Doxycycline speeds up healing of chronic venous ulcers

Glycocalyx disruption, endothelial dysfunction and vascular remodeling as underlying mechanisms and treatment targets of chronic venous disease

The glycocalyx is an essential structural and functional component of endothelial cells. Extensive hemodynamic changes cause endothelial glycocalyx disruption and vascular dysfunction, leading to multiple arterial and venous disorders. Chronic venous disease (CVD) is a common disorder of the lower extremities with major health and socio-economic implications, but complex pathophysiology. Genetic aberrations accentuated by environmental factors, behavioral tendencies, and hormonal disturbances promote venous reflux, valve incompetence, and venous blood stasis. Increased venous hydrostatic pressure and changes in shear-stress cause glycocalyx injury, endothelial dysfunction, secretion of adhesion molecules, leukocyte recruitment/activation, and release of cytokines, chemokines, and hypoxia-inducible factor, causing smooth muscle cell switch from contractile to synthetic proliferative phenotype, imbalance in matrix metalloproteinases (MMPs), degradation of collagen and elastin, and venous tissue remodeling, leading to venous dilation and varicose veins. In the advanced stages of CVD, leukocyte infiltration of the vein wall causes progressive inflammation, fibrosis, disruption of junctional proteins, accumulation of tissue metabolites and reactive oxygen and nitrogen species, and iron deposition, leading to skin changes and venous leg ulcer (VLU). CVD management includes compression stockings, venotonics, and surgical intervention. In addition to its antithrombotic and fibrinolytic properties, literature suggests sulodexide benefits in reducing inflammation, promoting VLU healing, improving endothelial function, exhibiting venotonic properties, and inhibiting MMP-9. Understanding the role of glycocalyx, endothelial dysfunction, and vascular remodeling should help delineate the underlying mechanisms and develop improved biomarkers and targeted therapy for CVD and VLU.

Development strategy of novel drug formulations for the delivery of doxycycline in the treatment of wounds of various etiologies

Doxycycline hyclate (DOXH) is a broad-spectrum antibiotic derived synthetically from tetracycline. Despite its use in clinical practice for more than 40 years, DOXH remains an effective antibiotic with retained activity. The potential advantages of DOXH for wound healing therapy include its mechanisms of action, such as anti-inflammatory effects, antioxidant properties, modulation of cellular processes, stimulation of collagen synthesis, and antimicrobial activity. As current standards of care aim to improve wound healing by promoting rapid closure, a relevant direction is the development of novel DOXH formulations for parenteral delivery that enhance both skin regeneration and control of infectious conditions. Oral delivery is the most common and commercially available route for administering DOXH therapeutic agents. However, parenteral delivery of DOXH, where the antibiotic substance is not in a solid state (as in powdered or compressed solid form) but rather dissolved in any carrier, presents challenges regarding DOX solubility and the stability of DOXH solutions, which are major factors complicating the development of new formulations for parenteral administration. This review discusses the achievements in research strategies and the development of new pharmaceutical formulations for the delivery of doxycycline in the treatment of wounds of various etiologies.

Metalloproteases in Pain Generation and Persistence: A Possible Target?

Matrix metalloproteinases (MMPs) are a large family of zinc-dependent proteolytic enzymes associated with extracellular matrix protein turnover and tissue degradation. They participate to many different physiological reactions but are also hyperactivated in several diseases. Various literature studies have documented that MMPs play a role in the modulation of neuropathic and nociceptive pain. The heterogeneity of clinical and pre-clinical data is an important issue in this experimental context. Despite the presence of a good number of studies on MMP inhibitors, these drugs showed scarce efficacy and relevant side effects. In the present manuscript, we reviewed studies in the literature that define a possible role of MMPs in pain and the effects of their modulation.

Molecular Determinants of Chronic Venous Disease: A Comprehensive Review

Chronic Venous Disease (CVD) refers to several pathological and hemodynamic alterations of the veins of lower limbs causing a wide range of symptoms and signs with a high prevalence in the general population and with disabling consequences in the most severe forms. The etiology and pathophysiology of CVD is complex and multifactorial, involving genetic, proteomic, and cellular mechanisms that result in changes to the venous structure and functions. Expressions of several genes associated with angiogenesis, vascular development, and the regulation of veins are responsible for the susceptibility to CVD. Current evidence shows that several extracellular matrix alterations (ECM) could be identified and in some cases pharmacologically targeted. This review shows the most up to date information on molecular determinants of CVD in order to provide a complete overview of the current knowledge on this topic. In particular, the article explores the genetic influence, the hormonal influence, ECM imbalance, and histopathology of CVD and the role of endothelial dysfunction in CVD.

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.

Wound Pain and Wound Healing Biomarkers From Wound Exudate: A Scoping Review

PURPOSE

Effective management of wound pain is essential for optimal wound healing. Nevertheless, the outcomes of wound pain interventions are based on subjective measures, which can prove problematic in patients with cognitive impairment. Identification of biomarkers associated with wound pain and wound healing can be used to more objectively estimate wound pain and contribute to the development of precise management options to reduce wound pain and promote wound healing. This scoping review aimed to identify wound pain and wound healing biomarkers from wound exudates and to describe different wound collection methods to identify these biomarkers.

METHODS

We searched the literature (PROSPERO database registration number: CRD42018103843) via a scoping review.

SEARCH STRATEGY

The PubMed database was searched for articles that explored relationships between cutaneous wound pain, wound healing, and biomolecules. Inclusion criteria were articles that reported original data, used adult human samples, and were published in English.

FINDINGS

Twenty-one articles were retrieved: 17 investigated molecules from wound exudate associated with wound healing status, and 4 reported molecules associated with wound pain. The most frequently observed wound pain biomarkers were proinflammatory cytokines; the most frequently observed wound healing biomarkers were proteases including those in the matrix metalloproteinase family. Six wound exudate collection methods were identified to extract potential wound pain and wound healing biomarkers from wound exudate.

IMPLICATIONS

The results can guide future wound exudate research to validate these wound pain and wound healing biomarkers and to develop therapies targeting these biomarkers to reduce wound pain and promote wound healing.

Carbopol-olive oil-based bigel drug delivery system of doxycycline hyclate for the treatment of acne

OBJECTIVE

The objective of this study was to prepare and evaluate the doxycycline hyclate containing bigel for the effective treatment of acne.

METHODS

Bigels are biphasic systems formed by water-based hydrogels and oil-based organogel. Carbopol 940 was used to prepare the hydrogel phase, whereas Span-60 and olive oil for the oleogel phase.

RESULTS

The microstructure of bigel confirmed the oil in water type emulsion formation. The average droplet size of formulations was found 15-50 µm, and a bell-shaped droplet distribution curve, rheological, or viscosity studies suggested that the consistency and stability of bigel decrease with high organogel concentration. Three formulations (F1, F2, and F3) of the different ratios of hydrogel:oleogel (60:40, 70:30, and 80:20) were prepared in which F1 was less stable compared to F2 and F3. The drug content of F2 and F3 was respectively 79.94 and 71.33%. Formulation F2 was found more effective as compared to F3 based on in vitro drug release studies. Bigel also showed better results during in vivo studies at the rabbit ear model, which reduce acne diameter up to 1.10 mm from 4.9 mm while gel reduced it up to 1.20 mm.

Data Recorded in Real Life Support the Safety of Nattokinase in Patients with Vascular Diseases

Nattokinase (NK) is a serine protease enzyme with fibrinolytic activity. Even if it could be used for the treatment of several diseases, no data have been published supporting its use patients who underwent vascular surgery. In this study, we evaluated both the efficacy and the safety of nattokinase (100 mg/day per os) in patients admitted to vascular surgery. Patients were of both sexes, >18 years of age, with vascular diseases (i.e., deep vein thrombosis, superficial vein thrombosis, venous insufficiency), and naïve to specific pharmacological treatments (anticoagulants or anti-platelets). Patients were divided into three groups. Group 1: patients with deep vein thrombosis, treated with fondaparinux plus nattokinase. Group 2: patients with phlebitis, treated with enoxaparin plus nattokinase. Group 3: patients with venous insufficiency after classical surgery, treated with nattokinase one day later. During the study, we enrolled 153 patients (age 22–92 years), 92 females (60.1%) and 61 males (39.9%;), and documented that nattokinase was able to improve the clinical symptoms (p < 0.01) without the development of adverse drug reactions or drug interactions. Among the enrolled patients, during follow-up, we did not record new cases of vascular diseases. Attention to patients’ clinical evolution, monitoring of the INR, and timely and frequent adjustment of dosages represent the cornerstones of the safety of care for patients administered fibrinolytic drugs as a single treatment or in pharmacological combination. Therefore, we can conclude that the use of nattokinase represents an efficient and safe treatment able to both prevent and treat patients with vascular diseases.

Mechanisms of Lower Extremity Vein Dysfunction in Chronic Venous Disease and Implications in Management of Varicose Veins

Chronic venous disease (CVD) is a common venous disorder of the lower extremities. CVD can be manifested as varicose veins (VVs), with dilated and tortuous veins, dysfunctional valves and venous reflux. If not adequately treated, VVs could progress to chronic venous insufficiency (CVI) and lead to venous leg ulcer (VLU). Predisposing familial and genetic factors have been implicated in CVD. Additional environmental, behavioral and dietary factors including sedentary lifestyle and obesity may also contribute to CVD. Alterations in the mRNA expression, protein levels and proteolytic activity of matrix metalloproteinases (MMPs) have been detected in VVs and VLU. MMP expression/activity can be modulated by venous hydrostatic pressure, hypoxia, tissue metabolites, and inflammation. MMPs in turn increase proteolysis of different protein substrates in the extracellular matrix particularly collagen and elastin, leading to weakening of the vein wall. MMPs could also promote venous dilation by increasing the release of endothelium-derived vasodilators and activating potassium channels, leading to smooth muscle hyperpolarization and relaxation. Depending on VVs severity, management usually includes compression stockings, sclerotherapy and surgical removal. Venotonics have also been promoted to decrease the progression of VVs. Sulodexide has also shown benefits in VLU and CVI, and recent data suggest that it could improve venous smooth muscle contraction. Other lines of treatment including induction of endogenous tissue inhibitors of metalloproteinases (TIMPs) and administration of exogenous synthetic inhibitors of MMPs are being explored, and could provide alternative strategies in the treatment of CVD.

Doxycycline Hyclate Modulates Antioxidant Defenses, Matrix Metalloproteinases, and COX-2 Activity Accelerating Skin Wound Healing by Secondary Intention in Rats

The main objective of this study was to investigate the action of doxycycline hyclate (Dx) in the skin wound healing process in Wistar rats. We investigated the effect of Dx on inflammatory cell recruitment and production of inflammatory mediators via in vitro and in vivo analysis. In addition, we analyzed neovascularization, extracellular matrix deposition, and antioxidant potential of Dx on cutaneous repair in Wistar rats. Male animals (n = 15) were divided into three groups with five animals each (protocol: 72/2017), and three skin wounds (12 mm diameter) were created on the back of the animals. The groups were as follows: C, received distilled water (control); Dx1, doxycycline hyclate (10 mg/kg/day); and Dx2, doxycycline hyclate (30 mg/kg/day). The applications were carried out daily for up to 21 days, and tissues from different wounds were removed every 7 days. Our in vitro analysis demonstrated that Dx led to macrophage proliferation and increased N-acetyl-β-D-glucosaminidase (NAG) production, besides decreased cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and metalloproteinases (MMP), which indicates that macrophage activation and COX-2 inhibition are possibly regulated by independent mechanisms. In vivo, our findings presented increased cellularity, blood vessels, and the number of mast cells. However, downregulation was observed in the COX-2 and PGE2 expression, which was limited to epidermal cells. Our results also showed that the downregulation of this pathway benefits the oxidative balance by reducing protein carbonyls, malondialdehyde, nitric oxide, and hydrogen peroxide (H2O2). In addition, there was an increase in the antioxidant enzymes (catalase and superoxide dismutase) after Dx exposure, which demonstrates its antioxidant potential. Finally, Dx increased the number of types I collagen and elastic fibers and reduced the levels of MMP, thus accelerating the closure of skin wounds. Our findings indicated that both doses of Dx can modulate the skin repair process, but the best effects were observed after exposure to the highest dose.

Potential effectiveness and adverse implications of repurposing doxycycline in COVID-19 treatment

Introduction: COVID-19 infection with no known-specific drugs or vaccines has impacted mankind and has become beyond precedence. Currently, re-purposing of existing drugs is the only therapeutic option for managing COVID-19 symptoms and associated co-infections to reduce mortality. Antimicrobials as varied as antiparasitic, antiviral, and antibiotics are under various stages of evaluation.Areas covered: Recently, doxycycline, a broad-spectrum antibiotic that has also reported antiviral and anti-inflammatory properties was widely investigated in clinical trials, either alone or in combination with other drugs, and repurposed for COVID-19 treatment. In the review, the potential therapeutic applications of doxycycline in COVID-19 treatment and its potential adverse implications with respect to antimicrobial resistance bestowed by repurposing the antibiotic have been expounded.Expert opinion: 'Fighting disease with already existing antibiotics' and 'antimicrobial resistance progression' are like two arms of a balance that has to be carefully equilibrated. Any imbalance by the inappropriate or indiscriminate use of the repurposed drugs would cause a disastrous increase in antimicrobial resistance (AMR). Hence, cautious parallel assessment of potential long-term consequences of AMR is of great importance to mankind as its impacts would prevail even after the current pandemic.

Strategies and challenges in the treatment of chronic venous leg ulcers

Evaluating patients with chronic venous leg ulcers (CVLUs) is essential to find the underlying etiology. The basic tenets in managing CVLUs are to remove the etiological causes, to address systemic and metabolic conditions, to examine the ulcers and artery pulses, and to control wound infection with debridement and eliminating excessive pressure on the wound. The first-line treatments of CVLUs remain wound care, debridement, bed rest with leg elevation, and compression. Evidence to support the efficacy of silver-based dressings in healing CVLUs is unavailable. Hydrogen peroxide is harmful to the growth of granulation tissue in the wound. Surgery options include a high ligation with or without stripping or ablation of the GSVs depending on venous reflux or insufficiency. Yet, not all CVLUs are candidates for surgical treatment because of comorbidities. When standard care of wound for 4 wk failed to heal CVLUs effectively, use of advanced wound care should be considered based on the available evidence. Negative pressure wound therapy facilitates granulation tissue development, thereby helping closure of CVLUs. Autologous split-thickness skin grafting is still the gold standard approach to close huge CVLUs. Hair punch graft appears to have a better result than traditional hairless punch graft for CVLUs. Application of adipose tissue or placenta-derived mesenchymal stem cells is a promising therapy for wound healing. Autologous platelet-rich plasma provides an alternative strategy for surgery for safe and natural healing of the ulcer. The confirmative efficacy of current advanced ulcer therapies needs more robust evidence.

Strategies and challenges in the treatment of chronic venous leg ulcers

Evaluating patients with chronic venous leg ulcers (CVLUs) is essential to find the underlying etiology. The basic tenets in managing CVLUs are to remove the etiological causes, to address systemic and metabolic conditions, to examine the ulcers and artery pulses, and to control wound infection with debridement and eliminating excessive pressure on the wound. The first-line treatments of CVLUs remain wound care, debridement, bed rest with leg elevation, and compression. Evidence to support the efficacy of silver-based dressings in healing CVLUs is unavailable. Hydrogen peroxide is harmful to the growth of granulation tissue in the wound. Surgery options include a high ligation with or without stripping or ablation of the GSVs depending on venous reflux or insufficiency. Yet, not all CVLUs are candidates for surgical treatment because of comorbidities. When standard care of wound for 4 wk failed to heal CVLUs effectively, use of advanced wound care should be considered based on the available evidence. Negative pressure wound therapy facilitates granulation tissue development, thereby helping closure of CVLUs. Autologous split-thickness skin grafting is still the gold standard approach to close huge CVLUs. Hair punch graft appears to have a better result than traditional hairless punch graft for CVLUs. Application of adipose tissue or placenta-derived mesenchymal stem cells is a promising therapy for wound healing. Autologous platelet-rich plasma provides an alternative strategy for surgery for safe and natural healing of the ulcer. The confirmative efficacy of current advanced ulcer therapies needs more robust evidence.

Antibiotics Affect ROS Production and Fibroblast Migration in an In-vitro Model of Sinonasal Wound Healing

Introduction: Antibiotics are often administered to patients perioperatively and have been shown to affect ROS production of nasal cells in vitro, but their effect in the setting of active wound healing remains unclear. Reactive oxygen species (ROS) are known to play a significant role in wound healing. This study analyzed a broad array of antibiotics used after sinus surgery to assess their effect on wound healing and ROS production in vitro. It was hypothesized that ROS production would be affected by these antibiotics and there would be a negative relationship between ROS activity and cell migration speed. Methods: Monolayers of primary human nasal epithelial cells (HNEC) and primary fibroblasts were disrupted with a linear wound, treated with 10 different antibiotics or a ROS inhibitor and observed over 36 h in a controlled environment using confocal microscopy. ROS activity and migration speed of the wound edge were measured at regular intervals. The relationship between the two parameters was analyzed using mixed linear modeling. Results: Performing a linear scratch over the cell monolayers produced an immediate increase in ROS production of ~35% compared to unscratched controls in both cell types. Incubation with mitoquinone and the oxazolidinone antibiotic linezolid inhibited ROS activity in both fibroblasts and HNEC in association with slowed fibroblast cell migration (p < 0.05). Fibroblast cell migration was also reduced in the presence of clarithromycin and mupirocin (p < 0.05). A significant correlation was seen between ROS suppression and cell migration rate in fibroblasts for mitoquinone and all antibiotics except for azithromycin and doxycycline, where no clear relationship was seen. Treatments that slowed fibroblast cell migration compared to untreated controls showed a significant correlation with ROS suppression (p < 0.05). Conclusion: Increased ROS production in freshly wounded HNEC and fibroblast cell monolayers was suppressed in the presence of antibiotics, in correlation with reduced fibroblast cell migration. In contrast, HNEC cell migration was not significantly affected by any of the antibiotics tested. This differential effect of antibiotics on fibroblast and HNEC migration might have clinical relevance by reducing adhesion formation without affecting epithelial healing in the postoperative setting.

Expression of MMP-2, MMP-9, and NGAL in Tissue and Serum of Patients with Vascular Aneurysms and Their Modulation by Statin Treatment: A Pilot Study

BACKGROUND

Matrix metalloproteinases (MMPs) are involved in vascular wall degradation, and drugs able to modulate MMP activity can be used to prevent or treat aneurysmal disease. In this study, we evaluated the effects of statins on MMP-2, MMP-9, and neutrophil gelatinase-associated lipocalin (NGAL) in both plasma and tissue in patients with aneurysmal disease.

METHODS

We performed a prospective, single-blind, multicenter, control group clinical drug trial on 184 patients of both sexes >18 years old with a diagnosis of arterial aneurysmal disease. Enrolled patients were divided into two groups: Group I under statin treatment and Group II not taking statins. In addition, 122 patients without aneurysmal disease and under statin treatment were enrolled as a control group (Group III). The expression of MMPs and NGAL in plasma was evaluated using ELISA, while their expression in endothelial tissues was evaluated using Western blot.

RESULTS

The ELISA test revealed greater plasma levels (p < 0.01) of MMPs and NGAL in Groups I and II vs. Group III. Western blot analysis showed higher expression (p < 0.01) of MMPs and NGAL in Group II vs. Group I, and this increase was significantly higher (p < 0.01) in patients treated with low potency statins compared to high potency ones.

CONCLUSIONS

MMPs and NGAL seem to play a major role in the development of aneurysms, and their modulation by statins suggests that these drugs could be used to prevent arterial aneurysmal disease.

Nano-hydrogel embedded with quercetin and oleic acid as a new formulation in the treatment of diabetic foot ulcer: A pilot study

Wound healing, especially diabetic ones, is a relevant clinical problem, so it is not surprising that surgical procedures are often needed. To overcome invasive procedures, several strategies with drugs or natural compound are used. Recently, in an experimental study, we described an increase in keratinocyte proliferation after their exposition to quercetin plus oleic acid. In the present clinical study, we evaluated both the clinical efficacy and the safety of nano-hydrogel embedded with quercetin and oleic acid in the treatment of lower limb skin wound in patients with diabetes mellitus (DM). Fifty-six DM patients (28 men and 28 women, mean age 61.7 ± 9.2 years) unsuccessfully treated with mechanical compression were enrolled and randomised to receive an add on treatment with hyaluronic acid (0.2%) or nano-hydrogel embedded with quercetin and oleic acid. The treatment with nano-hydrogel embedded with quercetin and oleic acid significantly (P < .01) reduced the wound healing time, in comparison to hyaluronic acid (0.2%) without developing of adverse drug reactions, suggesting that this formulation could be used in the management of wound healing even if other clinical trials must be performed in order to validate this observation.

Local release of metalloproteinases and their inhibitors after a successful revascularisation procedure

An altered balance between metalloproteinases (MMPs) and their inhibitor tissue inhibitor of metalloproteinases (TIMPs) may influence the healing process of a minor amputation following a successful vein graft. To speed up this process, negative pressure wound therapy (NPWT) and advanced moist wound dressing have been proposed. We determined the systemic and local release of MMP-1, -2, -3, -9, TIMP-1, and TIMP-2 by enzyme linked immunosorbent assay (ELISA) technique and their influences in the healing process in 26 patients who underwent minor amputation after a successful revascularisation procedure. Twelve patients (group 1) were medicated with NPWT and 14 (group 2) with advanced moist wound dressing. Plasma samples were collected on the morning of surgery and thereafter at 1, 3, and 5 months; exudates were collected 3 days after surgery when amputation was performed and thereafter at 1, 3, and 5 months. Fifteen age-matched healthy male volunteers served as controls. All wounds healed in 5 ± 0.5 months. Follow-up plasma and local release of MMP-1, -2, -3, and -9 were overall significantly lower when compared with the preoperative levels, while those of TIMP-1 and -2 were significantly higher with no differences among the groups. Despite no differences in the healing process being observed among the two types of medications, at 1 month the local release of MMP-2 and -9 was significantly lower (P = .013 and .047, respectively) and that of TIMP-1 was significantly higher (P = .042) in group 1 as compared to group 2. A correct and aggressive local approach to the wound is able to promote the healing of the lesion stimulating the extracellular matrix turnover with local MMP/TIMP adequate balance and favouring the creation of granulation tissue. However, a successful restoration of an adequate blood flow remains the key point of a durable and rapid wound healing.

Adjuvant therapies in venous leg ulcer management: A scoping review

Compression therapy is the current evidence-based approach to manage venous leg ulcers (VLU); however, adherence is a major barrier to successful treatment. Combination approaches may relieve the burden of treatment by shortening the time to ulcer healing. This scoping review conducted by Australian researchers aimed to establish the evidence of effectiveness of various adjuvant methods on wound healing and recurrence. Randomized Controlled Trials (RCTs), and Systematic Reviews (SR) and Meta-Analyses (MA) on VLU management approaches published from January 2015 to December 2018 were included in this review. The articles included in the scoping review were grouped according to the management approaches, including (1) pharmaceutical interventions, (2) surgical interventions, (3) topical agents, (4) the use of devices, and (5) other, such as physiotherapy and psychological interventions. Results of this scoping review indicate that there is a limited high-quality evidence of effectiveness in most adjuvant therapies on wound healing and recurrence. Given the low-quality evidence observed in this scoping review for adjuvant treatments, the implication for practice is that current management guidelines be followed. Further rigorous studies have the potential to produce better quality evidence. Quality of evidence can be improved by ensuring large sample sizes of a single etiology wounds, standardizing reporting outcomes, and maintaining detailed and evidence-based protocols in physiological or psychological interventions.

Systemic therapies for leg ulcers

Successful management of patients with leg ulcers requires identification of the underlying etiology, with subsequent initiation of causal treatment, if feasible. Supplementary measures of first choice include stage-adjusted wound treatment, usually combined with compression therapy. The significance of systemic drugs has been the subject of controversial debate, depending on the underlying cause of the condition. The present review article is therefore meant to highlight current aspects of systemic drug therapies for the treatment of leg ulcers associated with chronic venous insufficiency, peripheral arterial disease, livedoid vasculopathy, vasculitis, necrobiosis lipoidica, calciphylaxis and pyoderma gangrenosum. In summary, the majority of therapeutic options presented herein are used off-label. While systemic drugs are promising options for the more common types of wounds such as venous, mixed or arterial leg ulcers, they do not represent the current standard of treatment. By contrast, systemic agents play a key role in the management of many of the other disorders presented herein. These agents primarily include immunomodulatory and rheological drugs used to expedite wound healing.

Protease activity as a prognostic factor for wound healing in venous leg ulcers

BACKGROUND

Venous leg ulcers (VLUs) are a common type of complex wound that have a negative impact on people's lives and incur high costs for health services and society. It has been suggested that prolonged high levels of protease activity in the later stages of the healing of chronic wounds may be associated with delayed healing. Protease modulating treatments have been developed which seek to modulate protease activity and thereby promote healing in chronic wounds.

OBJECTIVES

To determine whether protease activity is an independent prognostic factor for the healing of venous leg ulcers.

SEARCH METHODS

In February 2018, we searched the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid Embase and CINAHL.

SELECTION CRITERIA

We included prospective and retrospective longitudinal studies with any follow-up period that recruited people with VLUs and investigated whether protease activity in wound fluid was associated with future healing of VLUs. We included randomised controlled trials (RCTs) analysed as cohort studies, provided interventions were taken into account in the analysis, and case-control studies if there were no available cohort studies. We also included prediction model studies provided they reported separately associations of individual prognostic factors (protease activity) with healing. Studies of any type of protease or combination of proteases were eligible, including proteases from bacteria, and the prognostic factor could be examined as a continuous or categorical variable; any cut-off point was permitted. The primary outcomes were time to healing (survival analysis) and the proportion of people with ulcers completely healed; the secondary outcome was change in ulcer size/rate of wound closure. We extracted unadjusted (simple) and adjusted (multivariable) associations between the prognostic factor and healing.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion at each stage, and undertook data extraction, assessment of risk of bias and GRADE assessment. We collected association statistics where available. No study reported adjusted analyses: instead we collected unadjusted results or calculated association measures from raw data. We calculated risk ratios when both outcome and prognostic factor were dichotomous variables. When the prognostic factor was reported as continuous data and healing outcomes were dichotomous, we either performed regression analysis or analysed the impact of healing on protease levels, analysing as the standardised mean difference. When both prognostic factor and outcome were continuous data, we reported correlation coefficients or calculated them from individual participant data.We displayed all results on forest plots to give an overall visual representation. We planned to conduct meta-analyses where this was appropriate, otherwise we summarised narratively.

MAIN RESULTS

We included 19 studies comprising 21 cohorts involving 646 participants. Only 11 studies (13 cohorts, 522 participants) had data available for analysis. Of these, five were prospective cohort studies, four were RCTs and two had a type of case-control design. Follow-up time ranged from four to 36 weeks. Studies covered 10 different matrix metalloproteases (MMPs) and two serine proteases (human neutrophil elastase and urokinase-type plasminogen activators). Two studies recorded complete healing as an outcome; other studies recorded partial healing measures. There was clinical and methodological heterogeneity across studies; for example, in the definition of healing, the type of protease and its measurement, the distribution of active and bound protease species, the types of treatment and the reporting of results. Therefore, meta-analysis was not performed. No study had conducted multivariable analyses and all included evidence was of very low certainty because of the lack of adjustment for confounders, the high risk of bias for all studies except one, imprecision around the measures of association and inconsistency in the direction of association. Collectively the research indicated complete uncertainty as to the association between protease activity and VLU healing.

AUTHORS' CONCLUSIONS

This review identified very low validity evidence regarding any association between protease activity and VLU healing and there is complete uncertainty regarding the relationship. The review offers information for both future research and systematic review methodology.

Cell Based Therapeutic Approach in Vascular Surgery: Application and Review

Multipotent stem cells - such as mesenchymal stem/stromal cells and stem cells derived from different sources like vascular wall are intensely studied to try to rapidly translate their discovered features from bench to bedside. Vascular wall resident stem cells recruitment, differentiation, survival, proliferation, growth factor production, and signaling pathways transduced were analyzed. We studied biological properties of vascular resident stem cells and explored the relationship from several factors as Matrix Metalloproteinases (MMPs) and regulations of biological, translational and clinical features of these cells. In this review we described a translational and clinical approach to Adult Vascular Wall Resident Multipotent Vascular Stem Cells (VW-SCs) and reported their involvement in alternative clinical approach as cells based therapy in vascular disease like arterial aneurysms or peripheral arterial obstructive disease.

Skin tears and risk factors assessment: a systematic review on evidence-based medicine

Skin tears represent a common condition of traumatic wounds, which may be encountered in some categories of individuals at the extremes of age, such as infants and the elderly. Despite the high prevalence and cost of these lesions, there has been little investigation into the risk factors that lead to this condition. The aim of this review was to systematically evaluate the main risk factors involved in development of skin tears. We planned to include all the studies dealing with risk factors related to skin tears. Only publications in English were considered. We excluded all the studies that did not properly fit our research question and those with insufficient data. Of the 166 records found, 24 matched our inclusion criteria. After reading the full-text articles, we decided to exclude seven articles because of the following reasons: (1) not responding properly to our research questions and (2) insufficient data; the final set included 17 articles. From a literature search, we found the following main issues related to risk factors, which have been described in detail in this section: age-related skin changes, dehydration, malnutrition, sensory changes, mobility impairment, pharmacological therapies and mechanical factors related to skin care practices. Our findings clearly show that in frail populations (especially infant and elderly), the stratification risk, as a primary prevention strategy, is an effective tool in avoiding the development of chronic wounds. The development and the implementation of prevention strategies based on appropriate knowledge of the risk factors involved and the adoption of correct techniques during skin care practices could reduce or even avoid the onset of skin tears.

Matrix Metalloproteinases, Vascular Remodeling, and Vascular Disease

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that degrade various proteins in the extracellular matrix (ECM). Typically, MMPs have a propeptide sequence, a catalytic metalloproteinase domain with catalytic zinc, a hinge region or linker peptide, and a hemopexin domain. MMPs are commonly classified on the basis of their substrates and the organization of their structural domains into collagenases, gelatinases, stromelysins, matrilysins, membrane-type (MT)-MMPs, and other MMPs. MMPs are secreted by many cells including fibroblasts, vascular smooth muscle (VSM), and leukocytes. MMPs are regulated at the level of mRNA expression and by activation through removal of the propeptide domain from their latent zymogen form. MMPs are often secreted in an inactive proMMP form, which is cleaved to the active form by various proteinases including other MMPs. MMPs degrade various protein substrates in ECM including collagen and elastin. MMPs could also influence endothelial cell function as well as VSM cell migration, proliferation, Ca²⁺ signaling, and contraction. MMPs play a role in vascular tissue remodeling during various biological processes such as angiogenesis, embryogenesis, morphogenesis, and wound repair. Alterations in specific MMPs could influence arterial remodeling and lead to various pathological disorders such as hypertension, preeclampsia, atherosclerosis, aneurysm formation, as well as excessive venous dilation and lower extremity venous disease. MMPs are often regulated by endogenous tissue inhibitors of metalloproteinases (TIMPs), and the MMP/TIMP ratio often determines the extent of ECM protein degradation and tissue remodeling. MMPs may serve as biomarkers and potential therapeutic targets for certain vascular disorders.

Exudate collection using wound sponges-An easy, non-invasive and reliable method to explore protease activities in ulcers

Proteases are important for wound healing, but in excessive amounts or left uncontrolled, they may cause healing impairment or other severe wound complications. Point-of-care testing for protease activities in wounds may be useful for monitoring the effectiveness of treatment, and for early identification of wounds that potentially fail to heal. Here we describe an easy, noninvasive method to collect wound fluid for evaluating the protease milieu of wounds. Wound fluids were collected using sterile sponges applied between wound surface and normal wound dressing. Wound fluid could be easily squeezed or centrifuged out of the sponges and was tested for gelatinase (MMP-2 and MMP-9) activities by gel zymography. In addition, we measured polymorphonuclear granulocyte elastase levels by ELISA. Both gelatinases were remarkably stable in sponge derived fluids, as no significant loss was observed even when samples were stored for 3 days at room temperature. Protease levels were highly diverse amongst patients and, in some cases, showed substantial variations in the course of the treatment. The here described wound sponge approach represents a patient-friendly and reliable method to collect wound fluid for evaluating wound healing relevant biomarkers, such as matrix metalloproteinases.

Matrix Metalloproteinases in Remodeling of Lower Extremity Veins and Chronic Venous Disease

The veins of the lower extremity are equipped with efficient wall, contractile vascular smooth muscle (VSM), and competent valves in order to withstand the high venous hydrostatic pressure in the lower limb and allow unidirectional movement of deoxygenated blood toward the heart. The vein wall structure and function are in part regulated by matrix metalloproteinases (MMPs). MMPs are zinc-dependent endopeptidases that are secreted as inactive pro-MMPs by different cells in the venous wall including fibroblasts, VSM, and leukocytes. Pro-MMPs are activated by other MMPs, proteinases, and other endogenous and exogenous activators. MMPs degrade various extracellular matrix (ECM) proteins including collagen and elastin, and could affect other cellular processes including endothelium-mediated dilation, VSM cell migration, and proliferation as well as modulation of Ca²⁺ signaling and contraction in VSM. It is thought that increased lower limb venous hydrostatic pressure increases hypoxia-inducible factors and other MMP inducers such as extracellular matrix metalloproteinase inducer, leading to increased MMP expression/activity, ECM protein degradation, vein wall relaxation, and venous dilation. Vein wall inflammation and leukocyte infiltration cause additional increases in MMPs, and further vein wall dilation and valve degradation, that could lead to chronic venous disease and varicose veins (VVs). VVs are often presented as vein wall dilation and tortuosity, incompetent venous valves, and venous reflux. Different regions of VVs show different MMP levels and ECM proteins with atrophic regions showing high MMP levels/activity and little ECM compared to hypertrophic regions with little or inactive MMPs and abundant ECM. Treatment of VVs includes compression stockings, venotonics, sclerotherapy, or surgical removal. However, these approaches do not treat the cause of VVs, and other lines of treatment may be needed. Modulation of endogenous tissue inhibitors of metalloproteinases (TIMPs), and exogenous synthetic MMP inhibitors may provide new approaches in the management of VVs.

Therapeutic effectiveness of a Calendula officinalis extract in venous leg ulcer healing

OBJECTIVE

Non-healing venous leg ulcers (VLUs) have a significant effect on patients' quality of life and substantially increase expenditures in health-care systems. The aim of this study was to evaluate the clinical efficacy of the Calendula officinalis extract, Plenusdermax, in the treatment of VLUs.

METHOD

Patients treated with Calendula officinalis extract (n=38) and control patients (n=19) were evaluated every two weeks for 30 weeks or until their ulcers healed. Assessments included determination of the wound area by planimetry, infection control, and evaluation of the clinical aspects of the wounds. The percentage of healing velocity per week (%HVw), taking the initial area at baseline into account, was also determined.

RESULTS

The proportion of the treatment patients achieving complete epithelialisation was 72 % and 32 % in the treatment and control groups, respectively. The average healing time was approximately 12 weeks in the treatment group and 25 % in control patients. Patients with ulcers treated with Calendula officinalis extract had a significant 4-fold increase in percentage healing velocity per week, 7.4 %, compared with 1.7 % in the control group. No adverse events were observed during the Calendula officinalis extract treatment.

CONCLUSION

Our findings indicate that Calendula officinalis extract is an effective treatment for VLUs.

DECLARATION OF INTEREST

The authors have no conflict of interest.

Matrix metalloproteinases and risk stratification in patients undergoing surgical revascularisation for critical limb ischaemia

Critical limb ischaemia (CLI) is the most advanced form of peripheral artery disease (PAD) and it is often associated with foot gangrene, which may lead to major amputation of lower limbs, and also with a higher risk of death due to fatal cardiovascular events. Matrix metalloproteinases (MMPs) seem to be involved in atherosclerosis, PAD and CLI. Aim of this study was to evaluate variations in MMP serum levels in patients affected by CLI, before and after lower limb surgical revascularisation through prosthetic or venous bypass. A total of 29 patients (7 females and 22 males, mean age 73·4 years, range 65-83 years) suffering from CLI and submitted to lower extremity bypass (LEB) in our Institution were recruited. Seven patients (group I) underwent LEB using synthetic polytetrafluoroethylene (PTFE) graft material and 22 patients (group II) underwent LEB using autogenous veins. Moreover, 30 healthy age-sex-matched subjects were also enrolled as controls (group III). We documented significantly higher serum MMPs levels (P < 0·01) in patients with CLI (groups I and II) with respect to control group (group III). Finally, five patients with CLI (17·2%) showed poor outcomes (major amputations or death), and enzyme-linked immunosorbent assay (ELISA) test showed very high levels of MMP-1 and MMP-8. MMP serum levels seem to be able to predict the clinical outcomes of patients with CLI.

Fondaparinux vs warfarin for the treatment of unsuspected pulmonary embolism in cancer patients

Introduction

In cancer patients, the chest computer tomography (CT) can be used to identify asymptomatic pulmonary embolism (APE). In most cases, these patients are treated with anticoagulant drugs for at least 3 months. The American College of Physicians recommend treatment of these patients as patients with symptomatic pulmonary embolism. In this study, we evaluated and compared the efficacy and safety of fondaparinux vs warfarin in the prevention of unsuspected pulmonary embolism in patients with active cancer.

Materials and methods

A prospective and parallel group study was performed on 64 cancer patients (29 males and 35 females) with APE. A multidetector CT angiography with high spatial and temporal resolution and quality of arterial opacification was used to make the diagnosis. Lung scintigraphy was reserved to selected patients only. Patients were randomized to either the warfarin (Group A) or the fondaparinux (Group B) for 90 days. The first end point of efficacy was the persistence, reduction, or disappearance of thrombosis after 90 days. The second end point was the reappearance of thrombosis after 1 year. The first end point of safety was the development of major bleeding.

Results

We enrolled 32 patients into each treatment group. We reached the first end point of efficacy and safety in Group B which showed that fondaparinux was able to induce the disappearance of thrombotic pulmonary with a lower incidence of major bleeding events compared with warfarin. No difference in the secondary end point was recorded.

Conclusion

We suggest that the treatment of cancer patients with APE can be oriented with the administration of a standard dose of fondaparinux until the next CT lung control (3 months). However, the lack of a randomized clinical trial, including a larger patient cohort, does not allow formulation of final recommendations in these patients. A broader study would be desirable, involving a larger number of patients and a longer follow-up period.

Hepatic ischemia reperfusion injury: A systematic review of literature and the role of current drugs and biomarkers

Hepatic ischemia reperfusion injury (IRI) is not only a pathophysiological process involving the liver, but also a complex systemic process affecting multiple tissues and organs. Hepatic IRI can seriously impair liver function, even producing irreversible damage, which causes a cascade of multiple organ dysfunction. Many factors, including anaerobic metabolism, mitochondrial damage, oxidative stress and secretion of ROS, intracellular Ca(2+) overload, cytokines and chemokines produced by KCs and neutrophils, and NO, are involved in the regulation of hepatic IRI processes. Matrix Metalloproteinases (MMPs) can be an important mediator of early leukocyte recruitment and target in acute and chronic liver injury associated to ischemia. MMPs and neutrophil gelatinase-associated lipocalin (NGAL) could be used as markers of I-R injury severity stages. This review explores the relationship between factors and inflammatory pathways that characterize hepatic IRI, MMPs and current pharmacological approaches to this disease.

Effects of a new nutraceutical substance on clinical and molecular parameters in patients with chronic venous ulceration

Pathophysiological events involved in the onset of chronic venous ulceration (CVU) are inflammation, activation of polymorphonucleates (PMNs) and secretion of proteases such as matrix metalloproteinases (MMPs), which degrade extracellular matrix (ECM) that is a support for vascular and tissutal wall. MMPs, neutrophil gelatinase-associated lipocalin (NGAL) and inflammatory cytokines are overexpressed in CVUs and they could play a central role in pathophysiological mechanisms of skin lesion and delayed wound healing. Bioflavonoids, such as diosmin and other compounds, appear to have several provessel function activities including anti-inflammatory, antioxidant and phlebotonic effects and are widely used in the treatment of chronic venous disease (CVD)-related problems. In this article, we evaluated the effects of Axaven(®) , a new nutraceutical on both clinical and molecular parameters in patients with CVUs. During the study period, 83 patients with CVUs of both sexes were enrolled and divided into two groups: group A (treated group): 25 females and 19 males (median age is 67·7 years) received standard treatment (compression therapy and surgical correction of superficial venous incompetence) + Axaven(®) once a day for 8 months as adjunctive treatment. Group B (control group): 24 females and 15 males (median age is 65·2 years) were treated only with basic treatment according to their clinical conditions. In our study, the administration of Axaven(®) in patients with CVUs was able to decrease inflammatory cytokines, MMPs and NGAL, inducing an improvement of both symptoms with an increase of the speed of wound healing.

Venous aneurysm complicating arteriovenous fistula access and matrix metalloproteinases

Introduction

An arteriovenous fistula (AVF) for placed for hemodialysis may be burdened by one particular complication—the formation of a venous aneurysm. It has been shown that matrix metalloproteinases (MMPs) and neutrophil gelatinase-associated lipocalin (NGAL) could represent markers of disease in both venous and arterial vessels.

Materials and methods

This case study reports a rare case of enormous venous aneurysm-correlated MMP and NGAL levels in a woman with an AVF.

Results

Significantly higher levels of plasma MMP-1, MMP-8, MMP-9, and NGAL were detected in this patient during aneurysmal evaluation before the surgery; these levels significantly decreased 1, 3 and 6 months after surgery.

Conclusion

MMP and NGAL levels could represent a marker of aneurysmal disease, and their plasma evaluation could help physicians to stratify the risk of complications in patients with an AVF.

An uncommon case of arterial aneurysms association with high plasma levels of Matrix Metalloproteinase-9 and Neutrophil Gelatinase-Associated Lipocalin

The association of an axillary artery aneurysm and an abdominal aortic aneurysm is extremely rare. In this study, we describe this association in a 69 year-old-man. We measured this patient’s metalloproteinases (MMPs) and Neutrophil Gelatinase – Associated Lipocalin (NGAL) levels over a three years period before the abdominal aortic aneurysm rupture. We speculate that high serium levels of MMPs and NGAL may have a prognostic role and may predict aneurysm rupture in patients with an uncommon association of arterial aneurysms.

PredyCLU: a prediction system for chronic leg ulcers based on fuzzy logic; part I - exploring the venous side

Chronic leg ulcers (CLUs) are a common occurrence in the western population and are associated with a negative impact on the quality of life of patients. They also cause a substantial burden on the health budget. The pathogenesis of leg ulceration is quite heterogeneous, and chronic venous ulceration (CVU) is the most common manifestation representing the main complication of chronic venous disease (CVD). Prevention strategies and early identification of the risk represent the best form of management. Fuzzy logic is a flexible mathematical system that has proved to be a powerful tool for decision-making systems and pattern classification systems in medicine. In this study, we have elaborated a computerised prediction system for chronic leg ulcers (PredyCLU) based on fuzzy logic, which was retrospectively applied on a multicentre population of 77 patients with CVD. This evaluation system produced reliable risk score patterns and served effectively as a stratification risk tool in patients with CVD who were at the risk of developing CVUs.

A treatment algorithm to identify therapeutic approaches for leg ulcers in patients with sickle cell disease

Sickle cell leg ulcers (SCLUs) are a common complication of sickle cell disease (SCD). Patients who develop ulcers appear to have a more severe haemolysis-associated vasculopathy than individuals who do not develop them, and manifest other complications such as priapism and pulmonary hypertension. SCLUs are slow to heal and often recur, affecting both the emotional and physical well-being of patients. Here we summarise what is known about the pathophysiology of SCLUs, describe available treatment options and propose a treatment algorithm.

The role of adult tissue-derived stem cells in chronic leg ulcers: a systematic review focused on tissue regeneration medicine

Wound healing is an articulated process that can be impaired in different steps in chronic wounds. Chronic leg ulcers are a special type of non-healing wounds that represent an important cause of morbidity and public cost in western countries. Because of their common recurrence after conventional managements and increasing prevalence due to an ageing population, newer approaches are needed. Over the last decade, the research has been focused on innovative treatment strategies, including stem-cell-based therapies. After the initial interest in embryonic pluripotent cells, several different types of adult stem cells have been studied because of ethical issues. Specific types of adult stem cells have shown a high potentiality in tissue healing, in both in vitro and in vivo studies. Aim of this review is to clearly report the newest insights on tissue regeneration medicine, with particular regard for chronic leg ulcers.

Plasma MMP and TIMP evaluation in patients with deep venous thrombosis: could they have a predictive role in the development of post-thrombotic syndrome?

Post-thrombotic syndrome (PTS) is a condition that can develop in about half of the patients with deep vein thrombosis (DVT) of lower limbs. In the present study, we evaluated the expression of inflammatory biomarkers in the early phases of DVT and their correlation with the onset of PTS. Patients were enrolled after the first episode of DVT and were followed up for 1, 4, 8, 12 and 18 months. At each visit, blood sample was collected to evaluate plasma levels of matrix metalloproteinase (MMP)-1,-2,-3,-7,-8 and -9 MMP inhibitors, TIMP-1,-2, neutrophil gelatinase-associated lipocalin (NGAL) and cytokines TNF-α and IL-6. Analysis included 201 patients [86 males (42·79%) and 115 females (57·21%); average age 56 ± 7 years]. Of the 201 patients, 47 (23·38%; 21 males, 26 females) developed PTS during the follow-up period. The control group was made up of 60 individuals without DVT (22 males and 38 females). High plasma levels of MMPs, NGAL and cytokines were recorded during the acute phase after DVT. Moreover, patients with PTS showed higher levels of MMP-1 and MMP-8 with respect to patients without PTS. There is a close relationship between DVT, the individual risk of PTS and specific biomarkers such as MMPs and other related molecules, which may help guide prevention and therapy based on the patient's individual risk profile, and has to be studied in future.

The use of growth factors, CD34(+) cells and fibrin for the management of chronic venous ulcers

Chronic venous ulceration represents a very common event. Current standard treatment includes local wound care with the application of compression. We report the effects of platelet-rich plasma in patients with chronic venous ulcers, which is able to stimulate fibroblasts, macrophages and mesenchymal cells and growth factors in order to achieve re-epithelialisation and neovascularisation within the microenviroment of the wound. We also documented the efficacy of this method as the sole treatment without surgical procedures.

Symptoms in patients with skin changes due to chronic venous insufficiency often lead to emergency care service: an Italian observational study

Chronic venous insufficiency (CVI) is the most advanced form of chronic venous disease (CVD), and is often associated with skin changes such as hyperpigmentation, eczema, lipodermatosclerosis and venous skin ulceration that cause discomfort, pain, sleep disturbances, absenteeism in the workplace, disability and deteriorated quality of life (QoL). The purpose of this study is to evaluate the prevalence of CVI and skin changes in patients who turn to Continuous Assistance Services due to the presence of disturbing symptoms of their condition. Data were evaluated by consulting the medical records, during a 16-month period, available with three Continuous Assistance Services of the Italian territory. The overall population of the referring centres consisted of 1186 patients [739 females (62·31%) and 447 males (37·69%)]. Seventy-nine patients (6·66%) consulted the emergency unit for venous symptoms related to CVD. Patients with more severe disease (CVI, categories C4-C6) represented the majority accounting for 60·75%, while patients with moderate disease (C3) accounted for 35·44% and patients with mild disease (C1-C2 stages) accounted for 3·79%. The main finding of this study is that despite CVI not being a disease that commonly requires medical emergency/urgency intervention, patients with CVI, especially in advanced stage with skin changes, may turn to Continuous Assistance Service for treating bothersome symptoms related to their condition.

Curbing Inflammation in Skin Wound Healing: A Review

Wound healing is a complex regulated process that results in skin scar formation in postnatal mammals. Chronic wounds are major medical problems that can confer devastating consequences. Currently, there are no treatments to prevent scarring. In the early fetus wounds heal without scarring and the healing process is characterized by relatively less inflammation compared to adults; therefore, research aimed at reducing the inflammatory process related to wound healing might speed healing and improve the final scar appearance.

Cell Therapy in Patients with Critical Limb Ischemia

Critical limb ischemia (CLI) represents the most advanced stage of peripheral arterial obstructive disease (PAOD) with a severe obstruction of the arteries which markedly reduces blood flow to the extremities and has progressed to the point of severe rest pain and/or even tissue loss. Recent therapeutic strategies have focused on restoring this balance in favor of tissue survival using exogenous molecular and cellular agents to promote regeneration of the vasculature. These are based on stimulation of angiogenesis by extracellular and cellular components. This review article carries out a systematic analysis of the most recent scientific literature on the application of stem cells in patients with CLI. The results obtained from the detailed analysis of the recent literature data have confirmed the beneficial role of cell therapy in reducing the rate of major amputations in patients with CLI and improving their quality of life.

Aterofisiol(®) in carotid plaque evolution

Background

In patients with carotid stenosis, the risk of plaque rupture is related to the composition of the atherosclerotic plaque rather than to its magnitude. In this regard, we evaluated the effects of a supplement, Aterofisiol,^® containing omega-3 (EPA [eicosapen acid] DHA [docosahexaenoic acid]), vitamin K₂, vitamin B₆, vitamin B₁₂, oligomeric proanthocyanidins (OPC) and resveratrol on the composition of atherosclerotic plaque and on neurological symptoms in patients with carotid stenosis undergoing carotid endarterectomy.

Methods

The study was randomized, prospective, and double-blinded. Eligible patients were of both sexes, with carotid stenosis >70% who underwent endarterectomy. Enrolled patients were randomly allocated to receive either one tablet of acetylsalicylic acid 100 mg (Cardioaspirin^®) + one tablet of Aterofisiol every 24 hours or one tablet of Cardioaspirin + one tablet of placebo every 24 hours. Each treatment was started 30 days before the surgery and was stopped 5 days before the surgery. The plaques were removed “en bloc” using standard surgical technique.

Results

During the study period, 214 patients (135 men and 79 women) were enrolled for intent-to-treat and randomized in two groups: Group A: 107 patients (68 men and 39 women) were treated with Cardioaspirin + Aterofisiol. Group B: 107 patients (67 men and 40 women) were treated with Cardioaspirin + placebo. At the end of the study, 202 patients participated fully (103 patients in Group A and 99 patients in Group B), making up the protocol evaluation population (94.4%). The mean lipid content of removed plaques was significantly lower (P<0.05) in Group A. We recorded a significantly lower incidence of neurological symptoms in Group A in comparison with Group B (P<0.05).

Conclusion

In the study, Aterofisiol showed to be effective in reducing the amounts of cholesterol and lipids in the plaques and in reducing adverse neurological events in the study group with respect to controls.

Glu-Trp-ONa or its acylated analogue (R-Glu-Trp-ONa) administration enhances the wound healing in the model of chronic skin wounds in rabbits

The management of chronic skin wounds represents a major therapeutic challenge. The synthesized dipeptide (Glu-Trp-ONa) and its acylated analogue (R-Glu-Trp-ONa) were assessed in the model of nonhealing dermal wounds in rabbits in relation to their healing properties in wound closure. Following wound modeling, the rabbits received a course of intraperitoneal injections of Glu-Trp-ONa or R-Glu-Trp-ONa. Phosphate-buffered saline and Solcoseryl® were applied as negative and positive control agents, respectively. An injection of Glu-Trp-ONa and R-Glu-Trp-ONa decreased the period of wound healing in animals in comparison to the control and Solcoseryl-treated groups. Acylation of Glu-Trp-ONa proved to be beneficial as related to the healing properties of the dipeptide. Subsequent zymography analyses showed that the applied peptides decreased the proteolytic activity of matrix metalloproteinases MMP-9, MMP-8, and MMP-2 in the early inflammatory phase and reversely increased the activity of MMP-9, MMP-8, and MMP-1 in the remodeling phase. Histological analyses of the wound sections (hematoxylin-eosin, Mallory's staining) confirmed the enhanced formation of granulation tissue and re-epithelialization in the experimental groups. By administering the peptides, wound closures increased significantly through the modulation of the MMPs' activity, indicating their role in wound healing.

Adult vascular wall resident multipotent vascular stem cells, matrix metalloproteinases, and arterial aneurysms

Evidences have shown the presence of multipotent stem cells (SCs) at sites of arterial aneurysms: they can differentiate into smooth muscle cells (SMCs) and are activated after residing in a quiescent state in the vascular wall. Recent studies have implicated the role of matrix metalloproteinases in the pathogenesis of arterial aneurysms: in fact the increased synthesis of MMPs by arterial SMCs is thought to be a pivotal mechanism in aneurysm formation. The factors and signaling pathways involved in regulating wall resident SC recruitment, survival, proliferation, growth factor production, and differentiation may be also related to selective expression of different MMPs. This review explores the relationship between adult vascular wall resident multipotent vascular SCs, MMPs, and arterial aneurysms.

(−)-Epigallocatechin-3-gallate inhibits matrix metalloproteinases in oral ulcers

The overexpression of MMPs results in excessive extracellular matrix degradation and oral ulcer healing delay.