH-FemuFrost patches was significantly increased than blank PVA-HA patches. The groups treated with PH-FemuFrost exhibited a dense network of collagen type 1 in comparison to negative and PVA-HA groups. The normal skin and healed skin exhibited parallel arrangement of type I collagen fibers toward the skin. The levels of inflammatory mediators such as IL-6 (p value < 0.0001), IL-22 (p value 0.0098), and TNF-α levels (p value < 0.0001) of PH-FemuFrost is significantly reduced compared to the negative group.

Novel PVA-Hyaluronan-Siloxane Hybrid Nanofiber Mats for Bone Tissue Engineering

Hyaluronan (HA) is a natural biodegradable biopolymer; its biological functions include cell adhesion, cell proliferation, and differentiation as well as decreasing inflammation, angiogenesis, and regeneration of damaged tissue. This makes it a suitable candidate for fabricating nanomaterials with potential use in tissue engineering. However, HA nanofiber production is restricted due to the high viscosity, low evaporation rate, and high surface tension of HA solutions. Here, hybrids in the form of continuous and randomly aligned polyvinyl alcohol (PVA)-(HA)-siloxane nanofibers were obtained using an electrospinning process. PVA-HA fibers were crosslinked by a 3D siloxane organic-inorganic matrix via sol-gel that restricts natural hydrophilicity and stiffens the structure. The hybrid nanofiber mats were characterized by FT-IR, micro-Raman spectroscopy, SEM, and biological properties. The PVA/HA ratio influenced the morphology of the hybrid nanofibers. Nanofibers with high PVA content (10PVA-8 and 10PVA-10) form mats with few beaded nanofibers, while those with high HA content (5PVA-8 and 5PVA-10) exhibit mats with mound patterns formed by "ribbon-like" nanofibers. The hybrid nanofibers were used as mats to support osteoblast growth, and they showed outstanding biological properties supporting cell adhesion, cell proliferation, and cell differentiation. Importantly, the 5PVA-8 mats show 3D spherical osteoblast morphology; this suggests the formation of tissue growth. These novel HA-based nanomaterials represent a relevant advance in designing nanofibers with unique properties for potential tissue regeneration.

Hyaluronic acid enhances cell migration, viability, and mineralized tissue-specific genes in cementoblasts

BACKGROUND/OBJECTIVES

It has been repeatedly demonstrated that cementum formation is a crucial step in periodontal regeneration. Hyaluronic acid (HA) is an important component of the extracellular matrix which regulates cells functions and cell-cell communication. Hyaluronic acid/derivatives have been used in regenerative periodontal therapy, but the cellular effects of HA are still unknown. To investigate the effects of HA on cementoblast functions, cell viability, migration, mineralization, differentiation, and mineralized tissue-associated genes and cementoblast-specific markers of the cementoblasts were tested.

MATERIALS AND METHODS

Cementoblasts (OCCM-30) were treated with various dilutions (0, 1:2, 1:4, 1:8, 1:16, 1:32, 1:64, 1:128) of HA and examined for cell viability, migration, mineralization, and gene expressions. The mRNA expressions of osteocalcin (OCN), runt-related transcription factor 2 (Runx2), bone sialoprotein (BSP), collagen type I (COL-I), alkaline phosphatase (ALP), cementum protein-1 (CEMP-1), cementum attachment protein (CAP), and small mothers against decapentaplegic (Smad) -1, 2, 3, 6, 7, β-catenin (Ctnnb1) were performed with real-time polymerase chain reaction (RT-PCR). Total RNA was isolated on days 3 and 8, and cell viability was determined using MTT assay on days 1 and 3. The cell mineralization was evaluated by von Kossa staining on day 8. Cell migration was assessed 2, 4, 6, and 24 hours following exposure to HA dilutions using an in vitro wound healing assay (0, 1:2, 1:4, 1:8).

RESULTS

At dilution of 1:2 to 1:128, HA importantly increased cell viability (p < .01). HA at a dilution of 1/2 increased wound healing rates after 4 h compared to the other dilutions and the untreated control group. Increased numbers of mineralized nodules were determined at dilutions of 1:2, 1:4, and 1:8 compared with control group. mRNA expressions of mineralized tissue marker including COL-I, BSP, RunX2, ALP, and OCN significantly improved by HA treatments compared with control group both on 3 days and on 8 days (p < .01). Smad 2, Smad 3, Smad 7, and β-catenin (Ctnnb1) mRNAs were up-regulated, while Smad1 and Smad 6 were not affected by HA administration. Additionally, HA at dilutions of 1:2, 1:4, and 1:8 remarkably enhanced CEMP-1 and CAP expressions in a dilution- and time-dependent manner (p < .01).

CONCLUSIONS

The present results have demonstrated that HA affected the expression of both mineralized tissue markers and cementoblast-specific genes. Positive effects of HA on the cementoblast functions demonstrated that HA application may play a key role in cementum regeneration.

Self-Adhesive, Strong Antifouling, and Mechanically Reinforced Methacrylate Hyaluronic Acid Cross-Linked Carboxybetaine Zwitterionic Hydrogels

Hyaluronic acid and zwitterionic hydrogels are soft materials with poor mechanical properties. The unique structures and physiological properties make them attractive candidates for ideal hydrogel dressings, but the crux of lacking satisfying mechanical strengths and adhesive properties is still pendent. In this study, the physical cross-linking of dipole-dipole interactions of zwitterionic pairs was utilized to enhance the mechanical properties of hydrogels. The hydrogels have been prepared by copolymerizing methacrylate hyaluronic (HAGMA) with carboxybetaine methacrylamide (CBMAA) (the mass ratio of [HAGMA]/[CBMAA] is 2:5, 1:5, 1:10, or 1:20), obtaining HA-CB2.5, HA-CB5.0, HA-CB10.0, or HA-CB20.0 hydrogel. Therein, the HA-CB20.0 hydrogel with a high CBMAA content can generate a strong dipole-dipole interaction to form internal physical cross-links, exhibit stretchability and low elastic modulus, and withstand 99% compressive deformation and cyclic compression under strain at 90%. Moreover, the HA-CB20.0 hydrogel is adhesive to diverse substrates, including skin, glass, stainless steel, and plastic. The synergistic effect of HAGMA and CBMAA shows strong anti-biofouling, high water absorption, biodegradability under hyaluronidase, and biocompatibility.

Comparative In Vivo Study of Solid-Type Pure Hyaluronic Acid in Thread Form: Safety and Efficacy Compared to Hyaluronic Acid Filler and Polydioxanone Threads

INTRODUCTION

Although various products are commonly used for skin rejuvenation, solid-type hyaluronic acid (HA) as an injectable form has not been researched or utilized. This study aimed to demonstrate the safety and efficacy of solid-type HA in thread form, which differs from the conventional gel-type HA commonly used.

METHOD

Solid-type HA threads, conventional HA fillers, and polydioxanone (PDO) threads were inserted into the dorsal subcutaneous layer of mice. Photographs were taken on days 0, 1, 3, and 7, and on day 7, the samples were harvested for histological analysis. Inflammatory reactions and detection of collagen were confirmed through tissue staining, and real-time PCR was conducted to quantify collagen synthesis.

RESULTS

In the histological analysis, the PDO threads exhibited a greater inflammatory response compared to the HA threads. Masson's trichrome staining revealed a higher degree of collagen synthesis in the HA thread group compared to the HA filler group. While collagen type 1 expression was significantly higher in the PDO thread group than in the HA thread group, the HA thread group showed higher expression levels of collagen type 3. Furthermore, the PDO thread group demonstrated a statistically significant increase in TGF-β1 compared to the HA group.

CONCLUSION

This in vivo study demonstrated the stable application of solid-type pure HA threads and their potential for inducing collagen production, while also yielding a low inflammatory response. The findings highlight the promising applications of solid-type HA in the field of cosmetic dermatology.

NO LEVEL ASSIGNED

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Factors affecting the healing of decubital lesions in patients wearing newly made dentures

Background/purpose

Decubital lesions or traumatic ulcers caused by dentures usually appear one or two day(s) after new dentures placement due to mismatch of the microrelief of the tissue and the microrelief of the gingival surface of the prosthesis. The study aimed to analyze factors that could influence the healing of ulcers during a one-week period after the placement of new partial and complete dentures.

Materials and methods

The prospective cohort study included 60 patients with new denture-induced traumatic ulcers. Traumatic ulcers were treated with denture adjustment, or combination of adjustment with 0.2% or 0.3% hyaluronic acid gels respectively for seven days. Healing of ulcers were observed through measurement of perimeter, area, maximum and minimum diameters on digital photographs. Multivariate logistic regression was used to predict other factors that could affect healing process.

Results

Perimeter, area, maximum and minimum diameters of denture-related ulcers were significant decreased after application of gels on the fifth and seventh day. The fifth day ulcers were not healed if dentures were only adjusted, while healed lesion was 40% for the other two groups. On the seventh day, the percent of healed lesion in the group with dentures adjustment was 20%, while it was increased to 75% healed lesions for combination of denture adjustment and hyaluronic acid gels. Anticoagulant/anti-aggregation drugs also had positive impact on ulcer healing; antihypertensives that included diuretics slowed ulcer healing, other monitored factors in the study did not show a significant impact.

Conclusion

Hyaluronic acid in combination with the dentures adjustment for seven days leads to higher healing rate, and reduction in size of ulcers that did not heal until this time point.

Stem cell-derived small extracellular vesicles embedded into methacrylated hyaluronic acid wound dressings accelerate wound repair in a pressure model of diabetic ulcer

Over the past years, the development of innovative smart wound dressings is revolutionizing wound care management and research. Specifically, in the treatment of diabetic foot wounds, three-dimensional (3D) bioprinted patches may enable personalized medicine therapies. In the present work, a methacrylated hyaluronic acid (MeHA) bioink is employed to manufacture 3D printed patches to deliver small extracellular vesicles (sEVs) obtained from human mesenchymal stem cells (MSC-sEVs). The production of sEVs is maximized culturing MSCs in bioreactor. A series of in vitro analyses are carried out to demonstrate the influence of MSC-sEVs on functions of dermal fibroblasts and endothelial cells, which are the primary functional cells in skin repair process. Results demonstrate that both cell populations are able to internalize MSC-sEVs and that the exposure to sEVs stimulates proliferation and migration. In vivo experiments in a well-established diabetic mouse model of pressure ulcer confirm the regenerative properties of MSC-sEVs. The MeHA patch enhances the effectiveness of sEVs by enabling controlled release of MSC-sEVs over 7 days, which improve wound epithelialization, angiogenesis and innervation. The overall findings highlight that MSC-sEVs loading in 3D printed biomaterials represents a powerful technique, which can improve the translational potential of parental stem cell in terms of regulatory and economic impact.

Use of hyaluronic acid matrix in dorsal augmentation rhinoplasty

Augmentation rhinoplasty sometimes is required for patients with saddle nose deformity caused by failed rhinoplasty or facial trauma; finding appropriate grafting material remains a significant problem for this procedure. We investigated hyaluronic acid matrix as an allograft for dorsal augmentation rhinoplasty in a rabbit model. We performed an osteotomy on the nasal bones of eight rabbits. Four animals were sham operated as the control group and four were administered a mixture of saline-gelled hyaluronic acid matrix and sliced cartilage. Ultrasonography and three-dimensional reconstruction tomography were performed at the end of the experimental period. After sacrifice of the animals, nasal tissues were examined for histopathology, and both collagen scores and number of capillaries were compared between the two groups. Increased collagen and capillaries were apparent in the hyaluronic acid matrix group compared to controls. The median collagen score was significantly greater for the hyaluronic acid matrix group than for the control group. Although the number of capillaries for the hyaluronic acid matrix group was greater than for the control group, the difference was not statistically significant. Three weeks is sufficient for adhesion of ends of fractures in clinical practice; however, we found no ossification at this time in either group. A hyaluronic acid matrix may be a useful alternative supplement for dorsal augmentation rhinoplasty. Development of collagen was commensurate with membranous ossification; however, assessment of complete ossification requires a longer experimental period.

Xioglican Cream in Italian Patients with Chronic Venous Disease: A Post-Marketing Study Investigating Effects on Clinical and Cutaneous Signs and Symptoms

INTRODUCTION

The progression of chronic venous disease (CVD) is characterized by edema of the legs and/or venous ulcers of the lower limbs in association with cutaneous signs and/or skin alterations, such as hyperpigmentation, corona phlebectatica, telangiectasia, eczematous dermatitis, lipodermatosclerosis, atrophie blanche, cellulitis, and induration. Xioglican cream is a galactosaminoglycan polysulfate and hyaluronic acid-containing medical device with strong hydrophilic, moisturizing, and soothing properties. This post-marketing observational study evaluated topical Xioglican cream in the amelioration of skin manifestations and clinical signs and symptoms in patients with CVD treated in routine clinical practice.

METHODS

Adult patients (18-75 years) with a clinical diagnosis of C2-C3 CVD according to Clinical, Etiology, Anatomy, and Pathophysiology (CEAP) classification who received 12 weeks of treatment with Xioglican (applied up to 3 times daily), according to investigator decision (and consistent with conventional clinical practice and established standard of care), were enrolled from two study sites in Italy. A range of endpoints were used to evaluate efficacy, safety, effect on patient quality of life (QoL), and patient satisfaction with topical application of Xioglican cream in the physiological restoration of skin signs and symptoms.

RESULTS

In patients with CVD (n = 30), Xioglican cream reduced CVD-related skin manifestations and associated symptoms, with significant reductions in leg circumference [mean ± standard deviation (SD): - 3.21 ± 3.39 cm for left and - 2.92 ± 2.70 cm for right legs, both p < 0.0001] and local edema (- 5.52 ± 7.94 cm, p = 0.0034) and significant improvement in Venous Clinical Severity Scores (mean 0.52 ± 1.94 decrease from baseline, p = 0.1952) observed after 12 weeks. Skin burning, pain, aching or tiredness, and QoL were also significantly improved. There was no change in CEAP classification. Globally, 92.0% of patients were "Very satisfied" or "Satisfied" with the product.

CONCLUSIONS

Topical treatment with Xioglican cream improves the signs, symptoms, and QoL of patients with CVD class C2-C3.

Randomized Clinical Trial of Topical Insulin Versus Artificial Tears for Healing Rates of Iatrogenic Corneal Epithelial Defects Induced During Vitreoretinal Surgery in Diabetics

PURPOSE

The aim of this study was to measure and compare the effect of topical insulin (0.5 units, 4 times per day) versus artificial tears (Vismed, sodium hyaluronate 0.18%, 4 times per day) for the healing of postoperative corneal epithelial defects induced during vitreoretinal surgery in diabetic patients.

METHODS

This is a double-blind randomized controlled hospital-based study involving diabetic patients with postoperative corneal epithelial defects after vitreoretinal surgery. Diabetic patients were randomized into 2 different groups and received either 0.5 units of topical insulin (DTI) or artificial tears (Vismed, sodium hyaluronate 0.18%; DAT). The primary outcome measured was the rate of corneal epithelial wound healing (mm 2 /h) over a preset interval and time from baseline to minimum size of epithelial defect on fluorescein-stained anterior segment digital camera photography. The secondary outcome measured was the safety of topical insulin 0.5 units and artificial tears (Vismed, sodium hyaluronate 0.18%). Patients were followed up until 3 months postoperation.

RESULTS

A total of 38 eyes from 38 patients undergoing intraoperative corneal debridement during vitreoretinal surgery with resultant epithelial defects (19 eyes per group) were analyzed. DTI was observed to have a significantly higher healing rate compared with the DAT group at rates over 36 hours ( P = 0.010), 48 hours ( P = 0.009), and 144 hours ( P = 0.009). The rate from baseline to closure was observed to be significantly higher in the DTI group (1.20 ± 0.29) (mm 2 /h) compared with the DAT group (0.78 ± 0.20) (mm 2 /h) as well ( P < 0.001). No adverse effect of topical insulin and artificial tears was reported.

CONCLUSIONS

Topical insulin (0.5 units, 4 times per day) is more effective compared with artificial tears (Vismed, sodium hyaluronate 0.18%, 4 times per day) for the healing of postoperative corneal epithelial defects induced during vitreoretinal surgery in diabetic patients, without any adverse events.

Types and doses of anti-adhesive agents injected into subacromial space do not have an effect on the clinical and anatomical outcomes after arthroscopic rotator cuff repair

PURPOSE

Joint stiffness after arthroscopic rotator cuff repair is a major concern for orthopaedic surgeons. Various antiadhesive agents are commonly administered after rotator cuff repair for its prevention. This study aimed to compare the outcomes among patients injected with different types and amounts of anti-adhesive agents after rotator cuff repair. It was hypothesized that the outcomes might differ depending on the use of the anti-adhesive agent and its type and dose.

METHODS

A total of 267 patients who underwent arthroscopic rotator cuff repair with or without subacromial injection of anti-adhesive agents were enrolled. The first group (group A; 51 patients) were injected with 3 mL of poloxamer/sodium alginate-based anti-adhesive agent. The second group (group B; 93 patients) were injected with 3 mL of sodium hyaluronate-based anti-adhesive agent. The third group (group C; 82 patients) were injected with 1.5 mL of sodium hyaluronate-based anti-adhesive agent. Finally, the last group (group D; 41 patients) who did not use anti-adhesive agents served as the control. The range of motion (ROM) and pain VAS scores were measured preoperatively and at 5 weeks, 3 months, 6 months, and 1 year postoperatively. Functional outcomes were evaluated using American Shoulder and Elbow Surgeons and Constant scores, whereas cuff integrity was assessed via MRI or ultrasonography at least 6 months postoperatively.

RESULTS

All ROM measurements, pain VAS scores, and functional scores were significantly improved regardless of the use, type, and dose of the anti-adhesive agents. In addition shoulder ROM and rotator cuff healing did not significantly differ among the groups (all n.s.).

CONCLUSIONS

No significant differences were found in the clinical and anatomical outcomes according to the type and dose of the anti-adhesive agents subacromially injected after rotator cuff repair.

LEVEL OF EVIDENCE

III.

Comparative analysis of platelet-rich fibrin membrane and 0.2% hyaluronic acid gel on healing following gingival depigmentation procedure

Introduction

Platelet-rich fibrin (PRF) accelerates wound healing by promoting faster cicatricial tissue remodeling and excellent neovascularization. Hyaluronic acid (HA) being biocompatible, anti-inflammatory, and proangiogenic leads to improvement in the rate of wound healing.

Aim

The aim of this study was to compare the effect of PRF membrane and 0.2% HA gel on wounds after gingival depigmentation surgery.

Materials and Methods

This study was carried out on 30 systemically healthy individuals recruited from the pool of patients who visited the department of periodontology. After depigmentation procedure in every patient, the sites were divided into three even groups. Group A received PRF membrane and periodontal dressing, Group B received 0.2% HA gel application and periodontal dressing, and Group C served as a control group in which only periodontal dressing was placed. The individuals were evaluated for the healing index (HI) and Numerical Rating Scale (NRS) on the 3rd and 5th day. Epithelialization test (ET) was performed on the 5th day. Gingival biotype was reassessed and compared to preoperative value after 3 months. The clinical trial was expressed in terms of mean and standard deviation. Intra-group comparison and inter-group comparison were done through the Kruskal-Wallis ANOVA test. All statistical tests were performed through SPSS version 25.0 (IBM).

Results

The inter-group statistical analysis concerning NRS, HI, and ET showed statistically significant results in Groups A and B compared to Group C (P < 0.05), while gingival biotype showed statistically significant results in Group A compared to Groups B and C.

Conclusion

The use of PRF membrane and HA gel to protect the raw wound site of depigmented gingiva proved to be an effective approach, resulting in faster healing.

Tmem2 Deficiency Leads to Enamel Hypoplasia and Soft Enamel in Mouse

Teeth consist of 3 mineralized tissues: enamel, dentin, and cementum. Tooth malformation, the most common craniofacial anomaly, arises from complex genetic and environmental factors affecting enamel structure, size, shape, and tooth eruption. Hyaluronic acid (HA), a primary extracellular matrix component, contributes to structural and physiological functions in periodontal tissue. Transmembrane protein 2 (TMEM2), a novel cell surface hyaluronidase, has been shown to play a critical role during embryogenesis. In this study, we demonstrate Tmem2 messenger RNA expression in inner enamel epithelium and presecretory, secretory, and mature ameloblasts. Tmem2 knock-in reporter mice reveal TMEM2 protein localization at the apical and basal ends of secretory ameloblasts. Micro-computed tomography analysis of epithelial-specific Tmem2 conditional knockout (Tmem2-CKO) mice shows a significant reduction in enamel layer thickness and severe enamel deficiency. Enamel matrix protein expression was remarkably downregulated in Tmem2-CKO mice. Scanning electron microscopy of enamel from Tmem2-CKO mice revealed an irregular enamel prism structure, while the microhardness and density of enamel were significantly reduced, indicating impaired ameloblast differentiation and enamel matrix mineralization. Histological evaluation indicated weak adhesion between cells and the basement membrane in Tmem2-CKO mice. The reduced and irregular expressions of vinculin and integrin β1 suggest that Tmem2 deficiency attenuated focal adhesion formation. In addition, abnormal HA accumulation in the ameloblast layer and weak claudin 1 immunoreactivity in Tmem2-CKO mice indicate impaired tight junction gate function. Irregular actin filament assembly was also observed at the apical and basal ends of secretory ameloblasts. Last, we demonstrated that Tmem2-deficient mHAT9d mouse ameloblasts exhibit defective adhesion to HA-containing substrates in vitro. Collectively, our data highlight the importance of TMEM2 in adhesion to HA-rich extracellular matrix, cell-to-cell adhesion, ameloblast differentiation, and enamel matrix mineralization.

Oral delivery of RNAi for cancer therapy

Cancer is a major health concern worldwide and is still in a continuous surge of seeking for effective treatments. Since the discovery of RNAi and their mechanism of action, it has shown promises in targeted therapy for various diseases including cancer. The ability of RNAi to selectively silence the carcinogenic gene makes them ideal as cancer therapeutics. Oral delivery is the ideal route of administration of drug administration because of its patients' compliance and convenience. However, orally administered RNAi, for instance, siRNA, must cross various extracellular and intracellular biological barriers before it reaches the site of action. It is very challenging and important to keep the siRNA stable until they reach to the targeted site. Harsh pH, thick mucus layer, and nuclease enzyme prevent siRNA to diffuse through the intestinal wall and thereby induce a therapeutic effect. After entering the cell, siRNA is subjected to lysosomal degradation. Over the years, various approaches have been taken into consideration to overcome these challenges for oral RNAi delivery. Therefore, understanding the challenges and recent development is crucial to offer a novel and advanced approach for oral RNAi delivery. Herein, we have summarized the delivery strategies for oral delivery RNAi and recent advancement towards the preclinical stages.

Skin Cell and Tissue Responses to Cross-Linked Hyaluronic Acid in Low-Grade Inflammatory Conditions

Hyaluronic acid (HA), used in a variety of medical applications, is associated in rare instances to long-term adverse effects. Although the aetiology of these events is unknown, a number of hypotheses have been proposed, including low molecular weight of HA (LMW-HA) in the filler products. We hypothesized that cross-linked HA and its degradation products, in a low-grade inflammatory microenvironment, could impact immune responses that could affect cell behaviours in the dermis. Using two different cross-linking technologies VYC-15L and HYC-24L+, and their hyaluronidase-induced degradation products, we observed for nondegraded HA, VYC-15L and HYC-24L+, a moderate and transient increase in IL-1β, TNF-α in M1 macrophages under low-grade inflammatory conditions. Endothelial cells and fibroblasts were preconditioned using inflammatory medium produced by M1 macrophages. 24 h after LMW-HA fragments and HA stimulation, no cytokine was released in these preconditioned cells. To further characterize HA responses, we used a novel in vivo murine model exhibiting a systemic low-grade inflammatory phenotype. The intradermal injection of VYC-15L and its degradation products induced an inflammation and cell infiltration into the skin that was more pronounced than those by HYC-24L+. This acute cutaneous inflammation was likely due to mechanical effects due to filler injection and tissue integration rather than its biological effects on inflammation. VYC-15L and its degradation product potentiated microvascular response to acetylcholine in the presence of a low-grade inflammation. The different responses with 2D cell models and mouse model using the two tested cross-linking HA technologies showed the importance to use integrative complex model to better understand the effects of HA products according to inflammatory state.

The Influence of κ-Carrageenan-R-Phycoerythrin Hydrogel on In Vitro Wound Healing and Biological Function

Wound healing is widely recognized as a critical issue impacting the healthcare sector in numerous countries. The application of wound dressings multiple times in such instances can result in tissue damage, thereby increasing the complexity of wound healing. With the aim of tackling this necessity, in the present study, we have formulated a hydrogel using natural polysaccharide κ-carrageenan and phycobiliprotein R-phycoerythrin from Pyropia yezoensis. The formulated hydrogel κ-Carrageenan-R-Phycoerythrin (κ-CRG-R-PE) was analyzed for its antioxidant and antimicrobial activity. The wound healing potential of the κ-CRG-R-PE was evaluated in Hs27 cells by the wound scratch assay method. The hydrogel showed dose-dependent antioxidant activity and significant antimicrobial activity at 100 μg/mL concentration. κ-CRG-R-PE hydrogels promoted more rapid and complete wound closure than κ-Carrageenan (κ-CRG) hydrogel at 24 and 48 h. κ-CRG-R-PE hydrogels also filled the wound within 48 h of incubation, indicating that they positively affect fibroblast migration and wound healing.

Dressings and topical agents containing hyaluronic acid for chronic wound healing

BACKGROUND

Hyaluronic acid is synthesised in plasma membranes and can be found in extracellular tissues. It has been suggested that the application of hyaluronic acid to chronic wounds may promote healing, and the mechanism may be due to its ability to maintain a moist wound environment which helps cell migration in the wound bed.

OBJECTIVES

To evaluate the effects of hyaluronic acid (and its derivatives) on the healing of chronic wounds.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was February 2022.

SELECTION CRITERIA

We included randomised controlled trials that compared the effects of hyaluronic acid (as a dressing or topical agent) with other dressings on the healing of pressure, venous, arterial, or mixed-aetiology ulcers and foot ulcers in people with diabetes.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 12 trials (13 articles) in a qualitative synthesis, and were able to combine data from four trials in a quantitative analysis. Overall, the included trials involved 1108 participants (mean age 69.60 years) presenting 178 pressure ulcers, 54 diabetic foot ulcers, and 896 leg ulcers. Sex was reported for 1022 participants (57.24% female). Pressure ulcers It is uncertain whether there is a difference in complete healing (risk ratio (RR) 1.17, 95% confidence interval (CI) 0.58 to 2.35); change in ulcer size (mean difference (MD) 25.60, 95% CI 6.18 to 45.02); or adverse events (none reported) between platelet-rich growth factor (PRGF) + hyaluronic acid and PRGF because the certainty of evidence is very low (1 trial, 65 participants). It is also uncertain whether there is a difference in complete healing between lysine hyaluronate and sodium hyaluronate because the certainty of evidence is very low (RR 2.50, 95% CI 0.71 to 8.83; 1 trial, 14 ulcers from 10 participants). Foot ulcers in people with diabetes It is uncertain whether there is a difference in time to complete healing between hyaluronic acid and lyophilised collagen because the certainty of evidence is very low (MD 16.60, 95% CI 7.95 to 25.25; 1 study, 20 participants). It is uncertain whether there is a difference in complete ulcer healing (RR 2.20, 95% CI 0.97 to 4.97; 1 study, 34 participants) or change in ulcer size (MD -0.80, 95% CI -3.58 to 1.98; 1 study, 25 participants) between hyaluronic acid and conventional dressings because the certainty of evidence is very low. Leg ulcers We are uncertain whether there is a difference in complete wound healing (RR 0.98, 95% CI 0.26 to 3.76), percentage of adverse events (RR 0.79, 95% CI 0.22 to 2.80), pain (MD 2.10, 95% CI -5.81 to 10.01), or change in ulcer size (RR 2.11, 95% CI 0.92 to 4.82) between hyaluronic acid + hydrocolloid and hydrocolloid because the certainty of evidence is very low (1 study, 125 participants). It is uncertain whether there is a difference in change in ulcer size between hyaluronic acid and hydrocolloid because the certainty of evidence is very low (RR 1.02, 95% CI 0.84 to 1.25; 1 study, 143 participants). We are uncertain whether there is a difference in complete wound healing between hyaluronic acid and paraffin gauze because the certainty of evidence is very low (RR 2.00, 95% CI 0.21 to 19.23; 1 study, 24 ulcers from 17 participants). When compared with neutral vehicle, hyaluronic acid probably improves complete ulcer healing (RR 2.11, 95% CI 1.46 to 3.07; 4 studies, 526 participants; moderate-certainty evidence); may slightly increase the reduction in pain from baseline (MD -8.55, 95% CI -14.77 to -2.34; 3 studies, 337 participants); and may slightly increase change in ulcer size, measured as mean reduction from baseline to 45 days (MD 30.44%, 95% CI 15.57 to 45.31; 2 studies, 190 participants). It is uncertain if hyaluronic acid alters incidence of infection when compared with neutral vehicle (RR 0.89, 95% CI 0.53 to 1.49; 3 studies, 425 participants). We are uncertain whether there is a difference in change in ulcer size (cm2) between hyaluronic acid and dextranomer because the certainty of evidence is very low (MD 5.80, 95% CI -10.0 to 21.60; 1 study, 50 participants). We downgraded the certainty of evidence due to risk of bias or imprecision, or both, for all of the above comparisons. No trial reported health-related quality of life or wound recurrence. Measurement of change in ulcer size was not homogeneous among studies, and missing data precluded further analysis for some comparisons.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine the effectiveness of hyaluronic acid dressings in the healing of pressure ulcers or foot ulcers in people with diabetes. We found evidence that hyaluronic acid probably improves complete ulcer healing and may slightly decrease pain and increase change in ulcer size when compared with neutral vehicle. Future research into the effects of hyaluronic acid in the healing of chronic wounds should consider higher sample size and blinding to minimise bias and improve the quality of evidence.

A versatile, bioengineered skin reconstruction device designed for use in austere environments

Austere environments in which access to medical facilities, medical personnel, or even water and electricity is limited or unavailable pose unique challenges for medical device product design. Currently existing skin substitutes are severely inadequate for the treatment of severe burns, chronic wounds, battlefield injuries, or work-related injuries in resource-limited settings. For such settings, an ideal device should be biocompatible, bioresorbable, promote tissue healing, not require trained medical personnel for deployment and use, and should enable topical drug delivery. As proof of concept for such a device, silk fibroin and an antioxidant hyaluronic acid derivative were chosen as primary constituents. The final formulation was selected to optimize tensile strength while retaining mechanical compliance and protection from reactive oxygen species (ROS). The ultimate tensile strength of the device was 438.0 KPa. Viability of dermal fibroblasts challenged with ROS-generating menadione decreased to 49.7% of control, which was rescued by pre-treatment with the hyaluronic acid derivative to 85.0% of control. The final device formulation was also tested in a standardized, validated, in vitro skin irritation test which revealed no tissue damage or statistical difference from control. Improved topical drug delivery was achieved via an integrated silk fibroin microneedle array and selective device processing to generate crosslinked/through pores. The final device including these features showed a 223% increase in small molecule epidermal permeation relative to the control. Scaffold porosity and microneedle integrity before and after application were confirmed by electron microscopy. Next, the device was designed to be self-adherent to enable deployment without the need of traditional fixation methods. Device tissue adhesive strength (12.0 MPa) was evaluated and shown to be comparable to a commercial adhesive surgical drape (12.9 MPa) and superior to an over-the-counter liquid bandage (4.1 MPa). Finally, the device's wound healing potential was assessed in an in vitro full-thickness skin wound model which showed promising device integration into the tissue and cellular migration into and above the device. Overall, these results suggest that this prototype, specifically designed for use in austere environments, is mechanically robust, is cytocompatible, protects from ROS damage, is self-adherent without traditional fixation methods, and promotes tissue repair.

Biomaterials and tissue engineering approaches using glycosaminoglycans for tissue repair: Lessons learned from the native extracellular matrix

Glycosaminoglycans (GAGs) are an important component of the extracellular matrix as they influence cell behavior and have been sought for tissue regeneration, biomaterials, and drug delivery applications. GAGs are known to interact with growth factors and other bioactive molecules and impact tissue mechanics. This review provides an overview of native GAGs, their structure, and properties, specifically their interaction with proteins, their effect on cell behavior, and their mechanical role in the ECM. GAGs' function in the extracellular environment is still being understood however, promising studies have led to the development of medical devices and therapies. Native GAGs, including hyaluronic acid, chondroitin sulfate, and heparin, have been widely explored in tissue engineering and biomaterial approaches for tissue repair or replacement. This review focuses on orthopaedic and wound healing applications. The use of GAGs in these applications have had significant advances leading to clinical use. Promising studies using GAG mimetics and future directions are also discussed. STATEMENT OF SIGNIFICANCE: Glycosaminoglycans (GAGs) are an important component of the native extracellular matrix and have shown promise in medical devices and therapies. This review emphasizes the structure and properties of native GAGs, their role in the ECM providing biochemical and mechanical cues that influence cell behavior, and their use in tissue regeneration and biomaterial approaches for orthopaedic and wound healing applications.

Effects of Therapeutic Platelet-Rich Plasma on Overactive Bladder via Modulating Hyaluronan Synthesis in Ovariectomized Rat

Postmenopausal women who have ovary hormone deficiency (OHD) may experience urological dysfunctions, such as overactive bladder (OAB) symptoms. This study used a female Sprague Dawley rat model that underwent bilateral ovariectomy (OVX) to simulate post-menopause in humans. The rats were treated with platelet-rich plasma (PRP) or platelet-poor plasma (PPP) after 12 months of OVX to investigate the therapeutic effects of PRP on OHD-induced OAB. The OVX-treated rats exhibited a decrease in the expression of urothelial barrier-associated proteins, altered hyaluronic acid (hyaluronan; HA) production, and exacerbated bladder pathological damage and interstitial fibrosis through NFƘB/COX-2 signaling pathways, which may contribute to OAB. In contrast, PRP instillation for four weeks regulated the inflammatory fibrotic biosynthesis, promoted cell proliferation and matrix synthesis of stroma, enhanced mucosal regeneration, and improved urothelial mucosa to alleviate OHD-induced bladder hyperactivity. PRP could release growth factors to promote angiogenic potential for bladder repair through laminin/integrin-α6 and VEGF/VEGF receptor signaling pathways in the pathogenesis of OHD-induced OAB. Furthermore, PRP enhanced the expression of HA receptors and hyaluronan synthases (HAS), reduced hyaluronidases (HYALs), modulated the fibroblast-myofibroblast transition, and increased angiogenesis and matrix synthesis via the PI3K/AKT/m-TOR pathway, resulting in bladder remodeling and regeneration.

Low molecular weight hyaluronates: biological action, efficacy, safety and clinical experience in the treatment of musculoskeletal pain syndromes (literature review and clinical observations)

Hyaluronic acid (HA) drugs are ingrained in complex treatment of osteoarthritis (OA). They have not only lubricant, but also anti-inflammatory properties, and ability to slow down the progression of OA. The article summarizes current data on the efficacy and safety of low molecular weight HA. The possibilities of using it both intra-articularly (i/a) and for the treatment of tendinopathies are considered. The authors present their own clinical experience in the treatment of patients with musculoskeletal (MS) pain syndromes.It has been shown that i/a administration of HA can effectively reduce the intensity of pain and improve joint function, and when injected into the synovial sheaths of tendons, it can also relieve pain of extra-articular localization. The peculiarities of the surgical technique, preparing for manipulation and post-injection period management are described.The existing evidence base indicates the expediency of active use of HA drugs not only for OA treatment, but also for various extra-articular musculoskeletal pain syndromes.

Unilateral hard palate necrosis following gingival injections with hyaluronic acid

Hyaluronic acid (HA) injections into the oral mucosa have proven to be effective as a non-invasive method for the reconstruction of interproximal papillary defects in aesthetic areas. Despite being a minimally invasive and safe technique, certain side effects may occur after treatment.We report the first case of a patient with unilateral necrosis of the mucosa of the hard palate after HA filling in the maxillary anterior gingiva. Familiarity with these events and competent knowledge of the anatomy is essential to avoid complications, achieve and offer adequate treatment and good results to our patients.

Piperine-loaded nanoparticles incorporated into hyaluronic acid/sodium alginate-based membranes for the treatment of inflammatory skin diseases

Piperine is an alkaloid mostly found in the fruits of several species of the Piper genus, and its anti-inflammatory potential is already known. However, its therapeutic applications still need to be better explored due to the low aqueous solubility of this active. To overcome this drawback, the objective of this work was to evaluate the efficiency of the nanoencapsulation of the compound as well as its incorporation into hyaluronic acid/alginate-based biomembranes. Polymeric nanoparticles composed of Eudragit S100 and Poloxamer 188 were obtained by the nanoprecipitation technique, obtaining spherical nanosized particles with an average diameter of 122.1 ± 2.0 nm, polydispersity index of 0.266, and encapsulation efficiency of 76.2 %. Hyaluronic acid/sodium alginate membranes were then prepared and characterized. Regarding permeation, a slow passage rate was observed until the initial 14 h, when an exponential increase in the recovered drug concentration began to occur. The in vivo assay showed a reduction in inflammation up to 43.6 %, and no cytotoxicity was observed. The results suggested the potential of the system developed for the treatment of inflammatory skin diseases.

Three-Dimensional Digital Light-Processing Bioprinting Using Silk Fibroin-Based Bio-Ink: Recent Advancements in Biomedical Applications

Three-dimensional (3D) bioprinting has been developed as a viable method for fabricating functional tissues and organs by precisely spatially arranging biomaterials, cells, and biochemical components in a layer-by-layer fashion. Among the various bioprinting strategies, digital light-processing (DLP) printing has gained enormous attention due to its applications in tissue engineering and biomedical fields. It allows for high spatial resolution and the rapid printing of complex structures. Although bio-ink is a critical aspect of 3D bioprinting, only a few bio-inks have been used for DLP bioprinting in contrast to the number of bio-inks employed for other bioprinters. Recently, silk fibroin (SF), as a natural bio-ink material used for DLP 3D bioprinting, has gained extensive attention with respect to biomedical applications due to its biocompatibility and mechanical properties. This review introduces DLP-based 3D bioprinting, its related technology, and the fabrication process of silk fibroin-based bio-ink. Then, we summarize the applications of DLP 3D bioprinting based on SF-based bio-ink in the tissue engineering and biomedical fields. We also discuss the current limitations and future perspectives of DLP 3D bioprinting using SF-based bio-ink.

Bioactive Saponins of Primula vulgaris Huds. Promote Wound Healing through Inhibition of Collagenase and Elastase Enzymes: in Vivo, in Vitro and in Silico Evaluations

Primula vulgaris Huds. leaves and roots were used to treat skin damage and inflammation in Anatolian Folk Medicine. This study aimed to assess the ethnopharmacological use of the plant using in vivo, in vitro, and in silico test models. Linear incision and circular excision wound models were used to determine the in vivo wound-healing potential of the plant extracts and fractions. In vitro assays including hyaluronidase, collagenase, and elastase inhibitory activities were carried out for the active compounds to discover their activity pathways. Structure-based molecular modeling was performed to understand inhibitory mechanisms regarding collagenase and elastase at the molecular level. The butanol fraction of the roots of P. vulgaris showed the highest wound-healing activity. Through activity-guided fractionation and isolation techniques, primulasaponin I (1) and primulasaponin I methyl ester (2) were stated as the major active compounds. These compounds exerted their activities through the inhibition of collagenase and elastase enzymes. Primulasaponin I methyl ester isolated from butanol fraction was found to be the strongest agent, especially with the values of 29.65 % on collagenase and 38.92 % on elastase inhibitory activity assays, as well as molecular docking studies. The present study supports scientific data for the traditional use of P. vulgaris and the wound healing properties of the plant can be referred to secondary metabolites as especially saponins found in the roots.

Use of radiolabeled hyaluronic acid for preclinical assessment of inflammatory injury and acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is accompanied by a dramatic increase in lung hyaluronic acid (HA), leading to a dose-dependent reduction of pulmonary oxygenation. This pattern is associated with severe infections, such as COVID-19, and other important lung injury etiologies. HA actively participates in molecular pathways involved in the cytokine storm of COVID-19-induced ARDS. The objective of this study was to evaluate an imaging approach of radiolabeled HA for assessment of dysregulated HA deposition in mouse models with skin inflammation and lipopolysaccharide (LPS)-induced ARDS using a novel portable intensified Quantum Imaging Detector (iQID) gamma camera system.

METHODS

HA of 10 kDa molecular weight (HA10) was radiolabeled with 125I and 99mTc respectively to produce [125I]I-HA10 and [99mTc]Tc-HA10, followed by comparative studies on stability, in vivo biodistribution, and uptake at inflammatory skin sites in mice with 12-O-tetradecanoylphorbol-13-acetate (TPA)-inflamed ears. [99mTc]Tc-HA10 was used for iQID in vivo dynamic imaging of mice with ARDS induced by intratracheal instillation of LPS.

RESULTS

[99mTc]Tc-HA10 and [125I]I-HA10 had similar biodistribution and localization at inflammatory sites. [99mTc]Tc-HA10 was shown to be feasible in measuring skin injury and monitoring skin wound healing. [99mTc]Tc-HA10 dynamic pulmonary images yielded good visualization of radioactive uptake in the lungs. There was significantly increased lung uptake and slower lung washout in mice with LPS-induced ARDS than in control mice. Postmortem biodistribution measurement of [99mTc]TcHA10 (%ID/g) was 11.0 ± 3.9 vs. 1.3 ± 0.3 in the ARDS mice (n = 6) and controls (n = 6) (P < 0.001), consistent with upregulated HA expression as determined by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) staining.

CONCLUSIONS

[99mTc]Tc-HA10 is promising as a biomarker for evaluating HA dysregulation that contributes to pulmonary injury in ARDS. Rapid iQID imaging of [99mTc]Tc-HA10 clearance from injured lungs may provide a functional template for timely assessment and quantitative monitoring of pulmonary pathophysiology and intervention in ARDS.

Correlation of cell mechanics with the resistance to malignant transformation in naked mole rat fibroblasts

Naked mole rats (NMRs) demonstrate exceptional longevity and resistance to cancer. Using a biochemical approach, it was previously shown that the treatment of mouse fibroblast cells with RasV12 oncogene and SV40 Large T antigen (viral oncoprotein) led to malignant transformations of cells. In contrast, NMR fibroblasts were resistant to malignant transformations upon this treatment. Here we demonstrate that atomic force microscopy (AFM) can provide information which is in agreement with the above finding, and further, adds unique information about the physical properties of cells that is impossible to obtain by other existing techniques. AFM indentation data were collected from individual cells and subsequently processed through the brush model to obtain information about the mechanics of the cell body (absolute values of the effective Young's moduli). Furthermore, information about the physical properties of the pericellular layer surrounding the cells was obtained. We found a statistically significant decrease in the rigidity of mouse cells after the treatment, whereas there was no significant change found in the rigidity of NMR cells upon the treatment. We also found that the treatment caused a substantial increase in a long part of the pericellular layer in NMR cells only (the long brush was defined as having a size of >10 microns). The mouse cells and smaller brush did not show statistically significant changes upon treatment. The observed change in cell mechanics is in agreement with the frequently observed decrease in cell rigidity during progression towards cancer. The change in the pericellular layer due to the malignant transformation of fibroblast cells has practically not been studied, though it was shown that the removal of part of the pericellular layer of NMR fibroblasts made the cells susceptible to malignant transformation. Although it is plausible to speculate that the observed increase in the long part of the brush layer of NMR cells might help cells to resist malignant transformations, the significance of the observed change in the pericellular layer is yet to be understood. As of now, we can conclude that changes in cell mechanics might be used as an indication of the resistance of NMR cells to malignant transformations.

Hyaluronic Acid as an Adjunct to Coronally Advanced Flap Procedures for Gingival Recessions: A Systematic Review and Meta—Analysis of Randomized Clinical Trials

Previous systematic reviews have reported that coronally advanced flap (CAF) + connective tissue graft (CTG) are the gold standard in root coverage procedures (RCP). Nevertheless, adjunctive treatment with hyaluronic acid (HA) has been proposed to aim at improving clinical outcomes and reducing patient morbidity. The aim of this systematic review and meta-analysis is to compare the use of HA as an adjunctive treatment to CAF procedures in Miller class I and II (recession type 1; RT1) gingival recession (GR) defects treatment with no adjunctive/other treatments. MEDLINE, The Cochrane Central Register of Controlled Trials, Web of Science, Scopus databases and gray literature were searched up to April 2022. The primary outcome variables were mean recession coverage (MRC) and reduction of the recession depth (RecRed). Weighted mean differences and 95% confidence intervals between treatments were estimated using a random-effect mode. From 264 titles identified, 3 RCTs reporting 90 GR defects in 60 patients were included. Overall analysis of MRC and RecRed were 0.27% (p = 0.01) and 0.40 mm (p = 0.45) in favor of CAF + HA compared to CAF alone/CAF + subepithelial connective tissue graft (SCTG), respectively, with a statistically significant difference only for MRC values. Nevertheless, due to the limited number and heterogeneity of the included studies, well-performed RCTs are needed to clarify a potential advantage of HA in RCPs in the future.

Minor Recurrent Aphthous Ulcer Management with Hyaluronic Acid Gel in an Italian Cohort: A Double-Blind Randomized Clinical Trial

Background. Recurrent aphthous ulcer is a common mucosal disease and encompasses diverse interventions for its management of symptoms like pain and discomfort. Since new therapies keep evolving with better outcomes as compared to traditional interventions, one such therapy using hyaluronic acid has been recently explored using clinical studies based on advances in dental therapeutics. Therefore, we designed this clinical study which is double blinded and randomized using minor recurrent aphthous cases. Objective. To evaluate the efficacy of hyaluronic acid topical oral gel in the treatment of minor RAS ulcers, with regard to pain relief and reduction in ulcer size. Design. A double-blind randomized controlled clinical trial was designed to conduct an experimental research at IRCCS Fondazione Ca’ Granda, Ospedale Maggiore Policlinico, Milan. The participants were recruited from the unit of oral maxillofacial surgery and randomly assigned to test (hyaluronic acid gel) and control groups (placebo gel). 1 : 1 computer-generated random sequence was prepared, and opaque closed envelopes were used for allocation concealment. Participants and clinical investigators were blinded. The outcome measures included ulcer size (mm) and the visual analogue scale for pain and healing as a secondary outcome measure (efficacy index). Results. The mean baseline score for ulcer size for the test group was $1.85\pm 1$ and the placebo group was $1.85\pm 1.2$ . At day 7, the test group was $1\pm 1.5$ and the placebo group was $2\pm 1.5$ ( $p<0.001$ ). There was significant reduction in ulcer size as compared to the placebo group. In addition, there was significant improvement in pain levels ( $p<0.01$ ) in the test group as compared to the control group. Conclusion. In conclusion, there was significant decrease in the size of the ulcer in the test group as compared to the placebo group. Hyaluronic acid seems to have promising effects on the ulcer size and pain relief associated with minor aphthous ulcers. Trial Registration. The protocol of this clinical trial was registered with the Clinical Trial Registry of ISRCTN with study ID ISRCTN16509838, registered 30 June 2020. It can be accessed on this URL: 10.1186/ISRCTN16509838

Structural design and mechanical performance of composite vascular grafts

This study reviews the state of the art in structural design and the corresponding mechanical behaviours of composite vascular grafts. We critically analyse surface and matrix designs composed of layered, embedded, and hybrid structures along the radial and longitudinal directions; materials and manufacturing techniques, such as tissue engineering and the use of textiles or their combinations; and the corresponding mechanical behaviours of composite vascular grafts in terms of their physical–mechanical properties, especially their stress–strain relationships and elastic recovery. The role of computational studies is discussed with respect to optimizing the geometrics designs and the corresponding mechanical behaviours to satisfy specialized applications, such as those for the aorta and its subparts. Natural and synthetic endothelial materials yield improvements in the mechanical and biological compliance of composite graft surfaces with host arteries. Moreover, the diameter, wall thickness, stiffness, compliance, tensile strength, elasticity, and burst strength of the graft matrix are determined depending on the application and the patient. For composite vascular grafts, hybrid architectures are recommended featuring multiple layers, dimensions, and materials to achieve the desired optimal flexibility and function for complying with user-specific requirements. Rapidly emerging artificial intelligence and big data techniques for diagnostics and the three-dimensional (3D) manufacturing of vascular grafts will likely yield highly compliant, subject-specific, long-lasting, and economical vascular grafts in the near-future.

Graphic abstract

Exosomes of mesenchymal stem cells delivered from methacrylated hyaluronic acid patch improve the regenerative properties of endothelial and dermal cells

Wound care management urgently needs the development of innovative smart wound dressings. The complexity of the wound often requires the use of personalized medication and the advent of three-dimensional (3D) bioprinting fits strongly with this need. In this view, in the present work a methacrylated hyaluronic acid (MeHA) bioink was tested for the fabrication of advanced smart patches as a delivery system of exosomes derived from human mesenchymal stem cells (hMSC-EXOs) suitable for wound healing purposes. MeHA patches were realized by 3D bioprinting technique and they were loaded with hMSC-EXOs. The 3D printed MeHA patches revealed improved mechanical performance, appropriate swelling ratio, extended degradation time, and suitable biocompatibility. Furthermore, MeHA patches loaded with hMSC-EXOs improved the proliferation, migration, angiogenic ability, and expression of specific markers related to wound healing process in human fibroblasts and human endothelial cells.

Modified hyaluronic acid-collagen matrices trigger efficient gene transfer and prohealing behavior in fibroblasts for improved wound repair

Growth factor therapy has demonstrated great promise for chronic wound repair, but controlling growth factor activity and cell phenotype over desired time frames remains a critical challenge. In this study, we developed a gene-activated hyaluronic acid-collagen matrix (GAHCM) comprising DNA/polyethylenimine (PEI) polyplexes retained on hyaluronic acid (HA)-collagen hydrogels using collagen mimetic peptides (CMPs). We hypothesized that manipulating both the number of CMP-collagen tethers and the ECM composition would provide a powerful strategy to control growth factor gene transfer kinetics while regulating cell behavior, resulting in enhanced growth factor activity for wound repair. We observed that polyplexes with 50% CMP-modified PEI (50 CP) showed enhanced retention of polyplexes in HCM hydrogels by 2.7-fold as compared to non-CMP modified polyplexes. Moreover, the incorporation of HA in the hydrogel promoted a significant increase in gene transfection efficiency based upon analysis of Gaussia luciferase (GLuc) reporter gene expression, and gene expression could be attenuated by blocking HA-CD44 signaling. Furthermore, when fibroblasts were exposed to vascular endothelial growth factor-A (VEGF-A)-GAHCM, the 50 CP matrix facilitated sustained VEGF-A production for up to 7 days, with maximal expression at day 5. Application of these VEGF-A-50 CP samples stimulated prolonged pro-healing responses, including the TGF-β1-induced myofibroblast-like phenotypes and enhanced closure of murine splinted wounds. Overall, these findings demonstrate the use of ECM-based materials to stimulate efficient gene transfer and regulate cellular phenotype, resulting in improved control of growth factor activity for wound repair. GAHCM have significant potential to overcome key challenges in growth factor therapy for regenerative medicine. STATEMENT OF SIGNIFICANCE: Despite great promise for growth factor therapies in wound treatment, controlling growth factor activity and providing a microenvironment for cells that maximizes growth factor signaling have continued to limit the success of existing formulations. Our GAHCM strategy, combining CMP gene delivery and hyaluronic acid-collagen matrix, enabled enhanced wound healing efficacy via the combination of controlled and localized growth factor expression and matrix-mediated regulation of cell behavior. Incorporation of CMPs and HA in the same matrix synergistically enhanced VEGF activity as compared with simpler matrices. Accordingly, GAHCM will advance our ability to leverage growth factor signaling for wound healing, resulting in new long-term treatments for recalcitrant wounds.

Contribution of Topical Agents such as Hyaluronic Acid and Silver Sulfadiazine to Wound Healing and Management of Bacterial Biofilm

Background and Objectives: Wound healing is commonly associated with critical bacterial colonization or bacterial infection, which induces prolonged inflammation, resulting in delayed re-epithelialization. An appropriate wound dressing requires a humid environment, which also functions as a barrier against bacterial contamination and will accelerate a regenerative response of the wound. Silver sulfadiazine (SSD) is used to prevent wound infection. Hyaluronic acid (HA) is an extracellular matrix component involved in tissue regeneration. This retrospective study was conducted to evaluate the effectiveness of cream and gauze pads based on hyaluronic acid at low molecular weight (200 kDa) and silver sulfadiazine 1% in the wound healing process. In addition, we examined SSD action on biofilms in vitro and on animal wounds, obtaining positive outcomes therefrom. Materials and Methods: We selected 80 patients with complicated chronic wounds of different etiologies, including diabetes mellitus (10), post-traumatic ulcers (45), burns (15), and superficial abrasion (10). Results: After 8 weeks, ulcer size was decreased in 95 ± 2% of the treated patients; a significant reduction in the inflammatory process was observed from day 14 onwards (p < 0.01 vs. baseline), considering improvement of the surrounding skin and reduction of the bacterial load. The SSD treatment decreased bacterial colony proliferation, both in planktonic state and in biofilm, in a dose-dependent manner on the wound but inhibited the development of tissue granulation at the highest dose (800 μg/wound). Conclusions: In conclusion, the combined action of SSD and HA is clinically effective in improving wound healing.

Hyaluronic Acid with Bone Substitutes Enhance Angiogenesis In Vivo

Introduction: The effective induction of angiogenesis is directly related to the success of bone-substitute materials (BSM) for maxillofacial osseous regeneration. Therefore, the addition of pro-angiogenic properties to a commercially available bovine bone-substitute material in combination with hyaluronic acid (BSM+) was compared to the same bone-substitute material without hyaluronic acid (BSM) in an in-vivo model. Materials and Methods: BSM+ and BSM were incubated for six days on the chorioallantoic membrane (CAM) of fertilized chicken eggs. Microscopically, the number of vessels and branching points, the vessel area and vessel length were evaluated. Subsequently, the total vessel area and brightness integration were assessed after immunohistochemical staining (H&E, alphaSMA). Results: In the BSM+ group, a significantly higher number of vessels (p < 0.001), branching points (p = 0.001), total vessel area (p < 0.001) as well as vessel length (p = 0.001) were found in comparison to the BSM group without hyaluronic acid. Immunohistochemically, a significantly increased total vessel area (p < 0.001 for H&E, p = 0.037 for alphaSMA) and brightness integration (p = 0.047) for BSM+ in comparison to the native material were seen. Conclusions: The combination of a xenogenic bone-substitute material with hyaluronic acid significantly induced angiogenesis in vivo. This might lead to a faster integration and an improved healing in clinical situations.

Efficiency of a biodegradable gel containing hyaluronic acid and berberine hydrochloride in endoscopic sinus surgery (ESS): A prospective comparative study

PURPOSE

To evaluate the efficiency of a biodegradable gel containing hyaluronic acid and berberine hydrochloride in endoscopic sinus surgery.

METHODS

Sixty-six chronic rhinosinusitis patients with or without nasal polyps who underwent bilateral endoscopic sinus surgery (ESS) were randomly received a biodegradable gel containing hyaluronic acid and berberine hydrochloride or merocel in both middle meatal spacers at the end procedure of ESS. Lund-Kennedy endoscopic score (LKES) was used to examine status of nasal cavity on preoperative day and postoperative day 1 to 7. The LKES ratio was calculated as the LKES on postoperative day divided into the LKES on preoperative day. Visual analogue score (VAS) was used to assess patient's status from the first postoperative day to the hospital discharge day. The average VAS during hospital stays was calculated by the sum of VAS in each examination day divided into the number of examined day. The LKES ratio, the average of VAS during hospital stays and length of hospitalized day of the patients were used as clinical outcome indices in early stage after surgery. A general linear model adjusted for confounding factors was used for data analysis.

RESULTS

Adjusted mean of LKES ratio were lower in group used biodegrable gel of hyaruloic acid and berberin hydrochlode (study group) than those in merocele group in the postoperative day 1 to day 7. However, significant difference was found in the adjusted mean of LKES ratio on the postoperative day 2 to 6. Similarly, the adjusted mean of VAS during hospital stays and length of hospitalized day after surgery in study group were significantly decreased as compared with those in merocele group.

CONCLUSIONS

Biodegradable material containing hyaluronic acid and berberine hydrochloride was more effective than merocel in length of hospital stay, post-operative symptoms, and sinus cavity's status in early stage after ESS.

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

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