Efficacy and safety of hyaluronic acid in the management of acute wounds

The design principle of natural polysaccharide hydrogels for promoting wound healing: a prospective review

Acute skin injuries and chronic non-healing wounds are common in daily life, posing significant physical trauma to patients and creating substantial social and economic burdens. Polysaccharide-based hydrogels not only maintain optimal moisture levels for wound recovery but also act as effective barriers against bacterial infection. Polysaccharides, with their unique properties such as biocompatibility, biodegradability, and non-toxicity, are promising materials for constructing hydrogels designed for wound healing. This review discusses wound physiology, key design factors for wound-healing hydrogels, and the fundamental principles of hydrogel gelation. It also provides an overview of the current applications of polysaccharide-based hydrogels-including those derived from hyaluronic acid, chitosan, sodium alginate, cellulose, glucose, and starch-as advanced wound dressings. Finally, the review outlines current challenges and future research directions for polysaccharide-based hydrogels in wound healing, aiming to inspire further exploration and innovation in this field.

Electrospun scaffold with bioactive polyurethane shell infused with propolis and starch-hyaluronic acid core: An advanced therapeutic platform for skin tissue engineering

Biological macromolecules such as polysaccharides and proteins, due to their excellent biocompatibility and biodegradability, are ideal for promoting Skin Tissue Engineering (STE) both in vitro and in vivo. In this study, a core-shell electrospun scaffold was fabricated using the coaxial electrospinning method, with Polyurethane (PU) forming the shell and a mixture of Starch (ST), Propolis Extract (PE), and Hyaluronic Acid (HA) forming the core. The scaffold's morphology was characterized by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), confirming the successful formation of a well-defined core-shell structure. The scaffold exhibited a contact angle of 56.7°, reflecting its favorable hydrophilic properties for cellular attachment. Mechanical testing revealed Young's modulus of 8.12 MPa and a strain at break of 46 %, indicating an optimal balance of mechanical strength and elasticity for STE. Antibacterial tests demonstrated that the core-shell structure exhibited strong antimicrobial activity against Staphylococcus aureus and Escherichia coli, making them a potential candidate. Cytotoxicity assessments showed no toxicity, with L929 fibroblast cells demonstrating enhanced adhesion and proliferation on the core-shell structure compared to control samples. These findings suggest that the PU-shell and ST/PE/HA-core electrospun scaffold represents a promising multifunctional platform for advanced STE and regenerative medicine applications.

Sticky Science: Using Complex Coacervate Adhesives for Biomedical Applications

Tissue adhesives are used for various medical applications, including wound closure, bleeding control, and bone healing. Currently available options often show weak adhesion or cause adverse effects. Recently, there has been an increasing interest in complex coacervates as medical adhesives. Complex coacervates are formed by mixing oppositely charged macromolecules that associate and undergo liquid-liquid phase separation, in which the dense bottom phase is the complex coacervate. Complex coacervates are strong and often biocompatible, and show strong underwater adhesion. The properties of the resulting materials are tunable by intrinsic factors such as polymer chemistry, molecular weight, charge density, and topology of the macromolecules, as well as extrinsic factors such as temperature, pH, and salt concentration. Therefore, complex coacervates are interesting new candidates for medical adhesives. In this review, it is described how complex coacervates form and how different factors influence their behavior. Next, an overview of recent studies on complex coacervates in the context of medical adhesives is presented. The application of complex coacervates as hemostatic or embolic agents, skin or bone repair adhesives, and soft tissue sealants is discussed. Lastly, additional possibilities for utilizing these materials in the future are discussed.

Effect of hyaluronic acid on palatal wound healing: A systematic review

OBJECTIVES

To evaluate the efficacy of topically applied hyaluronic acid on wound healing (patient-reported outcomes and clinical healing) after a palatal autogenous gingival graft is harvested.

MATERIALS AND METHODS

A systematic search was performed in April 2024 in eleven electronic databases. Two investigators independently screened the references for inclusion. Outcomes of interest included postoperative pain, analgesic consumption, complete epithelialization, and color match, which were synthesized using narrative synthesis.

RESULTS

A total of 535 results were identified and eight articles were included in the systematic review. Hyaluronic acid use on the palatal donor site had a better response to healing and wound size compared to the control sites with no agent applied. Hyaluronic acid demonstrated a positive effect in the form of complete epithelialization, and color match, with improved patient-reported outcomes such as post-operative pain.

CONCLUSION

Within the limitations of this systematic review, it can be concluded that hyaluronic acid shows a strong potential to improve patient-reported outcomes and clinical wound healing at the graft donor site on the palate. Future studies are required to clarify the optimal concentration, frequency of application, and synergistic effect when HA is combined with other interventions.

CLINICAL RELEVANCE

Within the limitations of this systematic review, it can be concluded that hyaluronic acid shows a strong potential to improve patient-reported outcomes and clinical wound healing at the graft donor site on the palate. Future studies are required to clarify the optimal concentration, frequency of application, and synergistic effect when HA is combined with other interventions.

The Effect of Polynucleotide-Hyaluronic Acid Hydrogel in the Recovery After Mechanical Skin Barrier Disruption

BACKGROUND

The epidermal barrier acts as a defense against external agents as well as helps to maintain body homeostasis. Polynucleotides (PN), exogenous DNA fragments, promote wound repair through their stimulatory and anti-inflammatory effects. Recent findings indicate a synergistic effect of PN and hyaluronic acid (HA) combinations in regulating inflammation and promoting cell proliferation. This study aims to elucidate the effects of PN and HA on repairing the epidermal barrier following its disruption by tape stripping (TS) in a mouse model.

MATERIALS AND METHODS

After disrupting the epidermal barrier using TS, a formulation containing PN (14 mg/mL) and HA (6 mg/mL) was applied. Trans-epidermal water loss (TEWL) was measured at 0, 3, 6, 24, 48, and 72 h. Mice were euthanized after the final application at 72 h, and tissue samples were analyzed for epidermal/dermal thickness, neutrophil infiltration, and filaggrin expression.

RESULTS

We observed a significant reduction in TEWL in the PN+HA group compared to that in the control group (20.8 ± 0.5 vs. 43.7 ± 0.5 g/m2h at 72 h, p < 0.05), indicating an improvement in barrier function. Histological evaluation showed decreased epidermal and dermal thickening in the PN+HA group compared to that in the control group (epidermal: 29.4 ± 2.2 vs. 57.9 ± 3.5 μm; dermal: 464.8 ± 25.9 vs. 825.9 ± 44.8 μm, both p < 0.05). Additionally, neutrophil infiltration in the dermis was significantly reduced, and filaggrin protein levels were significantly higher in the PN+HA group compared to those in the control group (4.8 ± 0.4 vs. 21.1 ± 3.3 for neutrophils; 0.84 ± 0.04 vs. 0.42 ± 0.03 for filaggrin, both p < 0.05).

CONCLUSION

These results suggest that PN+HA may be an effective therapeutic strategy for repairing skin barrier damage.

Development and characterization of an emulgel based on a snail slime useful for dermatological applications

Snail slime is an interesting material for effective dermatological use (e.g. wounds). Its properties are stricly connected to the origin. In this paper a snail slime, deriving from the species Helix aspersa Muller and obtained from a company, was deeply characterized and then properly formulated. The slime, obtained by Donatella Veroni method, was firstly submitted to NMR analysis in order to evaluate the chemical composition. The main molecules found are glycolate and allantoin, well known for their activities in wound healing promotion. In vitro experiments performed on keratinocytes, revealed the snail slime ability to promote cellular well-being. Moreover, the microbiological analysis showed high activity against many strains involved in wounds infections such as gram+ (e.g. S. aureus, S. pyogenes), gram- (e.g. P. aeruginosa, E. coli) and the yeast C. albicans. The effect on skin elasticity was evaluated as well by the instrument Cutometer® dualMPA580. The snail slime was then formulated as hydrophilic gel, using a combination of corn starch and sodium hyaluronate as polymers, then used as external water phase of an O/W emulgel. The formulation is physically stable and easily spreadable and demonstrated antimicrobial activity as observed for slime alone, suggesting its suitability to be used for wound treatment.

Interventions for postburn pruritus

BACKGROUND

Postburn pruritus (itch) is a common and distressing symptom experienced on healing or healed burn or donor site wounds. Topical, systemic, and physical treatments are available to control postburn pruritus; however, it remains unclear how effective these are.

OBJECTIVES

To assess the effects of interventions for treating postburn pruritus in any care setting.

SEARCH METHODS

In September 2022, we searched the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE (including In-Process & Other Non-Indexed Citations), Ovid Embase, and EBSCO CINAHL Plus. We also searched clinical trials registries and scanned references of relevant publications to identify eligible trials. There were no restrictions with respect to language, publication date, or study setting.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that enrolled people with postburn pruritus to compare an intervention for postburn pruritus with any other intervention, placebo or sham intervention, or no intervention.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included 25 RCTs assessing 21 interventions with 1166 randomised participants. These 21 interventions can be grouped into six categories: neuromodulatory agents (such as doxepin, gabapentin, pregabalin, ondansetron), topical therapies (such as CQ-01 hydrogel, silicone gel, enalapril ointment, Provase moisturiser, beeswax and herbal oil cream), physical modalities (such as massage therapy, therapeutic touch, extracorporeal shock wave therapy, enhanced education about silicone gel sheeting), laser scar revision (pulsed dye laser, pulsed high-intensity laser, fractional CO2 laser), electrical stimulation (transcutaneous electrical nerve stimulation, transcranial direct current stimulation), and other therapies (cetirizine/cimetidine combination, lemon balm tea). Most RCTs were conducted at academic hospitals and were at a high risk of performance, attrition, and detection bias. While 24 out of 25 included studies reported change in burn-related pruritus, secondary outcomes such as cost-effectiveness, pain, patient perception, wound healing, and participant health-related quality of life were not reported or were reported incompletely. Neuromodulatory agents versus antihistamines or placebo There is low-certainty evidence that doxepin cream may reduce burn-related pruritus compared with oral antihistamine (mean difference (MD) -2.60 on a 0 to 10 visual analogue scale (VAS), 95% confidence interval (CI) -3.79 to -1.42; 2 studies, 49 participants). A change of 2 points represents a minimal clinically important difference (MCID). Due to very low-certainty evidence, it is uncertain whether doxepin cream impacts the incidence of somnolence as an adverse event compared to oral antihistamine (risk ratio (RR) 0.64, 95% CI 0.32 to 1.25; 1 study, 24 participants). No data were reported on pain in the included study. There is low-certainty evidence that gabapentin may reduce burn-related pruritus compared with cetirizine (MD -2.40 VAS, 95% CI -4.14 to -0.66; 1 study, 40 participants). A change of 2 points represents a MCID. There is low-certainty evidence that gabapentin reduces the incidence of somnolence compared to cetirizine (RR 0.02, 95% CI 0.00 to 0.38; 1 study, 40 participants). No data were reported on pain in the included study. There is low-certainty evidence that pregabalin may result in a reduction in burn-related pruritus intensity compared with cetirizine with pheniramine maleate (MD -0.80 VAS, 95% CI -1.24 to -0.36; 1 study, 40 participants). A change of 2 points represents a MCID. There is low-certainty evidence that pregabalin reduces the incidence of somnolence compared to cetirizine (RR 0.04, 95% CI 0.00 to 0.69; 1 study, 40 participants). No data were reported on pain in the included study. There is moderate-certainty evidence that ondansetron probably results in a reduction in burn-related pruritus intensity compared with diphenhydramine (MD -0.76 on a 0 to 10 numeric analogue scale (NAS), 95% CI -1.50 to -0.02; 1 study, 38 participants). A change of 2 points represents a MCID. No data were reported on pain and adverse events in the included study. Topical therapies versus relevant comparators There is moderate-certainty evidence that enalapril ointment probably decreases mean burn-related pruritus compared with placebo control (MD -0.70 on a 0 to 4 scoring table for itching, 95% CI -1.04 to -0.36; 1 study, 60 participants). No data were reported on pain and adverse events in the included study. Physical modalities versus relevant comparators Compared with standard care, there is low-certainty evidence that massage may reduce burn-related pruritus (standardised mean difference (SMD) -0.86, 95% CI -1.45 to -0.27; 2 studies, 166 participants) and pain (SMD -1.32, 95% CI -1.66 to -0.98). These SMDs equate to a 4.60-point reduction in pruritus and a 3.74-point reduction in pain on a 10-point VAS. A change of 2 VAS points in itch represents a MCID. No data were reported on adverse events in the included studies. There is low-certainty evidence that extracorporeal shock wave therapy (ESWT) may reduce burn-related pruritus compared with sham stimulation (SMD -1.20, 95% CI -1.65 to -0.75; 2 studies, 91 participants). This equates to a 5.93-point reduction in pruritus on a 22-point 12-item Pruritus Severity Scale. There is low-certainty evidence that ESWT may reduce pain compared with sham stimulation (MD 2.96 on a 0 to 25 pressure pain threshold (PPT), 95% CI 1.76 to 4.16; 1 study, 45 participants). No data were reported on adverse events in the included studies. Laser scar revision versus untreated or placebo controls There is moderate-certainty evidence that pulsed high-intensity laser probably results in a reduction in burn-related pruritus intensity compared with placebo laser (MD -0.51 on a 0 to 1 Itch Severity Scale (ISS), 95% CI -0.64 to -0.38; 1 study, 49 participants). There is moderate-certainty evidence that pulsed high-intensity laser probably reduces pain compared with placebo laser (MD -3.23 VAS, 95% CI -5.41 to -1.05; 1 study, 49 participants). No data were reported on adverse events in the included studies.

AUTHORS' CONCLUSIONS

There is moderate to low-certainty evidence on the effects of 21 interventions. Most studies were small and at a high risk of bias related to blinding and incomplete outcome data. Where there is moderate-certainty evidence, practitioners should consider the applicability of the evidence for their patients.

A clinical study of the local injection of a freshly manufactured 35 kDa hyaluronan fragment for treating chronic wounds

This study manufactured a 35 kDa hyaluronan fragment (HA35) by enzymatically degrading high-molecular-weight HA using hyaluronidase PH20 derived from bovine testis. The research then examined the therapeutic efficacy of locally administered, tissue-permeable HA35 in alleviating chronic wounds and their associated neuropathic pain. For 20 patients with nonhealing wounds and associated pain lasting over three months, 100 mg of HA35 was injected daily into the healthy skin surrounding the chronic wound for 10 days. Self-assessments before and after treatment indicated that HA35 significantly enhanced wound healing. This was evidenced by the formation of fresh granulation tissue on the wounds (p < 0.0001); reduced darkness, redness, dryness, and damage in the skin surrounding the wounds (p < 0.0001), and a decrease in wound size (p < 0.001). Remarkably, HA35 injections alleviated pain associated with chronic wounds within 24 hours (p < 0.0001). It can be concluded that the low-molecular-weight hyaluronan fragment HA35 potentially enhances the immune response and angiogenesis during wound healing.

Bringing innovative wound care polymer materials to the market: Challenges, developments, and new trends

The development of innovative products for treating acute and chronic wounds has become a significant topic in healthcare, resulting in numerous products and innovations over time. The growing number of patients with comorbidities and chronic diseases, which may significantly alter, delay, or inhibit normal wound healing, has introduced considerable new challenges into the wound management scenario. Researchers in academia have quickly identified promising solutions, and many advanced wound healing materials have recently been designed; however, their successful translation to the market remains highly complex and unlikely without the contribution of industry experts. This review article condenses the main aspects of wound healing applications that will serve as a practical guide for researchers working in academia and industry devoted to designing, evaluating, validating, and translating polymer wound care materials to the market. The article highlights the current challenges in wound management, describes the state-of-the-art products already on the market and trending polymer materials, describes the regulation pathways for approval, discusses current wound healing models, and offers a perspective on new technologies that could soon reach consumers. We envision that this comprehensive review will significantly contribute to highlighting the importance of networking and exchanges between academia and healthcare companies. Only through the joint of these two actors, where innovation, manufacturing, regulatory insights, and financial resources act in harmony, can wound care products be developed efficiently to reach patients quickly and affordably.

Exploring polysaccharide-based bio-adhesive topical film as a potential platform for wound dressing application: A review

Wound dressings act as a physical barrier between the wound site and the external environment, preventing additional harm; choosing suitable wound dressings is essential for the healing process. Polysaccharide biopolymers have demonstrated encouraging findings and therapeutic prospects in recent decades about wound therapy. Additionally, polysaccharides have bioactive qualities like anti-inflammatory, antibacterial, and antioxidant capabilities that can help the process of healing. Due to their excellent tissue adhesion, swelling, water absorption, bactericidal, and immune-regulating properties, polysaccharide-based bio-adhesive films have recently been investigated as intriguing alternatives in wound management. These films also mimic the structure of the skin and stimulate the regeneration of the skin. This review presented several design standards and functions of suitable bio-adhesive films for the healing of wounds. Additionally, the most recent developments in the use of bio-adhesive films as wound dressings based on polysaccharides, including hyaluronic acid, chondroitin sulfate, dextran, alginate, chitosan, cellulose, konjac glucomannan, gellan gum, xanthan gum, pectin, guar gum, heparin, arabinogalactans, carrageen, and tragacanth gum, are thoroughly discussed. Lastly, to create a road map for the function of polysaccharide-based bio-adhesive films in advanced wound care, their clinical performances and future challenges in making bio-adhesive films by three-dimensional bioprinting are summarized.

From Time to Timer in Wound Healing Through the Regeneration

Hard-to-heal wounds are an important public health issue worldwide, with a significant impact on the quality of life of patients. It is estimated that approximately 1-2% of the global population suffers from difficult wounds, which can be caused by a variety of factors such as trauma, infections, chronic diseases like diabetes or obesity, or poor health conditions. Hard-to-heal wounds are often characterized by a slow and complicated healing process, which can lead to serious complications such as infections, pressure ulcers, scar tissue formation, and even amputations. These complications can have a significant impact on the mobility, autonomy, and quality of life of patients, leading to an increase in healthcare and social costs associated with wound care. The preparation of the wound bed is a key concept in the management of hard-to-heal wounds, with the aim of promoting an optimal environment for healing. The TIME (Tissue, Infection/Inflammation, Moisture, Edge) model is a systematic approach used to assess and manage wounds in a targeted and personalized way. The concept of TIMER, expanding the TIME model, further focuses on regenerative processes, paying particular attention to promoting tissue regeneration and wound healing in a more effective and comprehensive way. The new element introduced in the TIMER model is "Regeneration", which highlights the importance of activating and supporting tissue regeneration processes to promote complete and lasting wound healing. Regenerative therapies can include a wide range of approaches, including cellular therapies, growth factors, bioactive biomaterials, stem cell therapies, and growth factor therapies. These therapies aim to promote the formation of new healthy tissues, reduce inflammation, improve vascularization, and stimulate cellular proliferation to accelerate wound closure and prevent complications. Thanks to continuous progress in research and development of regenerative therapies, more and more patients suffering from difficult wounds can benefit from innovative and promising solutions to promote faster and more effective healing, improve quality of life, and reduce the risk of long-term complications.

In vivo characterization of laser-assisted delivery of hyaluronic acid using multiphoton fluorescence lifetime imaging

Laser-assisted drug delivery (LADD) is a treatment method to enhance the penetration of pharmaceuticals through the skin. The aim of the present study is to track hyaluronic acid (HA) and analyse its effect on human skin in vivo after ablative fractional laser (AFL) treatment. Healthy male and female subjects were recruited. Four areas were marked on their forearms of each volunteer, and each area was assigned to one of the following treatment options: AFL + HA, AFL only, HA only or untreated control. A carbon dioxide laser was used for the AFL treatment. Follow-up measurements were scheduled 30 min and 30 days after treatment using multiphoton tomography equipped with fluorescence lifetime imaging (MPT-FLIM). A total of 11 subjects completed the study. By detecting fluorescence lifetimes, the HA and the anaesthetic ointment were clearly distinguishable from surrounding tissue. After AFL treatment, HA could be visualized in all epidermal and upper dermal layers. In contrast, HA in intact skin was only detected in the superficial layers at distinctly lower levels. The applied HA gel seemed to have beneficial properties for the wound healing process after laser treatment. LADD has proven to be a fast and effective method to increase HA uptake into the skin, allowing for improved hydration and skin rejuvenation over time. Furthermore, LADD could be a beneficial treatment option in laser resurfacing. MPT-FLIM proved to be an appropriate diagnostic tool for drug delivery tracking and monitoring of treatment response for individualized therapy adjustment.

In Situ Forming Bioartificial Hydrogels with ROS Scavenging Capability Induced by Gallic Acid Release with Potential in Chronic Skin Wound Treatment

In normal chronic wound healing pathways, the presence of strong and persistent inflammation states characterized by high Reactive Oxygen Species (ROS) concentrations is one of the major concerns hindering tissue regeneration. The administration of different ROS scavengers has been investigated over the years, but their effectiveness has been strongly limited by their short half-life caused by chronic wound environmental conditions. This work aimed at overcoming this criticism by formulating bioartificial hydrogels able to preserve the functionalities of the encapsulated scavenger (i.e., gallic acid-GA) and expand its therapeutic window. To this purpose, an amphiphilic poly(ether urethane) exposing -NH groups (4.5 × 1020 units/gpolymer) was first synthesized and blended with a low molecular weight hyaluronic acid. The role exerted by the solvent on system gelation mechanism and swelling capability was first studied, evidencing superior thermo-responsiveness for formulations prepared in saline solution compared to double demineralized water (ddH2O). Nevertheless, drug-loaded hydrogels were prepared in ddH2O as the best compromise to preserve GA from degradation while retaining gelation potential. GA was released with a controlled and sustained profile up to 48 h and retained its scavenger capability against hydroxyl, superoxide and 1'-diphenyl-2-picrylhydrazyl radicals at each tested time point. Moreover, the same GA amounts were able to significantly reduce intracellular ROS concentration upon oxidative stress induction. Lastly, the system was highly cytocompatible according to ISO regulation and GA-enriched extracts did not induce NIH-3T3 morphology changes.

Polysaccharide-based hydrogel promotes skin wound repair and research progress on its repair mechanism

Polysaccharides, being a natural, active, and biodegradable polymer, have garnered significant attention due to their exceptional properties. These properties make them ideal for creating multifunctional hydrogels that can be used as wound dressings for skin injuries. Polysaccharide hydrogel has the ability to both simulate the natural extracellular matrix, promote cell proliferation, and provide a suitable environment for wound healing while protecting it from bacterial invasion. Polysaccharide hydrogels offer a promising solution for repairing damaged skin. This review provides an overview of the mechanisms involved in skin damage repair and emphasizes the potential of polysaccharide hydrogels in this regard. For different skin injuries, polysaccharide hydrogels can play a role in promoting wound healing. However, we still need to conduct more research on polysaccharide hydrogels to provide more possibilities for skin damage repair.

Self-esterified hyaluronan hydrogels: Advancements in the production with positive implications in tissue healing

Hyaluronan-(HA) short half-life in vivo limits its benefits in tissue repair. Self-esterified-HA is of great interest because it progressively releases HA, promoting tissue-regeneration longer than the unmodified-polymer. Here, the 1-ethyl-3-(3-diethylaminopropyl)carbodiimide(EDC)-hydroxybenzotriazole(HOBt) carboxyl-activating-system was evaluated for self-esterifying HA in the solid state. The aim was to propose an alternative to the time-consuming, conventional reaction of quaternary-ammonium-salts of HA with hydrophobic activating-systems in organic media, and to the EDC-mediated reaction, limited by by-product formation. Additionally, we aimed to obtain derivatives releasing defined molecular-weight(MW)-HA that would be valuable for tissue renewal. A 250 kDa-HA(powder/sponge) was reacted with increasing EDC/HOBt amounts. HA-modification was investigated through Size-Exclusion-Chromatography-Triple-Detector-Array-analyses, FT-IR/¹H NMR and the products(XHAs) extensively characterized. Compared to conventional protocols, the set procedure is more efficient, avoids side-reactions, allows for an easier processing to diverse clinically-usable 3D-forms, leads to products gradually releasing HA under physiological conditions with the possibility to tune the MW of the biopolymer-released. Finally, the XHAs exhibit sound stability to Bovine-Testicular-Hyaluronidase, hydration/mechanical properties suitable for wound-dressings, with improvements over available matrices, and prompt in vitro wound-regeneration, comparably to linear-HA. To the best of our knowledge, the procedure is the first valid alternative to conventional protocols for HA self-esterification with advances in the process itself and in product performance.

Flavonoids as Potential Wound-Healing Molecules: Emphasis on Pathways Perspective

Wounds are considered to be a serious problem that affects the healthcare sector in many countries, primarily due to diabetes and obesity. Wounds become worse because of unhealthy lifestyles and habits. Wound healing is a complicated physiological process that is essential for restoring the epithelial barrier after an injury. Numerous studies have reported that flavonoids possess wound-healing properties due to their well-acclaimed anti-inflammatory, angiogenesis, re-epithelialization, and antioxidant effects. They have been shown to be able to act on the wound-healing process via expression of biomarkers respective to the pathways that mainly include Wnt/β-catenin, Hippo, Transforming Growth Factor-beta (TGF-β), Hedgehog, c-Jun N-Terminal Kinase (JNK), NF-E2-related factor 2/antioxidant responsive element (Nrf2/ARE), Nuclear Factor Kappa B (NF-κB), MAPK/ERK, Ras/Raf/MEK/ERK, phosphatidylinositol 3-kinase (PI3K)/Akt, Nitric oxide (NO) pathways, etc. Hence, we have compiled existing evidence on the manipulation of flavonoids towards achieving skin wound healing, together with current limitations and future perspectives in support of these polyphenolic compounds as safe wound-healing agents, in this review.

Polysaccharide-based hydrogels: New insights and futuristic prospects in wound healing

Polysaccharides elicit enormous and promising applications due to their extensive obtainability, innocuousness, and biodegradability. Various outstanding features of polysaccharides can be employed to fabricate biomimetic and multifunctional hydrogels as efficient wound dressings. These hydrogels mimic the natural extracellular matrix and also boost the proliferation of cells. Owing to distinctive architectures and abundance of functional groups, polysaccharide-derived hydrogels have exceptional physicochemical properties and unique therapeutic interventions. Hydrogels designed using polysaccharides can effectively safeguard wounds from bacterial attack. This review includes wound physiology and emphasises on numerous polysaccharide-based hydrogels for wound repair applications. Polysaccharide hydrogels for different wound types and diverse therapeutic agents loaded in hydrogels for wound repair with recent patents are portrayed in the current manuscript, debating the potential of fascinating hydrogels for effective wound healing. More research is required to engineer multifaceted advanced polysaccharide hydrogels with tuneable and adjustable properties to attain huge potential in wound healing.

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.

Protective Abilities of an Inhaled DPI Formulation Based on Sodium Hyaluronate against Environmental Hazards Targeting the Upper Respiratory Tract

The exposure of lung epithelium to environmental hazards is linked to several chronic respiratory diseases. We assessed the ability of an inhaled dry powder (DPI) medical device product (PolmonYDEFENCE/DYFESA^TM, SOFAR SpA, Trezzano Rosa, Italy), using a formulation of sodium hyaluronate (Na-Hya) as the key ingredient as a defensive barrier to protect the upper respiratory tract. Specifically, it was evaluated if the presence of the barrier formed by sodium hyaluronate present on the cells, reducing direct contact of the urban dust (UD) with the surface of cells can protect them in an indirect manner by the inflammatory and oxidative process started in the presence of the UD. Cytotoxicity and the protection capability against the oxidative stress of the product were tested in vitro using Calu-3 cells exposure to UD as a trigger for oxidative stress. Inflammation and wound healing were assessed using an air-liquid interface (ALI) culture model of the Calu-3 cells. Deposition studies of the formulation were conducted using a modified Anderson cascade impactor (ACI) and the monodose PillHaler^® dry powder inhaler (DPI) device, Na-Hya was detected and quantified using high-performance-liquid-chromatography (HPLC). Solubilised PolmonYDEFENCE/DYFESA^TM gives protection against oxidative stress in Calu-3 cells in the short term (2 h) without any cytotoxic effects. ALI culture experiments, testing the barrier-forming (non-solubilised) capabilities of PolmonYDEFENCE/DYFESA^TM, showed that the barrier layer reduced inflammation triggered by UD and the time for wound closure compared to Na-Hya alone. Deposition experiments using the ACI and the PillHaler^® DPI device showed that the majority of the product was deposited in the upper part of the respiratory tract. Finally, the protective effect of the product was efficacious for up to 24 h without affecting mucus production. We demonstrated the potential of PolmonYDEFENCE/DYFESA^TM as a preventative barrier against UD, which may aid in protecting the upper respiratory tract against environmental hazards and help with chronic respiratory diseases.

Amino Acid-Enriched Formula for the Post-Operative Care of Extraction Sockets Evaluated by 3-D Intraoral Scanning

Background: Hyaluronic acid and amino acids play an important role in the wound healing process, stimulating the development of the connective tissue and the activity and proliferation of fibroblasts. The aim of the present controlled clinical study was to evaluate the clinical efficacy of a topical gel formula containing hyaluronic acid and amino acids in terms of wound closure rate, painkiller intake, and patients’ reported pain and edema. Methods: This study included patients in need of a single tooth extraction. Patients were randomized into two groups with differing post-operative care regimens. Patients in the test group used the amino acid and hyaluronic acid-based gel, while the control group did not use any product. Each parameter was measured in both groups at different time points: immediately after surgery, and after 7, 14, 30, and 60 days. Results: A total of 40 patients (46.52 ± 9.84 years old) completed the observational period, and 40 extraction sockets were examined. After 7 days, the edema was significantly lower in the test group. The reported pain was lower in the test group without a significant difference, except for the first time point at 7 days. With the follow-up questionnaire, patients declared to have taken painkillers mainly during the first 7 days after surgery; however, the test group showed a lower need for painkillers than the control group. Conclusion: The post-operative and domiciliary use of an amino acid and hyaluronic acid-based gel for the management of soft tissue closure after tooth extraction is a valid coadjutant to reduce swelling, pain, and the need for painkillers. Additional studies are required to support the results of the present study.

Challenges in Healing Wound: Role of Complementary and Alternative Medicine

Although the word wound sounds like a simple injury to tissue, individual's health status and other inherent factors may make it very complicated. Hence, wound healing has gained major attention in the healthcare. The biology wound healing is precise and highly programmed, through phases of hemostasis, inflammation, proliferation and remodeling. Current options for wound healing which includes, use of anti-microbial agents, healing promoters along with application of herbal and natural products. However, there is no efficient evidence-based therapy available for specific chronic wounds that can result in definitive clinical outcomes. Under co-morbid conditions, chronic would poses numerous challenges. Use of Complementary and Alternative Medicines (CAMs) in health care sector is increasing and its applications in wound management remains like to "separate the diamonds from ore." Attempts have been made to understand the wound at the molecular level, mainly through the analysis of signature genes and the influence of several synthetic and natural molecules on these. We have outlined a review of challenges in chronic wound healing and the role of CAMs in chronic wound management. The main focus is on the applications and limitations of currently available treatment options for a non-healing wound and the best possible alternates to consider. This information generates broader knowledge on challenges in chronic wound healing, which can be further addressed using multidisciplinary approach and combination therapies.

Mobilizing Endogenous Repair Through Understanding Immune Reaction With Biomaterials

With few exceptions, humans are incapable of fully recovering from severe physical trauma. Due to these limitations, the field of regenerative medicine seeks to find clinically viable ways to repair permanently damaged tissue. There are two main approaches to regenerative medicine: promoting endogenous repair of the wound, or transplanting a material to replace the injured tissue. In recent years, these two methods have fused with the development of biomaterials that act as a scaffold and mobilize the body's natural healing capabilities. This process involves not only promoting stem cell behavior, but by also inducing activity of the immune system. Through understanding the immune interactions with biomaterials, we can understand how the immune system participates in regeneration and wound healing. In this review, we will focus on biomaterials that promote endogenous tissue repair, with discussion on their interactions with the immune system.

Phenol-Hyaluronic Acid Conjugates: Correlation of Oxidative Crosslinking Pathway and Adhesiveness

Hyaluronic acid (HA) is a natural polysaccharide with great biocompatibility for a variety of biomedical applications, such as tissue scaffolds, dermal fillers, and drug-delivery carriers. Despite the medical impact of HA, its poor adhesiveness and short-term in vivo stability limit its therapeutic efficacy. To overcome these shortcomings, a versatile modification strategy for the HA backbone has been developed. This strategy involves tethering phenol moieties on HA to provide both robust adhesiveness and intermolecular cohesion and can be used for oxidative crosslinking of the polymeric chain. However, a lack of knowledge still exists regarding the interchangeable phenolic adhesion and cohesion depending on the type of oxidizing agent used. Here, we reveal the correlation between phenolic adhesion and cohesion upon gelation of two different HA–phenol conjugates, HA–tyramine and HA–catechol, depending on the oxidant. For covalent/non-covalent crosslinking of HA, oxidizing agents, horseradish peroxidase/hydrogen peroxide, chemical oxidants (e.g., base, sodium periodate), and metal ions, were utilized. As a result, HA–catechol showed stronger adhesion properties, whereas HA–tyramine showed higher cohesion properties. In addition, covalent bonds allowed better adhesion compared to that of non-covalent bonds. Our findings are promising for designing adhesive and mechanically robust biomaterials based on phenol chemistry.

Non-inferiority study of the efficacy of two hyaluronic acid products in post-extraction sockets of impacted third molars

BACKGROUND

Hyaluronic acid (HA) is well known to exert an anti-inflammatory effect during oral wound healing and is commonly applied after tooth extraction. However, no double-blind randomized controlled study comparing two hyaluronate mouthwash products has been conducted so far. The aim of this study was to comparatively analyze the efficacy of Mucobarrier® and Aloclair® in terms of clinical symptoms.

RESULTS

A total of 112 patients were randomly assigned to assess the degree of discomfort, pain reduction, redness, burning sensation, and swelling between two groups on the day of surgery and 7 days later in a double blind test, with a total 56 Aloclair patients and 56 Mucobarrier patients. There was no statistically significant difference in the overall discomfort, degree of pain reduction, redness, burning sensation, and swelling between the Mucobarrier and Aloclair groups.

CONCLUSION

The local application of hyaluronic acid mouth wash after wisdom tooth extraction is beneficial in reducing overall discomfort and pain reduction, and the clinical utility of Mucobarrier® is no different from Aloclair®.

TRIAL REGISTRATION

Institutional Review Board of Yonsei University College of Dentistry, 2-2018-0036. Registered 10 September 2018-prospectively registered, https://eirb.yuhs.ac/.

Dual spinneret electrospun nanofibrous/gel structure of chitosan-gelatin/chitosan-hyaluronic acid as a wound dressing: In-vitro and in-vivo studies

Structural and compositional similarity to the natural extracellular matrix (ECM) is a main characteristic of an ideal scaffold for tissue regeneration. In order to resemble the fibrous/gel structure of skin ECM, a multicomponent scaffold was fabricated using biopolymers with structural similarity to ECM and wound healing properties i.e., chitosan (CS), gelatin (Gel) and hyaluronic acid (HA). The CS-Gel and CS-HA nanofibers were simultaneously electrospun on the collector through dual-electrospinning technique. The presence of polymers, possible interactions, and formation of polyelectrolyte complex were proven by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and thermogravimetric analysis (TGA). The noncomplex component of CS-HA fibers formed a gel state when the scaffold was exposed to the aqueous media, while the CS-Gel fibers reserved their fibrous structure, resulting in formation of fibrous/gel structure. The CS-Gel/CS-HA scaffold showed significantly higher cell proliferation (109%) in the first 24 h comparing with CS (90%) and CS-Gel (96%) scaffolds. Additionally, the initial cell adhesion improved by incorporation of HA. The in-vivo wound healing results in rat elucidated more wound healing capability of the CS-Gel/CS-HA scaffold in which new tissue with most similarity to the normal skin was formed.

Human-Derived Scaffold Components and Stem Cells Creating Immunocompatible Dermal Tissue Ensuing Regulated Nonfibrotic Cellular Phenotypes

Regeneration of large-sized acute and chronic wounds provoked by severe burns and diabetes is a major concern worldwide. The availability of immunocompatible matrix with a wide range of regenerative medical applications, more specifically, for nonhealing chronic wounds is an unmet clinical need. Extrapolating the in vitro tissue engineering knowledge for in vivo guided wound regeneration could be a meaningful approach. This study aimed to develop a completely human-derived and minimally immune-responsive scaffold comprising of acellular amniotic membrane (AM), fibrin (FIB) and hyaluronic acid (HA), termed AMFIBHA. The potential for in vivo guidance of skin regeneration was validated through in vitro dermal tissue assembly on the combination scaffold by growing human fibroblasts, differentiated from human adipose tissue-derived mesenchymal stem cells (hADMSCs). An effective method was standardized for obtaining decellularized amnion (dAM) for assuring better immuno-compatibility. The biochemical stability of dAM upon plasma sterilization (pdAM) confirms its suitability for both in vitro and in vivo tissue engineering. The problem of poor handling characteristics was solved by combining the dried dAM with fibrin derived from a clinically used fibrin sealant kit. An additional constituent HA, derived from human umbilical cord tissue, imparts the required water absorption and retention property for better cell migration and growth. Post sterilization, the combination scaffold AMFIBHA demonstrated hemo-/cytocompatibility, confirming the absence of detergent residuals. Upon long-term (20 days/40 days) culture of hADMSC-derived fibroblasts, the suppleness of generated tissue was established by demonstrating regulated deposition of collagen, elastin, and glycosaminoglycans using both qualitative and quantitative measurements. Regulated expressions of transforming growth factors-beta 1 (TGF-β1) & TGF-β3, alpha smooth muscle actin (α-SMA), fibrillin-1, collagen subtypes, and elastin suggest non-fibrotic fibroblast phenotype, which could be an effect of microenvironment endowed by the AM, FIB, and HA. In burn wound model experiments, immune response to cellular AM was prominent as compared to untreated/sham control wounds and decellularized AM-treated and AMFIBHA-treated wounds, ensuring biocompatibility. Wound regeneration with complete epithelialization, angiogenesis, development of rete pegs, and other skin appendages were clearly visualized in 28 days after treating large-sized (4 × 4 cm²), debrided, full-thickness third-degree burn wounds, indicating guided wound regeneration potential of AMFIBHA dermal substitute.

The role of oral formulation of hyaluronic acid and chondroitin sulphate for the treatment of the patients with laryngopharyngeal reflux

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Hyaluronan-Based Nanofibers: Fabrication, Characterization and Application

Nano- and microfibers based on biopolymers are some of the most attractive issues of biotechnology due to their unique properties and effectiveness. Hyaluronan is well-known as a biodegradable, naturally-occurring polymer, which has great potential for being utilized in a fibrous form. The obtaining of fibers from hyaluronan presents a major challenge because of the hydrophilic character of the polymer and the high viscosity level of its solutions. Electrospinning, as the advanced and effective method of the fiber generation, is difficult. The nano- and microfibers from hyaluronan may be obtained by utilizing special techniques, including binary/ternary solvent systems and several polymers described as modifying (or carrying), such as polyethylene oxide (PEO) and polyvinyl alcohol (PVA). This paper reviews various methods for the synthesis of hyaluronan-based fibers, and also collects brief information on the properties and biological activity of hyaluronan and fibrous materials based on it.

Effectiveness of hyaluronic acid gel (Jalosome soothing gel) for the treatment of radiodermatitis in a patient receiving head and neck radiotherapy associated with cetuximab: A case report and review

One of the principal side effects in patients that receive radiotherapy is radiodermatitis. Radiodermatitis can be highly invalidating for patients, causing pain, ulceration, swelling, and increased infection risk, with a negative effect on the quality of life, requiring dressings and medications. Therapeutic approaches reported so far in the literature have not proved to be effective in treating radiodermatitis. Therefore, new approaches are needed to deal with these side effects more effectively. The aim of the study was to evaluate the effectiveness of hyaluronic acid gel (HAG) (Jalosome soothing gel) for the treatment of a case of radiodermatitis. This is a case study of a patient affected by squamous cell carcinoma at the tongue base, who was treated with head and neck radiotherapy associated with the administration of cetuximab. About 1 month after this therapy was started the patient developed radiodermatitis, which did not regress with standard treatment. Therefore, HAG was applied once a day for about 20 days. The regression of radiodermatitis was measured using the Radiation Toxicity/Oncology Grading scale, pain relief was measured with a numerical scale, and patient satisfaction was done through a semi-structured interview. The patient presented a dramatic reduction of skin toxicity, which had been resistant to all previous therapeutic approaches. Pain, which was severe at the beginning, gradually disappeared. The patient showed great satisfaction for the reduction of pain and the regression of the radiodermatitis. The effectiveness of HAG appears to be promising for the treatment of radiodermatitis.

Efficacy of a repair cream based on Rhealba Oat plantlets extract and active healing compounds in peelings: benefit to patient's downtime and pain

BACKGROUND

The frequency of dermatological procedures is steadily increasing, accompanying a growing demand from patients. Chemical peels are a method of resurfacing in the treatment of various skin conditions. However, during the early healing process, patients may impose downtime on themselves. The erythema, pain and poor aesthetic appearance of the skin can lead to unwillingness to participate in social or professional activities.

OBJECTIVES

The objective of this study was to evaluate the tolerance and efficacy of a repair cream based on Rhealba Oat plantlets extract and active healing compounds after a peeling procedure.

METHODS

Men and women, aged 18-65 years, with Fitzpatrick phototype I-IV, who had previously received a medium-depth chemical peel on the face (TCA 30%) entered with their consent a clinical study evaluating the new test product based on Rhealba Oat and active healing compounds. At the beginning of the study, the selected patients received a TCA 30% medium-depth peel. Afterwards, they were treated during 29 days with the repair cream and evaluated for the benefits to downtime and pain.

RESULTS

Significant reductions of pain (P < 0.0114) and erythema (P < 0.0001) were observed in the study. The downtime reduction with the tested cream was 92% - from 9 days after the previous peeling procedure to 0.74 days with application of the tested cream - a difference of 8.39 days.

CONCLUSION

In consequence, the tested repair cream based on Rhealba Oat plantlets extract and active healing compounds brings clinical benefit to patients who undergo peeling procedures. By reducing pain and downtime, it allows patients to get back to their daily life activities a week earlier than with previous peels.

A Phase 2a, Multicenter, Randomized, Double-Blind, Parallel-Group, Placebo-Controlled Trial of IBD98-M Delayed-Release Capsules to Induce Remission in Patients with Active and Mild to Moderate Ulcerative Colitis

IBD98-M is a delayed-release formulation of mesalamine (mesalazine) and SH with a potential therapeutic role in ulcerative colitis (UC). A total of 51 patients with a modified Ulcerative Colitis Disease Activity Index (UCDAI) score of ≥4 and ≤10, and a modified UCDAI endoscopy subscore ≥1 were randomized for 6 weeks of double-blind treatment with IBD98 0.8 g/day or IBD 1.2 g/day or placebo. The efficacy and safety of IBD98-M in mild to moderate active UC were primarily evaluated. At week 6, 1 (5.9%), 2 (12.5%), and 2 (11.1%) patients receiving IBD98-M 0.8 g, IBD98-M 1.2 g, and placebo, respectively, (p > 0.999) achieved clinical remission. Higher clinical response was seen in IBD98-M 1.2 g (31.3%) versus placebo (16.7%) and endoscopic improvement in IBD98-M 0.8 g (29.4%) versus placebo (22.2%) was seen. Fecal calprotectin levels were reduced in IBD98-M groups versus placebo (p > 0.05). IBD98-M patients achieved significant improvement in physical health summary score component of the SF-36 (p = 0.01 and p = 0.03 respectively) compared to placebo. IBD98-M did not meet the primary end point but had higher clinical response (1.2 g/day) and endoscopic improvement (0.8 g/day) compared to placebo. The safety result shown that IBD98-M treatment was safe and well tolerated in this patient population. No new safety signals or unexpected safety findings were observed during the study. Further trials with different stratification and longer follow-up may be needed to evaluate the efficacy.

MitoQ Loaded Chitosan-Hyaluronan Composite Membranes for Wound Healing

Two self-associating biopolymers, namely chitosan (Ch) and a high-molar-mass hyaluronan (HA), were used to prepare membranes with the aim to protect and to enhance the healing of injured skin. A mitochondrially-targeted antioxidant-MitoQ-was incorporated into the mixture of biopolymers prior to their self-association. These three-component membranes were evaluated in detail utilising surface roughness measurements, contact angle measurements, hemocompatibility, and thrombogenicity analyses. Furthermore, in vivo application of Ch/HA/MitoQ membranes was assessed on injured rabbit and rat skin utilizing histological methods. The results showed that the prepared thrombogenic Ch/HA/MitoQ membranes had higher roughness, which allowed for greater surface area for tissue membrane interaction during the healing processes, and lower cytotoxicity levels than controls. MitoQ-loaded composite membranes displayed superior healing properties in these animal models compared to control membranes.

Scarless wound healing: Transitioning from fetal research to regenerative healing

Since the discovery of scarless fetal skin wound healing, research in the field has expanded significantly with the hopes of advancing the finding to adult human patients. There are several differences between fetal and adult skin that have been exploited to facilitate scarless healing in adults including growth factors, cytokines, and extracellular matrix substitutes. However, no one therapy, pathway, or cell subtype is sufficient to support scarless wound healing in adult skin. More recently, products that contain or mimic fetal and adult uninjured dermis were introduced to the wound healing market with promising clinical outcomes. Through our review of the major experimental targets of fetal wound healing, we hope to encourage research in areas that may have a significant clinical impact. Additionally, we will investigate therapies currently in clinical use and evaluate whether they represent a legitimate advance in regenerative medicine or a vulnerary agent. WIREs Dev Biol 2018, 7:e309. doi: 10.1002/wdev.309 This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Regeneration Plant Development > Cell Growth and Differentiation Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells.

Solubilized Amnion Membrane Hyaluronic Acid Hydrogel Accelerates Full-Thickness Wound Healing

The early and effective treatment of wounds is vital to ensure proper wound closure and healing with appropriate functional and cosmetic outcomes. The use of human amnion membranes for wound care has been shown to be safe and effective. However, the difficulty in handling and placing thin sheets of membrane, and the high costs associated with the use of living cellularized tissue has limited the clinical application of amniotic membrane wound healing products. Here, we describe a novel amnion membrane-derived product, processed to result in a cell-free solution, while maintaining high concentrations of cell-derived cytokines and growth factors. The solubilized amnion membrane (SAM) combined with the carrier hyaluronic acid (HA) hydrogel (HA-SAM) is easy to produce, store, and apply to wounds. We demonstrated the efficacy of HA-SAM as a wound treatment using a full-thickness murine wound model. HA-SAM significantly accelerated wound closure through re-epithelialization and prevented wound contraction. HA-SAM-treated wounds had thicker regenerated skin, increased total number of blood vessels, and greater numbers of proliferating keratinocytes within the epidermis. Overall, this study confirms the efficacy of the amnion membrane as a wound treatment/dressing, and overcomes many of the limitations associated with using fresh, cryopreserved, or dehydrated tissue by providing a hydrogel delivery system for SAM. Stem Cells Translational Medicine 2017;6:2020-2032.

Flexible and highly interconnected, multi-scale patterned chitosan porous membrane produced in situ from mussel shell to accelerate wound healing

Utilization of the underlying mechanisms of biological systems is the principal endeavor of biomimetics, the primary goal of which is to treat on-going biological processes. From the perspective of tissue engineering, one purpose of biomimetics is to create highly cellular- or tissue-favored environments for bio-defect repair. Marine creatures such as mussels have inspired bioengineers to design ideal cellular substrates, strong adhesives, and other bioengineering materials. Herein, we report a novel mussel shell-derived membrane for wound dressing. Mussel shell in situ manufactured a highly flexible membrane with a regular porous pattern after the direct action of acid (A-shell) followed by base treatment (B-shell). The SEM images display elegantly patterned polygons with nanowalls (about 710 nm). Compared with the A-shell, the B-shell has a more defined and flexible structure. FTIR characterization of the structures indicates that deacetylation occurred on the B-shell. A cellular toxicity study was conducted to determine the optimized processing parameters before applying the wound healing model. The B-shell significantly closed the wound at an early stage (day 10) followed by complete contraction at a later stage (day 21). This is completely consistent with the higher level of α-SMA protein, which accelerates wound contraction in the wound sites. As a key index of the integration between host and guest, a high blood vessel density was detected in both the A-shell and B-shell groups. The treated shells can improve epidermal migration, the formation of granulation tissue, neovascularization and hair follicles, and reduce scar tissue. Our mussel shell-derived membrane could have potential as a wound dressing and other biomedical uses.

Polysaccharide Fabrication Platforms and Biocompatibility Assessment as Candidate Wound Dressing Materials

Wound dressings are critical for wound care because they provide a physical barrier between the injury site and outside environment, preventing further damage or infection. Wound dressings also manage and even encourage the wound healing process for proper recovery. Polysaccharide biopolymers are slowly becoming popular as modern wound dressings materials because they are naturally derived, highly abundant, inexpensive, absorbent, non-toxic and non-immunogenic. Polysaccharide biopolymers have also been processed into biomimetic platforms that offer a bioactive component in wound dressings that aid the healing process. This review primarily focuses on the fabrication and biocompatibility assessment of polysaccharide materials. Specifically, fabrication platforms such as electrospun fibers and hydrogels, their fabrication considerations and popular polysaccharides such as chitosan, alginate, and hyaluronic acid among emerging options such as arabinoxylan are discussed. A survey of biocompatibility and bioactive molecule release studies, leveraging polysaccharide's naturally derived properties, is highlighted in the text, while challenges and future directions for wound dressing development using emerging fabrication techniques such as 3D bioprinting are outlined in the conclusion. This paper aims to encourage further investigation and open up new, disruptive avenues for polysaccharides in wound dressing material development.

A single center, pilot, double-blinded, randomized, comparative, prospective clinical study to evaluate improvements in the structure and function of facial skin with tazarotene 0.1% cream alone and in combination with GliSODin(®) Skin Nutrients Advanced Anti-Aging Formula

Background

Superoxide dismutase (SOD) reduces the reactive oxygen species formation associated with oxidative stress. An imbalance between free radicals and antioxidants can lead to accelerated aging. GliSODin^® Skin Nutrients Advanced Anti-Aging Formula (GAAF) is an SOD-containing dietary nutricosmetic formulated with other nutraceuticals that promote improvements in the structure and function of the skin, including hydration, elasticity, structural integrity, and photoaging caused by oxidative stress. Tazarotene cream 0.1% (TAZ) is a United States Food and Drug Administration-approved drug indicated for use in the mitigation of facial fine wrinkling, facial mottled hyper- and hypopigmentation, and benign facial lentigines when taken in conjunction with a comprehensive skin care and sun avoidance program.

Objective

To determine if the antioxidant, anti-aging, hydrating and skin-rejuvenating properties of GAAF complement the retinoic actions of TAZ to improve the structure and function of facial skin.

Method

A 90-day comparative study of ten subjects with facial photodamage; daily topical application of TAZ was used in combination with three capsules of GAAF (780 mg each) or placebo orally, with food, per the randomization allocation.

Results

After 90 days of treatment, TAZ alone and in combination with GAAF improved fine wrinkles (↓1.2 versus 2.0), mottled hyperpigmentation (↓2.2 versus 2.8) and overall photodamage (↓1.0 versus 1.8), as well as patient-reported response to treatment (↓2.0 versus 1.6). At week 12, TAZ/GAAF combination treatment (Group A) versus TAZ treatment alone (Group C) was of significant clinical benefit, with respect to fine wrinkling (14.7%/41.7%), overall photodamage (15.6%/53.0%), skin moisture (19.1%/103.2%), skin elasticity (12.8%/87.7%), and response to treatment (8.8%/21.4%).

Conclusion

The study suggests GAAF in combination with TAZ is safe and provides significant clinical benefit with relative improvement in facial fine wrinkling, overall photodamage, skin moisture and elasticity.

Spontaneous clostridial myonecrosis after pregnancy - emergency treatment to the limb salvage and functional recovery: a case report

Clostridial myonecrosis (CM) is a rare, life threatening necrotizing infection of a skeletal muscle caused by Clostridium perfringens in the majority of cases. The diagnosis may be difficult because of few diagnostic and cutaneous signs early in its course. Standard therapy involves surgical debridements of a devitalized tissue and high-dose organism-specific antibiotic therapy. The hyperbaric oxygen has also showed its usefulness in the treatment of these infections. Autograft systems as tissue replacement, based on bioengineered materials, have been demonstrated to be safe and effective treatments for chronic wounds and a suitable physiotherapy is recommended for the recovery of functional impairments of upper extremities. We present a rare case of CM of right upper limb treated with a combination of standard treatments and new techniques.

Limb trauma: the use of an advanced wound care device in the treatment of full-thickness wounds

This is an observational case series of 15 patients with full-thickness traumatic wound defects treated with a dermal substitute. There were 8 male and 7 female patients with a mean age of 36.6 years. Eight patients had trauma to the lower limbs and 7 were of the upper limbs, with the average lesion size 104.4 cm² (range 6–490 cm²). The time to complete healing had a mean average time of 26.8 days (range 16–60 days). All patients went on to successful repair with 6 patients requiring a second application of the substitute and 5 patients needing split thickness skin grafts. Infection was recorded in one patient.

Effects of hyaluronic acid conjugation on anti-TNF-α inhibition of inflammation in burns

Biomaterials capable of neutralizing specific cytokines could form the basis for treating a broad range of conditions characterized by intense, local inflammation. Severe burns, spanning partial- to full-thickness of the dermis, can result in complications due to acute inflammation that contributes to burn progression, and early mediation may be a key factor in rescuing thermally injured tissue from secondary necrosis to improve healing outcomes. In this work, we examined the effects on burn progression and influence on the inflammatory microenvironment of topical application of anti-tumor necrosis factor-α (anti-TNF-α) alone, mixed with hyaluronic acid (HA) or conjugated to HA. We found that non-conjugated anti-TNF-α decreased macrophage infiltration to a greater extent than that conjugated to HA; however, there was little effect on the degree of progression or IL-1β levels. A simple transport model is proposed to analyze the results, which predicts qualitative and quantitative differences between untreated burn sites and those treated with the conjugates. Our results indicate that conjugation of anti-TNF-α to high molecular weight HA provides sustained, local modulation of the post-injury inflammatory responses compared to direct administration of non-conjugated antibodies.

Effects of a cross-linked hyaluronic acid based gel on the healing of open wounds in dogs

OBJECTIVE

To compare effects of a cross-linked hyaluronic acid (HA) based gel (CMHA-S) to a standard wound management protocol on the healing of acute, full-thickness wounds in dogs.

STUDY DESIGN

A prospective, controlled, experimental study.

ANIMALS

Purpose-bred, adult, female beagles (n = 10).

METHODS

Two 2 × 2 cm wounds were surgically created bilaterally on the trunk of each dog and each side randomized to treatment (CMHA-S) or control (CON) groups. Total and open wound areas were measured with digital image planimetry at 15 time points. From these data, percent contraction and percent epithelialization were calculated. Tissue biopsies were obtained at 6 time points and histologic features were scored.

RESULTS

Total wound area was significantly larger and percent contraction was significantly less in CMHA-S compared to CON wounds at all data points between days 9 and 18. At day 25, and for the remainder of the study, CMHA-S wounds were smaller and contracted more than CON wounds, reaching significance at day 32. Percent epithelialization was significantly less in CMHA-S compared to CON wounds at all data points after day 11. Histologically, fibroblastic cellular infiltration was significantly higher in CMHA-S wounds at day 21.

CONCLUSIONS

CMHA-S wounds healed more slowly than CON wounds. This HA-based gel is not indicated in acute, full-thickness skin wounds in dogs as administered in this study. However, treatment may be beneficial in the mid-to-late repair stage of healing, or if scar minimization is desired. Further studies to evaluate the effects of the CMHA-S gel on canine wounds are indicated.

Tissue-engineered provisional matrix as a novel approach to enhance diabetic wound healing

Inherent pathologies associated with diabetic wound microenvironment including increased proteolysis, inflammatory dysregulation, and impaired neovascularization prevent timely resolution of chronic diabetic ulcers. It is hypothesized that augmentation of local wound microenvironment with a stable provisional matrix formed by proteolysis-resistant angiogenic peptide nanofibers (NFs) will create permissive environment for attenuated inflammation, enhanced neovascularization, and improved diabetic wound healing. Using murine excisional wound healing models, full-thickness dorsal skin wounds were treated with either NFs or control solutions (phosphate buffered saline; hyaluronic acid) and analyzed for morphology, inflammatory response, neovascularization, and biomechanical properties. NF treatment of diabetic wounds stimulated formation of a robust pro-angiogenic in situ tissue-engineered provisional matrix leading to a significant decrease in wound inflammatory cell infiltration and proinflammatory interleukin-6 levels, a significant increase in endothelial and endothelial progenitor cell infiltration, vascular endothelial growth factor levels, and neovascularization (day 7), as well as improved wound morphology, accelerated wound closure, and significantly stronger repair tissue (day 28). These results suggest that appropriate design of provisional matrix may compensate for some of the complex disruptions in diabetic wound microenvironment and provide missing cues to cells and direct in situ responses toward improved healing, which is promising for future development of new therapies for diabetic ulcers.