Matrix metalloproteinase (MMP)-1 and MMP-2, but not COX-2 serve as additional predictors for chronic venous ulcer healing

Prognostic factors for delayed healing of complex wounds in adults: A scoping review

Complex or hard-to-heal wounds continue to be a challenge because of the negative impact they have on patients, caregivers, and all the associated costs. This study aimed to identify prognostic factors for the delayed healing of complex wounds. Five databases and grey literature were the sources used to research adults with pressure ulcers/injuries, venous leg ulcers, critical limb-threatening ischaemia, or diabetic foot ulcers and report the prognostic factors for delayed healing in all care settings. In the last 5 years, a total of 42 original peer-reviewed articles were deemed eligible for this scoping review that followed the JBI recommendations and checklist PRISMA-ScR. The most frequent prognostic factors found with statistical significance coinciding with various wound aetiologies were: gender (male), renal disease, diabetes, peripheral arterial disease, the decline in activities of daily life, wound duration, wound area, wound location, high-stage WIfI classification, gangrene, infection, previous ulcers, and low ankle brachial index. It will be essential to apply critical appraisal tools and assessment risk of bias to the included studies, making it possible to make recommendations for clinical practice and build prognostic models. Future studies are recommended because the potential for healing through identification of prognostic factors can be determined, thus allowing an appropriate therapeutic plan to be developed.

The Impact of Prolonged Inflammation on Wound Healing

The treatment of chronic wounds still challenges modern medicine because of these wounds’ heterogenic pathophysiology. Processes such as inflammation, ischemia and bacterial infection play major roles in the progression of a chronic wound. In recent years, preclinical wound models have been used to understand the underlying processes of chronic wound formation. However, the wound models used to investigate chronic wounds often lack translatability from preclinical models to patients, and often do not take exaggerated inflammation into consideration. Therefore, we aimed to investigate prolonged inflammation in a porcine wound model by using resiquimod, a TLR7 and TLR8 agonist. Pigs received full thickness excisional wounds, where resiquimod was applied daily for 6 days, and untreated wounds served as controls. Dressing change, visual documentation and wound scoring were performed daily. Biopsies were collected for histological as well as gene expression analysis. Resiquimod application on full thickness wounds induced a visible inflammation of wounds, resulting in delayed wound healing compared to non-treated control wounds. Gene expression analysis revealed high levels of IL6, MMP1 and CD68 expression after resiquimod application, and histological analysis showed increased immune cell infiltration. By using resiquimod, we were able to show that prolonged inflammation delayed wound healing, which is often observed in chronic wounds in patients. The model we used shows the importance of inflammation in wound healing and gives an insight into the progression of chronic wounds.

A regenerative approach to the pharmacological management of hard-to-heal wounds

A wound is considered hard-to-heal when, despite the appropriate clinical analysis and intervention, the wound area reduces by less than a third at four weeks and complete healing fails to occur within 12 weeks. The most prevalent hard-to-heal wounds are associated with underlying metabolic diseases or vascular insufficiency and include arterial, venous, pressure and diabetic foot ulcers. Their common features include an abnormal immune response and extended inflammatory phase, a subdued proliferation phase due to cellular insufficiencies and finally an almost non-existent remodeling phase. Advances in wound care technology, tested in both pre-clinical models and clinical trials, have paved the way for improved treatment options, focused on regeneration. These interventions have been shown to limit the extent of ongoing inflammatory damage, decrease bacterial load, promote angiogenesis and deposition of granulation tissue, and stimulate keratinocyte migration thereby promoting re-epithelialization in these wounds. The current review discusses these hard-to-heal wounds in the context of their underlying pathology and potential of advanced treatment options, which if applied promptly as a standard of care, could reduce morbidity, promote quality of life, and alleviate the burden on a strained health system.

Hydro-responsive wound dressings for treating hard-to-heal wounds: a narrative review of the clinical evidence

A break in skin integrity must be repaired as quickly as possible to avoid excess blood and fluid loss, and to minimise the onset of infection. Hard-to-heal wounds, in which the progression of the wound healing response is compromised, present several challenges to healing (for example, the presence of devitalised tissue acting as a physical barrier to healing and as a focus for bacterial contamination with the potential for subsequent infection). The objective of this article is to present, as a narrative review, the clinical evidence supporting the use of a unique hydro-responsive wound dressing (HydroClean, HRWD1, PAUL HARTMANN AG, Germany). The dressing provides a simple treatment option to address a number of clinical challenges clinicians must overcome in order to facilitate wound healing progression. These studies demonstrated that this product supported successful debridement/cleansing of a wide variety of wounds, including hard-to-heal wounds, enabled wound bed preparation, and lead to positive healing outcomes, including in wounds that previously had failed to heal. The simplicity of using HRWD1 as a single dressing can help clinicians overcome a variety of challenges when treating both acute and hard-to-heal wounds, which, with the benefit of proven patient outcomes, could make it an ideal choice for a first-line treatment.

New Insights on the Effects of Dietary Omega-3 Fatty Acids on Impaired Skin Healing in Diabetes and Chronic Venous Leg Ulcers

Long-chain Omega-3 polyunsaturated fatty acids (Omega-3 PUFAs) are widely recognized as powerful negative regulators of acute inflammation. However, the precise role exerted by these dietary compounds during the healing process is still largely unknown, and there is increasing interest in understanding their specific effects on the implicated cells/molecular factors. Particular attention is being focused also on their potential clinical application in chronic pathologies characterized by delayed and impaired healing, such as diabetes and vascular diseases in lower limbs. On these bases, we firstly summarized the current knowledge on wound healing (WH) in skin, both in normal conditions and in the setting of these two pathologies, with particular attention to the cellular and molecular mechanisms involved. Then, we critically reviewed the outcomes of recent research papers investigating the activity exerted by Omega-3 PUFAs and their bioactive metabolites in the regulation of WH in patients with diabetes or venous insufficiency and showing chronic recalcitrant ulcers. We especially focused on recent studies investigating the mechanisms through which these compounds may act. Considerations on the optimal dietary doses are also reported, and, finally, possible future perspectives in this area are suggested.

Hybrid fusion protein as a dual protease inhibitor for the healing of chronic wounds

Diseases bring about the need for interventions that pinpoint each specific aspect of the illness. Commonly, remission of a complex disease is accomplished by mixing treatments, medications, and therapeutics together in a fashion where they may negatively interact with each other or never arrive at the diseased site as a systemic heterogeneous mixture. Chronic wounds display intricacy as they are very localized and have their own environment where tissue deconstruction due to high levels of numerous proteases outweighs normal tissue reconstruction. This idea leads to the necessity of a protein that contains low diffusivity rates for localized treatment, strength against high concentrations of proteolytic species that lead to degradation of short chain peptides, while encompassing broad inhibitory effects against multiple proteases. Elastin-like peptides are an attractive, thermoresponsive, protein-based drug delivery partner as they contain low diffusivity and serve as a stable architecture for short chain peptide fusion. In this project, a novel elastin-like peptide-based protein has been created to target the inhibition of both human neutrophil elastase and matrix metalloprotease-2. As a biologic, this is unique as it is a protein with specific biological activities against multiple proteases, ultimately displaying the potential to mix and match differing biologically active peptides within one amino acid sequence.