Inflammatory cytokine levels in chronic venous insufficiency ulcer tissue before and after compression therapy

Extracellular matrix-inspired biomaterials for wound healing

Diabetic foot ulcers (DFU) are a debilitating and life-threatening complication of Diabetes Mellitus. Ulceration develops from a combination of associated diabetic complications, including neuropathy, circulatory dysfunction, and repetitive trauma, and they affect approximately 19-34% of patients as a result. The severity and chronic nature of diabetic foot ulcers stems from the disruption to normal wound healing, as a result of the molecular mechanisms which underly diabetic pathophysiology. The current standard-of-care is clinically insufficient to promote healing for many DFU patients, resulting in a high frequency of recurrence and limb amputations. Biomaterial dressings, and in particular those derived from the extracellular matrix (ECM), have emerged as a promising approach for the treatment of DFU. By providing a template for cell infiltration and skin regeneration, ECM-derived biomaterials offer great hope as a treatment for DFU. A range of approaches exist for the development of ECM-derived biomaterials, including the use of purified ECM components, decellularisation and processing of donor/ animal tissues, or the use of in vitro-deposited ECM. This review discusses the development and assessment of ECM-derived biomaterials for the treatment of chronic wounds, as well as the mechanisms of action through which ECM-derived biomaterials stimulate wound healing.

Compression Therapy in Dermatology

The benefit of lower limb compression therapy is not limited to chronic venous insufficiency or/and lymphoedema. Thanks to its anti-edema and anti-inflammatory effects, compression therapy is considered a beneficial adjuvant therapy to treat atypical wounds, inflammatory dermatoses, cellulitis, and traumatic wounds in the absence of contraindications. Strict contraindications are limited to severe peripheral arterial disease and decompensated heart failure. The variability of commercially available compression materials and systems, such as short-stretch bandages, multi-component systems, zinc oxide bandages, medical adaptive compression systems, ulcer compression stockings or medical compression stockings, facilitates the adaptation of compression therapy to the individual needs of each patient. Compared to venous leg ulcers, low pressures of 20mmHg are often sufficient to treat dermatological disorders, with higher patient tolerance and compliance.

Benefits of an Adjustable Compression Garment System for the Reduction of Chronic Leg Oedema (ACROE Study)

OBJECTIVE

This study aimed to assess whether a specific adjustable compression garment (ACG) system (Coolflex Standard Calf and Coolflex Standard Foot; Sigvaris Inc.) promotes self-care in patients with chronic leg oedema. Secondary aims were to assess the effectiveness of this ACG in reducing oedema, improving patient reported outcomes, and determining the patients' degree of satisfaction with the handling of the wrap.

METHODS

This was a multicentre prospective observational study. The study included 99 adult patients aged 18 - 90 years presenting with chronic oedema of the lower extremity, which encompasses conditions such as lymphoedema, venous oedema, and phlebolymphoedema. At baseline, all patients received an ACG. After two to three days and after six weeks, their overall satisfaction with the therapy was assessed. Leg volume was determined in a contactless manner during the baseline and follow up visits. All patients completed the cross cultural adaptation of the Lymphoedema Functioning, Disability and Health Questionnaire for Patients with Lymphoedema of the Lower Extremity in Germany (Lymph-ICF-UG).

RESULTS

A total of 86 patients completed the study and were followed up for six weeks. At the final six week follow up, 82 (95.3%) of the 86 subjects indicated that they were able to put on the wrap independently or with a little help from relatives. The overall satisfaction rate was 88.0% (95% confidence interval [CI], 79.64 - 93.9%). The mean leg volume reduction from baseline to six weeks was -4.7% (95% CI -6.3 - -3.0%; p < .001). Lymph-ICF-UG scores and scores in all domains improved significantly from baseline to the final follow up.

CONCLUSION

The ACG used in this study was found to promote self-care in a high proportion of patients with chronic leg oedema. A significant reduction in oedema was observed.

Comparative analysis of electrochemical and optical sensors for detection of chronic wounds biomarkers: A review

Chronic wounds (CW) present a significant healthcare challenge due to their prolonged healing time and associated complications. To effectively treat these wounds and prevent further deterioration, monitoring their healing progress is crucial. Traditional wound assessment methods relying on visual inspection and subjective evaluation are prone to inter-observer variability. Biomarkers play a critical role in objectively evaluating wound status and predicting healing outcomes, providing quantitative measures of wound healing progress, inflammation, infection, and tissue regeneration. Recent attention has been devoted to identifying and validating CW biomarkers. Various studies have investigated potential biomarkers, including growth factors, cytokines, proteases, and extracellular matrix components, shedding light on the complex molecular and cellular processes within CW. This knowledge enables a more targeted and personalized approach to wound management. Accurate and sensitive techniques are necessary for detecting CW biomarkers. Thus, this review compares and discusses the use of electrochemical and optical sensors for biomarker determination. The advantages and disadvantages of these sensors are highlighted. Differences in detection capabilities and characteristics such as non-invasiveness, portability, high sensitivity, specificity, simplicity, cost-effectiveness, compatibility with point-of-care applications, and real-time monitoring of wound biomarkers will be pointed out and compared. In summary, this work provides an overview of CW, explores the emerging field of CW biomarkers, and discusses methods for detecting these biomarkers, with a specific focus on optical and electrochemical sensors. The potential of further research and development in this field for advancing wound care and improving patient outcomes will also be noted.

Bacterial Biofilm in Chronic Wounds and Possible Therapeutic Approaches

Wound repair and skin regeneration is a very complex orchestrated process that is generally composed of four phases: hemostasis, inflammation, proliferation, and remodeling. Each phase involves the activation of different cells and the production of various cytokines, chemokines, and other inflammatory mediators affecting the immune response. The microbial skin composition plays an important role in wound healing. Indeed, skin commensals are essential in the maintenance of the epidermal barrier function, regulation of the host immune response, and protection from invading pathogenic microorganisms. Chronic wounds are common and are considered a major public health problem due to their difficult-to-treat features and their frequent association with challenging chronic infections. These infections can be very tough to manage due to the ability of some bacteria to produce multicellular structures encapsulated into a matrix called biofilms. The bacterial species contained in the biofilm are often different, as is their capability to influence the healing of chronic wounds. Biofilms are, in fact, often tolerant and resistant to antibiotics and antiseptics, leading to the failure of treatment. For these reasons, biofilms impede appropriate treatment and, consequently, prolong the wound healing period. Hence, there is an urgent necessity to deepen the knowledge of the pathophysiology of delayed wound healing and to develop more effective therapeutic approaches able to restore tissue damage. This work covers the wound-healing process and the pathogenesis of chronic wounds infected by biofilm-forming pathogens. An overview of the strategies to counteract biofilm formation or to destroy existing biofilms is also provided.

[Compression therapy for inflammatory dermatoses of the legs]

In addition to venous and lymphatic diseases, there is increasing scientific evidence that inflammatory dermatoses of the legs are also indications for compression therapy. Specifically, diseases such as pyoderma gangrenosum, livedoid vasculopathy, cutaneous vasculitides, necrobiosis lipoidica, psoriasis, or erysipelas are conditions for which adjunctive compression therapy may be used when manifestations occur on the lower extremities. When inflammatory dermatoses are accompanied by edema, compression therapy is not an off-label use. Especially because of the often problematic pain symptoms, compression therapy can be performed with low resting pressures around 20 mmHg, especially in inflammatory dermatoses.In this review article, the current scientific aspects of compression therapy in inflammatory dermatoses of the legs and the corresponding limitations are presented in a differentiated manner.

Hydrogel dressings with intrinsic antibiofilm and antioxidative dual functionalities accelerate infected diabetic wound healing

Chronic wounds are often infected with biofilm bacteria and characterized by high oxidative stress. Current dressings that promote chronic wound healing either require additional processes such as photothermal irradiation or leave behind gross amounts of undesirable residues. We report a dual-functionality hydrogel dressing with intrinsic antibiofilm and antioxidative properties that are synergistic and low-leaching. The hydrogel is a crosslinked network with tethered antibacterial cationic polyimidazolium and antioxidative N-acetylcysteine. In a murine diabetic wound model, the hydrogel accelerates the closure of wounds infected with methicillin-resistant Staphylococcus aureus or carbapenem-resistant Pseudomonas aeruginosa biofilm. Furthermore, a three-dimensional ex vivo human skin equivalent model shows that N-acetylcysteine promotes the keratinocyte differentiation and accelerates the re-epithelialization process. Our hydrogel dressing can be made into different formats for the healing of both flat and deep infected chronic wounds without contamination of the wound or needing other modalities such as photothermal irradiation.

The effect of medical grade compression garments on the repeated-bout effect in non-resistance-trained men

NEW FINDINGS

What is the central question of this study? What are the effects of compression garments on recovery from unaccustomed damaging exercise and subsequent protective adaptations? What is the main finding and its importance? Compression did not influence recovery, but was associated with blunted protective adaptations for isokinetic performance, which were completely absent at high velocities. Based on these findings, the use of compression garments for recovery would not be recommended following unaccustomed exercise, particularly if the maintenance of high-velocity performance following exercise-induced muscle damage is desirable.

ABSTRACT

Whilst compression garments (CG) may enhance recovery from exercise-induced muscle damage (EIMD), many recovery strategies can attenuate adaptative responses. Therefore, the effects of CG on recovery from EIMD, and the rapid protective adaptations known as the repeated bout effect (RBE) were investigated. Thirty-four non-resistance-trained males (18-45 years) randomly received class II medical-grade CG or placebo for 72 h following eccentrically-focused lower-body exercise, in a double-blind, randomised controlled trial. Indices of EIMD were assessed at baseline, 0, 24, 48 and 72 h post-exercise, before exercise and testing were repeated after 14 days. Results were analysed using a three-way (time × condition × bout) linear mixed-effects model. Exercise impaired isometric and isokinetic strength, with soreness and thigh circumference elevated for 72 h (P < 0.001). Compression did not enhance recovery (P > 0.05), despite small to moderate effect sizes (ES, reported alongside 90% confidence intervals) for isokinetic strength (ES from 0.2 [-0.41, 0.82] to 0.65 [0.03, 1.28]). All variables recovered faster after the repeated bout (P < 0.005). However, RBE for peak isokinetic force was impaired in CG at 60° s-1 (group × bout interaction: χ2  = 4.24, P = 0.0395; ES = -0.56 [-1.18, 0.07]) and completely absent at 120° s-1 (χ2  = 16.2, P < 0.001, ES = -0.96 [-1.61, -0.32]) and 180° s-1 (χ2  = 10.4, P = 0.001, ES = -0.72 [-1.35, -0.09]). Compression blunted RBE at higher isokinetic velocities without improving recovery in non-resistance-trained males, potentially contraindicating their use following unaccustomed exercise in this population.

Primary Care Disease Management for Venous Leg Ulceration in German Healthcare: Results of the Ulcus Cruris Care Pilot Study

Despite proven effectiveness, compression therapy is applied in only 20-40% of patients with venous leg ulceration, leading to avoidable chronification and morbidity. The Ulcus Cruris Care project was established to develop a new disease-management concept comparable to existing programs for chronic diseases to support evidence-based treatment of venous leg ulceration. This prospective controlled study assessed its first implementation. Interventional elements comprised online training for general practitioner practices, software support for case management, and educational materials for patients. A total of 20 practices and 40 patients were enrolled in a 1:1 ratio to the intervention and control group. Guideline-conform compression therapy was applied more frequently in the intervention group (19/20 [95%] vs. 11/19 [58%]; p = 0.006). For patients with ulcers existing ≤ 6 months, the healing rate at 12 weeks was 8/11 [73%] (intervention) compared to 4/11 [36%] (control; p = 0.087). Patients after intervention had higher scores for self-help and education in the PACIC-5A questionnaire (42.9 ± 41.6 vs. 11.4 ± 28.8; p = 0.044). Treatment costs were EUR 1.380 ± 1.347 (intervention) and EUR 2.049 ± 2.748 (control; p = 0.342). The results of this study indicate that the Ulcus Cruris Care intervention may lead to a significant improvement in care. Consequently, a broader rollout in German healthcare seems warranted.

Compression therapy in dermatology

Compression therapy is a conservative therapy that can be used in many patients with dermatological conditions, especially those associated with edema. In addition to its well-established use in venous and lymphatic disorders, there is increasing evidence that compression therapy supports the healing of inflammatory dermatoses. The presence of edema, regardless of its etiology, is an indication for the use of compression therapy. Nowadays, a variety of materials and treatment options are available for compression therapy, each with their own advantages and disadvantages. Often, compression therapy with low resting pressures is sufficient for effective therapy and is better tolerated by patients. The main contraindications to compression therapy are advanced peripheral arterial disease and decompensated heart failure. Individual factors and economic considerations should be taken into account when deciding on compression therapy with the patient. Patient self-management should be encouraged whenever possible. This requires education and support tools.

Pyoderma Gangrenosum: Treatment Options

Pyoderma gangrenosum is a rare neutrophilic dermatosis that leads to exceedingly painful ulcerations of the skin. Although the exact pathogenesis is not yet fully understood, various auto-inflammatory phenomena with increased neutrophil granulocyte activity have been demonstrated. Despite the limited understanding of the pathogenesis, it is no longer a diagnosis of exclusion, as it can now be made on the basis of validated scoring systems. However, therapy remains a major multidisciplinary challenge. Various immunosuppressive and immunomodulatory therapies are available for the treatment of affected patients. In addition, concomitant topical pharmacologic therapy, wound management and pain control should always be addressed. Corticosteroids and/or cyclosporine remain the systemic therapeutics of choice for most patients. However, in recent years, there has been an increasing number of studies on the positive effects of biologic therapies such as inhibitors of tumour necrosis factor-α; interleukin-1, interleukin-17, interleukin-23 or complement factor C5a. Biologics have now become the drug of choice in certain scenarios, particularly in patients with underlying inflammatory comorbidities, and are increasingly used at an early stage in the disease rather than in therapy refractory patients.

Kompressionstherapie in der Dermatologie

Die Kompressionstherapie ist eine konservative Therapie, die bei vielen Patienten mit dermatologischen Krankheiten durchgeführt werden kann, insbesondere wenn diese mit Ödemen assoziiert sind. Neben den wissenschaftlich sehr gut belegten Indikationen bei venösen und lymphatischen Erkrankungen, gibt es auch zunehmend wissenschaftliche Hinweise, dass durch die Kompressionstherapie die Abheilung entzündlicher Dermatosen unterstützt wird. Wenn Ödeme vorliegen, handelt es sich, unabhängig von deren Genese, um einen Einsatz im Rahmen der Zulassung der Kompressionstherapie.

Für die Kompressionstherapie stehen heute verschiedene Materialien und Versorgungsoptionen mit systemspezifischen Vor‐ und Nachteilen zur Verfügung. Oft ist eine Kompressionstherapie mit niedrigen Ruhedruckwerten für einen Therapieerfolg ausreichend und wird von den Patienten besser toleriert. Als wichtigste Kontraindikationen der Kompressionstherapie sind die fortgeschrittene periphere arterielle Verschlusskrankheit und die dekompensierte Herzinsuffizienz zu beachten.

Bei der gemeinsam mit dem Patienten getroffenen Entscheidung für eine Kompressionstherapie, sollten individuelle Faktoren und wirtschaftliche Aspekte berücksichtigt werden. Wann immer möglich, ist ein Selbstmanagement des Patienten zu unterstützen. Hierfür sind Edukation und Hilfsmittel erforderlich.

Microenvironment responsive nanocomposite hydrogel with NIR photothermal therapy, vascularization and anti-inflammation for diabetic infected wound healing

Bacterial infection, excessive inflammation and damaging blood vessels network are the major factors to delay the healing of diabetic ulcer. At present, most of wound repair materials are passive and can't response to the wound microenvironment, resulting in a low utilization of bioactive substances and hence a poor therapeutic effect. Therefore, it's essential to design an intelligent wound dressing responsive to the wound microenvironment to achieve the release of drugs on-demand on the basis of multifunctionality. In this work, metformin-laden CuPDA NPs composite hydrogel (Met@ CuPDA NPs/HG) was fabricated by dynamic phenylborate bonding of gelatin modified by dopamine (Gel-DA), Cu-loaded polydopamine nanoparticles (CuPDA NPs) with hyaluronic acid modified by phenyl boronate acid (HA-PBA), which possessed good injectability, self-healing, adhesive and DPPH scavenging performance. The slow release of metformin was achieved by the interaction with CuPDA NPs, boric groups (B-N coordination) and the constraint of hydrogel network. Metformin had a pH and glucose responsive release behavior to treat different wound microenvironment intelligently. Moreover, CuPDA NPs endowed the hydrogel excellent photothermal responsiveness to kill bacteria of >95% within 10 min and also the slow release of Cu²⁺ to protect wound from infection for a long time. Met@ CuPDA NPs/HG also recruited cells to a certain direction and promoted vascularization by releasing Cu²⁺. More importantly, Met@CuPDA NPs/HG effectively decreased the inflammation by eliminating ROS and inhibiting the activation of NF-κB pathway. Animal experiments demonstrated that Met@CuPDA NPs/HG significantly promoted wound healing of diabetic SD rats by killing bacteria, inhibiting inflammation, improving angiogenesis and accelerating the deposition of ECM and collagen. Therefore, Met@CuPDA NPs/HG had a great application potential for diabetic wound healing.

How to Evaluate and Choose the Proper Treatments for Patients with Lower Extremity Venous Disease

With an increasing number of interventional and noninterventional treatment options available for venous disorders, it is important that patients undergo a thorough and systematic evaluation. Clinical evaluation should include a personal and family history of venous thromboembolism (VTE), varicose veins, and thrombophilia as these factors affect response and recurrence of disease. Patient should undergo diagnostic and quality of life assessment using validated tools to monitor response to treatment. Duplex ultrasound, both deep and superficial veins, documenting both obstruction and reflux is initial imaging with CT and MRI indicated to document pelvic, iliac vein, and IVC patency and pathology. Conservative therapy including compression, healthy lifestyle with diet, and exercise. New and novel interventional therapies are available for patients with venous disease with recent randomized controlled trials and multisocietal guidelines providing evidence-based recommendations for patients with superficial and deep venous disease. Since the use of anticoagulant and antiplatelet therapies post venous intervention is not well studied nor standardized, patients should routinely undergo evaluation for ongoing risk of recurrent thrombosis and stent occlusion. Finally, patients should be counseled that superficial and deep venous disease is a chronic and often progressive disease, and follow-up at least annually is recommended.

[Randomized clinical trial of compression therapy of the lower legs in patients with psoriasis]

BACKGROUND

Psoriatic plaques at the distal lower extremities are notoriously treatment resistant. Medical compression therapy could potentially be a useful supplementary therapeutic measure at this site. However, there is concern that the Koebner phenomenon may cause a worsening of the skin condition. Therefore, the purpose of this study was to investigate the effects of compression therapy on psoriatic plaques in the presence of coexisting edema of the lower legs.

PATIENTS AND METHODS

Compression therapy was performed in addition to standard of care on one lower leg for 4 weeks (half-side test) in patients with psoriatic plaques and edema on both lower legs. The primary endpoint of the study was clinical response of the psoriatic plaques on the lower legs measured with the lesion severity score (LSS) and the locally affected body surface area in a side-by-side comparison at week 4 compared with baseline. Secondary endpoints were related to patient-reported outcomes.

RESULTS

Data from 30 patients were included in the analysis. In the descriptive analysis, the mean LSS results and the subjective pain reported by the patients showed a slightly greater improvement on the compressed lower leg compared with the non-compressed lower leg. None of the patients showed evidence of the Koebner phenomenon induced by compression therapy.

CONCLUSION

This is the first clinical study that systematically investigated the impact of compression therapy on psoriatic plaques. During the study period of 4 weeks, there was no significant improvement in psoriatic plaques; however, there was also no evidence of worsening of the skin condition. Thus, anti-edematous compression therapy can be performed in psoriasis patients without causing complications if basic contraindications are considered.

Therapeutic role of growth factors in treating diabetic wound

Wounds in diabetic patients, especially diabetic foot ulcers, are more difficult to heal compared with normal wounds and can easily deteriorate, leading to amputation. Common treatments cannot heal diabetic wounds or control their many complications. Growth factors are found to play important roles in regulating complex diabetic wound healing. Different growth factors such as transforming growth factor beta 1, insulin-like growth factor, and vascular endothelial growth factor play different roles in diabetic wound healing. This implies that a therapeutic modality modulating different growth factors to suit wound healing can significantly improve the treatment of diabetic wounds. Further, some current treatments have been shown to promote the healing of diabetic wounds by modulating specific growth factors. The purpose of this study was to discuss the role played by each growth factor in therapeutic approaches so as to stimulate further therapeutic thinking.

Hyperbaric Oxygen Therapy Reduces Oxidative Stress and Inflammation, and Increases Growth Factors Favouring the Healing Process of Diabetic Wounds

Hyperbaric oxygen therapy (HBOT) is the clinical application of oxygen at pressures higher than atmospheric pressure. HBOT has been effectively used to manage diverse clinical pathologies, such as non-healing diabetic ulcers. The aim of the present study was to analyse the effects of HBOT on the plasma oxidative and inflammation biomarkers and growth factors in patients with chronic diabetic wounds. The participants received 20 HBOT sessions (five sessions/week), and blood samples were obtained at sessions 1, 5 and 20, before and 2 h after the HBOT. An additional (control) blood sample was collected 28 days after wound recovery. No significant differences were evident in haematological parameters, whereas the biochemical parameters progressively decreased, which was significant for creatine phosphokinase (CPK) and aspartate aminotransferase (AST). The pro-inflammatory mediators, tumour necrosis factor alpha (TNF-α) and interleukin 1β (IL-1β), progressively decreased throughout the treatments. Biomarkers of oxidative stress--plasma protein levels of catalase, extracellular superoxide dismutase, myeloperoxidase, xanthine oxidase, malondialdehyde (MDA) levels and protein carbonyls--were reduced in accordance with wound healing. Plasma levels of growth factors--platelet-derived growth factor (PDFG), transforming growth factor β (TGF-β) and hypoxia-inducible factor 1-alpha (HIF-1α)-- were increased as a consequence of HBOT and reduced 28 days after complete wound healing, whereas matrix metallopeptidase 9 (MMP9) progressively decreased with the HBOT. In conclusion, HBOT reduced oxidative and pro-inflammatory mediators, and may participate in activating healing, angiogenesis and vascular tone regulation by increasing the release of growth factors.

Systematic review and meta-analysis of exercise therapy for venous leg ulcer healing and recurrence

OBJECTIVE

National guidelines in the United Kingdom have recommended regular exercise for individuals with venous leg ulceration. However, data on the effects of exercise on ulcer healing and recurrence are sparse. In the present study, we aimed to quantify the evidence for exercise regarding venous ulcer healing with respect to the primary outcomes of the proportion of healed ulcers and rate of ulcer recurrence. The secondary outcomes were improvement in ulcer symptoms, ulcer healing time, quality of life, compliance, and adverse events reported.

METHODS

The review followed PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines using a registered protocol (CRD42021220925). The MEDLINE and Embase databases and Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, European Union Clinical Trials, and International Standard Randomised Controlled Trial Number registries were searched up to April 6, 2022 and included studies comparing exercise therapy and compression vs compression alone. Data for the proportion of healed ulcers were pooled using a fixed effects meta-analysis.

RESULTS

After screening 1046 reports, 7 were included, with 121 participants allocated to exercise therapy and 125 to compression alone. All the reports were of randomized controlled trials and had reported ulcer healing at 12 weeks, with a pooled relative risk of ulcer healing of 1.38 for exercise vs compression (95% confidence interval, 1.11-1.71). Only one study had reported on recurrence; thus, data pooling was not performed. No differences between exercise and usual care were demonstrated. Compliance with exercise ranged from 33% to 81%. The included studies demonstrated low enrollment and a high risk of bias. Also, most of the trials had failed to demonstrate any differences in activity completed between the intervention and control arms.

CONCLUSIONS

A paucity of studies has examined leg ulcer recurrence after exercise programs, with no evidence to show that exercise is beneficial. Furthermore, the quality of evidence supporting exercise as an adjunct to ulcer healing is very low, and the trials demonstrated serious methodologic flaws, chiefly in recording the activity undertaken by the participants in the intervention arm. Future randomized controlled trials should implement activity monitoring and standardize the reporting of key patient, ulcer, and reflux characteristics to enable future meaningful meta-analyses to determine the role of exercise as an adjunct to venous leg ulceration healing.

Ageing decreases the healing of wounds in the skin of alcohol-preferring rats

OBJECTIVE

Alcohol consumption combined with ageing alters the healing process of the skin. We evaluated whether ageing decreases the healing of incisional wounds in the skin of Wistar rats of Universidade de Chile of variety B (UChB).

METHOD

A total of 20 adult rats and 20 older UChB rats, divided into two groups which underwent surgical aggression in the anterior region of the abdomen, were used: G1, adult rats (100 days old, control) with water and 10% ethanol; G2, aged rats (540 days old, experimental) with water and 10% ethanol; evaluated at 4, 7, 14 and 21 days after surgery.

RESULTS

Ageing did not alter the rupture force and collagen elasticity and resistance. There were increases in telomerase with the implementation of cellular senescence, in interleukin 1-alpha (IL-1α) at 14 days of healing, in epidermal growth factor (EGF) at 14 and 21 days of healing with delayed growth and development of keratinocytes, also an increase of IL-β at 4 days, and decrease in tumour necrosis factor (TNFα) at 7 days, associated with chronic scarring. There was an increase in vascular endothelial growth factor (VEGF) at 4 and 7 days, responsible for the early vessels re-establishment. There was a decrease in transforming growth factor 2-beta (TGFβ2) and β3 at 4 and 7 days of healing respectively, and estradiol at 4 days.

CONCLUSION

Ageing decreases the skin healing in incisional wounds in alcohol-preferring rats.

Transplantation of Wharton's jelly mesenchymal stem cells encapsulated with Hydroactive® Gel promotes diabetic wound antifibrotic healing in type 2 diabetic rats

Diabetic cutaneous ulcers (DCU) are a complication for diabetes patients, mostly occurring in the foot and causing non-healing diabetic foot ulcers. Mesenchymal stem cell (MSC)-based therapy is currently being investigated as a therapeutic avenue for chronic diabetic ulcers. However, poor engraftment, short retention, and low survival still limit the treatment effectiveness. Hydroactive® Gel is a sterile transparent gel made of natural hydrocolloid, which has been widely used for wound management. Whether transplantation of Wharton's jelly mesenchymal stem cells (WJMSCs) encapsulated with Hydroactive® Gel is helpful to diabetic ulcers wound healing remains to be explored. The biocompatibility experiments showed that WJMSCs embedded in Hydroactive® Gel did not influence the cell viability, survival, proliferation, and apoptosis of WJMSCs in vitro. RNA-seq results also implied that Hydroactive® Gel + WJMSCs transplantation activated the "cytokine-cytokine receptor interaction", "mononuclear cell differentiation", "regulation of cell-cell adhesion", and "chemokine receptor activity" to accelerate the inflammatory reaction and epidermis regeneration in diabetic wounds. Histological analysis results demonstrated that Hydroactive® Gel encapsulated WJMSCs transplantation promoted diabetic wound healing and regeneration, indicating improved dermis regeneration, sebaceous gland formation, and type III collagen fiber deposition. Besides, immunohistochemical analysis results showed that Hydroactive® Gel + WJMSCs transplantation also facilitated the transformation of pro-inflammatory M1 macrophages to anti-inflammatory M2 macrophages, cell proliferation, and neovascularization at the wound site. Hydroactive® Gel encapsulation further prolonged the retention time of WJMSCs at the diabetic wound site. Above all, Hydroactive® Gel accelerates WJMSCs-mediated diabetic wound healing by promoting macrophage transformation, facilitating cell proliferation and angiogenesis, and prolonging cell retention time. Our findings may potentially provide a useful therapeutic strategy based on the combination of WJMSCs and biomedical materials for patients with diabetic cutaneous ulcers.

Homocysteine and Inflammatory Cytokines in the Clinical Assessment of Infection in Venous Leg Ulcers

Inflammation and biofilm-associated infection are common in chronic venous leg ulcers (VU), causing deep pain and delayed healing. Albeit important, clinical markers and laboratory parameters for identifying and monitoring persistent VU infections are limited. This study analyzed 101 patients with infected (IVU) and noninfected VUs (NVU). Clinical data were collected in both groups. The serum homocysteine (Hcys) and inflammatory cytokines from the wound fluid were measured. In addition, microbial identification, antibiotic susceptibility, and biofilm production were examined. IVU were 56 (55.4%) while NVU were 45 (44.5%). IVUs showed a significant increase in the wound's size and depth compared to NVUs. In addition, significantly higher levels of interleukin (IL)-6, IL-10, IL17A, and tumor necrosis factor-alpha (TNF-α) were found in patients with IVUs compared to those with NVUs. Notably, hyperhomocysteinemia (HHcy) was significantly more common in patients with IVUs than NVUs. A total of 89 different pathogens were identified from 56 IVUs. Gram-negative bacteria were 51.7%, while the Gram-positives were 48.3%. At the species level, Staphylococcus aureus was the most common isolate (43.8%), followed by Pseudomonas aeruginosa (18.0%). Multidrug-resistant organisms (MDROs) accounted for 25.8% of the total isolates. Strong biofilm producers (SBPs) (70.8%) were significantly more abundant than weak biofilm producers (WBP) (29.2%) in IVUs. SBPs were present in 97.7% of the IVUs as single or multispecies infections. Specifically, SBPs were 94.9% for S. aureus, 87.5% for P. aeruginosa, and 28.6% for Escherichia coli. In IVU, the tissue microenvironment and biofilm production can support chronic microbial persistence and a most severe clinical outcome even in the presence of an intense immune response, as shown by the high levels of inflammatory molecules. The measurement of local cytokines in combination with systemic homocysteine may offer a novel set of biomarkers for the clinical assessment of IVUs caused by biofilm-producing bacteria.

Involvement of Inflammation and Its Resolution in Disease and Therapeutics

Inflammation plays a critical role in the response to and survival from injuries and/or infections. It occurs in two phases: initiation and resolution; however, when these events do not resolve and persist over time, the inflammatory response becomes chronic, prompting diseases that affect several systems and organs, such as the vasculature and the skin. Here, we reviewed inflammation that occurs in selected infectious and sterile pathologies. Thus, the immune processes induced by bacterial sepsis as well as T. cruzi and SARS-CoV-2 infections are shown. In addition, vaccine adjuvants as well as atherosclerosis are revised as examples of sterile-mediated inflammation. An example of the consequences of a lack of inflammation resolution is given through the revision of wound healing and chronic wounds. Then, we revised the resolution of the latter through advanced therapies represented by cell therapy and tissue engineering approaches, showing how they contribute to control chronic inflammation and therefore wound healing. Finally, new pharmacological insights into the management of chronic inflammation addressing the resolution of inflammation based on pro-resolving mediators, such as lipoxin, maresin, and resolvins, examining their biosynthesis, biological properties, and pharmacokinetic and pharmaceuticals limitations, are given. We conclude that resolution pharmacology and advanced therapies are promising tools to restore the inflammation homeostasis.

Fibroblast-like cells Promote Wound Healing via PD-L1-mediated Inflammation Resolution

Chronic non-healing wounds fail to progress beyond the inflammatory phase, characterized by a disorder of inflammation resolution. PD-1/PD-L1, a major co-inhibitory checkpoint signaling, plays critical roles in tumor immune surveillance and the occurrence of inflammatory or autoimmune diseases, but its roles in wound healing remains unclear. Here, we described a novel function of PD-L1 in fibroblast-like cells as a positive regulator of wound healing. PD-L1 dynamically expressed on the fibroblast-like cells in the granulation tissue during wound healing to form a wound immunosuppressive microenvironment, modulate macrophages polarization from M1-type to M2-type, and initiates resolution of inflammation, finally accelerate wound healing. Loss of PD-L1 delayed wound healing, especially in mice with LPS-induced severe inflammation. Furthermore, the mainly regulatory mechanism is that combination of FGF-2 and TGF-β1 promotes PD-L1 translation in fibroblasts through enhancing the eIF4E availability regulated by both PI3K-AKT-mTOR-4EBP1 and p38-ERK-MNK signaling pathways. Our results reveal the positive role of PD-L1 in wound healing, and provide a new strategy for the treatment of chronic wounds.

[Granulomatous dermatoses]

The group of granulomatous dermatoses refers to a multitude of clinically different diseases, which are characterized by a histopathologically similar pattern of inflammation. The cause of granulomatous inflammatory reactions can be infections and also noninfectious stimuli, such as cell disintegration or foreign bodies. The aim of this immunological defence reaction is encapsulation in order to prevent further spread and delimitation from healthy tissue. This is histologically expressed as a granuloma in the sense of a circumscribed aggregation of histiocytes and multinucleated giant cells mostly in dermal connective tissue. The following can be histologically differentiated: sarcoid granuloma characterized by a sparse lymphocytic inflammatory infiltrate and tuberculous granuloma with central necrosis and denser lymphocytic inflammatory infiltrate. Neutrophilic granulocytes together with macrophages occur in suppurative granulomas and palisaded granulomas are characterized by peripherally arrayed macrophages.

Cytokines and Venous Leg Ulcer Healing-A Systematic Review

Venous leg ulcers (VLUs) are the most common type of leg ulcers with a significant socioeconomic burden due to slow healing. Cytokines may be involved in the pathogenesis of VLUs. In this systematic review, our objective was to investigate the association between cytokine levels, including growth factors, with the healing of VLUs. PubMed, Embase, Web of Science and Cochrane Library were searched from their inception to August 2021. We retrieved 28 articles investigating 38 different cytokines in 790 patients. Cytokines were most commonly investigated in wound fluid and less frequently in biopsies and serum. The studies were judged as having a moderate to high risk of bias, and the results were often inconsistent and sometimes conflicting. A meta-analysis was not performed due to clinical and methodological heterogeneities. We found weak evidence for elevated IL-1α, IL-6, IL-8, TNF-α and VEGF levels in non-healing VLUs, an elevation that declined with healing. TGF-β1 levels tended to increase with VLU healing. Other cytokines warranting further investigations include EGF, FGF-2, GM-CSF, IL-1β, IL-1Ra and PDGF-AA/PDGF-BB. We conclude that non-healing VLUs may be associated with an elevation of a palette of pro-inflammatory cytokines, possibly reflecting activated innate immunity in these wounds. There is a paucity of reliable longitudinal studies monitoring the dynamic changes in cytokine levels during wound healing.

Ozone improved the wound healing in type 2 diabetics via down-regulation of IL- 8, 10 and induction of FGFR expression

Background and aim:

We aimed to investigate the effect of ozonated autohaemotherapy (OA) on the wound healing, serum values of interleukin (IL) - 6, 8, 10, tumor necrosis factor-alpha (TNF-α), basic fibroblast growth factor (bFGF) and local expression of fibroblast growth factor receptors (FGFR) in type 2 diabetics with the acute soft-tissue infections.

Methods:

Patients in the first cohort (n-30) received a basic comprehensive treatment (BCT-group), and the second (n=28) also received OA (OA-group). Blood samples for ELISA and tissue specimens for the immunohistochemical examinations were collected at admission (day 0) and at the 9th day of inpatient treatment.

Results:

The additional using of OA has accelerated the timing of a single and the complete wound granulation and the timing to marginal epithelization, compared with the results of the standard treatment. The use of OA has significantly reduced the production of IL-8, 10 at 9th day. OA-group patients were characterized by consistently high levels of bFGF production in contrast to the BCT-group, where the decreasing in the serum bFGF level was observed. The maximum number of bFGFR - immunopositive labels was observed in OA-group out to 9th day (319,45 (249,90-348,43) versus baseline 192,65 (171,93-207,72), versus BCT-group 123,30 (105,23- 141,10), p<0,001).

Conclusions:

Application of OA in the complex treatment of the acute soft-tissue infections in diabetics makes it possible to achieve the significant reductions in the duration of the wound inflammation and regeneration phases by eliminating of overproduction of IL- 8, 10 and induction of expression of bFGF and its receptors. (www.actabiomedica.it)

Effects of systemic androgens on late-stage urethral wound healing: An animal study

BACKGROUND

There are limited data regarding the effects of systemic androgens on late-stage urethral wound healing.

OBJECTIVE

To evaluate the effects of systemic androgens on fibrosis and scar formation in late-stage urethral wound healing.

MATERIALS AND METHODS

Forty-five male Sprague Dawley rats were divided into three groups. First group consisted of 15 rats that were castrated on 23 days of age and were given 5 mg/kg testosterone undecanoate with 1/25 ml cottonseed oil intraperitoneally at weekly intervals for 3 weeks (castrated and replaced with testosterone rats [CAS+T] group). The castrated rats (CAS) group included 15 castrated rats. The remaining 15 rats underwent sham surgery. CAS and sham groups also received 1/25 ml cottonseed oil intraperitoneally at weekly intervals for 3 weeks. Furthermore, all groups were divided into three subgroups after testosterone/placebo administration (urethroplasty performed after first, second, and third weeks) in accordance with the urethroplasty timing. All animals were sacrificed 6 weeks after urethroplasty. Serum testosterone level was measured, tissue samples were investigated using hematoxylin and eosin and Masson's trichrome. Alpha-SMA, Coll 1 and Coll 3 primary antibodies were applied for immunohistochemical examination. Expression of cytokines and growth factors, such as Bax, Bcl2, IL-10, IP-10, TNF-alpha, TGFb1, MMP9, Col-I, Col-III, TIMP-1, fibronectin, fibroblast growth factor 10, platelet-derived growth factor, alpha-SMA, were also evaluated in the tissues.

RESULTS

The blood testosterone levels were significantly higher in CAS+T group at the time of urethroplasty compared with the levels in CAS group; however, this difference was not observed at the time of sacrification (p < 0.001 and 0.97, respectively). Histological analysis with hematoxylin and eosin and Masson's trichrome staining revealed a significantly higher fibrosis in the sham group compared with the others. Significantly lower fibrosis was detected in the CAS group in the pairwise comparison of the pathological fibrosis area between the CAS and CAS+T groups (p < 0.001). Furthermore, tissue collagen-1, collagen-3, and alpha-SMA expression levels were statistically different between CAS and CAS+T groups (p < 0.001, <0.05, and <0.001, respectively). The tissue levels of BAX, TIM-1, MMP-9, Coll-I, Coll-III, TGF-beta, TNF-alpha, and IL-10 mRNA expressions in the CAS+T group were different than the levels in CAS group (as <0.5-fold and >1.5-fold changes, respectively). The expressions of all these markers were significantly higher in the sham group. The subgroup analysis of CAS+T group (urethroplasty performed after first, second, and third weeks) revealed similar histopathological wound healing findings.

DISCUSSION

Debate continues on the effects and benefits of androgen use regarding urethral healing. There are two main routes for administration as systemic or local. This study focuses on the late-stage histologic and biochemical effects of systemic androgens.

CONCLUSION

Systemic androgens adversely affect wound healing and cause abnormal extracellular matrix as well as scar formation.

Features of cellular and molecular mechanisms of re-gulation of reparative processes in chronic wounds using photobiomodulation therapy

Introduction: Treatment of chronic wounds is an urgent worldwide problem for medicine. Among the many efforts in wound healing techniques, photobiomodulation therapy has shown promising results.

Aim: To study the effect of photobiomodulation therapy on optimisation of the regulation of reparative processes in chronic wounds by cytokines (through the example of interleukin-1β, tumour necrosis factor-alpha, interleukin-6, interleukin-4, interleukin-10, and granulocyte macrophage colony stimulating factor).

Materials and methods: The study involved 12 Wistar rats. A trophic wound was modelled in the animals. After the operation, the animals were divided into two groups of 6 animals each. The wound defects of animals in the experimental group were exposed to low-intensity laser radiation. Photobiomodulation therapy was applied once a day for 5 days, starting the day after wound modelling. The device Lika-therapist M (Ukraine) was used in a continuous mode at a wavelength of 660 nm, an output power of 50 mW, and an energy density of 1 J/cm², and 60 s exposure time.

Results: The study showed the following changes in the expression of intercellular mediators in the blood serum of animals with chronic wounds when using photobiomodulation therapy: a decrease in the levels of interleukin-1β (p&gt;0.05) and tumour necrosis factor-alpha (p&lt;0.05); increased concentrations of interleukin-4 (p&lt;0.05); the concentrations of interleukin-6, granulocyte macrophage colony stimulating factor, and interleukin-10 were not significantly changed. The histological study showed better organization of collagen fibers in the experimental group.

Conclusions: Photobiomodulation therapy can be an instrument for optimizing the reparative process by correcting the regulation by intercellular mediators.

MDL-800, the SIRT6 Activator, Suppresses Inflammation via the NF-κB Pathway and Promotes Angiogenesis to Accelerate Cutaneous Wound Healing in Mice

Sirtuin 6 (SIRT6) is an NAD+-dependent deacetylase belonging to the sirtuin family. It has been shown to participate in wound healing and some inflammation-related disorders. However, the effect of MDL-800, a highly efficient and selective SIRT6 activator, on wound healing and inflammation has not been reported. Therefore, this study investigated whether MDL-800 confers anti-inflammatory effects and promotes wound healing and uncovered the molecular mechanisms involved. This was achieved using mouse models of full-thickness wounds. Results showed that MDL-800 significantly downregulated inflammation by attenuating the release of inflammatory mediators and improved collagen deposition and neovascularization of wounds, thereby accelerating cutaneous wound healing. Furthermore, MDL-800 significantly downregulated expression levels of TNF-α and IL-6 in the dorsal skin tissue of mice via the NF-κB pathway. These results demonstrated that MDL-800 exerted anti-inflammatory and prohealing effects, indicating that the SIRT6/NF-κB/IκB signaling pathway may play an important role in wound healing.

Compression Garments for Recovery from Muscle Damage: Evidence and Implications of Dose Responses

ABSTRACT

The use of compression garments (CG) has been associated with improved recovery following exercise-induced muscle damage. The mechanisms responsible are not well established, and no consensus exists regarding the effects of compression pressure (i.e., the "dose"), which until recently was seldom reported. With the increasing prevalence of studies reporting directly measured pressures, the present review aims to consolidate current evidence on optimal pressures for recovery from exercise-induced muscle damage. In addition, recent findings suggesting that custom-fitted garments provide greater precision and experimental control are discussed. Finally, biochemical data from human trials are presented to support a theoretical mechanism by which CG enhance recovery, with recommendations for future research. The effects of compression on adaptation remain unexplored. More studies are required to investigate the relationship between compression pressure and the recovery of performance and physiological outcomes. Furthermore, improved mechanistic understanding may help elucidate the optimal conditions by which CG enhance recovery.

Acceleration of chronic wound healing by bio-inorganic polyphosphate: In vitro studies and first clinical applications

The healing of chronic wounds is impaired by a lack of metabolic energy. In previous studies, we showed that physiological inorganic polyphosphate (polyP) is a generator of metabolic energy by forming ATP as a result of the enzymatic cleavage of the high-energy phosphoanhydride bonds of this polymer. Therefore, in the present study, we investigated whether the administration of polyP can substitute for the energy deficiency in chronic wound healing.

Methods: PolyP was incorporated into collagen mats and applied in vitro and to patients in vivo.

Results: (i) In vitro studies: Keratinocytes grown in vitro onto the polyP/collagen mats formed long microvilli to guide them to a favorable environment. HUVEC cells responded to polyP/collagen mats with an increased adhesion and migration propensity as well as penetration into the mats. (ii) In vivo - human clinical studies: In a “bench to bedside” process these promising in vitro results were translated from the laboratory into the clinic. In the proof-of-concept application, the engineered polyP/collagen mats were applied to chronic wounds in patients. Those mats impressively accelerated the re-epithelialization rate, with a reduction of the wound area to 65% after 3 weeks and to 36.6% and 22.5% after 6 and 9 weeks, respectively. Complete healing was achieved and no further treatment was necessary. Biopsy samples from the regenerating wound area showed predominantly myofibroblasts. The wound healing process was supported by the use of a polyP containing moisturizing solution.

Conclusion: The results strongly recommend polyP as a beneficial component in mats for a substantial healing of chronic wounds.

Polyphosphate in Chronic Wound Healing: Restoration of Impaired Metabolic Energy State

Many pathological conditions are characterized by a deficiency of metabolic energy. A prominent example is nonhealing or difficult-to-heal chronic wounds. Because of their unique ability to serve as a source of metabolic energy, inorganic polyphosphates (polyP) offer the opportunity to develop novel strategies to treat such wounds. The basis is the generation of ATP from the polymer through the joint action of two extracellular or plasma membrane-bound enzymes alkaline phosphatase and adenylate kinase, which enable the transfer of energy-rich phosphate from polyP to AMP with the formation of ADP and finally ATP. Building on these findings, it was possible to develop novel regeneratively active materials for wound therapy, which have already been successfully evaluated in first studies on patients.

Polylysine for skin regeneration: A review of recent advances and future perspectives

There have been several attempts to find promising biomaterials for skin regeneration, among which polylysine (a homopolypeptide) has shown benefits in the regeneration and treatment of skin disorders. This class of biomaterials has shown exceptional abilities due to their macromolecular structure. Polylysine-based biomaterials can be used as tissue engineering scaffolds for skin regeneration, and as drug carriers or even gene delivery vectors for the treatment of skin diseases. In addition, polylysine can play a preservative role in extending the lifetime of skin tissue by minimizing the appearance of photodamaged skin. Research on polylysine is growing today, opening new scenarios that expand the potential of these biomaterials from traditional treatments to a new era of tissue regeneration. This review aims to address the basic concepts, recent trends, and prospects of polylysine-based biomaterials for skin regeneration. Undoubtedly, this class of biomaterials needs further evaluations and explorations, and many critical questions have yet to be answered.

Resveratrol-Induced Signal Transduction in Wound Healing

Resveratrol is a well-known polyphenol that harbors various health benefits. Besides its well-known anti-oxidative potential, resveratrol exerts anti-inflammatory, pro-angiogenic, and cell-protective effects. It seems to be a promising adjuvant for various medical indications, such as cancer, vascular, and neurodegenerative diseases. Additionally, resveratrol was shown to display beneficial effects on the human skin. The polyphenol is discussed to be a feasible treatment approach to accelerate wound healing and prevent the development of chronic wounds without the drawback of systemic side effects. Despite resveratrol’s increasing popularity, its molecular mechanisms of action are still poorly understood. To take full advantage of resveratrol’s therapeutic potential, a profound knowledge of its interactions with its targets is needed. Therefore, this review highlights the resveratrol-induced molecular pathways with particular focus on the most relevant variables in wound healing, namely inflammation, oxidative stress, autophagy, collagen proliferation and angiogenesis.

Harnessing Multifaceted Next-Generation Technologies for Improved Skin Wound Healing

Dysregulation of sequential and synchronized events of skin regeneration often results in the impairment of chronic wounds. Conventional wound dressings fail to trigger the normal healing mechanism owing to the pathophysiological conditions. Tissue engineering approaches that deal with the fabrication of dressings using various biomaterials, growth factors, and stem cells have shown accelerated healing outcomes. However, most of these technologies are associated with difficulties in scalability and cost-effectiveness of the products. In this review, we survey the latest developments in wound healing strategies that have recently emerged through the multidisciplinary approaches of bioengineering, nanotechnology, 3D bioprinting, and similar cutting-edge technologies to overcome the limitations of conventional therapies. We also focus on the potential of wearable technology that supports complete monitoring of the changes occurring in the wound microenvironment. In addition, we review the role of advanced devices that can precisely enable the delivery of nanotherapeutics, oligonucleotides, and external stimuli in a controlled manner. These technological advancements offer the opportunity to actively influence the regeneration process to benefit the treatment regime further. Finally, the clinical relevance, trajectory, and prospects of this field have been discussed in brief that highlights their potential in providing a beneficial wound care solution at an affordable cost.

A service evaluation to examine the use of compression strapping for the management of patients with retromalleolar leg ulcers in a specialist community setting

Leg ulcers are costly to the NHS, and they have a significant impact on patients' physical, social, and psychological well-being. Compression therapy is traditionally the "gold-standard" treatment for the management of venous leg ulcers and can be beneficial for those individuals with mixed ulcer aetiology. Evidence suggests that the application of standard, strong, graduated compression bandaging does not apply therapeutic compression to the retromalleolar fossa. The addition of compression strapping has been found to increase sub-bandage pressure, promote healing, reduce pain and increase quality of life in patients with retromalleolar leg ulcers. This service evaluation aimed at evaluating the use of compression strapping with patients with retromalleolar leg ulcers. The service evaluation included 24 patients with 41 ulcers treated with compression strapping by a specialist team. Patients treated with CS had multiple comorbidities and shared common characteristics including foot and ankle oedema, previous ulceration, reduced mobility, and failure to heal despite the application of "gold-standard" compression therapy. Following application of compression strapping, 17 patients (n = 27/41 ulcers) healed, mean pain scores decreased, and mean quality of life scores increased. The compression strapping was tolerated well, and patients reported a positive experience. This service evaluation has contributed towards a growing evidence base that supports the use of CS for the management of patients with retromalleolar leg ulcers.

Preparation of W/O Hypaphorine-Chitosan Nanoparticles and Its Application on Promoting Chronic Wound Healing via Alleviating Inflammation Block

Chronic wound repair is a common complication in patients with diabetes mellitus, which causes a heavy burden on social medical resources and the economy. Hypaphorine (HYP) has good anti-inflammatory effect, and chitosan (CS) is used in the treatment of wounds because of its good antibacterial effect. The purpose of this research was to investigate the role and mechanism of HYP-nano-microspheres in the treatment of wounds for diabetic rats. The morphology of HYP-NPS was observed by transmission electron microscopy (TEM). RAW 264.7 macrophages were used to assess the bio-compatibility of HYP-NPS. A full-thickness dermal wound in a diabetic rat model was performed to evaluate the wound healing function of HYP-NPS. The results revealed that HYP-NPS nanoparticles were spherical with an average diameter of approximately 50 nm. The cell experiments hinted that HYP-NPS had the potential as a trauma material. The wound test in diabetic rats indicated that HYP-NPS fostered the healing of chronic wounds. The mechanism was through down-regulating the expression of pro-inflammatory cytokines IL-1β and TNF-α in the skin of the wound, and accelerating the transition of chronic wound from inflammation to tissue regeneration. These results indicate that HYP-NPS has a good application prospect in the treatment of chronic wounds.

Gout-associated uric acid crystals induce tophi ulcerations and impair wound healing in a novel gouty ulcer model

This study aimed to establish a novel gouty ulcer rat model induced by monosodium urate (MSU) deposition and preliminarily explored how MSU crystals affected wound healing. MSU crystals were subcutaneously injected into the back of rats to simulate tophi formation and ulceration. Ultrasound was used to detect the formation of gouty tophi. MSU crystal deposition and histopathological changes were analysed by haematoxylin-eosin staining. After the skin over the tophi became broken in the model group, a full-thickness tissue defect of the same area was made on the backs of the phosphate buffered saline (PBS) controls. On Days 3, 7, and 14 after wounding, the infiltration of neutrophils and macrophages and the expression of inflammatory markers, including interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α), and Nod-like receptor protein 3 (NLRP3), were examined by immunohistochemical staining and Western blotting, respectively. After the first subcutaneous injection in rats, local tissues showed redness and swelling, indicating inflammation on approximately Day 14. Tophi-like manifestations appeared on approximately Day 18. Tophi appeared heterogeneously hyperechoic by ultrasound. Swelling and redness in injured tissue areas increased on approximately Day 22, skin tissue necrosis was seen in a small area on approximately Day 26, and skin necrosis was enlarged and the tophi were ulcerated on approximately Day 32, accompanied by yellowish-white, chalky secretions. Haematoxylin and eosin staining showed dermal deposition of needle-like crystals with surrounding granulomatous inflammation. On Days 3, 7, and 14 after wounding, immunohistochemical staining showed the infiltration of neutrophils and macrophages, and the expression of inflammation-related proteins (IL-1β, TNF-α, and NLRP3) were upregulated in gouty ulcers compared with those of PBS controls. The gouty ulcers were not completely healed by Day 14 compared with those in the PBS controls. In this study, a novel gouty ulcer rat model was constructed, which also revealed the existence of persistent chronic inflammation.

Diabetic Wound-Healing Science

Diabetes mellitus is an increasingly prevalent chronic metabolic disease characterized by prolonged hyperglycemia that leads to long-term health consequences. It is estimated that impaired healing of diabetic wounds affects approximately 25% of all patients with diabetes mellitus, often resulting in lower limb amputation, with subsequent high economic and psychosocial costs. The hyperglycemic environment promotes the formation of biofilms and makes diabetic wounds difficult to treat. In this review, we present updates regarding recent advances in our understanding of the pathophysiology of diabetic wounds focusing on impaired angiogenesis, neuropathy, sub-optimal chronic inflammatory response, barrier disruption, and subsequent polymicrobial infection, followed by current and future treatment strategies designed to tackle the various pathologies associated with diabetic wounds. Given the alarming increase in the prevalence of diabetes, and subsequently diabetic wounds, it is imperative that future treatment strategies target multiple causes of impaired healing in diabetic wounds.

Oral wound healing models and emerging regenerative therapies

Following injury, the oral mucosa undergoes complex sequences of biological healing processes to restore homeostasis. While general similarities exist, there are marked differences in the genomics and kinetics of wound healing between the oral cavity and cutaneous epithelium. The lack of successful therapy for oral mucosal wounds has influenced clinicians to explore alternative treatments and potential autotherapies to enhance intraoral healing. The present in-depth review discusses current gold standards for oral mucosal wound healing and compares endogenous factors that dictate the quality of tissue remodeling. We conducted a review of the literature on in vivo oral wound healing models and emerging regenerative therapies published during the past twenty years. Studies were evaluated by injury models, therapy interventions, and outcome measures. The success of therapeutic approaches was assessed, and research outcomes were compared based on current hallmarks of oral wound healing. By leveraging therapeutic advancements, particularly within in cell-based biomaterials and immunoregulation, there is great potential for translational therapy in oral tissue regeneration.

Biofilm and Equine Limb Wounds

Simple Summary

Delayed wound healing commonly occurs in limb wounds of horses. These equine limb wounds share many similarities with chronic wounds in humans and one of them seems to be the presence of biofilm, even though equine wound biofilm research is just emerging. Biofilms are aggregates of bacteria, and within these aggregates, the bacteria are protected from both antimicrobial substances and the immune response of the host. Biofilm infections in wounds often delay healing and are impossible to detect with routine diagnostics. However, if suspected, aggressive treatment is needed and includes physically removing biofilm and unhealthy tissue from the wound during debridement and immediately applying antimicrobial compounds to kill any biofilm or bacteria not removed during debridement.

Abstract

In chronic wounds in humans, biofilm formation and wound chronicity are linked, as biofilms contribute to chronic inflammation and delayed healing. Biofilms are aggregates of bacteria, and living as biofilms is the default mode of bacterial life; within these aggregates, the bacteria are protected from both antimicrobial substances and the immune response of the host. In horses, delayed healing is more commonly seen in limb wounds than body wounds. Chronic inflammation and hypoxia are the main characteristics of delayed wound healing in equine limbs, and biofilms might also contribute to this healing pattern in horses. However, biofilm formation in equine wounds has been studied to a very limited degree. Biofilms have been detected in equine traumatic wounds, and recent experimental models have shown that biofilms protract the healing of equine limb wounds. Detection of biofilms within wounds necessitates advanced techniques that are not available in routine diagnostic yet. However, infections with biofilm should be suspected in equine limb wounds not healing as expected, as they are in human wounds. Treatment should be based on repeated debridement and application of topical antimicrobial therapy.

Chemokine-Capturing Wound Contact Layer Rescues Dermal Healing

Excessive inflammation often impedes the healing of chronic wounds. Scavenging of chemokines by multiarmed poly(ethylene glycol)-glycosaminoglycan (starPEG-GAG) hydrogels has recently been shown to support regeneration in a diabetic mouse chronic skin wound model. Herein, a textile-starPEG-GAG composite wound contact layer (WCL) capable of selectively sequestering pro-inflammatory chemokines is reported. Systematic variation of the local and integral charge densities of the starPEG-GAG hydrogel component allows for tailoring its affinity profile for biomolecular signals of the wound milieu. The composite WCL is subsequently tested in a large animal (porcine) model of human wound healing disorders. Dampening excessive inflammatory signals without affecting the levels of pro-regenerative growth factors, the starPEG-GAG hydrogel-based WCL treatment induced healing with increased granulation tissue formation, angiogenesis, and deposition of connective tissue (collagen fibers). Thus, this biomaterials technology expands the scope of a new anti-inflammatory therapy toward clinical use.

Wounds in chronic leg oedema

Wounds and chronic oedema are common disorders, but rarely studied together. The objective of this cross-sectional study was to investigate the point-prevalence and risk factors of wounds on the leg, in chronic leg oedema. Forty sites in nine countries were included. Of 7077 patients with chronic leg oedema, 12.70% had wounds. Independent risk factors were: peripheral arterial disease (odds ratio (OR) 4.87, 95% confidence intervals (CI) 3.63-6.52), cellulitis within the past 12 months (OR 2.69, 95% CI 2.25-3.21), secondary lymphoedema (OR 2.64, 95% CI 1.93-3.60), being male (OR 2.08, 95% CI 1.78-2.44), being over 85 years of age (OR 1.80, 95% CI 1.23-2.62), underweight (OR 1.79, 95% CI 1.14-2.79), bed bound (OR 1.79, 95% CI 1.01-3.16), chair bound (OR 1.52, 95% CI 1.18-1.97), diabetes (OR 1.47, 95% CI 1.23-1.77), and walking with aid (OR 1·41, 95% CI 1.17-1.69). 43.22% of those with wounds had clinically defined well-controlled oedema, associated with a significantly lower risk of wounds (OR 0.50, 95% CI 0.42-0.58, P < .001). Hard/fibrotic tissue (OR 1.71, 95% CI 1.19-2.48), and a positive Stemmers sign (OR 1.57, 95% CI 1.05-2.35) were associated with wounds. The study reinforces the importance of measures to control oedema, as controlled swelling was associated with a 50% lower risk of wounds.

Tissue remodelling and increased DNA damage in patients with incompetent valves in chronic venous insufficiency

Chronic venous insufficiency (CVI), in which blood return to the heart is impaired, is a prevalent condition worldwide. Valve incompetence is a complication of CVI that results in blood reflux, thereby aggravating venous hypertension. While CVI has a complex course and is known to produce alterations in the vein wall, the underlying pathological mechanisms remain unclear. This study examined the presence of DNA damage, pro‐inflammatory cytokines and extracellular matrix remodelling in CVI‐related valve incompetence. One hundred and ten patients with CVI were reviewed and divided into four groups according to age (<50 and ≥50 years) and a clinical diagnosis of venous reflux indicating venous system valve incompetence (R) (n = 81) or no reflux (NR) (n = 29). In vein specimens (greater saphenous vein) from each group, PARP, IL‐17, COL‐I, COL‐III, MMP‐2 and TIMP‐2 expression levels were determined by RT‐qPCR and immunohistochemistry. The younger patients with valve incompetence showed significantly higher PARP, IL‐17, COL‐I, COL‐III, MMP‐2 and reduced TIMP‐2 expression levels and a higher COL‐I/III ratio. Young CVI patients with venous reflux suffer chronic DNA damage, with consequences at both the local tissue and systemic levels, possibly associated with ageing.

Evaluation and Management of Patients with Leg Swelling: Therapeutic Options for Venous Disease and Lymphedema

Lower extremity swelling is a common condition which has a variety of etiologies and can be challenging to diagnose and manage. Swelling is usually the result of the accumulation of interstitial fluid in the subcutaneous tissues. Common etiologies include systemic, superficial, and deep venous, and lymphatic disorders. Leg swelling can occur bilaterally or unilaterally, with venous disorders being one of the most common causes of unilateral lower extremity edema.

Wound Repair and Extremely Low Frequency-Electromagnetic Field: Insight from In Vitro Study and Potential Clinical Application

Wound healing is a complex, staged process. It involves extensive communication between the different cellular constituents of various compartments of the skin and its extracellular matrix (ECM). Different signaling pathways are determined by a mutual influence on each other, resulting in a dynamic and complex crosstalk. It consists of various dynamic processes including a series of overlapping phases: hemostasis, inflammation response, new tissue formation, and tissue remodeling. Interruption or deregulation of one or more of these phases may lead to non-healing (chronic) wounds. The most important factor among local and systemic exogenous factors leading to a chronic wound is infection with a biofilm presence. In the last few years, an increasing number of reports have evaluated the effects of extremely low frequency (ELF) electromagnetic fields (EMFs) on tissue repair. Each experimental result comes from a single element of this complex process. An interaction between ELF-EMFs and healing has shown to effectively modulate inflammation, protease matrix rearrangement, neo-angiogenesis, senescence, stem-cell proliferation, and epithelialization. These effects are strictly related to the time of exposure, waveform, frequency, and amplitude. In this review, we focus on the effect of ELF-EMFs on different wound healing phases.

The effect of custom-fitted compression garments worn overnight for recovery from judo training in elite athletes

This study investigated the effects of custom-fitted compression garments (CG) worn during recovery over a multi-day training camp in elite judo players (judoka). A single blind, placebo-controlled study was carried out in 11 elite judoka, using a two-way crossover design. Two three-day training camps were completed in CG and placebo conditions in a random order. Changes in performance and physiological markers were compared between conditions. Judoka were assessed before training for (maximal) isometric knee extension and grip strength, countermovement jump performance and bench-press velocity, alongside soreness, limb circumferences, plasma creatine kinase activity (CK) and perceived bruising. Measurements were repeated after 12, 36 and 43 h of training, whereupon judoka rated the effectiveness of each intervention. Knee extension and bench-press performance demonstrated significant familiarization (p < 0.001), and were excluded from subsequent analysis. Jump performance was unaffected by training (p > 0.05). Grip strength declined throughout training (p < 0.001), with peak decrements of -9.7% indicating mild muscle damage. Increases in bruising, CK and soreness demonstrated highly variable, if significant (p < 0.001) responses. Although CG were perceived as significantly more effective than placebo for recovery (p = 0.046), no effects were observed for any other outcome (p > 0.05). Compression conferred no statistically significant impact upon recovery markers in elite judoka throughout training. Muscle damage responses were inconsistent in this population. Individual athletes would be advised to monitor habitually-used performance measures while using CG to ascertain whether perceptual benefits translate into enhanced recovery. HighlightsCompression garments were perceived as more effective for recovery than placebo by elite judoka.However, no measures of performance or muscle damage were enhanced by CG.Randori was associated with inconsistent muscle damage responses in elite judoka, while lower-body performance was not impaired.Individual athletes would be advised to monitor habitually-used performance measures while using CG to ascertain whether perceptual benefits translate into enhanced recovery.

Case Report: Rehabilitation for Lower Extremity Pain Due to Venous Stasis in a Patient With Multisystem Inflammatory Syndrome in Children

Recently, it was reported that children recovering from coronavirus disease (COVID-19) developed multisystem inflammatory syndrome in children (MIS-C), which causes severe inflammation in multiple organs of the body. Because MIS-C is a new disease, the pathophysiology and prognosis are unknown. Owing to a lack of studies on this subject, we herein provide information on rehabilitation for children with MIS-C. A 12-year-old male patient presented with systemic inflammatory symptoms after approximately 2 months since recovery from COVID-19. He was treated with cyclosporine and steroid pulse therapy after admission to our hospital. His general condition improved significantly within approximately 1 week. Thereafter, his lower legs turned dark purple and he experienced intense pain whenever the lower limbs hung below the heart, such as in the sitting position. The patient was referred to the rehabilitation department, as he had difficulties during standing and walking. Because the symptoms improved with elevation of the lower extremities, we considered that the pain was related to venous stasis. The pain reduced when an elastic bandage was applied for the prevention of venous stasis; therefore, exercise therapy was implemented while the patient wore the elastic bandage. The patient's lower extremity symptoms improved in 10 days. He was discharged after 16 days and could independently perform activities of daily living (ADL). The mechanism underlying the patient's pain could not be determined; however, rehabilitation was effective when combined with compression therapy using an elastic bandage.

Why Venous Leg Ulcers Have Difficulty Healing: Overview on Pathophysiology, Clinical Consequences, and Treatment

Venous leg ulcers (VLUs) are one of the most common ulcers of the lower extremity. VLU affects many individuals worldwide, could pose a significant socioeconomic burden to the healthcare system, and has major psychological and physical impacts on the affected individual. VLU often occurs in association with post-thrombotic syndrome, advanced chronic venous disease, varicose veins, and venous hypertension. Several demographic, genetic, and environmental factors could trigger chronic venous disease with venous dilation, incompetent valves, venous reflux, and venous hypertension. Endothelial cell injury and changes in the glycocalyx, venous shear-stress, and adhesion molecules could be initiating events in VLU. Increased endothelial cell permeability and leukocyte infiltration, and increases in inflammatory cytokines, matrix metalloproteinases (MMPs), reactive oxygen and nitrogen species, iron deposition, and tissue metabolites also contribute to the pathogenesis of VLU. Treatment of VLU includes compression therapy and endovenous ablation to occlude the axial reflux. Other interventional approaches such as subfascial endoscopic perforator surgery and iliac venous stent have shown mixed results. With good wound care and compression therapy, VLU usually heals within 6 months. VLU healing involves orchestrated processes including hemostasis, inflammation, proliferation, and remodeling and the contribution of different cells including leukocytes, platelets, fibroblasts, vascular smooth muscle cells, endothelial cells, and keratinocytes as well as the release of various biomolecules including transforming growth factor-β, cytokines, chemokines, MMPs, tissue inhibitors of MMPs (TIMPs), elastase, urokinase plasminogen activator, fibrin, collagen, and albumin. Alterations in any of these physiological wound closure processes could delay VLU healing. Also, these histological and soluble biomarkers can be used for VLU diagnosis and assessment of its progression, responsiveness to healing, and prognosis. If not treated adequately, VLU could progress to non-healed or granulating VLU, causing physical immobility, reduced quality of life, cellulitis, severe infections, osteomyelitis, and neoplastic transformation. Recalcitrant VLU shows prolonged healing time with advanced age, obesity, nutritional deficiencies, colder temperature, preexisting venous disease, deep venous thrombosis, and larger wound area. VLU also has a high, 50-70% recurrence rate, likely due to noncompliance with compression therapy, failure of surgical procedures, incorrect ulcer diagnosis, progression of venous disease, and poorly understood pathophysiology. Understanding the molecular pathways underlying VLU has led to new lines of therapy with significant promise including biologics such as bilayer living skin construct, fibroblast derivatives, and extracellular matrices and non-biologic products such as poly-N-acetyl glucosamine, human placental membranes amnion/chorion allografts, ACT1 peptide inhibitor of connexin 43, sulodexide, growth factors, silver dressings, MMP inhibitors, and modulators of reactive oxygen and nitrogen species, the immune response and tissue metabolites. Preventive measures including compression therapy and venotonics could also reduce the risk of progression to chronic venous insufficiency and VLU in susceptible individuals.

An audience survey of practice relating to pain in the management of chronic venous leg ulcers

Venous leg ulcers (VLU) respond well to compression, yet many ulcers remain unhealed after 1 year. Practitioners could be reluctant to apply compression to patients with significant ulcer pain. This study aimed to capture the views of practitioners on compression therapy for patients with painful VLU. A survey was conducted at a UK meeting in 2019 using handheld voting pads to capture the anonymous responses to four questions to which a mean of 90 practitioners responded. Nearly 40% of practitioners treat six or more patients a day with painful lower-limb ulcers. Some 80% felt confident in managing patients with painful ulcers; yet, most practitioners suggested they would refer onward for pain management. Some 40% would omit or reduce compression therapy as a pain management strategy. This survey supports the need for technological solutions that reduce VLU pain so that patients receive effective compression therapy.